Ground-water quality in the Appalachian Plateaus, Kanawha River basin, West Virginia

USGS Publications Warehouse

Sheets, Charlynn J.; Kozar, Mark D.

2000-01-01

Water samples collected from 30 privately-owned and small public-supply wells in the Appalachian Plateaus of the Kanawha River Basin were analyzed for a wide range of constituents, including bacteria, major ions, nutrients, trace elements, radon, pesticides, and volatile organic compounds. Concentrations of most constituents from samples analyzed did not exceed U.S. Environmental Protection Agency (USEPA) standards. Constituents that exceeded drinking-water standards in at least one sample were total coliform bacteria, Escherichia coli (E. coli), iron, manganese, and sulfate. Total coliform bacteria were present in samples from five sites, and E. coli were present at only one site. USEPA secondary maximum contaminant levels (SMCLs) were exceeded for three constituents -- sulfate exceeded the SMCL of 250 mg/L (milligrams per liter) in samples from 2 of 30 wells; iron exceeded the SMCL of 300 ?g/L (micrograms per liter) in samples from 12 of the wells, and manganese exceeded the SMCL of 50 ?g/L in samples from 17 of the wells sampled. None of the samples contained concentrations of nutrients that exceeded the USEPA maximum contaminant levels (MCLs) for these constituents. The maximum concentration of nitrate detected was only 4.1 mg/L, which is below the MCL of 10 mg/L. Concentrations of nitrate in precipitation and shallow ground water are similar, potentially indicating that precipitation may be a source of nitrate in shallow ground water in the study area. Radon concentrations exceeded the recently proposed maximum contaminant level of 300 pCi/L at 50 percent of the sites sampled. The median concentration of radon was only 290 pCi/L. Radon-222 is a naturally occurring, carcinogenic, radioactive decay product of uranium. Concentrations, however, did not exceed the alternate maximum contaminant level (AMCL) for radon of 4,000 pCi/L in any of the 30 samples. Arsenic concentrations exceeded the proposed MCL of 5?g/L at 4 of the 30 sites. No samples exceeded the current MCL of 50 ?g/L. Neither pesticides nor volatile organic compounds (VOCs) were prevalent in the study area, and the concentrations of the compounds that were detected did not exceed any USEPA MCLs. Pesticides were detected in only two of the 30 wells sampled, but four pesticides -- atrazine, carbofuran, DCPA, and deethylatrazine -- were detected in one well; molinate was detected in the other well. All of the pesticides detected were at estimated concentrations of only 0.002 ?g/L. Of the VOCs detected, trihalomethane compounds (THMs), which can result from chlorination of a well, were the most common. THMs were detected in 13 of the 30 wells sampled. Gasoline by-products, such as benzene, toluene, ethylbenzene and xylene (BTEX compounds) were detected in 10 of the 30 wells sampled. The maximum concentration of any of the VOCs detected in this study, however, was only 1.040 ?g/L, for the THM dichlorofluoromethane. Water samples from 25 of the wells were analyzed for chlorofluorocarbons (CFCs) to estimate the apparent age of ground water. The analyses indicated that age of water ranged from 10 to greater than 57 years, and that the age of ground water could be correlated with the topographic setting of the wells sampled. Thus the apparent age of water in wells on hilltops was youngest (median of 13 years) and that of water in wells in valleys was oldest (median of 42 years). Water from wells on hillsides was intermediate in age (median of 29 years). These data can be used to define contributing areas to wells, corroborate or revise conceptual ground-water flow models, estimate contaminant travel times from spills to other sources such as nearby domestic or public supply wells, and to manage point and nonpoint source activities that may affect critical aquifers.

Shallow Ground-Water Quality in Agricultural Areas of Northern Alabama and Middle Tennessee, 2000-2001

USGS Publications Warehouse

Kingsbury, James A.

2003-01-01

As part of the U.S. Geological Survey National Water-Quality Assessment Program, 32 monitoring wells were installed near cropland in parts of northern Alabama and Middle Tennessee to characterize the effect of row-crop agriculture on shallow ground-water quality. The wells were completed in regolith overlying carbonate bedrock. These geologic units are part of the Mississippian carbonate aquifer, a source of drinking water for domestic and municipal supply in the area. The majority of these wells were sampled in the spring of 2000 for inorganic constituents, nutrients, pesticides, and selected pesticide degradates. Land use and soil characteristics were delineated for a 1,640-foot radius buffer area around each well to relate water quality to environmental factors. A strong association among soil characteristics, land use, and hydrogeology limited the analysis of the effect of these factors on nitrate and pesticide occurrence. Nitrate and pesticide concentrations generally were low, and no samples exceeded established drinking-water maximum contaminant levels. The maximum concentration of nitrate was about 8 milligrams per liter as nitrogen, and the median concentration was 1 milligram per liter. Nitrate concentrations were strongly correlated to dissolved-oxygen concentrations, and ratios of chloride to nitrate indicate nitrate concentrations were affected by denitrification in about a third of the samples. A pesticide or pesticide degradate was detected at concentrations greater than 0.01 microgram per liter in 91 percent of the samples. Pesticides with the highest use typically were detected most frequently and at the highest concentrations; however, glyphosate had the highest estimated use but was not detected in any samples. Fluometuron and atrazine, two high-use pesticides, were detected in 83 and 70 percent, respectively, of the samples from wells where the pesticide was applied in the buffer area. Maximum concentrations of fluometuron and atrazine were 2.13 and 1.83 micrograms per liter, respectively. Detection rates of pesticide degradates were similar to parent pesticides, and concentrations of degradates generally were comparable to or greater than the parent pesticide. Pesticide detections were correlated to dissolved-oxygen concentrations, suggesting that pesticides are most likely to be detected at high concentrations where ground-water residence time is short and the rate of recharge is fast. Nitrate and pesticide data collected in this study were compared to data collected from similar agricultural land-use studies conducted by the National Water-Quality Assessment Program throughout the Nation. Nitrate concentrations generally were lower in this study than in samples from other agricultural areas; however, pesticides were detected more frequently in samples from wells in this study. For example, atrazine and its degradate, deethylatrazine, were detected in 62 and 47 percent, respectively, of water samples in this study but were detected in about 25 percent of the 851 wells sampled for agricultural land-use studies nationwide. In national study areas where atrazine use is greater than in the lower Tennessee River Basin, atrazine was detected in 30 percent of the water samples. Pesticides used on cotton were detected much more frequently in this study, but many of the study areas nationwide have smaller amounts of cotton acreage than the lower Tennessee River Basin. Similarities in nitrate concentrations and the pesticides detected frequently in this agricultural land-use study and a network of drinking-water wells in the same area completed in bedrock in the Mississippian carbonate aquifer (sampled in a previous study) indicate the aquifer is susceptible to contamination from nonpoint sources. Nitrate concentrations were not statistically different for the two well networks and were correlated to total pesticide concentrations in both networks. Although detection frequencies and maximum concentrations

Quality of water and chemistry of bottom sediment in the Rillito Creek basin, Tucson, Arizona, 1986-92

USGS Publications Warehouse

Tadayon, Saeid; Smith, C.F.

1994-01-01

Data were collected on physical properties and chemistry of 4 surface water, l4 ground water, and 4 bottom sediment sites in the Rillito Creek basin where artificial recharge of surface runoff is being considered. Concentrations of suspended sediment in streams generally increased with increases in streamflow and were higher during the summer. The surface water is a calcium and bicarbonate type, and the ground water is calcium sodium and bicarbonate type. Total trace ek=nents in surface water that exceeded the U.S. Environmental Protection Agency primary maximum contaminant levels for drinking-water standards were barium, beryllium, cadmium, chromium, lead, mercury and nickel. Most unfiltered samples for suspended gross alpha as uranium, and unadjusted gross alpha plus gross beta in surface water exceeded the U.S. Environmental Protection Agency and the State of Arizona drinking-water standards. Comparisons of trace- element concentrations in bottom sediment with those in soils of the western conterminous United States generally indicate similar concentrations for most of the trace elements, with the exceptions of scandium and tin. The maximum concentration of total nitrite plus nitrate as nitrogen in three ground- samples and total lead in one ground-water sample exceeded U.S. Environmental Protection Agency primary maximum contaminant levels for drinking- water standards, respectively. Seven organochlorine pesticides were detected in surface-water samples and nine in bottom-sediment samples. Three priority pollutants were detected in surface water, two were detected in ground water, and eleven were detected in bottom sediment. Low concentrations of oil and grease were detected in surface-water and bottom- sediment samples.

Ground-Water Quality in the St. Lawrence River Basin, New York, 2005-06

USGS Publications Warehouse

Nystrom, Elizabeth A.

2007-01-01

The Federal Clean Water Act requires that States monitor and report on the quality of ground water and surface water. To satisfy part of these requirements, the U.S. Geological Survey and New York State Department of Environmental Conservation have developed a program in which ground-water quality is assessed in 2 to 3 of New York State's 14 major river basins each year. To characterize the quality of ground water in the St. Lawrence River Basin in northern New York, water samples were collected from 14 domestic and 11 production wells between August 2005 and January 2006. Eight of the wells were finished in sand and gravel and 17 wells were finished in bedrock. Ground-water samples were collected and processed using standard U.S. Geological Survey procedures and were analyzed for 229 constituents and physical properties, including inorganic constituents, nutrients, trace elements, radon-222, pesticides and pesticide degradates, volatile organic compounds, and bacteria. Sixty-six constituents were detected above laboratory reporting levels. Concentrations of most compounds at most sites were within drinking water standards established by the U.S. Environmental Protection Agency and New York State Department of Health, but a few compounds exceeded drinking water standards at some sites. Water in the basin is generally hard to very hard (hardness equal to 121 mg/L as CaCO3 or greater); hardness and alkalinity were generally higher in the St. Lawrence Valley than in the Adirondack Mountains. The cation with the highest median concentration was calcium; the anion with the highest median concentration was bicarbonate. The concentration of chloride in one sample exceeded the 250 milligrams per liter U.S. Environmental Protection Agency Secondary Drinking Water Standard; the concentration of sulfate in one sample also exceeded the 250 milligrams per liter U.S. Environmental Protection Agency Secondary Drinking Water Standard. Nitrate was the predominant nutrient detected but no sample exceeded the 10 mg/L U.S. Environmental Protection Agency Maximum Contaminant Level. The trace elements detected with the highest median concentrations were strontium, barium, and iron. Concentration of trace elements in several samples exceeded U.S. Environmental Protection Agency Secondary Drinking Water Standards, including aluminum (50 micrograms per liter, 4 samples), iron (300 micrograms per liter, 5 samples), and manganese (50 micrograms per liter, 4 samples). The concentration of uranium in one sample from a domestic well finished in crystalline bedrock was three times the U.S. Environmental Protection Agency Maximum Contaminant Level of 30 micrograms per liter. The median concentration of radon-222 was 600 picoCuries per liter, but concentrations as high as 18,800 picoCuries per liter were detected; two wells with high radon concentrations also had high uranium concentrations. Radon-222 is not currently regulated, but the U.S. Environmental Protection Agency has proposed a Maximum Contaminant Level of 300 picoCuries per liter along with an Alternative Maximum Contaminant Level of 4,000 picoCuries per liter, to be in effect in states that have programs to address radon in indoor air. Concentrations of radon-222 exceeded the proposed Maximum Contaminant Level in 60 percent of samples and exceeded the proposed Alternative Maximum Contaminant Level in 8 percent of samples. Six pesticides and pesticide degradates were detected; all were amide or triazine herbicides or degradates. Five volatile organic compounds were detected, including disinfection byproducts such as trichloromethane and gasoline components or additives such as methyl tert-butyl ether. No pesticides, pesticide degradates, or volatile organic compounds were detected above established limits. Coliform bacteria, including Escherichia coli, were detected in three wells finished in carbonate bedrock.

Concentrations of organic contaminants detected during managed flow conditions, San Joaquin River and Old River, California, 2001

USGS Publications Warehouse

Orlando, James L.; Kuivila, Kathryn

2005-01-01

Concentrations of organic contaminants were determined in water samples collected at six surface-water sites located along the San Joaquin and Old Rivers during April through June 2001. Water samples were collected, coincident with salmon smolt caging studies conducted by researchers from the Bodega Marine Laboratory at the University of California at Davis to characterize exposure of the salmon smolt to organic contaminants. Sampling occurred prior to, during, and following the implementation of managed streamflow conditions on the San Joaquin and Old Rivers as part of the Vernalis Adaptive Management Plan. Thirteen pesticides were detected in water samples collected during this study, and at least five pesticides were detected in each sample. The total number of pesticide detections varied little between river systems and between sites, but the maximum concentrations of most pesticides occurred in San Joaquin River samples. The total number of pesticides detected varied little over the three time periods. However, during the period of managed streamflow, the fewest number of pesticides were detected at their absolute maximum concentration. Nine wastewater compounds were detected during this study. Suspended-sediment concentrations were similar for the San Joaquin and Old Rivers except during the period of managed streamflow conditions, when suspended-sediment concentration was higher at sites on the San Joaquin River than at sites on the Old River. Values for water parameters (pH, specific conductance, and hardness) were lowest during the period of managed flows.

A summary of pesticides in ground-water data collected by government agencies in Indiana, December 1985 to April 1991

USGS Publications Warehouse

Risch, M.R.

1994-01-01

More than 1 pesticide was present in 16 of the 51 samples that had detections, for a total of 90 individual pesticide detections. Concentrations of the detected pesticides ranged from 0.04 to 49 micrograms per liter, and two-thirds of the detected concentrations were less than 1 microgram per liter. In about 29 percent of all detections, the concentration of 9 pesticides alachlor, aldrin, atrazine, dieldrin, EDB, heptachlor, heptachlor epoxide, simazine, and terbufos exceeded either the U.S. Environmental Protection Agency's Maximum Contaminant Level or adult lifetime Health Advisory.

Metals, pesticides, and semivolatile organic compounds in sediment in Valley Forge National Historical Park, Montgomery County, Pennsylvania

USGS Publications Warehouse

Reif, Andrew G.; Sloto, Ronald A.

1997-01-01

The Schuylkill River flows through Valley Forge National Historical Park in Lower Providence and West Norriton Townships in Montgomery County, Pa. The concentration of selected metals, pesticides, semivolatile organic compounds, and total carbon in stream-bottom sediments from Valley Forge National Historical Park were determined for samples collected once at 12 sites in and around the Schuylkill River.Relatively low concentrations of arsenic, chromium, copper, and lead were detected in all samples. The concentrations of these metals are similar to concentrations in other stream-bottom sediment samples collected in the region. The concentrations of iron, manganese, and zinc were elevated in samples from four sites in the Schuylkill River, and the concentration of mercury was elevated in a sample from an impoundment along the river.The organophosphorus insecticide diazinon was detected in relatively low concentrations in half of the 12 samples analyzed. The organo-chlorine insecticide DDE was detected in all 12 samples analyzed; dieldrin was detected in 10 samples, chlordane, DDD, and DDT were detected in 9 samples, and heptachlor epoxide was detected in one sample. The concentrations of organo-chlorine and organophosphorus insecticides were relatively low and similar to concentrations in samples collected in the region.Detectable concentrations of 17 semivolatile organic compounds were measured in the 12 samples analyzed. The most commonly detected compounds were fluoranthene, phenanthrene, and pyrene. The maximum concentration detected was 4,800 micrograms per kilogram of phenanthrene. The highest concentrations of compounds were detected in Lamb Run, a small tributary to the Schuylkill River with headwaters in an industrial corporate center. The concentration of compounds in the Schuylkill River below Lamb Run is higher than the Schuylkill River above Lamb Run, indicating that sediment from Lamb Run is increasing the concentration of semivolatile organic compounds in sediment from the Schuylkill River. Concentrations of semivolatile organic compounds are lower in sediment from the Schuylkill River below Myer's Run than above Myer's Run because of the addition of relatively clean sediment from Myer's Run. Samples collected from the floodplain, impounding basin, and wetland along the Schuylkill River contained the lowest concen-trations of semivolatile organic compounds.Detectable concentrations of polychlorinated biphenyls (PCB's) were measured in 11 of the 12 samples analyzed. The maximum PCB concentration was 37 micrograms per kilogram. Sediment samples from Lamb Run contained the highest concentrations of semivolatile organic compounds and PCB's.

Pesticides in Water and Suspended Sediment of the Alamo and New Rivers, Imperial Valley/Salton Sea Basin, California, 2006-2007

USGS Publications Warehouse

Orlando, James L.; Smalling, Kelly L.; Kuivila, Kathryn

2008-01-01

Water and suspended-sediment samples were collected at eight sites on the Alamo and New Rivers in the Imperial Valley/Salton Sea Basin of California and analyzed for both current-use and organochlorine pesticides by the U.S. Geological Survey. Samples were collected in the fall of 2006 and spring of 2007, corresponding to the seasons of greatest pesticide use in the basin. Large-volume water samples (up to 650 liters) were collected at each site and processed using a flow-through centrifuge to isolate suspended sediments. One-liter water samples were collected from the effluent of the centrifuge for the analysis of dissolved pesticides. Additional samples were collected for analysis of dissolved organic carbon and for suspended-sediment concentrations. Water samples were analyzed for a suite of 61 current-use and organochlorine pesticides using gas chromatography/mass spectrometry. A total of 25 pesticides were detected in the water samples, with seven pesticides detected in more than half of the samples. Dissolved concentrations of pesticides observed in this study ranged from below their respective method detection limits to 8,940 nanograms per liter (EPTC). The most frequently detected compounds in the water samples were chlorpyrifos, DCPA, EPTC, and trifluralin, which were observed in more than 75 percent of the samples. The maximum concentrations of most pesticides were detected in samples from the Alamo River. Maximum dissolved concentrations of carbofuran, chlorpyrifos, diazinon, and malathion exceeded aquatic life benchmarks established by the U.S. Environmental Protection Agency for these pesticides. Suspended sediments were analyzed for 87 current-use and organochlorine pesticides using microwave-assisted extraction, gel permeation chromatography for sulfur removal, and either carbon/alumina stacked solid-phase extraction cartridges or deactivated Florisil for removal of matrix interferences. Twenty current-use pesticides were detected in the suspended-sediment samples, including pyrethroid insecticides and fungicides. Fourteen legacy organochlorine pesticides also were detected in the suspended-sediment samples. Greater numbers of current-use and organochlorine pesticides were observed in the Alamo River samples in comparison with the New River samples. Maximum concentrations of current-use pesticides in suspended-sediment samples ranged from below their method detection limits to 174 micrograms per kilogram (pendimethalin). Most organochlorine pesticides were detected at or below their method detection limits, with the exception of p,p'-DDE, which had a maximum concentration of 54.2 micrograms per kilogram. The most frequently detected current-use pesticides in the suspended-sediment samples were chlorpyrifos, permethrin, tetraconazole, and trifluralin, which were observed in more than 83 percent of the samples. The organochlorine degradates p,p'-DDD and p,p'-DDE were detected in all suspended-sediment samples.

Concentrations of selected pharmaceuticals and antibiotics in south-central Pennsylvania waters, March through September 2006

USGS Publications Warehouse

Loper, Connie A.; Crawford, J. Kent; Otto, Kim L.; Manning, Rhonda L.; Meyer, Michael T.; Furlong, Edward T.

2007-01-01

This report presents environmental and quality-control data from analyses of 15 pharmaceutical and 31 antibiotic compounds in water samples from streams and wells in south-central Pennsylvania. The analyses are part of a study by the U.S. Geological Survey (USGS) in cooperation with the Pennsylvania Department of Environmental Protection (PADEP) to define concentrations of selected emerging contaminants in streams and well water in Pennsylvania. Sampling was conducted at 11 stream sites and at 6 wells in 9 counties of south-central Pennsylvania. Five of the streams received municipal wastewater and 6 of the streams received runoff from agricultural areas dominated by animal-feeding operations. For all 11 streams, samples were collected at locations upstream and downstream of the municipal effluents or animal-feeding operations. All six wells were in agricultural settings. A total of 120 environmental samples and 21 quality-control samples were analyzed for the study. Samples were collected at each site in March/April, May, July, and September 2006 to obtain information on changes in concentration that could be related to seasonal use of compounds.For streams, 13 pharmaceuticals and 11 antibiotics were detected at least 1 time. Detections included analytical results that were estimated or above the minimum reporting limits. Seventy-eight percent of all detections were analyzed in samples collected downstream from municipal-wastewater effluents. For streams receiving wastewater effluents, the pharmaceuticals caffeine and para-xanthine (a degradation product of caffeine) had the greatest concentrations, 4.75 μg/L (micrograms per liter) and 0.853 μg/L, respectively. Other pharmaceuticals and their respective maximum concentrations were carbamazepine (0.516 μg/L) and ibuprofen (0.277 μg/L). For streams receiving wastewater effluents, the antibiotic azithromycin had the greatest concentration (1.65 μg/L), followed by sulfamethoxazole (1.34 μg/L), ofloxacin (0.329 μg/L), and trimethoprim (0.256 μg/L).For streams receiving runoff from animal-feeding operations, the only pharmaceuticals detected were acetaminophen, caffeine, cotinine, diphenhydramine, and carbamazepine. The maximum concentration for pharmaceuticals was 0.053 μg/L. Three streams receiving runoff from animal-feeding operations had detections of one or more antibiotic compound--oxytetracycline, sulfadimethoxine, sulfamethoxazole, and tylosin. The maximum concentration for antibiotics was 0.157 μg/L. The average number of compounds (pharmaceuticals and antibiotics) detected in sites downstream from animal-feeding operations was three. The average number of compounds detected downstream from municipal-wastewater effluents was 13.For wells used to supply livestock, four compounds were detected--two pharmaceuticals (cotinine and diphenhydramine) and two antibiotics (tylosin and sulfamethoxazole). There were five detections in all the well samples. The maximum concentration detected in well water was for cotinine, estimated to be 0.024 μg/L.Seasonal occurrence of pharmaceutical and antibiotic compounds in stream water varied by compound and site type. At four stream sites, the same compounds were detected in all four seasonal samples. At other sites, pharmaceutical or antibiotic compounds were detected only one time in seasonal samples. Winter samples collected in streams receiving municipalwastewater effluent had the greatest number of compounds detected (21). Research analytical methods were used to determine concentrations for pharmaceuticals and antibiotics. To assist in evaluating the quality of the analyses, detailed information is presented on laboratory methodology and results from qualitycontrol samples. Quality-control data include results for nine blanks, nine duplicate environmental sample pairs, and three laboratory-spiked environmental samples as well as the recoveries of compounds in laboratory surrogates and laboratory reagent spikes.

Geology, hydrology, and water quality of the glacial drift aquifer in the vicinity of the Nelson landfill near Yorkville, Illinois

USGS Publications Warehouse

Kay, Robert T.

2006-01-01

The geologic and hydrologic characteristics of the sand-and-gravel deposits that compose the glacial drift aquifer in the vicinity of the Nelson Landfill site in Yor-kville, Illinois indicate that the aquifer could be devel-oped as a source of public water supply. The geology of these deposits within the Newark Bedrock Valley is com-plex, however, and a detailed investigation of their water bearing and transmitting properties will be required to successfully locate high-capacity wells. Volatile organic compounds, pesticides, and cyanide were not detected in ground water during this investiga-tion. Metals and nitrogen compounds were not detected at concentrations above their Maximum Contaminant Level. Iron, manganese, and aluminum were detected at concentrations above their Secondary Maximum Con-taminant Level and various constituents were detected at concentrations above background levels downgradi-ent of the landfill. Nitrate and ammonia, presumably derived from agricultural practices, also were detected in samples from locations hydraulically upgradient of the landfill. Oxidation-reduction conditions in the aquifer become more reducing with depth. This change is reflected by a change in the type of nitrogen compound detected and the concentration of dissolved oxygen and iron in the glacial drift aquifer. Concentrations of some of the major ions and metals may be affected by disso-lution of carbonate minerals in the aquifer and perhaps road salts.

Time-course measurements of drug concentrations in hair and toenails after single administrations of pharmaceutical products.

PubMed

Kuwayama, Kenji; Miyaguchi, Hajime; Iwata, Yuko T; Kanamori, Tatsuyuki; Tsujikawa, Kenji; Yamamuro, Tadashi; Segawa, Hiroki; Inoue, Hiroyuki

2017-04-01

Hair and nails are often used to prove long-term intake of drugs in forensic drug testing. The aim of this study was to evaluate the effectiveness of drug testing using hair and nails and the feasibility of determining when drugs were ingested by measuring the time-courses of drug concentrations in hair and toenails after single administrations of various drugs. Healthy subjects ingested four pharmaceutical products containing eight active ingredients in single doses. Hair and toenails were collected at predetermined intervals, and drug concentrations in hair and nails were measured for 12 months. The administered drugs and their main metabolites were extracted using micropulverized extraction with a stainless steel bullet and were analyzed using liquid chromatography/tandem mass spectrometry. Acidic compounds such as ibuprofen and its metabolites were not detected in both specimens. Acetaminophen, a weakly acidic compound, was detected in nails more frequently than in hair. The maximum concentration of allyl isopropyl acetylurea, a neutral compound, in nails was significantly higher than in hair. Nails are an effective specimen to detect neutral and weakly acidic compounds. For fexofenadine, a zwitterionic compound, and for most basic compounds, the maximum concentrations in hair segments tended to be higher than those in nails. The hair segments showing the maximum concentrations varied between drugs, samples, and subjects. Drug concentrations in hair segments greatly depended on the selection of the hair. Careful interpretation of analytical results is required to predict the time of drug intake. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Pesticide concentrations in wetlands on the Lake Traverse Indian Reservation, South and North Dakota, July 2015

USGS Publications Warehouse

Carter, Janet M.; Thompson, Ryan F.

2016-05-04

During July 2015, water samples were collected from 18 wetlands on the Lake Traverse Indian Reservation in northeastern South Dakota and southeastern North Dakota and analyzed for physical properties and 54 pesticides. This study by the U.S. Geological Survey in cooperation with the Sisseton-Wahpeton Oyate was designed to provide an update on pesticide concentrations of the same 18 wetlands that were sampled for a reconnaissance-level assessment during July 2006. The purpose of this report is to present the results of the assessment of pesticide concentrations in selected Lake Traverse Indian Reservation wetlands during July 2015 and provide a comparison of pesticide concentrations between 2006 and 2015.Of the 54 pesticides that were analyzed for in the samples collected during July 2015, 47 pesticides were not detected in any samples. Seven pesticides—2-chloro-4-isopropylamino-6-amino-s-triazine (CIAT); 2,4–D; acetachlor; atrazine; glyphosate; metolachlor; and prometon—were detected in the 2015 samples with estimated concentrations or concentrations greater than the laboratory reporting level, and most pesticides were detected at low concentrations in only a few samples. Samples from all wetlands contained at least one detected pesticide. The maximum number of pesticides detected in a wetland sample was six, and the median number of pesticides detected was three.The most commonly detected pesticides in the 2015 samples were atrazine and the atrazine degradate CIAT (also known as deethylatrazine), which were detected in 14 and 13 of the wetlands sampled, respectively. Glyphosate was detected in samples from 11 wetlands, and metolachlor was detected in samples from 10 wetlands. The other detected pesticides were 2,4–D (4 wetlands), acetochlor (3 wetlands), and prometon (1 wetland).The same pesticides that were detected in the 2006 samples were detected in the 2015 samples, with the exception of simazine, which was detected only in one sample in 2006. Atrazine and CIAT were the most commonly detected pesticides in both sampling years; however, atrazine and CIAT were detected in fewer wetlands in 2015 (14 and 13 wetlands, respectively) than in 2006 (17 wetlands for both pesticides). The pesticides 2,4–D and prometon also were detected in fewer wetlands in 2015 than 2006, and simazine was only detected in 2006. In contrast, acetochlor, glyphosate, and metolachlor were detected in samples from more wetlands in 2015 than in 2006. In samples from individual wetlands, the number of pesticides detected was similar between 2006 and 2015. At least one pesticide was detected in all wetlands in 2015, and all but one wetland had pesticide detections in 2006.Concentrations of pesticides detected in samples from wetlands were compared to selected water-quality (human-health and aquatic-life) benchmarks. None of the concentrations in either 2006 or 2015 were greater than water-quality benchmarks, with the exception of atrazine. All detections of atrazine in the 2006 and 2015 samples were greater than the acute benchmark of 0.001 microgram per liter (μg/L) for vascular plants. In addition, some concentrations of 2,4–D and atrazine were within an order of magnitude of a water-quality benchmark. The 2,4–D concentrations in the 2015 samples from three wetlands were within an order of magnitude of the U.S. Environmental Protection Agency’s Maximum Contaminant Level of 70 μg/L (that is, sample concentrations were greater than 7.0 μg/L). The maximum dissolved atrazine concentration of 0.185 μg/L in the 2015 samples along with the concentrations in 2006 samples from two wetlands were within an order of magnitude of the acute benchmark of less than 1 μg/L for nonvascular plants (that is, concentrations were greater than 0.1 μg/L).

Water quality of the Mississippian carbonate aquifer in parts of middle Tennessee and northern Alabama, 1999

USGS Publications Warehouse

Kingsbury, James A.; Shelton, John M.

2002-01-01

Water-quality data for nitrate, fecal-indicator bacteria, pesticides, and volatile organic compounds collected in parts of Middle Tennessee and northern Alabama indicate that the Mississippian carbonate aquifer in these areas is susceptible to contamination from point and nonpoint sources. Thirty randomly located wells (predominantly domestic), two springs, and two additional public-supply wells were sampled in the summer of 1999 as part of the U.S. Geological Survey?s National Water-Quality Assessment (NAWQA) Program. These wells and springs were sampled to characterize the occurrence and distribution of the above constituents in this karst aquifer of Mississippian age and to determine the principal environmental factors related to their occurrence.Nitrate and fecal indicator bacteria were frequently detected at the sampled sites. Nitrate exceeded the drinking-water maximum contaminant level of 10 milligrams per liter in two samples; the median concentration for all samples was about 1.5 milligrams per liter. Correlation of nitrate concentrations to the amount of cropland near a site and to pesticide detections indicates that fertilizer application is the predominant source of nitrogen to the aquifer. Fecal-indicator bacteria were present in samples from about 40 percent of the sites. The presence of fecal-indicator bacteria is weakly correlated to the depth to ground water but is not correlated to a specific land use near the sites.Pesticides and pesticide breakdown products (metabolites) were detected at 74 percent of the sites sampled. Concentrations generally were less than 1 microgram per liter and no pesticide detections exceeded drinking-water maximum contaminant levels. The maximum total pesticide concentration measured was about 4 micrograms per liter. Intensity of pesticide use, proximity of sites to areas of pesticide application, and soil hydrologic group were the primary factors affecting the occurrence of pesticides.Volatile organic compounds were detected at generally low concentrations at about 81 percent of the sites sampled. Concentrations of trichloroethylene, tetrachloroethylene, and 1,2-dichloropropane at three sites equalled or exceeded drinking-water maximum contaminant levels. The maximum concentration measured was 7.5 micrograms per liter of trichloroethylene. The presence of volatile organic compounds in the Mississippian carbonate aquifer was not related to hydrogeology, soil properties, or land use near the sites; although higher total volatile organic compound concentrations and greater numbers of compounds in samples generally were associated with a higher percentage of urban land use near a site. Chloroform was the most frequently detected compound, and correlation of low-level detections to the amount of wetlands near sites having these detections may indicate biogenic formation of chloroform.The relation between land use and water quality was stronger for constituents that are contributed to the environment systematically (fertilizer and pesticide applications), than those contributed inadvertently (leaking septic tanks or chemical spills or leaks). Land use and soils characterized in circular buffer areas near sites sampled in this karst aquifer explained some of the variation in nitrate concentration and presence of pesticides. Use of land use and soil data with greater detail than the large scale data used in this analysis and buffer areas based on well capacities and ground-water withdrawals might strengthen this type of analysis.

A Survey of Naturally-Occurring Steroid Hormones in Raw Milk and the Associated Health Risks in Tangshan City, Hebei Province, China

PubMed Central

Qu, Xueyin; Su, Chuanyou; Zheng, Nan; Li, Songli; Meng, Lu; Wang, Jiaqi

2017-01-01

In recent years, high levels of hormone residue in food, capable of damaging the health of consumers, have been recorded frequently. In this study, 195 raw milk samples were obtained from Tangshan City, China, and the concentrations of 22 steroid hormones were measured by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Cortisol was detected in 12.5% of raw milk samples (mean 0.61 µg/kg; range:

Similarities and differences in occurrence and temporal fluctuations in glyphosate and atrazine in small Midwestern streams (USA) during the 2013 growing season

USGS Publications Warehouse

Mahler, Barbara J.; Van Metre, Peter C.; Burley, Thomas E.; Loftin, Keith A.; Meyer, Michael T.; Nowell, Lisa H.

2017-01-01

Glyphosate and atrazine are the most intensively used herbicides in the United States. Although there is abundant spatial and temporal information on atrazine occurrence at regional scales, there are far fewer data for glyphosate, and studies that compare the two herbicides are rare. We investigated temporal patterns in glyphosate and atrazine concentrations measured weekly during the 2013 growing season in 100 small streams in the Midwestern United States. Glyphosate was detected in 44% of samples (method reporting level 0.2 μg/L); atrazine was detected above a threshold of 0.2 μg/L in 54% of samples. Glyphosate was detected more frequently in 12 urban streams than in 88 agricultural streams, and at concentrations similar to those in streams with high agricultural land use (> 40% row crop) in the watershed. In contrast, atrazine was detected more frequently and at higher concentrations in agricultural streams than in urban streams. The maximum concentration of glyphosate measured at most urban sites exceeded the maximum atrazine concentration, whereas at agricultural sites the reverse was true. Measurement at a 2-day interval at 8 sites in northern Missouri revealed that transport of both herbicide compounds appeared to be controlled by spring flush, that peak concentration duration was brief, but that peaks in atrazine concentrations were of longer duration than those of glyphosate. The 2-day sampling also indicated that weekly sampling is unlikely to capture peak concentrations of glyphosate and atrazine.

Ground-water quality, Cook Inlet Basin, Alaska, 1999

USGS Publications Warehouse

Glass, Roy L.

2001-01-01

As part of the U.S. Geological Survey?s National Water-Quality Assessment Program, ground-water samples were collected from 34 existing wells in the Cook Inlet Basin in south-central Alaska during 1999. All ground-water samples were from aquifers composed of glacial or alluvial sediments. The water samples were used to determine the occurrence and distribution of selected major ions, nutrients, trace elements, volatile organic compounds, pesticides, radioisotopes, and environmental isotopes. Of 34 samples, 29 were from wells chosen by using a grid-based random-selection process. Water samples from five major public-supply wells also were collected. Radon-222 and arsenic concentrations exceeded drinking-water standards proposed by the U.S. Environmental Protection Agency in 39 and 18 percent of sampled wells, respectively. The highest radon concentration measured during this study was 610 picocuries per liter; 12 of 31 samples exceeded the proposed maximum contaminant level of 300 picocuries per liter. The highest arsenic concentration was 29 micrograms per liter; 6 of 34 samples exceeded the proposed maximum contaminant level of 10 micrograms per liter. Human activities may be increasing the concen- tration of nitrate in ground water, but nitrate concentrations in all samples were less than the maximum contaminant level of 10 milligrams per liter as nitrogen. Concentrations of nitrate were highest in Anchorage and were as great as 4.8 milligrams per liter as nitrogen. Dissolved-solids concentrations ranged from 77 to 986 milligrams per liter; only 2 of 34 wells yielded water having greater than 500 milligrams per liter. Iron and manganese concentrations exceeded secondary maximum contaminant levels in 18 and 42 percent of samples, respectively. Concentrations of all pesticides and volatile organic compounds detected in ground-water samples were very low, less than 1 microgram per liter. No pesticide or volatile organic compounds were detected at concentrations exceeding drinking-water standards or guidelines. Water samples from one-half of the wells sampled had no detectable concentrations of pesticides or volatile organic carbons, at the parts-per-billion level. Concentrations of stable isotopes of hydrogen and oxygen in ground-water samples were similar to concentrations expected for modern precipitation and for water that has been affected by evaporation. Tritium activities and concentrations of chlorofluorocarbons indicated that the water samples collected from most wells were recharged less than 50 years ago.

Watershed trend analysis and water-quality assessment using bottom-sediment cores from Cheney Reservoir, south-central Kansas

USGS Publications Warehouse

Pope, Larry M.

1998-01-01

An examination of Cheney Reservoir bottom sediment was conducted in August 1997 to describe long-term trends and document the occurrence of selected constituents at concentrations that may be detrimental to aquatic organisms. Average concentrations of total phosphorus in bottom-sediment cores ranged from 94 to 674 milligrams per kilogram and were statistically related to silt- and (or) clay-size particles. Results from selected sampling sites in Cheney Reservoir indicate an increasing trend in total phosphorus concentrations. This trend is probably of nonpoint-source origin and may be related to an increase in fertilizer sales in the area, which more than doubled between 1965 and 1996, and to livestock production. Few organochlorine compounds were detected in bottom-sediment samples from Cheney Reservoir. DDT, its degradation products DDD and DDE, and dieldrin had detectable concentrations in the seven samples that were analyzed. DDT and DDD were each detected in one sample at concentrations of 1.0 and 0.65 microgram per kilogram, respectively. By far, the most frequently detected organochlorine insecticide was DDE, which was detected in all seven samples, ranging in concentration from 0.31 to 1.3 micrograms per kilogram. A decreasing trend in DDE concentrations was evident in sediment-core data from one sampling site. Dieldrin was detected in one sample from each of two sampling sites at concentrations of 0.21 and 0.22 micrograms per kilogram. Polychlorinated biphenyls were not detected in any bottom-sediment sample analyzed. Selected organophosphate, chlorophenoxy-acid, triazine, and acetanilide pesticides were analyzed in 18 bottom-sediment samples. Of the 23 pesticides analyzed, only the acetanilide herbicide metolachlor was detected (in 22 percent of the samples). Seven bottom-sediment samples were analyzed for major metals and trace elements. The median and maximum concentrations of arsenic and chromium, the maximum concentration of copper, and all concentrations of nickel in the seven samples were in the range where adverse effects to aquatic organisms occasionally occur. No time trends in trace elements were discernable in the August 1997 data.

Response to comment on "Pharmaceuticals, hormones, and other organic wastewater contaminants in U.S. streams, 1999-2000: A national reconnaissance"

USGS Publications Warehouse

Kolpin, Dana W.; Furlong, Edward T.; Meyer, Michael T.; Thurman, E. Michael; Zaugg, Steven D.; Barber, Larry B.; Buxton, Herbert T.

2003-01-01

Till (1) raised concerns that several aspects of how we handled the data in our study (2) may have caused unintended bias. First, Till (1) considers the “median detectable concentrations” listed in Table 1 (2) to be misleading because “higher median concentrations than is actually the case” were suggested. We interpret this concern raised by Till (1) to be that some readers may misinterpret our median detectable concentration to be an overall median concentration. Our intention was to provide the reader with information that could not easily be determined independently. For example, by examining the frequency of detection (2), it could easily be determined that the overall median concentration was less than the reporting level for all but six compounds (those having a detection frequency of>50%). Our goal for providing a median detectable concentration was to give a better sense of the concentrations when a particular compound was detected. Thus, we felt the combination of frequency of detection (how often a compound was found), median detectable concentration (median concentration when a compound was detected), and maximum concentration (highest concentration measured) would provide the greatest benefit to the readers. In future reports, we will modify the table headings to ensure that overall median concentration and median detectable concentration are clearly differentiated.

Nationwide reconnaissance of contaminants of emerging concern in source and treated drinking waters of the United States: Pharmaceuticals.

PubMed

Furlong, Edward T; Batt, Angela L; Glassmeyer, Susan T; Noriega, Mary C; Kolpin, Dana W; Mash, Heath; Schenck, Kathleen M

2017-02-01

Mobile and persistent chemicals that are present in urban wastewater, such as pharmaceuticals, may survive on-site or municipal wastewater treatment and post-discharge environmental processes. These pharmaceuticals have the potential to reach surface and groundwaters, essential drinking-water sources. A joint, two-phase U.S. Geological Survey-U.S. Environmental Protection Agency study examined source and treated waters from 25 drinking-water treatment plants from across the United States. Treatment plants that had probable wastewater inputs to their source waters were selected to assess the prevalence of pharmaceuticals in such source waters, and to identify which pharmaceuticals persist through drinking-water treatment. All samples were analyzed for 24 pharmaceuticals in Phase I and for 118 in Phase II. In Phase I, 11 pharmaceuticals were detected in all source-water samples, with a maximum of nine pharmaceuticals detected in any one sample. The median number of pharmaceuticals for all 25 samples was five. Quantifiable pharmaceutical detections were fewer, with a maximum of five pharmaceuticals in any one sample and a median for all samples of two. In Phase II, 47 different pharmaceuticals were detected in all source-water samples, with a maximum of 41 pharmaceuticals detected in any one sample. The median number of pharmaceuticals for all 25 samples was eight. For 37 quantifiable pharmaceuticals in Phase II, median concentrations in source water were below 113ng/L. For both Phase I and Phase II campaigns, substantially fewer pharmaceuticals were detected in treated water samples than in corresponding source-water samples. Seven different pharmaceuticals were detected in all Phase I treated water samples, with a maximum of four detections in any one sample and a median of two pharmaceuticals for all samples. In Phase II a total of 26 different pharmaceuticals were detected in all treated water samples, with a maximum of 20 pharmaceuticals detected in any one sample and a median of 2 pharmaceuticals detected for all 25 samples. Source-water type influences the presence of pharmaceuticals in source and treated water. Treatment processes appear effective in reducing concentrations of most pharmaceuticals. Pharmaceuticals more consistently persisting through treatment include carbamazepine, bupropion, cotinine, metoprolol, and lithium. Pharmaceutical concentrations and compositions from this study provide an important base data set for further sublethal, long-term exposure assessments, and for understanding potential effects of these and other contaminants of emerging concern upon human and ecosystem health. Copyright © 2016. Published by Elsevier B.V.

Assessment of shallow ground-water quality in recently urbanized areas of Sacramento, California, 1998

USGS Publications Warehouse

Shelton, Jennifer L.

2005-01-01

Evidence for anthropogenic impact on shallow ground-water quality beneath recently developed urban areas of Sacramento, California, has been observed in the sampling results from 19 monitoring wells in 1998. Eight volatile organic compounds (VOCs), four pesticides, and one pesticide transformation product were detected in low concentrations, and nitrate, as nitrogen, was detected in elevated concentrations; all of these concentrations were below National and State primary and secondary maximum contaminant levels. VOC results from this study are more consistent with the results from urban areas nationwide than from agricultural areas in the Central Valley, indicating that shallow ground-water quality has been impacted by urbanization. VOCs detected may be attributed to either the chlorination of drinking water, such as trichloromethane (chloroform) detected in 16 samples, or to the use of gasoline additives, such as methyl tert-butyl ether (MTBE), detected in 2 samples. Pesticides detected may be attributed to use on household lawns and gardens and rights-of-way, such as atrazine detected in three samples, or to past agricultural practices, and potentially to ground-water/surface-water interactions, such as bentazon detected in one sample from a well adjacent to the Sacramento River and downstream from where bentazon historically was used on rice. Concentrations of nitrate may be attributed to natural sources, animal waste, old septic tanks, and fertilizers used on lawns and gardens or previously used on agricultural crops. Seven sample concentrations of nitrate, as nitrogen, exceeded 3.0 milligrams per liter, a level that may indicate impact from human activities. Ground-water recharge from rainfall or surface-water runoff also may contribute to the concentrations of VOCs and pesticides observed in ground water. Most VOCs and pesticides detected in ground-water samples also were detected in air and surface-water samples collected at sites within or adjacent to the recently developed urban areas. Five arsenic sample concentrations exceeded the U.S. Environmental Protection Agency (USEPA) primary maximum contaminant level (MCL) of 10 milligrams per liter adopted in 2001. Measurements that exceeded USEPA or California Department of Health Services recommended secondary maximum contaminant levels include manganese, iron, chloride, total dissolved solids, and specific conductance. These exceedances are probably a result of natural processes. Variations in stable isotope ratios of hydrogen (2H/1H) and oxygen (18O/16O) may indicate different sources or a mixing of recharge waters to the urban ground water. These variations also may indicate recharge directly from surface water in one well adjacent to the Sacramento River. Tritium concentrations indicate that most shallow ground water has been recharged since the mid-1950s, and tritium/helium-3 age dates suggest that recharge has occurred in the last 2 to 30 years in some areas. In areas where water table depths exceed 20 meters and wells are deeper, ground-water recharge may have occurred prior to 1950, but low concentrations of pesticides and VOCs detected in these deeper wells indicate a mixing of younger and older waters. Overall, the recently urbanized areas can be divided into two groups. One group contains wells where few VOCs and pesticides were detected, nitrate mostly was not detected, and National and State maximum contaminant levels, including the USEPA MCL for arsenic, were exceeded; these wells are adjacent to rivers and generally are characterized by younger water, shallow (1 to 4 meters) water table, chemically reducing conditions, finer grained sediments, and higher organics in the soils. In contrast, the other group contains wells where more VOCs, pesticides, and elevated nitrate concentrations were detected; these wells are farther from rivers and are generally characterized by a mixture of young and old waters, intermediate to deep (7 to 35 meters) wate

Dissolved pesticide concentrations in the Sacramento-San Joaquin Delta and Grizzly Bay, California, 2011-12

USGS Publications Warehouse

Orlando, James L.; McWayne, Megan; Sanders, Corey; Hladik, Michelle

2013-01-01

Surface-water samples were collected from sites within the Sacramento-San Joaquin Delta and Grizzly Bay, California, during the spring in 2011 and 2012, and they were analyzed by the U.S. Geological Survey for a suite of 99 current-use pesticides and pesticide degradates. Samples were collected and analyzed as part of a collaborative project studying the occurrence and characteristics of phytoplankton in the San Francisco Estuary. Samples were analyzed by two separate laboratory methods employing gas chromatography/mass spectrometry or liquid chromatography with tandem mass spectrometry. Method detection limits ranged from 0.9 to 10.5 nanograms per liter (ng/L). Eighteen pesticides were detected in samples collected during 2011, and the most frequently detected compounds were the herbicides clomazone, diuron, hexazinone and metolachlor, and the diuron degradates 3,4-dichloroaniline and N-(3,4-dichlorophenyl)-N’-methylurea (DCPMU). Concentrations for all compounds were less than 75 ng/L, except for the rice herbicide clomazone and the fungicide tetraconazole, which had maximum concentrations of 535 and 511 ng/L, respectively. In samples collected in 2012, a total of 16 pesticides were detected. The most frequently detected compounds were the fungicides azoxystrobin and boscalid and the herbicides diuron, hexazinone, metolachlor, and simazine. Maximum concentrations for all compounds detected in 2012 were less than 75 ng/L, except for the fungicide azoxystrobin and the herbicides hexazinone and simazine, which were detected at up to 188, 134, and 140 ng/L, respectively.

Herbicides and nitrates in the Iowa River alluvial aquifer prior to changing land use, Iowa County, Iowa, 1996

USGS Publications Warehouse

Savoca, Mark E.; Tobias, Jennifer L.; Sadorf, Eric M.; Birkenholtz, Trevor L.

1997-01-01

Four herbicides (alachlor, atrazine, cyanazine, and metolachlor) and one nutrient (nitrate) were selected for study on the basis of frequent usage in Iowa and high detection rates in ground water (Detroy and Kuzniar, 1988). Alachlor was not detected at concentrations greater than the method detection limit (MDL). Atrazine was detected at concentrations greater than the MDL in samples from 48 percent of the 23 wells, cyanazine from 13 percent, metolachlor from 26 percent, and nitrate from 91 percent. None of the four herbicides were detected at concentrations greater than the respective U.S. Environmental Protection Agency's (USEPA) Maximum Contaminant Level (MCL) for drinking water. Thirteen percent of the samples had nitrate concentrations above the USEPA's MCL of 10 mg/L (milligrams per liter). Relations between constituent concentration and well depth were observed for specific constituents at individual well nests.

Groundwater-quality data in the Santa Cruz, San Gabriel, and Peninsular Ranges Hard Rock Aquifers study unit, 2011-2012: results from the California GAMA program

USGS Publications Warehouse

Davis, Tracy A.; Shelton, Jennifer L.

2014-01-01

Results for constituents with nonregulatory benchmarks set for aesthetic concerns showed that iron concentrations greater than the CDPH secondary maximum contaminant level (SMCL-CA) of 300 μg/L were detected in samples from 19 grid wells. Manganese concentrations greater than the SMCL-CA of 50 μg/L were detected in 27 grid wells. Chloride was detected at a concentration greater than the SMCL-CA upper benchmark of 500 mg/L in one grid well. TDS concentrations in three grid wells were greater than the SMCL-CA upper benchmark of 1,000 mg/L.

Characterization of the hydrogeology and water quality at the Management Systems Evaluation Area near Princeton, Minnesota, 1991-92

USGS Publications Warehouse

Delin, G.N.; Landon, M.K.; Lamb, J.A.; Anderson, J.L.

1994-01-01

Atrazine was detected by gas chromatography mass spectroscopy in 2 of the 7 wells in the research area at concentrations of 0.04 and 0.17 micrograms per liter (ug/L), well below the U.S. Environmental Protection Agency's recommended maximum contaminant level of 3 ug/L. The median concentration in these Wells was less than the qualitative detection limit of 0.01 ug/L. Atrazine metabolite de-ethylatrazine was the most frequently detected herbicide or herbicide metabolite. De-ethylatrazine was detected in 5 of the 7 wells in the research area at concentrations ranging from 0.12 to 0.32 ug/L with a median concentration of 0.14 ug/L. Atrazine metabolite de-isopropylatrazine was not detected above the qualitative detection limit of 0.06 ug/L. The most likely sources of atrazine are applications to the research area during 1990 or from precipitation.

Reconnaissance-level assessment of water and bottom-sediment quality, including pesticides and mercury, in Yankton Sioux Tribe wetlands, Charles Mix County, South Dakota, June-July 2005

USGS Publications Warehouse

Schaap, Bryan D.; Bartholomay, Roy C.

2006-01-01

During June and July 2005, water and bottom-sediment samples were collected from selected Yankton Sioux Tribe wetlands within the historic Reservation area of eastern Charles Mix County as part of a reconnaissance-level assessment by the U.S. Geological Survey and Yankton Sioux Tribe. The water samples were analyzed for pesticides and mercury species. In addition, the water samples were analyzed for physical properties and chemical constituents that might help further characterize the water quality of the wetlands. The bottom-sediment samples were analyzed for mercury species. During June 2005, water samples were collected from 19 wetlands and were analyzed for 61 widely used pesticide compounds. Many pesticides were not detected in any of the water samples and many others were detected only at low concentrations in a few of the samples. Thirteen pesticides were detected in water samples from at least one of the wetlands. Atrazine and de-ethyl atrazine were detected at each of the 19 wetlands. The minimum, maximum, and median dissolved atrazine concentrations were 0.056, 0.567, and 0.151 microgram per liter (?g/L), respectively. Four pesticides (alachlor, carbaryl, chlorpyrifos, and dicamba) were detected in only one wetland each. The number of pesticides detected in any of the 19 wetlands ranged from 3 to 8, with a median of 6. In addition to the results for this study, recent previous studies have frequently found atrazine in Lake Andes and the Missouri River, but none of the atrazine concentrations have been greater than 3 ?g/L, the U.S. Environmental Protection Agency's Maximum Contaminant Level for atrazine in drinking water. During June and July 2005, water and bottom-sediment samples were collected from 10 wetlands. Water samples from each of the wetlands were analyzed for major ions, organic carbon, and mercury species, and bottom-sediment samples were analyzed for mercury species. For the whole-water samples, the total mercury concentrations ranged from 1.11 to 29.65 nanograms per liter (ng/L), with a median of 10.56 ng/L. The methylmercury concentrations ranged from 0.45 to 14.03 ng/L, with a median of 2.28 ng/L. For the bottom-sediment samples, the total mercury concentration ranged from 21.3 to 74.6 nanograms per gram (ng/g), with a median of 54.2 ng/g. The methylmercury concentrations ranged from <0.11 to 2.04 ng/g, with a median of 0.78 ng/g. The total mercury concentrations in the water samples were all much less than 2 ?g/L (2,000 ng/L), the U.S. Environmental Protection Agency's Maximum Contaminant Level for mercury in drinking water. However, water samples from four of the wetlands had concentrations larger than 0.012 ?g/L (12 ng/L), the State of South Dakota's chronic standard for surface waters, including wetlands. Maximum methylmercury concentrations for this study are larger than reported concentrations for wetlands in North Dakota and concentrations reported for the Cheyenne River Indian Reservation in South Dakota.

Occurrence of steroid estrogens, endocrine-disrupting phenols, and acid pharmaceutical residues in urban riverine water of the Pearl River Delta, South China.

PubMed

Peng, Xianzhi; Yu, Yiyi; Tang, Caiming; Tan, Jianhua; Huang, Qiuxin; Wang, Zhendi

2008-07-01

A scoping study was conducted to investigate the residues of nineteen pharmaceuticals and personal care products (PPCPs), including 4 natural and 3 synthetic steroid estrogens, 7 endocrine-disrupting phenols, and 5 acid pharmaceuticals in three urban streams and the Major Pearl River at Guangzhou, a megapolis in the Pearl River Delta, South China. Estrone was detected in >60% water samples with a maximum concentration of 65 ng L(-1). Endocrine-disrupting phenols (nonylphenol, bisphenol A, triclosan, 2-phenylphenol, methyparaben, and propylparaben) were found to be widely present at rather high concentrations in the urban riverine water of Guangzhou. Salicylic acid, clofibric acid and ibuprofen were detected in most water samples with maximum concentrations of 2098, 248 and 1417 ng L(-1) respectively, whereas naproxen was less frequently detected and also at lower concentration. Both the detection frequencies and median concentrations of the PPCPs appeared higher during the low-flow season than during the high-flow season. The seasonal difference in PPCPs occurrence was probably attributed to the dilution effect caused by the rainfall. PPCPs in the urban riverine water of Guangzhou originated mainly from random discharge and/or leakage of municipal wastewater. PPCPs contamination in the Major Pearl River may be of a potential environmental issue, especially during the low-flow season.

Summary of airborne chlorine and hydrogen chloride gas measurements for August 20 and September 5, 1977 Voyager launches at Air Force Eastern Test Range, Florida

NASA Technical Reports Server (NTRS)

Gregory, G. L.; Emerson, B. R., Jr.; Hudgins, C. H.

1978-01-01

Airborne chlorine and hydrogen chloride measurements were made in the tropospheric ground cloud following the Voyager launches of August 20 and September 5, 1977. The maximum observed hydrogen chloride concentration for both launches was about 25 to 30 parts per million (ppm) occurring typically 2 to 6 minutes after launch. By completion of the sampling mission (1-1/2 hours for August, 4-1/2 hours for September), the maximum in-cloud concentration decayed to about 1 to 2 ppm. Maximum observed chlorine concentrations were about 40 to 55 parts per billion (ppb) about 2 to 8 minutes after launch; by about 15 minutes after launch, chlorine concentrations were less than 10 ppb (detection limit). In-cloud chlorine concentrations were well below 1 percent of hydrogen chloride concentrations. The appendix of the report discusses the chlorine instrument and the laboratory evaluation of the detector.

Annual INTEC Groundwater Monitoring Report for Group 5 - Snake River Plain Aquifer (2001)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roddy, Michael Scott

2002-02-01

This report describes the monitoring activities conducted and presents the results of groundwater sampling and water-level measurements from October 2000 to September 2001. Groundwater samples were initially collected from 41 wells from the Idaho Nuclear Technology and Engineering Center and the Central Facilities Area and analyzed for iodine-129, strontium-90, tritium, gross alpha, gross beta, technetium-99, uranium isotopes, plutonium isotopes, neptunium-237, americium-241, gamma spectrometry, and mercury. Samples from 41 wells were collected in April and May 2001. Additional sampling was conducted in August 2001 and included the two CFA production wells, the CFA point of compliance for the production wells, onemore » well that was previously sampled and five additional monitoring wells. Iodine-129 and strontium-90 were the only analytes above their respective maximum contaminant levels. Iodine-129 was detected just above its maximum contaminant level of 1 pCi/L at two of the Central Facilities Area landfill wells. Iodine-129 was detected in the CFA production wells at 0.35±0.083 pCi/L in CFA-1, but was below detectable activity in CFA-2. Strontium-90 was above its maximum contaminant level of 8 pCi/L in several wells near the Idaho Nuclear Technology and Engineering Center but was below its maximum contaminant level in the downgradient wells at the Central Facilities Area landfills. Sr-90 was not detected in the CFA production wells. Gross beta results generally mirrored the results for strontium-90 and technetium-99. Plutonium isotopes and neptunium-237 were not detected. Uranium-233/234 and uranium-238 isotopes were detected in all samples. Concentrations of background and site wells were similar and are within background limits for total uranium determined by the USGS, suggesting that the concentrations are background. Uranium-235/236 was detected in 11 samples, but all the detected concentrations were similar and near the minimum detectable activity. Americium-241 was detected at three locations near the minimum detectable activity of approximately 0.07 pCi/L. The gamma spectrometry results detected cesium-137 in three samples, potassium-40 at eight locations, and radium-226 at one location. Mercury was below its maximum contaminant level of 2 µg/L in all samples. Gamma spectrometry results for the CFA production wells did not detect any analytes. Water-level measurements were taken from wells in the Idaho Nuclear Technology and Engineering Center, Central Facilities Area, and the area south of Central Facilities Area to evaluate groundwater flow directions. Water-level measurements indicated groundwater flow to the south-southwest from the Idaho Nuclear Technology and Engineering Center.« less

Quality of water and chemistry of bottom sediment in the Rillito Creek basin, Tucson, Arizona, 1992-93

USGS Publications Warehouse

Tadayon, Saeid

1995-01-01

Physical and chemical data were collected from four surface-water sites, six ground-water sites, and two bottom-sediment sites during 1992-93. Specific conductance, hardness, alkalinity, and dissolved- solids concentrations generally were higher in ground water than in surface water. The median concentrations of dissolved major ions, with the exception of potassium, were higher in ground water than in surface water. In surface water and ground water, calcium was the dominant cation, and bicarbonate was the dominant anion. Concentrations of dissolved nitrite and nitrite plus nitrate in surface water and ground water did not exceed the U.S. Environmental Protection Agency maximum contaminant levels of 1 and 10 milligrams per liter for drinking water, respectively. Ammonium plus organic nitrogen in bottom sediment was detected at the highest concentration of any nitrogen species. Median values for most of the dissolved trace elements in surface water and ground water were below the detection levels. Dissolved trace elements in surface water and ground water did not exceed the U.S. Environmental Protection Agency maximum contaminant levels for drinking water. Trace-element concentrations in bottom sediment were similar to trace-element concentrations reported for soils of the western conterminous United States. Several organochlorine pesticides and priority pollutants were detected in surface-water and bottom-sediment samples; however, they did not exceed water-quality standards. Pesticides or priority pollutants were not detected in ground-water samples.

Ground-Water Quality in the Delaware River Basin, New York, 2001 and 2005-2006

USGS Publications Warehouse

Nystrom, Elizabeth A.

2007-01-01

The Federal Clean Water Act Amendments of 1977 require that States monitor and report on the quality of ground water and surface water. To satisfy part of these requirements, the U.S. Geological Survey and New York State Department of Environmental Conservation have developed a program in which ground-water quality is assessed in 2 to 3 of New York State's 14 major basins each year. To characterize the quality of ground water in the Delaware River Basin in New York, water samples were collected from December 2005 to February 2006 from 10 wells finished in bedrock. Data from 9 samples collected from wells finished in sand and gravel in July and August 2001 for the National Water Quality Assessment Program also are included. Ground-water samples were collected and processed using standard U.S. Geological Survey procedures. Samples were analyzed for more than 230 properties and compounds, including physical properties, major ions, nutrients, trace elements, radon-222, pesticides and pesticide degradates, volatile organic compounds, and bacteria. Concentrations of most compounds were less than drinking-water standards established by the U.S. Environmental Protection Agency and New York State Department of Health; many of the organic analytes were not detected in any sample. Drinking-water standards that were exceeded at some sites include those for color, turbidity, pH, aluminum, arsenic, iron, manganese, radon-222, and bacteria. pH ranged from 5.6 to 8.3; the pH of nine samples was less than the U.S. Environmental Protection Agency secondary drinking-water standard range of 6.5 to 8.5. Water in the basin is generally soft to moderately hard (hardness 120 milligrams per liter as CaCO3 or less). The cation with the highest median concentration was calcium; the anion with the highest median concentrations was bicarbonate. Nitrate was the predominant nutrient detected but no sample exceeded the 10 mg/L U.S. Environmental Protection Agency maximum contaminant level. The trace elements detected with the highest median concentrations were strontium and iron in unfiltered water and strontium and barium in filtered water. Concentrations of trace elements in several samples exceeded U.S. Environmental Protection Agency secondary drinking-water standards, including aluminum (50-200 micrograms per liter, three wells), arsenic (10 micrograms per liter, one well), iron (300 micrograms per liter, three wells), and manganese (50 micrograms per liter, four wells). The median concentration of radon-222 was 1,580 picoCuries per liter. Radon-222 is not currently regulated, but the U.S. Environmental Protection Agency has proposed a maximum contaminant level of 300 picoCuries per liter along with an alternative maximum contaminant level of 4,000 picoCuries per liter, to be in effect in states that have programs to address radon in indoor air. Concentrations of radon-222 exceeded the proposed maximum contaminant level in all 19 of the samples and exceeded the proposed alternative maximum contaminant level in 1 sample. Eleven pesticides and pesticide degradates were detected in samples from ten wells; all were herbicides or herbicide degradates. Three volatile organic compounds were detected, including disinfection byproducts such as trichloromethane and gasoline components or additives such as methyl tert-butyl ether. No pesticides, pesticide degradates, or volatile organic compounds were detected above established limits. Coliform bacteria were detected in samples from five wells, four of which were finished in sand and gravel; Escherichia coli was not detected in any sample.

Phthalates in Commercial Chinese Rice Wines: Concentrations and the Cumulative Risk Assessment to Adult Males in Shanghai.

PubMed

Huang, Yue; Lu, Wen Wei; Chen, Bo; You, Jie; Wu, Min; Li, Shu Guang

2014-10-01

The concentrations of 16 phthalates in 164 commercial Chinese rice wines (CRW) were detected by GC-MS, and consumption data on CRW in different packaging types was investigated from 634 adult males in Shanghai using a food frequency questionnaire. Based on the principles of probabilistic modelling and cumulative risk assessment, the exposure and health risk of phthalates from CRW to adult males in Shanghai was evaluated. DMP, DEP, DIBP, DnBP, BBP, and DEHP were detected in the samples, the range of detection frequency of individual phthalates varied from 6.10% for BBP to 15.24% for DIBP, and the detected concentrations were 51.06-200.34 ng/mL. All the respondents consumed CRW, 90.69% of them consumed CRW 0.01-49.9 mL/d, the minimum value of the average daily intake of CRW was 6.25 mL/d, the median was 13.72 mL/d and the maximum was 300 mL/d. The median exposure level of the 6 detected Phthalates to adult males in Shanghai were 6.58-7.10 ng/(d•kg), and the maximum exposure level were 137.38-540.47 ng/(d•kg). The cumulative exposure health risk index (HI) based on the median and maximum exposure level of the 6 Phthalates (DMP, DEP, DIBP, DnBP, BBP, and DEHP) were 0.001147 and 0.063396, both were far less than 1. In conclusion, CRW were generally consumed by the adult males in Shanghai, although multiple phthalates were detected in commercial CRW, health risk of such exposure levels from commercial CRW to the target adult males in Shanghai was very low. Copyright © 2014 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

Pesticides and their metabolites in wells of Suffolk County, New York, 1998

USGS Publications Warehouse

Phillips, Patrick J.; Eckhardt, D.A.; Terracciano, S.A.; Rosenmann, Larry

1999-01-01

Five insecticide residues and 20 herbicide residues were detected in water samples collected from 50 shallow wells screened in the surficial sand and gravel aquifer in Suffolk County, Long Island in areas with known or suspected residues. Laboratory analytical methods with extremely low detection limits - from 0.001 to 0.2 ?g/L (micrograms per liter) - were used to analyze the samples for 60 pesticide residues. Forty-four of the samples contained at least one pesticide residue, and some samples contained as many as 11 different pesticides or pesticide metabolites. Only four water- quality standards were exceeded in the samples collected in this study. Dieldrin exceeded the New York State Class GA standard (0.004 ?g/L) in samples from eight wells. The Federal and New York State Maximum Contaminant Level for simazine (4 ?g/L) was exceeded in samples from two wells, and the State Class GA standard for simazine (0.5 ?g/L) was exceeded in samples from six wells. Federal water-quality standards have not been established for many of the compounds detected in this study, including herbicide metabolites. Maximum concentrations of four herbicide metabolites -metolachlor ESA (ethanesulfonic acid), metolachlor OA (oxanilic acid), and the alachlor metabolites alachlor ESA and alachlor OA -exceeded 20 ?g/L. The maximum concentration of one herbicide (tebuthiuron) exceeded 10 ?g/L, and the maximum concentration of three herbicides (simazine, metolachlor, and atrazine) and one herbicide metabolite (deisopropylatrazine) ranged from 1 to 10 ?g/L. The herbicide metolachlor, which is used on potato fields in Suffolk County, and its metabolites (metolachlor ESA and metolachlor OA) were most frequently detected in samples from agricultural areas. The herbicides simazine and tebuthiuron, which were used in utility rights-of-way, and the simazine metabolite deisopropylatrazine were detected at concentrations greater than 0.05 ?g/L most frequently in samples from residential and mixed land-use areas. The results of this investigation are not necessarily representative of conditions throughout the remainder of Long Island, because these samples were collected in areas of known or suspected residues.

Chemical and physical quality of selected public water supplies in Florida, August-September 1976

USGS Publications Warehouse

Irwin, G.A.; Healy, Henry G.

1978-01-01

Results of a 1976 water-quality reconnaissance made by the U.S. Geological Survey indicated that, with few exceptions, all public water supplies in Florida are of high quality and meet the standards set forth in the National Interim Primary Drinking Water Regulations. Occasionally the concentrations of fluoride, turbidity, cadmium, chromium, and lead approximated, equaled, or exceeded maximum contaminant levels with exceedences occurring very infrequently. The pesticides 2,4-D and silvex, were detected in some public supplies throughout the State mainly in surface water. Although pesticides were not detected in concentrations approaching the maximum levels established in the regulations, their presence does signal that the activities of man are beginning to affect some water resources. (Woodard-USGS)

Spacecraft Maximum Allowable Concentrations (SMACs) for C3 to C8 Aliphatic Saturated Aldehydes

NASA Technical Reports Server (NTRS)

Langford, Shannon D.

2007-01-01

Spacecraft maximum allowable concentrations (SMACs) for C3 to C8, straight-chain, aliphatic aldehydes have been previously assessed and have been documented in volume 4 of Spacecraft Maximum Allowable Concentrations for Selected Airborne Contaminants (James, 2000). These aldehydes as well as associated physical properties are shown in Table 1. The C3 to C8 aliphatic aldehydes can enter the habitable compartments and contaminate breathing air of spacecraft by several routes including incomplete oxidation of alcohols in the Environmental Control and Life Support System (ECLSS) air revitalization subsystem, as a byproduct of human metabolism, through materials off-gassing, or during food preparation. These aldehydes have been detected in the atmosphere of manned space vehicles in the past. Analysis performed by NASA of crew cabin air samples from the Russian Mir Space Station revealed the presence of C3 to C8 aldehydes at concentrations peaking at approximately 0.1 mg/cu m.

Water quality of streams in the Red River of the North Basin, Minnesota, North Dakota, and South Dakota, 1970-2001

USGS Publications Warehouse

Tornes, Lan H.

2005-01-01

Data for the Red River of the North (Red River) Basin in Minnesota, North Dakota, and South Dakota were analyzed to determine whether the water quality of streams in the basin is adequate to meet future needs. For the Red River at Emerson, Manitoba, site, pH values, water temperatures, and dissolved-oxygen concentrations generally were within the criteria established for the protection of aquatic life. Dissolved-solids concentrations ranged from 245 to 1,100 milligrams per liter. Maximum sulfate and chloride concentrations were near, but did not exceed, the established secondary maximum contaminant level. The trace elements considered potentially harmful generally were at concentrations that were less than the established guidelines, standards, and criteria. The concentrations of lead that were detected may have occurred as a result of sample contamination.  For the Red River upstream from Emerson, Manitoba, sites, pH and other field values rarely exceeded the criteria established for the protection of aquatic life. Many constituent concentrations for the Red River below Fargo, N. site exceeded water-quality guidelines, standards, and criteria. However, the trace-element exceedances could be natural or could be related to pollution or sample contamination. Many of the tributaries in the western part of the Red River Basin had median specific-conductance values that were greater than 1,000 microsiemens per centimeter. Sulfate concentrations occasionally exceeded the established drinking-water standard. Median arsenic concentrations were 6 micrograms per liter or less, and maximum concentrations rarely exceeded the 10-microgram-per-liter drinking-water standard that is scheduled to take effect in 2006. The small concentrations of lead, mercury, and selenium that occasionally were detected may have been a result of sample contamination or other factors. The tributaries in the eastern part of the Red River Basin had median specific-conductance values that were less than 1,000 microsiemens per centimeter.  Concentrations of pesticides that were detected and that had regulatory limits were less than the cited water-quality guidelines, standards, and criteria. Concentrations of compounds that were detected generally were less than the sediment- quality standards and criteria. The data considered in this report generally provide a good baseline from which to evaluate changes in water-quality conditions. However, because many of the trace elements detected, including lead and mercury, may have been the result of sample contamination, additional data are needed to confirm that trace-element concentrations generally are low. Concentrations of major ions, including sulfate, and specific conductance may continue to approach drinking-water standards during periods of low flow because the streams, particularly those in the western part of the basin, are sustained mostly by ground-water discharge that generally has large dissolved-solids concentrations.

Assessment of Potential Health Hazards During Emission of Hydrogen Sulphide from the Mine Exploiting Copper Ore Deposit - Case Study.

PubMed

Kupczewska-Dobecka, Małgorzata; Czerczak, Sławomir; Gromiec, Jan P; Konieczko, Katarzyna

2015-06-01

The aim of this study was to determine hydrogen sulphide concentration emitted from the mine extracting copper ore, to evaluate potential adverse health effects to the population living in four selected villages surrounding the exhaust shaft. Maximum measured concentration of hydrogen sulphide in the emitter is 286 µg/m³. Maximum emission calculated from the results of determinations of concentrations in the emitter is 0.44 kg/h. In selected villages hydrogen sulphide at concentrations exceeding 4 µg/m³ was not detected in any of the 5-hour air samples. In all locations, the estimated maximum 1-hour concentrations of hydrogen sulphide were below 1 µg/m³, and the estimated mean annual concentrations were below 0.53 µg/m³. Any risk to the health of people in the selected area is not expected. As indicated by the available data on the threshold odour, the estimated concentrations of hydrogen sulphide may be sensed by humans. Copyright© by the National Institute of Public Health, Prague 2015.

Water quality and possible sources of nitrate in the Cimarron Terrace Aquifer, Oklahoma, 2003

USGS Publications Warehouse

Masoner, Jason R.; Mashburn, Shana L.

2004-01-01

Water from the Cimarron terrace aquifer in northwest Oklahoma commonly has nitrate concentrations that exceed the maximum contaminant level of 10 milligrams per liter of nitrite plus nitrate as nitrogen (referred to as nitrate) set by the U.S. Environmental Protection Agency for public drinking water supplies. Starting in July 2003, the U.S. Geological Survey, in cooperation with the Oklahoma Department of Environmental Quality, conducted a study in the Cimarron terrace aquifer to assess the water quality and possible sources of nitrate. A qualitative and quantitative approach based on multiple lines of evidence from chemical analysis of nitrate, nitrogen isotopes in nitrate, pesticides (indicative of cropland fertilizer application), and wastewater compounds (indicative of animal or human wastewater) were used to indicate possible sources of nitrate in the Cimarron terrace aquifer. Nitrate was detected in 44 of 45 ground-water samples and had the greatest median concentration (8.03 milligrams per liter) of any nutrient analyzed. Nitrate concentrations ranged from <0.06 to 31.8 milligrams per liter. Seventeen samples had nitrate concentrations exceeding the maximum contaminant level of 10 milligrams per liter. Nitrate concentrations in agricultural areas were significantly greater than nitrate concentrations in grassland areas. Pesticides were detected in 15 of 45 ground-water samples. Atrazine and deethylatrazine, a metabolite of atrazine, were detected most frequently. Deethylatrazine was detected in water samples from 9 wells and atrazine was detected in samples from 8 wells. Tebuthiuron was detected in water samples from 5 wells; metolachlor was detected in samples from 4 wells; prometon was detected in samples from 4 wells; and alachlor was detected in 1 well. None of the detected pesticide concentrations exceeded the maximum contaminant level or health advisory level set by the U.S. Environmental Protection Agency. Wastewater compounds were detected in 28 of 45 groundwater samples. Of the 20 wastewater compounds detected, 11 compounds were from household chemicals, 3 compounds were hydrocarbons, 2 compounds were industrial chemicals, 2 compounds were pesticides, 1 compound was of animal source, and 1 compound was a detergent compound. The most frequently detected wastewater compound was phenol, which was detected in 23 wells. N,N-diethyl-meta-toluamide (DEET) was detected in water samples from 5 wells. Benzophenone, ethanol- 2-butoxy-phosphate, and tributylphosphate were detected in water samples from 3 wells. Fertilizer was determined to be the possible source of nitrate in samples from 13 of 45 wells sampled, with a15N values ranging from 0.43 to 3.46 permil. The possible source of nitrate for samples from the greatest number of wells (22 wells) was from mixed sources of nitrate from fertilizer, septic or manure, or natural sources. Mixed nitrate sources had a 15N values ranging from 0.25 to 9.83 permil. Septic or manure was determined as the possible source of nitrate in samples from 2 wells. Natural sources were determined to be the possible source of nitrate in samples from 7 wells, with a 15N values ranging from 0.83 to 9.44 permil.

Concentrations of nutrients, pesticides, and suspended sediment in the karst terrane of the Sinking Creek basin, Kentucky, 2004

USGS Publications Warehouse

Crain, Angela S.

2006-01-01

Water samples were collected in streams and springs in the karst terrane of the Sinking Creek Basin in 2004 as part of study in cooperation with the Kentucky Department of Agriculture. A total of 48 water samples were collected at 7 sites (4 springs, 2 streams, and 1 karst window) from April through November 2004. The karst terrane of the Sinking Creek Basin (also known as Boiling Spring Basin) encompasses about 125 square miles in Breckinridge County and portions of Meade and Hardin Counties in Kentucky. Fourteen pesticides were detected of the 52 pesticides analyzed in the stream and spring samples. Of the 14 detected pesticides, 12 were herbicides and 2 were insecticides. The most commonly detected pesticides?atrazine, simazine, metolachlor, and acetochlor?were those most heavily used on crops during the study. Atrazine was detected in 100 percent of all samples; simazine, metolachlor, and acetochlor were detected in more than 35 percent of all samples. The pesticide-transformation compound, deethylatrazine, was detected in 98 percent of the samples. Only one nonagricultural herbicide, prometon, was detected in more than 30 percent of the samples. Malathion, the most commonly detected insecticide, was found in 4 percent of the samples, which was followed by carbofuran (2 percent). Most of the pesticides were present in low concentrations; however, atrazine was found in springs exceeding the U.S. Environmental Protection Agency?s (USEPA) standards for drinking water. Atrazine exceeded the USEPA?s maximum contaminant level 2 times in 48 detections. Concentrations of nitrate greater than 10 milligrams per liter (mg/L) were not found in water samples from any of the sites. Concentrations of nitrite plus nitrate ranged from 0.21 to 3.9 mg/L at the seven sites. The median concentration of nitrite plus nitrate for all sites sampled was 1.5 mg/L. Concentrations of nitrite plus nitrate generally were higher in the springs than in the main stem of Sinking Creek. Forty-two percent of the concentrations of total phosphorus at all seven sites exceeded the USEPA?s recommended maximum concentration of 0.1 mg/L. The median concentration of total phosphorus for all sites sampled was 0.09 mg/L. The highest median concentrations of total phosphorus were found in the springs. Median concentrations of orthophosphate followed the same pattern as concentrations of total phosphorus in the springs. Concentrations of orthophosphate ranged from <0.006 to 0.192 mg/L. Concentrations of suspended sediment generally were low throughout the basin; the median concentration of suspended sediment for all sites sampled was 23 mg/L. The highest concentration of suspended sediment (1,486 mg/L) was measured following a storm event at Sinking Creek near Lodiburg, Ky.

Ground-water quality data in the north San Francisco Bay hydrologic provinces, California, 2004: Results from the California Ground-water Ambient Monitoring and Assessment (GAMA) program

USGS Publications Warehouse

Kulongoski, Justin T.; Belitz, Kenneth; Dawson, Barbara J.

2006-01-01

Ground-water samples were analyzed for major and minor ions, trace elements, nutrients, volatile organic compounds, pesticides and pesticide degradates, waste-water indicators, dissolved methane, nitrogen, carbon dioxide and noble gases (in collaboration with Lawrence Livermore National Laboratory). Naturally occurring isotopes (tritium, carbon-14, oxygen-18, deuterium and helium-4) also were measured in the samples to help identify the source and age of the ground water. Results show that no anthropogenic constituents were detected at concentrations higher than those levels set for regulatory purposes, and relatively few naturally-occurring constituents were detected at concentrations greater than regulatory levels. In this study, 21 of the 88 volatile organic compounds (VOCs) and gasoline additives and (or) oxygenates investigated were detected in ground-water samples, however, detected concentrations were one-half to one-forty-thousandth the maximum contaminant levels (MCL). Thirty-two percent of the randomized wells sampled had at least a single detection of a VOC or gasoline additive and (or) oxygenate. The most frequently detected compounds were chloroform, found in 12 of the 84 randomized wells; carbon disulfide, found in 8 of the 84 randomized wells; and toluene, found in 4 of the 84 randomized wells. Trihalomethanes were the most frequently detected class of VOCs. Nine of the 122 pesticides and (or) pesticide degradates investigated were detected in ground-water samples, however, concentrations were one-seventieth to one-eight-hundredth the MCLs. Seventeen percent of the randomized wells sampled had at least a single detection of pesticide and pesticide degradate. Herbicides were the most frequently detected class of pesticides. The most frequently detected compound was simazine, found in 8 of the 84 of the randomized wells. Chlordiamino-s-triazine and deisopropyl atrazine were both found in 2 of the 84 randomized wells sampled. Thirteen out of 63 compounds that may be indicative of the prescence of waste-water were detected in ground-water samples. Twenty-six percent of the randomized wells sampled for waste-water indicators had at least one detection. Isophorone was the most frequently detected in 6 of the 84 randomized wells. Bisphenol-A, caffeine, and indole each were detected in 3 of the 84 randomized wells. Major and minor ions and dissolved solids (DS) samples were collected at 33 public-supply wells; 3 samples had DS concentrations above the secondary maximum contaminant level (SMCL) of 500 mg/L. Ground-water samples from 32 public-supply wells were analyzed for trace elements. Arsenic concentrations above the MCL of 10 μg/L were measured at 4 public-supply wells, boron concentrations above the detection level for the purpose of reporting (DLR) of 100 μg/L were measured at 19 wells. Iron concentrations above the SMCL of 300 μg/L were measured at 7 wells, a lead concentration above the California notification level (NL) of 15 μg/L at one well, and manganese concentrations above the SMCL of 50 μg/L were measured at 17 wells. Vanadium concentrations above the DLR of 3 μg/L were measured at 9 public-supply wells; and chromium(VI) concentrations above the DLR of 1 μg/L were measured at 48 public-supply wells. Major and minor ions and dissolved solids (DS) samples were collected at 33 public-supply wells; 3 samples had DS concentrations above the secondary maximum contaminant level (SMCL) of 500 mg/L. Ground-water samples from 32 public-supply wells were analyzed for trace elements. Arsenic concentrations above the MCL of 10 μg/L were measured at 4 public-supply wells, boron concentrations above the detection level for the purpose of reporting (DLR) of 100 μg/L were measured at 19 wells. Iron concentrations above the SMCL of 300 μg/L were measured at 7 wells, a lead concentration above the California notification level (NL) of 15 μg/L at one well, and manganese concentrations above the SMCL of 50 μg/L were measured at 17 wells. Vanadium concentrations above the DLR of 3 μg/L were measured at 9 public-supply wells; and chromium(VI) concentrations above the DLR of 1 μg/L were measured at 48 public-supply wells. Microbial constituents were analyzed in 22 ground-water samples. Total coliform was detected in three wells. Counts ranged from 2 colonies per 100 mL to 20 colonies per 100 mL. MCLs for microbial constituents are based on reoccurring detection, and will be monitored during future sampling.

Ground-Water Quality in the Upper Susquehanna River Basin, New York, 2004-05

USGS Publications Warehouse

Hetcher-Aguila, Kari K.; Eckhardt, David A.V.

2006-01-01

Water samples were collected from 20 production wells and 13 private residential wells throughout the upper Susquehanna River Basin (upstream from the Pennsylvania border) during the fall of 2004 and the spring of 2005 and analyzed to describe the chemical quality of ground water in the upper basin. Wells were selected to represent areas of greatest ground-water use and highest vulnerability to contamination, and to provide a representative sampling from the entire (4,516 square-mile) upper basin. Samples were analyzed for physical properties, nutrients, inorganic constituents, metals, radionuclides, pesticides, volatile organic compounds, and bacteria. The cations that were detected in the highest concentrations were calcium, magnesium, and sodium; the anions that were detected in the greatest concentrations were bicarbonate, chloride, and sulfate. The predominant nutrient was nitrate, the concentrations of which were greater in samples from sand and gravel aquifers than in samples from bedrock. The metals barium, boron, cobalt, copper, and nickel were detected in every sample; the metals with the highest concentrations were barium, boron, iron, manganese, strontium, and lithium. The pesticide compounds detected most frequently were atrazine, deethylatrazine, alachlor ESA, and two degradation products of metolachlor (metolachlor ESA and metolachlor OA); the compounds detected in highest concentration were metolachlor ESA and OA. Volatile organic compounds were detected in 11 samples, and concentrations of 3 of these compounds exceeded 1 microgram per liter (?g/L). Methyl tert-butyl ether (MTBE), a gasollline additive, was not detected in any sample. Several analytes were found in concentrations that exceeded Federal and New York State water-quality standards, which are typically identical. Chloride concentrations exceeded the U.S. Environmental Protection Agency (USEPA) Secondary Maximum Contaminant Level (SMCL) of 250 milligrams per liter (mg/L) in two samples, and sulfate concentrations exceeded the SMCL of 250 mg/L in one sample. Sodium concentrations exceeded the USEPA Drinking Water Advisory of 60 mg/L in six samples. Nitrate concentrations exceeded the USEPA Maximum Contaminant Level (MCL) of 10 mg/L in one sample and approached this limit (at 9.84 mg/L) in another sample. Barium concentrations exceeded the MCL of 2,000 ?g/L in one sample. Iron concentrations exceeded the SMCL of 300 ?g/L in five samples, and manganese concentrations exceeded the SMCL of 50 ?g/L in 14 samples. Arsenic was detected in seven samples, and the MCL for arsenic (10 ?g/L) was exceeded in two samples. Radon-222 exceeded the proposed MCL of 300 picocuries per liter in 24 samples. Any detection of total coliform or fecal coliform bacteria is considered a violation of New York State health regulations; in this study, total coliform was detected in six samples and fecal coliform was detected in one sample, but Escherichia coli (E. coli) was not detected in any sample.

Examination of body burden and taint for Iceland scallop (Chlamys islandica) and American plaice (Hippoglossoides platessoides) near the Terra Nova offshore oil development over ten years of drilling on the Grand Banks of Newfoundland, Canada

NASA Astrophysics Data System (ADS)

DeBlois, Elisabeth M.; Kiceniuk, Joe W.; Paine, Michael D.; Kilgour, Bruce W.; Tracy, Ellen; Crowley, Roger D.; Williams, Urban P.; Gregory Janes, G.

2014-12-01

This paper presents results of analyses of body burdens of metals and hydrocarbons, and taste tests for taint, in Iceland scallop and American plaice performed as part of the Environmental Effects Monitoring (EEM) program for the Terra Nova offshore oil development (Grand Banks of Newfoundland, Canada). Scallop and plaice were collected in a Study Area located within approximately 1 km of drill centres at Terra Nova and in a Reference Area located approximately 20 km from the development. Samples were collected in 1997 to establish a baseline, and from 2000 to 2010, during drilling periods. Scallop adductor muscle tissue was contaminated with >C10-C21 aliphatic hydrocarbons resembling the drilling fluid in the synthetic drilling mud (SBM) used at Terra Nova in 2000, 2002 and 2004, but contamination of adductor muscle was not noted in 2006, 2008 and 2010. The maximum concentration in muscle was 28 mg/kg wet weight, noted in 2002. Scallop viscera was contaminated with hydrocarbons resembling drilling fluid in SBMs near drill centres in all EEM years except 2010. Viscera contamination with >C10-C21 hydrocarbons gradually decreased from a maximum of 150 mg/kg in 2000, to a maximum of 27 mg/kg in 2008; all values were below the laboratory reporting detection limit of 15 mg/kg in 2010. Therefore, evidence from both muscle and viscera indicates a decrease in tissue hydrocarbon contamination in recent years. Barium, another major constituent in drilling muds, has not been noted in scallop adductor muscles at concentrations above the reporting detection limit, but barium was detected in viscera in baseline and EEM years. The maximum concentration of barium in viscera during baseline sampling was 8 mg/kg. The maximum concentration in EEM years (29 mg/kg) was noted in 2000. The maximum concentration in 2010 was 25 mg/kg. The concentration of metals other than barium in scallop tissues was similar between the Terra Nova Study Area and the Reference Area. Hydrocarbons resembling the fluid in SBMs were noted in one American plaice liver sample collected near drill centres in 2000. Otherwise, there has been no evidence of project-related metals or hydrocarbon contamination in plaice liver or fillet samples. There has been no evidence of taint (off-taste) for scallop adductor muscle and plaice fillet tissue in baseline or EEM years. Combined with a parallel study on fish bioindicators at Terra Nova that showed that fish health at Terra Nova was similar to that at the Reference Area (Mathieu et al., 2011), these results indicate little to no detectable biological effects on Iceland scallop and American plaice as a result of Terra Nova activities.

Evaluation of polar organic micropollutants as indicators for wastewater-related coastal water quality impairment.

PubMed

Nödler, Karsten; Tsakiri, Maria; Aloupi, Maria; Gatidou, Georgia; Stasinakis, Athanasios S; Licha, Tobias

2016-04-01

Results from coastal water pollution monitoring (Lesvos Island, Greece) are presented. In total, 53 samples were analyzed for 58 polar organic micropollutants such as selected herbicides, biocides, corrosion inhibitors, stimulants, artificial sweeteners, and pharmaceuticals. Main focus is the application of a proposed wastewater indicator quartet (acesulfame, caffeine, valsartan, and valsartan acid) to detect point sources and contamination hot-spots with untreated and treated wastewater. The derived conclusions are compared with the state of knowledge regarding local land use and infrastructure. The artificial sweetener acesulfame and the stimulant caffeine were used as indicators for treated and untreated wastewater, respectively. In case of a contamination with untreated wastewater the concentration ratio of the antihypertensive valsartan and its transformation product valsartan acid was used to further refine the estimation of the residence time of the contamination. The median/maximum concentrations of acesulfame and caffeine were 5.3/178 ng L(-1) and 6.1/522 ng L(-1), respectively. Their detection frequency was 100%. Highest concentrations were detected within the urban area of the capital of the island (Mytilene). The indicator quartet in the gulfs of Gera and Kalloni (two semi-enclosed embayments on the island) demonstrated different concentration patterns. A comparatively higher proportion of untreated wastewater was detected in the gulf of Gera, which is in agreement with data on the wastewater infrastructure. The indicator quality of the micropollutants to detect wastewater was compared with electrical conductivity (EC) data. Due to their anthropogenic nature and low detection limits, the micropollutants are superior to EC regarding both sensitivity and selectivity. The concentrations of atrazine, diuron, and isoproturon did not exceed the annual average of their environmental quality standards (EQS) defined by the European Commission. At two sampling locations irgarol 1051 exceeded its annual average EQS value but not the maximum allowable concentration of 16 ng L(-1). Copyright © 2016 Elsevier Ltd. All rights reserved.

Measurement of peroxy radicals in the urban atmosphere by PERCA-LIF technique

NASA Astrophysics Data System (ADS)

Sadanaga, Y.; Matsumoto, J.; Sakurai, K.; Kato, S.; Nomaguchi, T.; Bandow, H.; Kajii, Y.

2002-12-01

A new instrument has been developed for measuring peroxy radicals (RO2) using the Chemical Amplifier-Laser Induced Fluorescence (PERCA-LIF) technique. RO2 was converted to NO2 via a chain reaction by the addition of NO and CO in a 1/4" Teflon tube. NO2 was detected by LIF using Nd:YAG laser (532 nm, 5W at 10kHz). More selective detection of NO2 is enabled by the LIF than by luminol chemiluminescence because of free from the interference by other oxidants when using luminol. LIF technique can be more sensitive detection of NO2 than the luminol detector. Optimum conditions were investigated by varying reaction time (i.e. the length of reaction tube) and the concentrations of NO and CO. Maximum chain length of approximately 300 was obtained in dry conditions using a H2O/O2 simultaneous photolysis method. Experiments were performed to characterize the dependence of the chain length on humidity for this instrument. In August 2002, RO2 measurements were performed in Osaka using this method. Maximum concentrations of RO2 in the daytime were approximately 100 pptv. Nighttime observations were also conducted and significant concentrations of RO2 were detected just after the sunset. Existence of formation processes in the dark condition was investigated.

Quality of water from shallow wells in the rice-growing area in southwestern Louisiana, 1999 through 2001

USGS Publications Warehouse

Tollett, Roland W.; Fendick, Robert B.

2004-01-01

In 1999-2001, the U.S. Geological Survey installed and sampled 27 shallow wells in the rice-growing area in southwestern Louisiana as part of the Acadian-Pontchartrain Study Unit of the National Water-Quality Assessment Program. The purpose of this report is to describe the waulity of water from shallow wells in the rice-growing area and to relate that water quality to natural and anthropogenic activities, particularly rice agriculture. Ground-water samples were analyzed for general ground-water properties and about 150 water-quality constituents, including major inorganic ions, trace elements, nutrients, dissolved organic carbon (DOC), pesticides, radon, chloroflourocarbons, and selected stable isotopes. Dissolved solids concentrations for 17 wells exceeded the U.S. Environmental Protection Agency secondary minimum containment level of 500 milligrams per liter (mg/L) for drinking water. Concentrations for major pesticides generally were less than the maximum contaminant levels for drinking water. Two major inorganic ions, sulfate and chloride, and two trace elements, iron and manganese, had concentrations that were greater than the secondary maximum containment levels. Three nutrient concentrations were greater than 2 mg/L, a level that might indicate contamination from human activities, and one nutrient concentration (that for nitrite plus nitrite as nitrogen) was greater than the maximum contaminant level of 10 mg/L for drinking water. The median concentration for DOC was 0.5 mg/L, indicating naturally-occurring DOC conditions in the study area. Thirteen pesticides and 7 pesticide degradation products were detected in 14 of the 27 wells sampled. Bentazon, 2, 4-D, and molinate (three rice herbicides) were detected in water from four, one, and one wells, respectively, and malathion (a rice insecticide) was deteced in water fromone well. Low-level concentrations and few detections of nutrients and pesticides indicated that ground-water quality was affected slightly by anthropogenic activities. Quality-control samples, including field blanks, replicates, and spikes, indicated no bias in ground-water data from collection on analysis. Radon concentrations for 22 of the 24 wells sampled wer at or greater than the U.S. Environmental Protection Agency proposed maximum contaminant level of 300 picocuries per liter. Chlorofluorocarbon concentrations in selected wells indicated the apparent ages of the ground water varied with depth water level and ranged from about 17 to 49 years. The stable isotopes of hydrogen and oxygen in water molecules indicated the origin of ground water in the study area was rainwater that originated near the study area and that few geochemical or physical processes influenced the stable isotopic composition of the shallow ground water. The Spearman rank correlation was used to detemrine whther significant correlations existed between physical properties, selected chemical constituents, the number of pesticides detected, and the apparent age of water. The depth to ground water was positively correlated to the well depth and inversely correlated to dissolved solids and other constituents, such as radon, indicating the ground water was under unconfined or semiconfined conditions and more dilute with increasing depth. As the depth to ground water increased, the concentrations of dissolved solids and other constituents decreased, possibly because the deeper sands had a greater transmittal of ground water, which, over time, would flush out, or dilute, the concentrations of dissolved solids in the natural sediments. The apparent age of water was correlated inversely with nitrite plus nitrite concentration, indicating that as apparent age increased, the nitrite plus nitrite concentration decreased. No significant correlations existed between the number of pesticides detected and any of the physical or chemica

Hydrogeology and ground-water quality of Valley Forge National Historical Park, Montgomery County, Pennsylvania

USGS Publications Warehouse

Sloto, Ronald A.; McManus, B. Craig

1996-01-01

Valley Forge National Historical Park is just southwest of the Commodore Semiconductor Group (CSG) National Priorities List (Superfund) Site, a source of volatile organic compounds (VOC's) in ground water. The 7.5-square-mile study area includes the part of the park in Lower Providence and West Norriton Townships in Montgomery County, Pa., and surrounding vicinity. The park is underlain by sedimentary rocks of the Upper Triassic age stockton Formation. A potentiometric-surface map constructed from water levels measured in 59 wells shows a cone of depression, approximately 0.5 mile in diameter, centered near the CSG Site. The cone of depression is caused by the pumping of six public supply wells. A ground-water divide between the cone of depression and Valley Forge National Historical Park provides a hydraulic barrier to the flow of ground water and contaminants from the CSG Site to the park. If pumping in the cone of depression was to cease, water levels would recover, and the ground-water divide would shift to the north. A hydraulic gradient between the CSG Site and the Schuylkill River would be established, causing contaminated ground water to flow to the park.Water samples were collected from 12 wells within the park boundary and 9 wells between the park boundary and the ground-water divide to the north of the park. All water samples were analyzed for physical properties (field determinations), nutrients, common ions, metals and other trace constituents, and VOC's. Water samples from the 12 wells inside the park boundary also were analyzed for pesticides. Concentrations of inorganic constituents in the water samples did not exceed U.S. Environmental Protection Agency maximum contaminant levels. Very low concentrations of organic compounds were detected in some of the water samples. VOC's were detected in water from 76 percent of the wells sampled; the maximum concentration detected was 5.8 micrograms per liter of chloroform. The most commonly detected VOC was chloroform. The second most commonly detected compound was methyl tert-butyl ether (MTBE), which was detected in water from 24 percent of wells sampled. Several pesticides were detected in water samples collected from within the park boundaries.: chlordane, DDD, dieldrin, endrin, heptachlor epoxide, and simazine. Concentrations of the detected pesticides were 0.1 micrograms per liter or less and did not exceed U.S. Environmental Protection Agency maximum contaminant levels.

A positive chemical ionization GC/MS method for the determination of airborne ethylene glycol and propylene glycols in non-occupational environments.

PubMed

Zhu, Jiping; Feng, Yong-Lai; Aikawa, Bio

2004-11-01

An analytical method for ethylene glycol and propylene glycols has been developed for measuring airborne levels of these chemicals in non-occupational environments such as residences and office buildings. The analytes were collected on charcoal tubes, solvent extracted, and analyzed by gas chromatography-mass spectrometry using a positive chemical ionization technique. The method had a method detection limit of 0.07 microg m(-3) for ethylene glycol and 0.03 microg m(-3) for 1,2- and 1,3-propylene glycols, respectively, based on a 1.44 m3 sampling volume. Indoor air samples of several residential homes and other indoor environments have been analyzed. The median concentrations of ethylene glycol and 1,2-propylene glycol in nine residential indoor air samples were 53 microg m(-3) and 13 microg m(-3) respectively with maximum values of 223 microg m(-3) and 25 microg m(-3) detected for ethylene glycol and 1,2-propylene glycol respectively. The concentrations of these two chemicals in one office and two laboratories were at low microg m(-3) levels. The maximum concentration of 1,3-propylene glycol detected in indoor air was 0.1 microg m(-3).

Quantifying the sources and sinks of nitrite in the oxygen minimum zone of the Eastern Tropical South Pacific

NASA Astrophysics Data System (ADS)

Ji, Qixing; Widner, Brittany; Jayakumar, Amal; Ward, Bess; Mulholland, Margaret

2017-04-01

In coastal upwelling regions, high surface productivity leads to high export and intense remineralization consuming oxygen. This, in combination with slow ventilation, creates oxygen minimum zones (OMZ) in eastern boundary regions of the ocean, such as the one off the Peruvian coast in the Eastern Tropical South Pacific. The OMZ is characterized by a layer of high nitrite concentration coinciding with water column anoxia. Sharp oxygen gradients are located above and below the anoxic layer (upper and lower oxyclines). Thus, the OMZ harbors diverse microbial metabolisms, several of which involve the production and consumption of nitrite. The sources of nitrite are ammonium oxidation and nitrate reduction. The sinks of nitrite include anaerobic ammonium oxidation (anammox), canonical denitrification and nitrite oxidation to nitrate. To quantify the sources and sinks of nitrite in the Peruvian OMZ, incubation experiments with 15N-labeled substrates (ammonium, nitrite and nitrate) were conducted on a research cruise in January 2015. The direct measurements of instantaneous nitrite production and consumption rates were compared with ambient nitrite concentrations to evaluate the turnover rate of nitrite in the OMZ. The distribution of nitrite in the water column showed a two-peak structure. A primary nitrite maximum (up to 0.5 μM) was located in the upper oxycline. A secondary nitrite maximum (up to 10 μM) was found in the anoxic layer. A nitrite concentration minimum occurred at the oxic-anoxic interface just below the upper oxycline. For the sources of nitrite, highest rates of ammonium oxidation and nitrate reduction were detected in the upper oxycline, where both nitrite and oxygen concentrations were low. Lower rates of nitrite production were detected within the layer of secondary nitrite maximum. For the sinks of nitrite, the rates of anammox, denitrification and nitrite oxidation were the highest just below the oxic-anoxic interface. Low nitrite consumption rates were also detected within the layer of the secondary nitrite maximum. The imbalances between nitrite production and consumption rates help to explain the distribution of nitrite in the water column. The primary nitrite maximum in the upper oxycline is consistent with ammonium oxidation exceeding nitrite oxidation. Nitrite consumption rates exceeding rates of nitrite production result in the low nitrite concentration at the oxic-anoxic interface. Within the secondary nitrite maximum in the anoxic layer, production and consumption of nitrite are equivalent within measurement error. These low turnover rates suggest the stability of the nitrite pool in the secondary nitrite maximum over long time scales (decades to millennial). These data could be implemented into biogeochemical models to decipher the origin and the evolution of nitrite distribution in the OMZs.

Limnological Conditions and Occurrence of Taste-and-Odor Compounds in Lake William C. Bowen and Municipal Reservoir #1, Spartanburg County, South Carolina, 2006-2009

USGS Publications Warehouse

Journey, Celeste A.; Arrington, Jane M.; Beaulieu, Karen M.; Graham, Jennifer L.; Bradley, Paul M.

2011-01-01

Limnological conditions and the occurrence of taste-and-odor compounds were studied in two reservoirs in Spartanburg County, South Carolina, from May 2006 to June 2009. Lake William C. Bowen and Municipal Reservoir #1 are relatively shallow, meso-eutrophic, warm monomictic, cascading impoundments on the South Pacolet River. Overall, water-quality conditions and phytoplankton community assemblages were similar between the two reservoirs but differed seasonally. Median dissolved geosmin concentrations in the reservoirs ranged from 0.004 to 0.006 microgram per liter. Annual maximum dissolved geosmin concentrations tended to occur between March and May. In this study, peak dissolved geosmin production occurred in April and May 2008, ranging from 0.050 to 0.100 microgram per liter at the deeper reservoir sites. Peak dissolved geosmin production was not concurrent with maximum cyanobacterial biovolumes, which tended to occur in the summer (July to August), but was concurrent with a peak in the fraction of genera with known geosmin-producing strains in the cyanobacteria group. Nonetheless, annual maximum cyanobacterial biovolumes rarely resulted in cyanobacteria dominance of the phytoplankton community. In both reservoirs, elevated dissolved geosmin concentrations were correlated to environmental factors indicative of unstratified conditions and reduced algal productivity, but not to nutrient concentrations or ratios. With respect to potential geosmin sources, elevated geosmin concentrations were correlated to greater fractions of genera with known geosmin-producing strains in the cyanobacteria group and to biovolumes of a specific geosmin-producing cyanobacteria genus (Oscillatoria), but not to actinomycetes concentrations. Conversely, environmental factors that correlated with elevated cyanobacterial biovolumes were indicative of stable water columns (stratified conditions), warm water temperatures, reduced nitrogen concentrations, longer residence times, and high phosphorus concentrations in the hypolimnion. Biovolumes of Cylindrospermopsis, Planktolyngbya, Synechococcus, Synechocystis, and Aphanizomenon correlated with the greater cyanobacteria biovolumes and were the dominant taxa in the cyanobacteria group. Related environmental variables were selected as input into multiple logistic regression models to evaluate the likelihood that geosmin concentrations could exceed the threshold level for human detection. In Lake William C. Bowen, the likelihood that dissolved geosmin concentrations exceeded the human detection threshold was estimated by greater mixing zone depths and differences in the 30-day prior moving window averages of overflow and flowthrough at Lake Bowen dam and by lower total nitrogen concentrations. At the R.B. Simms Water Treatment Plant, the likelihood that total geosmin concentrations in the raw water exceeded the human detection threshold was estimated by greater outflow from Reservoir #1 and lower concentrations of dissolved inorganic nitrogen. Overall, both models indicated greater likelihood that geosmin could exceed the human detection threshold during periods of lower nitrogen concentrations and greater water movement in the reservoirs.

Natural and anthropogenic radionuclide activity concentrations in the New Zealand diet.

PubMed

Pearson, Andrew J; Gaw, Sally; Hermanspahn, Nikolaus; Glover, Chris N

2016-01-01

To support New Zealand's food safety monitoring regime, a survey was undertaken to establish radionuclide activity concentrations across the New Zealand diet. This survey was undertaken to better understand the radioactivity content of the modern diet and also to assess the suitability of the current use of milk as a sentinel for dietary radionuclide trends. Thirteen radionuclides were analysed in 40 common food commodities, including animal products, fruits, vegetables, cereal grains and seafood. Activity was detected for (137)Caesium, (90)Strontium and (131)Iodine. No other anthropogenic radionuclides were detected. Activity concentrations of the three natural radionuclides of Uranium and the daughter radionuclide (210)Polonium were detected in the majority of food sampled, with a large variation in magnitude. The maximum activity concentrations were detected in shellfish for all these radionuclides. Based on the established activity concentrations and ranges, the New Zealand diet contains activity concentrations of anthropogenic radionuclides far below the Codex Alimentarius guideline levels. Activity concentrations obtained for milk support its continued use as a sentinel for monitoring fallout radionuclides in terrestrial agriculture. The significant levels of natural and anthropogenic radionuclide activity concentrations detected in finfish and molluscs support undertaking further research to identify a suitable sentinel for New Zealand seafood monitoring. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Water-quality assessment of the Rio Grande Valley, Colorado, New Mexico, and Texas; shallow ground-water quality of a land-use area in the San Luis Valley, south-central Colorado, 1993

USGS Publications Warehouse

Anderholm, S.K.

1996-01-01

This report describes the quality of shallow ground water in an agricultural area in the San Luis Valley, Colorado, and discusses how natural and human factors affect the quality of shallow ground water. Thirty-five wells were installed, and water samples were collected from these wells and analyzed for selected dissolved common constituents, nutrients, trace elements, radionuclides, and synthetic organic compounds. The San Luis Valley is a high intermontane valley that is partially drained by the Rio Grande. The San Luis Valley land-use study area was limited to a part of the valley where the depth to water is generally less than 25 feet. The area where the 35 monitor wells were installed was further limited to the part of the study area where center-pivot overhead sprinklers are used to irrigate crops. Precipitation, runoff from adjacent mountainous areas, and ground-water inflow from the adjacent mountainous areas are the main sources of water to the aquifers in the San Luis Valley. Discharge of water from the shallow, unconfined aquifer in the valley is mainly from evapotranspiration. The dominant land use in the San Luis Valley is agriculture, although nonirrigated land and residential land are interspersed with agricultural land. Alfalfa, native hay, barley, wheat, potatoes, and other vegetables are the main crops. Dissolved-solids concentrations in shallow ground water sampled ranged from 75 to 1,960 milligrams per liter. The largest median concentration of cations was for calcium, and the largest median concentration of anions was for bicarbonate in shallow ground water in the San Luis Valley. Calcium concentrations ranged from 7.5 to 300 milligrams per liter, and bicarbonate concentrations ranged from 28 to 451 milligrams per liter. Nitrite plus nitrate concentrations ranged from less than 0.1 to 58 milligrams per liter as N; water from 11 wells had nitrite plus nitrate concentrations greater than 10 milligrams per liter as N. With the exception of the following trace elements--aluminum, barium, iron, manganese, molybdenum, and uranium--the concentrations of trace elements were less than 10 micrograms per liter in 90 percent of the samples. All trace-element concentrations measured were below the maximum contaminant levels set by the U.S. Environmental Protection Agency. Five samples exceeded the proposed maximum contaminant level of 0.02 milligram per liter for uranium. All samples collected exceeded the proposed maximum contaminant level for radon-222. The volatile organic compound methyltertbutylether was detected in one sample at a concentration of 0.6 microgram per liter. Of the pesticides analyzed for, one or more were detected in water from 5 of the 35 wells sampled. Metribuzin was the most commonly detected pesticide and was detected in water from three wells at concentrations ranging from an estimated 0.005 to 0.017 microgram per liter. Metolachlor (detected in one sample at a concentration of 0.072 microgram per liter), prometon (detected in one sample at a concentration of 0.01 microgram per liter), and p,p'-DDE (detected in one sample at an estimated concentration of 0.002 microgram per liter) were the other pesticides detected. The U.S. Environmental Protection Agency lifetime health advisory for metolachlor, metribuzin, and prometon is 100 micrograms per liter, which is much larger than the concentrations measured in the shallow ground water sampled for this study. The elevated nitrite plus nitrate concentrations in shallow ground water are indicative of leaching of fertilizers from the land surface. This conclusion is consistent with conclusions made in other investigations of the San Luis Valley. On the basis of areal distribution and range of trace-element concentrations, human activities have not caused widespread trace-element contamination in the shallow grou

Arsenic in ground water in selected parts of southwestern Ohio, 2002-03

USGS Publications Warehouse

Thomas, Mary Ann; Schumann, Thomas L.; Pletsch, Bruce A.

2005-01-01

Arsenic concentrations were measured in 57 domestic wells in Preble, Miami, and Shelby Counties, in southwestern Ohio. The median arsenic concentration was 7.1 ?g/L (micrograms per liter), and the maximum was 67.6 ?g/L. Thirty-seven percent of samples had arsenic concentrations greater than the U.S. Environmental Protection Agency drinking-water standard of 10 ?g/L. Elevated arsenic concentrations (>10 ?g/L) were detected over the entire range of depths sampled (42 to 221 feet) and in each of three aquifer types, Silurian carbonate bedrock, glacial buried-valley deposits, and glacial till with interbedded sand and gravel. One factor common in all samples with elevated arsenic concentrations was that iron concentrations were greater than 1,000 ?g/L. The observed correlations of arsenic with iron and alkalinity are consistent with the hypothesis that arsenic was released from iron oxides under reducing conditions (by reductive dissolution or reductive desorption). Comparisons among the three aquifer types revealed some differences in arsenic occurrence. For buried-valley deposits, the median arsenic concentration was 4.6 ?g/L, and the maximum was 67.6 ?g/L. There was no correlation between arsenic concentrations and depth; the highest concentrations were at intermediate depths (about 100 feet). Half of the buried-valley samples were estimated to be methanic. Most of the samples with elevated arsenic concentrations also had elevated concentrations of dissolved organic carbon and ammonia. For carbonate bedrock, the median arsenic concentration was 8.0 ?g/L, and the maximum was 30.7 ?g/L. Arsenic concentrations increased with depth. Elevated arsenic concentrations were detected in iron- or sulfate-reducing samples. Arsenic was significantly correled with molybdenum, strontium, fluoride, and silica, which are components of naturally ocurring minerals. For glacial till with interbedded sand and gravel, half of the samples had elevated arsenic concentrations. The median was 11.4 ?g/L, and the maximum was 27.6 ?g/L. At shallow depths (<100 feet), this aquifer type had higher arsenic and iron concentrations than carbonate bedrock. It is not known whether these observed differences among aquifer types are related to variations in (1) arsenic content of the aquifer material, (2) organic carbon content of the aquifer material, (3) mechanisms of arsenic mobilization (or uptake), or (4) rates of arsenic mobilization (or uptake). A followup study that includes solid-phase analyses and geochemical modeling was begun in 2004 in northwestern Preble County.

Anthropogenic Organic Compounds in Source and Finished Groundwater of Community Water Systems in the Piedmont Physiographic Province, Potomac River Basin, Maryland and Virginia, 2003-04

USGS Publications Warehouse

Banks, William S.L.; Reyes, Betzaida

2009-01-01

A source- and finished-water-quality assessment of groundwater was conducted in the Piedmont Physiographic Province of Maryland and Virginia in the Potomac River Basin during 2003-04 as part of the U.S. Geological Survey's National Water-Quality Assessment Program. This assessment used a two-phased approach to sampling that allowed investigators to evaluate the occurrence of more than 280 anthropogenic organic compounds (volatile organic compounds, pesticides and pesticide degradates, and other anthropogenic organic compounds). Analysis of waters from 15 of the largest community water systems in the study area were included in the assessment. Source-water samples (raw-water samples collected prior to treatment) were collected at the well head. Finished-water samples (raw water that had been treated and disinfected) were collected after treatment and prior to distribution. Phase one samples, collected in August and September 2003, focused on source water. Phase two analyzed both source and finished water, and samples were collected in August and October of 2004. The results from phase one showed that samples collected from the source water for 15 community water systems contained 92 anthropogenic organic compounds (41 volatile organic compounds, 37 pesticides and pesticide degradates, and 14 other anthropogenic organic compounds). The 5 most frequently occurring anthropogenic organic compounds were detected in 11 of the 15 source-water samples. Deethylatrazine, a degradate of atrazine, was present in all 15 samples and metolachlor ethanesulfonic acid, a degradate of metolachlor, and chloroform were present in 13 samples. Atrazine and metolachlor were present in 12 and 11 samples, respectively. All samples contained a mixture of compounds with an average of about 14 compounds per sample. Phase two sampling focused on 10 of the 15 community water systems that were selected for resampling on the basis of occurrence of anthropogenic organic compounds detected most frequently during the first phase. A total of 48 different anthropogenic organic compounds were detected in samples collected from source and finished water. There were a similar number of compounds detected in finished water (41) and in source water (39). The most commonly detected group of anthropogenic organic compounds in finished water was trihalomethanes - compounds associated with the disinfection of drinking water. This group of compounds accounted for 30 percent of the detections in source water and 44 percent of the detections in finished water, and were generally found in higher concentrations in finished water. Excluding trihalomethanes, the number of total detections was about the same in source-water samples (33) as it was in finished-water samples (35). During both phases of the study, two measurements for human-health assessment were used. The first, the Maximum Contaminant Level for drinking water, is set by the U.S. Environmental Protection Agency and represents a legally enforceable maximum concentration of a contaminant permitted in drinking water. The second, the Health-Based Screening Level, was developed by the U.S. Geological Survey, is not legally enforceable, and represents a limit for more chronic exposures. Maximum concentrations for each detected compound were compared with either the Maximum Contaminant Level or the Health-Based Screening Level when available. More than half of the compounds detected had either a Maximum Contaminant Level or a Health-Based Screening Level. A benchmark quotient was set at 10 percent (greater than or equal to 0.1) of the ratio of the detected concentration of a particular compound to its Maximum Contaminant Level, or Health-Based Screening Level. This was considered a threshold for further monitoring. During phase one, when only source water was sampled, seven compounds (chloroform, benzene, acrylonitrile, methylene chloride, atrazine, alachlor, and dieldrin) met or exceeded a benchmark quotient. No de

Summary and evaluation of pesticides in field blanks collected for the National Water-Quality Assessment Program, 1992-95

USGS Publications Warehouse

Martin, Jeffrey D.; Gilliom, Robert J.; Schertz, Terry L.

1999-01-01

Field blanks did show evidence of contamination by some pesticides. Most of the pesticides detected in field blanks, however, were detected more frequently and at higher concentrations in environmental water samples. Two criteria were used to evaluate the need to consider contamination in water-quality assessments: (1) a ratio of the frequency of pesticide detection in environmental water samples to the frequency of detection in field blanks of 5.0 or less and (2) a ratio of the median concentration detected in environmental water samples to the maximum concentration detected in field blanks of 2.0 or less. These criteria indicate that contamination, for the majority of the pesticide data collected for the NAWQA Program, probably does not need to be considered in the analysis and interpretation of (1) the frequency of pesticide detection or (2) the median concentration of pesticides detected. Contamination must be considered, however, in detection frequency for cispermethrin, pronamide, p,p' -DDE, pebulate, propargite, ethalfluralin, and triallate in surface water and fenuron, benfluralin, pronamide, cis-permethrin, triallate, chlorpyrifos, trifluralin, propanil, p,p' -DDE, bromacil, dacthal, diazinon, and diuron in ground water. Contamination also must be considered in median concentrations detected for pronamide, p,p' -DDE, propargite, napropamide, and triallate in surface water and benfluralin, cis-permethrin, triallate, chlorpyrifos, trifluralin, p,p' -DDE, dacthal, and diazinon in ground water.

Simulated ground-water flow and water quality of the Mississippi River alluvium near Burlington, Iowa, 1999

USGS Publications Warehouse

Boyd, Robert A.

2001-01-01

Water samples collected from the alluvium indicated ground water can be classified as a calcium-magnesium-bicarbonate type. Reducing conditions likely occur in some localized areas of the alluvium, as suggested by relatively large concentrations of dissolved iron (4,390 micrograms per liter) and manganese (2, 430 micrograms per liter) in some ground-water samples. Nitrite plus nitrate was detected at concentrations greater than or equal to 8 milligrams per liter in three samples collected from observation wells completed in close proximity to cropland; the nitrite plus nitrate concentration in one groundwater sample exceeded the U.S. Environmental Protection Agency Maximum Contaminant Level for nitrate in drinking water (10 milligrams per liter as N). Triazine herbicides (atrazine, cyanazine, propazine, simazine, and selected degradation products) and chloroacetanilide herbicides (acetochlor, alachlor, and metolachlor) were detected in some water samples. A greater number of herbicide compounds were detected in surface-water samples than in ground-water samples. Herbicide concentrations typically were at least an order of magnitude greater in surfacewater samples than in ground-water samples. The Maximum Contaminant Level for alachlor (2 micrograms per liter) was exceeded in a sample from Dry Branch Creek at Tama Road and for atrazine (3 micrograms per liter) was exceeded in samples collected from Dry Branch Creek at Tama Road and the county drainage ditch at Tama Road.

A rapid approach for measuring silver nanoparticle concentration and dissolution in seawater by UV-Vis.

PubMed

Sikder, Mithun; Lead, Jamie R; Chandler, G Thomas; Baalousha, Mohammed

2018-03-15

Detection and quantification of engineered nanoparticles (NPs) in environmental systems is challenging and requires sophisticated analytical equipment. Furthermore, dissolution is an important environmental transformation process for silver nanoparticles (AgNPs) which affects the size, speciation and concentration of AgNPs in natural water systems. Herein, we present a simple approach for the detection, quantification and measurement of dissolution of PVP-coated AgNPs (PVP-AgNPs) based on monitoring their optical properties (extinction spectra) using UV-vis spectroscopy. The dependence of PVP-AgNPs extinction coefficient (ɛ) and maximum absorbance wavelength (λ max ) on NP size was experimentally determined. The concentration, size, and extinction spectra of PVP-AgNPs were characterized during dissolution in 30ppt synthetic seawater. AgNPs concentration was determined as the difference between the total and dissolved Ag concentrations measured by inductively coupled plasma-mass spectroscopy (ICP-MS); extinction spectra of PVP-AgNPs were monitored by UV-vis; and size evolution was monitored by atomic force microscopy (AFM) over a period of 96h. Empirical equations for the dependence of maximum absorbance wavelength (λ max ) and extinction coefficient (ɛ) on NP size were derived. These empirical formulas were then used to calculate the size and concentration of PVP-AgNPs, and dissolved Ag concentration released from PVP-AgNPs in synthetic seawater at variable particle concentrations (i.e. 25-1500μgL -1 ) and in natural seawater at particle concentration of 100μgL -1 . These results suggest that UV-vis can be used as an easy and quick approach for detection and quantification (size and concentration) of sterically stabilized PVP-AgNPs from their extinction spectra. This approach can also be used to monitor the release of Ag from PVP-AgNPs and the concurrent NP size change. Finally, in seawater, AgNPs dissolve faster and to a higher extent with the decrease in NP concentration toward environmentally relevant concentrations. Copyright © 2017 Elsevier B.V. All rights reserved.

Factors controlling spatial and temporal patterns of multiple pesticide compounds in groundwater (Hesbaye chalk aquifer, Belgium).

PubMed

Hakoun, Vivien; Orban, Philippe; Dassargues, Alain; Brouyère, Serge

2017-04-01

Factors governing spatial and temporal patterns of pesticide compounds (pesticides and metabolites) concentrations in chalk aquifers remain unclear due to complex flow processes and multiple sources. To uncover which factors govern pesticide compound concentrations in a chalk aquifer, we develop a methodology based on time series analyses, uni- and multivariate statistics accounting for concentrations below detection limits. The methodology is applied to long records (1996-2013) of a restricted compound (bentazone), three banned compounds (atrazine, diuron and simazine) and two metabolites (deethylatrazine (DEA) and 2,6-dichlorobenzamide (BAM)) sampled in the Hesbaye chalk aquifer in Belgium. In the confined area, all compounds had non-detects fractions >80%. By contrast, maximum concentrations exceeded EU's drinking-water standard (100 ng L -1 ) in the unconfined area. This contrast confirms that recent recharge and polluted water did not reach the confined area, yet. Multivariate analyses based on variables representative of the hydrogeological setting revealed higher diuron and simazine concentrations in the southeast of the unconfined area, where urban activities dominate land use and where the aquifer lacks protection from a less permeable layer of hardened chalk. At individual sites, positive correlations (up to τ=0.48 for bentazone) between pesticide compound concentrations and multi-annual groundwater level fluctuations confirm occurrences of remobilization. A downward temporal trend of atrazine concentrations likely reflects decreasing use of this compound over the last 28 years. However, the lack of a break in concentrations time series and maximum concentrations of atrazine, simazine, DEA and BAM exceeding EU's standard post-ban years provide evidence of persistence. Contrasting upward trends in bentazone concentrations show that a time lag is required for restriction measures to be efficient. These results shed light on factors governing pesticide compound concentrations in chalk aquifers. The developed methodology is not restricted to chalk aquifers, it could be transposed to study other pollutants with concentrations below detection limits. Copyright © 2017 Elsevier Ltd. All rights reserved.

Pharmacokinetics of tilmicosin in equine tissues and plasma.

PubMed

Clark, C; Dowling, P M; Ross, S; Woodbury, M; Boison, J O

2008-02-01

The macrolide antibiotic tilmicosin has potential for treating bacterial respiratory tract infections in horses. A pharmacokinetic study evaluated the disposition of tilmicosin in the horse after oral (4 mg/kg) or subcutaneous (s.c.) (10 mg/kg) administration. Tilmicosin was not detected in equine plasma or tissues after oral administration at this dose. With s.c. injection, tilmicosin concentrations reached a maximum concentration of approximately 200 ng/mL in the plasma of the horses. Tilmicosin concentrations in plasma persisted with a mean residence time (MRT) of 19 h. Maximum tissue residue concentrations (C(max)) of tilmicosin measured in equine lung, kidney, liver and muscle tissues after s.c. administration were 2784, 4877, 1398, and 881 ng/g, respectively. The MRT of tilmicosin in these tissues was approximately 27 h. Subcutaneous administration of tilmicosin resulted in severe reactions at the injection sites.

Ground-Water Quality in the Genesee River Basin, New York, 2005-2006

USGS Publications Warehouse

Eckhardt, David A.V.; Reddy, J.E.; Tamulonis, Kathryn L.

2007-01-01

Water samples were collected from 7 community water system wells and 15 private domestic wells throughout the Genesee River Basin in New York State (downstream from the Pennsylvania border) from October 2005 through March 2006 and analyzed to characterize the chemical quality of ground water in the basin. The wells were selected to represent areas of greatest ground-water use and to provide a representative sampling from the 2,439 square-mile basin area in New York. Samples were analyzed for five physical properties and 226 constituents that included nutrients, major inorganic ions, trace elements, radionuclides, pesticides, volatile organic compounds, and bacteria. The results show that ground water used for drinking water is generally of good quality in the Genesee River Basin, although concentrations of seven constituents exceeded drinking water standards. The cations that were detected in the highest concentrations were calcium, magnesium, and sodium; the anions that were detected in the greatest concentrations were bicarbonate, chloride, and sulfate. The predominant nutrient was nitrate, and nitrate concentrations were greater in samples from sand and gravel aquifers than in samples from bedrock aquifers. The trace elements barium, boron, cobalt, copper, and nickel were detected in every sample; the highest concentrations were barium, boron, chromium, iron, manganese, strontium, and lithium. Fourteen pesticides including seven pesticide degradates were detected in water from 12 of the 22 wells, but none of the concentrations exceeded Maximum Contaminant Levels (MCLs). Eight volatile organic compounds (VOCs) were detected in six samples, but none of the concentrations exceeded MCLs. Seven chemical analytes and three types of bacteria were present in concentrations that exceeded Federal and New York State water-quality standards, which are typically identical. Sulfate concentrations exceeded the U.S. Environmental Protection Agency (USEPA) Secondary Maximum Contaminant Level (SMCL) of 250 milligrams per liter (mg/L) in three samples; the chloride SMCL (250 mg/L) was exceeded in one sample. Sodium concentrations exceeded the USEPA Drinking Water Health Advisory of 60 mg/L in five samples. The SMCL for iron (300 ug/L) was exceeded in 11 filtered samples; the USEPA SMCL for manganese (50 ug/L) was exceeded in 10 filtered samples, and the New York State MCL (300 ug/L) was exceeded in 1 filtered sample. The MCL for aluminum (200 ug/L) was exceeded in 1 sample, and the MCL for arsenic (10 ug/L) was exceeded in 1 sample. Radon-222 exceeded the proposed USEPA MCL of 300 picocuries per liter in 16 samples. Any detection of total coliform or fecal coliform bacteria is considered a violation of New York State health regulations; in this study, total coliform was detected in eight samples; fecal coliform was detected in two samples, and Escherichia coli was detected in one sample.

Widespread detection of N,N-diethyl-m-toluamide in U.S. streams: Comparison with concentrations of pesticides, personal care products, and other organic wastewater compounds

USGS Publications Warehouse

Sandstrom, M.W.; Kolpin, D.W.; Thurman, E.M.; Zaugg, S.D.

2005-01-01

One of the most frequently detected organic chemicals in a nationwide study concerning the effects of wastewater on stream water quality conducted in the year 2000 was the widely used insect repellant N,N-diethyl-m-toluamide (DEET). It was detected at levels of 0.02 μg/L or greater in 73% of the stream sites sampled, with the selection of sampling sites being biased toward streams thought to be subject to wastewater contamination (i.e., downstream from intense urbanization and livestock production). Although DEET frequently was detected at all sites, the median concentration was low (0.05 μg/L). The highest concentrations of DEET were found in streams from the urban areas (maximum concentration, 1.1 μg/L). The results of the present study suggest that the movement of DEET to streams through wastewater-treatment systems is an important mechanism that might lead to the exposure of aquatic organisms to this chemical.

Occurrence of waterborne pathogens and Escherichia coli at offshore drinking water intakes in lake Ontario.

PubMed

Edge, T A; Khan, I U H; Bouchard, R; Guo, J; Hill, S; Locas, A; Moore, L; Neumann, N; Nowak, E; Payment, P; Yang, R; Yerubandi, R; Watson, S

2013-10-01

The occurrence of waterborne pathogens was investigated at three drinking water intakes located about 2 km offshore in Lake Ontario. Water sampling was conducted over 3 years for Campylobacter spp., Cryptosporidium spp., Giardia spp., cultivable enteric viruses, and water quality parameters. All pathogens were detected in the offshore source water for each water treatment plant (WTP1 to WTP3), although at relatively low frequencies and concentrations. Giardia was the most common pathogen, occurring in 36% of water samples from the influent of WTP1 (n = 46), and with a maximum concentration of 0.70 cysts/liter in this influent. Cryptosporidium occurred as frequently as 15% in the WTP2 influent (n = 35), with a maximum concentration of 0.40 oocysts/liter in the WTP1 influent. The human Bacteroidales HF183 DNA marker was most common in the WTP1 influent (19%), and this was the only WTP where the Cryptosporidium hominis genotype was detected. No water quality parameter was predictive of pathogen occurrence across all three WTP influents. Escherichia coli was often below detection when pathogens were detected, and spikes in E. coli concentrations often did not coincide with pathogen occurrence. After summer rain events, river plumes had E. coli concentrations as high as 222 CFU/100 ml in surface waters 2 km offshore, without impacting drinking water intakes below the thermocline on the lake bottom. At times, prechlorination to control mussels at offshore intake cribs compromised the use of E. coli for "raw" water quality assessment, particularly for chlorine-resistant Cryptosporidium. E. coli measured by standard methods did not reliably predict pathogen occurrence at drinking water intakes in offshore ecosystems.

Occurrence of Waterborne Pathogens and Escherichia coli at Offshore Drinking Water Intakes in Lake Ontario

PubMed Central

Khan, I. U. H.; Bouchard, R.; Guo, J.; Hill, S.; Locas, A.; Moore, L.; Neumann, N.; Nowak, E.; Payment, P.; Yang, R.; Yerubandi, R.; Watson, S.

2013-01-01

The occurrence of waterborne pathogens was investigated at three drinking water intakes located about 2 km offshore in Lake Ontario. Water sampling was conducted over 3 years for Campylobacter spp., Cryptosporidium spp., Giardia spp., cultivable enteric viruses, and water quality parameters. All pathogens were detected in the offshore source water for each water treatment plant (WTP1 to WTP3), although at relatively low frequencies and concentrations. Giardia was the most common pathogen, occurring in 36% of water samples from the influent of WTP1 (n = 46), and with a maximum concentration of 0.70 cysts/liter in this influent. Cryptosporidium occurred as frequently as 15% in the WTP2 influent (n = 35), with a maximum concentration of 0.40 oocysts/liter in the WTP1 influent. The human Bacteroidales HF183 DNA marker was most common in the WTP1 influent (19%), and this was the only WTP where the Cryptosporidium hominis genotype was detected. No water quality parameter was predictive of pathogen occurrence across all three WTP influents. Escherichia coli was often below detection when pathogens were detected, and spikes in E. coli concentrations often did not coincide with pathogen occurrence. After summer rain events, river plumes had E. coli concentrations as high as 222 CFU/100 ml in surface waters 2 km offshore, without impacting drinking water intakes below the thermocline on the lake bottom. At times, prechlorination to control mussels at offshore intake cribs compromised the use of E. coli for “raw” water quality assessment, particularly for chlorine-resistant Cryptosporidium. E. coli measured by standard methods did not reliably predict pathogen occurrence at drinking water intakes in offshore ecosystems. PMID:23835181

Ethyl glucuronide, ethyl sulfate, and ethanol in urine after sustained exposure to an ethanol-based hand sanitizer.

PubMed

Reisfield, Gary M; Goldberger, Bruce A; Crews, Bridgit O; Pesce, Amadeo J; Wilson, George R; Teitelbaum, Scott A; Bertholf, Roger L

2011-03-01

To assess the degree of ethanol absorption and subsequent formation of urinary ethyl glucuronide (EtG) and ethyl sulfate (EtS) following sustained application of hand sanitizer, 11 volunteers cleansed their hands with Purell(™) hand sanitizer (62% ethanol) every 5 min for 10 h on three consecutive days. Urine specimens were obtained at the beginning and end of each day of the study, and on the morning of the fourth day. Urinary creatinine, ethanol, EtG, and EtS concentrations were measured. EtG was undetectable in all pre-study urine specimens, but two pre-study specimens had detectable EtS (73 and 37 ng/mL). None of the pre-study specimens had detectable ethanol. The maximum EtG and EtS concentrations over the course of the study were 2001 and 84 ng/mL, respectively, and nearly all EtG- and EtS-positive urine specimens were collected at the conclusion of the individual study days. Only two specimens had detectable EtG at the beginning of any study day (96 and 139 ng/mL), and only one specimen had detectable EtS at the beginning of a study day (64 ng/mL), in addition to the two with detectable EtS prior to the study. Creatinine-adjusted maximum EtG and EtS concentrations were 1998 and 94 μg/g creatinine, respectively. In patients being monitored for ethanol use by urinary EtG concentrations, currently accepted EtG cutoffs do not distinguish between ethanol consumption and incidental exposures, particularly when urine specimens are obtained shortly after sustained use of ethanolcontaining hand sanitizer. Our data suggest that EtS may be an important complementary biomarker in distinguishing ethanol consumption from dermal exposure.

Nutrients and organic compounds in Deer Creek and south branch Plum Creek in southwestern Pennsylvania, April 1996 through September 1998

USGS Publications Warehouse

Williams, D.R.; Clark, M.E.

2001-01-01

This report presents results of an analysis of nutrient and pesticide data from two surface-water sites and volatile organic compound (VOC) data from one of the sites that are within the Allegheny and Monongahela River Basins study unit of the National Water-Quality Assessment Program of the U.S. Geological Survey. The Deer Creek site was located in a 27.0 square-mile basin within the Allegheny River Basin in Allegheny County. The primary land uses consist of small urban areas, large areas of residential housing, and some agricultural land in the upper part of the basin. The South Branch Plum Creek site was located in a 33.3 square-mile basin within the Allegheny River Basin in Indiana County. The primary land uses throughout this basin are mostly agriculture and forestland.Water samples for analysis of nutrients were collected monthly and during high-flow events from April 1996 through September 1998. Concentrations of dissolved nitrite, dissolved ammonia plus organic nitrogen, and dissolved phosphorus were less than the method detection limits in more than one-half of the samples collected. The median concentration of dissolved nitrite plus nitrate in South Branch Plum Creek was 0.937 mg/L and 0.597 mg/L in Deer Creek. The median concentration of dissolved orthophosphate was 0.01 mg/L in both streams. High loads of nitrate were measured in both streams from March to June. Concentrations of dissolved ammonia nitrogen, dissolved nitrate, and total phosphorus were lower during the summer months. Measured concentrations of nitrate nitrogen in both streams were well below the U.S. Environmental Protection Agency (USEPA) maximum contaminant level (MCL) of 10 mg/L.Water samples for analysis of pesticides were collected throughout 1997 in both streams and during a storm event on August 25-26, 1998, in Deer Creek. Samples were collected monthly at both sites and more frequently during the spring and early summer months to coincide with application of pesticides. Seventy-eight pesticides and 7 pesticide metabolites were analyzed in 31 samples collected in Deer Creek and in 18 samples collected in South Branch Plum Creek. Of the 85 pesticides and pesticide metabolites analyzed, 25 of the pesticides were detected at least once in Deer Creek, and 20 of the pesticides were detected at least once in South Branch Plum Creek. Atrazine was the most commonly detected pesticide in both streams. There was a distinct seasonal pattern of atrazine, simazine, and metolachlor concentrations measured at both sites.Prometon was detected in 3 of the 18 samples collected in South Branch Plum Creek in 1997 and in 28 of the 31 samples collected in Deer Creek in both 1997 and 1998. Prometon generally is applied in conjunction with asphalt paving projects and is commonly used in residential areas. The highest measured concentrations of prometon detected in Deer Creek were in the five storm samples collected on August 25-26, 1998.At the Deer Creek site, 9 of the 25 pesticides detected throughout the study were detected only in the sample collected on June 13, 1997. Those nine pesticides included acifluorfen, bentazon, bromoxynil, dicamba, dichlorprop, fenuron, linuron, MCPA, and neburon. Nine other pesticides also were detected in that sample.All concentrations of pesticides were well below established drinking-water guidelines. The maximum measured concentration of diazinon in Deer Creek (0.097 µg/L) and South Branch Plum Creek (0.974 µg/L) exceeded the aquatic life guideline of 0.009 µg/L established by the National Academy of Sciences/National Academy of Engineers. The maximum measured concentration of azinphos-methyl in South Branch Plum Creek (an estimated value of 0.033 µg/L) exceeded the chronic aquatic-life guideline of 0.01 µg/L established by the USEPA.Twenty-five samples were collected from Deer Creek and analyzed for volatile organic compounds (VOCs). Of 87 VOCs analyzed for, 22 were detected at least once, and 12 were gasoline-related compounds. Acetone, benzene, carbon disulfide, meta/paraxylene, methyl chloride, MTBE, p-isopropyl toluene, toluene, and 1,2,4-trimethylbenzene were each detected in five or more samples. VOCs generally were detected during the colder winter months and not frequently during the summer months.The maximum measured concentrations of benzene, ethylbenzene, o-dichlorobenzene, styrene, and toluene were two or more orders of magnitude lower than the MCLs established by the USEPA.

Purgeable organic compounds at or near the Idaho Nuclear Technology and Engineering Center, Idaho National Laboratory, Idaho, 2015

USGS Publications Warehouse

Maimer, Neil V.; Bartholomay, Roy C.

2016-05-25

During 2015, the U.S. Geological Survey, in cooperation with the U.S. Department of Energy, collected groundwater samples from 31 wells at or near the Idaho Nuclear Technology and Engineering Center (INTEC) at the Idaho National Laboratory for purgeable organic compounds (POCs). The samples were collected and analyzed for the purpose of evaluating whether purge water from wells located inside an areal polygon established downgradient of the INTEC must be treated as a Resource Conservation and Recovery Act listed waste.POC concentrations in water samples from 29 of 31 wells completed in the eastern Snake River Plain aquifer were greater than their detection limit, determined from detection and quantitation calculation software, for at least one to four POCs. Of the 29 wells with concentrations greater than their detection limits, only 20 had concentrations greater than the laboratory reporting limit as calculated with detection and quantitation calculation software. None of the concentrations exceeded any maximum contaminant levels established for public drinking water supplies. Most commonly detected compounds were 1,1,1-trichoroethane, 1,1-dichloroethene, and trichloroethene.

Hydrologic and water-quality data for U.S. Coast Guard Support Center Kodiak, Alaska, 1987-89

USGS Publications Warehouse

Glass, R.L.

1996-01-01

Hydrologic and water-quality data were collected at the U.S. Coast Guard Support Center Kodiak on Kodiak Island, Alaska, to determine regional ground-water conditions and if contamination of soils, ground water, or surface water has occurred. Eighteen areas of possible contamination were identified. Ground-water levels, surface- water stages, surface-water discharges, and results of field and laboratory analyses of soil and water samples are presented in tabular form. Many quality-assurance samples had detectable concentrations of methylene chloride and 1,2-dichloroethane, which may be due to sampling or laboratory contamination. Concentrations were as great as 5.9 micrograms per liter for methylene chloride and 2.6 micrograms per liter for 1,2-dichloroethane. Excluding 1,2-dichloroethane, most soil, ground-water, and surface-water samples contained no detectable concentrations of the organic constituents that were analyzed. Chemical analyses were performed on two lake-bed-material samples and more than 100 soil samples. The median lead concentration was 9.8 milligrams per kilogram. Concentrations of tetrachloroethene were as great as 1.1 milligram per kilogram in soils near a laundry. Water samples were collected from 101 wells. The maximum benzene concentration detected in ground water was 78 micrograms per liter from a well at the air station near a site where aviation fuel was spilled. Wells near a laundry yielded water having concentrations of tetrachloroethene as great as 3,000 micrograms per liter, and vinyl chloride as great as 440 micrograms per liter. A well in a former aviation gasoline storage area yielded water with a concentration of trichloroethene as great as 66 micrograms per liter. Water samples were collected from 59 sites on streams, lakes, or ponds. Surface-water samples had much lower concen- trations of organic compounds; the highest concentration of benzene was 2.2 micrograms per liter in a stream near a former aviation-fuel storage area and the maximum vinyl chloride concentration was 15 micrograms per liter in a stream near a former landfill. Tetrachloroethene and trichloroethene were not detected in any surface-water samples.

Concentrations of pesticides and pesticide degradates in the Croton River Watershed in southeastern New York, July-September 2000

USGS Publications Warehouse

Phillips, Patrick J.; Bode, Robert W.

2002-01-01

Thirty-seven pesticides and (or) pesticide degradates were detected in baseflow samples collected from 47 stream sites in the Croton River Watershed (374 square miles) in southeastern New York in the summer of 2000. The Croton Reservoir provides about 10 percent of New York City's water supply. Maximum concentrations of most pesticides detected did not exceed 0.1 μg/L (micrograms per liter). This study, by the U.S. Geological Survey in cooperation with the New York State Department of Environmental Conservation, was conducted from July through September 2000 and entailed analysis of the samples for more than 150 pesticides and their degradates. Nine compounds were detected at a concentration greater than 0.10 μg/L; three of these were insecticides (diazinon, carbaryl, and imidacloprid), one was a fungicide (mycobutanil), and five were herbicides (simazine, 2,4-D, diuron, hexazinone, and 2,4-D methyl esther). Only two of these compounds (simazine and 2,4-D) were detected at a concentration exceeding 1 μg/L; the simazine concentration exceeded the New York State surface-water standard of 0.5 μg/L. Two insecticides (diazinon and azinphos-methyl) exceeded aquatic-life-protection standard in one sample each. Concentrations of three insecticides (chlorpyrifos, carbaryl, and malathion) were more than 50 percent of the aquatic-life-protection standards in one sample each.Total concentrations of insecticides and herbicides (the sum of the concentrations, whereby all concentrations below the detection limit were set to zero), and the concentrations of the herbicide prometon and the insecticide diazinon, were highest in samples from watersheds with population densities greater than 510 per square mile (21 sites); therefore, the presence of these compounds is attributable to urban, residential, and other developed land uses.The data obtained in this study are useful for making general comparisons among watersheds with differing land uses, but the concentrations represent baseflow conditions and, thus, are probably lower than the annual maximum concentrations in these streams. A July baseflow sample had total insecticide and fungicide concentrations of less than 0.03 μg/L, whereas a stormflow sample collected at the same site 2 weeks later had a corresponding concentration greater than 0.10 μg/L. Total herbicide concentrations for the July baseflow and stormflow samples were around 0.03 μg/L, but that for a stormflow sample collected at the same site 2 months later was greater than 20 μg/L.

Ground-water quality for Grainger County, Tennessee

USGS Publications Warehouse

Weaver, J.D.; Patel, A.R.; Hickey, A.C.

1994-01-01

The residents of Grainger County depend on ground water for many of their daily needs including personal consumption and crop irrigation. To address concerns associated with ground-water quality related to domestic use, the U.S. Geological Survey collected water samples from 35 wells throughout the county during the summer 1992. The water samples were analyzed to determine if pesticides, nutrients, bacteria, and other selected constituents were present in the ground water. Wells selected for the study were between 100 and 250 feet deep and yielded 10 to 50 gallons of water per minute. Laboratory analyses of the water found no organic pesticides at concentrations exceeding the primary maximum contaminant levels established by the State of Tennessee for wells used for public supply. However, fecal coliform bacteria were detected at concentrations exceeding the State's maximum contaminant level in water from 15 of the 35 wells sampled. Analyses also indicated several inorganic compounds were present in the water samples at concentrations exceeding the secondary maximum contaminant level.

Ground-Water Quality in Western New York, 2006

USGS Publications Warehouse

Eckhardt, David A.V.; Reddy, James E.; Tamulonis, Kathryn L.

2008-01-01

Water samples were collected from 7 production wells and 26 private residential wells in western New York from August through December 2006 and analyzed to characterize the chemical quality of ground water. Wells at 15 of the sites were screened in sand and gravel aquifers, and 18 were finished in bedrock aquifers. The wells were selected to represent areas of greatest ground-water use and to provide a geographical sampling from the 5,340-square-mile study area. Samples were analyzed for 5 physical properties and 219 constituents that included nutrients, major inorganic ions, trace elements, radionuclides, pesticides, volatile organic compounds (VOC), phenolic compounds, organic carbon, and bacteria. Results indicate that ground water used for drinking supply is generally of acceptable quality, although concentrations of some constituents or bacteria exceeded at least one drinking-water standard at 27 of the 33 wells. The cations that were detected in the highest concentrations were calcium, magnesium, and sodium; anions that were detected in the highest concentrations were bicarbonate, chloride, and sulfate. The predominant nutrients were nitrate and ammonia; nitrate concentrations were higher in samples from sand and gravel aquifers than in samples from bedrock. The trace elements barium, boron, copper, lithium, nickel, and strontium were detected in every sample; the trace elements with the highest concentrations were barium, boron, iron, lithium, manganese, and strontium. Eighteen pesticides, including 9 pesticide degradates, were detected in water from 14 of the 33 wells, but none of the concentrations exceeded State or Federal Maximum Contaminant Levels (MCLs). Fourteen volatile organic compounds were detected in water from 12 of the 33 wells, but none of the concentrations exceeded MCLs. Eight chemical analytes and three types of bacteria were detected in concentrations that exceeded Federal and State drinking-water standards, which are typically identical. Sulfate concentrations exceeded the U.S. Environmental Protection Agency (USEPA) Secondary Maximum Contaminant Level (SMCL) of 250 milligrams per liter (mg/L) in three samples, and chloride concentrations exceeded the SMCL of 250 mg/L in two samples. Sodium concentrations exceeded the USEPA Drinking Water Health Advisory of 60 mg/L in nine samples. Iron concentrations exceeded the SMCL of 300 ug/L (micrograms per liter) in 14 filtered samples, and manganese exceeded the USEPA SMCL of 50 ug/L in 15 filtered samples, as well as the New York State MCL of 300 ug/L in 1 filtered sample. Arsenic exceeded the USEPA MCL of 10 ug/L in two samples, aluminum exceeded the SMCL for aluminum of 50 ug/L in one sample, and lead exceeded the MCL of 15 ug/L in one sample. Radon-222 exceeded the proposed USEPA MCL of 300 picocuries per liter in 24 samples. Any detection of coliform bacteria indicates a violation of New York State health regulations; total coliform was detected in 12 samples, and Escherichia coli was detected in 2 samples. The plate counts for heterotrophic bacteria exceeded the MCL (500 colony-forming units per milliliter) in four samples.

Optimizing bulk milk dioxin monitoring based on costs and effectiveness.

PubMed

Lascano-Alcoser, V H; Velthuis, A G J; van der Fels-Klerx, H J; Hoogenboom, L A P; Oude Lansink, A G J M

2013-07-01

Dioxins are environmental pollutants, potentially present in milk products, which have negative consequences for human health and for the firms and farms involved in the dairy chain. Dioxin monitoring in feed and food has been implemented to detect their presence and estimate their levels in food chains. However, the costs and effectiveness of such programs have not been evaluated. In this study, the costs and effectiveness of bulk milk dioxin monitoring in milk trucks were estimated to optimize the sampling and pooling monitoring strategies aimed at detecting at least 1 contaminated dairy farm out of 20,000 at a target dioxin concentration level. Incidents of different proportions, in terms of the number of contaminated farms, and concentrations were simulated. A combined testing strategy, consisting of screening and confirmatory methods, was assumed as well as testing of pooled samples. Two optimization models were built using linear programming. The first model aimed to minimize monitoring costs subject to a minimum required effectiveness of finding an incident, whereas the second model aimed to maximize the effectiveness for a given monitoring budget. Our results show that a high level of effectiveness is possible, but at high costs. Given specific assumptions, monitoring with 95% effectiveness to detect an incident of 1 contaminated farm at a dioxin concentration of 2 pg of toxic equivalents/g of fat [European Commission's (EC) action level] costs €2.6 million per month. At the same level of effectiveness, a 73% cost reduction is possible when aiming to detect an incident where 2 farms are contaminated at a dioxin concentration of 3 pg of toxic equivalents/g of fat (EC maximum level). With a fixed budget of €40,000 per month, the probability of detecting an incident with a single contaminated farm at a dioxin concentration equal to the EC action level is 4.4%. This probability almost doubled (8.0%) when aiming to detect the same incident but with a dioxin concentration equal to the EC maximum level. This study shows that the effectiveness of finding an incident depends not only on the ratio at which, for testing, collected truck samples are mixed into a pooled sample (aiming at detecting certain concentration), but also the number of collected truck samples. In conclusion, the optimal cost-effective monitoring depends on the number of contaminated farms and the concentration aimed at detection. The models and study results offer quantitative support to risk managers of food industries and food safety authorities. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Seasonal and nonseasonal variability of satellite-derived chlorophyll and colored dissolved organic matter concentration in the California Current

NASA Astrophysics Data System (ADS)

Kahru, Mati; Mitchell, B. Greg

2001-02-01

Time series of surface chlorophyll a concentration (Chl) and colored dissolved organic matter (CDOM) derived from the Ocean Color and Temperature Sensor and Sea-Viewing Wide Field-of-View Sensor were evaluated for the California Current area using regional algorithms. Satellite data composited for 8-day periods provide the ability to describe large-scale changes in surface parameters. These changes are difficult to detect based on in situ observations alone that suffer from undersampling the large temporal and spatial variability, especially in Chl. We detected no significant bias in satellite Chl estimates compared with ship-based measurements. The variability in CDOM concentration was significantly smaller than that in Chl, both spatially and temporally. While being subject to large interannual and short-term variations, offshore waters (100-1000 km from the shore) have an annual cycle of Chl and CDOM with a maximum in winter-spring (December-March) and a minimum in late summer. For inshore waters the maximum is more likely in spring (April-May). We detect significant increase in both Chl and CDOM off central and southern California during the La Niña year of 1999. The trend of increasing Chl and CDOM from October 1996 to June 2000 is statistically significant in many areas.

Pharmacokinetics and pharmacodynamics of edivoxetine (LY2216684), a norepinephrine reuptake inhibitor, in pediatric patients with attention-deficit/hyperactivity disorder.

PubMed

Kielbasa, William; Quinlan, Tonya; Jin, Ling; Xu, Wen; Lachno, D Richard; Dean, Robert A; Allen, Albert J

2012-08-01

Edivoxetine (LY2216684) is a selective and potent norepinephrine reuptake inhibitor (NERI). The pharmacokinetics (PK) and pharmacodynamics (PD) of edivoxetine were assessed in children and adolescent patients with attention-deficit/hyperactivity disorder (ADHD) following single and once-daily oral doses of edivoxetine. During a phase 1 open-label safety, tolerability, and PK study, pediatric patients were administered edivoxetine at target doses of 0.05, 0.1, 0.2 and 0.3 mg/kg, and blood samples were collected to determine plasma concentrations of edivoxetine for PK assessments and plasma 3,4-dihydroxyphenylglycol (DHPG) concentrations for PD assessments. Edivoxetine plasma concentrations were measured using liquid chromatography with tandem mass spectrometric detection, and DHPG was measured using liquid chromatography with electrochemical detection. Edivoxetine PK was comparable between children and adolescents. The time to maximum concentration (t(max)) of edivoxetine was ∼2 hours, which was followed by a mono-exponential decline in plasma concentrations with a terminal elimination half-life (t(1/2)) of ∼6 hours. Dose-dependent increases in area under the edivoxetine plasma concentration versus time curve from zero to infinity (AUC(0-∞)) and maximum plasma concentration (C(max)) were observed, and there was no discernable difference in the apparent clearance (CL/F) or the apparent volume of distribution at steady state (V(ss)/F) across the dose range. In adolescents, edivoxetine caused a maximum decrease in plasma DHPG concentrations from baseline of ∼28%, most notably within 8 hours of edivoxetine administration. This initial study in pediatric patients with ADHD provides new information on the PK profile of edivoxetine, and exposures that decrease plasma DHPG consistent with the mechanism of action of a NERI. The PK and PD data inform edivoxetine pharmacology and can be used to develop comprehensive population PK and/or PK-PD models to guide dosing strategies.

Application of health-based screening levels to ground-water quality data in a state-scale pilot effort

USGS Publications Warehouse

Toccalino, Patricia L.; Norman, Julia E.; Phillips, Robyn H.; Kauffman, Leon J.; Stackelberg, Paul E.; Nowell, Lisa H.; Krietzman, Sandra J.; Post, Gloria B.

2004-01-01

A state-scale pilot effort was conducted to evaluate a Health-Based Screening Level (HBSL) approach developed for communicating findings from the U.S. Geological Survey (USGS) National Water-Quality Assessment Program in a human-health context. Many aquifers sampled by USGS are used as drinking-water sources, and water-quality conditions historically have been assessed by comparing measured contaminant concentrations to established drinking-water standards and guidelines. Because drinking-water standards and guidelines do not exist for many analyzed contaminants, HBSL values were developed collaboratively by the USGS, U.S. Environmental Protection Agency (USEPA), New Jersey Department of Environmental Protection, and Oregon Health & Science University, using USEPA toxicity values and USEPA Office of Water methodologies. The main objective of this report is to demonstrate the use of HBSL approach as a tool for communicating water-quality data in a human-health context by conducting a retrospective analysis of ground-water quality data from New Jersey. Another important objective is to provide guidance on the use and interpretation of HBSL values and other human-health benchmarks in the analyses of water-quality data in a human-health context. Ground-water samples collected during 1996-98 from 30 public-supply, 82 domestic, and 108 monitoring wells were analyzed for 97 pesticides and 85 volatile organic compounds (VOCs). The occurrence of individual pesticides and VOCs was evaluated in a human-health context by calculating Benchmark Quotients (BQs), defined as ratios of measured concentrations of regulated compounds (that is, compounds with Federal or state drinking-water standards) to Maximum Contaminant Level (MCL) values and ratios of measured concentrations of unregulated compounds to HBSL values. Contaminants were identified as being of potential human-health concern if maximum detected concentrations were within a factor of 10 of the associated MCL or HBSL (that is, maximum BQ value (BQmax) greater than or equal to 0.1) in any well type (public supply, domestic, monitoring). Most (57 of 77) pesticides and VOCs with human-health benchmarks were detected at concentrations well below these levels (BQmax less than 0.1) for all three well types; however, BQmax values ranged from 0.1 to 3,000 for 6 pesticides and 14 VOCs. Of these 20 contaminants, one pesticide (dieldrin) and three VOCs (1,2-dibromoethane, tetrachloroethylene, and trichloroethylene) both (1) were measured at concentrations that met or exceeded MCL or HBSL values, and (2) were detected in more than 10 percent of samples collected from raw ground water used as sources of drinking water (public-supply and (or) domestic wells) and, therefore, are particularly relevant to human health. The occurrence of multiple pesticides and VOCs in individual wells also was evaluated in a human-health context because at least 53 different contaminants were detected in each of the three well types. To assess the relative human-health importance of the occurrence of multiple contaminants in different wells, the BQ values for all contaminants in a given well were summed. The median ratio of the maximum BQ to the sum of all BQ values for each well ranged from 0.83 to 0.93 for all well types, indicating that the maximum BQ makes up the majority of the sum for most wells. Maximum and summed BQ values were statistically greater for individual public-supply wells than for individual domestic and monitoring wells. The HBSL approach is an effective tool for placing water-quality data in a human-health context. For 79 of the 182 compounds analyzed in this study, no USEPA drinking-water standards or guidelines exist, but new HBSL values were calculated for 39 of these 79 compounds. The new HBSL values increased the number of detected pesticides and VOCs with human-health benchmarks from 65 to 77 (of 97 detected compounds), thereby expanding the basis for interpreting contaminant-occu

Contamination of different portions of raw and boiled specimens of Norway lobster by mercury and selenium.

PubMed

Perugini, Monia; Visciano, Pierina; Manera, Maurizio; Abete, Maria Cesarina; Gavinelli, Stefania; Amorena, Michele

2013-11-01

The aim of this study was to evaluate mercury and selenium distribution in different portions (exoskeleton, white meat and brown meat) of Norway lobster (Nephrops norvegicus). Some samples were also analysed as whole specimens. The same portions were also examined after boiling, in order to observe if this cooking practice could affect mercury and selenium concentrations. The highest mercury concentrations were detected in white meat, exceeding in all cases the maximum levels established by European legislation. The brown meat reported the highest selenium concentrations. In all boiled samples, mercury levels showed a statistically significant increase compared to raw portions. On the contrary, selenium concentrations detected in boiled samples of white meat, brown meat and whole specimen showed a statistically significant decrease compared to the corresponding raw samples. These results indicate that boiling modifies mercury and selenium concentrations. The high mercury levels detected represent a possible risk for consumers, and the publication and diffusion of specific advisories concerning seafood consumption is recommended.

[Exploratory study of air quality in elementary schools, Coimbra, Portugal].

PubMed

Ferreira, Ana Maria Conceiçã; Cardoso, Salvador Massano

2013-12-01

To analyze the air quality in elementary schools and their structural and functional conditions. Air quality in 51 elementary schools (81 classrooms) in the city of Coimbra, Portugal, both inside and outside of the rooms was evaluated during the four seasons, from 2010 to 2011. Temperature (T°), relative humidity (Hr), concentrations of carbon monoxide (CO), carbon dioxide (CO2), ozone (O3), nitrogen dioxide (NO2), sulfur dioxide (SO2), compounds were evaluated, as were volatile organics (VOC), formaldehyde and particulate matter (PM10), from November 2010 to February 2011 (autumn/winter) and March 2011 to June 2011 (spring/summer). A grid characterizing the structural and functional conditions of the schools was created. The statistical Student t test for paired samples and the Wilcoxon t test were applied. In 47 schools, the average CO2 concentrations were above the maximum reference concentration (984 ppm) mentioned in Portuguese legislation. The maximum concentration values found inside the rooms were critical, especially in the fall/winter (5,320 ppm). In some schools the average concentrations of VOC and PM10 within the maximum concentration exceeded the reference legislated. The values (risk) of CO, formaldehyde, NO2, SO2 and O3 detected were not relevant. There was a higher concentration of pollutants inside the rooms compared with outside. Inadequate ventilation is associated with high CO2 concentration in the classroom.

Water-quality conditions at selected landfills in Mecklenburg County, North Carolina, 1986-92

USGS Publications Warehouse

Ferrell, G.M.; Smith, D.G.

1995-01-01

Water-quality conditions at five municipal landfills in Mecklenburg County, North Carolina, were studied during 1986-92. Analytical results of water samples from monitoring wells and streams at and near the landfills were used to evaluate effects of leachate on surface and ground water. Ground-water levels at monitoring wells were used to determine directions of ground-water flow at the landfills. Data from previous studies were used for analysis of temporal trends in selected water-quality properties and chemical constituents. Effects of leachate, such as large biochemical- and chemical-oxygen demands, generally were evident in small streams originating within the landfills, whereas effects of leachate generally were not evident in most of the larger streams. In larger streams, surface-water quality upstream and downstream from most of the landfills was similar. However, the chemical quality of water in Irwin Creek appears to have been affected by the Statesville Road landfill. Concentrations of several constituents indicative of leachate were larger in samples collected from Irwin Creek downstream from the Statesville Road landfill than in samples collected from Irwin Creek upstream from the landfill. The effect of leachate on ground-water quality generally was largest in water from wells adjacent to waste-disposal cells. Concentrations of most constituents considered indicative of leachate generally were smaller with increasing distance from waste-disposal cells. Water samples from offsite wells generally indicated no effect or very small effects of leachate. Action levels designated by the Mecklenburg County Engineering Department and maximum contaminant levels established by the U.S. Environmental Protection Agency were exceeded in some samples from the landfills. Ground-water samples exceeded action levels and maximum contaminant levels more commonly than surface-water samples. Iron and manganese were the constituents that most commonly exceeded action levels in water samples from the landfills. Synthetic organic compounds were detected more commonly and in larger concentrations in ground-water samples than in surface-water samples. Concentrations of synthetic organic compounds detected in water samples from monitoring sites at the landfills generally were much less than maximum contaminant levels. However, concentrations of some chlorinated organic compounds exceeded maximum contaminant levels in samples from several monitoring wells at the Harrisburg Road and York Road landfills. Trend analysis indicated statistically significant temporal changes in concentrations of selected water-quality constituents and properties at some of the monitoring sites. Trends detected for the Holbrooks Road and Statesville Road landfills generally indicated an improvement in water quality and a decrease in effects of leachate at most monitoring sites at these landfills from 1979 to 1992. Water-quality trends detected for monitoring sites at the Harrisburg Road and York Road landfills, the largest landfills in the study, differed in magnitude and direction. Upward trends generally were detected for sites near recently closed waste-disposal cells, whereas downward trends generally were detected for sites near older waste-disposal cells. Temporal trends in water quality generally reflected changes in degradation processes associated with the aging of landfill wastes.

Reconnaissance of arsenic concentrations in ground water from bedrock and unconsolidated aquifers in eight northern-tier counties of Pennsylvania

USGS Publications Warehouse

Low, Dennis J.; Galeone, Daniel G.

2007-01-01

Samples of ground water for analysis of total-arsenic concentrations were collected in eight counties--Potter, Tioga, Bradford, Susquehanna, Wayne, Pike, Sullivan, and Wyoming--and from eight bedrock formations (bedrock aquifers) and overlying glacial aquifers in the north-central and northeastern parts of Pennsylvania in July 2005 and from March through June 2006. The samples were collected from a total of 143 domestic wells, 2 stock wells, 4 non-community wells, 2 community water-system wells, and 3 domestic springs by well or spring owners using sampling kits provided by the U.S. Geological Survey (USGS). An additional 15 domestic wells were sampled by the USGS for analysis of total arsenic. These 15 samples were collected using the same methods and sampling kits provided to the homeowners. Samples were analyzed for total arsenic by the Pennsylvania Department of Environmental Protection Laboratory using a minimum reporting level of 4.0 µg/L (micrograms per liter). Arsenic was detected in water from 18 domestic wells in four counties--Bradford (3 wells), Sullivan (1 well), Tioga (13 wells), and Wayne (1 well). The median concentration of total arsenic was less than 4.0 µg/L, and the maximum concentration was 188 µg/L. Water from 10 wells had concentrations of total arsenic greater than the U.S. Environmental Protection Agency Maximum Contaminant Level of 10 µg/L. Detectable concentrations of total arsenic were measured in water from wells that ranged in depth from 29 to 400 feet, and that were completed in three aquifers--Lock Haven Formation, Catskill Formation, and unconsolidated glacial sediments; no springs had detectable concentrations of total arsenic. Water samples representing the Lock Haven Formation were collected from 60 wells; water from 12 of these wells had detectable concentrations of total arsenic. Water samples representing the Catskill Formation were collected from 57 wells; water from 4 wells had detectable concentrations of total arsenic. Water samples representing the unconsolidated glacial sediments were collected from 17 wells; 2 wells had water with detectable concentrations of total arsenic. Contingency tables tested for significant differences in total arsenic between aquifers, topographic settings, and well depths. Concentrations of total arsenic were significantly greater (95-percent confidence level) in the Lock Haven Formation than in the other bedrock units. Concentrations of total arsenic also varied significantly by topographic setting. Wells completed in the Lock Haven Formation and located in valleys had significantly greater concentrations of total arsenic than similar wells located on hilltops or slopes. Concentrations of total arsenic did not vary significantly by topographic setting in the Catskill Formation. Concentrations of total arsenic did not vary significantly by well depth for any aquifer. Iron staining, hydrogen-sulfide odor, or both were common complaints of well owners. Iron staining was a complaint of 44 well owners. Hydrogen-sulfide odor was a complaint of 35 well owners. Fourteen well owners complained of both iron staining and hydrogen sulfide. No correlation to the presence of arsenic in the wells sampled was found with iron staining, hydrogen-sulfide odor, or both. Water from 8 of the 10 wells that contained concentrations of total arsenic greater than 10 µg/L were sampled by USGS personnel for the determination of concentrations of dissolved arsenic (minimum reporting level 0.3 µg/L) and arsenic species {arsenite [As (III)], arsenate [As (V)], monomethylarsonate (MMA), and dimethylarsinate (DMA)} at the USGS National Water Quality Laboratory. Analytical results from these samples showed a median concentration of 38.7 µg/L dissolved arsenic in water and a maximum of 178 µg/L. As (III) was the most common arsenic species present in the water for seven of the eight wells and was found in water characteristic of reducing environments [pH 8.2 to 9.1, dissolved oxygen 0.06 to 0.29 milligrams per liter (mg/L), and oxidation reduction potential -63 to -203 millivolts (mv)]. As (V) was the dominant arsenic species in water characteristic of an oxidizing environment (pH 4.8, dissolved oxygen 2.15 mg/L, oxidation reduction potential 265 mv). The arsenic species MMA and DMA were detected in the water from two wells. The arsenic species MMA was detected at an estimated concentration of 0.9 µg/L in water from one well; the concentration was less than 1.2 µg/L in water from seven wells. The arsenic species DMA was detected at concentrations of 1.0 and 1.5 µg/L in water from two wells; the concentration was less than 0.6 µg/L in water from six wells. Both wells that contained detectable concentrations of MMA and DMA produced water that was characteristic of reducing environments.

Nutrient, sediment, and pesticide data collected at four small agricultural basins in the Beaver Creek watershed, West Tennessee, 1990-1995

USGS Publications Warehouse

Williams, Shannon D.; Harris, Robin M.

1996-01-01

In 1989, the U.S. Geological Survey began a cooperative study with the Tennessee Department of Agriculture to assess the impact of agricultural activities on water quality in the Beaver Creek watershed in West Tennessee. Quantification of the transport of nutrients, sediment, and pesticides from agricultural fields was one of the objectives of the study. This report presents nutrient, sediment, and pesticide data collected during selected storm events from 1990 through 1995 at four relatively small, agricultural basins (28 to 422 acres) in the Beaver Creek watershed. Approximately 3,000 water samples (500 to 1,000 at each site) were analyzed for nitrogen and phosphorus species. Total nitrogen (N) concentrations ranged from 0.2 to 41.2 milligrams per liter (mg/L). Median concentrations for samples from each site ranged from 2.0 to 2.7 mg/L for total nitrogen, 1.2 to 1.9 mg/L for organic nitrogen, 0.05 to 0.14 mg/L for ammonia (measured as N), and 0.2 to 0.8 mg/L for nitrate plus nitrite (measured as N). Total phosphorus (P) concentrations ranged from 0.03 to 16.0 mg/L. Median concentrations for samples from each site ranged from 0.80 to 1.2 mg/L for total phosphorus and 0.15 to 0.72 for orthophosphate (measured as P). Approximately 6,000 water samples (1,300 to 1,800 at each site) were analyzed for suspended sediment. Suspended-sediment concentrations ranged from 8.0 to 98,353 mg/L. Concentrations exceeded 1,000 mg/L in 33 percent of the samples collected and exceeded 10,000 mg/L in 6 percent of the samples. Median concentrations ranged from 347 to 713 mg/L at the four sites. Several herbicides and insecticides were detected in water samples. Maximum concentrations detected were 37 micrograms per liter for metolachlor, 3.2 for trifluralin, 150 for fluometuron, and 430 for aldicarb. Aldicarb metabolites were also detected in several samples. The maximum aldicarb sulfoxide and aldicarb sulfone concentrations detected were 68.4 and 14.3 micrograms per liter, respectively.

Groundwater-quality data in the North San Francisco Bay Shallow Aquifer study unit, 2012: results from the California GAMA Program

USGS Publications Warehouse

Bennett, George L.; Fram, Miranda S.

2014-01-01

Results for constituents with non-regulatory benchmarks set for aesthetic concerns from the grid wells showed that iron concentrations greater than the CDPH secondary maximum contaminant level (SMCL-CA) of 300 μg/L were detected in 13 grid wells. Chloride was detected at a concentration greater than the SMCL-CA recommended benchmark of 250 mg/L in two grid wells. Sulfate concentrations greater than the SMCL-CA recommended benchmark of 250 mg/L were measured in two grid wells, and the concentration in one of these wells was also greater than the SMCL-CA upper benchmark of 500 mg/L. TDS concentrations greater than the SMCL-CA recommended benchmark of 500 mg/L were measured in 15 grid wells, and concentrations in 4 of these wells were also greater than the SMCL-CA upper benchmark of 1,000 mg/L.

Pesticide Residues in Honey from the Major Honey Producing Forest Belts in Ghana.

PubMed

Darko, Godfred; Addai Tabi, Jonah; Adjaloo, Michael Kodwo; Borquaye, Lawrence Sheringham

2017-01-01

Concentrations of pesticides residues in honey sampled from the major honey producing forest belts in Ghana were determined. Samples were purposively collected and extracted using the QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) method and analysed for synthetic pyrethroids, organochlorine, and organophosphate pesticide residues. Aldrin, γ -HCH, β -HCH, ∑endosulfan, cyfluthrin, cypermethrin, deltamethrin, permethrin methoxychlor, ∑DDT, chlorpyrifos, fenvalerate, malathion, dimethoate, and diazinon were all detected at the concentration of 0.01 mg/kg, while cyfluthrin and permethrin were detected at mean concentrations of 0.02 and 0.04 mg/kg, respectively. All the pesticide residues detected were very low and below their respective maximum residue limits set by the European Union. Hence, pesticide residues in honey samples analyzed do not pose any health risk to consumers.

Glyphosate and AMPA, "pseudo-persistent" pollutants under real-world agricultural management practices in the Mesopotamic Pampas agroecosystem, Argentina.

PubMed

Primost, Jezabel E; Marino, Damián J G; Aparicio, Virginia C; Costa, José Luis; Carriquiriborde, Pedro

2017-10-01

In the Pampas, public concern has strongly risen because of the intensive use of glyphosate for weed control and fallow associated with biotech crops. The present study was aimed to evaluate the occurrence and concentration of the herbicide and its main metabolite (AMPA) in soil and other environmental compartments of the mentioned agroecosystem, including groundwater, in relation to real-world agricultural management practices in the region. Occurrence was almost ubiquitous in solid matrices (83-100%) with maximum concentrations among the higher reported in the world (soil: 8105 and 38939; sediment: 3294 and 7219; suspended particulate matter (SPM): 584 and 475 μg/kg of glyphosate and AMPA). Lower detection frequency was observed in surface water (27-55%) with maximum concentrations in whole water of 1.80 and 1.90 μg/L of glyphosate and AMPA, indicating that SPM analysis would be more sensitive for detection in the aquatic ecosystem. No detectable concentrations of glyphosate or AMPA were observed in groundwater. Glyphosate soil concentrations were better correlated with the total cumulative dose and total number of applications than the last spraying event dose, and an increment of 1 mg glyphosate/kg soil every 5 spraying events was estimated. Findings allow to infer that, under current practices, application rates are higher than dissipation rates. Hence, glyphosate and AMPA should be considered "pseudo-persistent" pollutants and a revisions of management procedures, monitoring programs, and ecological risk for soil and sediments should be also recommended. Copyright © 2017 Elsevier Ltd. All rights reserved.

Water quality of surficial aquifers in the Georgia-Florida Coastal Plain

USGS Publications Warehouse

Crandall, C.A.; Berndt, M.P.

1996-01-01

The National Water Quality Assessment Program of the U.S. Geological Survey established the Georgia-Florida Coastal Plain study unit in 1991. The ground-water study-unit survey was conducted in 1993 to provide a broad over-view of water quality in surficial aquifers. Three land resource provinces were included in the Georgia-Florida Coastal Plain study-unit survey: the Central Florida Ridge, the Coastal Flatwoods, and the Southern Coastal Plain. The U.S. Geological Survey sampled 37 wells in surficial aquifers, 18 in the Coastal Flatwoods and 19 in the Southern Coastal Plain. The Florida Department of Environmental Protection sampled 27 wells tapping surficial aquifers in the Central Florida Ridge as part of the background ground-water quality monitoring network from 1985 through 1989. The data were used to characterize water quality in surficial aquifers of the Central Florida Ridge. Results of the study-unit survey indicated that dissolved solids concentrations in ground water were mostly less than 100 mg/L (milligrams per liter). Higher medians of pH, specific conductance, and concentrations of calcium, bicarbonate, and dissolved solids were measured in samples from the Central Florida Ridge compared to the Southern Coastal Plain and Coastal Flatwoods, probably because of a greater percentage of carbonate minerals in aquifer materials. The U.S. Environmental Protection Agency secondary maximum contaminant level for iron of 300 ug/L (micrograms per liter) in drinking water was exceeded in 15 of 45 samples. Concentrations of nitrate as nitrogen were less than 3.0 mg/L in most samples (74 percent), indicating little or no influence from human activity. Only five samples (9 percent) had concentrations above 10 mg/L, the U.S. Environmental Protection Agency maximum contaminant level for nitrate concentration in drinking water. Significantly lower median concentrations of nitrate were measured in samples from polyvinyl chloride monitoring wells with diameters less than 6 inches than in large diameter, uncased, or iron-cased wells. The median nitrate concentration was 0.05 mg/L in water from monitoring wells, 1.0 mg/L in samples from iron cased wells, and 2.0 mg/L in samples from uncased wells. Concentrations of volatile organic compounds were mostly less than the detection levels and exceeded 1 ug/L in only four samples. Compounds detected at concentrations greater than 1 ug/L were: tetrachloroethane (8.77 ug/L), toluene (23 ug/L) and chloromethane (21 ug/L). Atrazine, desethyl-atrazine, and metolachlor were the only pesticides detected; concentrations were less than 0.02 ug/L, except for metolachlor (2.5 ug/L). Detection of organic compounds in surficial aquifer may be associated with specific activities or sources near the well. Concentrations of radon exceeded the U.S. Environmental Protection Agency proposed maximum contaminant level of 300 picocuries per liter (pCi/L) in 33 samples from wells on the Coastal Flatwoods and the Southern Coastal Plain. Concentrations as high as 13,000 pCi/L were detected in northern Florida. Although uranium concentrations were less than 1 ug/L in all but one sample (1.3 ug/L) from the Southern Coastal Plain, elevated radon concentrations indicate that uranium is present in aquifer material. Uranium is most likely sorbed to iron oxides and clays in subsurface materials. Tritium concentrations indicated that ground water was recharged by precipitation during the past 40 years. Higher concentrations of tritium in ground water were found in the northern part of the study area and may be related to Savannah River Nuclear Facility.

Total lead concentration in new decorative enamel paints in Lebanon, Paraguay and Russia.

PubMed

Clark, C Scott; Speranskaya, Olga; Brosche, Sara; Gonzalez, Hebe; Solis, Daniela; Kodeih, Naji; Roda, Sandy; Lind, Caroline

2015-04-01

Lead concentrations in new enamel decorative paints were determined in three countries in different areas of the world where data were not previously available. The average total lead concentration of the enamel decorative paints purchased in Lebanon, Paraguay and Russia was 24,500ppm (ppm, dry weight), more than 270 times the current limit of 90ppm in Canada and in the United States. Sixty-three percent of these paints contained concentrations greater than 90ppm. Fifty-nine percent contained concentrations greater than 600ppm, the current limit in some countries. The maximum concentrations found were 236,000ppm in Lebanon, 169,000ppm in Paraguay and 52,900ppm in Russia. An average of 29% of the samples contained exceedingly high lead concentrations, >=10,000ppm. Five brands of paint were sampled in each of Lebanon and Paraguay and seven in Russia. Three colors from each brand were analyzed. For five of the six samples of the two brands in Lebanon with affiliations outside the country, the lead concentrations ranged from 1360ppm to 135,000ppm. In Lebanon the maximum concentration in the Egypt-affiliated brand (Sipes) was 135,000ppm and the maximum for the USA-affiliated brand (Dutch Boy) was 32,400ppm. Lead was not detected in any paints from the three of the four brands of paint purchased in Paraguay that had headquarters/affiliations in other countries (Brazil-Coralit), Germany (Suvinil) and USA (Novacor)). Two of the three paints from each of the other Paraguay brands contained high levels of lead with the maximum concentrations of 108,000 and 168,000ppm; one of these brands was manufactured under a license from ICI in the Netherlands. All of the paints purchased in Russia were from Russian brands and were manufactured in Russia. All three paints from one brand contained below detection levels of lead. The maximum levels of lead in the other six brands in Russia ranged from 3230 to 52,900ppm. The two brands with the highest lead concentration, TEKS and LAKRA, were produced by companies in the top three in market share.. Overall, lead concentrations were much higher in the colored paints such as red and yellow than in white paints. In each of the three countries a brand based in that country had a colored paint that either met a 90ppm limit or was close to meeting the limit-demonstrating that practical technology was available in each of these countries to produce low lead bright colored enamel decorative paints. Even though technology for producing paint without added lead existed in each of these countries, twenty-nine (29) percent of the paints analyzed contained exceedingly high concentrations (>=10,000ppm) of lead. Copyright © 2015 Elsevier Inc. All rights reserved.

Effects of agriculture on quality of water in surficial sand-plain aquifers in Douglas, Kandiyohi, Pope, and Stearns counties, Minnesota

USGS Publications Warehouse

Anderson, H.W.

1989-01-01

Four of eight wells sampled for herbicides in west-central Minnesota had detectable concentrations of the triazine herbicide atrazine that ranged from 0.2 to 0.6 micrograms per liter. These concentrations were well below the water-quality guidelines published by the Canadian Inland Waters Directorate, Water Quality Branch, which specify 100 micrograms per liter as the maximum permissible concentration for the group of triazine herbicides in a raw drinking-water supply.

Nutrients and pesticides in ground water of the Ozark Plateaus in Arkansas, Kansas, Missouri, and Oklahoma

USGS Publications Warehouse

Adamski, James C.

1997-01-01

A total of 229 ground-water samples were collected from 215 sites as part of the Ozark Plateaus study unit of the National Water-Quality Assessment Program. These samples were collected from 1993 through 1995 using a network of springs and wells with three scale-dependent components. The first component, the study-unit survey, consisted of 99 randomly selected springs and domestic wells in the Springfield Plateau and Ozark aquifers. The second component, two land-use studies, consisted of 42 springs and domestic wells in a poultry-dominated agricultural area and 40 springs and domestic wells in a cattle-dominated agricultural area overlying the Springfield Plateau aquifer. The third component, the small-watershed study, consisted of 4 springs, 18 domestic wells, and 11 monitoring wells in a small basin within the poultry land-use study area. Samples were analyzed for major ions, nutrients, dissolved organic carbon, methylene blue active substances, tritium, and 88 pesticides and metabolites.The water-quality data from these samples were analyzed with descriptive and statistical methods. Nitrite plus nitrate, which was detected more often and in greater concentrations than any of the other nutrients, ranged from less than 0.05 to 25 milligrams per liter as nitrogen. Nitrite plus nitrate concentrations positively correlated to percent agricultural land use around each site. Median nitrite plus nitrate concentrations generally were greater in samples from springs than in samples from wells. Concentrations of nitrite, ammonia, and ammonia plus organic nitrogen were also affected by land use and also by concentrations of dissolved oxygen in the ground water. Concentrations of phosphorus and orthophosphate probably were affected by land use and also by phosphorus solubility. Pesticides were detected in 80 of 229 samples from 73 of 215 sites. A total of 20 pesticides were detected with a maximum of 5 pesticides detected in any 1 sample. The most commonly detected pesticides were tebuthiuron, atrazine, prometon, desethylatrazine, and simazine. Maximum concentrations ranged from 0.003 to 1.0 microgram per liter. The occurrence and distribution of pesticides were related to land use. Percent agricultural land use was greater for samples with pesticides detected than for samples with no pesticides detected. Pesticides were detected more often in samples from springs than in samples from wells. The occurrence of pesticides also was related to seasonality and chemical characteristics, such as solubility and persistence, of the compounds.

Regional assessment of concentrations and sources of pharmaceutically active compounds, pesticides, nitrate, and E. coli in post-glacial aquifer environments (Canada).

PubMed

Saby, Marion; Larocque, Marie; Pinti, Daniele L; Barbecot, Florent; Gagné, Sylvain; Barnetche, Diogo; Cabana, Hubert

2017-02-01

There is growing concern worldwide about the exposure of groundwater resources to pharmaceutically active compounds (PhACs) and agricultural contaminants, such as pesticides, nitrate, and Escherichia coli. For regions with a low population density and an abundance of water, regional contamination assessments are not carried out systematically due to the typically low concentrations and high costs of analyses. The objectives of this study were to evaluate regional-scale contaminant distributions in untreated groundwater in a rural region of Quebec (Canada). The geological and hydrogeological settings of this region are typical of post-glacial regions around the world, where groundwater flow can be complex due to heterogeneous geological conditions. A new spatially distributed Anthropogenic Footprint Index (AFI), based on land use data, was developed to assess surface pollution risks. The Hydrogeochemical Vulnerability Index (HVI) was computed to estimate aquifer vulnerability. Nine wells had detectable concentrations of one to four of the 13 tested PhACs, with a maximum concentration of 116ng·L -1 for benzafibrate. A total of 34 of the 47 tested pesticides were detected in concentrations equal to or greater than the detection limit, with a maximum total pesticide concentration of 692ng·L -1 . Nitrate concentrations exceeded 1mg·L -1 N-NO 3 in 15.3% of the wells, and the Canadian drinking water standard was exceeded in one well. Overall, 13.5% of the samples had detectable E. coli. Including regional-scale sources of pollutants to the assessment of aquifer vulnerability with the AFI did not lead to the identification of contaminated wells, due to the short groundwater flow paths between recharge and the sampled wells. Given the occurrence of contaminants, the public health concerns stemming from these new data on regional-scale PhAC and pesticide concentrations, and the local flow conditions observed in post-glacial terrains, there is a clear need to investigate the sources and behaviours of local-scale pollutants. Copyright © 2016 Elsevier B.V. All rights reserved.

Nitrate and pesticides in ground water in the eastern San Joaquin Valley, California : occurrence and trends

USGS Publications Warehouse

Burow, Karen R.; Stork, Sylvia V.; Dubrovsky, N.M.

1998-01-01

The occurrence of nitrate and pesticides in ground water in California's eastern San Joaquin Valley may be greatly influenced by the long history of intensive farming and irrigation and the generally permeable sediments. This study, which is part of the U.S. Geological Survey National Water-Quality Assessment Program, was done to assess the quality of the ground water and to do a preliminary evaluation of the temporal trends in nitrate and pesticides in the alluvial fans of the eastern San Joaquin Valley. Ground-water samples were collected from 30 domestic wells in 1995 (each well was sampled once during 1995). The results of the analyses of these samples were related to various physical and chemical factors in an attempt to understand the processes that control the occurrence and the concentrations of nitrate and pesticides. A preliminary evaluation of the temporal trends in the occurrence and the concentration of nitrate and pesticides was done by comparing the results of the analyses of the 1995 ground-water samples with the results of the analyses of the samples collected in 1986-87 as part of the U.S. Geological Survey Regional Aquifer-System Analysis Program. Nitrate concentrations (dissolved nitrate plus nitrite, as nitrogen) in ground water sampled in 1995 ranged from less than 0.05 to 34 milligrams per liter, with a median concentration of 4.6 milligrams per liter. Nitrate concentrations exceeded the maximum contaminant level of 10 milligrams per liter (as nitrogen) in 5 of the 30 ground-water samples (17 percent), whereas 12 of the 30 samples (40 percent) had nitrate concentrations less than 3.0 milligrams per liter. The high nitrate concentrations were associated with recently recharged, well-oxygenated ground water that has been affected by agriculture (indicated by the positive correlations between nitrate, dissolved-oxygen, tritium, and specific conductance). Twelve pesticides were detected in 21 of the 30 ground-water samples (70 percent) in 1995, although only 5 pesticides were detected in more than 10 percent of the ground-water samples. All 12 pesticides were detected at concentrations below the maximum contaminant levels, except the banned soil fumigants 1,2-dibromo-3-chloropropane (3 detections) and 1,2-dibromoethane (1 detection). Atrazine and desethyl atrazine (a transformation product of atrazine) were the most frequently detected pesticides; they were detected in 11 ground-water samples. The frequent detections of atrazine and desethyl atrazine may be related either to past applications of atrazine or to recent application on rights-of-way. Simazine was detected in 10 ground-water samples and diuron was detected in 4 ground-water samples. The detections of simazine and diuron are generally consistent with their reported applications on the crops near the wells where they were detected. 1,2,3-trichloropropane, a manufacturing by-product of 1,2-dichloropropane and 1,3- dichloropropene formulations, was detected in 4 ground-water samples. The occurrence of 1,2,3-trichloropropane, 1,2-dibromo-3-chloropropane, and 1,2-dibromoethane is probably related to past use. Similar to nitrate concentrations, pesticide occurrence was positively correlated to dissolved-oxygen concentrations, indicating that areas with high dissolved-oxygen concentrations may be vulnerable to contamination by nitrate and pesticides. High dissolved-oxygen concentrations may be associated with water that has been rapidly recharged. A comparison of the concentrations and the occurrence of nitrate and pesticides between 1986-87 and 1995 indicates that nitrate concentrations may pose a greater threat to the quality of the ground-water resource in this region than pesticides, in the context of current drinking-water standards. Nitrate concentrations were significantly higher in the 1995 ground-water samples than in the 1986-87 samples collected from the same wells. Although the number of pesticide detections in 1995 is higher than the numb

Relation of pesticide concentrations to season, streamflow, and land use in seven New Jersey streams

USGS Publications Warehouse

Reiser, Robert G.

1999-01-01

The presence and variability of pesticides in seven New Jersey streams was documented by analyzing 146 samples collected from the streams from April 1996 through June 1998. The samples were analyzed for 85 pesticides, including 50 herbicides, 28 insecticides, and 7 degradation products, at method detection limits that ranged from 0.001 to 0.018 μg/L (micrograms per liter). Pesticides were frequently detected; however, concentrations were generally low. The pesticides most frequently detected were atrazine, in 97 percent of the samples; prometon, 96 percent; metolachlor, 95 percent; desethyl-atrazine, 91 percent; simazine, 88 percent; diazinon, 58 percent; alachlor, 56 percent; and carbaryl, 54 percent. Detection frequencies were highest during the growing season (April-September). At least one pesticide was detected in all but one of these samples, and 49 percent of the samples contained 9 or more pesticides. The numbers of pesticides detected at a given site ranged from 13 to 29. Ten pesticides were detected at concentrations that exceeded established water-quality criteria. Thirty-one of these detections were in samples collected during the growing season and one during the nongrowing season. The pesticides that exceeded the U.S. Environmental Protection Agency (USEPA) maximum contaminant level for drinking water were atrazine, which exceeded 3 μg/L in four samples, and alachlor, 2 μg/L in two samples. Cyanazine exceeded the USEPA liftime health advisory level (HAL) of 1 μg/L in two samples. These eight detections occurred during runoff shortly after spring pesticide applications and represent a potential threat to municipal water supplies in the Raritan River basin. Concentrations of chlorpyrifos, chlorthalonil, diazinon, ethyl-parathion, and methyl-azinphos exceeded the chronic life criteria for the protection of aquatic life (ACQR) in 20 samples at four sites during the growing season. Dieldrin was detected in four samples and DDE in two samples at concentrations that exceeded New Jersey Department of Environmental Protection (NJDEP) human health criteria. Individual and total-pesticide concentrations and total numbers of pesticides detected in the samples varied with season and flow conditions. Median and maximum concentrations of most of the pesticides were highest during runoff in the growing season. Pesticide concentrations were typically lower and less variable in the nongrowing season than in the growing season, regardless of changes in hydrologic conditions; however, median concentrations of most pesticides were slightly lower during runoff than during base flow. The median total-pesticide concentration and median total number of pesticides detected were highest and most variable in runoff samples in the growing season. In the nongrowing season, the median total-pesticide concentration was lowest in runoff samples and least variable during base-flow conditions. Median total numbers of pesticides were lowest and least varibale in the nongrowing season during base-flow conditions at most sites. The highest total-pesticide concentrations were detected in samples from the two small agricultural basins (greater than 25 percent of land use is agricultural) during runoff in late spring and early summer. In general, insecticides were detected more frequently and in greater concentrations at urban sites. Concentrations of agricultural herbicides generally decreased with increasing flow at the four sites with less than 10 percent agriculture land use and increased with increasing flow at the three sites with more than 25 percent agricultural land use. Most of the pesticides that correlated positively with streamflow were detected at sites where land use in the basin would indicate the use of those particular pesticides. Most of the pesticides that correlated negatively with streamflow were present at the site in the Coastal Plain or at sites in which the land use in the basin would not indicate heavy u

Determination of concentration factors for Cs-137 and Ra-226 in the mullet species Chelon labrosus (Mugilidae) from the South Adriatic Sea.

PubMed

Antovic, Ivanka; Antovic, Nevenka M

2011-07-01

Concentration factors for Cs-137 and Ra-226 transfer from seawater, and dried sediment or mud with detritus, have been determined for whole, fresh weight, Chelon labrosus individuals and selected organs. Cesium was detected in 5 of 22 fish individuals, and its activity ranged from 1.0 to 1.6 Bq kg(-1). Radium was detected in all fish, and ranged from 0.4 to 2.1 Bq kg(-1), with an arithmetic mean of 1.0 Bq kg(-1). In regards to fish organs, cesium activity concentration was highest in muscles (maximum - 3.7 Bq kg(-1)), while radium was highest in skeletons (maximum - 25 Bq kg(-1)). Among cesium concentration factors, those for muscles were the highest (from seawater - an average of 47, from sediment - an average of 3.3, from mud with detritus - an average of 0.8). Radium concentration factors were the highest for skeleton (from seawater - an average of 130, from sediment - an average of 1.8, from mud with detritus - an average of 1.5). Additionally, annual intake of cesium and radium by human adults consuming muscles of this fish species has been estimated to provide, in aggregate, an effective dose of about 4.1 μSv y(-1). 2011 Elsevier Ltd. All rights reserved.

Illicit drugs and pharmaceuticals in swimming pool waters.

PubMed

Fantuzzi, G; Aggazzotti, G; Righi, E; Predieri, G; Castiglioni, S; Riva, F; Zuccato, E

2018-09-01

The occurrence of illicit drugs (cocaine, opioids, amphetamines and cannabis derivatives), some of their metabolites and 48 pharmaceuticals, was investigated in pool and source waters in ten Italian indoor swimming pools. The samples were analyzed by highperformance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), after solid phase extraction (SPE). Cocaine and its metabolites were found in nine swimming pools, at concentrations from 0.3 to 4.2 ng/L for cocaine, 1.1 to 48.7 ng/L for norcocaine, 0.7 to 21.4 ng/L for benzoylecgonine and 0.1 to 7.3 ng/L for norbenzoylecgonine. Opioids, amphetamines and cannabis derivatives were never detected. The most frequent pharmaceuticals were anti-inflammatory drugs: ibuprofen was found in all the pool waters, with a maximum 197 ng/L and ketoprofen was detected in 9/10 samples (maximum 127 ng/L). Among anticonvulsants, carbamazepine and its metabolite, 10,11-dihydro-10,11dihydroxycarbamazepine, were frequent in swimming pool water (8/10 samples) at concentrations up to 62 ng/L. The cardiovascular drug valsartan was also found frequently (8/10 samples), but at lower concentrations (up to 9 ng/L). Other pharmaceuticals were detected occasionally and at lower concentrations (atenolol, enalapril, paracetamol, hydroclorothiazide, irbesartan and dehydro-erythromycin). Carbamazepine, irbesartan and dehydroerythromycin were detected at very low levels (up to 5 ng/L) in only one of the four source water samples. A quantitative risk assessment showed that the health risk for humans to these substance in swimming pool waters was generally negligible, even for vulnerable subpopulations such as children and adolescents. Copyright © 2018 Elsevier B.V. All rights reserved.

Quality of water on the Prairie Band Potawatomi Reservation, northeastern Kansas, February 1999 through February 2001

USGS Publications Warehouse

Trombley, T.J.

2001-01-01

Water-quality samples were collected from 20 surface-water sites and 7 ground-water sites across the Prairie Band Potawatomi Reservation in northeastern Kansas as part of a water-quality study begun in 1996. Water quality is a very important consideration for the tribe. Three creeks draining the reservation, Soldier, Little Soldier, and South Cedar Creeks, are important tribal resources used for maintaining subsistence fishing and hunting needs for tribal members. Samples were collected twice during June 1999 and June 2000 at all 20 surface-water sites after herbicide application, and nine quarterly samples were collected at 5 of the 20 sampling sites from February 1999 through February 2001. Samples were collected once at six wells and twice at one well from September through December 2000. Surface-water-quality constituents analyzed included nutrients, pesticides, and bacteria. In addition to nutrients, pesticides, and bacteria, ground-water constituents analyzed included major dissolved ions, arsenic, boron, and dissolved iron and manganese. The median nitrite plus nitrate concentration was 0.376 mg/L (milligram per liter) for 81 surface-water samples, and the maximum concentration was 4.18 mg/L as nitrogen, which is less than one-half the U.S. Environmental Protection Agency's Maximum Contaminant Level (MCL) for drinking water of 10 mg/L as nitrogen. Fifty-one of the 81 surface-water-quality samples exceeded the U.S. Environmental Protection Agency's recommended goal for total phosphorus of 0.10 mg/L for the protection of aquatic life. Triazine concentrations in 26 surface-water-quality samples collected during May and June 1999 and 2000 exceeded 3.0 ?g/L (micrograms per liter), the Maximum Contaminant Level established for drinking water by the U.S. Environmental Protection Agency. Triazine herbicide concentrations tended to be highest during late spring runoff after herbicide application. High concentrations of fecal indicator bacteria in surface water are a concern on the reservation with fecal coliform concentrations ranging from 4 to greater than 31,000 colonies per 100 milliliters of water with a median concentration of 570 colonies per 100 milliliters. More than one-half of the surface-water-quality samples exceeded the Kansas Department of Health and Environment contact recreation criteria of 200 and 2,000 colonies per 100 milliliters of water and were collected mostly during the spring and summer. Two wells had sodium concentrations of about 10 times the U.S. Environmental Protection Agengy health advisory level (HAL) of 20 mg/L; concentrations ranged from 241 to 336 mg/L. In water from two wells, sulfate concentrations exceeded 800 mg/L, more than three times the U.S. Environmental Protection Agency Secondary Maximum Contaminant Level (SMCL) for drinking water of 250 mg/L. All but two of the eight ground-water-quality samples had dissolved-solids concentrations exceeding the SMCL of 500 mg/L. The highest concentration of 2,010 mg/L was more than four times the SMCL. Dissolved boron concentrations exceeded the U.S. Environmental Protection Agency 600-?g/L HAL in water from two of the seven wells sampled. Because the HAL is for a lifetime of exposure, the anticipated health risk due to dissolved boron is low. Dissolved iron concentrations in ground-water samples exceeded the 300-?g/L SMCL for treated drinking water in three of the seven wells sampled. Dissolved manganese concentrations in water from the same three wells also exceeded the established SMCL of 50 ?g/L. Dissolved pesticides were not detected in any of the well samples; however, there were degradation products of the herbicides alachlor and metolachlor in several samples. Insecticides were not detected in any ground-water-quality samples. Low concentrations of E. coli and fecal coliform bacteria were detected in water from two wells, and E. coli was detected in water from one well. Much higher concentrations of E. coli, fecal coliform, and fecal strepto

Metals and pesticides in commercial bivalve mollusc production areas in the North and South Bays, Santa Catarina (Brazil).

PubMed

de Souza, R V; Garbossa, L H P; Campos, C J A; Vianna, L F de N; Vanz, A; Rupp, G S

2016-04-15

Concentrations of heavy metals were quantified in mussels Perna perna and Pacific oysters Crassostrea gigas in 28 cultivation sites in the North and South Bays, SC (Brazil). Concentrations of pesticides were also quantified in these bivalve, water and sediment samples collected in 14 cultivation sites on four occasions in the period October 2012-October 2013. Pesticides were not detected in any of the mussel, oyster, water or sediment samples. The South Bay was found to be generally more contaminated with As while the North Bay showed higher concentrations of Ni. Concentrations of Pb and Cd were below the limit of detection of the method (0.5mg/kg) in all samples. Mussels accumulated more As and Ni than oysters, while the opposite was observed for Cu. Metal concentrations were below the maximum levels for foodstuffs specified in the Brazilian legislation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Herbicide contamination and the potential impact to seagrass meadows in Hervey Bay, Queensland, Australia.

PubMed

McMahon, Kathryn; Bengtson Nash, Susan; Eaglesham, Geoff; Müller, Jochen F; Duke, Norman C; Winderlich, Steve

2005-01-01

Low concentrations of herbicides (up to 70 ng l(-1)), chiefly diuron (up to 50 ng l(-1)) were detected in surface waters associated with inter-tidal seagrass meadows of Zostera muelleri in Hervey Bay, south-east Queensland, Australia. Diuron and atrazine (up to 1.1 ng g(-1) dry weight of sediment) were detected in the sediments of these seagrass meadows. Concentration of the herbicides diuron, simazine and atrazine increased in surface waters associated with seagrass meadows during moderate river flow events indicating herbicides were washed from the catchment to the marine environment. Maximum herbicide concentration (sum of eight herbicides) in the Mary River during a moderate river flow event was 4260 ng l(-1). No photosynthetic stress was detected in seagrass in this study during low river flow. However, with moderate river flow events, nearshore seagrasses are at risk of being exposed to concentrations of herbicides that are known to inhibit photosynthesis.

Interferometric nanoimmunosensor for label-free and real-time monitoring of Irgarol 1051 in seawater.

PubMed

Chocarro-Ruiz, Blanca; Herranz, Sonia; Fernández Gavela, Adrián; Sanchís, Josep; Farré, Marinella; Marco, M Pilar; Lechuga, Laura M

2018-05-26

An interferometric nanobiosensor for the specific and label-free detection of the pollutant Irgarol 1051 directly in seawater has been settled. Due to the low molecular weight of Irgarol pollutant and its expected low concentration in seawater, the sensor is based on a competitive inhibition immunoassay. Parameters as surface biofunctionalization, concentration of the selective antibody and regeneration conditions have been carefully evaluated. The optimized immunosensor shows a limit of detection of only 3 ng/L, well below the 16 ng/L set by the EU as the maximum allowable concentration in seawater. It can properly operate during 30 assay-regeneration cycles using the same sensor biosurface and with a time-to-result of only 20 min for each cycle. Moreover, the interferometric nanosensor is able to directly detect low concentrations of Irgarol 1051 in seawater without requiring sample pre-treatments and without showing any background signal due to sea matrix effect. Copyright © 2018 Elsevier B.V. All rights reserved.

An environmental forensic procedure to analyse anthropogenic pressures of urban origin on surface water of protected coastal agro-environmental wetlands (L'Albufera de Valencia Natural Park, Spain).

PubMed

Pascual-Aguilar, Juan; Andreu, Vicente; Picó, Yolanda

2013-12-15

Detection and spatial distribution of 14 drugs of abuse and 17 pharmaceuticals in surface waters was investigated to determine transport hydrological connectivity between urban, agriculture and natural environments. Solid-phase extraction and liquid chromatography tandem mass spectrometry was applied to all samples. To determine spatial incidence of contaminants, analytical results of target compounds were georeferenced and integrated into a geographical information systems structure together with layers of municipal population, location of sewage water treatment plants and irrigation channels and sectors. The methodology was applied to L'Albufera Natural Park in Valencia (Spain). A total of 9 drugs of abuse were detected at 16 points (76% of the sample sites). Cocaine and its metabolite, benzoylecgonine, were the most detected substances, being found in 12 and 16 samples, respectively. Maximum concentrations were found in benzoylecgonine (78.71 ng/L) and codeine (51.60 ng/L). Thirteen pharmaceuticals were found at 16 points. The most detected compounds were carbamazepine (15 samples) and ibuprofen (11 samples). Maximum concentrations were detected in acetaminophen (17,699.4 ng/L), ibuprofen (3913.7 ng/L) and codeine (434.0 ng/L). Spatial distribution of pharmaceuticals showed a clear relationship between irrigation areas, high population densities municipalities (above 1000 h/km(2)) and sewage water treatment plants. Copyright © 2013 Elsevier B.V. All rights reserved.

Methods for the preparation and analysis of solids and suspended solids for methylmercury

USGS Publications Warehouse

DeWild, John F.; Olund, Shane D.; Olson, Mark L.; Tate, Michael T.

2004-01-01

This report presents the methods and method performance data for the determination of methylmercury concentrations in solids and suspended solids. Using the methods outlined here, the U.S. Geological Survey's Wisconsin District Mercury Laboratory can consistently detect methylmercury in solids and suspended solids at environmentally relevant concentrations. Solids can be analyzed wet or freeze dried with a minimum detection limit of 0.08 ng/g (as-processed). Suspended solids must first be isolated from aqueous matrices by filtration. The minimum detection limit for suspended solids is 0.01 ng per filter resulting in a minimum reporting limit ranging from 0.2 ng/L for a 0.05 L filtered volume to 0.01 ng/L for a 1.0 L filtered volume. Maximum concentrations for both matrices can be extended to cover nearly any amount of methylmercury by limiting sample size.

Six orders of magnitude dynamic range in capillary electrophoresis with ultrasensitive laser-induced fluorescence detection

PubMed Central

Whitmore, Colin D.; Essaka, David; Dovichi, Norman J.

2009-01-01

An ultrasensitive laser-induced fluorescence detector was used with capillary electrophoresis for the study of 5-carboxy-tetramethylrhodamine. The raw signal from the detector provided roughly three orders of magnitude dynamic range. The signal saturated at high analyte concentrations due to the dead time associated with the single-photon counting avalanche photodiode employed in the detector. The signal can be corrected for the detector dead time, providing an additional order of magnitude dynamic range. To further increase dynamic range, two fiber-optic beam-splitters were cascaded to generate a primary signal and two attenuated signals, each monitored by a single-photon counting avalanche photodiode. The combined signals from the three photodiodes are reasonably linear from the concentration detection limit of 3 pM to 10 μM, the maximum concentration investigated, a range of 3,000,000. Mass detection limits were 150 yoctomoles injected onto the capillary. PMID:19836546

Spectral Reflectance of Duckweed (Lemna Gibba L.) Fronds Exposed to Ethylene Glycol

NASA Technical Reports Server (NTRS)

Dong, Weijin; Carter, Gregory A.; Barber, John T.

2001-01-01

When duckweed (Lemna Gibba L.) fronds are exposed to ethylene glycol (EG) anatomy is altered, allowing an increase in water uptake that causes a darkening of frond appearance. Spectroradiometry was used to quantify changes in frond reflectance that occurred throughout the 400-850 nm spectrum under various EG concentrations and exposure times. The threshold concentration of EG at which a reflectance change could be detected was between 35 and 40 mM, approximately the same as by visual observation. EG-induced changes in frond reflectance were maximum at concentrations of 50 mM or greater. Reflectance changes were detectable within 24h of exposure to 100 mM EG,2-3 days prior to changes in frond appearance. The spectroradiometry of duckweed may serve as a rapid and sensitive technique for detection of ecosystem exposure to EG and perhaps other stress agents.

Occurrence of dichloroacetamide herbicide safeners and co-applied herbicides in midwestern U.S. streams

USGS Publications Warehouse

Woodward, Emily; Hladik, Michelle; Kolpin, Dana W.

2018-01-01

Dichloroacetamide safeners (e.g., AD-67, benoxacor, dichlormid, and furilazole) are co-applied with chloroacetanilide herbicides to protect crops from herbicide toxicity. While such safeners have been used since the early 1970s, there are minimal data about safener usage, occurrence in streams, or potential ecological effects. This study focused on one of these research gaps, occurrence in streams. Seven Midwestern U.S. streams (five in Iowa and two in Illinois), with extensive row-crop agriculture, were sampled at varying frequencies from spring 2016 through summer 2017. All four safeners were detected at least once; furilazole was the most frequently detected (31%), followed by benoxacor (29%), dichlormid (15%), and AD-67 (2%). The maximum concentrations ranged from 42 to 190 ng/L. Stream detections and concentrations of safeners appear to be driven by a combination of timing of application (spring following herbicide application) and precipitation events. Detected concentrations were below known toxicity levels for aquatic organisms.

Seasonal exposures to triazine and other pesticides in surface waters in the western Highveld corn-production region in South Africa

USGS Publications Warehouse

Du Preez, L.H.; Jansen Van Rensburg, P.J.; Jooste, A.M.; Carr, J.A.; Giesy, J.P.; Gross, T.S.; Kendall, R.J.; Smith, E.E.; Van Der Kraak, G.; Solomon, K.R.

2005-01-01

The objective of this study was to characterize concentrations of atrazine, terbuthylazine, and other pesticides in amphibian habitats in surface waters of a corn-production area of the western Highveld region (North-West Province) of South Africa. The study was conducted from November 2001 to June 2002, coinciding with the corn-production season. Pesticide residues were measured at regular intervals in surface water from eight ponds, three in a non-corn-growing area (NCGA) and five within the corn-growing area (CGA). Measured atrazine concentrations differed significantly among sites and between samples. In the five CGA sites, the maximum atrazine concentrations measured during the study ranged from 1.2 to 9.3 ??g/L. Although no atrazine was recorded as being applied in the catchment of the three NCGA sites, maximum concentrations from 0.39 to 0.84 ??g/L were measured during the study, possibly as a result of atmospheric transport. Maximum measured concentrations of terbuthylazine ranged from 1.22 to 2.1 ??g/L in the NCGA sites and from 1.04 to 4.1 ??g/L in the CGA sites. The source of terbuthylazine in the NCGA sites may have been in use other than in corn. The triazine degradation products, deisopropylatrazine (DIA) and deethylatrazine (DEA) and diaminochlorotriazine (DACT) were also found in water from both the CGA and NCGA sites. Concentrations of DIA were ??? 1 ??g/L throughout the season, while DEA concentrations were mostly 2 ??g/L in some locations. Concentrations of DACT were highly variable (LOD to 8 ??g/L) both before and after planting and application, suggesting that they resulted from historical use of triazines in the area. Other herbicides such as simazine and acetochlor were only detected infrequently and pesticides such as S-metolachlor, cypermethrin, monocrotophos, and terbuphos, known to be used in the CGA, were not detected in any of the samples. Because of dilution by higher than normal rainfall in the study period, these concentrations may not be predictive of those in years of normal rainfall. ?? 2004 Elsevier Ltd. All rights reserved.

Occurrence and relationship of organophosphorus insecticides and their degradation products in the atmosphere in Western Canada agricultural regions.

PubMed

Raina, Renata; Hall, Patricia; Sun, Lina

2010-11-15

This paper presents the atmospheric occurrence and seasonal variations of the most frequently detected organophosphorus insecticides (OPs) and their OP oxon degradation products at Bratt's Lake, Saskatchewan in the Canadian Prairies (April 2003 to March 2004, January-December, 2005) and at Abbotsford in the Lower Frazer Valley (LFV) of British Columbia from May 2004 to December, 2005. During 2005 there were 10 OPs, 8 OP oxons, and 6 other OP degradation products measured. The most frequently detected OPs were chlorpyrifos, malathion, and diazinon. At Bratt's Lake the highest atmospheric concentrations were observed for chlorpyrifos, with maximum concentrations observed during July and August in 2003 showing much higher concentrations than those from 2005. This was related to its usage for grasshopper control in the province. At Abbotsford, diazinon and malathion were observed in much higher atmospheric concentrations than chlorpyrifos. Concentrations reached maximum in spring for diazinon and summer for malathion. This study is the first reported study of seasonal variations of OP oxons with their parent OP. Chlorpyrifos oxon concentrations during July were generally low, indicating strong local source contributions. The chlorpyrifos oxon/chlorpyrifos ratio and diazinon oxon/diazinon ratio showed a strong seasonal variation with increasing ratio from spring to summer which was attributed to increasing sunlight hours. Malathion oxon/mathion at both sites was similar and relatively constant throughout the year. The oxon/thion ratio represents a good indicator of age of source or contributions from local versus regional atmospheric sources.

Occurrence of pesticides in surface water and sediments from three central California coastal watersheds, 2008-2009

USGS Publications Warehouse

Smalling, Kelly L.; Orlando, James L.

2011-01-01

Water and sediment (bed and suspended) were collected from January 2008 through October 2009 from 12 sites in 3 of the largest watersheds along California's Central Coast (Pajaro, Salinas, and Santa Maria Rivers) and analyzed for a suite of pesticides by the U.S. Geological Survey. Water samples were collected in each watershed from the estuaries and major tributaries during 4 storm events and 11 dry season sampling events in 2008 and 2009. Bed sediments were collected from depositional zones at the tributary sampling sites three times over the course of the study. Suspended sediment samples were collected from the major tributaries during the four storm events and in the tributaries and estuaries during three dry season sampling events in 2009. Water samples were analyzed for 68 pesticides using gas chromatography/mass spectrometry. A total of 38 pesticides were detected in 144 water samples, and 13 pesticides were detected in more than half the samples collected over the course of the study. Dissolved pesticide concentrations ranged from below their method detection limits to 36,000 nanograms per liter (boscalid). The most frequently detected pesticides in water from all the watersheds were azoxystrobin, boscalid, chlorpyrifos, DCPA, diazinon, oxyfluorfen, prometryn, and propyzamide, which were found in more than 80 percent of the samples. On average, detection frequencies and concentrations were higher in samples collected during winter storm events compared to the summer dry season. With the exception of the fungicide, myclobutanil, the Santa Maria estuary watershed exhibited higher pesticide detection frequencies than the Pajaro and Salinas watersheds. Bed and suspended sediment samples were analyzed for 55 pesticides using accelerated solvent extraction, gel permeation chromatography for sulfur removal, and carbon/alumina stacked solid-phase extraction cartridges to remove interfering sediment matrices. In bed sediment samples, 17 pesticides were detected including pyrethroid and organophosphate (OP) insecticides, p,p'-DDT and its degradates, as well as several herbicides. The only pesticides detected more than half the time were p,p'-DDD, p,p'-DDE, and p,p'-DDT. Maximum pesticide concentrations ranged from less than their respective method detection limits to 234 micrograms per kilogram (p,p'-DDE). Four pyrethroids (bifenthrin, &# 955;-cyhalothrin, permethrin, and &# 964;-fluvalinate) were detected in bed sediment samples, though concentrations were relatively low (less than 10 microgram per kilogram). The greatest number of pesticides were detected in samples collected from Lower Orcutt Creek, the major tributary to the Santa Maria estuary. In suspended sediment samples, 19 pesticides were detected, and maximum concentrations ranged from less than the method detection limits to 549 micrograms per kilogram (chlorpyrifos). The most frequently detected pesticides were p,p'-DDE (49 percent), p,p'-DDT (38 percent), and chlorpyrifos (32 percent). During storm events, 19 pesticides were detected in suspended sediment samples compared to 10 detected during the dry season. Pesticide concentrations commonly were higher in suspended sediments during storm events than during the dry season, as well.

Fluorescence chemodosimeter for dopamine based on the inner filter effect of the in situ generation of silver nanoparticles and fluorescent dye

NASA Astrophysics Data System (ADS)

Uppa, Yuwapon; Ngamdee, Kessarin; Promarak, Vinich; Ngeontae, Wittaya

2018-07-01

A new strategy for the sensitive and selective detection of dopamine (DA) was proposed. The chemodosimeter design was based on the measurement of the fluorescent quenching of fluorescein dye caused by the in situ generation of silver nanoparticles (AgNPs). The AgNPs can be simply generated by a reaction between DA and Ag+ in the presence of polymethacrylic acid (PMAA). In addition, the generated AgNPs possess the maximum surface plasmon resonance (SPR) at 440 nm and an increase in the SPR intensity with an increasing DA concentration. Basically, fluorescein dye can emit the fluorescent intensity maximum at 513 nm with excitation at 487 nm. Thus, fluorescent quenching was achieved due to an inner filter effect from the overlap between the excitation spectrum of the fluorescein dye and the SPR spectrum of the generated AgNPs. The degree of fluorescent quenching linearly depends on the number of generated AgNPs that can be directly related to the concentration of DA. The proposed chemodosimeter can be used to detect DA in a working linear concentration range of 1.0-5.0 μM at a detection limit of 10.6 nM. This chemodosimeter was successfully applied to determine DA in a real urine sample and a dopamine injection formulation with satisfactory results.

Naturally occurring contaminants in the Piedmont and Blue Ridge crystalline-rock aquifers and Piedmont Early Mesozoic basin siliciclastic-rock aquifers, eastern United States, 1994–2008

USGS Publications Warehouse

Chapman, Melinda J.; Cravotta, Charles A.; Szabo, Zoltan; Lindsay, Bruce D.

2013-01-01

Groundwater quality and aquifer lithologies in the Piedmont and Blue Ridge Physiographic Provinces in the eastern United States vary widely as a result of complex geologic history. Bedrock composition (mineralogy) and geochemical conditions in the aquifer directly affect the occurrence (presence in rock and groundwater) and distribution (concentration and mobility) of potential naturally occurring contaminants, such as arsenic and radionuclides, in drinking water. To evaluate potential relations between aquifer lithology and the spatial distribution of naturally occurring contaminants, the crystalline-rock aquifers of the Piedmont and Blue Ridge Physiographic Provinces and the siliciclastic-rock aquifers of the Early Mesozoic basin of the Piedmont Physiographic Province were divided into 14 lithologic groups, each having from 1 to 16 lithochemical subgroups, based on primary rock type, mineralogy, and weathering potential. Groundwater-quality data collected by the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Program from 1994 through 2008 from 346 wells and springs in various hydrogeologic and land-use settings from Georgia through New Jersey were compiled and analyzed for this study. Analyses for most constituents were for filtered samples, and, thus, the compiled data consist largely of dissolved concentrations. Concentrations were compared to criteria for protection of human health, such as U.S. Environmental Protection Agency (USEPA) drinking water maximum contaminant levels and secondary maximum contaminant levels or health-based screening levels developed by the USGS NAWQA Program in cooperation with the USEPA, the New Jersey Department of Environmental Protection, and Oregon Health & Science University. Correlations among constituent concentrations, pH, and oxidation-reduction (redox) conditions were used to infer geochemical controls on constituent mobility within the aquifers. Of the 23 trace-element constituents evaluated, arsenic, manganese, and zinc were detected in one or more water samples at concentrations greater than established human health-based criteria. Arsenic concentrations typically were less than 1 microgram per liter (µg/L) in most groundwater samples; however, concentrations of arsenic greater than 1 µg/L frequently were detected in groundwater from clastic lacustrine sedimentary rocks of the Early Mesozoic basin aquifers and from metamorphosed clastic sedimentary rocks of the Piedmont and Blue Ridge crystalline rock aquifers. Groundwater from these rock units had elevated pH compared to other rock units evaluated in this study. Of the nine samples for which arsenic concentration was greater than 10 µg/L, six were classified as oxic and three as anoxic, and seven had pH of 7.2 or greater. Manganese concentrations typically were less than 10 µg/L in most samples; however, 8.3 percent of samples from the Piedmont and Blue Ridge crystalline-rock aquifers and 3.0 percent of samples from the Early Mesozoic basin siliciclastic rock aquifers had manganese concentrations greater than the 300-µg/L health-based screening level. The positive correlation of manganese with iron and ammonia and the negative correlation of manganese with dissolved oxygen and nitrate are consistent with the reductive dissolution of manganese oxides in the aquifer. Zinc concentrations typically were less than 10 µg/L in the groundwater samples considered in the study, but 0.4 percent and 5.5 percent of the samples had concentrations greater than the health-based screening level of 2,000 µg/L and one-tenth of the health-based screening level, respectively. The mean rank concentration of zinc in groundwater from the quartz-rich sedimentary rock lithologic group was greater than that for other lithologic groups even after eliminating samples collected from wells constructed with galvanized casing. Approximately 90 percent of 275 groundwater samples had radon-222 concentrations that were greater than the proposed alternative maximum contaminant level of 300 picocuries per liter. In contrast, only 2.0 percent of 98 samples had combined radium (radium-226 plus radium-228) concentrations greater than the maximum contaminant level of 5.0 picocuries per liter, and 0.6 percent of 310 samples had uranium concentrations greater than the maximum contaminant level of 30 µg/L. Radon concentrations were highest in the Piedmont and Blue Ridge crystalline-rock aquifers, especially in granite, and elevated median concentrations were noted in the Piedmont Early Mesozoic basin aquifers, but without the extreme maximum concentrations found in the crystalline rocks (granites). Although the siliciclastic lithologies had a greater frequency of elevated uranium concentrations, radon and radium were commonly detected in water from both siliciclastic and crystalline lithologies. Uranium concentrations in groundwater from clastic sedimentary and clastic lacustrine/evaporite sedimentary lithologic groups within the Early Mesozoic basin aquifers, which had median concentrations of 3.6 and 3.1 µg/L, respectively, generally were higher than concentrations for other siliciclastic lithologic groups, which had median concentrations less than 1 µg/L. Although 89 percent of the 260 samples from crystalline-rock aquifers had uranium concentrations less than 1 µg/L, 0.8 percent had uranium concentrations greater than the 30-µg/L maximum contaminant level, and 6.5 percent had concentrations greater than 3 µg/L.

Short communication: concentrations of nonesterified fatty acids and β-hydroxybutyrate in dairy cows are not well correlated during the transition period.

PubMed

McCarthy, M M; Mann, S; Nydam, D V; Overton, T R; McArt, J A A

2015-09-01

The objective was to use longitudinal data of blood nonesterified fatty acids (NEFA) and β-hydroxybutyrate (BHBA) concentrations to describe the relationship between NEFA and BHBA in dairy cows during the periparturient period. Blood NEFA and BHBA concentration data collected from d 21 prepartum to 21 postpartum for 269 multiparous Holstein cows were selected from 4 different studies carried out within our research groups. Overall, NEFA concentrations were increased beginning near parturition with a relatively steady elevation of NEFA through d 9, after which concentrations gradually decreased. Prepartum BHBA concentrations began to increase beginning several days before parturition, continued to increase during the first week after parturition, and remained elevated through d 21 postpartum. Of the 269 cows included in the data set, 117 cows (43.5%) had at least one postpartum hyperketonemic event (BHBA ≥1.2mmol/L), and 202 cows (75.1%) had at least one event of elevated postpartum NEFA concentrations (≥0.70mmol/L) between 3 and 21 d in milk. Area under the curve (AUC) was used to investigate relationships between metabolites over time. Overall, the correlations between transition period NEFA and BHBA AUC were weak. We detected a negative correlation between prepartum BHBA AUC and postpartum NEFA AUC (r=-0.26). A positive correlation existed between postpartum NEFA AUC and postpartum BHBA AUC; however, the correlation coefficient was low (r=0.26). Large variation was found between the day of maximum NEFA concentration within the first 21 d in milk and day of maximum BHBA concentration for the same period. The mean and median times of maximum NEFA concentration were 6.8 and 6 d, respectively, whereas the mean and median times of maximum BHBA were 9.6 and 8 d, respectively; however, the range in days for both the mean and median day of maximum concentrations was very large. Overall, our data set indicates a weak relationship between blood concentrations of NEFA and BHBA during the periparturient period of dairy cows, suggesting that elevated concentrations of one should not be extrapolated to suggest elevated concentrations of the other metabolite. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Toxicological relevance of emerging contaminants for drinking water quality.

PubMed

Schriks, Merijn; Heringa, Minne B; van der Kooi, Margaretha M E; de Voogt, Pim; van Wezel, Annemarie P

2010-01-01

The detection of many new compounds in surface water, groundwater and drinking water raises considerable public concern, especially when human health based guideline values are not available it is questioned if detected concentrations affect human health. In an attempt to address this question, we derived provisional drinking water guideline values for a selection of 50 emerging contaminants relevant for drinking water and the water cycle. For only 10 contaminants, statutory guideline values were available. Provisional drinking water guideline values were based upon toxicological literature data. The maximum concentration levels reported in surface waters, groundwater and/or drinking water were compared to the (provisional) guideline values of the contaminants thus obtained, and expressed as Benchmark Quotient (BQ) values. We focused on occurrence data in the downstream parts of the Rhine and Meuse river basins. The results show that for the majority of compounds a substantial margin of safety exists between the maximum concentration in surface water, groundwater and/or drinking water and the (provisional) guideline value. The present assessment therefore supports the conclusion that the majority of the compounds evaluated pose individually no appreciable concern to human health. (c) 2009 Elsevier Ltd. All rights reserved.

Groundwater Quality in Central New York, 2007

USGS Publications Warehouse

Eckhardt, David A.V.; Reddy, J.E.; Shaw, Stephen B.

2009-01-01

Water samples were collected from 7 production wells and 28 private residential wells in central New York from August through December 2007 and analyzed to characterize the chemical quality of groundwater. Seventeen wells are screened in sand and gravel aquifers, and 18 are finished in bedrock aquifers. The wells were selected to represent areas of greatest groundwater use and to provide a geographical sampling from the 5,799-square-mile study area. Samples were analyzed for 6 physical properties and 216 constituents, including nutrients, major inorganic ions, trace elements, radionuclides, pesticides, volatile organic compounds, phenolic compounds, organic carbon, and 4 types of bacteria. Results indicate that groundwater used for drinking supply is generally of acceptable quality, although concentrations of some constituents or bacteria exceeded at least one drinking-water standard at several wells. The cations detected in the highest concentrations were calcium, magnesium, and sodium; anions detected in the highest concentrations were bicarbonate, chloride, and sulfate. The predominant nutrients were nitrate and ammonia, but no nutrients exceeded Maximum Contaminant Levels (MCLs). The trace elements barium, boron, lithium, and strontium were detected in every sample; the trace elements present in the highest concentrations were barium, boron, iron, lithium, manganese, and strontium. Fifteen pesticides, including seven pesticide degradates, were detected in water from 17 of the 35 wells, but none of the concentrations exceeded State or Federal MCLs. Sixteen volatile organic compounds were detected in water from 15 of the 35 wells. Nine analytes and three types of bacteria were detected in concentrations that exceeded Federal and State drinking-water standards, which typically are identical. One sample had a water color that exceeded the U.S. Environmental Protection Agency (USEPA) Secondary Maximum Contaminant Level (SMCL) and the New York State MCL of 10 color units. Sulfate concentrations exceeded the USEPA SMCL and the New York State MCL of 250 milligrams per liter (mg/L) in two samples, and chloride concentrations exceeded the USEPA SMCL and the New York State MCL of 250 mg/L in two samples. Sodium concentrations exceeded the USEPA Drinking Water Health Advisory of 60 mg/L in eight samples. Iron concentrations exceeded the USEPA SMCL and the New York State MCL of 300 micrograms per liter (ug/L) in 10 filtered samples. Manganese exceeded the USEPA SMCL of 50 ug/L in 10 filtered samples and the New York State MCL of 300 ug/L in 1 filtered sample. Barium exceeded the MCL of 2,000 ug/L in one sample, and aluminum exceeded the SMCL of 50 ug/L in three samples. Radon-222 exceeded the proposed USEPA MCL of 300 picocuries per liter in 12 samples. One sample from a private residential well had a trichloroethene concentration of 50.8 ug/L, which exceeded the MCL of 5 ug/L. Any detection of coliform bacteria indicates a potential violation of New York State health regulations; total coliform bacteria were detected in 19 samples, and fecal coliform bacteria were detected in one sample. The plate counts for heterotrophic bacteria exceeded the MCL (500 colony-forming units per milliliter) in three samples.

Odor Detection by Humans of Lineal Aliphatic Aldehydes and Helional as Gauged by Dose–Response Functions

PubMed Central

Abraham, Michael H.

2010-01-01

We have measured concentration detection (i.e., psychometric) functions to determine the odor detectability of homologous aliphatic aldehydes (propanal, butanal, hexanal, octanal, and nonanal) and helional. Subjects (16 ≤ n ≤ 18) used a 3-alternative forced-choice procedure against carbon-filtered air (blanks), under an ascending concentration approach. Generation, delivery, and control of each vapor were achieved via an 8-station vapor delivery device. Gas chromatography served to quantify the concentrations presented. Group and individual functions were modeled by a sigmoid (logistic) equation. Odor detection thresholds (ODTs) were defined as the concentration producing a detectability (P) halfway (P = 0.5) between chance (P = 0.0) and perfect detection (P = 1.0). ODTs decreased with carbon chain length: 2.0, 0.46, 0.33, and 0.17 ppb, respectively, from propanal to octanal, but the threshold increased for nonanal (0.53 ppb), revealing maximum sensitivity for the 8-carbon member. The strong olfactory receptor (OR) ligands octanal and helional (0.14 ppb) showed the lowest thresholds. ODTs fell at the lower end of previously reported values. Interindividual variability (ODT ratios) amounted to a factor ranging from 10 to 50, lower than typically reported, and was highest for octanal and hexanal. The behavioral dose–response functions emerge at concentrations 2–5 orders of magnitude lower than those required for functions tracing the activation of specific human ORs by the same aldehydes in cell/molecular studies, after all functions were expressed as vapor concentrations. PMID:20190010

Comparison of MTBE concentrations in groundwater of urban and nonurban areas in Germany.

PubMed

Kolb, Axel; Püttmann, Wilhelm

2006-11-01

The occurrence of the gasoline oxygenate methyl tert-butyl ether (MTBE) in groundwater samples from known fuel-contaminated sites (n=29 samples), nonurban (n=74) and urban sites (n=67) in Germany was investigated. The analyses revealed detection frequencies of 58% (contaminated sites), 24% (nonurban sites) and 63% (urban sites) at a detection limit of 0.01 microgL(-1). Median (maximum) MTBE concentrations were calculated for nonurban and urban samples as 0.18 microgL(-1) (2.2 microgL(-1)) and 0.06 microgL(-1) (48 microg L(-1)). The data from nonurban samples revealed MTBE detections mainly at public supply wells with higher pumping rates than monitoring wells. MTBE was more frequently detected in urban samples, most probably due to the higher atmospheric input and direct liquid emissions from motorways or gas stations. Higher concentrations above 1.0 microgL(-1) in urban areas were found in wells located at industrial sites, where also a MTBE plume was accidentally detected during the study. The prevalence of MTBE in shallow aquifers was comparable to those in the USA.

Simple detection of residual enrofloxacin in meat products using microparticles and biochips.

PubMed

Ha, Mi-Sun; Chung, Myung-Sub; Bae, Dong-Ho

2016-05-01

A simple and sensitive method for detecting enrofloxacin, a major veterinary fluoroquinolone, was developed. Monoclonal antibody specific for enrofloxacin was immobilised on a chip and fluorescent dye-labelled microparticles were covalently bound to the enrofloxacin molecules. Enrofloxacin in solution competes with the microparticle-immobilised enrofloxacin (enroMPs) to bind to the antibody on the chip. The presence of enrofloxacin was verified by detecting the fluorescence of enrofloxacin-bound microparticles. Under optimum conditions, a high dynamic range was achieved at enrofloxacin concentrations ranging from 1 to 1000 μg kg(-1). The limits of detection and quantification for standard solutions were 5 and 20 μg kg(-1) respectively, which are markedly lower than the maximum residue limit. Using simple extraction methods, recoveries from fortified beef, pork and chicken samples were 43.4-62.3%. This novel method also enabled approximate quantification of enrofloxacin concentration: the enroMP signal intensity decreased with increasing enrofloxacin concentration. Because of its sensitivity, specificity, simplicity and rapidity, the method described herein will facilitate the detection and approximate quantification of enrofloxacin residues in foods in a high-throughput manner.

Inhibition of recombinase polymerase amplification by background DNA: a lateral flow-based method for enriching target DNA.

PubMed

Rohrman, Brittany; Richards-Kortum, Rebecca

2015-02-03

Recombinase polymerase amplification (RPA) may be used to detect a variety of pathogens, often after minimal sample preparation. However, previous work has shown that whole blood inhibits RPA. In this paper, we show that the concentrations of background DNA found in whole blood prevent the amplification of target DNA by RPA. First, using an HIV-1 RPA assay with known concentrations of nonspecific background DNA, we show that RPA tolerates more background DNA when higher HIV-1 target concentrations are present. Then, using three additional assays, we demonstrate that the maximum amount of background DNA that may be tolerated in RPA reactions depends on the DNA sequences used in the assay. We also show that changing the RPA reaction conditions, such as incubation time and primer concentration, has little effect on the ability of RPA to function when high concentrations of background DNA are present. Finally, we develop and characterize a lateral flow-based method for enriching the target DNA concentration relative to the background DNA concentration. This sample processing method enables RPA of 10(4) copies of HIV-1 DNA in a background of 0-14 μg of background DNA. Without lateral flow sample enrichment, the maximum amount of background DNA tolerated is 2 μg when 10(6) copies of HIV-1 DNA are present. This method requires no heating or other external equipment, may be integrated with upstream DNA extraction and purification processes, is compatible with the components of lysed blood, and has the potential to detect HIV-1 DNA in infant whole blood with high proviral loads.

Occurrence and concentrations of pharmaceutical compounds in deep groundwater used for public drinking-water supply in California

USGS Publications Warehouse

Fram, Miranda S.; Belitz, Kenneth

2011-01-01

Pharmaceutical compounds were detected at low concentrations in 2.3% of 1231 samples of groundwater (median depth to top of screened interval in wells = 61 m) used for public drinking-water supply in California. Samples were collected statewide for the California State Water Resources Control Board's Groundwater Ambient Monitoring and Assessment (GAMA) Program. Of 14 pharmaceutical compounds analyzed, 7 were detected at concentrations greater than or equal to method detection limits: acetaminophen (used as an analgesic, detection frequency 0.32%, maximum concentration 1.89 μg/L), caffeine (stimulant, 0.24%, 0.29 μg/L), carbamazepine (mood stabilizer, 1.5%, 0.42 μg/L), codeine (opioid analgesic, 0.16%, 0.214 μg/L), p-xanthine (caffeine metabolite, 0.08%, 0.12 μg/L), sulfamethoxazole (antibiotic, 0.41%, 0.17 μg/L), and trimethoprim (antibiotic, 0.08%, 0.018 μg/L). Detection frequencies of pesticides (33%), volatile organic compounds not including trihalomethanes (23%), and trihalomethanes (28%) in the same 1231 samples were significantly higher. Median detected concentration of pharmaceutical compounds was similar to those of volatile organic compounds, and higher than that of pesticides. Pharmaceutical compounds were detected in 3.3% of the 855 samples containing modern groundwater (tritium activity > 0.2 TU). Pharmaceutical detections were significantly positively correlated with detections of urban-use herbicides and insecticides, detections of volatile organic compounds, and percentage of urban land use around wells. Groundwater from the Los Angeles metropolitan area had higher detection frequencies of pharmaceuticals and other anthropogenic compounds than groundwater from other areas of the state with similar proportions of urban land use. The higher detection frequencies may reflect that groundwater flow systems in Los Angeles area basins are dominated by engineered recharge and intensive groundwater pumping.

Faces of a changing climate: semi-quantitative multi-mycotoxin analysis of grain grown in exceptional climatic conditions in Norway.

PubMed

Uhlig, Silvio; Eriksen, Gunnar Sundstøl; Hofgaard, Ingerd Skow; Krska, Rudolf; Beltrán, Eduardo; Sulyok, Michael

2013-09-27

Recent climatological research predicts a significantly wetter climate in Southern Norway as a result of global warming. Thus, the country has already experienced unusually wet summer seasons in the last three years (2010-2012). The aim of this pilot study was to apply an existing multi-analyte LC-MS/MS method for the semi-quantitative determination of 320 fungal and bacterial metabolites in Norwegian cereal grain samples from the 2011 growing season. Such knowledge could provide important information for future survey and research programmes in Norway. The method includes all regulated and well-known mycotoxins such as aflatoxins, trichothecenes, ochratoxin A, fumonisins and zearalenone. In addition, a wide range of less studied compounds are included in the method, e.g., Alternaria toxins, ergot alkaloids and other metabolites produced by fungal species within Fusarium, Penicillium and Aspergillus. Altogether, 46 metabolites, all of fungal origin, were detected in the 76 barley, oats and wheat samples. The analyses confirmed the high prevalence and relatively high concentrations of type-A and -B trichothecenes (e.g., deoxynivalenol up to 7230 µg/kg, HT-2 toxin up to 333 µg/kg). Zearalenone was also among the major mycotoxins detected (maximum concentration 1670 µg/kg). Notably, several other Fusarium metabolites such as culmorin, 2-amino-14,16-dimethyloctadecan-3-ol and avenacein Y were co-occurring. Furthermore, the most prevalent Alternaria toxin was alternariol with a maximum concentration of 449 µg/kg. A number of Penicillium and Aspergillus metabolites were also detected in the samples, e.g., sterigmatocystin in concentrations up to 20 µg/kg.

Ground-water quality in the Lake Champlain basin, New York, 2004

USGS Publications Warehouse

Nystrom, Elizabeth A.

2006-01-01

Water samples were collected from 11 public-supply wells and 11 private domestic wells in the Lake Champlain basin in New York during the fall of 2004 to characterize the chemical quality of ground water. Wells were selected for sampling based on location and focused on areas of greatest ground-water use. Samples were analyzed for 219 physical properties and constituents, including inorganic compounds, nutrients, metals, radionuclides, pesticides and pesticide degradates, volatile organic compounds, and bacteria. Sixty-eight constituents were detected at concentrations above laboratory reporting levels. The cation and anion with the highest median concentration were calcium (34.8 mg/L) bicarbonate (134 mg/L), respectively. The predominant nutrient was nitrate, which was detected in 14 (64 percent) of the 22 samples. The two metals with the highest median concentrations were iron (175 ?g/L) and strontium (124 ?g/L); concentrations of iron, manganese, aluminum, and zinc exceeded U.S. Environmental Protection Agency secondary drinking-water standards in one or more samples. Radon concentrations were less than 1,000 picocuries per liter (pCi/L) in most samples, but concentrations as high as 6,900 pCi/L were detected and, in eight samples, exceeded the U.S. Environmental Protection Agency proposed maximum contaminant level (300 pCi/L) for radon. The most frequently detected pesticides were degradates of the broadleaf herbicides metolachlor, alachlor, and atrazine. Volatile organic compounds were detected in only three samples; those that were detected typically were fuel oxygenates, such as methyl tert-butyl ether. Coliform bacteria were detected in four samples, two of which also tested positive for E. coli.

Maximum entropy estimation of a Benzene contaminated plume using ecotoxicological assays.

PubMed

Wahyudi, Agung; Bartzke, Mariana; Küster, Eberhard; Bogaert, Patrick

2013-01-01

Ecotoxicological bioassays, e.g. based on Danio rerio teratogenicity (DarT) or the acute luminescence inhibition with Vibrio fischeri, could potentially lead to significant benefits for detecting on site contaminations on qualitative or semi-quantitative bases. The aim was to use the observed effects of two ecotoxicological assays for estimating the extent of a Benzene groundwater contamination plume. We used a Maximum Entropy (MaxEnt) method to rebuild a bivariate probability table that links the observed toxicity from the bioassays with Benzene concentrations. Compared with direct mapping of the contamination plume as obtained from groundwater samples, the MaxEnt concentration map exhibits on average slightly higher concentrations though the global pattern is close to it. This suggest MaxEnt is a valuable method to build a relationship between quantitative data, e.g. contaminant concentrations, and more qualitative or indirect measurements, in a spatial mapping framework, which is especially useful when clear quantitative relation is not at hand. Copyright © 2012 Elsevier Ltd. All rights reserved.

Product separator

DOEpatents

Welsh, Robert A.; Deurbrouck, Albert W.

1976-01-20

A secondary light sensitive photoelectric product separator for use with a primary product separator that concentrates a material so that it is visually distinguishable from adjacent materials. The concentrate separation is accomplished first by feeding the material onto a vibratory inclined surface with a liquid flow, such as a wet concentrating table. Vibrations generally perpendicular to the stream direction of flow cause the concentrate to separate from its mixture according to its color. When the concentrate and its surrounding stream reach the recovery end of the table, a detecting device notes the line of color demarcation and triggers a signal if it differs from a normal condition. If no difference is noted nothing moves on the second separator. However, if a difference is detected in the constant monitoring of the color line's location, a product splitter and recovery unit normally positioned near the color line at the recovery end, moves to a new position. In this manner the selected separated concentrate is recovered at a maximum rate regardless of variations in the flow stream or other conditions present.

Contaminants of emerging concern in fresh leachate from landfills in the conterminous United States

USGS Publications Warehouse

Masoner, Jason R.; Kolpin, Dana W.; Furlong, Edward T.; Cozzarelli, Isabelle M.; Gray, James L.; Schwab, Eric A.

2014-01-01

To better understand the composition of contaminants of emerging concern (CECs) in landfill leachate, fresh leachate from 19 landfills was sampled across the United States during 2011. The sampled network included 12 municipal and 7 private landfills with varying landfill waste compositions, geographic and climatic settings, ages of waste, waste loads, and leachate production. A total of 129 out of 202 CECs were detected during this study, including 62 prescription pharmaceuticals, 23 industrial chemicals, 18 nonprescription pharmaceuticals, 16 household chemicals, 6 steroid hormones, and 4 plant/animal sterols. CECs were detected in every leachate sample, with the total number of detected CECs in samples ranging from 6 to 82 (median = 31). Bisphenol A (BPA), cotinine, and N,N-diethyltoluamide (DEET) were the most frequently detected CECs, being found in 95% of the leachate samples, followed by lidocaine (89%) and camphor (84%). Other frequently detected CECs included benzophenone, naphthalene, and amphetamine, each detected in 79% of the leachate samples. CEC concentrations spanned six orders of magnitude, ranging from ng L−1 to mg L−1. Industrial and household chemicals were measured in the greatest concentrations, composing more than 82% of the total measured CEC concentrations. Maximum concentrations for three household and industrial chemicals, para-cresol (7020000 ng L−1), BPA (6380000 ng L−1), and phenol (1550000 ng L−1), were the largest measured, with these CECs composing 70% of the total measured CEC concentrations. Nonprescription pharmaceuticals represented 12%, plant/animal sterols 4%, prescription pharmaceuticals 1%, and steroid hormones <1% of the total measured CEC concentrations. Leachate from landfills in areas receiving greater amounts of precipitation had greater frequencies of CEC detections and concentrations in leachate than landfills receiving less precipitation.

Field screening of water quality, bottom sediment, and biota associated with irrigation drainage in the Yuma Valley, Arizona, 1995

USGS Publications Warehouse

Tadayon, Saeid; King, K.A.; Andrews, Brenda; Roberts, William

1997-01-01

Because of concerns expressed by the U.S. Congress and the environmental community, the Department of the Interior began a program in late 1985 to identify the nature and extent of water-quality problems induced by irrigation that might exist in the western States. Surface water, bottom sediment, and biota were collected from March through September 1995 along the lower Colorado River and in agricultural drains at nine sites in the Yuma Valley, Arizona, and analyzed for selected inorganic and organic constituents. Analyses of water, bottom sediment, and biota were completed to determine if irrigation return flow has caused, or has the potential to cause, harmful effects on human health, fish, and wildlife in the study area. Concentrations of dissolved solids in surface-water samples collected in March generally did not vary substantially from surface-water samples collected in June. Concentrations of dissolved solids ranged from 712 to 3,000 milligrams per liter and exceeded the U.S. Environmental Protection Agency secondary maximum contaminant level of 500 milligrams per liter for drinking water. Concentrations of chloride in 9 of 18 water samples and concentrations of sulfate in 16 of 18 water samples exceeded the U.S. Environmental Protection Agency secondary maximum contaminant level of 250 milligrams per liter for drinking water. Calcium and sodium were the dominant cations, and chloride and sulfate were the dominant anions. The maximum selenium concentration of 8 micrograms per liter exceeded the U.S. Environmental Protection Agency aquatic-life chronic criterion of 5 micrograms per liter. Concentrations of lead in 7 of 18 water samples and concentrations of mercury in 4 of 18 water samples exceeded the aquatic-life cronic criteria of 3.2 and 0.012 micrograms per liter, respectively. Concentrations of antimony, beryllium, cadmium, and silver in the water samples were below analytical reporting limits. Arsenic was detected in 3 of 9 bottom-sediment samples, and concentrations ranged from 11 to 16 micrograms per gram. Concentrations ofaluminum, beryllium, boron, copper, lead, and zinc were highest in samples from Main Drain at southerly international boundary near San Luis, Arizona. Selenium was detected in all bottom-sediment samples, and concentrations ranged from 0.1 to 0.7 micrograms per gram. Concentrations of cadmium, europium, homium, mercury, molybdenum, silver, tantalum, tin, and uranium were below analytical reporting limits in the bottom-sediment samples. Concentrations of trace elements in bottom-sediment samples were within the ranges found in a study of soils of the western United States and did not indicate a significant accumulation of these constituents. p,p'Dichlorodiphenyldichloroethylene (commonly referred to as p,-p'-DDE) was detected in one bottom-sediment sample at a concentration of 1.4 micrograms per gram. No other organochlorine compounds were detected in the bottom-sediment samples. DDE was present in all fish and bird samples. Almost one-half of the fish samples contained DDE residues that were two times higher than the mean calculated for a national study in 1984-85. Twenty-tree percent of the fish contained more than three times the national mean. Fish from downstream parts of the Main Drain had the highest concentrations of DDE. Although concentrations of DDE in fish and in bird carcasses and eggs were above background levels, residues generally were below thresholds associated with chronic poisoning and reproductive problems in figh and wildlife. Concentrations of 18 trace elements were detected in cattail (Typha sp.) roots, freshwater clam (Corbicula fluminea), fish, and bird samples. Selenium in most fish and in livers of red-winged (Agelaius phoeniceus) and yellow-headed (Xanthocephalus xanthocephalus) blackbirds was above background concentrations but below toxic concentrations. In contrast, selenium was present in a killdeer (Charadrium vociferus) liver sample at potentially toxic con

Occurrence of anthropogenic organic compounds in ground water and finished water of community water systems in Eagle and Spanish Springs Valleys, Nevada, 2002-2004

USGS Publications Warehouse

Rosen, Michael R.; Shaefer, Donald H.; Toccalino, Patricia A.; Delzer, Gregory C.

2006-01-01

As a part of the U.S. Geological Survey's National Water-Quality Assessment Program, an effort to characterize the quality of major rivers and aquifers used as a source of supply to some of the largest community water systems (CWSs) in the United States has been initiated. These studies, termed Source Water-Quality Assessments (SWQAs), consist of two sampling phases. Phase 1 was designed to determine the frequency of detection and concentrations of about 260 volatile organic compounds (VOCs), pesticides and pesticide degradates, and other anthropogenic organic compounds in source water of 15 CWS wells in each study. Phase 2 monitors concentrations in the source water and also the associated finished water of CWSs for compounds most frequently detected during phase 1. One SWQA was completed in the Nevada Basin and Range area in Nevada. Ten CWS wells in Eagle Valley and five CWS wells in Spanish Springs Valley were sampled. For phase 2, two wells were resampled in Eagle Valley. Samples were collected during 2002-2004 for both phases. Water use in Eagle Valley is primarily for domestic purposes and is supplied through CWSs. Ground-water sources provide about 55 percent of the public-water supply, and surface-water sources supply about 45 percent. Lesser amounts of water are provided by domestic wells. Very little water is used for agriculture or manufacturing. Spanish Springs Valley has water-use characteristics similar to those in Eagle Valley, although there is more agricultural water use in Spanish Springs Valley than in Eagle Valley. Maximum contaminant concentrations were compared to two human-health benchmarks, if available, to describe the water-quality data in a human-health context for these findings. Measured concentrations of regulated contaminants were compared to U.S. Environmental Protection Agency and Nevada Maximum Contaminant Level (MCL) values. Measured concentrations of unregulated contaminants were compared to Health-Based Screening Levels, which are not regulatory standards and are not legally enforceable values. All of the contaminants detected in this study were found at concentrations less than available human-health benchmarks. In the source waters sampled in phase 1, 10 contaminants of the approximately 260 measured were detected in samples collected from Eagle Valley, and 4 contaminants were detected in samples from Spanish Springs Valley. The most frequently detected compounds in the Eagle Valley source water were chloroform (a disinfection by-product), which was detected in samples from four wells, and deethylatrazine (a degradation product of the herbicide atrazine), which was detected in samples from three wells. Each of the four contaminants detected in the Spanish Springs Valley source waters was detected in samples from one well. The detection frequencies of VOCs and pesticides in samples from the SWQA wells were similar to those in samples from both shallow and deep monitoring wells in Carson City, Reno, and Spanish Springs. This indicates that the SWQA sampling is representative of the organic chemical compounds likely to be detected in the aquifers sampled. However, more organic compounds were detected at low frequencies and concentrations in samples from the monitoring wells than in samples from SWQA wells. Three contaminants were detected in one finished-water sample collected from Eagle Valley. Comparison of SWQA results in the Nevada Basin and Range Study Unit to results of an SWQA in the larger urban area of Salt Lake City showed that fewer anthropogenic compounds were detected in Eagle and Spanish Springs Valleys and generally at lower concentrations than in the Salt Lake City study.

Mercury, cadmium, lead, and selenium in three waterbird species nesting in Galveston Bay, Texas, USA

USGS Publications Warehouse

King, K.A.; Cromartie, E.

1986-01-01

Heavy metal and selenium concentrations were determined in Olivaceous Cormorants (Phalacrocorax olivaceus ), Laughing gulls (Larus atricilla ), and Black Skimmers (Rynchops niger ) nesting in Galveston Bay, Texas, during 1980-81. Lead was detected at low levels in a small proportion of the liver samples. Mercury was present in all livers sampled, the highest levels being found in cormorants (7.8 ppm) and skimmers (16 ppm). Concentrations were considerably lower than those reported in birds from mercury-contaminated lakes in northern United States and Canada. Cadmium and selenium were detected in 93 and 95% of the kidneys. Cadmium was highest in gulls and skimmers with a maximum value of 16 ppm. Selenium levels were similar among species except for higher concentrations in gulls collected in 1981.

Characterization of the quality of water, bed sediment, and fish in Mittry Lake, Arizona, 2014–15

USGS Publications Warehouse

Hermosillo, Edyth; Coes, Alissa L.

2017-03-01

Water, bed-sediment, and fish sampling was conducted in Mittry Lake, Arizona, in 2014–15 to establish current water-quality conditions of the lake. The parameters of temperature, dissolved-oxygen concentration, specific conductance, and alkalinity were measured in the field. Water samples were collected and analyzed for dissolved major ions, dissolved trace elements, dissolved nutrients, dissolved organic carbon, dissolved pesticides, bacteria, and suspended-sediment concentrations. Bed-sediment and fish samples were analyzed for trace elements, halogenated compounds, total mercury, and methylmercury.U.S. Environmental Protection Agency secondary maximum contaminant levels in drinking water were exceeded for sulfate, chloride, and manganese in the water samples. Trace-element concentrations were relatively similar between the inlet, middle, and outlet locations. Concentrations for nutrients in all water samples were below the Arizona Department of Environmental Quality’s water-quality standards for aquatic and wildlife uses, and all bacteria levels were below the Arizona Department of Environmental Quality’s recommended recreational water-quality criteria. Three out of 81 pesticides were detected in the water samples.Trace-element concentrations in bed sediment were relatively consistent between the inlet, middle, and outlet locations. Lead, manganese, nickel, and zinc concentrations, however, decreased from the inlet to outlet locations. Concentrations for lead, nickel, and zinc in some bed-sediment samples exceeded consensus-based sediment-quality guidelines probable effect concentrations. Eleven out of 61 halogenated compounds were detected in bed sediment at the inlet location, whereas three were detected at the middle location, and five were detected at the outlet location. No methylmercury was detected in bed sediment. Total mercury was detected in bed sediment at concentrations below the consensus-based sediment-quality guidelines probable effect concentration.Sixteen trace elements were detected in at least one of the fish-tissue samples, and trace-element concentrations were relatively consistent between the three fish-tissue samples. Seven halogenated compounds were detected in at least one of the whole-body fish samples; four to five compounds were detected in each fish. One fish-tissue sample exceeded the U.S. Environmental Protection Agency human health consumption criteria for methylmercury.

Water-quality assessment of the Trinity River basin, Texas : ground-water quality of the Trinity, Carrizo-Wilcox, and Gulf Coast aquifers, February-August 1994

USGS Publications Warehouse

Reutter, David C.; Dunn, David D.

2000-01-01

Ground-water samples were collected from wells in the outcrops of the Trinity, Carrizo-Wilcox, and Gulf Coast aquifers during February-August 1994 to determine the quality of ground water in the three major aquifers in the Trinity River Basin study unit, Texas. These samples were collected and analyzed for selected properties, nutrients, major inorganic constituents, trace elements, pesticides, dissolved organic carbon, total phenols, methylene blue active substances, and volatile organic compounds as part of the U.S. Geological Survey National Water-Quality Assessment Program. Quality-control practices included the collection and analysis of blank, duplicate, and spiked samples. Samples were collected from 12 shallow wells (150 feet or less) and from 12 deep wells (greater than 150 feet) in the Trinity aquifer, 11 shallow wells and 12 deep wells in the Carrizo-Wilcox aquifer, and 14 shallow wells and 10 deep wells in the Gulf Coast aquifer. The three aquifers had similar water chemistries-calcium was the dominant cation and bicarbonate the dominant anion. Statistical tests relating well depths to concentrations of nutrients and major inorganic constituents indicated correlations between well depth and concentrations of ammonia nitrogen, nitrite plus nitrate nitrogen, bicarbonate, sodium, and dissolved solids in the Carrizo-Wilcox aquifer and between well depth and concentrations of sulfate in the Gulf Coast aquifer. The tests indicated no significant correlations for the Trinity aquifer. Concentrations of dissolved solids were larger than the secondary maximum contaminant level of 500 milligrams per liter established for drinking water by the U.S. Environmental Protection Agency in 12 wells in the Trinity aquifer, 4 wells in the Carrizo-Wilcox aquifer, and 6 wells in the Gulf Coast aquifer. Iron concentrations were larger than the secondary maximum contaminant level of 300 micrograms per liter in at least 3 samples from each aquifer, and manganese concentrations were larger than the secondary maximum contaminant level of 50 micrograms per liter in at least 2 samples from each aquifer. The pesticides atrazine, deethylatrazine, and pp'-DDE were detected in at least one sample from each aquifer. Diazinon was detected in 11 Trinity aquifer samples and 4 Carrizo-Wilcox aquifer samples. Each aquifer had one detection of a volatile organic compound-benzene in the Trinity aquifer, trichlorofluoromethane in the Carrizo-Wilcox aquifer, and trichloromethane in the Gulf Coast aquifer.

Distribution and Properties of a Potassium-dependent Asparaginase Isolated from Developing Seeds of Pisum sativum and Other Plants 1

PubMed Central

Sodek, Ladaslav; Lea, Peter J.; Miflin, Benjamin J.

1980-01-01

Asparaginase (EC 3.5.1.1) was isolated from the developing seed of Pisum sativum. The enzyme is dependent upon the presence of K+ for activity, although Na+ and Rb+ may substitute to a lesser extent. Maximum activity was obtained at K+ concentrations above 20 millimolar. Potassium ions protected the enzyme against heat denaturation. The enzyme has a molecular weight of 68,300. Asparaginase activity developed initially in the testa, with maximum activity (3.6 micromoles per hour per seed) being present 13 days after flowering. Maximum activity (1.2 micromoles per hour per seed) did not develop in the cotyledon until 21 days after flowering. Glutamine synthetase and glutamate dehydrogenase were also present in the testae and cotyledons but maximum activity developed later than that of asparaginase. Potassium-dependent asparaginase activity was also detected in the developing seeds of Vicia faba, Phaseolus multiflorus, Zea mays, Hordeum vulgare, and two Lupinus varieties. No stimulation of activity was detected with the enzyme isolated from Lupinus polyphyllus, which has previously been shown to contain a K+-independent enzyme. PMID:16661136

Matrix-Matching as an Improvement Strategy for the Detection of Pesticide Residues.

PubMed

Giacinti, Géraldine; Raynaud, Christine; Capblancq, Sophie; Simon, Valérie

2016-05-01

More than 90% of the pesticides residues in apples are located in the peel. We developed a gas chromatography/ion trap tandem mass spectrometry method for investigating all detectable residues in the peel of 3 apple varieties. Sample preparation is based on the use of the Quick Easy Cheap Effective Rugged and Safe method on the whole fruit, the flesh, and the peel. Pesticide residues were quantified with solvent-matched and matrix-matched standards, by spiking apple sample extracts. Matrix effects dependent on the type of extract (fruit, flesh, or peel) and the apple variety were detected. The best data processing methods involved normalizing matrix effect rates by matrix-matched internal/external calibration. Boscalid, captan, chlorpyrifos, fludioxonil, and pyraclostrobin were the most frequently detected pesticides. However, their concentrations in the whole fruit were below European maximum residue levels. Despite negative matrix effects, the residues in peel were detected at concentrations up to 10 times higher than those in whole fruits. Consequently, other pesticide residues present at concentrations below the limit of quantification in the whole fruit were detected in the peel. © 2016 Institute of Food Technologists®

Characterization of stormwater discharges from Las Flores Industrial Park, Rio Grande, Puerto Rico, 1998-99

USGS Publications Warehouse

Rodriguez, Jose M.

2000-01-01

Stormwater discharges from Las Flores Industrial Park, Rio Grande, Puerto Rico, were characterized from June 1998 to July 1999 by measuring the flow rate at two outfalls, delineating the drainage areas for each outfall, and calculating the volume of the stormwater discharges. Stormwater-discharge samples were collected and analyzed to determine the quality of the discharges. Constituent loads and loads per area were estimated for each drainage area. The studied drainage subareas covered approximately 46 percent of the total area of the Las Flores Industrial Park. Industrial groups represented in the study areas include manufacturers of textile, electronics, paper, fabricated metal, plastic, and chemical products. The concentrations of oil and grease (1 to 6 milligrams per liter), biochemical oxygen demand (4.7 to 16 milligrams per liter), total organic carbon (5.8 to 36 milligrams per liter), total suspended solids (28 to 100 milligrams per liter), and total phosphorous (0.11 to 0.78 milligrams per liter) from all the samples collected were less than the U.S. Environmental Protection Agency stormwater benchmark concentrations. Concentrations of chemical oxygen demand (15.8 to 157 milligrams per liter) and nitrate and nitrite (0.06 to 1.75 milligrams per liter) exceeded benchmark concentrations at one of the studied drainage areas. Total Kjeldahl nitrogen concentrations (1.00 to 3.20 milligrams per liter) exceeded the benchmark concentrations at the two studied drainage areas. Maximum concentrations for oil and grease, biochemical oxygen demand, chemical oxygen demand, total organic carbon, total Kjeldahl nitrogen, nitrate plus nitrite, and total phosphorous were detected in an area where electronics, plastics, and chemical products are currently manufactured. The maximum concentration of total suspended solids was detected at an area where textile, paper, plastic, chemical, and fabricated metal products are manufactured.

Groundwater-quality characteristics for the Wyoming Groundwater-Quality Monitoring Network, November 2009 through September 2012

USGS Publications Warehouse

Boughton, Gregory K.

2014-01-01

Groundwater samples were collected from 146 shallow (less than or equal to 500 feet deep) wells for the Wyoming Groundwater-Quality Monitoring Network, from November 2009 through September 2012. Groundwater samples were analyzed for physical characteristics, major ions and dissolved solids, trace elements, nutrients and dissolved organic carbon, uranium, stable isotopes of hydrogen and oxygen, volatile organic compounds, and coliform bacteria. Selected samples also were analyzed for gross alpha radioactivity, gross beta radioactivity, radon, tritium, gasoline range organics, diesel range organics, dissolved hydrocarbon gases (methane, ethene, and ethane), and wastewater compounds. Water-quality measurements and concentrations in some samples exceeded numerous U.S. Environmental Protection Agency (EPA) drinking water standards. Physical characteristics and constituents that exceeded EPA Maximum Contaminant Levels (MCLs) in some samples were arsenic, selenium, nitrite, nitrate, gross alpha activity, and uranium. Total coliforms and Escherichia coli in some samples exceeded EPA Maximum Contaminant Level Goals. Measurements of pH and turbidity and concentrations of chloride, sulfate, fluoride, dissolved solids, aluminum, iron, and manganese exceeded EPA Secondary Maximum Contaminant Levels in some samples. Radon concentrations in some samples exceeded the alternative MCL proposed by the EPA. Molybdenum and boron concentrations in some samples exceeded EPA Health Advisory Levels. Water-quality measurements and concentrations also exceeded numerous Wyoming Department of Environmental Quality (WDEQ) groundwater standards. Physical characteristics and constituents that exceeded WDEQ Class I domestic groundwater standards in some samples were measurements of pH and concentrations of chloride, sulfate, dissolved solids, iron, manganese, boron, selenium, nitrite, and nitrate. Measurements of pH and concentrations of chloride, sulfate, dissolved solids, aluminum, iron, manganese, boron, and selenium exceeded WDEQ Class II agriculture groundwater standards in some samples. Measurements of pH and concentrations of sulfate, dissolved solids, aluminum, boron, and selenium exceeded WDEQ Class III livestock groundwater standards in some samples. The concentrations of dissolved solids in two samples exceeded the WDEQ Class IV industry groundwater standard. Measurements of pH and concentrations of dissolved solids, aluminum, iron, manganese, and selenium exceeded WDEQ Class special (A) fish and aquatic life groundwater standards in some samples. Stable isotopes of hydrogen and oxygen measured in water samples were compared to the Global Meteoric Water Line and Local Meteoric Water Lines. Results indicated that recharge to all of the wells was derived from precipitation and that the water has undergone some fractionation, possibly because of evaporation. Concentrations of organic compounds did not exceed any State or Federal water-quality standards. Few volatile organic compounds were detected in samples, whereas gasoline range organics, diesel range organics, and methane were detected most frequently. Concentrations of wastewater compounds did not exceed any State or Federal water-quality standards. The compounds N,N-diethyl-meta-toluamide (DEET), benzophenone, and phenanthrene were detected most frequently. Bacteria samples were collected, processed, incubated, and enumerated in the field or at the U.S. Geological Survey Wyoming-Montana Water Science Center. Total coliforms and Escherichia coli were detected in some samples.

Water-quality assessment of the Ozark Plateaus study unit, Arkansas, Kansas, Missouri, and Oklahoma- summary of information on pesticides, 1970-90

USGS Publications Warehouse

Bell, Richard W.; Joseph, Robert L.; Freiwald, David A.

1996-01-01

Historical pesticide data from 1970-90 were compiled for 140 surface-water, 92 ground-water, 55 streambed-sediment, and 120 biological-tissue sampling sites within the Ozark Plateaus National Water-Quality Assessment Program study unit. Surface-water, bed-sediment, and biological-tissue sites have drainage basins predominantly in the Springfield and Salem Plateaus; ground-water sites are predominantly located in the Osage Plains and Mississippi Alluvial Plain. Many sites were sampled only once or twice during this period. A large percentage of the samples were collected in the mid-1970's and early 1980's for surface water, 1990 for ground water, the late 1980's for surface water, 1990 for ground water, the late 1980's for bed sediment, and the early 1980's for biological tissue. Pesticide use was approximately 4.2 million pounds per year of active ingredients from 1982-85 in the study unit and was generally greatest in the Springfield and Salem Plateaus pasturelands and in the Osage Plains and Mississippi Alluvial Plain cropland areas. The most frequently applied pesticide in the study unit was 2,4-D. Alachlor was the second most applied pesticide. Corn, pasture, rice, sorghum, and soybeans received approximately 90 percent of the pesticides applied within the study unit. The highest pesticide application rate per acre occurred on these crops in the Osage Plains and Mississippi Alluvial Plain. Pastureland was the predominant crop type in 50 of the 94 counties in the study unit. Toxaphene, the pesticide having the most number of detections in surface water, was found in 17 of 866 samples from 5 of 112 sites. Concentrations ranged from 0.1 to 6.0 micrograms per liter. Six other pesticides or pesticide metabolites were detected in 12 or more surface-water samples: DDE, dieldrin, DDT, aldrin, 2,4-D, and lindane. The maximum concentration for these pesticides was less than 1.0 micrograms per liter. Atrazine, the pesticide having the most number of detections in ground water, was found in 15 of 95 samples from 15 of 79 wells with concentrations ranging from 0.1 to 8.2 micrograms per liter. Metolachlor, alachlor, and prometon were detected more than once with maximum concentrations less than 1.0 micrograms per liter, except for prometon (2.4 micrograms per liter). Chlordane was the pesticide having the most number of detections in bed sediment and biological tissue. Chlordane was detected in 12 of 73 samples from 10 of 45 bed-sediment sites with concentrations ranging from 2.0 to 240 micrograms per kilogram. In biological tissue, chlordane was found in 93 of 151 samples from 39 of 53 sites with concentrations ranging from 0.009 to 8.6 milligrams per kilogram. Other pesticides or pesticide metabolites detected more than once in bed sediment include DDT, DDD, p,p'-DDE, DDE, and hexachlorobenzene and in biological tissue include DDT, p,p'-DDE, and hexachlorobenzene. Quality criteria or standards have been established for 15 of the pesticides detected in the study unit. For surface-water samples, the drinking water maximum contaminant level for alachlor was exceeded in one sample from one site in 1982. For ground-water samples, the drinking water maximum contaminant level for atrazine was exceeded in four samples from four wells in 1990. For biological-tissue samples collected during the years 1982-89, the fish tissue action levels for chlordane (19 sites; 26 samples), heptachlor epoxide (3 sites; 3 samples), p,p'-DDE (2 sites; 2 samples), dieldrin (2 sites, 2 samples), and mirex (1 site; 1 sample) were exceeded. For bed-sediment samples, quality criteria or standards were not exceeded for any pesticide. Pesticides do not pose any widespread or persistent problems in the study unit, based on the limited number of samples that exceeded quality criteria and standards.

Nanoscale volume confinement and fluorescence enhancement with double nanohole aperture

PubMed Central

Regmi, Raju; Al Balushi, Ahmed A.; Rigneault, Hervé; Gordon, Reuven; Wenger, Jérôme

2015-01-01

Diffraction ultimately limits the fluorescence collected from a single molecule, and sets an upper limit to the maximum concentration to isolate a single molecule in the detection volume. To overcome these limitations, we introduce here the use of a double nanohole structure with 25 nm gap, and report enhanced detection of single fluorescent molecules in concentrated solutions exceeding 20 micromolar. The nanometer gap concentrates the light into an apex volume down to 70 zeptoliter (10−21 L), 7000-fold below the diffraction-limited confocal volume. Using fluorescence correlation spectroscopy and time-correlated photon counting, we measure fluorescence enhancement up to 100-fold, together with local density of optical states (LDOS) enhancement of 30-fold. The distinctive features of double nanoholes combining high local field enhancement, efficient background screening and relative nanofabrication simplicity offer new strategies for real time investigation of biochemical events with single molecule resolution at high concentrations. PMID:26511149

Increased breath nitrous oxide after ingesting nitrate in patients with atrophic gastritis and partial gastrectomy.

PubMed

Mitsui, Takahiro; Kondo, Takaharu

2004-07-01

Toxic nitrite and N-nitroso compounds due to gastric bacterial growth are often detected in the stomach of patients with atrophic gastritis and partial gastrectomy. The aim of this study is to investigate whether breath N2O, a major metabolite of denitrification, detected after ingestion of nitrate is associated with atrophic gastritis and partial gastrectomy. Nine young, 16 normal older, nine atrophic gastritis and six partial gastrectomy subjects ingested 100 g lettuce, equal to 130 mg nitrate, and breath N2O was measured at 15-min intervals for 5 h. N2O was analyzed using an infrared-photoacoustic analyzer, and atrophic gastritis was diagnosed by pepsinogen test. The mean breath N2O concentrations were higher in the following order at all times: partial gastrectomy>atrophic gastritis>normal>young. The maximum N2O concentrations in the patients with partial gastrectomy and atrophic gastritis were 1655 +/- 296 and 1350 +/- 200 (mean +/- S.E.) ppb, respectively, which were higher than that of the normal subjects, 827 +/- 91 ppb (P < 0.05). The maximum N2O concentration in young people was 527 +/- 86 ppb, which was lower than that of the normal older people (P < 0.051). These higher N2O concentrations in gastric patients reflect bacterial growth in the stomach due to the reduction of gastric acid. Copyright 2004 Elsevier B.V.

Levels of organophosphorus pesticides in medicinal plants commonly consumed in Iran

PubMed Central

2012-01-01

The frequent occurrence of pesticide residues in herbal materials was indicated by previous studies. In this study, the concentration of some of the organophosphorus pesticides including parathion, malathion, diazinon and pirimiphos methyl in different kinds of medicinal plants were determined. The samples were collected randomly from ten local markets of different areas of Iran. At the detection limit of 0.5 ng g-1, parathion and pirimiphos methyl were not detected in any of the samples. Some amounts of malathion and diazinon were found in Zataria, Matricaria chamomile, Spearmint and Cumin Seed samples while, the concentrations of target organophosphorus pesticides in Borage samples were below the detection limits of the methods which could be a result of intensive transformation of organophosphorus pesticides by Borage. In addition the organophosphorus pesticides were detected in all of the samples below the maximum residue levels (MRLs) proposed by the international organizations. PMID:23351610

Pesticides in surface water in the lower Illinois River basin, 1996-98

USGS Publications Warehouse

King, Robin B.

2003-01-01

Surface-water quality samples were collected from April 1996 to September 1998 from eight locations in the Lower Illinois River Basin, a study unit of the U.S. Geological Survey?s National Water-Quality Assessment program. The study area is approximately 15,600 square miles and encompasses most of central and western Illinois. The dominant land use is agricultural and most land is used for the production of corn and soybeans. About 6.9 million acres of corn and soybeans are planted annually in the lower Illinois River Basin. Conservation tillage, defined as mulch-till and no-till, is used on about 40 percent of the cropland in the study area, similar to the statewide average. Nearly 90 percent of the samples for pesticide analyses were collected at four sites: the Illinois River at Ottawa, the Illinois River at Valley City, the La Moine River at Colmar, and the Sangamon River at Monticello. Two hundred fifty-eight samples were collected and analyzed for various herbicides, insecticides, and herbicide transformation products (also referred to as degradates). Thirty-one pesticides were detected at concentrations above their respective method detection limit: 23 herbicides and 8 insecticides. An additional set of 34 samples was collected in the summer of 1998 for the analysis of herbicide transformation products. Nine herbicide transformation products were detected, all belonging to the chloroacetanilide or the triazine chemical class. Two herbicides, atrazine and cyanazine, exceeded the associated human health drinking-water criteria and the aquatic health-criteria. Atrazine was detected in all samples. Sixty percent of the samples (48 of 80) collected in the months of May and June had atrazine concentrations that exceeded the clean drinking- water standard of 3 micrograms per liter (mg/L). The average atrazine concentration in the May to June samples was about 7.0 mg/L. The maximum atrazine concentrations were 110 mg/L in the La Moine River at Colmar and 32 mg/L in the Sangamon River at Monticello. The maximum atrazine concentration in the lower Illinois River was 20 mg/L, measured at Valley City, although most of the relatively elevated concentrations in the Illinois River sites were in the range from 5 to 8 mg/L. The concentrations of the herbicide cyanazine exceeded the health advisory guideline of 1 mg/L in about 19 percent (15 of 80) of the May to June samples. The pesticides chlorpyrifos, diazinon, metolachlor, and 2,4-D exceeded aquatic health guidelines at various times from May to August. Three dominant factors that affect the presence of pesticides in streams are identified: the pesticide usage, the time-of-year (or season), and the flow condition. The pesticides with the highest usage--atrazine, metolachlor, cyanazine, and acetochlor--generally were the pesticides detected most frequently and at the highest concentrations. Notable exceptions to this general observation are alachlor and simazine, which did not have high usage but were detected frequently. The elevated pesticide concentrations were most affected by seasonality--most of these elevated concentrations were observed across all flow conditions during May to June. Flow conditions also affect pesticide concentrations, but not as much as seasonality. The maximum pesticide loads were observed between March and July on the Illinois River. The net contribution of pesticides applied in the study area to net increases in load indicates that only about 1-2 percent of the pesticides applied exit the basin through the Illinois River at Valley City. The chloroacetanilide-class transformation products observed in samples collected in summer 1998 persistently contained elevated concentrations relative to the associated parent pesticide compound at all locations and for all streamflow conditions. The concentration of the transformation product metolachlor ethane sulfonic acid (ESA) usually was about 10 times higher than the parent compound in the mainstem of the lower

First annual register of allergenic pollen in Talca, Chile.

PubMed

Mardones, P; Grau, M; Araya, J; Córdova, A; Pereira, I; Peñailillo, P; Silva, R; Moraga, A; Aguilera-Insunza, R; Yepes-Nuñez, J J; Palomo, I

2013-01-01

There are no data on atmospheric pollen in Talca. In the present work, our aim is to describe the amount of pollen grain in the atmosphere of the city of Talca likely to cause pollinosis of its inhabitants. A volumetric Hirst sampler (Burkard seven-day recording device) was used to study pollen levels. It was placed in the centre of Talca from May 2007 to April 2008. The highest airborne presence of pollen, as measured in weekly averages, was Platanus acerifolia with a maximum weekly daily average of 203 grains/m³ registered during September and October. The second highest was Acer pseudoplatanus with a maximum weekly daily average of 116 grains/m³. Populus spp. had a maximum weekly daily average 103 grains/m³. Olea europaea reached 19 grains/m³ in November. Grasses presented high levels of pollen counts with a maximum weekly daily average of 27 grains/m³ from the end of August until the end of January. Pollens of Plantago spp. Rumex acetosella and Chenopodium spp. had a similar distribution and were present from October to April with maximum weekly daily average of 7 grains/m³, 7 grains/m³ and 3 grains/m³ respectively. Significant concentrations of Ambrosia artemisiifolia were detected from February until April. The population of Talca was exposed to high concentrations of allergenic pollen, such as P. acerifolia, A. pseudoplatanus, and grasses in the months of August through November. The detection of O. europaea and A. artemisiifolia is important as these are emergent pollens in the city of Talca. Aerobiological monitoring will provide the community with reliable information about the level of allergenic pollens, improving treatment and quality of life of patients with respiratory allergy. Copyright © 2011 SEICAP. Published by Elsevier Espana. All rights reserved.

Distribution of lead in selected organs and its effect on reproduction parameters of pheasants (Phasianus colchicus) after an experimental per oral administration.

PubMed

Gasparik, Jozef; Venglarcik, Jozef; Slamecka, Jaroslav; Kropil, Rudolf; Smehyl, Peter; Kopecky, Jan

2012-01-01

Lead poisoning has been reported in almost every country on earth. In this study the effect of experimental lead pellet intake (2-6 pellets per week [groups B2, B4, B6] and ad libitum [BAD] accessibility for 10 weeks) on its distribution in liver, kidney, pectoral muscle, ovary, eggs and the effect of selected reproductive parameters (egg weight, fertilization, hatchability) was analyzed in breeding pheasants. Lead pellets were force fed to the digestive tract (struma, ingluvies) and the ingestion was controlled. Concentration of lead was detected using the atomic absorption spectrophotometry. Analysis of the lead concentration in liver showed a significantly higher concentration in all group after the lead pellets intake. The increase of the lead concentration was dose-dependent and the concentration detected in group BAD was similar as in group B2. Very similar tendencies were detected for the lead concentration in kidney. The accumulation of lead in pectoral muscle was lower, in comparison with liver and kidney. Compared to lead concentration detected in ovary of the control group a significant increase was detected in all experimental groups, reaching the maximum in the group B6. Similar significant increase of lead concentration was detected in eggs. The average weight of eggs was 32.01 ± 2.71 g in the control group and lower in all experimental groups, but this decrease was significant only in the group B6. The fertilization rate was the highest in the control group and a dose-dependent decrease was detected with the lowest value in the group B6. For egg hatching ratio a significant decrease was detected in groups B4 and B6. Results of this study clearly describe accumulation of lead in the body and a its negative effect on the reproductive parameters. In the ad libitum experimental group the most similar results were found as in group B2, suggesting a rate of "natural" lead pellet intake.

Ground-water monitoring plan, water quality, and variability of agricultural chemicals in the Missouri River alluvial aquifer near the City of Independence, Missouri, well field, 1998-2000

USGS Publications Warehouse

Kelly, Brian P.

2002-01-01

A detailed ground-water sampling plan was developed and executed for 64 monitoring wells in the city of Independence well field to characterize ground-water quality in the 10-year zone of contribution. Samples were collected from monitoring wells, combined Independence well field pumpage, and the Missouri River at St. Joseph, Missouri, from 1998 through 2000. In 328 ground-water samples from the 64 monitoring wells and combined well field pumpage samples, specific conductance values ranged from 511 to 1,690 microsiemens per centimeter at 25 degrees Celsius, pH values ranged from 6.4 to 7.7, water temperature ranged from 11.3 to 23.6 degrees Celsius, and dissolved oxygen concentrations ranged from 0 to 3.3 milligrams per liter. In 12 samples from the combined well field pumpage samples, specific conductance values ranged from 558 to 856 microsiemens per centimeter at 25 degrees Celsius, pH values ranged from 6.9 to 7.7, water temperature ranged from 5.8 to 22.9 degrees Celsius, and dissolved oxygen concentrations ranged from 0 to 2.4 milligrams per liter. In 45 Missouri River samples, specific conductance values ranged from 531 to 830 microsiemens per centimeter at 25 degrees Celsius, pH ranged from 7.2 to 8.7, water temperature ranged from 0 to 30 degrees Celsius, and dissolved oxygen concentrations ranged from 5.0 to 17.6 milligrams per liter. The secondary maximum contaminant level for sulfate in drinking water was exceeded once in samples from two monitoring wells, the maximum contaminant level (MCL) for antimony was exceeded once in a sample from one monitoring well, and the MCL for barium was exceeded once in a sample from one monitoring well. The MCL for iron was exceeded in samples from all monitoring wells except two. The MCL for manganese was exceeded in all samples from monitoring wells and combined well field pumpage. Enzyme linked immunoassay methods indicate total benzene, toluene, ethyl benzene, and xylene (BTEX) was detected in samples from five wells. The highest total BTEX concentration was less than the MCL of toluene, ethyl benzene, or xylene but greater than the MCL for benzene. Total BTEX was not detected in samples from any well more than once. Atrazine was detected in samples from nine wells, and exceeded the MCL once in a sample from one well. Alachlor was detected in samples from 22 wells but the MCL was never exceeded in any sample. Samples from five wells analyzed for a large number of organic compounds indicate concentrations of volatile organic compounds did not exceed the MCL for drinking water. No semi-volatile organic compounds were detected; dieldrin was detected in one well sample, and no other pesticides, herbicides, polychlorinated biphenyls, or polychlorinated napthalenes were detected. Dissolved ammonia, dissolved nitrite plus nitrate, dissolved orthophosphorus, alachlor, and atrazine analyses were used to determine the spatial and temporal variability of agricultural chemicals in ground water. Detection frequencies for dissolved ammonia increased with well depth, decreased with depth for dissolved nitrite plus nitrate, and remained relatively constant with depth for dissolved orthophosphorus. Maximum concentrations of dissolved ammonia, dissolved nitrite plus nitrate, and dissolved orthophosphorus were largest in the shallowest wells and decreased with depth, which may indicate the land surface as the source. However, median concentrations increased with depth for dissolved ammonia, were less than the detection limit for dissolved nitrite plus nitrate, and decreased with depth for dissolved orthophosphorus. This pattern does not indicate a well-defined single source for these constituents. Dissolved orthophosphorus median concentrations were similar, but decreased slightly with depth, and may indicate the land surface as the source. Seasonal variability of dissolved ammonia, dissolved nitrite plus nitrate, a

Occurrence of veterinary antibiotics and progesterone in broiler manure and agricultural soil in Malaysia.

PubMed

Ho, Yu Bin; Zakaria, Mohamad Pauzi; Latif, Puziah Abdul; Saari, Nazamid

2014-08-01

Repeated applications of animal manure as fertilizer are normal agricultural practices that may release veterinary antibiotics and hormones into the environment from treated animals. Broiler manure samples and their respective manure-amended agricultural soil samples were collected in selected locations in the states of Selangor, Negeri Sembilan and Melaka in Malaysia to identify and quantify veterinary antibiotic and hormone residues in the environment. The samples were analyzed using ultrasonic extraction followed by solid phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). The broiler manure samples were found to be contaminated with at least six target analytes, namely, doxycycline, enrofloxacin, flumequine, norfloxacin, trimethoprim and tylosin. These analytes were detected in broiler manure samples with maximum concentrations reaching up to 78,516 μg kg(-1) dry weight (DW) (doxycycline). For manure-amended agricultural soil samples, doxycycline and enrofloxacin residues were detected in every soil sample. The maximum concentration of antibiotic detected in soil was 1331 μg kg(-1) DW (flumequine). The occurrence of antibiotics and hormones in animal manure at high concentration poses a risk of contaminating agricultural soil via fertilization with animal manure. Some physico-chemical parameters such as pH, total organic carbon (TOC) and metal content played a considerable role in the fate of the target veterinary antibiotics and progesterone in the environment. It was suggested that these parameters can affect the adsorption of pharmaceuticals to solid environmental matrices. Copyright © 2014 Elsevier B.V. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

LaFreniere, L. M.

Carbon tetrachloride contamination in groundwater at Morrill, Kansas, was initially identified in 1985 during statewide testing of public water supply wells for volatile organic compounds (VOCs). High levels of nitrate were also present in the wells. The city of Morrill is located in Brown County in the northeastern corner of the state, about 7 mi east of Sabetha (Figure 1.1). The population of Morrill as of the 2010 Census was approximately 230 (down from 277 in 2000). All residents of Morrill now obtain their drinking water from the Sabetha municipal water system via a pipeline constructed in 1991. The findingsmore » of the April 2011 and October 2011 monitoring events at Morrill support the following conclusions: (1) Groundwater flow during the 2011 review period (as in prior years) was predominantly to the south, from the vicinity of the former CCC/USDA facility toward Terrapin Creek. Automatic water level monitoring data suggest that spring precipitation and recharge represent the predominant factors affecting the local groundwater level patterns. (2) No significant changes were observed in the concentration or distribution of carbon tetrachloride in groundwater during the spring and fall 2011 monitoring events versus the spring and fall 2010 monitoring events. In October 2011, a maximum carbon tetrachloride concentration of 49 {micro}g/L was identified in groundwater at well MW3S on the former CCC/USDA facility, with concentrations decreasing downgradient toward Terrapin Creek. (3) Since 2004, the accumulated results of 15 sampling events have demonstrated a significant decline in the maximum detected concentration of carbon tetrachloride in groundwater. In 1995, the contaminant was detected at the former CCC/USDA facility at 390 {micro}g/L, while the current maximum levels are < 50 {micro}g/L. The residual contaminant plume extending from the former CCC/USDA facility southward toward Terrapin Creek is well-defined and slowly declining in concentration naturally. (4) No carbon tetrachloride contamination was detected in 2011 in surface waters or shallow streambed sediments sampled at five locations along Terrapin Creek, downgradient from the former CCC/USDA facility. These results indicate that Terrapin Creek remains unaffected by the carbon tetrachloride plume. (5) Since 2007, the accumulated results of 10 monitoring events for surface water and sediment in Terrapin Creek have demonstrated no impact to the sediment and surface waters of the creek by carbon tetrachloride and no imminent risk for further degradation of the creek. (6) Terrapin Creek (tributary segment 308 to Walnut Creek) receives discharge from the Morrill wastewater treatment plant and several confined animal feeding operations regulated by the KDHE. The Walnut Creek watershed is designated by the KDHE as impaired by fecal coliform bacteria. Terrapin Creek is classified by the KDHE as not open to or accessible by the public for contact recreation and does not support the food procurement designated use (KDHE 2010b). (7) In July 2011, trace concentrations of carbon tetrachloride were detected in vegetation samples collected from trees at 2 of the 42 sampled locations south (downgradient) of the former CCC/USDA facility. (8) Sampling of indoor air in August 2010 to evaluate the potential for vapor intrusion into homes overlying and within 100 ft laterally of the identified carbon tetrachloride plume resulted in no detections of carbon tetrachloride. Low concentrations of chloroform, indicative of indoor air sources, were detected. Low radon levels were also detected. The results indicate no evidence of upward migration of vapors from the low-level carbon tetrachloride contamination in groundwater to indoor air.« less

Integration of Multiplexed Microfluidic Electrokinetic Concentrators with a Morpholino Microarray via Reversible Surface Bonding for Enhanced DNA Hybridization.

PubMed

Martins, Diogo; Wei, Xi; Levicky, Rastislav; Song, Yong-Ak

2016-04-05

We describe a microfluidic concentration device to accelerate the surface hybridization reaction between DNA and morpholinos (MOs) for enhanced detection. The microfluidic concentrator comprises a single polydimethylsiloxane (PDMS) microchannel onto which an ion-selective layer of conductive polymer poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) ( PSS) was directly printed and then reversibly surface bonded onto a morpholino microarray for hybridization. Using this electrokinetic trapping concentrator, we could achieve a maximum concentration factor of ∼800 for DNA and a limit of detection of 10 nM within 15 min. In terms of the detection speed, it enabled faster hybridization by around 10-fold when compared to conventional diffusion-based hybridization. A significant advantage of our approach is that the fabrication of the microfluidic concentrator is completely decoupled from the microarray; by eliminating the need to deposit an ion-selective layer on the microarray surface prior to device integration, interfacing between both modules, the PDMS chip for electrokinetic concentration and the substrate for DNA sensing are easier and applicable to any microarray platform. Furthermore, this fabrication strategy facilitates a multiplexing of concentrators. We have demonstrated the proof-of-concept for multiplexing by building a device with 5 parallel concentrators connected to a single inlet/outlet and applying it to parallel concentration and hybridization. Such device yielded similar concentration and hybridization efficiency compared to that of a single-channel device without adding any complexity to the fabrication and setup. These results demonstrate that our concentrator concept can be applied to the development of a highly multiplexed concentrator-enhanced microarray detection system for either genetic analysis or other diagnostic assays.

Stormflow chemistry in the Santa Ana River below Prado Dam and at the diversion downstream from Imperial Highway, southern California, 1995-98

USGS Publications Warehouse

Izbicki, John A.; Mendez, Gregory O.; Burton, Carmen A.

2000-01-01

The Santa Ana River drains about 2,670 square miles of the densely populated coastal area of southern California, near Los Angeles. Almost all the flow in the river, more than 200,000 acre-feet annually, is diverted into ponds where it infiltrates and recharges underlying aquifers. About 2 million people are dependent on these aquifers for water supply. Stormflow in the Santa Ana River is considered a source of 'high-quality' water suitable for use as a source of ground-water recharge. To test this assumption, stormflow samples were collected at two locations--below Prado Dam and at the diversion point downstream from Imperial Highway--for 12 winter storms between 1995 and 1998. Nitrate concentrations decreased during stormflow from a median concentration of 7.8 milligrams per liter in base flow to concentrations less than 1 milligram per liter in some large storms. Concentrations of chemically reduced forms of nitrogen (nitrite, ammonia, and organic nitrogen) increased during stormflow and are the predominant forms of nitrogen in large stormflows. Dissolved organic carbon (DOC) concentrations increased from a median concentration of 4.6 milligrams per liter in base flow to more than 20 milligrams per liter in some stormflows. Concentrations of DOC were especially high during the first storm of the rainy season, and large increases in DOC concentrations were measured even as a result of small early season storms that did not cause large increases in streamflow. DOC present during early season stormflow had less ultraviolet absorbance at 254 nanometers (UV254 ) per unit of carbon than did DOC from late season stormflows. DOC in water held in storage behind Prado Dam had the highest UV254 absorbance per unit of carbon. Maximum pesticide concentrations in stormflow did not exceed U.S. Environmental Protection Agency Maximum Contaminant Levels. Most pesticide concentrations were less than 1 microgram per liter and less than the detection limits obtained using standard drinking water analyses. Increases in concentrations of pesticides such as diazinon, malathion, and chlorpyrifos in stormflow result from runoff from urban areas downstream from Prado Dam. In general, large late season stormflows have the most pesticide detections of all stormflows sampled. Concentrations of methyl tert-butyl ether (MTBE), a gasoline additive, during base flow were as high as 0.9 microgram per liter and concentrations decreased during stormflow. Like pesticides, the concentrations did not exceed the U.S. Environmental Protection Agency Maximum Contaminant Levels for MTBE.

Spatiotemporal changes of CVOC concentrations in karst aquifers: analysis of three decades of data from Puerto Rico

PubMed Central

Yu, Xue; Ghasemizadeh, Reza; Padilla, Ingrid; Irizarry, Celys; Kaeli, David; Alshawabkeh, Akram

2014-01-01

We studied the spatial and temporal distribution patterns of Chlorinated Volatile Organic Compounds (CVOCs) in the karst aquifers in northern Puerto Rico (1982-2013). Seventeen CVOCs were widely detected across the study area, with the most detected and persistent contaminated CVOCs including trichloroethylene (TCE), tetrachloroethylene (PCE), carbon tetrachloride (CT), chloroform (TCM), and methylene chloride (DCM). Historically, 471 (76%) and 319 (52%) of the 615 sampling sites have CVOC concentrations above the detection limit and maximum contamination level (MCL), respectively. The spatiotemporal patterns of the CVOC concentrations showed two clusters of contaminated areas, one near the Superfund site “Upjohn” and another near “Vega Alta Public Supply Wells.” Despite a decreasing trend in concentrations, there is a general northward movement and spreading of contaminants even beyond the extent of known sources of the Superfund and landfill sites. Our analyses suggest that, besides the source conditions, karst characteristics (high heterogeneity, complex hydraulic and biochemical environment) are linked to the long-term spatiotemporal patterns of CVOCs in groundwater. PMID:25522355

Clean copy association of production diseases with motor activity-sensing devices and milk progesterone concentrations in dairy cows.

PubMed

Williams, J; Ntallaris, T; Routly, J E; Jones, D N; Cameron, J; Holman-Coates, A; Smith, R F; Humblot, P; Dobson, H

2018-05-31

We have previously established that the efficiency of identifying oestrus with activity-sensing devices can be compromised by common production diseases; the present study was undertaken to determine how these diseases may affect device readings. A total of 67 Holstein-Friesian cows, >20 days postpartum, were equipped with activity-sensing neck collars and pedometers, and simultaneous milk progesterone profiles were also monitored twice a week. The influences of common production stressors on maximum activity and progesterone values were analysed. Approximately 30% potential oestrus events (low progesterone value between two high values) remained unrecognised by both activity methods, and progesterone values in these animals were higher on the potential day of oestrus when both activity methods did not detect an event (0.043 ± 0.004 versus 0.029 ± 0.004 ng/mL; P = 0.03). Data from a subset of 45 cows (two events each) were subjected to mixed models and multiple regression modelling to investigate associations with production diseases. Cow motor activity was lower in lame cows. Maximum progesterone concentrations prior to oestrus increased as time postpartum and body condition score (BCS) increased. There were also fewer days of low progesterone prior to oestrus associated with increases in BCS and maximum progesterone concentrations prior to oestrus. In conclusion, lameness was associated with lower activity values, but this suppression was insufficient to account for lowered oestrus detection efficiency of either device. However, associations were identified between production diseases and progesterone profiles. Copyright © 2018. Published by Elsevier Inc.

Nationwide reconnaissance of contaminants of emerging ...

EPA Pesticide Factsheets

Mobile and persistent chemicals that are present in urban wastewater, such as pharmaceuticals, may survive on-site or municipal wastewater treatment and post-discharge environmental processes. These pharmaceuticals have the potential to reach surface and groundwaters, essential drinking-water sources. A joint, two-phase U.S. Geological Survey-U.S. Environmental Protection Agency study examined source and treated waters from 25 drinking-water treatment plants from across the United States. Treatment plants that had probable wastewater inputs to their source waters were selected to assess the prevalence of pharmaceuticals in such source waters, and to identify which pharmaceuticals persist through drinking-water treatment. All samples were analyzed for 24 pharmaceuticals in Phase I and for 118 in Phase II. In Phase I, 11 pharmaceuticals were detected in all source-water samples, with a maximum of nine pharmaceuticals detected in any one sample. The median number of pharmaceuticals for all 25 samples was five. Quantifiable pharmaceutical detections were fewer, with a maximum of five pharmaceuticals in any one sample and a median for all samples of two. In Phase II, 47 different pharmaceuticals were detected in all source-water samples, with a maximum of 41 pharmaceuticals detected in any one sample. The median number of pharmaceuticals for all 25 samples was eight. For 37 quantifiable pharmaceuticals in Phase II, median concentrations in source water were below 11

Effects of agricultural and residential land use on ground-water quality, Anoka Sand Plain Aquifer, east-central Minnesota

USGS Publications Warehouse

Anderson, H.W.

1993-01-01

Triazine herbicides were detected in 11 of 18 samples analyzed for pesticides. Concentrations of atrazine were less than the 3 (J-g/L maximum contaminant level set for atrazine by the Minnesota Department of Health and by the U.S. Environmental Protection Agency.

Occurrence of contaminants of emerging concern in mussels (Mytilus spp.) along the California coast and the influence of land use, storm water discharge, and treated wastewater effluent.

PubMed

Dodder, Nathan G; Maruya, Keith A; Lee Ferguson, P; Grace, Richard; Klosterhaus, Susan; La Guardia, Mark J; Lauenstein, Gunnar G; Ramirez, Juan

2014-04-30

Contaminants of emerging concern were measured in mussels collected along the California coast in 2009-2010. The seven classes were alkylphenols, pharmaceuticals and personal care products, polybrominated diphenyl ethers (PBDE), other flame retardants, current use pesticides, perfluorinated compounds (PFC), and single walled carbon nanotubes. At least one contaminant was detected at 67 of the 68 stations (98%), and 67 of the 167 analytes had at least one detect (40%). Alkylphenol, PBDE, and PFC concentrations increased with urbanization and proximity to storm water discharge; pesticides had higher concentrations at agricultural stations. These results suggest that certain compounds; for example, alkylphenols, lomefloxacin and PBDE, are appropriate for inclusion in future coastal bivalve monitoring efforts based on maximum concentrations >50 ng/g dry weight and detection frequencies >50%. Other compounds, for example PFC and hexabromocyclododecane (HBCD), may also be suggested for inclusion due to their >25% detection frequency and potential for biomagnification. Copyright © 2013 Elsevier Ltd. All rights reserved.

PHARMACOKINETIC PROPERTIES OF A SINGLE ADMINISTRATION OF ORAL GABAPENTIN IN THE GREAT HORNED OWL (BUBO VIRGINIANUS).

PubMed

Yaw, Taylor J; Zaffarano, Bianca A; Gall, Andrew; Olds, June E; Wulf, Larry; Papastavros, Efthimia; Coetzee, Johann F

2015-09-01

Gabapentin (1-[aminomethyl] cyclohexane acetic acid) is a γ-aminobutyric acid analogue that has been shown to be efficacious for neuropathic pain control in humans. Plasma gabapentin concentrations >2 μg/ml are considered effective in treating epilepsy in humans and are suggested to provide analgesia for neuropathic pain. This study investigated the pharmacokinetics of a single oral dose of gabapentin suspension (11 mg/kg) in great horned owls ( Bubo virginianus ). Plasma gabapentin concentrations were determined in six healthy birds for 48 hr using high-performance liquid chromatography with mass spectrometric detection. Plasma gabapentin concentrations were estimated by noncompartmental pharmacokinetic analysis. The harmonic mean (±SD) maximum concentration (Cmax), time to maximum concentration (Tmax), and elimination half-life (tv2λZ) for gabapentin (11 mg/kg) were 6.17±0.83 μg/ml, 51.43±5.66 min, and 264.60±69.35 min, respectively. In this study, plasma gabapentin concentrations were maintained above 2 μg/ml for 528 min (8.8 hr), suggesting that gabapentin administered orally every 8 hr may be appropriate in great horned owls.

Estuarine methylation of tin and its relationship to the microbial sulfur cycle

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gilmour, C.C.

This work describes the first quantitative measurement of tin methylation in nature. Central to this research was development of a technique for the determination of methyltin species in sediment with detection limits of about 1 pg per gm dry weight sediment. Methyltin concentrations measured in Chesapeake Bay sediments ranged from 0.005 to 8 ng per gm dry weight sediment, with monomethyltin the predominant species. Estuarine tin methylation occurred only in anoxic, sulfidic sediments and was microbially mediated. Sulfate-reducing bacteria were correlated with methyltin production in sediments, and capable of tin methylation in pure culture without sediment. Conversely, excess sulfide concentrationsmore » inhibited methylation. Sulfate reduction rates and reduced inorganic sulfur distribution between acid-volatile and non-volatile sulfides for Chesapeake sediments were also determined. Monomethyltin was the predominant product of stepwise inorganic tin methylation in sediments and bacterial cultures, with di- and trimethylated tins produced in lesser amounts. Methylation rates based on accumulation of all detectable methyltin species were quite low. Maximum concentrations of methyltins formed were quite low. Maximum concentrations of methyltins formed were 10 ng total methyltins per ml culture, or 4 ng per gm dry weight sediment. Trimethyltin, the most toxic product, was produced in the smallest quantities, never more than 50 pg per gm sediment.« less

A preliminary investigation on the distribution of cannabinoids in man.

PubMed

Gronewold, Antonia; Skopp, Gisela

2011-07-15

An LC/MS/MS procedure to determine THC along with its major metabolites 11-OH-THC, THC-COOH and its glucuronide as well as the cannabinoids CBD and CBN was applied to 5 post mortem cases to study their distribution into some less commonly studied matrices. Analytes were determined in fluids and tissue homogenates following protein precipitation and liquid-liquid extraction. Gall bladder fluid exhibited maximum concentrations of all analytes except THC, which was detectable in high concentrations in muscle tissue along with CBD. THC was also present in lung specimens, whereas its concentration in liver samples was low or not detectable at all. Liver und kidney specimens contained appreciable amounts of THC-COOglu. Findings from bile support extensive enterohepatic recirculation of the glucuronide. Muscle tissue seems an interesting specimen to detect multiple cannabis use, and brain may serve as an alternative specimen for blood; nevertheless, the present findings should be substantiated by further investigations. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Toxicological relevance of pharmaceuticals in drinking water.

PubMed

Bruce, Gretchen M; Pleus, Richard C; Snyder, Shane A

2010-07-15

Interest in the public health significance of trace levels of pharmaceuticals in potable water is increasing, particularly with regard to the effects of long-term, low-dose exposures. To assess health risks and establish target concentrations for water treatment, human health risk-based screening levels for 15 pharmaceutically active ingredients and four metabolites were compared to concentrations detected at 19 drinking water treatment plants across the United States. Compounds were selected based on rate of use, likelihood of occurrence, and potential for toxicity. Screening levels were established based on animal toxicity data and adverse effects at therapeutic doses, focusing largely on reproductive and developmental toxicity and carcinogenicity. Calculated drinking water equivalent levels (DWELs) ranged from 0.49 microg/L (risperidone) to 20,000 microg/L (naproxen). None of the 10 detected compounds exceeded their DWEL. Ratios of DWELs to maximum detected concentrations ranged from 110 (phenytoin) to 6,000,000 (sulfamethoxazole). Based on this evaluation, adverse health effects from targeted pharmaceuticals occurring in U.S. drinking water are not expected.

Spatio-temporal evaluation of emerging contaminants and their partitioning along a Brazilian watershed.

PubMed

de Sousa, Diana Nara Ribeiro; Mozeto, Antonio Aparecido; Carneiro, Renato Lajarim; Fadini, Pedro Sergio

2018-02-01

The occurrence, partitioning, and spatio-temporal distribution of seven pharmaceuticals for human use, three steroid hormones and one personal care product were determined in surface water, suspended particulate matter (SPM), and sediment of Piraí Creek and Jundiaí River (Jundiaí River Basin, São Paulo, Brazil). The maximum average detected concentrations of the compounds in the Piraí River samples were < 30 ng L -1 , except for caffeine (222 ng L -1 ). In Jundiaí River samples, most of the compounds were frequently detected, wherein caffeine had the highest concentration, with maximum average concentrations of 14,050 ng L -1 , followed by atenolol (431 ng L -1 ), ibuprofen (268 ng L -1 ) and diclofenac (214 ng L -1 ). Atenolol, propranolol, estrone, and triclosan were the contaminants most frequently detected in sediment and SPM samples. Triclosan had the highest average proportion of SPM as opposed to in the aqueous phase (> 75%). Contaminants with acid functional groups showed, in general, a lower tendency to bind to particulate matter and sediments. In addition, hydrophobicity had an important effect on their environmental partitioning. The spatial distribution of contaminants along the Jundiaí River was mainly affected by the higher concentration of contaminants in water samples collected downstream from a sewage treatment plant (STP). The results obtained here clearly showed the importance of the analysis of some contaminants in the whole water, meaning both dissolved and particulate compartments in the water, and that the partitioning is ruled by a set of parameters associated to the physicochemical characteristics of contaminants and the matrix properties of the studied, which need be considered in an integrated approach to understand the fate of emerging chemical contaminants in aquatic environments.

Occurrence and levels of glyphosate and AMPA in shallow lakes from the Pampean and Patagonian regions of Argentina.

PubMed

Castro Berman, M; Marino, D J G; Quiroga, María Victoria; Zagarese, Horacio

2018-06-01

Glyphosate (N-(phosphonomethyl)glycine) is a broad-spectrum systemic herbicide used to kill weeds that compete with commercial crops. In Argentina, the use of glyphosate-based herbicides increased dramatically (up to ∼200,000 tons on 2012) since the introduction of glyphosate-resistant crops, such as transgenic soy and resistant corn, and the adoption of non-till practices in the 1990's. Sallow lakes within the Pampa region may be potentially impacted by continuous herbicide usage. We surveyed 52 shallow lakes from the Pampa region (Buenos Aires Province, Argentina) to assess the occurrence and concentrations of glyphosate and its main degradation product (AMPA). For comparison, we also sampled 24 shallow lakes from an area with no agricultural use of glyphosate (Northern Patagonia). Glyphosate and AMPA were analyzed by UPLC-MS/MS ESI (±) in lake water, suspended particulate matter (SPM), and sediment samples. Within the Pampa region, glyphosate residues were detected in >40% of samples. Glyphosate residues were detected more frequently in sediment and surface water than in SPM samples. The mean (maximum) concentrations of glyphosate were 2.11 (4.52) μg l -1 for surface water; 0.10 (0.13) μg l -1 for SPM and 10.47 (20.34) μg kg -1 for sediment samples, respectively. Whereas, mean (maximum) concentrations of AMPA were 0.84 and (0.90) μg l -1 for surface water; 0.07 (0.07) μg l -1 for SPM; and 22.53 (32.89) μg kg -1 for sediment samples. The herbicide was not detected in samples from the Patagonian region. To our knowledge, this is the first study reporting the occurrence and concentrations of the herbicide in freshwater lakes of Argentina. Copyright © 2018 Elsevier Ltd. All rights reserved.

Tritium concentrations in flow from selected springs that discharge to the Snake River, Twin Falls-Hagerman area, Idaho

USGS Publications Warehouse

Mann, L.J.

1989-01-01

Concern has been expressed that some of the approximately 30,900 curies of tritium disposed to the Snake River Plain aquifer from 1952 to 1988 at the INEL (Idaho National Engineering Laboratory) have migrated to springs discharging to the Snake River in the Twin Falls-Hagerman area. To document tritium concentrations in springflow, 17 springs were sampled in November 1988 and 19 springs were sampled in March 1989. Tritium concentrations were less than the minimum detectable concentration of 0.5 pCi/mL (picocuries/mL) in November 1988 and less than the minimum detectable concentration of 0.2 pCi/mL in March 1989; the minimum detectable concentration was smaller in March 1989 owing to a longer counting time in the liquid scintillation system. The maximum contaminant level of tritium in drinking water as established by the U.S. Environmental Protection Agency is 20 pCi/mL. U.S. Environmental Protection Agency sample analyses indicate that the tritium concentration has decreased in the Snake River near Buhl since the 1970's. In 1974-79, tritium concentrations were less than 0.3 +/-0.2 pCi/mL in 3 of 20 samples; in 1983-88, 17 of 23 samples contained less than 0.3 +/-0.2 pCi/mL of tritium; the minimum detectable concentration is 0.2 pCi/mL. On the basis of decreasing tritium concentrations in the Snake River, their correlation to cessation of atmospheric weapons tests tritium concentrations in springflow less than the minimum detectable concentration, and the distribution of tritium in groundwater at the INEL, aqueous disposal of tritium at the INEL has had no measurable effect on tritium concentrations in springflow from the Snake River Plain aquifer and in the Snake River near Buhl. (USGS)

Soil, water, and streambed quality at a demolished asphalt plant, Fort Bragg, North Carolina, 1992-94

USGS Publications Warehouse

Campbell, T.R.

1996-01-01

A number of potentially hazardous chemicals were used at an asphalt plant on the Fort Bragg U.S. Army Reservation near Fayetteville, North Carolina. This plant was demolished in the late 1960's. Samples collected from soil, ground water, surface water, and streambed sediment were tested for the presence of contaminants. The sediment immediately underlying the demolished asphalt plant site consists mainly of sands, silts, and clayey sands with interbedded clay occurring at various depths. About 12 inches of rainfall per year infiltrate the unconfined surficial aquifer. The water table in this area is about 233 to 243 feet above sea level. Local ground water moves laterally, mainly towards the north- to-northwest at a rate of about 35 feet per year. where it discharges to Tank Creek, Little River, or one of their tributaries. A series of confining clays separate the surficial aquifer from the underlying upper Cape Fear aquifer. These clays help retard vertical migration of constituents dissolved in ground water. The saprolite-bedrock aquifer lies below the upper Cape Fear aquifer. In general ground water in the seven monitoring wells screened in the upper and lower part of the surficial aquifer did not contain detectable concentrations of chemicals related to past asphalt-plant activities. A small number of chemicals that were assumed to be unrelated to the asphalt plant were present in some of the study area monitoring wells. Ground water in four wells contained concentrations of organochlorine pesticides. Of these pesticides, concentrations of gamma-benzene hexachloride (lindane) (maximum of 0.76 micrograms per liter) exceeded the U.S. Environmental Protection Agency maximum contaminant level of 0.2 micrograms per liter in two wells. In addition, one well contained a trichloroethane concentration (7.7 micrograms per liter) that is assumed to be unrelated to demolished asphalt-plant operations, but exceeded the U.S. Environmental Protection Agency maximum contaminant level of 5.0 micrograms per liter. One well contained a fluoride concentration of 5.2 milligrams per liter that exceeded the U.S. Environmental Protection Agency maximum contaminant level of 4.0 milligrams per liter. Total and dissolved metals concentrations were generally typical of background levels. Some of the wells contained elevated levels of chloride (maximum of 749 milligrams per liter), specific conductance (maximum of 2,780 microsiemens per centimeter at 25 degrees Celsius), and dissolved solids (maximum of 1,520 milligrams per liter). Twelve of twenty-two soil samples that were collected at various depths at monitoring-well locations did not contain volatile organic compounds or polynuclear aromatic hydrocarbons. The remaining ten soil samples contained very low concentrations of polynuclear aromatic hydrocarbons and (or) analytical laboratory-related volatile organic compounds. The maximum concentrations were for fluoranthene and pyrene, at 780 and 750 micrograms per kilogram, respectively. In general, the polynuclear aromatic hydrocarbon concentrations were in sediment near the land surface. Streambed sediment from an unnamed, eastern tributary to Tank Creek in the eastern part of the site contained a small number of organochlorine pesticide compounds (a maximum of 1,400 milligrams per kilogram of 4,4'-DDD) and total petroleum hydrocarbons (113 milligrams per kilogram). Concentrations of metals and other inorganic constituents were generally typical of background concentrations. Surface water in this tributary did not contain elevated concentrations of anthropogenic chemicals.

Elevated radioxenon detected remotely following the Fukushima nuclear accident.

PubMed

Bowyer, T W; Biegalski, S R; Cooper, M; Eslinger, P W; Haas, D; Hayes, J C; Miley, H S; Strom, D J; Woods, V

2011-07-01

We report on the first measurements of short-lived gaseous fission products detected outside of Japan following the Fukushima nuclear releases, which occurred after a 9.0 magnitude earthquake and tsunami on March 11, 2011. The measurements were conducted at the Pacific Northwest National Laboratory (PNNL), (46°16'47″N, 119°16'53″W) located more than 7000 km from the emission point in Fukushima Japan (37°25'17″N, 141°1'57″E). First detections of (133)Xe were made starting early March 16, only four days following the earthquake. Maximum concentrations of (133)Xe were in excess of 40 Bq/m(3), which is more than ×40,000 the average concentration of this isotope is this part of the United States. 2011. Published by Elsevier Ltd.

The distribution of antibiotics in water of a river basin in South China

NASA Astrophysics Data System (ADS)

Meng, T.; Cheng, W.; Wang, M.; Wan, T.; Cheng, M.; Zhang, C. C.; Jia, Z. Y.

2017-08-01

In water environment field, one of the most attractive research topics is the determination of contamination characteristics of antibiotics in water. In order to investigate the distribution of antibiotics in surface water and drinking water of a certain river basin in southern China, we determined the types and concentrations of antibiotics that contaminated the river by performing HPLC-ESI-MS/MS method. Thus, we detected 17 antibiotics in four surface water samples (B1, B2, B3, and B4). In sampling points B3 and B4, we detected 16 antibiotics separately. The detection rates of norfloxacin, ofloxacin, and erythromycin-H2O were 100%, and the antibiotic erythromycin-H2O had the maximum concentration. In six drinking water samples (A1, A2, A3, A4, A5, and A6), we detected 13 antibiotics. In A5 water samples, we detected all the 13 antibiotics. The detection rate of ofloxacin and erythromycin-H2O was 100%, and erythromycin-H2O was the antibiotic with the highest concentration. We also found that from the upstream to the downstream of the river basin, the types of antibiotics in river increased gradually. In the upstream water samples (B1), we detected three antibiotics. Erythromycin-H2O was the antibiotic with the highest concentration of 6.61 ng/L, and sulfapyridine had the lowest concentration of 2.82 ng/L. In the downstream water samples (B4), we detected 16 antibiotics. Erythromycin-H2O was the antibiotic with the highest concentration of 277.58 ng/L, and the Sulfamonomethoxine was the antibiotic with the second-highest concentration of 242.1 ng/L. In addition, different membrane treatment processes could remove different amounts of antibiotics from the water samples. The study is an important reference for providing environmental protection to river water basin.

Occurrence and distribution of organic chemicals and nutrients and comparison of water-quality data from public drinking-water supplies in the Columbia aquifer in Delaware, 2000-08

USGS Publications Warehouse

Reyes, Betzaida

2010-01-01

The U.S. Geological Survey, in cooperation with the Delaware Department of Natural Resources and Environmental Control and the Delaware Geological Survey, conducted a groundwater-quality investigation to (a) describe the occurrence and distribution of selected contaminants, and (b) document any changes in groundwater quality in the Columbia aquifer public water-supply wells in the Coastal Plain in Delaware between 2000 and 2008. Thirty public water-supply wells located throughout the Columbia aquifer of the Delaware Coastal Plain were sampled from August through November of 2008. Twenty-two of the wells in the sampling network for this project were previously sampled in 2000. Eight new wells were selected to replace wells no longer in use. Groundwater collected from the wells was analyzed for the occurrence and distribution of selected pesticides, pesticide degradates, volatile organic compounds, nutrients, and major inorganic ions. Nine of the wells were analyzed for radioactive elements (radium-226, radium-228, and radon). Groundwater-quality data were compared for sites sampled in both 2000 and 2008 to document any changes in water quality. One or more pesticides were detected in samples from 29 of the 30 wells. There were no significant differences in pesticide and pesticide degradate concentrations and similar compounds were detected when comparing sampling results from 2000 and 2008. Pesticide and pesticide degradate concentrations were generally less than 1 microgram per liter. Twenty-four compounds, 14 pesticides, and 10 pesticide degradates were detected in at least one sample; the pesticide degradates, metolachlor ethanesulfonic acid, deethylatrazine, and alachlor ethanesulfonic acid were the most frequently detected compounds, each found in more than 50 percent of samples. Almost 80 percent of the detected pesticides were agricultural herbicides, which reflects the prevalence and wide distribution of agriculture in sampled areas, as well the dominance of agricultural pesticides among the target analytes for this study. No concentration of a pesticide or pesticide degradate exceeded any regulatory standard. Dieldrin, an insecticide that has been banned for several decades, was detected at a concentration that exceeded a non-regulatory health-based screening level of 0.002 micrograms per liter at nine sites. Volatile organic compounds (VOCs) were generally detected at concentrations of less than 1 microgram per liter, although 7 of the 31 detected VOCs had concentrations greater than 1 microgram per liter. There were no significant differences in VOC concentrations from 2000 to 2008; however, among the resampled wells, the mean number of VOCs detected per well was significantly different over the 8-year period. The number of VOCs detected per well decreased in 73 percent of the resampled wells; the decrease ranged from one to eight fewer detections in 2008 than in 2000. Chloroform and methyl tert-butyl ether were the most frequently detected VOCs, at 90 percent and 63 percent, respectively, among the 30 wells. Solvents were the most frequently detected class of VOCs. All measured concentrations of VOCs in groundwater were below established standards for drinking water and below other health-based guidelines. There were no significant differences in nutrient or major-ion concentrations between 2000 and 2008, however, the medians of two field measurements, pH and dissolved oxygen, were significantly higher in 2008 than in 2000 in the resampled wells. Although pH and dissolved oxygen were higher, water was still acidic and predominantly oxic. Nitrate was the predominant nutrient species in the Columbia aquifer, with a 90-percent detection frequency. The median nitrate concentration in groundwater was 4.88 milligrams per liter, which was slightly lower than, but not significantly different from, the median of 5.23 milligrams per liter for the 2000 samples. Concentrations of nitrate exceeded the U.S. Environmental Protection Agency's Maximum Contaminant Level or Federal drinking-water standard of 10 milligrams per liter as nitrogen in samples from two wells. Eight of the 30 wells sampled had iron or manganese concentrations that exceeded the U.S. Environmental Protection Agency's Secondary Maximum Contaminant Level; nine samples exceeded the Health Advisory Limit set by the Delaware Division of Public Health of 20 milligrams per liter for sodium in drinking water. Two radiochemical isotopes, radium-226 and radon-222, were detected in all nine groundwater samples analyzed; five samples had detectable levels of radium-228 activity. None of the samples exceeded the U.S Environmental Protection Agency's Maximum Contaminant Level for radium or radon in drinking water. Although radioactive elements were more frequently detected in 2008 than in 2000, this increased detection frequency is more likely due to lower detection levels in 2008 than 2000. The average age of groundwater entering the screens of the production wells sampled in 2008 ranged from 6 to 35 years, with a median groundwater age of 22 years. Groundwater age was positively correlated with well depth and negatively correlated with dissolved oxygen. Data from the 22 resampled wells indicate a significant positive difference in the average modeled groundwater-sample-age results. The average groundwater age from samples collected in 2008 was generally 7 years older than the average groundwater age from samples collected in 2000.

Water quality in alluvial aquifers of the southern Rocky Mountains Physiographic Province, upper Colorado River basin, Colorado, 1997

USGS Publications Warehouse

Apodaca, Lori Estelle; Bails, Jeffrey B.

2000-01-01

Water-quality samples were collected in the summer of 1997 from 45 sites (43 wells and 2 springs) in selected alluvial aquifers throughout the Southern Rocky Mountains physiographic province of the Upper Colorado River Basin study unit as part of the U.S. Geological Survey National Water-Quality Assessment Program. The objective of this study was to assess the water-quality conditions in selected alluvial aquifers in the Southern Rocky Mountains physiographic province. Alluvial aquifers are productive aquifers in the Southern Rocky Mountains physiographic province and provide for easily developed wells. Water-quality samples were collected from areas where ground water is used predominantly for domestic or public water supply. Twenty-three of the 45 sites sampled were located in or near mining districts. No statistical differences were observed between the mining sites and sites not associated with mining activities for the majority of the constituents analyzed. Water samples were analyzed for major ions, nutrients, dissolved organic carbon, trace elements, radon-222, pesticides, volatile organic compounds, bacteria, and methylene blue active substances. In addition, field parameters consisting of water temperature, specific conductance, dissolved oxygen, pH, turbidity, and alkalinity were measured at all sites.Specific conductance for the ground-water sites ranged from 57 to 6,650 microsiemens per centimeter and had higher concentrations measured in areas such as the northwestern part of the study unit. Dissolved oxygen ranged from 0.1 to 6.0 mg/L (milligrams per liter) and had a median concentration of 2.9 mg/L. The pH field values ranged from 6.1 to 8.1; about 4 percent of the sites (2 of 45) had pH values outside the range of 6.5 to 8.5 and so did not meet the U.S. Environmental Protection Agency secondary maximum contaminant level standard for drinking water. About 5 percent (2 of 43) of the samples exceeded the U.S. Environmental Protection Agency recommended turbidity value of 5 nephelometric turbidity units; one of these samples was from a monitoring well. The U.S. Environmental Protection Agency secondary maximum contaminant levels for dissolved solids, sulfate, iron, and manganese were exceeded at some of the sites. Higher dissolved-solids concentrations were detected where sedimentary rocks are exposed, such as in the northwestern part of the Southern Rocky Mountains physiographic province. The dominant water compositions for the sites sampled are calcium, magnesium, and bicarbonate. However, sites in areas where sedimentary rocks are exposed and sites located in or near mining areas show more sulfate-dominated waters. Nutrient concentrations were less than the U.S. Environmental Protection Agency drinking-water standards. Only one site had a nitrate concentration greater than 3.0 mg/L, a level indicating possible influence from human activities. No significant differences among land-use/land-cover classifications (forest, rangeland, and urban) for drinking-water wells (42 sites) were identified for dissolved-solids, sulfate, nitrate, iron or manganese concentrations. Radon concentrations were higher in parts of the study unit where Precambrian rocks are exposed. All radon concentrations in ground water exceeded the previous U.S. Environmental Protection Agency proposed maximum contaminant level for drinking water, which has been withdrawn pending further review.Pesticide detections were at concentrations below the reporting limits and were too few to allow for comparison of the data. Eight volatile organic compounds were detected at six sites; all concentrations complied with U.S. Environmental Protection Agency drinking-water standards. Total coliform bacteria were detected at six sites, but no Escherichia coli (E. coli) was detected. Methylene blue active substances were detected at three sites at concentrations just above the reporting limit. Overall, the water quality in the Southern Rocky Mountains physiograph

Ground-Water Levels and Water-Quality Data for Wells in the Crumpton Creek Area near Arnold Air Force Base, Tennessee, November 2001 to January 2002

USGS Publications Warehouse

Williams, Shannon D.

2003-01-01

From November 2001 to January 2002, a study of the ground-water resources in the Crumpton Creek area of Middle Tennessee was conducted to determine whether volatile organic compounds (VOCs) from Arnold Air Force Base (AAFB) have affected local private water supplies and to advance understanding of the ground-water-flow system in this area. VOC samples were collected from private wells that were not included in previous sampling efforts conducted in the Crumpton Creek area near AAFB. Ground-water-flow directions were investigated by measuring water levels in wells and constructing a potentiometric-surface map of the Manchester aquifer in the study area. Data were collected from a total of 68 private wells, 82 monitoring wells, and 1 cave during the period of study. Ground-water levels were determined for 42 of the private wells and for all 82 monitoring wells. Of the 82 monitoring wells, 81 withdraw water from the Manchester aquifer and 1 well withdraws water from the overlying shallow aquifer. The Manchester aquifer wells range in depth from 20 to 150 feet. Water-level altitudes for the Manchester aquifer ranged from 956 to 1,064 feet above the National Geodetic Vertical Datum of 1929. Water levels ranged from approximately 6 feet above land surface to 94 feet below land surface. Water-quality samples were collected from all 68 private wells, 8 of the monitoring wells, and the 1 cave. Of the 55 VOCs analyzed, 42 were not detected. Thirteen VOCs were detected; however, only tetrachloroethylene (PCE), methylene chloride, and toluene were detected at concentrations equal to or above reporting levels for the analytical method used. PCE was detected in water samples from 15 private wells and was the only VOC that exceeded drinking water maximum contaminant levels for public water systems. PCE concentrations in samples from five of the wells were below the reporting level and ranged from estimated concentrations of 0.46 to 0.80 microgram per liter (?g/L). Samples from 10 wells contained concentrations equal to or greater than the analytical reporting level of 1 ?g/L for PCE. Samples from one of these wells contained PCE concentrations (12 ?g/L and 11 ?g/L) exceeding the drinking water maximum contaminant level of 5 ?g/L for PCE. The spatial distribution of PCE detections and the relative concentrations of PCE and trichloroethylene suggest that the PCE detections are associated with a small and localized ground-water contamination plume unrelated to AAFB ground-water contamination.

Distribution of volatile organic compounds (VOCs) in surface water, soil, and groundwater within a chemical industry park in Eastern China.

PubMed

Liu, Benhua; Chen, Liang; Huang, Linxian; Wang, Yongseng; Li, Yuehua

2015-01-01

This paper focuses on the distribution of volatile organic compounds (VOCs) in the surface water, soil, and groundwater within a chemical industry park in Eastern China. At least one VOC was detected in each of the 20 sampling sites, and the maximum number of VOCs detected in the surface water, groundwater, and soil were 13, 16, and 14, respectively. Two of the 10 VOCs with elevated concentrations detected in surface water, groundwater, and soil were chloroform and 1,2-dichloroethane. The characteristics of VOCs, which include volatility, boiling point, and solubility, could significantly affect their distribution in surface water, soil, and groundwater. However, due to the direct discharging of chemical industry wastewater into surface water, higher concentrations of VOCs (except chloroform) were detected in surface water than in soil and groundwater. Fortunately, the higher volatility of VOCs prevents the VOCs from impacting groundwater, which helps to maintain a lower concentration of VOCs in the groundwater than in both surface water and soil. This is because pollutants with relatively higher boiling points and lower solubilities have higher detection frequencies in soil, and contaminants with relatively lower boiling points and higher solubilities have higher detection frequencies in water, notably in surface water.

Occurrence and concentrations of pharmaceutical compounds in groundwater used for public drinking-water supply in California.

PubMed

Fram, Miranda S; Belitz, Kenneth

2011-08-15

Pharmaceutical compounds were detected at low concentrations in 2.3% of 1231 samples of groundwater (median depth to top of screened interval in wells=61 m) used for public drinking-water supply in California. Samples were collected statewide for the California State Water Resources Control Board's Groundwater Ambient Monitoring and Assessment (GAMA) Program. Of 14 pharmaceutical compounds analyzed, 7 were detected at concentrations greater than or equal to method detection limits: acetaminophen (used as an analgesic, detection frequency 0.32%, maximum concentration 1.89 μg/L), caffeine (stimulant, 0.24%, 0.29 μg/L), carbamazepine (mood stabilizer, 1.5%, 0.42 μg/L), codeine (opioid analgesic, 0.16%, 0.214 μg/L), p-xanthine (caffeine metabolite, 0.08%, 0.12 μg/L), sulfamethoxazole (antibiotic, 0.41%, 0.17 μg/L), and trimethoprim (antibiotic, 0.08%, 0.018 μg/L). Detection frequencies of pesticides (33%), volatile organic compounds not including trihalomethanes (23%), and trihalomethanes (28%) in the same 1231 samples were significantly higher. Median detected concentration of pharmaceutical compounds was similar to those of volatile organic compounds, and higher than that of pesticides. Pharmaceutical compounds were detected in 3.3% of the 855 samples containing modern groundwater (tritium activity>0.2 TU). Pharmaceutical detections were significantly positively correlated with detections of urban-use herbicides and insecticides, detections of volatile organic compounds, and percentage of urban land use around wells. Groundwater from the Los Angeles metropolitan area had higher detection frequencies of pharmaceuticals and other anthropogenic compounds than groundwater from other areas of the state with similar proportions of urban land use. The higher detection frequencies may reflect that groundwater flow systems in Los Angeles area basins are dominated by engineered recharge and intensive groundwater pumping. Published by Elsevier B.V.

Plasma dispositions and concentrations of ivermectin in eggs following treatment of laying hens.

PubMed

Cirak, V Y; Aksit, D; Cihan, H; Gokbulut, C

2018-05-01

To determine the plasma disposition and concentrations of ivermectin (IVM) in eggs produced by laying hens following S/C, oral and I/V administration. Twenty-four laying hens, aged 37 weeks and weighing 1.73 (SD 0.12) kg were allocated to three groups of eight birds. The injectable formulation of IVM was administered either orally, S/C, or I/V, at a dose of 0.2 mg/kg liveweight, following dilution (1:5, v/v) with propylene glycol. Heparinised blood samples were collected at various times between 0.25 hours and 20 days after drug administration. Eggs produced by hens were also collected daily throughout the study period. Samples of plasma and homogenised egg were analysed using HPLC. Maximum concentrations of IVM in plasma and mean residence time of IVM were lower after oral (10.2 (SD 7.2) ng/mL and 0.38 (SD 0.14) days, respectively) than after S/C (82.9 (SD 12.4) ng/mL and 1.05 (SD 0.24) days, respectively) administration (p<0.01). The time to maximum concentration and elimination half-life were shorter following oral (0.14 (SD 0.04) and 0.23 (SD 0.11) days, respectively) than S/C (0.25 (SD 0.00) and 1.45 (SD 0.45) days, respectively) administration (p<0.01). IVM was first detected in eggs 2 days after treatment in all groups and was detected until 8 days after oral and I/V administration, and until 15 days after S/C administration. Peak concentrations of IVM were 15.7, 23.3 and 1.9 µg/kg, observed 2, 5 and 4 days after I/V, S/C and oral administration, respectively. The low plasma bioavailability of IVM observed after oral administration in laying hens could result in lower efficacy or subtherapeutic plasma concentrations, which may promote the development of parasitic drug resistance. Due to high IVM residues in eggs compared to the maximum residue limits for other food-producing animal species, a withdrawal period should be necessary for eggs after IVM treatment in laying hens.

Occurrence of pharmaceutical compounds in wastewater process streams in Dublin, Ireland.

PubMed

Lacey, Clair; Basha, Shaik; Morrissey, Anne; Tobin, John M

2012-01-01

The aim of this work is to establish baseline levels of pharmaceuticals in three wastewater treatment plant (WWTP) streams in the greater Dublin region to assess the removal efficiency of the selected WWTPs and to investigate the existence of any seasonal variability. Twenty compounds including several classes of antibiotics, acidic and basic pharmaceuticals, and prescribed medications were selected for investigation using a combination of membrane filtration, solid phase extraction (SPE) cleanup, and liquid chromatography-electrospray ionization tandem mass spectrometry. Fourteen of the selected compounds were found in the samples. Increased effluent concentrations, compared to influent concentrations, for a number of compounds (carbamazepine, clotrimazole, propranolol, nimesulide, furosemide, mefenamic acid, diclofenac, metoprolol, and gemfibrozil) were observed. The detected concentrations were generally below toxicity levels and based on current knowledge are unlikely to pose any threat to aquatic species. Mefenamic acid concentrations detected in both Leixlip and Swords effluents may potentially exert ecotoxicological effects with maximum risk quotients (i.e., ratio of predicted exposure concentration to predicted no effect concentration) of 4.04 and 1.33, respectively.

Effects of herbicide usage on water quality of selected streams in Wyoming

USGS Publications Warehouse

Butler, David L.

1980-01-01

During 1977 and 1978 the Wyoming Department of Agriculture, in conjunction with county weed and pest control districts, conducted a noxious-weed-control program in Wyoming. The herbicides primarily used were picloram, 2,4-D, and dicamba. The U.S. Geological Survey, in cooperation with the Wyoming Department of Agriculture, sampled and analyzed water from selected streams for these herbicides plus silvex; 2,4,5-T; and 2,4-DP.This report contains data for samples collected during 1977 and 1978. The most commonly detected herbicides in water samples were 2,4-D with 41-percent nonzero values and picloram with 34.5-percent nonzero values. Herbicide occurrence in bottom-material samples was uncommon; dicamba was found with 9-percent nonzero values. The maximum herbicide concentration in water was 1.1 micrograms per liter of 2,4-D, and the maximum herbicide concentration in bottom material was 8.0 micrograms per kilogram of 2,4-D. Based on available toxicity data and water-quality criteria, these herbicide concentrations do not constitute dangerous or harmful concentrations to humans or to the environment.

Assessment of heavy metal pollution in Republic of Macedonia using a plant assay.

PubMed

Gjorgieva, Darinka; Kadifkova-Panovska, Tatjana; Bačeva, Katerina; Stafilov, Trajče

2011-02-01

Different plant organs (leaves, flowers, stems, or roots) from four plant species-Urtica dioica L. (Urticaceae), Robinia pseudoacacia L. (Fabaceae), Taraxacum officinale (Asteraceae), and Matricaria recutita (Asteraceae)-were evaluated as possible bioindicators of heavy-metal pollution in Republic of Macedonia. Concentrations of Pb, Cu, Cd, Mn, Ni, and Zn were determined in unwashed plant parts collected from areas with different degrees of metal pollution by ICP-AES. All these elements were found to be at high levels in samples collected from an industrial area. Maximum Pb concentration was 174.52 ± 1.04 mg kg⁻¹ in R. pseudoacacia flowers sampled from the Veles area, where lead and zinc metallurgical activities were present. In all control samples, the Cd concentrations were found to be under the limit of detection (LOD <0.1 mg kg⁻¹) except for R. pseudoacacia flowers and T. officinale roots. The maximum Cd concentration was 7.97 ± 0.15 mg kg⁻¹ in R. pseudoacacia flowers from the Veles area. Nickel concentrations were in the range from 1.90 ± 0.04 to 5.74 ± 0.03 mg kg⁻¹. For U. dioica leaves and R. pseudoacacia flowers sampled near a lead-smelting plant, concentrations of 465.0 ± 0.55 and 403.56 ± 0.34 mg kg⁻¹ Zn were detected, respectively. In all control samples, results for Zn were low, ranging from 10.2 ± 0.05 to 38.70 ± 0.18 mg kg⁻¹. In this study, it was found that the flower of R. pseudoacacia was a better bioindicator of heavy-metal pollution than other plant parts. Summarizing the results, it can be concluded that T. officinale, U. dioica, and R. pseudoacacia were better metal accumulators and M. recutita was a metal avoider.

Mercury in Indiana watersheds: retrospective for 2001-2006

USGS Publications Warehouse

Risch, Martin R.; Baker, Nancy T.; Fowler, Kathleen K.; Egler, Amanda L.; Lampe, David C.

2010-01-01

Information about total mercury and methylmercury concentrations in water samples and mercury concentrations in fish-tissue samples was summarized for 26 watersheds in Indiana that drain most of the land area of the State. Mercury levels were interpreted with information on streamflow, atmospheric mercury deposition, mercury emissions to the atmosphere, mercury in wastewater, and landscape characteristics. Unfiltered total mercury concentrations in 411 water samples from streams in the 26 watersheds had a median of 2.32 nanograms per liter (ng/L) and a maximum of 28.2 ng/L. When these concentrations were compared to Indiana water-quality criteria for mercury, 5.4 percent exceeded the 12-ng/L chronic-aquatic criterion, 59 percent exceeded the 1.8-ng/L Great Lakes human-health criterion, and 72.5 percent exceeded the 1.3-ng/L Great Lakes wildlife criterion. Mercury concentrations in water were related to streamflow, and the highest mercury concentrations were associated with the highest streamflows. On average, 67 percent of total mercury in streams was in a particulate form, and particulate mercury concentrations were significantly lower downstream from dams than at monitoring stations not affected by dams. Methylmercury is the organic fraction of total mercury and is the form of mercury that accumulates and magnifies in food chains. It is made from inorganic mercury by natural processes under specific conditions. Unfiltered methylmercury concentrations in 411 water samples had a median of 0.10 ng/L and a maximum of 0.66 ng/L. Methylmercury was a median 3.7 percent and maximum 64.8 percent of the total mercury in 252 samples for which methylmercury was reported. The percentages of methylmercury in water samples were significantly higher downstream from dams than at other monitoring stations. Nearly all of the total mercury detected in fish tissue was assumed to be methylmercury. Fish-tissue samples from the 26 watersheds had wet-weight mercury concentrations that exceeded the 0.3 milligram per kilogram (mg/kg) U.S. Environmental Protection Agency (USEPA) methylmercury criterion in 12.4 percent of the 1,731 samples. The median wet-weight concentration in the fish-tissue samples was 0.13 mg/kg, and the maximum was 1.07 mg/kg. A coarse-scale analysis of all fish-tissue data in each watershed and a fine-scale analysis of data within 5 kilometers (km) of the downstream end of each watershed showed similar results overall. Mercury concentrations in fish-tissue samples were highest in the White River watershed in southern Indiana and the Fall Creek watershed in central Indiana. In fish-tissue samples within 5 km of the downstream end of a watershed, the USEPA methylmercury criterion was exceeded by 45 percent of mercury concentrations from the White River watershed and 40 percent of the mercury concentration from the Fall Creek watershed. A clear relation between mercury concentrations in fish-tissue samples and methylmercury concentrations in water was not observed in the data from watersheds in Indiana. Average annual atmospheric mercury wet-deposition rates were mapped with data at 156 locations in Indiana and four surrounding states for 2001-2006. These maps revealed an area in southeastern Indiana with high mercury wet-deposition rates-from 15 to 19 micrograms per square meter per year (ug/m2/yr). Annual atmospheric mercury dry-deposition rates were estimated with an inferential method by using concentrations of mercury species in air samples at three locations in Indiana. Mercury dry deposition-rates were 5.6 to 13.6 ug/m2/yr and were 0.49 to 1.4 times mercury wet-deposition rates. Total mercury concentrations were detected in 96 percent of 402 samples of wastewater effluent from 50 publicly owned treatment works in the watersheds; the median concentration was 3.0 ng/L, and the maximum was 88 ng/L. When these concentrations were compared to Indiana water-quality criteria for mercury, 12 percent exceeded the 12-n

Use of otolith for detecting strontium-90 in fish from the harbor of Fukushima Dai-ichi Nuclear Power Plant.

PubMed

Fujimoto, Ken; Miki, Shizuho; Kaeriyama, Hideki; Shigenobu, Yuya; Takagi, Kaori; Ambe, Daisuke; Ono, Tsuneo; Watanabe, Tomowo; Morinaga, Kenji; Nakata, Kaoru; Morita, Takami

2015-06-16

To clarify the level of contamination with radioactive cesium (radiocesium) discharged from Fukushima Dai-ichi Nuclear Power Plant (FDNPP), three fish species caught in the main harbor of FDNPP were subjected to γ-ray analysis. The concentration of radiocesium in muscle differed among individual fish, even those of similar size of the same species, and showed little relation to the standard length of fish. The maximum concentration of radiocesium (202 kBq/kg wet) was detected from fat greenling samples. A comparison to data from outside the port indicated that the level of radiocesium contamination inside the port was higher than that outside. We found that β-rays were emitted from otoliths of fishes caught in the port of FDNPP. β-ray intensities were correlated with the concentrations of radiocesium in muscles of the three fish species. In Japanese rockfish, the β-ray count rates from otoliths were significantly correlated with the concentration of radiocesium and (90)Sr in the whole body without internal organs of Japanese rockfish. However, no β-rays were detected from brown hakeling samples collected around FDNPP, suggesting that the detection of β-rays from otoliths may indicate living in the main harbor of FDNPP.

Deposition of chromium in aquatic ecosystem from effluents of handloom textile industries in Ranaghat-Fulia region of West Bengal, India.

PubMed

Sanyal, Tanmay; Kaviraj, Anilava; Saha, Subrata

2015-11-01

Accumulation of chromium (Cr) was determined in water, sediment, aquatic plants, invertebrates and fish in aquatic ecosystems receiving effluents from handloom textile industries in Ranaghat-Fulia region of West Bengal in India. Cr was determined in the samples by atomic absorption spectrophotometer and data were analyzed functionally by Genetic Algorithm to determine trend of depositions of Cr in the sediment and water. Area plot curve was used to represent accumulation of Cr in biota. The results indicate that the aquatic ecosystems receiving the effluents from handloom textile factories are heavily contaminated by Cr. The contamination is hardly reflected in the concentration of Cr in water, but sediment exhibits seasonal fluctuation in deposition of Cr, concentration reaching to as high as 451.0 μg g(-1) during the peak production period. There is a clear trend of gradual increase in the deposition of Cr in the sediment. Aquatic weed, insect and mollusk specimens collected from both closed water bodies (S1 & S2) and riverine resources (S3 & S4) showed high rate of accumulation of Cr. Maximum concentration of Cr was detected in roots of aquatic weeds (877.5 μg g(-1)). Fish specimens collected from the polluted sites (S3 & S4) of river Churni showed moderate to high concentration of Cr in different tissues. Maximum concentration was detected in the liver of Glossogobius giuris (679.7 μg g(-1)) during monsoon followed by gill of Mystus bleekeri (190.0 μg g(-1)) and gut of G. giuris (123.7 μg g(-1)) during summer. Eutropiichthys vacha showed moderately high concentration of Cr in different tissues (65-99 μg g(-1)) while Puntius sarana showed relatively low concentration of Cr (below detection limit to 18.0 μg g(-1)) in different tissues except in gill (64.4 μg g(-1)).

Deposition of chromium in aquatic ecosystem from effluents of handloom textile industries in Ranaghat–Fulia region of West Bengal, India

PubMed Central

Sanyal, Tanmay; Kaviraj, Anilava; Saha, Subrata

2014-01-01

Accumulation of chromium (Cr) was determined in water, sediment, aquatic plants, invertebrates and fish in aquatic ecosystems receiving effluents from handloom textile industries in Ranaghat–Fulia region of West Bengal in India. Cr was determined in the samples by atomic absorption spectrophotometer and data were analyzed functionally by Genetic Algorithm to determine trend of depositions of Cr in the sediment and water. Area plot curve was used to represent accumulation of Cr in biota. The results indicate that the aquatic ecosystems receiving the effluents from handloom textile factories are heavily contaminated by Cr. The contamination is hardly reflected in the concentration of Cr in water, but sediment exhibits seasonal fluctuation in deposition of Cr, concentration reaching to as high as 451.0 μg g−1 during the peak production period. There is a clear trend of gradual increase in the deposition of Cr in the sediment. Aquatic weed, insect and mollusk specimens collected from both closed water bodies (S1 & S2) and riverine resources (S3 & S4) showed high rate of accumulation of Cr. Maximum concentration of Cr was detected in roots of aquatic weeds (877.5 μg g−1). Fish specimens collected from the polluted sites (S3 & S4) of river Churni showed moderate to high concentration of Cr in different tissues. Maximum concentration was detected in the liver of Glossogobius giuris (679.7 μg g−1) during monsoon followed by gill of Mystus bleekeri (190.0 μg g−1) and gut of G. giuris (123.7 μg g−1) during summer. Eutropiichthys vacha showed moderately high concentration of Cr in different tissues (65–99 μg g−1) while Puntius sarana showed relatively low concentration of Cr (below detection limit to 18.0 μg g−1) in different tissues except in gill (64.4 μg g−1). PMID:26644938

Occurrence of nitrate and pesticides in ground water beneath three agricultural land-use settings in the eastern San Joaquin Valley, California, 1993-1995

USGS Publications Warehouse

Burow, Karen R.; Shelton, Jennifer L.; Dubrovsky, Neil M.

1998-01-01

The processes that affect nitrate and pesticide occurrence may be better understood by relating ground-water quality to natural and human factors in the context of distinct, regionally extensive, land- use settings. This study assesses nitrate and pesticide occurrence in ground water beneath three agricultural land-use settings in the eastern San Joaquin Valley, California. Water samples were collected from 60 domestic wells in vineyard, almond, and a crop grouping of corn, alfalfa, and vegetable land-use settings. Each well was sampled once during 1993?1995. This study is one element of the U.S. Geological Survey?s National Water-Quality Assessment Program, which is designed to assess the status of, and trends in, the quality of the nation?s ground- and surface-water resources and to link the status and trends with an understanding of the natural and human factors that affect the quality of water. The concentrations and occurrence of nitrate and pesticides in ground-water samples from domestic wells in the eastern alluvial fan physiographic region were related to differences in chemical applica- tions and to the physical and biogeochemical processes that charac- terize each of the three land-use settings. Ground water beneath the vineyard and almond land-use settings on the coarse-grained, upper and middle parts of the alluvial fans is more vulnerable to nonpoint- source agricultural contamination than is the ground water beneath the corn, alfalfa, and vegetable land-use setting on the lower part of the fans, near the basin physiographic region. Nitrate concentrations ranged from less than 0.05 to 55 milligrams per liter, as nitrogen. Nitrate concentrations were significantly higher in the almond land-use setting than in the vineyard land-use setting, whereas concentrations in the corn, alfalfa, and vegetable land-use setting were intermediate. Nitrate concentrations exceeded the maximum contaminant level in eight samples from the almond land- use setting (40 percent), in seven samples from the corn, alfalfa, and vegetable land-use setting (35 percent), and in three samples from the vineyard land-use setting (15 percent). The physical and chemical characteristics of the vineyard and the almond land-use settings are similar, characterized by coarse-grained sediments and high dissolved- oxygen concentrations, reflecting processes that promote rapid infiltration of water and solutes. The high nitrate concentrations in the almond land-use setting reflect the high amount of nitrogen appli- cations in this setting, whereas the low nitrate concentrations in the vineyard land-use setting reflect relatively low nitrogen applications. In the corn, alfalfa, and vegetable land-use setting, the relatively fine-grained sediments, and low dissolved-oxygen concentrations, reflect processes that result in slow infiltration rates and longer ground-water residence times. The intermediate nitrate concentrations in the corn, alfalfa, and vegetable land-use setting are a result of these physical and chemical characteristics, combined with generally high (but variable) nitrogen applications. Twenty-three different pesticides were detected in 41 of 60 ground- water samples (68 percent). Eighty percent of the ground-water samples from the vineyard land-use setting had at least one pesticide detection, followed by 70 percent in the almond land-use setting, and 55 percent in the corn, alfalfa, and vegetable land-use setting. All concentra- tions were less than state or federal maximum contaminant levels only 5 of the detected pesticides have established maximum contaminant levels) with the exception of 1,2-dibromo-3-chloropropane, which exceeded the maximum contaminant level of 0.2 micrograms per liter in 10 ground-water samples from vineyard land-use wells and in 5 ground- water samples from almond land-use wells. Simazine was detected most often, occurring in 50 percent of the ground-water samples from the vineyard land-use wells and in 30 percent

Tracking Dissolved Methane Concentrations near Active Seeps and Gas Hydrates: Sea of Japan.

NASA Astrophysics Data System (ADS)

Snyder, G. T.; Aoki, S.; Matsumoto, R.; Tomaru, H.; Owari, S.; Nakajima, R.; Doolittle, D. F.; Brant, B.

2015-12-01

A number of regions in the Sea of Japan are known for active gas venting and for gas hydrate exposures on the sea floor. In this investigation we employed several gas sensors mounted on a ROV in order to determine the concentrations of dissolved methane in the water near these sites. Methane concentrations were determined during two-second intervals throughout each ROV deployment during the cruise. The methane sensor deployments were coupled with seawater sampling using Niskin bottles. Dissolved gas concentrations were later measured using gas chromatography in order to compare with the sensor results taken at the same time. The observed maximum dissolved methane concentrations were much lower than saturation values, even when the ROV manipulators were in contact with gas hydrate. Nonetheless, dissolved concentrations did reach several thousands of nmol/L near gas hydrate exposures and gas bubbles, more than two orders of magnitude over the instrumental detection limits. Most of the sensors tested were able to detect dissolved methane concentrations as low as 10 nmol/L which permitted detection when the ROV approached methane plume sites, even from several tens of meters above the sea floor. Despite the low detection limits, the methane sensors showed variable response times when returning to low-background seawater (~5nM). For some of the sensors, the response time necessary to return to background values occurred in a matter of minutes, while for others it took several hours. Response time, as well as detection limit, should be an important consideration when selecting methane sensors for ROV or AUV investigations. This research was made possible, in part, through funding provided by the Japanese Ministry of Economy, Trade and Industry (METI).

Trace elements and organic chemicals in stream-bottom sediments and fish tissues, Red River of the North basin, Minnesota, North Dakota, and South Dakota, 1992-95

USGS Publications Warehouse

Brigham, M.E.; Goldstein, R.M.; Tornes, L.H.

1998-01-01

Stream-bottom sediment and fish-tissue samples from the Red River of the North Basin, were analyzed for a large suite of chemical elements and organic chemicals. Cadmium, lead, and mercury were widespread in sediments, at concentrations not indicative of acute contamination. Mercury, the element of greatest health concern in the region, was detected at low concentrations in 38 of 43 sediment samples (<0.02-0.13 micrograms per gram) and all of eleven fish-liver samples (0.03-0.6 micrograms per gram dry weight, or 0.0066-0.13 micrograms per gram wet weight). Concentrations of many elements appeared to be controlled by mineral rather than anthropogenic sources. DDT and its metabolites were the most frequently detected synthetic organochlorines: p,p'-DDE was detected in 9 of 38 sediment samples (concentration range: <1-16 nanograms per gram) and also frequently in whole-fish samples. Total DDT (the sum of DDT and its metabolites) concentrations ranged from <5 to 217 nanograms per gram, and at least one component of total DDT was detected in 19 of 23 fish samples. Concentrations of DDT and its metabolites in stream sediments were significantly higher in the intensively cropped Red River Valley Lake Plain, compared to upland areas, probably because of greater historical DDT usage in the lake plain. Several polycyclic aromatic hydrocarbons were detected in stream-bottom sediments. Although the potentially toxic chemicals measured in this study were at low levels, relative to more contaminated areas of the Nation, maximum concentrations of some chemicals are of concern because of their possible effects on aquatic biota and human health.

Accumulation of steroid hormones in soil and its adjacent aquatic environment from a typical intensive vegetable cultivation of North China.

PubMed

Zhang, Feng-Song; Xie, Yun-Feng; Li, Xue-Wen; Wang, Dai-Yi; Yang, Lin-Sheng; Nie, Zhi-Qiang

2015-12-15

Steroid hormones released from manure agricultural application are a matter of global concern. The residual levels of steroid hormones were studied in a typical intensive vegetable cultivation area in northeast China, with a long history of heavy manure application. Seven steroids (estrone, 17α-estradiol, 17β-estradiol, estriol, testosterone, androstendione and progesterone) were analyzed from soil sampled from vegetable greenhouses, from sediments and water from the adjacent drainage ditch and from the groundwater. The results showed that target steroids were detected in the soil samples, with detection frequencies varying from 3.13 to 100%. The steroid concentrations varied substantially in soils, ranging from below the detection limit to 109.7μg·kg(-1). Three steroids-progesterone, androstendione and estrone-were found to have relatively high residue concentrations in soil, with maximum concentrations of 109.7, 9.83 and 13.30μg·kg(-1), respectively. In adjacent groundwater, all the steroids, with the exception of estrone, were detected in one or more of the 13 groundwater samples. The concentrations of steroids in groundwater ranged from below the method detection limit to 2.38ng·L(-1). Six of the seven (excluding androstendione) were detected in drainage ditch water samples, with concentrations ranging from below the detection limit to 14ng·L(-1). Progesterone, androstendione and estrone accumulated relatively easily in soils; their concentrations in groundwater were lower than those of other steroids. The concentrations of testosterone and estriol were relatively low in soil, while in groundwater were higher than those of other steroids. The residual levels of steroids in soil and groundwater showed a clear spatial variation in the study area. The residual levels of steroid hormones in soil varied substantially between differently planted greenhouses. Copyright © 2015. Published by Elsevier B.V.

Detection and identification of plasma progesterone metabolites in the female Florida manatee (Trichechus manatus latirostris) using GC/MS/MS.

PubMed

Tripp, K M; Dubois, M; Delahaut, P; Verstegen, J P

2009-08-01

Florida manatees (Trichechus manatus latirostris) have relatively low peripheral concentrations of progesterone (P4). The objective of this study was to determine if these relatively low P4 concentrations are associated with a high ratio of progestin metabolites and to document metabolite concentrations from individual blood samples obtained from manatees during diestrus or pregnancy. Metabolites known to exist in elephants-terrestrial manatee relatives-were targeted. These included 5alpha-reduced progestins (5alpha-pregnane-3,20-dione [5alpha-DHP] and 3alpha-hydroxy-5alpha-pregnan-20-one [5alpha-P3-OH]) and 17alpha-hydroxyprogesterone (17alpha-OHP), which occurs in Asian elephants. An additional, inactive metabolite, 20alpha-hydroxyprogesterone (20alpha-OHP), indicative of P4 overproduction, was also targeted. Progesterone itself was the predominant progestin detected in pregnant and nonpregnant manatee plasma (n = 10) using gas chromatography-mass spectrometry with tandem quadrupole detectors (GC/MS/MS). Progesterone concentrations in pregnant females varied from early (moderate to high) through mid and late (low) pregnancy. Progesterone concentrations ranged from low to high in nonpregnant, nonlactating females. The most commonly detected metabolite was 5alpha-P3-OH (n = 7), which occurred in pregnant (lower limit of detection [LLOD] to high) and nonpregnant (trace to high) females. The 5alpha-DHP metabolite was also detected in pregnant (LLOD to moderate) and nonpregnant (low) females. The 17alpha-OHP metabolite was not detected in any tested female. The 20alpha-OHP metabolite was detected in one nonpregnant, nonlactating, captive female (LLOD). Metabolites were most prevalent during early pregnancy, concurrent with maximum P4 concentrations. Based on their concentrations in peripheral circulation, we inferred that these metabolites may have, opposite to elephants, a limited physiologic role during luteal, pregnant, and nonpregnant phases in the manatee.

Identification and temporal decrease of 137Cs and 134Cs in groundwater in Minami-Soma City following the accident at the Fukushima Dai-ichi nuclear power plant.

PubMed

Shizuma, Kiyoshi; Fujikawa, Yoko; Kurihara, Momo; Sakurai, Yushi

2018-03-01

The Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident on March 11, 2011, caused severe radioactive contamination in Fukushima Prefecture. In order to clarify the safety of drinking water, we have conducted radiocesium monitoring of public tap water and groundwater in Minami-Soma City, which is 10-40 km north of the nuclear power plant. The source of tap water for Minami-Soma City is groundwater, which is treated by rapid filtration before distribution in two of the three treatment plants. The tap water was collected from six stations during 2012-2016 and groundwater was collected from 11 stations with wells between 5 and 100 m deep during 2014-2016. Radiocesium contamination of groundwater has been considered unlikely in Japan because of the small vertical migration velocity of radiocesium in Japanese soil. However, radiocesium was detected in public tap water after 2012, and the maximum 137 Cs concentration of 292 mBq L -1 was observed in 2013. In all the well water, radiocesium was detected between 2014 and 2015, at concentrations similar to those observed in tap water in the same period. In tap water and groundwater, radiocesium was decreased to below the detection limit in 2016 except for four stations. Radiocesium concentration in shallow water reached a maximum between 2013 and 2015, 2-4 years after the FDNPP accident, and then decreased. The results are interpreted that dissolved 137 Cs migrated in the soil and reached aquifers of various depth. Copyright © 2017 Elsevier Ltd. All rights reserved.

Tritium recapture behavior at a nuclear power reactor due to airborne releases.

PubMed

Harris, Jason T; Miller, David W; Foster, Doug W

2008-08-01

This paper describes the initiatives taken by Cook Nuclear Plant to study the on-site behavior of recaptured tritium released in its airborne effluents. Recapture is the process where a released radioactive effluent, in this case tritium, is brought back on-site through some mechanism. Precipitation, shifts in wind direction, or anthropogenic structures that restrict or alter effluent movement can all lead to recapture. The investigation was started after tritium was detected in the north storm drain outfall. Recent inadvertent tritium releases by several other nuclear power plants, many of which entered the groundwater, have led to increased surveillance and scrutiny by regulatory authorities and the general public. To determine the source of tritium in the outfall, an on-site surface water, well water, rainwater and air-conditioning condensate monitoring program was begun. Washout coefficients were also determined to compare with results reported by other nuclear power plants. Program monitoring revealed detectable tritium concentrations in several precipitation sample locations downwind of the two monitored containment building release vents. Tritium was found in higher concentrations in air-conditioning condensate, with a mean value of 528 Bq L(-1) (14,300 pCi L(-1)). The condensate, and to a lesser extent rainwater, were contributing to the tritium found in the north storm drain outfall. Maximum concentration values for each sample type were used to estimate the most conservative dose. A maximum dose of 1.1 x 10(-10) mSv (1.1 x 10(-8) mrem) total body was calculated to determine the health impact of the tritium detected.

Event-driven time-optimal control for a class of discontinuous bioreactors.

PubMed

Moreno, Jaime A; Betancur, Manuel J; Buitrón, Germán; Moreno-Andrade, Iván

2006-07-05

Discontinuous bioreactors may be further optimized for processing inhibitory substrates using a convenient fed-batch mode. To do so the filling rate must be controlled in such a way as to push the reaction rate to its maximum value, by increasing the substrate concentration just up to the point where inhibition begins. However, an exact optimal controller requires measuring several variables (e.g., substrate concentrations in the feed and in the tank) and also good model knowledge (e.g., yield and kinetic parameters), requirements rarely satisfied in real applications. An environmentally important case, that exemplifies all these handicaps, is toxicant wastewater treatment. There the lack of online practical pollutant sensors may allow unforeseen high shock loads to be fed to the bioreactor, causing biomass inhibition that slows down the treatment process and, in extreme cases, even renders the biological process useless. In this work an event-driven time-optimal control (ED-TOC) is proposed to circumvent these limitations. We show how to detect a "there is inhibition" event by using some computable function of the available measurements. This event drives the ED-TOC to stop the filling. Later, by detecting the symmetric event, "there is no inhibition," the ED-TOC may restart the filling. A fill-react cycling then maintains the process safely hovering near its maximum reaction rate, allowing a robust and practically time-optimal operation of the bioreactor. An experimental study case of a wastewater treatment process application is presented. There the dissolved oxygen concentration was used to detect the events needed to drive the controller. (c) 2006 Wiley Periodicals, Inc.

Preliminary Assessment of Legacy and Current-Use Pesticides in Franciscana Dolphins from Argentina.

PubMed

Romero, M B; Polizzi, P; Chiodi, L; Medici, S; Blando, M; Gerpe, M

2018-06-01

The change towards intensive agriculture has led to an increase in the use of pesticides. In addition, legacy pesticides, such as organochlorines are still present in the environment. Ten Franciscana dolphins were accidentally killed by netting in a coastal area of Argentina in Buenos Aires province. From these animals, organochlorine, organophosphate and pyrethroid pesticides were analyzed in liver, bubbler and melon tissues. The concentrations of Σendosulfan ranged from not detectable values (nd) to 3539 ng g -1 lw, with the maximum level in melon tissue. DDE was present in 60% of all samples at concentrations from nd to 6672 ng g -1 lw, indicating historical DDT contamination. The presence of endosulfan and heptachlor in a nursling calf indicated a transfer of these pesticides through lactational and placental transport. The concentrations of organophosphates and pyrethroids were below the limit of detection, reflecting the low persistence of these compounds.

Occurrence of Veterinary Antibiotics in Swine Manure from Large-scale Feedlots in Zhejiang Province, China.

PubMed

Wang, Hua; Chu, Yixuan; Fang, Chengran

2017-04-01

The occurrence and distribution of five sulfonamides and three tetracyclines in swine manure sampled from large-scale feedlots in different areas of Zhejiang Province, China were detected using solid-phase extraction and high-performance liquid chromatography. All eight test antibiotics were detected in most of the manure samples. The dominant antibiotics in swine manure were sulfadiazine, sulfamerazine, sulfadimidine, tetracycline, and chlortetracycline. The maximum concentration of residual antibiotic reached up to 57.95 mg/kg (chlortetracycline). The concentrations and distribution of both types of antibiotics in swine manure of different areas varied greatly. Relatively higher concentrations of sulfonamides were found in swine manure from the Zhejiang area in this experiment compared with previous studies. The results revealed that antibiotics were extensively used in feedlots in this district and that animal manure might act as a non-specific source of antibiotic residues in farmlands and aquatic environments.

Methamphetamine and Amphetamine Isomer Concentrations in Human Urine Following Controlled Vicks VapoInhaler Administration

PubMed Central

Smith, Michael L.; Nichols, Daniel C.; Underwood, Paula; Fuller, Zachary; Moser, Matthew A.; Flegel, Ron; Gorelick, David A.; Newmeyer, Matthew N.; Concheiro, Marta; Huestis, Marilyn A.

2014-01-01

Legitimate use of legal intranasal decongestants containing l-methamphetamine may complicate interpretation of urine drug tests positive for amphetamines. Our study hypotheses were that commonly used immunoassays would produce no false-positive results and a recently developed enantiomer-specific gas chromatography–mass spectrometry (GC–MS) procedure would find no d-amphetamine or d-methamphetamine in urine following controlled Vicks VapoInhaler administration at manufacturer's recommended doses. To evaluate these hypotheses, 22 healthy adults were each administered one dose (two inhalations in each nostril) of a Vicks VapoInhaler every 2 h for 10 h on Day 1 (six doses), followed by a single dose on Day 2. Every urine specimen was collected as an individual void for 32 h after the first dose and assayed for d- and l-amphetamines specific isomers with a GC–MS method with >99% purity of R-(−)-α-methoxy-α-(trifluoromethyl)phenylacetyl derivatives and 10 µg/L lower limits of quantification. No d-methamphetamine or d-amphetamine was detected in any urine specimen by GC–MS. The median l-methamphetamine maximum concentration was 62.8 µg/L (range: 11.0–1,440). Only two subjects had detectable l-amphetamine, with maximum concentrations coinciding with l-methamphetamine peak levels, and always ≤4% of the parent's maximum. Three commercial immunoassays for amphetamines EMIT® II Plus, KIMS® II and DRI® had sensitivities, specificities and efficiencies of 100, 97.8, 97.8; 100, 99.6, 99.6 and 100, 100, 100%, respectively. The immunoassays had high efficiencies, but our first hypothesis was not affirmed. The EMIT® II Plus assay produced 2.2% false-positive results, requiring an enantiomer-specific confirmation. PMID:25217541

Occurrence and removal of progestagens in two representative swine farms: Effectiveness of lagoon and digester treatment.

PubMed

Liu, Shuang-Shuang; Ying, Guang-Guo; Liu, You-Sheng; Yang, Yuan-Yuan; He, Liang-Ying; Chen, Jun; Liu, Wang-Rong; Zhao, Jian-Liang

2015-06-15

A total of 21 progestagens were screened in animal wastes and environmental samples from two representative swine farms and surrounding environments of South China using ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) to assess the effectiveness of simple lagoon (and digester) treatment. The results showed that 11, 8 and 8 of 21 target progestagens were detected with the minimum concentration of 2.31 ng/L and maximum of 6150 ng/L in the water samples, with the minimum of 1.36 ng/L and maximum of 98.3 ng/L in the suspended particles, and with the minimum of 1.57 ng/g dry weight (dw) and maximum of 3310 ng/g dw in the solid samples, respectively. Trace levels (a few ng/L or ng/g levels) of dydrogesterone, 5α-dihydroprogesterone, norgestrel and progesterone were found in samples from nearby surface waters and vegetable fields impacted by animal wastes. The residual progestagens at the reported levels may still pose potential risks to aquatic organisms such as fish in the receiving aquatic environments. This finding suggests that swine wastewater and feces could lead to contamination of some detectable progestagens in the surrounding environments. Significant reduction in total progestagen concentrations were observed from the fresh swine wastewaters to the fish ponds, indicating effective removal of these compounds by the lagoon (and digester) treatment. In addition, the biogas digesters provided high removal of the progestagens in the waste streams. This low-cost and eco-friendly treatment system should be promoted in developing countries with concentrated animal operations. Copyright © 2015 Elsevier Ltd. All rights reserved.

Surface-water-quality assessment of the upper Illinois River Basin in Illinois, Indiana, and Wisconsin; pesticides and other synthetic organic compounds in water, sediment, and biota, 1975-90

USGS Publications Warehouse

Sullivan, Daniel J.; Stinson, Troy W.; Crawford, J. Kent; Schmidt, Arthur R.; Colman, John A.

1998-01-01

The distribution of pesticides and other synthetic organic compounds in water, sediment, and biota in the upper Illinois River Basin in Illinois, Indiana, and Wisconsin was examined from 1987 through 1990 as part of the pilot National Water-Quality Assesssment Program conducted by the U.S. Geological Survey. Historical data for water and sediment collected from 1975 through 1986 were similar to data collected from 1987 through 1990. Some compounds were detected in concentrations that exceed U.S. Environmental Protection Agency water-quality criteria. Results from pesticide sampling at four stations in 1988 and 1989 identified several agricultural pesticides that were detected more frequently and at higher concentrations in urban areas than in agricultural areas. Results from herbicide sampling at 17 stations in the Kankakee and Iroquois River Basins in 1990 indicated that atrazine concentrations exceeded the U.S. Environmental Protection Agency's maximum contaminant level for drinking water during runoff periods. Results from sampling for volatile and semivolatile organic compounds in water indicate that, with one exception, all stations at which more than one compound was detected were within 2 miles downstream from the nearest point source. Detections at two stations in the Chicago urban area accounted for 37 percent of the total number of detections. Concentrations of tetrachloroethylene, trichloroethylene, and 1,2-dichlorethane from stations in the Des Plaines River Basin exceeded the U.S. Environmental Protection Agency's maximum contaminant level for drinking water in one and two samples from the two stations in the Chicago area. Phenols and pentachlorophenols were detected most frequently in the Des Plaines River Basin where point-source discharges were common. Phenol concentrations were significantly different among the Des Plaines, Kankakee, and Fox River Basins. Phenols and pentachlorophenols never exceeded the general use and secondary contact standards. Results from a 1989 synoptic survey of semivolatile organic compounds in sediment indicate that these compounds were detected most frequently at sites in the Chicago urban area. Of the 17 stations at which 10 or more compounds were detected, 14 were located in the Des Plaines River subbasin, and 1 was on the Illinois River mainstem. As was the case with organic compounds in water, each of these sites was located within 2 miles downstream from point sources. Biota samples were collected and analyzed for organochlorines and polynuclear aromatic hydrocarbons in 1989 and 1990. The most commonly detected compound in both years was p,p'-DDE. National Academy of Science recommendations for chlordane and dieldrin for protection of predators were exceeded in 19 and 10 samples, respectively, when the 1989 and 1990 data were combined. In the nine fish-fillet samples collected in 1989, concentrations exceeded U.S. Environmental Protection Agency fish-tissue criteria in nine fillets for p,p'-DDE and five fillets for dieldrin.

Ground-water sampling methods and quality-control data for the Red River of the North basin, Minnesota, North Dakota, and South Dakota, 1993-95

USGS Publications Warehouse

Menheer, M.A.; Brigham, M.E.

1997-01-01

Quality-control data demonstrated that most constituents measured for this study yielded reproducible data, with low to undetectable contamination from the sampling and analytical procedures. Several constituents were occasionally or frequently detected in blank samples at levels similar to low-concentration ground-water-quality samples. For example, iron was detected in 75 percent of the blank samples, with a maximum concentration of 27 [ig/L, indicating that iron contamination may interfere with its determination at low levels in ground waters. Copper, aluminum, and dissolved organic carbon concentrations in blank samples overlap those determined in ground-waterquality samples, thereby precluding quantitative reporting of those constituents. Most pesticide data are reproducible, with minimal bias. Some pesticides had low but consistent recoveries; these data may be useful if spike and surrogate data are carefully considered. Data for some pesticides measured in this study should not be quantitatively reported or used, because they may underestimate the concentrations of those pesticides in ground waters.

Open-path in situ measurement of the nitrate radical concentrations during the CAREBeijing-NCP 2014 summer campaign

NASA Astrophysics Data System (ADS)

George, Midhun; Suhail, Suhail; Chandran, Satheesh; Chen, Jun; Lu, Keding; Ruth, Albert; Venables, Dean; Varma, Ravi

2016-04-01

We describe the application of an incoherent broadband cavity-enhanced absorption spectrometer in an open path configuration (OP-IBBCEAS) for in situ detection of nitrate radical (NO3) and aerosol extinction. The optical cavity was 3.35 m long with separate transmitter and receiver units, and the instrument was installed on top of a residential complex (elevation of 17 m) near the CAREBEIJING-NCP 2014 supersite in Wangdu, 200 km southwest of Beijing. Despite high aerosol loading, NO3 was detected on all nights when the instrument was operational (28-30 June, 2014). The maximum concentration measured was 170 pptv with a detection limit of 40 pptv for measurements. Preliminary quantification of the aerosol extinction is also described. The results presented here demonstrate the sensitivity and specificity that can be achieved from open path measurements and its application to polluted environments.

Hydrochemical and microbiological quality of groundwater in West Thrace Region of Turkey

NASA Astrophysics Data System (ADS)

Özler, H. Murat; Aydın, Ali

2008-03-01

The aim of this study was to do a preliminary assessment of the hydrochemical and microbial groundwater quality of the West Thrace region. Forty samples of groundwater collected from Edirne (Site 1) to Gelibolu (Site 2) were assessed for their suitability for human consumption. As3- was non-detectable in all the groundwater and Zn2+, Pb2+, F-, Cu2+, NH{4/+}, Cn- PO{4/3-} and Cl- were all below their respective European Union drinking water directive (EU-DWD) and Turkish food codex-drinking water directive (TFC-DWD). Maximum Acceptable Concentrations (MAC) Ni2+, Pb2+, Cd2+, Mg2+, Mn2+, and Ca2+ levels were detected in upper maximum acceptable concentrations 77.5, 42.5, 35.0, 50.0, 50.0, and 32.5% of the groundwater samples, respectively. However, in terms of Cr3+, Ni2+ and Pb2+, the differences between groundwaters of Sites 1 and 2 were significant ( p < 0.05). Eight water samples (20%) had HPC exceeding the EU and Turkish water directive limit 20 CFU (Colony Forming Unit)/ml in drinking water and the maximum bacteria count recorded was 44 CFU/ml. Total coliforms, thermotolerant coliforms, E. coli, Enterococcus spp., Salmonella sp., Staphylococcus spp. and P. aeruginosa were detected in 25, 17.5, 15, 47.5, 15, 27.5, and 15% of the groundwater samples, respectively. Furthermore, heavy metals and trace elements were found after chemical analyzes in most samples. The pollution of groundwater come from a variety of sources, Meric and Ergene rivers, including land application of agricultural chemicals and organics wastes, infiltration of irrigation water, septic tanks, and infiltration of effluent from sewage treatment plants, pits, lagoons and ponds used storage.

High frequency monitoring of pesticides in runoff water to improve understanding of their transport and environmental impacts.

PubMed

Lefrancq, Marie; Jadas-Hécart, Alain; La Jeunesse, Isabelle; Landry, David; Payraudeau, Sylvain

2017-06-01

Rainfall-induced peaks in pesticide concentrations can occur rapidly. Low frequency sampling may therefore largely underestimate maximum pesticide concentrations and fluxes. Detailed storm-based sampling of pesticide concentrations in runoff water to better predict pesticide sources, transport pathways and toxicity within the headwater catchments is lacking. High frequency monitoring (2min) of seven pesticides (Dimetomorph, Fluopicolide, Glyphosate, Iprovalicarb, Tebuconazole, Tetraconazole and Triadimenol) and one degradation product (AMPA) were assessed for 20 runoff events from 2009 to 2012 at the outlet of a vineyard catchment in the Layon catchment in France. The maximum pesticide concentrations were 387μgL -1 . Samples from all of the runoff events exceeded the legal limit of 0.1μgL -1 for at least one pesticide (European directive 2013/39/EC). High resolution sampling used to detect the peak pesticide levels revealed that Toxic Units (TU) for algae, invertebrates and fish often exceeded the European Uniform principles (25%). The point and average (time or discharge-weighted) concentrations indicated up to a 30- or 4-fold underestimation of the TU obtained when measuring the maximum concentrations, respectively. This highlights the important role of sampling methods for assessing peak exposure. High resolution sampling combined with concentration-discharge hysteresis analyses revealed that clockwise responses were predominant (52%), indicating that Hortonian runoff is the prevailing surface runoff trigger mechanism in the study catchment. The hysteresis patterns for suspended solids and pesticides were highly dynamic and storm- and chemical-dependent. Intense rainfall events induced stronger C-Q hysteresis (magnitude). This study provides new insights into the complexity of pesticide dynamics in runoff water and highlights the ability of hysteresis analysis to improve understanding of pesticide supply and transport. Copyright © 2017 Elsevier B.V. All rights reserved.

Characteristics of water, sediment, and benthic communities of the Wolf River, Menominee Indian Reservation, Wisconsin, water years 1986-98

USGS Publications Warehouse

Garn, Herbert S.; Scudder, Barbara C.; Richards, Kevin D.; Sullivan, Daniel J.

2001-01-01

Analyses and interpretation of water quality, sediment, and biological data from water years 1986 through 1998 indicated that land use and other human activities have had only minimal effects on water quality in the Wolf River upstream from and within the Menominee Indian Reservation in northeastern Wisconsin. Relatively high concentrations of calcium and magnesium (natural hardness), iron, manganese, and aluminum were measured in Wolf River water samples during water years 1986?98 from the three sampled sites and attributed to presence of highly mineralized geologic materials in the basin. Average calcium and magnesium concentrations varied from 22?26 milligrams per liter (mg/L) and 11?13 mg/L, respectively. Average iron concentrations ranged from 290?380 micrograms per liter (?g/L); average manganese concentrations ranged from 53?56 mg/L. Average aluminum concentrations ranged from 63?67 ?g/L. Mercury was present in water samples but concentrations were not at levels of concern. Levels of Kjeldahl nitrogen, ammonia, nitrite plus nitrate, total phosphorus, and orthophosphorus in water samples were often low or below detection limits (0.01? 0.10 mg/L). Trace amounts of atrazine (maximum concentration of 0.031 ?g/L), deethylatrazine (maximum 0.032 ?g/L), and alachlor (maximum of 0.002 ?g/L) were detected. Low concentrations of most trace elements were found in streambed sediment. Tissues of fish and aquatic invertebrates collected once each year from 1995 through 1998 at the Langlade and Keshena sites, near the northern and southern boundaries of the Reservation, respectively, were low in concentrations of most trace elements. Arsenic and silver in fish livers from both sites were less than or equal to 2 ?g/g arsenic and less than 1 ?g/g silver for dry weight analysis, and concentrations of antimony, beryllium, cadmium, cobalt, lead, nickel, and uranium were all below detection limits (less than 1 ?g/g dry weight). Concentrations of most other trace elements in fish were low, with the exceptions of chromium, copper, mercury, and selenium; however, these concentrations are not at levels of concern. Concentrations of all trace elements analyzed in whole caddisfly larvae also were low compared to those reported in the literature. During 1998, a total of 48 species of macroinvertebrates were identified at each of two sampled sites, with similar numbers of genera represented at both: 41 at Keshena and 44 at Langlade. The percentage EPT (Ephemeroptera, Plecoptera, and Trichoptera) was 52 at Keshena and 77 at Langlade; these relatively large percentages suggest very good to excellent water quality at these sites. A total of 52 algal taxa were identified at the Wolf River near Langlade. Diatoms made up 96 percent of the algal biomass. A total of 58 algal taxa were identified at Keshena, including 48 diatom taxa (83 percent). Although diatoms accounted for just 22 percent of the algal relative abundance, in cells per square centimeter, diatoms contributed 91 percent of the total algal biomass. The overall biological integrity of the Keshena and Langlade sites, based on diversity, siltation, and pollution indexes for diatoms is excellent.

Assessment of a direct hybridization microarray strategy for comprehensive monitoring of genetically modified organisms (GMOs).

PubMed

Turkec, Aydin; Lucas, Stuart J; Karacanli, Burçin; Baykut, Aykut; Yuksel, Hakki

2016-03-01

Detection of GMO material in crop and food samples is the primary step in GMO monitoring and regulation, with the increasing number of GM events in the world market requiring detection solutions with high multiplexing capacity. In this study, we test the suitability of a high-density oligonucleotide microarray platform for direct, quantitative detection of GMOs found in the Turkish feed market. We tested 1830 different 60nt probes designed to cover the GM cassettes from 12 different GM cultivars (3 soya, 9 maize), as well as plant species-specific and contamination controls, and developed a data analysis method aiming to provide maximum throughput and sensitivity. The system was able specifically to identify each cultivar, and in 10/12 cases was sensitive enough to detect GMO DNA at concentrations of ⩽1%. These GMOs could also be quantified using the microarray, as their fluorescence signals increased linearly with GMO concentration. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evaluation and trends of land cover, streamflow, and water quality in the North Canadian River Basin near Oklahoma City, Oklahoma, 1968–2009

USGS Publications Warehouse

Esralew, Rachel A.; Andrews, William J.; Smith, S. Jerrod

2011-01-01

The U.S. Geological Survey, in cooperation with the city of Oklahoma City, collected water-quality samples from the North Canadian River at the streamflow-gaging station near Harrah, Oklahoma (Harrah station), since 1968, and at an upstream streamflow-gaging station at Britton Road at Oklahoma City, Oklahoma (Britton Road station), since 1988. Statistical summaries and frequencies of detection of water-quality constituent data from water samples, and summaries of water-quality constituent data from continuous water-quality monitors are described from the start of monitoring at those stations through 2009. Differences in concentrations between stations and time trends for selected constituents were evaluated to determine the effects of: (1) wastewater effluent discharges, (2) changes in land-cover, (3) changes in streamflow, (4) increases in urban development, and (5) other anthropogenic sources of contamination on water quality in the North Canadian River downstream from Oklahoma City. Land-cover changes between 1992 and 2001 in the basin between the Harrah station and Lake Overholser upstream included an increase in developed/barren land-cover and a decrease in pasture/hay land cover. There were no significant trends in median and greater streamflows at either streamflow-gaging station, but there were significant downward trends in lesser streamflows, especially after 1999, which may have been associated with decreases in precipitation between 1999 and 2009 or construction of low-water dams on the river upstream from Oklahoma City in 1999. Concentrations of dissolved chloride, lead, cadmium, and chlordane most frequently exceeded the Criterion Continuous Concentration (a water-quality standard for protection of aquatic life) in water-quality samples collected at both streamflow-gaging stations. Visual trends in annual frequencies of detection were investigated for selected pesticides with frequencies of detection greater than 10 percent in all water samples collected at both streamflow-gaging stations. Annual frequencies of detection of 2,4-dichlorophenoxyacetic acid and bromacil increased with time. Annual frequencies of detection of atrazine, chlorpyrifos, diazinon, dichlorprop, and lindane decreased with time. Dissolved nitrogen and phosphorus concentrations were significantly greater in water samples collected at the Harrah station than at the Britton Road station, whereas specific conductance was greater at the Britton Road station. Concentrations of dissolved oxygen, biochemical oxygen demand, and fecal coliform bacteria were not significantly different between stations. Daily minimum, mean, and maximum specific conductance collected from continuous water-quality monitors were significantly greater at the Britton Road station than in water samples collected at the Harrah station. Daily minimum, maximum, and diurnal fluctuations of water temperature collected from continuous water-quality monitors were significantly greater at the Harrah station than at the Britton Road station. The daily maximums and diurnal range of dissolved oxygen concentrations were significantly greater in water samples collected at the Britton Road station than at the Harrah station, but daily mean dissolved oxygen concentrations in water at those streamflow-gaging stations were not significantly different. Daily mean and diurnal water temperature ranges increased with time at the Britton Road and Harrah streamflow-gaging stations, whereas daily mean and diurnal specific conductance ranges decreased with time at both streamflow-gaging stations from 1988–2009. Daily minimum dissolved oxygen concentrations collected from continuous water-quality monitors more frequently indicated hypoxic conditions at the Harrah station than at the Britton Road station after 1999. Fecal coliform bacteria counts in water decreased slightly from 1988–2009 at the Britton Road station. The Seasonal Kendall's tau test indicated significant downward trends in

Assessment of concentrations of trace elements in ground water and soil at the Small-Arms Firing Range, Shaw Air Force Base, South Carolina

USGS Publications Warehouse

Landmeyer, J.E.

1994-01-01

Ground-water samples were collected from four shallow water-table aquifer observation wells beneath the Small-Arms Firing Range study area at Shaw Air Force Base. Water-chemistry analyses indicated that total lead concentrations in shallow ground water beneath the study area do not exceed the U.S. Environmental Protection Agency maximum contaminant level established for lead in drinking water (0.05 milligrams per liter). All other trace element total concentrations in ground water beneath the study area were at or below the detection limit of the analytical methodology.

Sprayable enzyme-activatable fluorescent probes: kinetic mapping using dynamic fluorescence imaging can help detecting tiny cancer foci (Conference Presentation)

NASA Astrophysics Data System (ADS)

Kobayashi, Hisataka

2017-02-01

Optical fluorescence-guided imaging is increasingly used to guide surgery and endoscopic procedures. Sprayable enzyme-activatable probes are particularly useful because of high target-to-background ratios that increase sensitivity for tiny cancer foci. However, green fluorescent activatable probes suffers from interference from autofluorescence found in biological tissue. Dynamic imaging followed by the kinetic analysis could be detected local enzyme activity and used to differentiate specific fluorescence arising from an activated probe in a tumor from autofluorescence in background tissues especially when low concentrations of the dye are applied to detect tiny cancer foci. Serial fluorescence imaging was performed using various concentrations of γ-glutamyl hydroxymethyl rhodamine green (gGlu-HMRG) which was sprayed on the peritoneal surface with tiny implants of SHIN3-dsRed ovarian cancer tumors. Temporal differences in signal between specific green fluorescence in cancer foci and non-specific autofluorescence in background tissue was measured and processed into three kinetic maps reflecting maximum fluorescence signal (MF), wash-in rate (WIR), and area under the curve (AUC), respectively. Especially at lower concentrations, kinetic maps derived from dynamic fluorescence imaging were clearly superior to unprocessed images for detection small cancer foci.

Presence and distribution of wastewater-derived pharmaceuticals in soil irrigated with reclaimed water

USGS Publications Warehouse

Kinney, C.A.; Furlong, E.T.; Werner, S.L.; Cahill, J.D.

2006-01-01

Three sites in the Front Range of Colorado, USA, were monitored from May through September 2003 to assess the presence and distribution of pharmaceuticals in soil irrigated with reclaimed water derived from urban wastewater. Soil cores were collected monthly, and 19 pharmaceuticals, all of which were detected during the present study, were measured in 5-cm increments of the 30-cm cores. Samples of reclaimed water were analyzed three times during the study to assess the input of pharmaceuticals. Samples collected before the onset of irrigation in 2003 contained numerous pharmaceuticals, likely resulting from the previous year's irrigation. Several of the selected pharmaceuticals increased in total soil concentration at one or more of the sites. The four most commonly detected pharmaceuticals were erythromycin, carbamazepine, fluoxetine, and diphenhydramine. Typical concentrations of the individual pharmaceuticals observed were low (0.02-15 ??g/kg dry soil). The existence of subsurface maximum concentrations and detectable concentrations at the lowest sampled soil depth might indicate interactions of soil components with pharmaceuticals during leaching through the vadose zone. Nevertheless, the present study demonstrates that reclaimed-water irrigation results in soil pharmaceutical concentrations that vary through the irrigation season and that some compounds persist for months after irrigation. ?? 2006 SETAC.

Pesticide residue determination in vegetables from western China applying gas chromatography with mass spectrometry.

PubMed

Qin, Guofu; Zou, Keting; Li, Yongbo; Chen, Yan; He, Fengrui; Ding, Guirong

2016-09-01

In this study,an effort has been made to evaluate the pesticide residues in vegetables from western China. Fifty-one pesticides, including organophosphorus, organochlorine, carbamate and pyrethroid, were detected in 369 commonly used vegetables by GC-MS. Concentrations of organophosphorus pesticides were detected ranging from 0.0008 to 18.8200 mg/kg, among which organophosphorus pesticide concentrations exceeded their maximum residue levels (MRLs) in five samples. Carbamate and organochlorine pesticides were determined to have concentrations in the range of 0.0012-0.7928 mg/kg. The residual concentrations of carbamate pesticides in six samples and organochlorine pesticides in four samples exceeded their MRLs. The residual concentrations of five pyrethroid pesticides were within the range of 0.0016-6.0827 mg/kg and the pyrethroid residues in two samples exceeded their MRLs. The results revealed that pesticide residues in 70.73% of the vegetables samples were not detected, while in the rest of vegetables there were one or more pesticide residues and some even exceeded their MRLs, which would threaten the health of consumers. Our work provides significant information for the food safety regulations to control the excessive use of some pesticides on those kinds of vegetables from western China. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Spatial distribution of tropospheric ozone in western Washington, USA

USGS Publications Warehouse

Cooper, S.M.; Peterson, D.L.

2000-01-01

We quantified the distribution of tropospheric ozone in topographically complex western Washington state, USA (total area a??6000 km2), using passive ozone samplers along nine river drainages to measure ozone exposure from near sea level to high-elevation mountain sites. Weekly average ozone concentrations were higher with increasing distance from the urban core and at higher elevations, increasing a mean of 1.3 ppbv per 100 m elevation gain for all mountain transects. Weekly average ozone concentrations were generally highest in Cascade Mountains drainages east and southeast of Seattle (maximum=55a??67 pbv) and in the Columbia River Gorge east of Portland (maximum=59 ppbv), and lowest in the western Olympic Peninsula (maximum=34 ppbv). Higher ozone concentrations in the Cascade Mountains and Columbia River locations downwind of large cities indicate that significant quantities of ozone and ozone precursors are being transported eastward toward rural wildland areas by prevailing westerly winds. In addition, temporal (week to week) variation in ozone distribution is synchronous within and between all drainages sampled, which indicates that there is regional coherence in air pollution detectable with weekly averages. These data provide insight on large-scale spatial variation of ozone distribution in western Washington, and will help regulatory agencies optimize future monitoring networks and identify locations where human health and natural resources could be at risk.

Hydrogeology and quality of ground water in the Boone Formation and Cotter Dolomite in karst terrain of northwestern Boone County, Arkansas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leidy, V.A.; Morris, E.E.

1991-01-01

Shallow groundwater flow systems in karst terrain of northwestern Boone County, Arkansas, are particularly susceptible to contamination. The potential for groundwater contamination probably is greater in the northern one-half of the study area where there are more photolineaments and presumably subsurface fractures. Groundwater samples from 17 springs discharging from the Boone Formation and 17 wells completed in the Cotter Dolomite were analyzed to determine ambient groundwater quality and to document water quality variations. The chemical constituents in groundwater generally did not exceed US Environmental Protection Agency primary or secondary maximum contaminant levels. However, fecal coliform and fecal streptococcus bacteria weremore » detected in most springs and in three wells. One spring, located near an abandoned wood-treatment plant (a designated Superfund site), had maximum iron, manganese, lead, and pentachlorophenol concentration that exceeded US Environmental Protection Agency's primary or secondary maximum contamination levels for drinking water. Water samples collected from selected springs emerging from the Boone Formation exhibited an overall decrease in specific conductance and total alkalinity, calcium, magnesium, sodium, and chloride concentrations and an overall increase in nitrate, fecal coliform, and fecal streptococcus bacteria concentrations 3 to 8 hours after a rainstorm.« less

Shallow ground-water quality beneath rice areas in the Sacramento Valley, California, 1997

USGS Publications Warehouse

Dawson, Barbara J.

2001-01-01

In 1997, the U.S. Geological Survey installed and sampled 28 wells in rice areas in the Sacramento Valley as part of the National Water-Quality Assessment Program. The purpose of the study was to assess the shallow ground-water quality and to determine whether any effects on water quality could be related to human activities and particularly rice agriculture. The wells installed and sampled were between 8.8 and 15.2 meters deep, and water levels were between 0.4 and 8.0 meters below land surface. Ground-water samples were analyzed for 6 field measurements, 29 inorganic constituents, 6 nutrient constituents, dissolved organic carbon, 86 pesticides, tritium (hydrogen- 3), deuterium (hydrogen-2), and oxygen-18. At least one health-related state or federal drinking-water standard (maximum contaminant or long-term health advisory level) was exceeded in 25 percent of the wells for barium, boron, cadmium, molybdenum, or sulfate. At least one state or federal secondary maximum contaminant level was exceeded in 79 percent of the wells for chloride, iron, manganese, specific conductance, or dissolved solids. Nitrate and nitrite were detected at concentrations below state and federal 2000 drinking-water standards; three wells had nitrate concentrations greater than 3 milligrams per liter, a level that may indicate impact from human activities. Ground-water redox conditions were anoxic in 26 out of 28 wells sampled (93 percent). Eleven pesticides and one pesticide degradation product were detected in ground-water samples. Four of the detected pesticides are or have been used on rice crops in the Sacramento Valley (bentazon, carbofuran, molinate, and thiobencarb). Pesticides were detected in 89 percent of the wells sampled, and rice pesticides were detected in 82 percent of the wells sampled. The most frequently detected pesticide was the rice herbicide bentazon, detected in 20 out of 28 wells (71 percent); the other pesticides detected have been used for rice, agricultural, and non-agricultural purposes. All pesticide concentrations were below state and federal 2000 drinking-water standards. The relation of the ground-water quality to natural processes and human activities was tested using statistical methods (Spearman rank correlation, Kruskal?Wallis, or rank-sum tests) to determine whether an influence from rice land-use or other human activities on ground-water chemistry could be identified. The detection of pesticides in 89 percent of the wells sampled indicates that human activities have affected shallow ground-water quality. Concentrations of dissolved solids and inorganic constituents that exceeded state or federal 2000 drinking-water standards showed a statistical relation to geomorphic unit. This is interpreted as a relation to natural processes and variations in geology in the Sacramento River Basin; the high concentrations of dissolved solids and most inorganic constituents did not appear to be related to rice land use. No correlation was found between nitrate concentration and pesticide occurrence, indicating that an absence of high nitrate concentrations is not a predictor of an absence of pesticide contamination in areas with reducing ground-water conditions in the Sacramento Valley. Tritium concentrations, pesticide detections, stable isotope data, and dissolved-solids concentrations suggest that shallow ground water in the ricegrowing areas of the Sacramento Valley is a mix of recently recharged ground water containing pesticides, nitrate, and tritium, and unknown sources of water that contains high concentrations of dissolved solids and some inorganic constituents and is enriched in oxygen-18. Evaporation of applied irrigation water, which leaves behind salt, accounts for some of the elevated concentrations of dissolved solids. More work needs to be done to understand the connections between the land surface, shallow ground water, deep ground water, and the drinking-water supplies in the Sacramento Valley.

Nanocomposite polymer structures for optical sensors of hydrogen sulfide

NASA Astrophysics Data System (ADS)

Sergeev, A. A.; Mironenko, A. Yu.; Nazirov, A. E.; Leonov, A. A.; Voznesenskii, S. S.

2017-08-01

Composite coatings based on gold and silver nanoparticles reduced in situ in the film of chitosan polysaccharide are studied. In the presence of hydrogen sulfide, the maximum of plasmon resonance of the nanoparticles that is proportional to the analyte concentration decreases. The detection limits for hydrogen sulfide are 0.1 and 5 ppm for the chitosan/silver and chitosan/gold nanocomposites, respectively.

Fate of vinclozolin, thiabendazole and dimethomorph during storage, handling and forcing of chicory.

PubMed

Spanoghe, Pieter; Ryckaert, Bert; Van Gheluwe, Cindy; Van Labeke, Marie-Christine

2010-02-01

As part of ongoing research for a sustainable production of Belgian endives, the fate of three fungicides during storage, handling and forcing of witloof chicory roots was investigated. Storage roots are protected against Sclerotinia sp. Fuckel and Phoma exigua var. exigua Desm. by means of vinclozolin and thiabendazole respectively. During hydroponic forcing, the most imminent pathogen is Phytophthora cryptogea Pethybr. & Laff., which is controlled by the use of dimethomorph. Vinclozolin and thiabendazole concentrations on roots remained constant during storage at -1 degrees C. Dermal exposure of the workers in hydroponics was exceeded. Vinclozolin and thiabendazole residues were not detected 2 weeks after hydroponic forcing; dimethomorph was still detected at harvest. At harvest, the vinclozolin concentration in the chicory heads was below the maximum residue limit, but the chicory roots contained residues much above the thiabendazole and dimethomorph maximum residue level. Vinclozolin and thiabendazole residues applied before storage are still present on the roots at the start of the forcing cycle. During the set-up of chicory roots, preventive measures are recommended, as effects of repeated human exposure to low doses of applied fungicides cannot be excluded. Dimethomorph applied at the start of the hydroponic forcing is the only pesticide detected in the drainage water at harvest. The chicory heads were safe for human consumption. However, more attention should be paid to the residues of fungicides in the roots used for cattle feeding.

The influence of monovalent cations on trimeric G protein G(i)1α activity in HEK293 cells stably expressing DOR-G(i)1α (Cys(351)-Ile(351)) fusion protein.

PubMed

Vošahlíková, M; Svoboda, P

2011-01-01

The effect of monovalent cations on trimeric G protein G(i)1α was measured at equimolar concentration of chloride anion in pertussis-toxin (PTX)-treated HEK293 cells stably expressing PTX-insensitive DOR- G(i)1α (Cys(351)-Ile(351)) fusion protein by high-affinity [(35)S]GTPgammaS binding assay. The high basal level of binding was detected in absence of DOR agonist and monovalent ions and this high level was inhibited with the order of: Na(+) > K(+) > Li(+). The first significant inhibition was detected at 1 mM NaCl. The inhibition by monovalent ions was reversed by increasing concentrations of DOR agonist DADLE. The maximum DADLE response was also highest for sodium and decreased in the order of: Na(+) > K(+) ~ Li(+). Our data indicate i) an inherently high activity of trimeric G protein G(i)1α when expressed within DOR- G(i)1α fusion protein and determined in the absence of monovalent cations, ii) preferential sensitivity of DOR- G(i)1alpha to sodium as far as maximum of agonist response is involved.

Azinphos-methyl residues in apples and spatial distribution of fluorescein in vase-shaped apple trees.

PubMed

Bélanger, A; Bostanian, N J; Boivin, G; Boudreau, F

1991-06-01

Vase-shaped standard apple trees cv. McIntosh were sprayed with azinphos-methyl at pink, pink and 1st cover and 1st cover only. Residue analyses by gas chromatography revealed detectable residues on foliage until mid summer. At harvest, negligible residue levels were found on the peel and the whole apple. On four trees, fluorescein was sprayed in the same manner as the insecticide and maximum levels of the dye were detected on the outside lower canopy along the row. Minimal concentration of fluorescein was detected on the inner upper canopy away from the direction of the row.

Passive micromixer for luminol-peroxide chemiluminescence detection.

PubMed

Lok, Khoi Seng; Kwok, Yien Chian; Nguyen, Nam-Trung

2011-06-21

This paper reports a microchip with an integrated passive micromixer based on chaotic advection. The micromixer with staggered herringbone structures was used for luminol-peroxide chemiluminescence detection. The micromixer was examined to assess its suitability for chemiluminescence reaction. The relationship between the flow rate and the location of maximum chemiluminescence intensity was investigated. The light intensity was detected using an optical fiber attached along the mixing channel and a photon detector. A linear correlation between chemiluminescence intensity and the concentration of cobalt(ii) ions or hydrogen peroxide was observed. This microchip has a potential application in environmental monitoring for industries involved in heavy metals and in medical diagnostics.

Correlation fluorescence method of amine detection

NASA Astrophysics Data System (ADS)

Myslitsky, Valentin F.; Tkachuk, Svetlana S.; Rudeichuk, Volodimir M.; Strinadko, Miroslav T.; Slyotov, Mikhail M.; Strinadko, Marina M.

1997-12-01

The amines fluorescence spectra stimulated by UV laser radiation are investigated in this paper. The fluorescence is stimulated by the coherent laser beam with the wavelength 0.337 micrometers . At the sufficient energy of laser stimulation the narrow peaks of the fluorescence spectra are detected besides the wide maximum. The relationship between the fluorescence intensity and the concentration of amines solutions are investigated. The fluorescence intensity temporal dependence on wavelength 0.363 micrometers of the norepinephrine solution preliminarily radiated by UV laser with wavelength 0.337 micrometers was found. The computer stimulated and experimental investigations of adrenaline and norepinephrine mixtures fluorescence spectra were done. The correlation fluorescent method of amines detection is proposed.

Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Salton Sea area, California, 1986-87

USGS Publications Warehouse

Setmire, J.G.; Wolfe, J.C.; Stroud, R.K.

1990-01-01

Water, bottom sediment, and biota were sampled during 1986 and 1987 in the Salton Sea area to determine concentrations of trace elements and pesticides as part of the Department of Interior Irrigation Drainage Program. The sampling sites (12 water, 15 bottom sediment, and 5 biota) were located in the Coachella and Imperial Valleys. The focus of sampling was to determine the current or potential threat to the wildlife of the Salton National Wildlife Refuge from irrigation projects sponsored or operated by the Department of the Interior. Results of the investigation indicate that selenium is the major element of concern. Elevated concentrations of selenium in water were restricted to tile-drain effluent. The maximum selenium concentration of 300 microg/L was detected in a tile-drain sample, and the minimum concentration of 1 microg/L was detected in a composite sample of Salton Sea water. The median selenium concentration was 19 microg/L. In contrast to the water, the highest bottom-sediment selenium concentration of 3.3 mg/kg was in a composite sample from the Salton Sea. The selenium detected in samples of waterfowl and fish also are of concern, but, to date, no studies have been done in the Salton Sea area to determine if selenium has caused adverse biological effects. Concentrations of boron and manganese were elevated in tile-drain samples throughout the Imperial Valley. Boron concentrations in migratory waterfowl were at levels that could cause reproduction impairment. Elevated concentrations of chromium, nickel, and zinc were detected in the Whitewater River , but they were not associated with irrigation drainage. Organochlorine pesticide residues were detected in bottom sediment throughout the study area at levels approaching those measured more than 10 years ago. More detailed studies would be needed to determine if these residues are affecting the waterfowl. (USGS)

Occurrence of pharmaceuticals, hormones, and organic wastewater compounds in Pennsylvania waters, 2006-09

USGS Publications Warehouse

Reif, Andrew G.; Crawford, J. Kent; Loper, Connie A.; Proctor, Arianne; Manning, Rhonda; Titler, Robert

2012-01-01

Concern over the presence of contaminants of emerging concern, such as pharmaceutical compounds, hormones, and organic wastewater compounds (OWCs), in waters of the United States and elsewhere is growing. Laboratory techniques developed within the last decade or new techniques currently under development within the U.S. Geological Survey now allow these compounds to be measured at concentrations in nanograms per liter. These new laboratory techniques were used in a reconnaissance study conducted by the U.S. Geological Survey, in cooperation with the Pennsylvania Department of Environmental Protection, to determine the occurrence of contaminants of emerging concern in streams, streambed sediment, and groundwater of Pennsylvania. Compounds analyzed for in the study are pharmaceuticals (human and veterinary drugs), hormones (natural and synthetic), and OWCs (detergents, fragrances, pesticides, industrial compounds, disinfectants, polycyclic aromatic hydrocarbons, fire retardants and plasticizers). Reconnaissance sampling was conducted from 2006 to 2009 to identify contaminants of emerging concern in (1) groundwater from wells used to supply livestock, (2) streamwater upstream and downstream from animal feeding operations, (3) streamwater upstream from and streamwater and streambed sediment downstream from municipal wastewater effluent discharges, (4) streamwater from sites within 5 miles of drinking-water intakes, and (5) streamwater and streambed sediment where fish health assessments were conducted. Of the 44 pharmaceutical compounds analyzed in groundwater samples collected in 2006 from six wells used to supply livestock, only cotinine (a nicotine metabolite) and the antibiotics tylosin and sulfamethoxazole were detected. The maximum concentration of any contaminant of emerging concern was 24 nanograms per liter (ng/L) for cotinine, and was detected in a groundwater sample from a Lebanon County, Pa., well. Seven pharmaceutical compounds including acetaminophen, caffeine, carbamazepine, and the four antibiotics tylosin, sulfadimethoxine, sulfamethoxazole, and oxytetracycline were detected in streamwater samples collected in 2006 from six paired stream sampling sites located upstream and downstream from animal-feeding operations. The highest reported concentration of these seven compounds was for the antibiotic sulfamethoxazole (157 ng/L), in a sample from the downstream site on Snitz Creek in Lancaster County, Pa. Twenty-one pharmaceutical compounds were detected in streamwater samples collected in 2006 from five paired stream sampling sites located upstream or downstream from a municipal wastewater-effluent-discharge site. The most commonly detected compounds and maximum concentrations were the anticonvulsant carbamazepine, 276 ng/L; the antihistamine diphenhydramine, 135 ng/L; and the antibiotics ofloxacin, 329 ng/L; sulfamethoxazole, 1,340 ng/L; and trimethoprim, 256 ng/L. A total of 51 different contaminants of emerging concern were detected in streamwater samples collected from 2007 through 2009 at 13 stream sampling sites located downstream from a wastewater-effluent-discharge site. The concentrations and numbers of compounds detected were higher in stream sites downstream from a wastewater-effluent-discharge site than in stream sites upstream from a wastewater-effluent-discharge site. This finding indicates that wastewater-effluent discharges are a source of contaminants of emerging concern; these contaminants were present more frequently in the streambed-sediment samples than in streamwater samples. Antibiotic compounds were often present in both the streamwater and streambed-sediment samples, but many OWCs were present exclusively in the streambed-sediment samples. Compounds with endocrine disrupting potential including detergent metabolites, pesticides, and flame retardants, were present in the streamwater and streambed-sediment samples. Killinger Creek, a stream where wastewater-effluent discharges contribute a large percentage of the total flow, stands out as a stream with particularly high numbers of compounds detected and detected at the highest concentrations measured in the reconnaissance sampling. Nineteen contaminants of emerging concern were detected in streamwater samples collected quarterly from 2007 through 2009 at 27 stream sites within 5 miles of a drinking-water intake. The number of contaminants and the concentrations detected at the stream sites within 5 miles of drinking-water intakes were generally very low (concentrations less than 50 ng/L), much lower than those at sites downstream from a wastewater-effluent discharge. The most commonly detected compounds and maximum concentrations were caffeine, 517 ng/L; carbamazepine, 95 ng/L; sulfamethoxazole, 146 ng/L; and estrone, 3.15 ng/L. The concentrations and frequencies of detection of some of the contaminants of emerging concern appear to vary by season, which could be explained by compound use, flow regime, or differences in degradation rates. Concentrations of some contaminants were associated with lower flows as a result of decreased in-stream dilution of wastewater effluents or other contamination sources. Twenty-two contaminants of emerging concern were detected once each in streamwater samples collected in 2007 and 2008 from 16 fish-health stream sites located statewide. The highest concentrations were for the OWCs, including flame retardants tri(2-butoxyethyl)phosphate (604 ng/L) and tri(2-chloroethyl)phosphate (272 ng/L) and the fragrance isoquinoline (330 ng/L). Far fewer numbers of contaminants of emerging concern were detected at the fish-health sites than at the wastewater-effluent-discharge sites. Most of the fish-health sites were not located directly downstream from a wastewater-effluent discharge, but there were multiple wastewater-effluent discharges in the drainage basins upstream from the sampling sites. No distinct pattern of contaminant occurrence could be discerned for the fish-health stream sites

Groundwater quality in the Mohawk River Basin, New York, 2011

USGS Publications Warehouse

Nystrom, Elizabeth A.; Scott, Tia-Marie

2013-01-01

Water samples were collected from 21 production and domestic wells in the Mohawk River Basin in New York in July 2011 to characterize groundwater quality in the basin. The samples were collected and processed using standard U.S. Geological Survey procedures and were analyzed for 148 physiochemical properties and constituents, including dissolved gases, major ions, nutrients, trace elements, pesticides, volatile organic compounds (VOCs), radionuclides, and indicator bacteria. The Mohawk River Basin covers 3,500 square miles in New York and is underlain by shale, sandstone, carbonate, and crystalline bedrock. The bedrock is overlain by till in much of the basin, but surficial deposits of saturated sand and gravel are present in some areas. Nine of the wells sampled in the Mohawk River Basin are completed in sand and gravel deposits, and 12 are completed in bedrock. Groundwater in the Mohawk River Basin was typically neutral or slightly basic; the water typically was very hard. Bicarbonate, chloride, calcium, and sodium were the major ions with the greatest median concentrations; the dominant nutrient was nitrate. Methane was detected in 15 samples. Strontium, iron, barium, boron, and manganese were the trace elements with the highest median concentrations. Four pesticides, all herbicides or their degradates, were detected in four samples at trace levels; three VOCs, including chloroform and two solvents, were detected in four samples. The greatest radon-222 activity, 2,300 picocuries per liter, was measured in a sample from a bedrock well, but the median radon activity was higher in samples from sand and gravel wells than in samples from bedrock wells. Coliform bacteria were detected in five samples with a maximum of 92 colony-forming units per 100 milliliters. Water quality in the Mohawk River Basin is generally good, but concentrations of some constituents equaled or exceeded current or proposed Federal or New York State drinking-water standards. The standards exceeded are color (1 sample), pH (1 sample), sodium (9 samples), chloride (1 sample), sulfate (2 samples), dissolved solids (7 samples), aluminum (3 samples), iron (8 samples), manganese (6 samples), radon-222 (10 samples), and bacteria (5 samples). Fecal coliform bacteria and Escherichia coli (E. coli) were each detected in one sample. Concentrations of fluoride, nitrate, nitrite, antimony, arsenic, barium, beryllium, cadmium, chromium, copper, lead, mercury, selenium, silver, thallium, zinc, and uranium, and gross alpha activities, did not exceed existing drinking-water standards in any of the samples collected. Methane concentrations in two samples were greater than 28 milligrams per liter, and the maximum measured concentration was 44.3 milligrams per liter.

Pesticides analysed in rainwater in Alsace region (Eastern France): Comparison between urban and rural sites

NASA Astrophysics Data System (ADS)

Scheyer, Anne; Morville, Stéphane; Mirabel, Philippe; Millet, Maurice

Current-used pesticides commonly applied in Alsace region (Eastern France) on diverse crops (maize, vineyard, vegetables, etc.) were analysed, together with Lindane, in rainwater between January 2002 and June 2003 simultaneously on two sites situated in a typical rural (Erstein, France) and urban area (Strasbourg, France). Rainwater samples were collected on a weekly basis by using two automatic wet only collectors associated with an open collector for the measurement of rainwater height. Pesticides were analysed by GC-MSMS and extracted from rainwater by SPME. Two runs were performed. The first one was performed by using a PDMS (100 μm) fibre for pesticides where direct injection into GC is possible (alachlor, atrazine, azinphos-ethyl, azinphos-methyl, captan, chlorfenvinphos, dichlorvos, diflufenican, α- and β-endosulfan, iprodione, lindane, metolachlor, mevinphos, parathion-methyl, phosalone, phosmet, tebuconazole, triadimefon and trifluralin). The second run was performed by using PDMS/DVB fibre and this run concerns pesticides where a preliminary derivatisation step with pentafluorobenzylbromide (PFBBr) is required for very low volatiles (bromoxynil,2,4-MCPA, MCPP and 2,4-D) or thermo labiles (chlorotoluron, diuron and isoproturon) pesticides. Results showed that the more concentrated pesticides detected were those used as herbicides in large quantities in Alsace region for maize crops (alachlor, metolachlor and atrazine). Maximum concentrations for these herbicides have been measured during intensive applications periods on maize crops following by rapid decrease immediately after use. For Alachlor, most important peaks have been observed between 21 and 28 April 2003 (3327 ng L -1 at Erstein and 5590 ng L -1 at Strasbourg). This is also the case for Metolachlor where most important peak was observed during the same week. Concentrations of pesticides measured out of application periods were very low for many pesticides and some others where never detected during this period. This is the case for diflufenican which was detected only during application. Two important peaks of concentrations were observed; a first one (101 ng L -1) in Erstein in November 2002 (4-11 November) and a second one (762 ng L -1) also in Erstein (28 April-15 May). The same behaviour can be seen for chlorfenvinphos and phosalone which have been detected, respectively, 2 and 4 times in Erstein and Strasbourg at high concentrations (28 April 2003-15 May 2003, 187 ng L -1 of phosalone and 157 ng L -1 of chlorfenvinphos in Erstein). MCPP, 2,4 MCPA and 2,4-D have been detected at high concentrations in rainwater but for the other pesticides very episodically and mainly during their use in agriculture. Maximal concentrations of MCPP and 2,4 MCPA have been measured in Erstein between 28 April and 15 May (904 and 746 ng L -1, respectively). Comparison between rural and urban sites showed that concentrations in rural areas are generally higher except for pesticides commonly applied in urban areas like Diuron. No seasonal phenomenon was observed for Diuron. This herbicide has been detected in practically all of the rainwater samples in Strasbourg (40/41) with a maximum of 1025 ng L -1 (16-23 September 2002) in 38 samples on 41 in Erstein with a maximum of 317 ng L -1 (15-23 October 2002). The total concentration of Diuron measured between 4 March 2002 and 20 July 2003 is of 4721 ng L -1 in Strasbourg and 5025 ng L -1 in Erstein. This result shows that wet deposition of Diuron in urban and rural sites was equivalent and can be explained by the "urban use" of this molecule together with its potential persistence.

Exposure and food web transfer of pharmaceuticals in ospreys (Pandion haliaetus): Predictive model and empirical data

USGS Publications Warehouse

Lazarus, Rebecca S.; Rattner, Barnett A.; Du, Bowen; McGowan, Peter C.; Blazer, Vicki S.; Ottinger, Mary Ann

2015-01-01

The osprey (Pandion haliaetus) is a well-known sentinel of environmental contamination, yet no studies have traced pharmaceuticals through the water–fish–osprey food web. A screening-level exposure assessment was used to evaluate the bioaccumulation potential of 113 pharmaceuticals and metabolites, and an artificial sweetener in this food web. Hypothetical concentrations in water reflecting “wastewater effluent dominated” or “dilution dominated” scenarios were combined with pH-specific bioconcentration factors (BCFs) to predict uptake in fish. Residues in fish and osprey food intake rate were used to calculate the daily intake (DI) of compounds by an adult female osprey. Fourteen pharmaceuticals and a drug metabolite with a BCF greater than 100 and a DI greater than 20 µg/kg were identified as being most likely to exceed the adult human therapeutic dose (HTD). These 15 compounds were also evaluated in a 40 day cumulative dose exposure scenario using first-order kinetics to account for uptake and elimination. Assuming comparable absorption to humans, the half-lives (t1/2) for an adult osprey to reach the HTD within 40 days were calculated. For 3 of these pharmaceuticals, the estimated t1/2 in ospreys was less than that for humans, and thus an osprey might theoretically reach or exceed the HTD in 3 to 7 days. To complement the exposure model, 24 compounds were quantified in water, fish plasma, and osprey nestling plasma from 7 potentially impaired locations in Chesapeake Bay. Of the 18 analytes detected in water, 8 were found in fish plasma, but only 1 in osprey plasma (the antihypertensive diltiazem). Compared to diltiazem detection rate and concentrations in water (10/12 detects,

[Investigation of concentration levels of chromium(VI) in bottled mineral and spring waters by high performance ion chromatography technique with application of postcolumn reaction with 1,5-diphenylcarbazide and VIS detection].

PubMed

Swiecicka, Dorota; Garboś, Sławomir

2008-01-01

The aim of this work was optimization and validation of the method of determination of Cr(VI) existing in the form of chromate(VI) in mineral and spring waters by High Performance Ion Chromatography (HPIC) technique with application of postcolumn reaction with 1,5-diphenylcarbazide and VIS detection. Optimization of the method performed with the use of initial apparatus parameters and chromatographic conditions from the Method 218.6 allowed to lowering detection limit for Cr(VI) from 400 ng/l to 2 ng/l. Thanks to very low detection limit achieved it was possible to determine of Cr(VI) concentrations in 25 mineral and spring waters presented at Polish market. In the cases of four mineral and spring waters analyzed, determined Cr(VI) concentrations were below of quantification limit (< 4 ng/l) but simultaneously in another mineral and spring waters the concentrations of chromium(VI) were determined in the range of 5.6 - 1281 ng/l. The fact of existence of different Cr(VI) concentrations in investigated waters could be connected with secondary contamination of mineral and spring waters by chromium coming from metal installations and fittings. One should be underlined that even the highest determined concentration level of chromium(VI) was below of the maximum admissible concentration of total chromium presented in Polish Decree of Minister of Health from April 29th 2004. Therefore after taking into account determined in this work concentration of Cr(VI), the consumption of all waters analyzed in this study does not lead to essential human health risk.

Quantitative Assessment of Detection Frequency for the INL Ambient Air Monitoring Network

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sondrup, A. Jeffrey; Rood, Arthur S.

A quantitative assessment of the Idaho National Laboratory (INL) air monitoring network was performed using frequency of detection as the performance metric. The INL air monitoring network consists of 37 low-volume air samplers in 31 different locations. Twenty of the samplers are located on INL (onsite) and 17 are located off INL (offsite). Detection frequencies were calculated using both BEA and ESER laboratory minimum detectable activity (MDA) levels. The CALPUFF Lagrangian puff dispersion model, coupled with 1 year of meteorological data, was used to calculate time-integrated concentrations at sampler locations for a 1-hour release of unit activity (1 Ci) formore » every hour of the year. The unit-activity time-integrated concentration (TICu) values were calculated at all samplers for releases from eight INL facilities. The TICu values were then scaled and integrated for a given release quantity and release duration. All facilities modeled a ground-level release emanating either from the center of the facility or at a point where significant emissions are possible. In addition to ground-level releases, three existing stacks at the Advanced Test Reactor Complex, Idaho Nuclear Technology and Engineering Center, and Material and Fuels Complex were also modeled. Meteorological data from the 35 stations comprising the INL Mesonet network, data from the Idaho Falls Regional airport, upper air data from the Boise airport, and three-dimensional gridded data from the weather research forecasting model were used for modeling. Three representative radionuclides identified as key radionuclides in INL’s annual National Emission Standards for Hazardous Air Pollutants evaluations were considered for the frequency of detection analysis: Cs-137 (beta-gamma emitter), Pu-239 (alpha emitter), and Sr-90 (beta emitter). Source-specific release quantities were calculated for each radionuclide, such that the maximum inhalation dose at any publicly accessible sampler or the National Emission Standards for Hazardous Air Pollutants maximum exposed individual location (i.e., Frenchman’s Cabin) was no more than 0.1 mrem yr–1 (i.e., 1% of the 10 mrem yr–1 standard). Detection frequencies were calculated separately for the onsite and offsite monitoring network. As expected, detection frequencies were generally less for the offsite sampling network compared to the onsite network. Overall, the monitoring network is very effective at detecting the potential releases of Cs-137 or Sr-90 from all sources/facilities using either the ESER or BEA MDAs. The network was less effective at detecting releases of Pu-239. Maximum detection frequencies for Pu-239 using ESER MDAs ranged from 27.4 to 100% for onsite samplers and 3 to 80% for offsite samplers. Using BEA MDAs, the maximum detection frequencies for Pu-239 ranged from 2.1 to 100% for onsite samplers and 0 to 5.9% for offsite samplers. The only release that was not detected by any of the samplers under any conditions was a release of Pu-239 from the Idaho Nuclear Technology and Engineering Center main stack (CPP-708). The methodology described in this report could be used to improve sampler placement and detection frequency, provided clear performance objectives are defined.« less

Research of the fluorescence detection apparatus for nutrients

NASA Astrophysics Data System (ADS)

Wang, Yu; Yan, Huimin; Ni, Xuxiang; Xu, Xiaoyi; Chen, Shibing

2015-10-01

The research of the multifunctional analyzer of Clinical Nutrition, which integrates the absorbance, luminescence, fluorescence and other optical detection methods, can overcome the functional limitations of a single technology on human nutrition analysis, and realize a rapid and accurate analysis of the nutrients. This article focuses on the design of fluorescence detection module that uses a photomultiplier tube(PMT) to detect weak fluorescence, and utilizes the single photon counting method to measure the fluorescence intensity, and then according to the relationship between the fluorescent marker and fluorescence intensity, the concentration of the analyte can be derived. Using fluorescein isothiocyanate(FITC, the most widely used fluorescein currently)to mark antibodies in the experiment, therefore, according to the maximum absorption wavelength and the maximum emission wavelength of the fluorescein isothiocyanate, to select the appropriate filters to set up the optical path. In addition, the fluorescence detection apparatus proposed in this paper uses an aspherical lens with large numerical aperture, in order to improve the capacity of signal acquisition more effectively, and the selective adoption of flexible optical fiber can realize a compact opto-mechanical structure, which is also conducive to the miniaturization of the device. The experimental results show that this apparatus has a high sensitivity, can be used for the detection and analysis of human nutrition.

Potency of sensor displacement detection of cholesterol concentration using flat mirror as media for learning waves and optics

NASA Astrophysics Data System (ADS)

Budiyanto, M.; Suhariningsih; Yasin, M.

2018-04-01

The use of instructional media needs to be implemented in one of the courses such as wave and optics to cover up the contents of material. To bring this advantage, one of the alternatives that can be used is to use fiber optic sensors for detecting cholesterol concentration. This device brings about the concepts of how the wave and optics behaves and operates. In doing so, the variation concentration of cholesterol solution is 0 ppm, 50 ppm, 100 ppm, 150 ppm, 200 ppm, 250 ppm, and 300 ppm. The work mechanism of cholesterol concentration detection is laser propagation of He-Ne wavelength 632.5 nm through fiber optic in cholesterol solution and reflected back by flat mirror then ray reflected through fiber optic bundle so detected by SL-818 silicon detector in the form of voltage Output. The detection results showed that the maximum output voltage showed a linear decrease in the concentration of cholesterol solution with a sensitivity of 0.21 mV/ppm and linearity of more than 95%. In terms of developed learning media, the use of optical fiber sensor learning media is compatible with optical wave learning in terms of basic competence of lectures, learning indicators, learning materials, student worksheets and science process skills. From the assessment of validation of learning media obtained an assessment of more than 95%. The results of this study indicate the parameters and performance of sensors that have accurate potential as a medium for learning wave and optics.

Determination of phenolic compounds and hydroxymethylfurfural in meads using high performance liquid chromatography with coulometric-array and UV detection.

PubMed

Kahoun, David; Rezková, Sona; Veskrnová, Katerina; Královský, Josef; Holcapek, Michal

2008-08-15

The objective of this study was the determination of 25 phenolic compounds in different mead samples (honeywines) using high performance liquid chromatography (HPLC) with coulometric-array detection and in case of hydroxymethylfurfural with UV detection. Our method was optimized in respect to both the separation selectivity of individual phenolic compounds and the maximum sensitivity with the electrochemical detection. The method development included the optimization of mobile phase composition, the pH value, conditions of the gradient elution and the flow rate using a window-diagram approach. The developed method was used for the determination of limits of detection and limits of quantitation for individual compounds. The linearity of calibration curves, accuracy and precision (intra- and inter-day) at three concentration levels (low, middle and high concentration range) were verified. Mead samples were diluted with the mobile phase at 1:1 to 1:50 ratio depending on the concentration and filtered through a PTFE filter without any other sample pre-treatment. Phenolic compounds concentration was determined in 50 real samples of meads and correlated with meads composition and hydroxymethylfurfural concentration. The most frequently occurred compounds were protocatechuic acid and vanillic acid (both of them were present in 98% samples), the least occurred compounds were (+)-catechin (10% samples) and sinapic acid (12% samples). Vanillin and ethylvanillin, which are used as artificial additives for the taste improvement, were found in 60% and 42% samples, respectively. Hydroxymethylfurfural concentration, as an indicator of honey quality, was in the range from 2.47 to 158 mg/L. Our method is applicable for the determination of 25 phenolic compounds in mead, honey and related natural samples.

The Effect of Heat Stress on Tomato Pollen Characteristics is Associated with Changes in Carbohydrate Concentration in the Developing Anthers

PubMed Central

PRESSMAN, ETAN; PEET, MARY M.; PHARR, D. MASON

2002-01-01

Continuous exposure of tomato ‘Trust’ to high temperatures (day/night temperatures of 32/26 °C) markedly reduced the number of pollen grains per flower and decreased viability. The effect of heat stress on pollen viability was associated with alterations in carbohydrate metabolism in various parts of the anther during its development. Under control, favourable temperature conditions (28/22 °C), starch accumulated in the pollen grains, where it reached a maximum value 3 d before anthesis; it then diminished towards anthesis. During anther development, the concentration of total soluble sugars gradually increased in the anther walls and in the pollen grains (but not in the locular fluid), reaching a maximum at anthesis. Continuous exposure of the plants to high temperatures (32/26 °C) prevented the transient increase in starch concentration and led to decreases in the concentrations of soluble sugars in the anther walls and the pollen grains. In the locular fluid, however, a higher soluble sugar concentration was detected under the high‐temperature regime throughout anther development. These results suggest that a major effect of heat stress on pollen development is a decrease in starch concentration 3 d before anthesis, which results in a decreased sugar concentration in the mature pollen grains. These events possibly contribute to the decreased pollen viability in tomato. PMID:12466104

Precise tremor source locations and amplitude variations along the lower-crustal central San Andreas Fault

USGS Publications Warehouse

Shelly, David R.; Hardebeck, Jeanne L.

2010-01-01

We precisely locate 88 tremor families along the central San Andreas Fault using a 3D velocity model and numerous P and S wave arrival times estimated from seismogram stacks of up to 400 events per tremor family. Maximum tremor amplitudes vary along the fault by at least a factor of 7, with by far the strongest sources along a 25 km section of the fault southeast of Parkfield. We also identify many weaker tremor families, which have largely escaped prior detection. Together, these sources extend 150 km along the fault, beneath creeping, transitional, and locked sections of the upper crustal fault. Depths are mostly between 18 and 28 km, in the lower crust. Epicenters are concentrated within 3 km of the surface trace, implying a nearly vertical fault. A prominent gap in detectible activity is located directly beneath the region of maximum slip in the 2004 magnitude 6.0 Parkfield earthquake.

VOCs in shallow groundwater in new residential/commercial areas of the United States

USGS Publications Warehouse

Squillace, P.J.; Moran, M.J.; Price, C.V.

2004-01-01

The quality of shallow groundwater in urban areas was investigated by sampling 518 monitoring wells between 1996 and 2002 as part of the National Water-Quality Assessment Program of the U.S. Geological Survey. Well networks were installed primarily in new residential/commercial areas less than about 30 years old (17 studies) and in small towns (2 studies) by randomly locating as many as 30 monitoring wells in each study area. The median well depth was 10 m. Based on samples with age-date information, almost all groundwater was recharged after 1950. Samples were analyzed for 53 volatile organic compounds (VOCs). Concentrations ranged from about 0.001 to 1000 ??g/L (median 0.04), with less than 1% of the samples exceeding a Maximum Contamination Level or Drinking Water Advisory established by the U.S. Environmental Protection Agency. Using uncensored concentration data, at least one VOC was detected in 88% of the samples, and at least two VOCs were detected in 69% of the samples. Chloroform, toluene, and perchloroethene were the three most frequently detected VOCs. Dissolved oxygen concentration, estimated recharge index, and land-use were significant variables in logistic regression models that explained the presence of the commonly detected VOCs. Dissolved oxygen concentration was the most important explanatory variable in logistic regression models for 6 of the 14 most frequently detected VOCs. Bromodichloromethane, chloroform, and 1,1,1-trichloroethane had a positive correlation with dissolved oxygen; in contrast, dichloroethane, benzene, and toluene had a negative correlation with dissolved oxygen.

Watershed Regressions for Pesticides (WARP) for Predicting Annual Maximum and Annual Maximum Moving-Average Concentrations of Atrazine in Streams

USGS Publications Warehouse

Stone, Wesley W.; Gilliom, Robert J.; Crawford, Charles G.

2008-01-01

Regression models were developed for predicting annual maximum and selected annual maximum moving-average concentrations of atrazine in streams using the Watershed Regressions for Pesticides (WARP) methodology developed by the National Water-Quality Assessment Program (NAWQA) of the U.S. Geological Survey (USGS). The current effort builds on the original WARP models, which were based on the annual mean and selected percentiles of the annual frequency distribution of atrazine concentrations. Estimates of annual maximum and annual maximum moving-average concentrations for selected durations are needed to characterize the levels of atrazine and other pesticides for comparison to specific water-quality benchmarks for evaluation of potential concerns regarding human health or aquatic life. Separate regression models were derived for the annual maximum and annual maximum 21-day, 60-day, and 90-day moving-average concentrations. Development of the regression models used the same explanatory variables, transformations, model development data, model validation data, and regression methods as those used in the original development of WARP. The models accounted for 72 to 75 percent of the variability in the concentration statistics among the 112 sampling sites used for model development. Predicted concentration statistics from the four models were within a factor of 10 of the observed concentration statistics for most of the model development and validation sites. Overall, performance of the models for the development and validation sites supports the application of the WARP models for predicting annual maximum and selected annual maximum moving-average atrazine concentration in streams and provides a framework to interpret the predictions in terms of uncertainty. For streams with inadequate direct measurements of atrazine concentrations, the WARP model predictions for the annual maximum and the annual maximum moving-average atrazine concentrations can be used to characterize the probable levels of atrazine for comparison to specific water-quality benchmarks. Sites with a high probability of exceeding a benchmark for human health or aquatic life can be prioritized for monitoring.

Migration of cyclo-diBA from coatings into canned food: method of analysis, concentration determined in a survey and in silico hazard profiling.

PubMed

Biedermann, Sandra; Zurfluh, Michael; Grob, Koni; Vedani, Angelo; Brüschweiler, Beat J

2013-08-01

Cyclo-diBA, the cyclic product formed from bisphenol A and bisphenol A diglycidyl ether during production of epoxy resins, was measured in canned food using reversed phase HPLC with fluorescence detection. Half (9 of 17) of the samples of canned fish in oil collected in April 2010 contained cyclo-diBA with an average concentration of 1025 μg/kg and a maximum of 1980 μg/kg. In September 2012, cyclo-diBA was detectable (>25 μg/kg) in merely 13 from 44 such products; the average concentration in these was 807 μg/kg and the maximum now reached 2640 μg/kg. Fish in brine contained far less cyclo-diBA. The majority of the canned meat products contained cyclo-diBA at a mean concentration of 477 μg/kg and a maximum of 1050 μg/kg. All prepared meals, such as ravioli or soups, contained cyclo-diBA, with a mean at 287 μg/kg. In canned tomatoes, peas and other vegetables in water or fruits in syrup, no cyclo-diBA was detected (<25 μg/kg). Since no experimental toxicity data are available except for its cytotoxicity, an in silico hazard profiling was performed. Cyclo-diBA seems to be stable and of low reactivity. There is indication for considerable oral bioavailability and for the potential to accumulate in the human body. Cyclo-diBA can be metabolized into cyclic and acyclic compounds. Based on SAR assessment for cyclo-diBA and read-across from BADGE to linear cyclo-diBA metabolites, genotoxic effects are improbable. Specific binding of cyclo-diBA to nuclear receptors, such as ERβ, can be predicted, indicating a potential endocrine-disrupting potency. The limit by the EFSA guidelines of 50 μg/person/d for compounds shown not to be genotoxic as well as the TTC-based Cramer structural class III value of 90 μg/person/d could be exceeded several fold by high consumers of canned fish in oil with high brand loyalty. As a consequence, risk reduction measures were taken. Copyright © 2013 Elsevier Ltd. All rights reserved.

Occurrence of selected radionuclides in ground water used for drinking water in the United States; a reconnaissance survey, 1998

USGS Publications Warehouse

Focazio, Michael J.; Szabo, Zoltan; Kraemer, Thomas F.; Mullin, Ann H.; Barringer, Thomas H.; dePaul, Vincent T.

2001-01-01

The U.S. Geological Survey, in collaboration with the U.S. Environmental Protection Agency, the American Water Works Association, and the American Water Works Service Company, completed a targeted national reconnaissance survey of selected radionuclides in public ground-water supplies. Radionuclides analyzed included radium-224 (Ra-224), radium-226 (Ra-226), radium-228 (Ra-228), polonium-210 (Po-210) and lead-210 (Pb-210).This U.S. Geological Survey reconnaissance survey focused intentionally on areas with known or suspected elevated concentrations of radium in ground water to determine if Ra-224 was also present in the areas where other isotopes of radium had previously been detected and to determine the co-occurrence characteristics of the three radium isotopes (Ra-224, Ra-226, and Ra-228) in those areas. Ninety-nine raw-water samples (before water treatment) were collected once over a 6-month period in 1998 and 1999 from wells (94 of which are used for public drinking water) in 27 States and 8 physiographic provinces. Twenty-one of the 99 samples exceeded the current U.S. Environmental Protection Agency drinking-water maximum contaminant level of 5 picocuries per liter (pCi/L) for combined radium (Ra-226 + Ra-228). Concentrations of Ra-224 were reported to exceed 1 pCi/L in 30 percent of the samples collected, with a maximum concentration of 73.6 pCi/L measured in water from a nontransient, noncommunity, public-supply well in Maryland. Radium-224 concentrations generally were higher than those of the other isotopes of radium. About 5 percent of the samples contained concentrations of Ra-224 greater than 10 pCi/L, whereas only 2 percent exceeded 10 pCi/L for either Ra-226 or Ra-228. Concentrations of Ra-226 greater than 1 pCi/L were reported in 33 percent of the samples, with a maximum concentration of 16.9 pCi/L measured in water from a public-supply well in Iowa. Concentrations of Ra-228 greater than 1 pCi/L were reported in 22 samples, with a maximum concentration of 72.3 pCi/L measured in water from a non-transient, noncommunity, public-supply well in Maryland.Radium-224, which is a decay product of Ra-228 in the Th-232 decay series, was significantly correlated with Ra-228 (Spearman?s rank correlation coefficient ?r? equals 0.82) and to a lesser degree with Ra-226 (r equals 0.69), which is an isotope in the U-238 decay series. The rank correlation coefficient between Ra-226 and Ra-228 was 0.63. The high correlation between Ra-224 and Ra-228 concentrations and the corresponding isotopic ratios of the two (about 1:1 in 90 percent of the samples) indicates that the two radionuclides occur in approximately equal concentrations in most ground water sampled. Thus, Ra-228 can be considered as a reasonable proxy indicator for the occurrence of Ra-224 in ground water.The maximum concentration of Po-210 was 4.85 pCi/L and exceeded 1 pCi/L in only two samples. The maximum concentration of Pb-210 was 4.14 pCi/L, and about 10 percent of the samples exceeded 1 pCi/L. Areas with known, or suspected, elevated concentrations of polonium and lead were not targeted in this survey.Three major implications are drawn for future radionuclide monitoring on the basis of this information: (1) grossalpha particle analyses of ground water should be done within about 48?72 hours after collection to determine the presence of the short-lived, alpha-particle emitting isotopes, such as Ra-224, which was detected in elevated concentrations in many of the samples collected for this survey; (2) the isotope ratios of Ra-224 to Ra-228 in ground water are variable on a national scale, but the two radioisotopes generally occur in ratios near 1:1, therefore, the more commonly measured Ra-228 can be used as an indicator of Ra-224 occurrence for some general purposes other than compliance; and (3) the isotopic ratios of Ra-226 to Ra-228 were less than 3:2 in many samples. These ratios corroborate results of previous studies that have shown the presence of Ra-228

Detection of Legionella, L. pneumophila and Mycobacterium Avium Complex (MAC) along Potable Water Distribution Pipelines

PubMed Central

Whiley, Harriet; Keegan, Alexandra; Fallowfield, Howard; Bentham, Richard

2014-01-01

Inhalation of potable water presents a potential route of exposure to opportunistic pathogens and hence warrants significant public health concern. This study used qPCR to detect opportunistic pathogens Legionella spp., L. pneumophila and MAC at multiple points along two potable water distribution pipelines. One used chlorine disinfection and the other chloramine disinfection. Samples were collected four times over the year to provide seasonal variation and the chlorine or chloramine residual was measured during collection. Legionella spp., L. pneumophila and MAC were detected in both distribution systems throughout the year and were all detected at a maximum concentration of 103 copies/mL in the chlorine disinfected system and 106, 103 and 104 copies/mL respectively in the chloramine disinfected system. The concentrations of these opportunistic pathogens were primarily controlled throughout the distribution network through the maintenance of disinfection residuals. At a dead-end and when the disinfection residual was not maintained significant (p < 0.05) increases in concentration were observed when compared to the concentration measured closest to the processing plant in the same pipeline and sampling period. Total coliforms were not present in any water sample collected. This study demonstrates the ability of Legionella spp., L. pneumophila and MAC to survive the potable water disinfection process and highlights the need for greater measures to control these organisms along the distribution pipeline and at point of use. PMID:25046636

Detection of Legionella, L. pneumophila and Mycobacterium avium complex (MAC) along potable water distribution pipelines.

PubMed

Whiley, Harriet; Keegan, Alexandra; Fallowfield, Howard; Bentham, Richard

2014-07-18

Inhalation of potable water presents a potential route of exposure to opportunistic pathogens and hence warrants significant public health concern. This study used qPCR to detect opportunistic pathogens Legionella spp., L. pneumophila and MAC at multiple points along two potable water distribution pipelines. One used chlorine disinfection and the other chloramine disinfection. Samples were collected four times over the year to provide seasonal variation and the chlorine or chloramine residual was measured during collection. Legionella spp., L. pneumophila and MAC were detected in both distribution systems throughout the year and were all detected at a maximum concentration of 103 copies/mL in the chlorine disinfected system and 106, 103 and 104 copies/mL respectively in the chloramine disinfected system. The concentrations of these opportunistic pathogens were primarily controlled throughout the distribution network through the maintenance of disinfection residuals. At a dead-end and when the disinfection residual was not maintained significant (p < 0.05) increases in concentration were observed when compared to the concentration measured closest to the processing plant in the same pipeline and sampling period. Total coliforms were not present in any water sample collected. This study demonstrates the ability of Legionella spp., L. pneumophila and MAC to survive the potable water disinfection process and highlights the need for greater measures to control these organisms along the distribution pipeline and at point of use.

Automatic Seizure Detection in Rats Using Laplacian EEG and Verification with Human Seizure Signals

PubMed Central

Feltane, Amal; Boudreaux-Bartels, G. Faye; Besio, Walter

2012-01-01

Automated detection of seizures is still a challenging problem. This study presents an approach to detect seizure segments in Laplacian electroencephalography (tEEG) recorded from rats using the tripolar concentric ring electrode (TCRE) configuration. Three features, namely, median absolute deviation, approximate entropy, and maximum singular value were calculated and used as inputs into two different classifiers: support vector machines and adaptive boosting. The relative performance of the extracted features on TCRE tEEG was examined. Results are obtained with an overall accuracy between 84.81 and 96.51%. In addition to using TCRE tEEG data, the seizure detection algorithm was also applied to the recorded EEG signals from Andrzejak et al. database to show the efficiency of the proposed method for seizure detection. PMID:23073989

Effect of tetrastarch (hydroxyethyl starch 130/0.4) on plasma creatinine concentration in cats: a retrospective analysis (2010-2015).

PubMed

Yozova, Ivayla D; Howard, Judith; Adamik, Katja N

2017-10-01

Objectives The objective was to determine survival and changes in creatinine concentrations after administration of 6% tetrastarch (hydroxyethyl starch [HES] 130/0.4) vs crystalloids in critically ill cats. Methods The medical records were reviewed for cats admitted to the intensive care unit with at least two plasma creatinine measurements and initial concentrations not exceeding the upper reference interval. Cats were excluded if they had received HES prior to admission or if they had received fluid therapy for <24 h between initial and subsequent measurements. Changes in creatinine concentrations were evaluated as the percentage change from initial values to the maximum subsequent measurements. Cats receiving only crystalloids were assigned to the crystalloid group; cats receiving only HES or HES and crystalloids were assigned to the HES group. Results Ninety-three cats were included in the study (62 in the crystalloid group, 31 in the HES group). The total median cumulative HES dose was 94 ml/kg (range 26-422 ml/kg) and 24 ml/kg/day (range 16-42 ml/kg/day). No difference was detected between the groups for age, sex, body weight or mortality. The HES group had a significantly longer length of hospitalisation ( P = 0.012), lower albumin concentrations ( P <0.001), higher Acute Patient Physiologic and Laboratory Evaluation scores ( P = 0.037) and higher incidence of systemic inflammatory response syndrome ( P = 0.009) and sepsis ( P = 0.013). There was no significant difference in initial, maximum or maximum change in creatinine concentrations between the groups. Moreover, there was no significant difference in maximum change in creatinine concentrations in the subgroups of cats with systemic inflammatory response syndrome or sepsis. Conclusions and relevance In this population of cats, the administration of HES did not result in a significantly greater increase in creatinine from values measured on admission or higher mortality compared with administration of crystalloids. Further prospective studies are needed to assess both safety and efficacy of HES in cats before recommendations can be made.

California GAMA program: ground-water quality data in the San Diego drainages hydrogeologic province, California, 2004

USGS Publications Warehouse

Wright, Michael T.; Belitz, Kenneth; Burton, Carmen A.

2005-01-01

Because of concerns over ground-water quality, the California State Water Resources Control Board (SWRCB), in collaboration with the U.S. Geological Survey and Lawrence Livermore National Laboratory, has implemented the Ground-Water Ambient Monitoring and Assessment (GAMA) Program. A primary objective of the program is to provide a current assessment of ground-water quality in areas where public supply wells are an important source of drinking water. The San Diego GAMA study unit was the first region of the state where an assessment of ground-water quality was implemented under the GAMA program. The San Diego GAMA study unit covers the entire San Diego Drainages hydrogeologic province, and is broken down into four distinct hydrogeologic study areas: the Temecula Valley study area, the Warner Valley study area, the Alluvial Basins study area, and the Hard Rock study area. A total of 58 ground-water samples were collected from public supply wells in the San Diego GAMA study unit: 19 wells were sampled in the Temecula Valley study area, 9 in the Warner Valley study area, 17 in the Alluvial Basins study area, and 13 in the Hard Rock study area. Over 350 chemical and microbial constituents and water-quality indicators were analyzed for in this study. However, only select wells were measured for all constituents and water-quality indicators. Results of analyses were calculated as detection frequencies by constituent classification and by individual constituents for the entire San Diego GAMA study unit and for the individual study areas. Additionally, concentrations of constituents that are routinely monitored were compared to maximum contaminant levels (MCL) and secondary maximum contaminant levels (SMCL). Concentrations of constituents classified as 'unregulated chemicals for which monitoring is required' (UCMR) were compared to the 'detection level for the purposes of reporting' (DLR). Eighteen of the 88 volatile organic compounds (VOCs) and gasoline oxygenates analyzed for were detected in ground-water samples. Twenty-eight wells sampled in the San Diego GAMA study had at least a single detection of VOCs or gasoline oxygenates. These constituents were most frequently detected in the Alluvial Basin study area (11 of 17 wells), and least frequently detected in the Warner Valley study area (one of nine wells). Trihalomethanes (THMs) were the most frequently detected class of VOCs (18 of 58 wells). The most frequently detected VOCs were chloroform (18 of 58 wells), bromodichloromethane (8 of 58 wells), and methyl tert-butyl ether (MTBE) (7 of 58 wells). Three VOCs were detected at concentrations greater than their MCLs. Tetrachloroethylene (PCE) and trichloroethylene (TCE) were detected in one well in the Hard Rock study area at concentrations of 9.75 and 7.27 micrograms per liter (?g/L), respectively; the MCL for these compounds is 5 ?g/L. MTBE was detected in one well in the Alluvial Basins study area at a concentration of 28.3 ?g/L; the MCL for MTBE is 13 ?g/L. Twenty-one of the 122 pesticides and pesticide degradates analyzed for were detected in ground-water samples. Pesticide or pesticide degradates were detected in 33 of 58 wells sampled, and were most frequently detected in the Temecula Valley study area wells (9 of 14 wells), and least frequently in the Warner Valley study area wells (3 of 9 wells). Herbicides were the most frequently detected class of pesticides (31 of 58 wells), and simazine was the most frequently detected compound (27 of 58 wells), followed by deethylatrazine (14 of 58 wells), prometon (10 of 58 wells), and atrazine (9 of 58 wells). None of the pesticides detected in ground-water samples had concentrations that exceeded MCLs. Eight waste-water indicator compounds were detected in ground-water samples. Twenty-one of 47 wells sampled for waste-water indicator compounds had at least a single detection. Waste-water indicator compounds were detected most frequently in the Allu

An electrochemical magneto immunosensor (EMIS) for the determination of paraquat residues in potato samples.

PubMed

Garcia-Febrero, Raul; Valera, Enrique; Muriano, Alejandro; Pividori, M-Isabel; Sanchez-Baeza, Francisco; Marco, M-Pilar

2013-09-01

An electrochemical magneto immunosensor for the detection of low concentrations of paraquat (PQ) in food samples has been developed and its performance evaluated in a complex sample such as potato extracts. The immunosensor presented uses immunoreagents specifically developed for the recognition of paraquat, a magnetic graphite-epoxy composite (m-GEC) electrode and biofunctionalized magnetic micro-particles (PQ1-BSAMP) that allow reduction of the potential interferences caused by the matrix components. The amperometric signal is provided by an enzymatic probe prepared by covalently linking an enzyme to the specific antibodies (Ab198-cc-HRP). The use of hydroquinone, as mediator, allows recording of the signal at a low potential, which also contributes to reducing the background noise potentially caused by the sample matrix. The immunocomplexes formed on top of the modified MP are easily captured by the m-GEC, which acts simultaneously as transducer. PQ can be detected at concentrations as low as 0.18 ± 0.09 μg L(-1). Combined with an efficient extraction procedure, PQ residues can be directly detected and accurately quantified in potato extracts without additional clean-up or purification steps, with a limit of detection (90% of the maximum signal) of 2.18 ± 2.08 μg kg(-1), far below the maximum residue level (20 μg kg(-1)) established by the EC. The immunosensor presented here is suitable for on-site analysis. Combined with the use of magnetic racks, multiple samples can be run simultaneously in a reasonable time.

Residues of veterinary antibiotics in manures from feedlot livestock in eight provinces of China.

PubMed

Zhao, Ling; Dong, Yuan Hua; Wang, Hui

2010-02-01

The residue levels of selected fluoroquinolones, sulfonamides and tetracyclines in 143 animal dung samples collected in 2007 from large-scale livestock and poultry feedlots in 8 provinces were determined by using ultrasonic extraction and liquid chromatography. Recoveries from spiked pig dung samples (spike level=1mg/kg) ranged from 73.9 to 102.0% for fluoroquinolones, from 81.6 to 92.3% for sulfonamides, and from 57.2 to 72.6% for tetracyclines. Relative standard deviations of the recoveries were less than 10% within the same day. Method quantification limits were measured from 0.031 to 0.150 mg/kg for fluoroquinolones, from 0.023 to 0.082 mg/kg for sulfonamides, and 0.091 to 0.182 mg/kg for tetracyclines in spiked pig manure samples. Analysis of 61 pig, 54 chicken and 28 cow dung samples collected in China revealed that in pig and cow dung, up to 33.98 and 29.59 mg/kg ciprofloxacin, 33.26 and 46.70 mg/kg enrofloxacin, 59.06 and 59.59 mg/kg oxytetracycline, and 21.06 and 27.59 mg/kg chlortetracycline could be detected, respectively. A maximum concentration of 99.43 mg/kg fleroxacin, 225.45 mg/kg norfloxacin, 45.59 mg/kg ciprofloxacin and 1420.76 mg/kg enrofloxacin could be detected in chicken dung. No appreciable sulfonamide antibiotic concentrations (less than 10mg/kg) were found in any animal dung, and only sulfadimidine was observed, at a maximum concentration of 6.04 mg/kg, in chicken dung. Both enrofloxacin and chlortetracycline were detected with a very high occurrence in three animal manure samples. The residue levels for most antibiotics showed significant statistical differences among the sampling districts and the animal species. Copyright 2009 Elsevier B.V. All rights reserved.

Magnetotelluric Detection Thresholds as a Function of Leakage Plume Depth, TDS and Volume

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, X.; Buscheck, T. A.; Mansoor, K.

We conducted a synthetic magnetotelluric (MT) data analysis to establish a set of specific thresholds of plume depth, TDS concentration and volume for detection of brine and CO 2 leakage from legacy wells into shallow aquifers in support of Strategic Monitoring Subtask 4.1 of the US DOE National Risk Assessment Partnership (NRAP Phase II), which is to develop geophysical forward modeling tools. 900 synthetic MT data sets span 9 plume depths, 10 TDS concentrations and 10 plume volumes. The monitoring protocol consisted of 10 MT stations in a 2×5 grid laid out along the flow direction. We model the MTmore » response in the audio frequency range of 1 Hz to 10 kHz with a 50 Ωm baseline resistivity and the maximum depth up to 2000 m. Scatter plots show the MT detection thresholds for a trio of plume depth, TDS concentration and volume. Plumes with a large volume and high TDS located at a shallow depth produce a strong MT signal. We demonstrate that the MT method with surface based sensors can detect a brine and CO 2 plume so long as the plume depth, TDS concentration and volume are above the thresholds. However, it is unlikely to detect a plume at a depth larger than 1000 m with the change of TDS concentration smaller than 10%. Simulated aquifer impact data based on the Kimberlina site provides a more realistic view of the leakage plume distribution than rectangular synthetic plumes in this sensitivity study, and it will be used to estimate MT responses over simulated brine and CO 2 plumes and to evaluate the leakage detectability. Integration of the simulated aquifer impact data and the MT method into the NRAP DREAM tool may provide an optimized MT survey configuration for MT data collection. This study presents a viable approach for sensitivity study of geophysical monitoring methods for leakage detection. The results come in handy for rapid assessment of leakage detectability.« less

Portable Chemical Agent Detection System: Differential Reflectometer and Light Scattering Approaches

DTIC Science & Technology

2005-02-15

possible to conduct elemental analysis on modified capillaries because of the polymer coating. Instead, measurements of electroosmotic flow were used...design There are several essential requirements for a sensitive chemiluminescence cell (Figure 1); good reagent/analyte mixing for maximum photon yield...Cutaway of Chemiluminescence cell the cooled pint housing. In our design, the concentric inlets will increase photon collection due to better mixing of

Carbon Dioxide Concentrations and Temperatures within Tour Buses under Real-Time Traffic Conditions.

PubMed

Chiu, Chun-Fu; Chen, Ming-Hung; Chang, Feng-Hsiang

2015-01-01

This study monitored the carbon dioxide (CO2) concentrations and temperatures of three 43-seat tour buses with high-passenger capacities in a course of a three-day, two-night school excursion. Results showed that both driver zones and passenger zones of the tour buses achieved maximum CO2 concentrations of more than 3000 ppm, and maximum daily average concentrations of 2510.6 and 2646.9 ppm, respectively. The findings confirmed that the CO2 concentrations detected in the tour buses exceeded the indoor air quality standard of Taiwan Environmental Protection Administration (8 hr-CO2: 1000 ppm) and the air quality guideline of Hong Kong Environmental Protection Department (1 hr-CO2: 2500 ppm for Level 1 for buses). Observations also showed that high-capacity tour bus cabins with air conditioning system operating in recirculation mode are severely lacking in air exchange rate, which may negatively impact transportation safety. Moreover, the passenger zones were able to maintain a temperature of between 20 and 25°C during travel, which effectively suppresses the dispersion of volatile organic compounds. Finally, the authors suggest that in the journey, increasing the ventilation frequency of tour bus cabin, which is very beneficial to maintain the travel safety and enhance the quality of travel.

Carbon Dioxide Concentrations and Temperatures within Tour Buses under Real-Time Traffic Conditions

PubMed Central

Chiu, Chun-Fu; Chen, Ming-Hung; Chang, Feng-Hsiang

2015-01-01

This study monitored the carbon dioxide (CO2) concentrations and temperatures of three 43-seat tour buses with high-passenger capacities in a course of a three-day, two-night school excursion. Results showed that both driver zones and passenger zones of the tour buses achieved maximum CO2 concentrations of more than 3000 ppm, and maximum daily average concentrations of 2510.6 and 2646.9 ppm, respectively. The findings confirmed that the CO2 concentrations detected in the tour buses exceeded the indoor air quality standard of Taiwan Environmental Protection Administration (8 hr-CO2: 1000 ppm) and the air quality guideline of Hong Kong Environmental Protection Department (1 hr-CO2: 2500 ppm for Level 1 for buses). Observations also showed that high-capacity tour bus cabins with air conditioning system operating in recirculation mode are severely lacking in air exchange rate, which may negatively impact transportation safety. Moreover, the passenger zones were able to maintain a temperature of between 20 and 25°C during travel, which effectively suppresses the dispersion of volatile organic compounds. Finally, the authors suggest that in the journey, increasing the ventilation frequency of tour bus cabin, which is very beneficial to maintain the travel safety and enhance the quality of travel. PMID:25923722

Absorption enhancement and sensing properties of Ag diamond nanoantenna arrays

NASA Astrophysics Data System (ADS)

Yuan, Yu-Yang; Yuan, Zong-Heng; Li, Xiao-Nan; Wu, Jun; Zhang, Wen-Tao; Ye, Song

2015-07-01

Noble metal nanoantenna could effectively enhance light absorption and increase detection sensitivity. In this paper, we propose a periodic Ag diamond nanoantenna array to increase the absorption of thin-film solar cells and to improve the detection sensitivity via localized surface plasmon resonance. The effect of nanoantenna arrays on the absorption enhancement is theoretically investigated using the finite difference time domain (FDTD) method with manipulating the spectral response by geometrical parameters of nanoantennas. A maximum absorption enhancement factor of 1.51 has been achieved in this study. In addition, the relation between resonant wavelength (intensity reflectivity) and refractive index is discussed in detail. When detecting the environmental index using resonant wavelengths, a maximum detection sensitivity of about 837 nm/RIU (refractive index unit) and a resolution of about 10-3 RIU can be achieved. Moreover, when using the reflectivity, the sensitivity can be as high as 0.93 AU/RIU. Furthermore, we also have theoretically studied the effectiveness of nanoantennas in distinguishing chemical reagents, solution concentrations, and solution allocation ratios by detecting refractive index. From the results presented in this paper, we conclude that this work might be useful for biosensor detection and other types of detections. Project supported by the International Scientific and Technological Cooperation Projects of Guizhou Province, China (Grant No. 20117035) and the Program for Innovative Research Team of Guilin University of Electronic Technology, China (Grant No. IRTGUET).

Water-quality assessment of the Rio Grande Valley, Colorado, New Mexico and Texas; ground-water quality in the Rio Grande flood plain, Cochiti Lake, New Mexico, to El Paso, Texas, 1995

USGS Publications Warehouse

Bexfield, L.M.; Anderholm, S.K.

1997-01-01

From March to May of 1995, water samples were collected from 30 wells located in the flood plain of the Rio Grande between Cochiti Lake, New Mexico, and El Paso, Texas. These samples were analyzed for a broad host of constituents, including field parameters, major constituents, nutrients, dissolved organic carbon, trace elements, radiochemicals, pesticides, and volatile organic compounds. The main purpose of this study was to observe the quality of ground water in this part of the Rio Grande Valley study unit of the U.S. Geological Survey National Water-Quality Assessment program. The sampling effort was limited to the basin- fill aquifer beneath the above-defined reach of the Rio Grande flood plain because of the relative homogeneity of the hydrogeology, the large amount of ground-water use for public supply, and the potential for land-use activities to affect the quality of ground water. Most of the wells sampled for the study are used for domestic purposes, including drinking water. Depths to the tops of the sampling intervals in the 30 wells ranged from 10 to 345 feet below land surface, and the median was 161.5 feet; the sampling intervals in most of the wells spanned about 10 feet or less. Quality-control data were collected at three of the wells. A significant amount of variation was found in the chemical composition of ground water sampled throughout the study area, but the water generally was found to be of suitable chemical quality for use as drinking water, according to current enforceable standards established by the U.S. Environmental Protection Agency (EPA). Nutrients generally were measured at concentrations near or below their method reporting limits. The most dominant nutrient species was nitrite plus nitrate, at a maximum concentration of 1.9 milligrams per liter (as N). Only eight of the trace elements analyzed for had median concentrations greater than their respective minimum reporting levels. Water from one well exceeded the lifetime health advisory established by the EPA for molybdenum; water from a different well exceeded the proposed EPA maximum contaminant level for uranium. Gross alpha and gross beta particle activities generally appeared to strongly correlate with quantities of uranium and potassium, respectively, detected in ground water. However, water from one well exceeded the EPA maximum contaminant level for gross alpha particle activity and may exceed the EPA maximum contaminant level for beta particle and photon activity, although current data on gross beta particle activities are not conclusive on this point. Radon concentrations did not appear to directly correlate with uranium concentrations. The herbicide prometon was the only synthetic organic compound detected in ground water in the study area, and was detected in only one well, at a concentration of 0.038 microgram per liter. This well is shallow and is not used for drinking water. With the exception of the one detection of prometon, no strong evidence was found of effects on ground-water quality from human activities. Therefore, most of the water sampled probably recharged at the margins of the alluvial basins or recharged through the flood plain before human development began. With respect to major constituents, the concentrations of dissolved solids ranged from 209 to 3,380 milligrams per liter, and the median concentration was 409.5 milligrams per liter. There is evidence that the overall chemical composition of ground water in the study area may be affected by several processes, including cation exchange, feldspar weathering, calcite dissolution and precipitation, dissolution of volcanic glass, and microbial activity. Several chemical constituents in ground water showed relatively distinct spatial patterns that appear to be related to one or more of these processes.

Organochlorine pesticide residues in bed sediments of the San Joaquin River and its tributary streams, California

USGS Publications Warehouse

Gilliom, R.J.; Clifton, D.G.

1987-01-01

The distribution and concentrations of organochlorine pesticide residues in bed sediments were assessed from samples collected at 24 sites in the San Joaquin River and its tributaries in the San Joaquin Valley, California. Sampling was designed to collect the finest grained bed sediments present in the vicinity of each site. One or more of the 14 pesticides analyzed were detected at every site. Pesticides detected at one or more sites were chlordane, DDD, DDE, DDT, dieldrin, endosulfan, mirex, and toxaphene. Pesticides not detected were endrin, heptachlor, heptachlor epoxide, lindane, methoxychlor, and perthane. The most frequently detected pesticides were DDD (83% of sites), DDE (all sites), DDT (33% of sites), and dieldrin (58% of sites). Maximum concentrations of these pesticides, which were correlated with each other and with the amount of organic carbon in the sample, were DDD, 260 micrograms/kg; DDE, 430 micrograms/kg; DDT, 420 micrograms/kg; and dieldrin, 8.9 micrograms/kg. Six small tributary streams that drain agricultural areas west of the San Joaquin River had the highest concentrations. Water concentrations and loads were estimated for each pesticide from its concentration in bed sediments, the concentration of suspended sediment, and streamflow. Estimated loadings of DDD, DDE, DDT, and dieldrin from tributaries to the San Joaquin River indicate that most of the loading to the river at the time of the study was probably from the westside tributaries. Estimated water concentrations exceeded the aquatic life criterion for the sum of DDD, DDE, and DDt of 0.001 microgram/L at nine of the 24 sites sampled. Five of the nine sites are westside tributaries and one is the San Joaquin River near Vernalis. (Author 's abstract)

Maternal Buprenorphine Dose, Placenta Buprenorphine and Metabolite Concentrations and Neonatal Outcomes

PubMed Central

Concheiro, Marta; Jones, Hendreé E.; Johnson, Rolley E.; Choo, Robin; Shakleya, Diaa M.; Huestis, Marilyn A.

2010-01-01

Buprenorphine is approved as pharmacotherapy for opioid dependence in non-pregnant patients in multiple countries, and is currently under investigation for pregnant women in the US and Europe. This research evaluates the disposition of buprenorphine, opiates, cocaine, and metabolites in 5 term placentas from a US cohort. Placenta and matched meconium concentrations were compared, and relationships between maternal buprenorphine dose, placenta concentrations, and neonatal outcomes following controlled administration during gestation were investigated. Buprenorphine and/or metabolites were detected in all placenta specimens and were uniformly distributed across this tissue (CV<27.5%, 4 locations), except for buprenorphine in 3 placentas. In 2 of these, buprenorphine was not detected in some locations and, in the 3rd placenta, was totally absent. Median (range) concentrations were buprenorphine 1.6ng/g (not detected to 3.2), norbuprenorphine 14.9ng/g (6.2 to 24.2), buprenorphine-glucuronide 3ng/g (1.3 to 5.0) and norbuprenorphine-glucuronide 14.7ng/g (11.4 to 25.8). Placenta is a potential alternative matrix for detecting in utero buprenorphine exposure, but at lower concentrations (15–70 fold) than in meconium. Statistically significant correlations were observed for mean maternal daily dose from enrollment to delivery and placenta buprenorphine-glucuronide concentration, and for norbuprenorphine-glucuronide concentrations and time to neonatal abstinence syndrome (NAS) onset and duration, and for norbuprenorphine/norbuprenorphine-glucuronide ratio and maximum NAS score, and newborn length. Analysis of buprenorphine and metabolites in this alternative matrix, an abundant waste product available at the time of delivery, may be valuable for prediction of neonatal outcomes for clinicians treating newborns of buprenorphine-exposed women. PMID:20216119

Ground-water-quality assessment of the Central Oklahoma aquifer, Oklahoma; hydrologic, water-quality, and quality-assurance data 1987-90

USGS Publications Warehouse

Ferree, D.M.; Christenson, S.C.; Rea, A.H.; Mesander, B.A.

1992-01-01

This report presents data collected from 202 wells between June 1987 and September 1990 as part of the Central Oklahoma aquifer pilot study of the National Water-Quality Assessment Program. The report describes the sampling networks, the sampling procedures, and the results of the ground-water quality and quality-assurance sample analyses. The data tables consist of information about the wells sampled and the results of the chemical analyses of ground water and quality-assurance sampling. Chemical analyses of ground-water samples in four sampling networks are presented: A geochemical network, a low-density survey bedrock network, a low-density survey alluvium and terrace deposits network, and a targeted urban network. The analyses generally included physical properties, major ions, nutrients, trace substances, radionuclides, and organic constituents. The chemical analyses of the ground-water samples are presented in five tables: (1) Physical properties and concentrations of major ions, nutrients, and trace substances; (2) concentrations of radionuclides and radioactivities; (3) carbon isotope ratios and delta values (d-values) of selected isotopes; (4) concentrations of organic constituents; and (5) organic constituents not reported in ground-water samples. The quality of the ground water sampled varied substantially. The sum of constituents (dissolved solids) concentrations ranged from 71 to 5,610 milligrams per liter, with 38 percent of the wells sampled exceeding the Secondary Maximum Contaminant Level of 500 milligrams per liter established under the Safe Drinking Water Act. Values of pH ranged from 5.7 to 9.2 units with 20 percent of the wells outside the Secondary Maximum Contaminant Level of 6.5 to 8.5 units. Nitrite plus nitrate concentrations ranged from less than 0.1 to 85 milligrams per liter with 8 percent of the wells exceeding the proposed Maximum Contaminant Level of 10 milligrams per liter. Concentrations of trace substances were highly variable, ranging from below the reporting level to concentrations over the Maximum Contaminant Levels for several constituents (arsenic, barium, cadmium, chromium, lead, and selenium). Radionuclide activities also were highly variable. Gross alpha radioactivity ranged from 0.1 to 210 picocuries per liter as 230thorium. Of the wells sampled, 20 percent exceeded the proposed Maximum Contaminant Level of 15 picocuries per liter for gross alpha radioactivity. Organic constituents were detected in 39 percent of the 170 wells sampled for organic constituents; in most cases concentrations were at or near the laboratory minimum reporting levels. Ten of the wells sampled for organic constituents had one or more constituents (chlordane, dieldrin, heptachlor epoxide, trichloroethylene, 1,1-dichloroethylene, 1,1,1-trichloroethane) at concentrations equal to or greater than the Maximum Contaminant Level or acceptable concentrations as suggested in the Environmental Protection Agency's Health Advisory Summaries. Quality-assurance sampling included duplicate samples, repeated samples, blanks, spikes, and blind samples. These samples proved to be essential in evaluating the accuracy of the data, particularly in the case of volatile organic constituents.

Method for analysis dried vine fruits contaminated with ochratoxin A.

PubMed

Galvis-Sánchez, Andrea C; Barros, Antonio S; Delgadillo, Ivonne

2008-06-09

The EU maximum limit of 10 microg kg(-1) of OTA for dried vine fruits has been established since 2002 (European Commission, 2005). The presented work explore the capability of using Fourier infrared spectroscopy attenuated total reflection (FTIR-ATR) for the detection of ochratoxin A (OTA) in dried vine fruits in a range of concentration between 2 and 50 microg kg(-1) OTA. The method developed included a sample pretreatment using a C18 cartridge which was efficient for the isolation of the mycotoxin. The PLS1 analysis of the spectrum of sultanas spiked with different OTA concentrations showed a good correlation between the spectral data and reference concentration for OTA (R(2)=0.85).

Experimental measurements of the ground cloud effluents and cloud growth for the May 20, 1975, Titan 3C launch at Air Force Eastern Test Range, Florida

NASA Technical Reports Server (NTRS)

Gregory, G. L.; Storey, R. W., Jr.

1977-01-01

The experiment included surface level and airborne in situ cloud measurements of the exhaust effluents from the Titan IIIC solid rocket boosters. Simultaneous visible spectrum photographic pictures of the ground cloud as well as infrared imaging of the cloud were obtained to study the cloud rise, growth, and direction of travel within the earth's surface mixing layer. The NASA multilayer diffusion model predictions of cloud growth, direction of travel, and expected surface level effluent concentrations were made prior to launch and after launch using measured meteorological conditions. Prelaunch predictions were used to position the effluent monitoring instruments, and the postlaunch predictions were compared with the measured data. Measurement results showed that surface level effluent values were low, often below the detection limits of the instrumentation. The maximum surface level hydrogen chloride concentration measured 50 parts per billion at about 8 km from the launch pad. The maximum observed in-cloud (airborne measurement) hydrogen chloride concentration was 7 per million.

Seasonal determination of trace and ultra-trace content in Macrocystis pyrifera from San Jorge Gulf (Patagonia) by Total Reflection X-ray Fluorescence

NASA Astrophysics Data System (ADS)

Salomone, Vanesa N.; Riera, Marina; Cerchietti, Luciana; Custo, Graciela; Muniain, Claudia

2017-05-01

Seaweed have a great capacity to accumulate heavy metals in their tissues. The chemical characterization of seaweed is important due to their use in environmental monitoring and human or animal food. The aim of the present study was to evaluate the multi-elemental composition of seaweed from San Jorge Gulf (Patagonia, Argentina) by Total Reflection X-ray Fluorescence (TXRF). The elements As, Br, Cu, Cr, Fe, Mn, Ni, Pb, Rb, Sr, V and Zn were seasonally analyzed and quantified in blades of Macrocystis pyrifera. TXRF showed to be a suitable technique for simultaneous multi-element analysis in this kind of samples. The results revealed seasonal variations in the chemical content for some elements; arsenic content was maximum in summer and autumn, iron concentration increased to the winter and zinc concentration was maximum in autumn. The sum of principal micronutrients (Fe + Zn + Mn + Cu) varied between 114 and 171 mg k- 1 g dw. The total As concentration ranged between 36 and 66 mg kg- 1. Lead, nickel and copper were not detected.

Dissolved pesticide concentrations entering the Sacramento-San Joaquin Delta from the Sacramento and San Joaquin Rivers, California, 2012-13

USGS Publications Warehouse

Orlando, James L.; McWayne, Megan; Sanders, Corey; Hladik, Michelle

2014-01-01

Surface-water samples were collected from the Sacramento and San Joaquin Rivers where they enter the Sacramento–San Joaquin Delta, and analyzed by the U.S. Geological Survey for a suite of 99 current-use pesticides and pesticide degradates. Samples were collected twice per month from May 2012 through July 2013 and from May 2012 through April 2013 at the Sacramento River at Freeport, and the San Joaquin River near Vernalis, respectively. Samples were analyzed by two separate laboratory methods by using gas chromatography with mass spectrometry or liquid chromatography with tandem mass spectrometry. Method detection limits ranged from 0.9 to 10.5 nanograms per liter (ng/L). A total of 37 pesticides and degradates were detected in water samples collected during the study (18 herbicides, 11 fungicides, 7 insecticides, and 1 synergist). The most frequently detected pesticides overall were the herbicide hexazinone (detected in 100 percent of the samples); 3,4-dichloroaniline (97 percent), which is a degradate of the herbicides diuron and propanil; the fungicide azoxystrobin (83 percent); and the herbicides diuron (72 percent), simazine (66 percent), and metolachlor (64 percent). Insecticides were rarely detected during the study. Pesticide concentrations varied from below the method detection limits to 984 ng/L (hexazinone). Twenty seven pesticides and (or) degradates were detected in Sacramento River samples, and the average number of pesticides per sample was six. The most frequently detected compounds in these samples were hexazinone (detected in 100 percent of samples), 3,4-dichloroaniline (97 percent), azoxystrobin (88 percent), diuron (56 percent), and simazine (50 percent). Pesticides with the highest detected maximum concentrations in Sacramento River samples included the herbicide clomazone (670 ng/L), azoxystrobin (368 ng/L), 3,4-dichloroaniline (364 ng/L), hexazinone (130 ng/L), and propanil (110 ng/L), and all but hexazinone are primarily associated with rice agriculture. In addition to the twice monthly sampling, surface-water samples were collected from the Sacramento River on 5 consecutive days following a rainfall event in the Sacramento urban area. Samples collected following this event contained an average of 11 pesticides. The insecticides carbaryl, fipronil, and imidacloprid; the herbicide DCPA; and the fungicide imazalil were only detected in the Sacramento River during this storm-runoff event, and two detections of fipronil during this period exceeded the U.S. Environmental Protection Agency Aquatic Life Benchmark (11 ng/L) for chronic toxicity to invertebrates in freshwater. In San Joaquin River samples, 26 pesticides and (or) degradates were detected, and the average number detected per sample was 9. The most frequently detected compounds in these samples were hexazinone and metolachlor (detected in 100 percent of samples); diuron (96 percent); the fungicide boscalid (96 percent); the degradates 3,4-dicloroaniline (92 percent) and NN-(3,4-Dichlorophenyl)-N’-methylurea (DCPMU; 83 percent); simazine (83 percent); and azoxystrobin (75 percent). The pesticides with the highest detected maximum concentrations were hexazinone (984 ng/L), diuron (695 ng/L), simazine (524 ng/L), the herbicide prometryn (155 ng/L), metolachlor (127 ng/L), boscalid (112 ng/L), DCPMU (111 ng/L), and the herbicide pendimethalin (108 ng/L).

Quality of water in domestic wells in the Chicot and Chicot equivalent aquifer systems, southern Louisiana and southwestern Mississippi, 2000-2001

USGS Publications Warehouse

Tollett, Roland W.; Fendick, Robert B.; Simmons, Lane B.

2003-01-01

In 2000-2001, water-quality data were collected from 60 randomly selected domestic wells in the Acadian-Pontchartrain Study Unit, as part of the National Water-Quality Assessment Program. The data were collected from wells screened in shallow sands (less than 350 feet below land surface) in two major aquifer systems--the Chicot aquifer system in southwestern Louisiana and the Chicot equivalent aquifer system in southeastern Louisiana and southwestern Mississippi. The Chicot equivalent aquifer system is part of the Southern Hills regional aquifer system, and both the Chicot aquifer system and the Southern Hills regional aquifer systems are designated as sole-source aquifers by the U.S. Environmental Protection Agency (USEPA). The well depths ranged from 40 to 340 feet below land surface with a median depth of 120 feet. The ground-water-quality data included 5 physiochemical properties, dissolved solids, 9 major inorganic ions, 24 trace elements, 6 nutrients, dissolved organic carbon, 109 pesticides and degradation products, and 85 volatile organic compounds (VOC's); and a subset of the wells were sampled for radon, chlorofluorocarbons, and stable isotopes. Water from 35 of the 60 domestic wells sampled had pH values less than the USEPA Seconday Maximum Contaminant Level (SMCL) range of 6.5 to 8.5 standard units. Specific conductance ranged from 17 to 1,420 microsiemens per centimeter at 25 degrees Celsius. Dissolved-solids concentrations in water from two wells exceeded the SMCL of 500 mg/L (milligrams per liter); the maximum concentration was 858 mg/L. Sodium and calcium were the dominant cations, and bicarbonate and chloride were the dominant anions. One chloride concentration (264 mg/L) exceeded the SMCL of 250 mg/L. One arsenic concentration (55.3 micrograms per liter) exceeded the USEPA Maximum Contaminant Level (MCL) of 10 micrograms per liter. Iron concentrations in water from 22 wells exceeded the SMCL of 300 micrograms per liter; the maximum concentration was 8,670 micrograms per liter. Manganese concentrations in water from 26 wells exceeded the SMCL of 50 micrograms per liter; the maximum concentration was 481 micrograms per liter. Health Advisories have been established for six of the trace elements analyzed; no concentrations were greater than these nonenforceable standards. Radon concentrations in water from 9 of 50 wells sampled were greater thanthe proposed USEPA MCL of 300 picocuries per liter. Concentrations of ammonia, ammonia plus organic nitrogen, and nitrite plus nitrate in water from four wells were greater than 2 mg/L, a level that might indicate anthropogenic influences. The median dissolved organic carbon concentration was an estimated 0.30 mg/L, which indicated naturally occurring dissolved organic carbon conditions in the study area. Eight pesticides and two degradation products were detected in water from five wells. Twenty-four VOC's were detected in water from 44 wells. All concentrations of pesticides and VOC's were less than USEPA drinking-water standards. Quality-control samples, which included field-blank samples, replicates, and field and laboratory spikes, indicated no bias in ground-water data from collection procedures or analyses. VAriance between the environmental sampls and he corresponding replicate samples was typically less than 5 percent, indicating and acceptable degree of laboratory precision and data collection reproducibility. The Mann-Whitney rank-sum test was used to compare depth to top of screen and selected physicochemical properties and chemical constituents between six groups of wells. Values for selected physicochemical and chemical constituents were typically greater in wells located in the Chicot aquifer system than in the Chicot equivalent aquifer system. Values for specific conductance, pH, calcium, sodium, bicarbonate, chloride, dis

Validation of the LacTek test applied to spiked extracts of tissue samples: determination of performance characteristics.

PubMed

Mitchell, J M; Yee, A J; McNab, W B; Griffiths, M W; McEwen, S A

1999-01-01

LacTek tests are competitive enzyme-linked immunosorbent assays intended for rapid detection of antimicrobial residues in bovine milk. In this study, the LacTek test protocol was modified for use with extracts of bovine tissue to detect beta-lactam, tetracycline, and sulfamethazine residues. Test performance characteristics--precision, accuracy, ruggedness, practicability, and analytical specificity and sensitivity--were investigated. Results suggest that LacTek tests can be easily adapted to detect antimicrobial residues in extracts of lean ground beef. However, positive samples may not contain residues at violative concentrations (i.e., Canadian maximum residue limits), and therefore, additional analysis would be required for final confirmation and quantitation (e.g., chromatography).

Assessing atmospheric concentration of polychlorinated biphenyls (PCBs) by evergreen Rhododendron maximum next to a contaminated stream

USGS Publications Warehouse

Dang, Viet D.; Walters, David; Lee, Cindy M.

2016-01-01

Conifers are often used as an “air passive sampler”, but few studies have focused on the implication of broadleaf evergreens to monitor atmospheric semivolatile organic compounds such as polychlorinated biphenyls (PCBs). In this study, we used Rhododendron maximum (rhododendron) growing next to a contaminated stream to assess atmospheric PCB concentrations. The study area was located in a rural setting and approximately 2 km downstream of a former Sangamo-Weston (S-W) plant. Leaves from the same mature shrubs were collected in late fall 2010, and winter and spring 2011. PCBs were detected in the collected leaves suggesting that rhododendron can be used as air passive samplers in rural areas where active sampling is impractical. Estimated ΣPCB (47 congeners) concentrations in the atmosphere decreased from fall 2010 to spring 2011 with concentration means at 3990, 2850, and 931 pg m-3 in fall 2010, winter 2011, and spring 2011, respectively. These results indicate that the atmospheric concentrations at this location continue to be high despite termination of active discharge from the former S-W plant. Leaves had a consistent pattern of high concentrations of tetra- and penta-CBs similar to the congener distribution in polyethylene (PE) passive samplers deployed in the water column suggesting that volatilized PCBs from the stream were the primary source of contaminants in rhododendron leaves.

Concentration of Trichloroethylene in Breast Milk and Household Water from Nogales, Arizona

PubMed Central

Beamer, Paloma I.; Luik, Catherine E.; Abrell, Leif; Campos, Swilma; Martínez, María Elena; Sáez, A. Eduardo

2013-01-01

The United States Environmental Protection Agency has identified quantification of trichloroethylene (TCE), an industrial solvent, in breast milk as a high priority need for risk assessment. Water and milk samples were collected from 20 households by a lactation consultant in Nogales, Arizona. Separate water samples (including tap, bottled and vending machine) were collected for all household uses: drinking, bathing, cooking, and laundry. A risk factor questionnaire was administered. Liquid-liquid extraction with diethyl ether was followed by GC-MS for TCE quantification in water. Breast milk underwent homogenization, lipid hydrolysis and centrifugation prior to extraction. The limit of detection was 1.5 ng/mL. TCE was detected in 7 of 20 mothers’ breast milk samples. The maximum concentration was 6 ng/mL. TCE concentration in breast milk was significantly correlated with the concentration in water used for bathing (ρ=0.59, p=0.008). Detection of TCE in breast milk was more likely if the infant had a body mass index <14 (RR=5.2, p=0.02). Based on average breast milk consumption, TCE intake for 5% of the infants may exceed the proposed US EPA Reference Dose. Results of this exploratory study warrant more in depth studies to understand risk of TCE exposures from breast milk intake. PMID:22827160

Relevance of drinking water as a source of human exposure to bisphenol A.

PubMed

Arnold, Scott M; Clark, Kathryn E; Staples, Charles A; Klecka, Gary M; Dimond, Steve S; Caspers, Norbert; Hentges, Steven G

2013-03-01

A comprehensive search of studies describing bisphenol A (BPA) concentrations in drinking water and source waters (i.e., surface water and groundwater) was conducted to evaluate the relevance of drinking water as a source of human exposure and risk. Data from 65 papers were evaluated from North America (31), Europe (17), and Asia (17). The fraction of drinking water measurements reported as less than the detection limit is high; 95%, 48%, and 41%, for North America, Europe, and Asia, respectively. The maximum quantified (in excess of the detection limit) BPA concentrations from North America, Europe, and Asia are 0.099 μg/l, 0.014 μg/l, and 0.317 μg/l. The highest quantified median and 95th percentile concentrations of BPA in Asian drinking water are 0.026 μg/l and 0.19 μg/l, while high detection limits restricted the determination of representative median and 95th percentile concentrations in North America and Europe. BPA in drinking water represents a minor component of overall human exposure, and compared with the lowest available oral toxicity benchmark of 16 μg/kg-bw/day (includes an uncertainty factor of 300) gives margins of safety >1100. Human biomonitoring data indicate that ingestion of drinking water represents <2.8% of the total intake of BPA.

Determination of Cerium (IV) Using Rhodamine 6G Fluorescence Quenching

NASA Astrophysics Data System (ADS)

Zhao, Zh.; Sheng, L.; Su, B.; Tao, C.; Jing, W.

2017-11-01

The interaction between rhodamine 6G (Rh6G) and cerium sulfate was studied by the fluorescence quenching method. In a sulfuric acid medium, the interaction of Ce(IV) with Rh6G results in Rh6G fluorescence quenching. The maximum excitation wavelength (λex) and the maximum emission wavelength (λem) are 530 nm and 555 nm, respectively. A good linearity between the relative fl uorescence intensity (ΔF) and Ce(IV) was observed in the range 0.12-1.08 μg/mL. The detection limit was 1.4 × 10-3 μg/mL. The optimum reaction conditions, influencing factors, and effect of coexisting substances were investigated in the experiment. We found that the concentration of Rh6G was 3.2 × 10-6 mol/L, and the fl uorescence intensity was maximum.

Species characteristics of lead in sea foods collected from coastal water of Fujian, Southeastern of China.

PubMed

He, Ye; Chen, Zhiqiang; Mo, Fan; Huang, Limei; Xu, LiangJun; Wu, Yongning; Xue, Zhimin; Fu, FengFu

2016-09-14

Various sea foods including fish, shellfish and shrimp were collected from different coastal areas of Fujian in China, and their Pb species characteristics were investigated in detail. The results indicated that there are two different species characteristics of Pb existing in sea food samples. About half of samples were detected to have only Pb(2+), and another half of samples were detected to have both Pb(2+) and trimethyl lead (TML). The results also revealed that Pb species characteristics in the sea foods rather depend on the species of sea food than the sampling area. In comparison with shellfish/shrimp samples, fish samples have higher concentrations of TML and Pb(2+). Especially, the average concentration of TML in the TML-detected fish samples is about 3 times of that in the TML-detected shellfish/shrimp samples, indicating that fish has stronger ability to uptake and accumulate TML. The concentrations of total lead in all samples are lower than the maximum allowable limit of national standard, suggesting that the sea foods collected from Fujian are safe for consumption. By considering that TAL has more toxicity than Pb(2+), the effect of TML in sea foods on the human health should be paid more attention in the future.

Robust experimental design for optimizing the microbial inhibitor test for penicillin detection in milk.

PubMed

Nagel, O G; Molina, M P; Basílico, J C; Zapata, M L; Althaus, R L

2009-06-01

To use experimental design techniques and a multiple logistic regression model to optimize a microbiological inhibition test with dichotomous response for the detection of Penicillin G in milk. A 2(3) x 2(2) robust experimental design with two replications was used. The effects of three control factors (V: culture medium volume, S: spore concentration of Geobacillus stearothermophilus, I: indicator concentration), two noise factors (Dt: diffusion time, Ip: incubation period) and their interactions were studied. The V, S, Dt, Ip factors and V x S, V x Ip, S x Ip interactions showed significant effects. The use of 100 microl culture medium volume, 2 x 10(5) spores ml(-1), 60 min diffusion time and 3 h incubation period is recommended. In these elaboration conditions, the penicillin detection limit was of 3.9 microg l(-1), similar to the maximum residue limit (MRL). Of the two noise factors studied, the incubation period can be controlled by means of the culture medium volume and spore concentration. We were able to optimize bioassays of dichotomous response using an experimental design and logistic regression model for the detection of residues at the level of MRL, aiding in the avoidance of health problems in the consumer.

Fate of selected pesticides, estrogens, progestogens and volatile organic compounds during artificial aquifer recharge using surface waters.

PubMed

Kuster, Marina; Díaz-Cruz, Silvia; Rosell, Mònica; López de Alda, Miren; Barceló, Damià

2010-05-01

The artificial recharge of aquifers has become a valuable tool to increase water resources for drinking water production in many countries. In this work a total of 41 organic pollutants belonging to the classes of pesticides, estrogens, progestogens and volatile organic compounds (VOCs) have been monitored in the water from two artificial recharge plants located in Sweden and Denmark. The results from two sampling campaigns performed in each plant indicate good chemical status of the source water, as the contaminants detected were present at very low levels, far from those established in the legislation as maximum admissible concentrations (when existing) and far from those considered as a risk. Thus, of the 17 pesticides investigated, BAM (2,6-dichlorobenzamide), desethylatrazine, simazine, atrazine, terbuthylazine, diuron, metolachlor, and diazinon were the only compounds detected, and total pesticides levels were below 25ng L(-1), respectively. Estrone-3-sulfate was the only estrogen detected, at concentrations lower than 0.5ng L(-1). Progestogens were not found in any sample. Detected VOCs (benzene, toluene, ethylbenzene, and trichloroethylene) were below 0.04microg L(-1). The efficiency of elimination of these organic contaminants was poor as no significant decrease in their concentrations was observed through the recharge process.

Multispectral photoacoustic decomposition with localized regularization for detecting targeted contrast agent

NASA Astrophysics Data System (ADS)

Tavakoli, Behnoosh; Chen, Ying; Guo, Xiaoyu; Kang, Hyun Jae; Pomper, Martin; Boctor, Emad M.

2015-03-01

Targeted contrast agents can improve the sensitivity of imaging systems for cancer detection and monitoring the treatment. In order to accurately detect contrast agent concentration from photoacoustic images, we developed a decomposition algorithm to separate photoacoustic absorption spectrum into components from individual absorbers. In this study, we evaluated novel prostate-specific membrane antigen (PSMA) targeted agents for imaging prostate cancer. Three agents were synthesized through conjugating PSMA-targeting urea with optical dyes ICG, IRDye800CW and ATTO740 respectively. In our preliminary PA study, dyes were injected in a thin wall plastic tube embedded in water tank. The tube was illuminated with pulsed laser light using a tunable Q-switch ND-YAG laser. PA signal along with the B-mode ultrasound images were detected with a diagnostic ultrasound probe in orthogonal mode. PA spectrums of each dye at 0.5 to 20 μM concentrations were estimated using the maximum PA signal extracted from images which are obtained at illumination wavelengths of 700nm-850nm. Subsequently, we developed nonnegative linear least square optimization method along with localized regularization to solve the spectral unmixing. The algorithm was tested by imaging mixture of those dyes. The concentration of each dye was estimated with about 20% error on average from almost all mixtures albeit the small separation between dyes spectrums.

[Levels of Ochratoxin A and total Aflatoxins in Panamanian exportation coffee by an ELISA Method].

PubMed

Franco, Heriberto; Vega, Aracelly; Reyes, Stephany; De Léon, Javier; Bonilla, Alexis

2014-03-01

A study about processing conditions of exportation coffee in 15 benefits located in Chiriqui, western region of Panama, was conducted. In addition, 21 samples of processed coffee (green beans), from the benefits, were analyzed. The samples were microbiologically tested in order to quantify total aflatoxins (B1, B2, G1 and G2) and Ochratoxin A (OTA), using the immunoaffinity ELISA method. A detection limit of 0.017 ng/mL, was determined for Ochratoxin A, which is equivalent to a concentration of 0.829 µg/kg, and a detection limit of 0.027 ng/mL, for total aflatoxins, which is equivalent to a concentration of 1.350 µg/kg. It was found that four (19%) out of the 21 samples were positive to the presence of Ochratoxin A and three (14%) to the presence of total aflatoxins. Samples showed levels of Ochratoxin A in the range 4.90 - 37.73 µg/kg; only three of them exceeded the maximum limit allowed by the European Union, for the concentration of Ochratoxin, which is of 5.0 µg/kg. Total aflatoxins were found in the range 1.51 - 1.93 µg/kg, below 10 µg/kg which is the maximum limit allowed for coffee by the European Union. The results indicate that the processing of coffee produced in Panama successfully meets international standards for postharvest handling, which leads to a low incidence ofmycotoxins and very low levels ofmycotoxin-producing fungi.

Quality of ground water in the Biscayne Aquifer in Miami-Dade, Broward, and Palm Beach counties, Florida, 1996-1998, with emphasis on contaminants

USGS Publications Warehouse

Bradner, Anne; McPherson, Benjamin F.; Miller, Ronald L.; Kish, George; Bernard, Bruce

2005-01-01

The high permeability of the sand and limestone sediments and shallow water table of the Biscayne aquifer make ground water vulnerable to contamination by human activities. To assess potential contamination in the aquifer, untreated ground water was sampled from 30 public-supply wells (40-165 feet deep) in Broward, Miami-Dade, and Palm Beach Counties, 32 shallow wells (10-50 feet deep) in a recently urbanized (residential and light commercial) part of Broward County, and 3 shallow reference wells in Broward County. Results from sample analyses indicate that major ions, pH, dissolved oxygen, nutrients, and trace element concentrations were generally within the range indicative of background concentrations, except for: (1) substantially higher bromide concentrations in water from public-supply wells in southern Miami-Dade County; (2) a few relatively high (greater than 2 milligrams per liter) concentrations of nitrate in water from public-supply wells near agricultural lands in Miami-Dade and southern Broward Counties; and (3) a few relatively high concentrations of arsenic (greater than 10 micrograms per liter) in water from some shallow urban wells near golf courses. Pesticides were detected in every public-supply well, in most of the shallow, urban monitoring wells (78 percent), and in one reference well; however, no pesticide concentration exceeded any drinking-water standard. Fifteen different pesticides or their degradation products were detected. The most frequently detected pesticides were atrazine and tebuthiuron; less frequently detected were the herbicides diuron, fenuron, prometon, metolachlor, simazine, and 2,6-diethylaniline. Volatile organic compounds (VOCs) were detected in most of the public-supply wells (77 percent) and shallow, urban wells (91 percent) and in two of the three reference wells. Thirty-two different VOCs were detected in ground water in the Biscayne aquifer, with cis-1,2-dichloroethene the most frequently detected VOC in the public-supply wells, followed by methyl tert-butyl ether (MTBE), 1,4-dichlorobenzene, and chloroform. Toluene, p-isopropyltoluene, and 1,2,4-trimethylbenzene were the most frequently detected VOCs in the shallow, urban wells. Concentrations of all VOCs were less than the maximum contaminant level (MCL) for public drinking water, except in two samples from public-supply wells near industrialized areas that had vinyl chloride concentrations (3 and 5 micrograms per liter) above the MCL of 1 microgram per liter.

Inflammable Gas Mixture Detection with a Single Catalytic Sensor Based on the Electric Field Effect

PubMed Central

Tong, Ziyuan; Tong, Min-Ming; Meng, Wen; Li, Meng

2014-01-01

This paper introduces a new way to analyze mixtures of inflammable gases with a single catalytic sensor. The analysis technology was based on a new finding that an electric field on the catalytic sensor can change the output sensitivity of the sensor. The analysis of mixed inflammable gases results from processing the output signals obtained by adjusting the electric field parameter of the catalytic sensor. For the signal process, we designed a group of equations based on the heat balance of catalytic sensor expressing the relationship between the output signals and the concentration of gases. With these equations and the outputs of different electric fields, the gas concentration in a mixture could be calculated. In experiments, a mixture of methane, butane and ethane was analyzed by this new method, and the results showed that the concentration of each gas in the mixture could be detected with a single catalytic sensor, and the maximum relative error was less than 5%. PMID:24717635

Lead, cadmium and chromium in raw and boiled portions of Norway lobster.

PubMed

Perugini, Monia; Visciano, Pierina; Manera, Maurizio; Abete, Maria Cesarina; Tarasco, Renata; Amorena, Michele

2014-01-01

Lead, cadmium and chromium levels were determined in different raw and boiled portions of Norway lobster caught in the central Adriatic Sea (Italy). In raw specimens, the lowest concentrations were always detected in the white meat. Lead and cadmium content in the edible portion never exceeded the maximum levels set by European legislation. The highest cadmium and chromium values (0.47 ± 0.04 and 0.62 ± 0.13 mg/kg wet weight, respectively) were detected in the brown meat, while the highest lead concentrations were found in the exoskeleton (0.21 ± 0.01 mg/kg wet weight). Also, the boiled samples showed the lowest metal levels in the white meat, even if a significant increase (p < 0.01) was found for lead and cadmium compared to the corresponding raw portions. Among metals, chromium showed the highest concentrations in both raw and boiled portions, but up to now, the European legislation did not envisage any limits in seafood.

Environmental occurrence and shallow ground water detection of the antibiotic monensin from dairy farms

USGS Publications Warehouse

Watanabe, N.; Harter, T.H.; Bergamaschi, B.A.

2008-01-01

Pharmaceuticals used in animal feeding operations have been detected in various environmental settings. There is a growing concern about the impact on terrestrial and aquatic organisms and the development of antibiotic-resistant strains of microorganisms. Pharmaceutical use in milking cows is relatively limited compared with other livestock operations, except for the ionophore monensin, which is given to lactating cows as a feed. By weight, monensin can be the most significant antibiotic used in a dairy farm. This study investigates the potential of monensin to move from dairy operations into the surrounding ground water. Using two dairy farms in California as study sites, we twice collected samples along the environmental pathway-from flush lanes, lagoon waters, and shallow ground water beneath the dairies and beneath its associated manured fields. Monensin concentrations were determined using solid-phase extraction and liquid chromatography-tandem mass spectrometry with positive electrospray ionization. Monensin was detected in all of the flush lane and lagoon water samples. Theoretical maximum concentration estimated from the actual dosing rate and the theoretical excretion rate assuming no attenuation was one order of magnitude greater than observed concentrations, suggesting significant attenuation in the manure collection and storage system. Monensin was also detected, at levels ranging from 0.04 to 0.39 microg L(-1), in some of the ground water samples underneath the production area of the dairy but not from the adjacent manured fields. Concentrations in ground water immediately downgradient of the lagoons were one to two orders of magnitude lower than the concentrations detected in lagoons, suggesting attenuation in the subsurface. The data suggest the possibility of monensin transport into shallow (2-5 m) alluvial ground water from dairy management units, including manure storage lagoons and freestalls occupied by heifers, lactating cows, and dry cows.

Contrast-enhanced near-infrared laser mammography with a prototype breast scanner: feasibility study with tissue phantoms and preliminary results of imaging experimental tumors.

PubMed

Boehm, T; Hochmuth, A; Malich, A; Reichenbach, J R; Fleck, M; Kaiser, W A

2001-10-01

Near-infrared (NIR) optical mammography without contrast has a low specificity. The application of optical contrast medium may improve the performance. The concentration-dependent detectability of a new NIR contrast medium was determined with a prototype optical breast scanner. In vivo imaging of experimental tumors was performed. The NIR contrast agent NIR96010 is a newly synthesized, hydrophilic contrast agent for NIR mammography. A concentration-dependent contrast resolution was determined for tissue phantoms consisting of whole milk powder and gelatin. A central part of the phantoms measuring 2 x 2 cm2 without contrast was replaced with phantom material containing 1 micromol/L to 25 nmol/L NIR96010. The composite phantoms were measured with a prototype NIR breast scanner with lasers of lambda1 = 785 nm and lambda2 = 850 nm wavelength. Intensity profiles and standard deviations of the transmission signal in areas with and without contrast were determined by linear fit procedures. Signal-to-noise ratios and spatial resolution as a function of contrast concentration were determined. Near-infrared imaging of five tumor-bearing SCID mice (MX1 breast adenocarcinoma, tumor diameter 5-10 mm) was performed before and after intravenous application of 2 micromol/kg NIR96010. Spectrometry showed an absorption maximum of the contrast agent at 755 nm. No spectral shifts occurred in protein-containing solution. Signal-to-noise ratio in the transmission intensity profiles ranged from 1.1 at 25 nmol/L contrast to 28 at 1 micromol/L. At concentrations <40 nmol/L, no differentiation from the background was possible. The transitional area between the contrast-free edge of the phantom and the central contrast-containing part appeared in the profiles as a steep increase with a width of 4.2 +/- 1.8 mm. The experimental tumors were detectable in nonenhanced images as well as contrast-enhanced images, with better delineation after contrast administration. In postcontrast absorption profiles, a 44.1% +/- 11.3% greater absorption increase was seen in tumor tissue compared with normal tissue. The laser wavelength lambda1 of the prototype laser mammography device was not situated at maximum absorption of the contrast agent NIR96010 but on the descending shoulder of the absorption spectrum. This implies a 20% signal loss for contrast detection. Despite the nonideal measurement conditions, concentrations as low as 40 nmol/L were detectable in vitro. In vivo, all tumors were detectable in color-coded nonenhanced scans as well as in contrast-enhanced scans, with better delineation after contrast administration.

Chemical quality of precipitation at Greenville, Maine

USGS Publications Warehouse

Smath, J.A.; Potter, T.L.

1987-01-01

Weekly composite precipitation samples were collected at a rural site located in Greenville, Maine for analysis of trace metals and organic compounds. Samples collected during February 1982, through May 1984, were analyzed for cadmium, chromium, copper, lead, mercury, nickel, and zinc and during February 1982, through March 1983, for chlorinated hydrocarbon pesticides, pthalate ester plasticizers, and polychlorinated biphenyls. Deposition rates were computed. Data reported by the NADP (National Atmospheric Deposition Program) was used to evaluate the general chemical quality of the precipitation. The precipitation had relatively high concentrations of hydrogen ions, sulfate, and nitrate, compared to other constituents. Of the trace metals included for analysis, only copper, lead, and zinc were consistently detected. Lead concentrations exceeded the U.S. EPA recommended limit for domestic water supply in three samples. High deposition rates for some of the metals were episodic. Alpha-hexachlorocyclohexane was the only organic compound that was consistently detected (maximum 120 nanograms/L). None of the other organic compounds were detected in any of the samples. (Author 's abstract)

Potential diffusion of doramectin into a soil amended with female pig manure. A field experiment.

PubMed

Gil-Díaz, María Del Mar; Pérez-Sanz, Araceli; Martín, Margarita; Lobo, Maria Carmen

2011-10-12

Doramectin is a veterinary drug used as an antihelminthic and is excreted mainly in the feces as the nonmetabolized drug. This study investigated the time profile of doramectin excretion in pig feces and the potential transfer and persistence of doramectin in the soil when the pig manure is used as an organic amendment to the soil. The concentration of doramectin in feces peaked at 143.0 ng/g in the dry feces 4 days after treatment. On day 62, the drug was still detected in the pig feces. After the land application of pig manure, the maximum concentration of doramectin in soil (ppb level) was detected 6 days after treatment. Seven months after the manure application, traces of doramectin were detected in the soil from the surface to a depth of 90 cm. Successive applications of manure from pigs treated with doramectin in a specific area could produce an accumulation of this drug in the soil.

Occurrence of perchlorate in drinking water and seawater in South Korea.

PubMed

Her, Namguk; Jeong, Hyunchan; Kim, Jongsung; Yoon, Yeomin

2011-08-01

Concentrations of perchlorate were determined by both liquid-chromatography-mass spectrometry (LC-MS) and ion chromatography tandem mass spectrometry (IC-MS/MS) in 520 tap-water, 48 bottled-water, and 9 seawater samples obtained or purchased from >100 different locations in South Korea. The method detection limits were 0.013 μg/L for LC-MS and 0.005 μg/L for IC-MS/MS, and the limits of quantification (LOQs) were 0.10 μg/L for LC-MS and 0.032 μg/L for IC-MS/MS. Perchlorate was detected in most (80%) of the tap-water samples, with concentrations higher than the LOQ; the concentrations ranged from <1.0 to 6.1 μg/L (mean 0.56). Perchlorate was detected by IC-MS/MS in many (n = 23) of the bottled-water samples, with concentrations higher then the LOQ, ranging from 0.04 to 0.29 μg/L (mean 0.07 ± 0.01). The concentrations of perchlorate in all seawater samples collected from the various locations were higher than the LOQ, with a mean concentration of 1.15 ± 0.01 μg/L (maximum 6.11 and minimum 0.11). This study provides further evidence that drinking-water sources have been contaminated by perchlorate. To the best of our knowledge, this is the first comprehensive study on perchlorate assessment in drinking water and seawater in South Korea.

Hydrogeology and ground-water quality of northern Bucks County, Pennsylvania

USGS Publications Warehouse

Sloto, Ronald A.; Schreffler, Curtis L.

1994-01-01

Water from wells in the crystalline rocks has the lowest median pH (5.8), the lowest median specific conductance (139 microsiemens per centimeter), the lowest median alkalinity [16 mg/L (milligrams per liter) as CaCOg], and the highest dissolved oxygen concentration (9.0 mg/L) of the hydrogeologic units. Water from wells in carbonate rocks has the highest median pH (7.8) and the highest median alkalinity (195 mg/L as CaCO3) of the hydrogeologic units. Water from wells in the Lockatong Formation has the highest median specific conductance (428 microsiemens per centimeter) and the lowest dissolved oxygen concentration (0.8 mg/L) of the hydrogeologic units. Water from wells in crystalline rocks contains the lowest concentrations of total dissolved solids (TDS) of the hydrogeologic units. Water from the Lockatong Formation contains the highest concentration of TDS of the hydrogeologic units. Water from only 1 of 83 wells sampled exceeded the U.S. Environmental Protection Agency (USEPA) secondary maximum contaminant level (SMCL) for TDS; the well is in the Lockatong Formation. Five of 86 samples (6 percent) and 6 of 75 samples (8 percent) exceed the USEPA SMCL for iron and manganese, respectively. Nitrate is the most prevalent nitrogen species in ground water. The median nitrate concentration for all hydrogeologic units is 2.3 mg/L. Of 71 water samples from wells, no concentrations of nitrate exceed the USEPA maximum contaminant level. The median dissolved radon-222 activity was highest for water samples from wells in crystalline rock [3,600 pCi/L (picocuries per liter)] and lowest for water samples from wells in the Lockatong Formation (340 pCi/L) and diabase (350 pCi/L). Water samples for analysis for volatile organic compounds (VOC's) were collected from 34 wells in areas where the potential existed for the presence of VOC's in ground water. VOC's were detected in 23 percent of the 34 wells sampled. The most commonly detected compound was trichloroethylene (13 percent of sampled wells).

Occurrence, distribution and transport of pesticides into the Salton Sea Basin, California, 2001-2002

USGS Publications Warehouse

LeBlanc, L.A.; Kuivila, K.M.

2008-01-01

The Salton Sea is a hypersaline lake located in southeastern California. Concerns over the ecological impacts of sediment quality and potential human exposure to dust emissions from exposed lakebed sediments resulting from anticipated shrinking of shoreline led to a study of pesticide distribution and transport within the Salton Sea Basin, California, in 2001-2002. Three sampling stations-upriver, river mouth, and offshore-were established along each of the three major rivers that discharge into the Salton Sea. Large-volume water samples were collected for analysis of pesticides in water and suspended sediments at the nine sampling stations. Samples of the bottom sediment were also collected at each site for pesticide analysis. Sampling occurred in October 2001, March-April 2002, and October 2002, coinciding with the regional fall and spring peaks in pesticide use in the heavily agricultural watershed. Fourteen current-use pesticides were detected in water and the majority of dissolved concentrations ranged from the limits of detection to 151 ng/l. Diazinon, EPTC and malathion were detected at much higher concentrations (940-3,830 ng/l) at the New and Alamo River upriver and near-shore stations. Concentrations of carbaryl, dacthal, diazinon, and EPTC were higher in the two fall sampling periods, whereas concentrations of atrazine, carbofuran, and trifluralin were higher during the spring, which matched seasonal use patterns of these pesticides. Current-use pesticides were also detected on suspended and bed sediments in concentrations ranging from detection limits to 106 ng/g. Chlorpyrifos, dacthal, EPTC, trifluralin, and DDE were the most frequently detected pesticides on sediments from all three rivers. The number of detections and concentrations of suspended sediment-associated pesticides were often similar for the river upriver and near-shore sites, consistent with downstream transport of pesticides via suspended sediment. While detectable suspended sediment pesticide concentrations were more sporadic than detected aqueous concentrations, seasonal trends were similar to those for dissolved concentrations. Generally, the pesticides detected on suspended sediments were the same as those on the bed sediments, and concentrations were similar, especially at the Alamo River upriver site. With a few exceptions, pesticides were not detected in suspended or bed sediments from the off-shore sites. The partitioning of pesticides between water and sediment was not predictable from solely the physical-chemical properties of individual pesticide compounds, but appear to be a complicated function of the quantity of pesticide applied in the watershed, residence time of sediments in the water, and compound solubility and hydrophobicity. Sediment concentrations of most pesticides were found to be 100-1,000 times lower than the low-effects levels determined in human health risk assessment studies. However, maximum concentrations of chlorpyrifos on suspended sediments were approximately half the low-effects level, suggesting the need for further sediment characterization of lake sediments proximate to riverine inputs. ?? 2008 Springer Science+Business Media B.V.

Occurrence of fungicides and other pesticides in surface water, groundwater, and sediment from three targeted-use areas in the United States, 2009

USGS Publications Warehouse

Orlando, James L.; Smalling, Kelly L.; Reilly, Timothy J.; Boehlke, Adam; Meyer, Michael T.; Kuivila, Kathryn

2013-01-01

Surface-water, groundwater, and suspended- and bedsediment samples were collected in three targeted-use areas in the United States where potatoes were grown during 2009 and analyzed for an extensive suite of fungicides and other pesticides by gas chromatograph/mass spectrometry and liquid chromatography with tandem mass spectrometry. Fungicides were detected in all environmental matrices sampled during the study. The most frequently detected fungicides were azoxystrobin, boscalid, chlorothalonil, and pyraclostrobin. Other pesticides that were detected frequently included amino phosphonic acid (AMPA), atrazine, metolaclor, and the organochlorine insecticide p,p’-DDT and its degradates p,p’-DDD and p,p’-DDE. A greater number of pesticides were detected in surface water relative to the other environmental matrices sampled, and at least one pesticide was detected in 62 of the 63 surfacewater samples. The greatest numbers of pesticides and the maximum observed concentrations for most pesticides were measured in surface-water samples from Idaho. In eight surface- water samples (six from Idaho and two from Wisconsin), concentrations of bifenthrin, metolachlor, or malathion exceeded U.S. Environmental Protection Agency freshwater aquatic-life benchmarks for chronic toxicity to invertebrates. Thirteen pesticides, including seven fungicides, were detected in groundwater samples. Shallow groundwater samples collected beneath recently harvested potato fields contained more pesticides and had higher concentrations of pesticides than samples collected from other groundwater sources sampled during the study. Generally, pesticide concentrations were lower in groundwater samples than in surfacewater or sediment samples, with the exception of the fungicide boscalid, which was found to have its highest concentration in a shallow groundwater sample collected in Wisconsin. Thirteen pesticides, including four fungicides, were detected in suspended-sediment samples. The most frequently detected compounds were the fungicides boscalid, pyraclostrobin, and zoxamide, and the degradates p,p’-DDD and p,p’-DDE. Twenty pesticides, including six fungicides, were detected in bed-sediment samples. The most frequently detected compounds were pyraclostrobin, p,p’-DDT, p,p’-DDD, and p,p’-DDE.

Environmental impact of pesticides after sewage treatment plants removal in four Spanish Mediterranean rivers

NASA Astrophysics Data System (ADS)

Campo, Julian; Masiá, Ana; Blasco, Cristina; Picó, Yolanda; Andreu, Vicente

2013-04-01

The re-use of sewage treatment plant (STP) effluents is currently one of the most employed strategies in several countries to deal with the water shortage problem. Some pesticides are bio-accumulative and due to their toxicity they can affect non-target organisms, especially in the aquatic ecosystems, threating their ecological status. Despite these facts, and to our knowledge, there are few peer-reviewed articles that report concentrations of pesticides in Spanish STPs. This work presents the results of an extensive survey that was carried out in October of 2010 in 15 of the STPs of Ebro, Guadalquivir, Jucar and Llobregat rivers in Spain. Forty-three currently used pesticides, belonging to anilide, neonicotinoid, thiocarbamate, acaricide, juvenile hormone mimic, insect growth regulator, urea, azole, carbamate, chloroacetanilide, triazine and organophosphorus, have been monitored. Integrated samples of influent and effluent, and dehydrated, lyophilized sludge from 15 STPs located along the rivers were analyzed for pesticide residues. With these data, removal efficiencies are also calculated. Extraction of water samples was performed through Solid Phase Extraction (SPE) and sludge samples were extracted using the QuEchERS method. Pesticide determination was carried out using Liquid Chromatograph - tandem Mass Spectrometry (LC-MS/MS). Recoveries ranged from 48% to 70%, in water samples, and from 40 to 105 %, in sludge samples. The limits of quantification were 0.01-5 ng L-1 for the former, and 0.1-5.0 ng g-1 for the latter. In terms of frequency of detection, 31 analytes were detected in influent, 29 in effluent and 11 in sludge samples. Organophosphorus pesticides were the most frequently detected in all wastewater samples, but azole, urea, triazine, neonicotinoid and the insect growth regulator were also commonly found. Imazalil revealed the maximum concentration in wastewater samples from all rivers except the Guadalquivir, in which diuron presented the maximum one. Eleven pesticides including five organophosphorus, two azoles, one triazine, one chloroacetanilide, one juvenile hormone mimic and one acaricide were detected in the sludge samples. Accordingly, organophosphorus were the most frequently detected pesticides in the sludge samples, but the highest concentration was observed for imazalil. The higher concentration of this azole in the influent and their possible stronger adsorption may be the reason for their higher concentration in the sludge samples. The removal efficiency of pesticides was calculated from the analyte concentration in influent (Cin) and effluent (Cef): [(Cin-Cef)/Cin] x 100%. The removal of organophosporus ranged from -810,47 to 93,11%, meanwhile azoles and ureas were not removed in the STPs. The poor elimination of pesticides by sewage treatment plants presented in this study could be related to the treatment process used, hydraulic and solid retention times, besides the dilution and temperature of the raw sewage and the plant's configuration. These poor efficiencies are responsible of the high pesticides concentration (e.g.diuron) found in some effluents, which may endanger water quality of the ecosystem when they are re-used or directly discharged into the river. In fact, with respect to the Maximum Allowable Concentrations (MAC) stipulated by the Directive 2008/105/EC for pesticides in inland and other surface waters (Council of the European Communities, 2008), diuron exceeded these limits. Nevertheless, it is important to emphasize that, even though, the pesticides concentrations measured were relatively low (according to directives); this study analysed just some of them. A wide variety of other compounds, including other pesticides and pesticides transformation products, may contribute to the bad quality of the water ecosystems. Acknowledgements: This work has been supported by by the Spanish Ministry of Science and Innovation through the project Consolider-Ingenio 2010 (CSD2009), as well as by this Ministry and the European Regional Development Funds (ERDF) (projects CGL2011-29703-C02-00, CGL2011-29703-C02-01, CGL2011-29703-C02-02).

Monitoring of arsenic levels in some ready-to-use anti-malaria herbal products from drug sales outlets in the Madina area of Accra, Ghana.

PubMed

Affum, A O; Shiloh, D O; Adomako, D

2013-06-01

In Ghana anti-malaria herbal medicines or products are used to compliment commercial drugs in treatment and prevention of Plasmodium falciparum infections. In this study, four common aqueous based anti-malaria herbal products (coded HEB, KFE, MDM and NIB) which are used by Ghanaian population from pharmacy/herbal stores in the Madina area, Accra were blindly and randomly sampled for cadmium (Cd), arsenic (As) and Lead (Pb) analysis using Atomic Absorption Spectrophotometry technique. Arsenic concentrations were 1.087 μg/mL (108.7%), 1.027 μg/mL (102.7%), 0.330 μg/mL (33.0%) and 0.274 μg/mL (27.4%) in MDM, KFE, NIB and HEB respectively. Arsenic concentration determined in MDM and KFE were above the maximum permissible limit of 1.0 ppm determined by WHO/FAO. Cadmium concentration in each of the four products as well as lead concentration in KFE, NIB and HEB were below the detection limit of <0.002 mg/mL (Cd) and <0.005 mg/mL (Pb) respectively. The maximum permissible limits for Pb and Cd determined by WHO/FAO are 10.0 ppm and 0.3 ppm respectively. Thus, random assessment on the safety of some ready-to-use aqueous based anti-malaria herbal products on the market is necessary to prevent public health hazards associated with consuming these plant extracts. Although lead and cadmium concentration in the anti-malaria herbal products were below the maximum permissible limits, their cumulative effect on the health of an individual which consume recommended volume of not less than 1000 mL for effective malaria parasite clearance cannot be ignored. Copyright © 2013 Elsevier Ltd. All rights reserved.

Two main metabolites of gentiopicroside detected in rat plasma by LC-TOF-MS following 2,4-dinitrophenylhydrazine derivatization.

PubMed

Wang, Zhigang; Tang, Shuhan; Jin, Yan; Zhang, Yan; Hattori, Masao; Zhang, Hailong; Zhang, Ning

2015-03-25

The metabolism of gentiopicroside in vivo was studied by LC/MS following 2,4-dinitrophenylhydrazine derivatization for the first time. The ionization efficiency of the major metabolites erythrocentaurin and gentiopicral were greatly enhanced by the new analytical method developed, and they were successfully detected in rat plasma after oral administration of gentiopicroside. Methyl 4-formylbenzoate was used as the internal standard to quantify erythrocentaurin and gentiopicral in rat plasma in negative mode by UPLC-TOF-MS. It was found that erythrocentaurin reached the maximum plasma concentration of 625.2±246.3 ng/mL at about 2 h and gentiopicral reached the maximum plasma concentration of 157.6±86.6 ng/mL at about 4 h after oral administration of gentiopicroside at a dose of 200 mg/kg. The metabolic pathway of gentiopicroside to erythrocentaurin and gentiopicral was proposed. The monoterpene compound gentiopicroside was found to be metabolized to dihydroisocoumarin in vivo which may be responsible for the pharmacological effect of gentiopicroside. The results may shed light on clinical efficacy of gentiopicroside and the new analytical method developed may assist in studies for the metabolism of other natural iridoids and secoiridoids in vivo. Copyright © 2015 Elsevier B.V. All rights reserved.

Development of a lab-on-chip electrochemical biosensor for water quality analysis based on microalgal photosynthesis.

PubMed

Tsopela, A; Laborde, A; Salvagnac, L; Ventalon, V; Bedel-Pereira, E; Séguy, I; Temple-Boyer, P; Juneau, P; Izquierdo, R; Launay, J

2016-05-15

The present work was dedicated to the development of a lab-on-chip device for water toxicity analysis and more particularly herbicide detection in water. It consists in a portable system for on-site detection composed of three-electrode electrochemical microcells, integrated on a fluidic platform constructed on a glass substrate. The final goal is to yield a system that gives the possibility of conducting double, complementary detection: electrochemical and optical and therefore all materials used for the fabrication of the lab-on-chip platform were selected in order to obtain a device compatible with optical technology. The basic detection principle consisted in electrochemically monitoring disturbances in metabolic photosynthetic activities of algae induced by the presence of Diuron herbicide. Algal response, evaluated through oxygen (O2) monitoring through photosynthesis was different for each herbicide concentration in the examined sample. A concentration-dependent inhibition effect of the herbicide on photosynthesis was demonstrated. Herbicide detection was achieved through a range (blank - 1 µM Diuron herbicide solution) covering the limit of maximum acceptable concentration imposed by Canadian government (0.64 µM), using a halogen white light source for the stimulation of algal photosynthetic apparatus. Superior sensitivity results (limit of detection of around 0.1 µM) were obtained with an organic light emitting diode (OLED), having an emission spectrum adapted to algal absorption spectrum and assembled on the final system. Copyright © 2015 Elsevier B.V. All rights reserved.

Method validation and reconnaissance of pharmaceuticals, personal care products, and alkylphenols in surface waters, sediments, and mussels in an urban estuary.

PubMed

Klosterhaus, Susan L; Grace, Richard; Hamilton, M Coreen; Yee, Donald

2013-04-01

Novel methods utilizing liquid chromatography-tandem mass spectrometry and gas chromatography-mass spectrometry were validated for low-level detection of 104 pharmaceuticals and personal care products ingredients (PPCPs) and four alkylphenols (APs) in environmental samples. The methods were applied to surface water, sediment, and mussel tissue samples collected from San Francisco Bay, CA, USA, an urban estuary that receives direct discharge from over forty municipal and industrial wastewater outfalls. Among the target PPCPs, 35% were detected in at least one sample, with 31, 10, and 17 compounds detected in water, sediment, and mussels, respectively. Maximum concentrations were 92 ng/L in water (valsartan), 33 ng/g dry weight (dw) in sediments (triclocarban), and 14 ng/g wet weight (ww) in mussels (N,N-diethyl-m-toluamide). Nonylphenol was detected in water (<2-73 ng/L), sediments (22-86 ng/g dw), and mussels (<0.04-95 ng/g ww), and nonylphenol mono- and diethoxylates were detected in sediments (<1-40 ng/g dw) and mussels (<5-192 ng/g ww). The concentrations of PPCPs and APs detected in the San Francisco Bay samples were generally at least an order of magnitude below concentrations expected to elicit toxic effects in aquatic organisms. This study represents the first reconnaissance of PPCPs in mussels living in an urban estuary and provides the first field-derived bioaccumulation factors (BAFs) for select compounds in aquatic organisms. Copyright © 2013 Elsevier Ltd. All rights reserved.

Efficient ensemble system based on the copper binding motif for highly sensitive and selective detection of cyanide ions in 100% aqueous solutions by fluorescent and colorimetric changes.

PubMed

Jung, Kwan Ho; Lee, Keun-Hyeung

2015-09-15

A peptide-based ensemble for the detection of cyanide ions in 100% aqueous solutions was designed on the basis of the copper binding motif. 7-Nitro-2,1,3-benzoxadiazole-labeled tripeptide (NBD-SSH, NBD-SerSerHis) formed the ensemble with Cu(2+), leading to a change in the color of the solution from yellow to orange and a complete decrease of fluorescence emission. The ensemble (NBD-SSH-Cu(2+)) sensitively and selectively detected a low concentration of cyanide ions in 100% aqueous solutions by a colorimetric change as well as a fluorescent change. The addition of cyanide ions instantly removed Cu(2+) from the ensemble (NBD-SSH-Cu(2+)) in 100% aqueous solutions, resulting in a color change of the solution from orange to yellow and a "turn-on" fluorescent response. The detection limits for cyanide ions were lower than the maximum allowable level of cyanide ions in drinking water set by the World Health Organization. The peptide-based ensemble system is expected to be a potential and practical way for the detection of submicromolar concentrations of cyanide ions in 100% aqueous solutions.

40 CFR Table 1 to Subpart A of... - Maximum Concentration of Constituents for Groundwater Protection

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Maximum Concentration of Constituents for Groundwater Protection 1 Table 1 to Subpart A of Part 192 Protection of Environment ENVIRONMENTAL... Concentration of Constituents for Groundwater Protection Constituent concentration 1 Maximum Arsenic 0.05 Barium...

40 CFR Table 1 to Subpart A of... - Maximum Concentration of Constituents for Groundwater Protection

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 26 2013-07-01 2013-07-01 false Maximum Concentration of Constituents for Groundwater Protection 1 Table 1 to Subpart A of Part 192 Protection of Environment ENVIRONMENTAL... Concentration of Constituents for Groundwater Protection Constituent concentration 1 Maximum Arsenic 0.05 Barium...

40 CFR Table 1 to Subpart A of... - Maximum Concentration of Constituents for Groundwater Protection

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Maximum Concentration of Constituents for Groundwater Protection 1 Table 1 to Subpart A of Part 192 Protection of Environment ENVIRONMENTAL... Concentration of Constituents for Groundwater Protection Constituent concentration 1 Maximum Arsenic 0.05 Barium...

40 CFR Table 1 to Subpart A of... - Maximum Concentration of Constituents for Groundwater Protection

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Maximum Concentration of Constituents for Groundwater Protection 1 Table 1 to Subpart A of Part 192 Protection of Environment ENVIRONMENTAL... Concentration of Constituents for Groundwater Protection Constituent concentration 1 Maximum Arsenic 0.05 Barium...

Concentrations of organochlorine pesticides, polybrominated diphenyl ethers and perfluorinated compounds in the atmosphere of North Greenland.

PubMed

Bossi, Rossana; Vorkamp, Katrin; Skov, Henrik

2016-10-01

Atmospheric concentrations of organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs) and neutral per- and polyfluoroalkyl substances (PFAS) have been measured at Villum Research Station, Station Nord (North Greenland) in the period 2008-2013. Atmospheric concentrations of OCPs at the same site have been previously reported for the years 2008-2010. The detection frequency and the average concentrations of OCPs have not significantly changed since the previous study. PBDE congeners (∑13PBDEs) were measured for the first time in North Greenland at concentrations similar to those observed for other remote sites, confirming that these compounds are ubiquitous in the Northern Hemisphere. The ∑13PBDEs concentration ranged from not detected (n.d.) to 6.26 pg m(-3). The BDE congeners found in more than 30% of the samples were BDE-17, BDE-28, BDE-47, BDE-71, BDE-99 and BDE-100. Also for neutral PFAS we present for the first time a multiyear series of measurements for North Greenland. The average sum of the seven measured neutral PFAS (∑7PFAS) ranged from 1.82 to 32.1 pg m(-3). The most abundant compound was 8:2 FTOH (44% of ∑7PFAS), followed by 6:2 FTOH and 10:2 FTOH. Perfluoroalkyl sulfonamides (FOSA) and perfluoroalkyl sulfonamidoethanols (FOSE) were also detected but at much lower concentrations than FTOHs. Temporal trends were investigated for all measured compounds but no significant trend in concentration was observed. Monthly average concentrations for the six years were calculated for each compound and the seasonal variation was investigated. Some OCPs and FTOHs showed seasonal variations, and in most cases a maximum was found during summer. Copyright © 2016 Elsevier Ltd. All rights reserved.

Arsenic and trace elements in soil, water, grapevine and onion in Jáchal, Argentina.

PubMed

Funes Pinter, Iván; Salomon, M Victoria; Gil, Raúl; Mastrantonio, Leandro; Bottini, Rubén; Piccoli, Patricia

2018-02-15

Contamination by trace elements (TE) is an increasing concern worldwide. In some areas, crop production could be limited by the presence of metals and metalloids, so it is important to determine their concentrations and mobility. The region of Jáchal, province of San Juan, Argentina, has good growing conditions for onion and grapevine production, but their quality and yield are affected by high TE concentration in soils and water. Soils, water, grapevine and onion were sampled and TE content determined. In soils elevated As, B, Cr, Hg, and Tl concentrations were detected (506±46, 149±3, 2714±217, 16±7, and 12±3μgg -1 , respectively, for maximum values measured), and physicochemical properties of the soil promotes these elements mobility. Water samples had high As, B, Cr, and Fe concentrations (1438±400, 10,871±471, 11,516±2363, and 3071±257μgL -1 , respectively, for maximum values measured) while in onion bulbs and grapevine berries, As, Cr, Cu, and Fe (92±7 and 171±20, 1412±18 and 2965±32, 17±3 and 126±88, and 418±204 and 377±213μgg -1 , respectively, for maximum values measured) exceeded the limits for food consumption established by Argentinian law. Correlation analyses indicated that: i) there is a common source of TE in this area, ii) each elements concentration in plants is associated with different soil variables and different soils depths, and iii) the lack of correlation between soil and water indicates that concentration in water is not constant over the time and/or there exists a differential accumulation of elements in soils depending on their own properties. Data obtained demonstrate very high concentration of TE in soil, grapevines, and onion plants in Jáchal region, and different remediation techniques are necessary to stabilize and minimize the bioavailability of these elements. Copyright © 2017 Elsevier B.V. All rights reserved.

Application of a CO2 dial system for infrared detection of forest fire and reduction of false alarm

NASA Astrophysics Data System (ADS)

Bellecci, C.; Francucci, M.; Gaudio, P.; Gelfusa, M.; Martellucci, S.; Richetta, M.; Lo Feudo, T.

2007-04-01

Forest fires can be the cause of serious environmental and economic damages. For this reason considerable effort has been directed toward forest protection and fire fighting. The means traditionally used for early fire detection mainly consist in human observers dispersed over forest regions. A significant improvement in early warning capabilities could be obtained by using automatic detection apparatus. In order to early detect small forest fires and minimize false alarms, the use of a lidar system and dial technique will be considered. A first evaluation of the lowest detectable concentration will be estimated by numerical simulation. The theoretical model will also be used to get the capability of the dial system to control wooded areas. Fixing the burning rate for several fuels, the maximum range of detection will be evaluated. Finally results of simulations will be reported.

Survey of carbamate and organophosphorous pesticide export from a south Florida (U.S.A.) agricultural watershed: implications of sampling frequency on ecological risk estimation.

PubMed

Wilsont, P Chris; Foos, Jane Ferguson

2006-11-01

The objectives of the present study were to characterize the presence of selected carbamate and organophosphorous pesticides in Ten Mile Creek (Fort Pierce, FL, U.S.A.) and to evaluate the implications of sampling frequency on ecological risk estimates. Ten Mile Creek originates in a predominately agricultural watershed that is drained by an extensive network of cross-linked canals. Water samples were collected daily or every other day and were analyzed for azinphos-methyl, chlorpyrifos, diazinon, dimethoate, ethion, fenamiphos, malathion, methidathion, carbaryl, carbofuran, 3-hydroxycarbofuran, methiocarb, methomyl, oxamyl, and propoxur. A total of 457 samples were analyzed for the carbamate suite, and a total of 332 samples were analyzed for the organophosphorous suite. Carbaryl was detected in eight samples; half of these detections occurred on four consecutive days (October 26-29, 2001) at concentrations ranging from 0.33 to 0.95 microg/L. Methomyl was detected in samples collected on five consecutive days (March 30-April 3, 2002) at concentrations ranging from 1.0 to 2.2 microg/L. Oxamyl was detected in four samples, three of which occurred on three consecutive days (February 17-19, 2002) at concentrations ranging from 6.2 to 6.8 microg/L. The carbamates propoxur, 3-hydroxycarbofuran, carbofuran, and methiocarb were not detected. Diazinon and ethion were the only organophosphorous pesticides detected. Diazinon was detected at 0.9 and 0.7 microg/L on January 5, 2002, and on January 6, 2002, respectively. Ethion was detected in 18 consecutive samples (August 3-20, 2001). The mean, maximum, minimum, and median detected concentrations were 0.38, 0.61, 0.30, and 0.33 microg/L, respectively. Results indicate that frequent sampling is necessary to characterize the presence of these pesticides in this intensively drained watershed. This conclusion also may apply to similar canalized watersheds.

Groundwater quality in the Chemung River Basin, New York, 2008

USGS Publications Warehouse

Risen, Amy J.; Reddy, James E.

2011-01-01

The second groundwater quality study of the Chemung River Basin in south-central New York was conducted as part of the U.S. Geological Survey 305(b) water-quality-monitoring program. Water samples were collected from five production wells and five private residential wells from October through December 2008. The samples were analyzed to characterize the chemical quality of the groundwater. Five of the wells are screened in sand and gravel aquifers, and five are finished in bedrock aquifers. Two of these wells were also sampled for the first Chemung River Basin study of 2003. Samples were analyzed for 6 physical properties and 217 constituents, including nutrients, major inorganic ions, trace elements, radionuclides, pesticides, volatile organic compounds, phenolic compounds, organic carbon, and four types of bacterial analyses. Results of the water-quality analyses for individual wells are presented in tables, and summary statistics for specific constituents are presented by aquifer type. The results are compared with Federal and New York State drinking-water standards, which typically are identical. Water quality in the study area is generally good, but concentrations of some constituents equaled or exceeded current or proposed Federal or New York State drinking-water standards; these were: sodium (one sample), total dissolved solids (one sample), aluminum (one sample), iron (one sample), manganese (four samples), radon-222 (eight samples), trichloroethene (one sample), and bacteria (four samples). The pH of all samples was typically neutral or slightly basic (median 7.5); the median water temperature was 11.0 degrees Celsius (?C). The ions with the highest median concentrations were bicarbonate (median 202 milligrams per liter [mg/L]) and calcium (median 59.0 mg/L). Groundwater in the study area is moderately hard to very hard, but more samples were hard or very hard (121 mg/L as calcium carbonate (CaCO3) or greater) than were moderately hard (61-120 mg/L as CaCO3); the median hardness was 205 mg/L as CaCO3. The maximum concentration of nitrate plus nitrite was 3.67 mg/L as nitrogen, which did not exceed established drinking-water standards for nitrate plus nitrite (10 mg/L as nitrogen). The trace elements with the highest median concentrations were strontium (median 196.5 micrograms per liter [(u or mu)g/L]), barium (median 186 (u or mu)g/L), and iron (median 72.5 (u or mu)g/L in unfiltered water). Five pesticides and pesticide degradates were detected among four samples at concentrations of 0.11 (u or mu)g/L or less; they included herbicides and herbicide degradates. Six volatile organic compounds (VOCs) were detected among four samples; these included four solvents, methyl tert-butyl ether, and one trihalomethane. Trichloroethene, a solvent, was detected in one production well at 5.5 (u or mu)g/L; the Federal and New York State Maximum Contaminant Level (MCL) (5 (u or mu)g/L) was exceeded. The highest radon-222 activities were in samples from bedrock wells [maximum 1,740 picocuries per liter (pCi/L)]; eight of the wells sampled exceeded a proposed U.S. Environmental Protection Agency (USEPA) drinking-water standard of 300 pCi/L. Any detection of coliform bacteria indicates a potential violation of New York State health regulations; total coliform bacteria were detected in four samples, and fecal coliform bacteria were detected in one sample.μμμ

Occurrence, distribution, and volume of metals-contaminated sediment of selected streams draining the Tri-State Mining District, Missouri, Oklahoma, and Kansas, 2011–12

USGS Publications Warehouse

Smith, D. Charlie

2016-12-14

Lead and zinc were mined in the Tri-State Mining District (TSMD) of southwest Missouri, northeast Oklahoma, and southeast Kansas for more than 100 years. The effects of mining on the landscape are still evident, nearly 50 years after the last mine ceased operation. The legacies of mining are the mine waste and discharge of groundwater from underground mines. The mine-waste piles and underground mines are continuous sources of trace metals (primarily lead, zinc, and cadmium) to the streams that drain the TSMD. Many previous studies characterized the horizontal extent of mine-waste contamination in streams but little information exists on the depth of mine-waste contamination in these streams. Characterizing the vertical extent of contamination is difficult because of the large amount of coarse-grained material, ranging from coarse gravel to boulders, within channel sediment. The U.S. Geological Survey, in cooperation with U.S. Fish and Wildlife service, collected channel-sediment samples at depth for subsequent analyses that would allow attainment of the following goals: (1) determination of the relation between concentration and depth for lead, zinc and cadmium in channel sediments and flood-plain sediments, and (2) determination of the volume of gravel-bar sediment from the surface to the maximum depth with concentrations of these metals that exceeded sediment-quality guidelines. For the purpose of this report, volume of gravel-bar sediment is considered to be distributed in two forms, gravel bars and the wetted channel, and this study focused on gravel bars. Concentrations of lead, zinc, and cadmium in samples were compared to the consensus probable effects concentration (CPEC) and Tri-State Mining District specific probable effects concentration (TPEC) sediment-quality guidelines.During the study, more than 700 sediment samples were collected from borings at multiple sites, including gravel bars and flood plains, along Center Creek, Turkey Creek, Shoal Creek, Tar Creek, and Spring River in order to characterize the vertical extent of mine waste in select streams in the TSMD. The largest concentrations of lead, zinc, and cadmium in gravel bar-sediment samples generally were detected in Turkey Creek and Tar Creek and the smallest concentrations were detected in Shoal Creek followed by the Spring River. Gravel bar-sediment samples from Turkey Creek exceeded the CPEC for cadmium (minimum of 70 percent of samples), lead (94 percent), and zinc (99 percent) at a slightly higher frequency than similar samples from Tar Creek (69 percent, 88 percent, and 96 percent, respectively). Gravel bar-sediment samples from Turkey Creek also contained the largest concentrations of cadmium (174 milligrams per kilogram [mg/kg]) and lead (7,520 mg/kg) detected; however, the largest zinc concentration (46,600 mg/kg) was detected in a gravel bar-sediment sample from Tar Creek. In contrast, none of the 65 gravel bar-sediment samples from Shoal Creek contained cadmium above the x-ray fluorescence reporting level of 12 mg/kg, and lead and zinc exceeded the CPEC in only 12 percent and 74 percent of samples, respectively. In most cases, concentrations of lead and zinc above the CPEC or TPEC were present at the maximum depth of boring, which indicated that nearly the entire thickness of sediment in the stream has been contaminated by mine wastes. Approximately 284,000 cubic yards of channel sediment from land surface to the maximum depth that exceeded the CPEC and approximately 236,000 cubic yards of channel sediment from land surface to the maximum depth that exceeded the TPEC were estimated along 37.6 of the 55.1 miles of Center Creek, Turkey Creek, Shoal Creek, and Tar Creek examined in this study. Mine-waste contamination reported along additional reaches of these streams is beyond the scope of this study. Flood-plain cores collected in the TSMD generally only had exceedances of the CPEC and TPEC for lead and zinc in the top 1 or 2 feet of soil with a few exceptions, such as cores in low areas near the stream or cores in areas disturbed by past mining.

Geochemistry of soils and shallow ground water, with emphasis on arsenic and selenium, in part of the Garrison Diversion Unit, North Dakota, 1985-87

USGS Publications Warehouse

Goolsby, D.A.; Severson, R.C.; Wilson, S.A.; Webber, Kurt

1989-01-01

The Garrison Diversion Unit is being constructed to transfer water from the Missouri River (Lake Sakakawea) to areas in east-central and southeastern North Dakota for expanded irrigation of agricultural lands. During initial investigations of irrigation return flows in 1969-76, the potential effects of toxic elements were considered, and the U.S. Bureau of Reclamation concluded these elements would have no adverse effects on streams receiving return flows. After the development of problems associated with selenium in irrigation return flows in the western San Joaquin Valley, Calif., in 1985, the U.S. Bureau of Reclamation initiated additional studies, including an investigation conducted in cooperation with the U.S. Geological Survey, to assist in collecting and evaluating trace-element data. Also, in 1986, with the passage of the Garrison Diversion Unit Reformulation Act, Congress mandated that soil surveys be conducted to determine if there are "*** soil characteristics which might result in toxic or hazardous irrigation return flows."In order to address this issue, an investigation was conducted during 1995-87 by the U.S. Geological Survey in cooperation with the U.S. Bureau of Reclamation to determine the occurrence and distribution of arsenic, selenium, and other trace elements in the soils of six potential irrigation areas along the Garrison Diversion Unit route and in the James River basin. A total of 165 soil samples were collected and analyzed for total concentrations of as many as 42 elements, including arsenic and selenium. In addition, 81 of the samples were analyzed for water-extractable concentrations of 14 elements, including arsenic and selenium, to aid in determining the extent to which they might be mobilized by the irrigation water. In a detailed phase of the investigation, 376 water samples were collected in one of the six potential irrigation areas, the west Oakes irrigation area. Most of these samples were analyzed for arsenic, selenium, and as many as 28 other elements.Results of the investigation indicate that soils in the potential irrigation areas contain small concentrations of arsenic, selenium, and other trace elements. The geometric mean concentrations of total arsenic and selenium were 4.15 and 0.13 milligrams per kilogram, respectively, which are considerably smaller than those measured in the western San Joaquin Valley, Calif., and soils from other areas in the western United States. Water-extractable concentrations of arsenic and selenium, determined on 1:5 soil to water extractions, generally were less than 10 percent of the total concentrations. The geometric mean water-extractable concentrations for both elements were 0.02 milligram per kilogram or less.The median and maximum concentrations of all constituents and properties indicative of irrigation drainage were tens to hundreds of times smaller in the Oakes test area drains than in western San Joaquin Valley drains. The maximum arsenic concentration in ground-water samples was 44 micrograms per liter, and the median concentration was 4 micrograms per liter. The maximum concentration in drain samples was 11 micrograms per liter, and the median concentration was 3 micrograms per liter.Only 22 percent of the water samples collected from wells in the Oakes test area contained detectable concentrations (1 microgram per liter or more) of selenium. However, selenium was detected in 63 percent of the samples collected from sites on drains. The greater incidence of detection of selenium in the drain samples is interpreted as an effect of the more oxidizing environment of the drains, which are about 8 feet below land surface near the top of the water table. The median selenium concentration in the drain samples, however, was only 1 microgram per liter, and the maximum concentration in 63 drain samples was 4 micrograms per liter. For comparison, the median selenium concentrations reported for drains in the western San Joaquin Valley, Calif., ranged from 84 to 320 micrograms per liter. Mater from two observation wells had the largest selenium concentrations (8 and 9 micrograms per liter) measured during the investigation. These were the only two samples that exceeded any of the water-quality regulations, standards, or criteria for selenium. Mercury and boron were the only other trace elements that exceeded standards and criteria. The median concentration of mercury was less than 0.1 microgram per liter, and the maximum concentration was 0.8 microgram per liter. The chronic freshwater-aquatic-life criterion for mercury (0.012 microgram per liter) is about 10 times less than the laboratory detection limit and is derived from bioconcentration factors based on methylmercury. Two boron samples exceeded the irrigation criteria of 750 micrograms per liter. Comparisons with criteria and standards indicate that the concentrations of trace elements determined in samples from wells and drains in the Oakes test area during this investigation should not adversely affect human and aquatic life or irrigated crops. The data collected indicate that the soils and ground water in the Garrison Diversion Unit contain small concentrations of trace elements, including arsenic and selenium. Based on a detailed study of soils and ground water in the west Oakes irrigation area, however, there is no evidence that expanded irrigation will mobilize these elements in concentrations large enough to adversely affect aquatic life in the James River ecosystem, based on current regulations, standards, and criteria. Data are not currently available to make definitive statements about selenium concentrations in ground water in Garrison Diversion Unit irrigation areas other than the west Oakes Irrigation area. Data available on total and water-extractable selenium concentrations in soils t however, indicate that concentrations in ground water would be similar to those determined in the west Oakes irrigation area. Plans have been developed to sample ground water in the additional areas.

Development of a multianalyte method based on micro-matrix-solid-phase dispersion for the analysis of fragrance allergens and preservatives in personal care products.

PubMed

Celeiro, Maria; Guerra, Eugenia; Lamas, J Pablo; Lores, Marta; Garcia-Jares, Carmen; Llompart, Maria

2014-05-30

An effective, simple and low cost sample preparation method based on matrix solid-phase dispersion (MSPD) followed by gas chromatography-mass spectrometry (GC-MS) or gas chromatography-triple quadrupole-mass spectrometry (GC-MS/MS) has been developed for the rapid simultaneous determination of 38 cosmetic ingredients, 25 fragrance allergens and 13 preservatives. All target substances are frequently used in cosmetics and personal care products and they are subjected to use restrictions or labeling requirements according to the EU Cosmetic Directive. The extraction procedure was optimized on real non-spiked rinse-off and leave-on cosmetic products by means of experimental designs. The final miniaturized process required the use of only 0.1g of sample and 1 mL of organic solvent, obtaining a final extract ready for analysis. The micro-MSPD method was validated showing satisfactory performance by GC-MS and GC-MS/MS analysis. The use of GC coupled to triple quadrupole mass detection allowed to reach very low detection limits (low ng g(-1)) improving, at the same time, method selectivity. In an attempt to improve the chromatographic analysis of preservatives, the inclusion of a derivatization step was also assessed. The proposed method was applied to a broad range of cosmetics and personal care products (shampoos, body milk, moisturizing milk, toothpaste, hand creams, gloss lipstick, sunblock, deodorants and liquid soaps among others), demonstrating the extended use of these substances. The concentration levels were ranging from the sub parts per million to the parts per mill. The number of target fragrance allergens per samples was quite high (up to 16). Several fragrances (linalool, farnesol, hexylcinnamal, and benzyl benzoate) have been detected at levels >0.1% (1,000 μg g(-1)). As regards preservatives, phenoxyethanol was the most frequently found additive reaching quite high concentration (>1,500 μg g(-1)) in five cosmetic products. BHT was detected in eight samples, in two of them (a baby care product and a lipstick) at high concentrations (>1,000 μg g(-1)). Methyl paraben was also found at high levels (>1,700 μg g(-1)) in three leave-on samples. Finally, triclosan was found at the maximum concentration limit (0.3%) laid down by the European regulation in two deodorant samples, and the total paraben concentration was close to the maximum concentration permitted (0.8%) in one leave-on sample (body milk). Copyright © 2014 Elsevier B.V. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

LaFreniere, L. M.; Environmental Science Division

The investigation reported here was conducted by the Commodity Credit Corporation of the U.S. Department of Agriculture (CCC/USDA) in 2006. The investigation addressed carbon tetrachloride contamination on the former CCC/USDA grain storage facility at Ramona, Kansas. The results clearly demonstrate that only minimal contamination is associated with the past use of carbon tetrachloride on the former CCC/USDA property. No soil contamination was detected at concentrations above Kansas Department of Health and Environment (KDHE) risk-based screening level (RBSL) Tier 2 standard of 200 {micro}g/kg for the soil-to-groundwater protection pathway. Carbon tetrachloride concentrations in groundwater above the RBSL and maximum contaminant levelmore » (MCL) value of 5.0 {micro}g/L were detected in only two samples, collected at adjacent locations on the southeast part of the property. The relatively low concentrations detected and the limited areal extent of the contamination demonstrate that no imminent threat exists on the former CCC/USDA property to warrant remediation. The soil and groundwater contamination detected on the former CCC/USDA property is clearly separate from contamination detected at off-site locations. The carbon tetrachloride and chloroform contamination in groundwater (at concentrations above the RBSL and MCL value) associated with past activities on the former CCC/USDA property is contained within the property boundaries. Data collected independently by the KDHE in 2006 validate these findings and, furthermore, provide additional evidence that the sources identified on the Co-op property (west of the former CCC/USDA property) are separate from the comparatively minor results of past activities on the former CCC/USDA property. The KDHE concluded in its 2006 report that the sources are separate and that the Co-op is the principally responsible party for the carbon tetrachloride contamination detected during its 2006 investigation.« less

Markers of anthropogenic contamination: A validated method for quantification of pharmaceuticals, illicit drug metabolites, perfluorinated compounds, and plasticisers in sewage treatment effluent and rain runoff.

PubMed

Wilkinson, John L; Swinden, Julian; Hooda, Peter S; Barker, James; Barton, Stephen

2016-09-01

An effective, specific and accurate method is presented for the quantification of 13 markers of anthropogenic contaminants in water using solid phase extraction (SPE) followed by high performance liquid chromatography (HPLC) tandem mass spectrometry (MS/MS). Validation was conducted according to the International Conference on Harmonisation (ICH) guidelines. Method recoveries ranged from 77 to 114% and limits of quantification between 0.75 and 4.91 ng/L. A study was undertaken to quantify the concentrations and loadings of the selected contaminants in 6 sewage treatment works (STW) effluent discharges as well as concentrations in 5 rain-driven street runoffs and field drainages. Detection frequencies in STW effluent ranged from 25% (ethinylestradiol) to 100% (benzoylecgonine, bisphenol-A (BPA), bisphenol-S (BPS) and diclofenac). Average concentrations of detected compounds in STW effluents ranged from 3.62 ng/L (ethinylestradiol) to 210 ng/L (BPA). Levels of perfluorinated compounds (PFCs) perfluorooctanoic acid (PFOA) and perfluorononanoic acid (PFNA) as well as the plasticiser BPA were found in street runoff at maximum levels of 1160 ng/L, 647 ng/L and 2405 ng/L respectively (8.52, 3.09 and 2.7 times more concentrated than maximum levels in STW effluents respectively). Rain-driven street runoff may have an effect on levels of PFCs and plasticisers in receiving rivers and should be further investigated. Together, this method with the 13 selected contaminants enables the quantification of various markers of anthropogenic pollutants: inter alia pharmaceuticals, illicit drugs and their metabolites from humans and improper disposal of drugs, while the plasticisers and perfluorinated compounds may also indicate contamination from industrial and transport activity (street runoff). Copyright © 2016 Elsevier Ltd. All rights reserved.

Pharmaceuticals, perfluorosurfactants, and other organic wastewater compounds in public drinking water wells in a shallow sand and gravel aquifer.

PubMed

Schaider, Laurel A; Rudel, Ruthann A; Ackerman, Janet M; Dunagan, Sarah C; Brody, Julia Green

2014-01-15

Approximately 40% of U.S. residents rely on groundwater as a source of drinking water. Groundwater, especially unconfined sand and gravel aquifers, is vulnerable to contamination from septic systems and infiltration of wastewater treatment plant effluent. In this study, we characterized concentrations of pharmaceuticals, perfluorosurfactants, and other organic wastewater compounds (OWCs) in the unconfined sand and gravel aquifer of Cape Cod, Massachusetts, USA, where septic systems are prevalent. Raw water samples from 20 public drinking water supply wells on Cape Cod were tested for 92 OWCs, as well as surrogates of wastewater impact. Fifteen of 20 wells contained at least one OWC; the two most frequently-detected chemicals were sulfamethoxazole (antibiotic) and perfluorooctane sulfonate (perfluorosurfactant). Maximum concentrations of sulfamethoxazole (113 ng/L) and the anticonvulsant phenytoin (66 ng/L) matched or exceeded maximum reported concentrations in other U.S. public drinking water sources. The sum of pharmaceutical concentrations and the number of detected chemicals were both significantly correlated with nitrate, boron, and extent of unsewered residential and commercial development within 500 m, indicating that wastewater surrogates can be useful for identifying wells most likely to contain OWCs. Septic systems appear to be the primary source of OWCs in Cape Cod groundwater, although wastewater treatment plants and other sources were potential contributors to several wells. These results show that drinking water supplies in unconfined aquifers where septic systems are prevalent may be among the most vulnerable to OWCs. The presence of mixtures of OWCs in drinking water raises human health concerns; a full evaluation of potential risks is limited by a lack of health-based guidelines and toxicity assessments. © 2013. Published by Elsevier B.V. All rights reserved.

PAHs in polystyrene food contact materials: An unintended consequence.

PubMed

Li, Si-Qi; Ni, Hong-Gang; Zeng, Hui

2017-12-31

Eight low-ring PAHs were detected in 21 polystyrene (PS) food contact materials (FCMs) samples while high-ring PAHs (>4 rings) were not found. This is because the reaction pathway for formation of high-ring PAHs consists of more steps than it does for low-high PAHs. The concentrations of Σ 8 PAH were from 18.9±5.16ng/g for product colorless fruit fork to 476±52.0ng/g for foam instant noodle container. These data were far beyond levels of PAHs in other plastics. Of the eight PAHs detected, Phe had the highest average concentration, followed by Nap. These two PAHs collectively accounted for over 80% of the Σ 8 PAH concentrations in all PS FCMs. Levels of Σ 8 PAH in expanded PS FCMs were higher than those in extruded ones due to utilization of foaming agent. The concentrations of Σ 8 PAH were lower in colorless PS FCMs than in colored ones. Auxochromes and chromophores contributed to the change of short-chain hydrocarbons to aromatic hydrocarbon. Simulated migration values of PAHs from PS FCMs to food varied widely. The migration value of Σ 8 PAH with maximum probability was below 10ng/g, which the maximum tolerated migration level for substance according to the European Union standards. However, higher migration values were possible and the potential health risk should still be concerned because the simulated migration displayed a log-normal distribution. Furthermore, water was used as food simulant would always lead to an underestimate of PAHs migration to real daily food, and then lead to an underestimate of risk. Copyright © 2017 Elsevier B.V. All rights reserved.

Using a Hazard Quotient to Evaluate Pesticide Residues Detected in Pollen Trapped from Honey Bees (Apis mellifera) in Connecticut

PubMed Central

Stoner, Kimberly A.; Eitzer, Brian D.

2013-01-01

Analysis of pollen trapped from honey bees as they return to their hives provides a method of monitoring fluctuations in one route of pesticide exposure over location and time. We collected pollen from apiaries in five locations in Connecticut, including urban, rural, and mixed agricultural sites, for periods from two to five years. Pollen was analyzed for pesticide residues using a standard extraction method widely used for pesticides (QuEChERS) and liquid chromatography/mass spectrometric analysis. Sixty pesticides or metabolites were detected. Because the dose lethal to 50% of adult worker honey bees (LD50) is the only toxicity parameter available for a wide range of pesticides, and among our pesticides there were contact LD50 values ranging from 0.006 to >1000 μg per bee (range 166,000X), and even among insecticides LD50 values ranged from 0.006 to 59.8 μg/bee (10,000X); therefore we propose that in studies of honey bee exposure to pesticides that concentrations be reported as Hazard Quotients as well as in standard concentrations such as parts per billion. We used both contact and oral LD50 values to calculate Pollen Hazard Quotients (PHQ = concentration in ppb ÷ LD50 as μg/bee) when both were available. In this study, pesticide Pollen Hazard Quotients ranged from over 75,000 to 0.01. The pesticides with the greatest Pollen Hazard Quotients at the maximum concentrations found in our study were (in descending order): phosmet, Imidacloprid, indoxacarb, chlorpyrifos, fipronil, thiamethoxam, azinphos-methyl, and fenthion, all with at least one Pollen Hazard Quotient (using contact or oral LD50) over 500. At the maximum rate of pollen consumption by nurse bees, a Pollen Hazard Quotient of 500 would be approximately equivalent to consuming 0.5% of the LD50 per day. We also present an example of a Nectar Hazard Quotient and the percentage of LD50 per day at the maximum nectar consumption rate. PMID:24143241

Concentration, size distribution and dry deposition of amines in atmospheric particles of urban Guangzhou, China

NASA Astrophysics Data System (ADS)

Liu, Fengxian; Bi, Xinhui; Zhang, Guohua; Peng, Long; Lian, Xiufeng; Lu, Huiying; Fu, Yuzhen; Wang, Xinming; Peng, Ping'an; Sheng, Guoying

2017-12-01

Size-segregated PM10 samples were collected in Guangzhou, China during autumn of 2014. Nine amines, including seven aliphatic amines and two heterocyclic amines, were detected using a gas chromatography-mass spectrometer after derivatization by benzenesulfonyl chloride. The total concentration of the nine amines (Ʃamines) was 79.6-140.9 ng m-3 in PM10. The most abundant species was methylamine (MA), which had a concentration of 29.2-70.1 ng m-3. MA, dimethylamine (DMA), diethylamine (DEA) and dibutylamine (DBA) were the predominant amines in the samples and accounted for approximately 80% of Ʃamines in each size segment. Two heterocyclic amines, pyrrolidine (PYR) and morpholine (MOR), were detected in all samples and had average concentrations of 1.14 ± 0.37 and 1.89 ± 0.64 ng m-3, respectively, in particles with aerodynamic diameters < 3 μm. More than 80% of Ʃamines were found in particles with diameters <1.5 μm, indicating that amines are mainly enriched in fine particles. All amines exhibited a bimodal distribution with a fine mode at 0.49-1.5 μm and a coarse mode at 7.2-10 μm. The maximum contributions of amines to particles (0.21%) and amines-N to water-soluble organic nitrogen (WSON) (3.1%) were found at the sizes < 0.49 μm. The maximum contribution of amines-C to water-soluble organic carbon (WSOC) was 1.6% over the size range of 0.95-1.5 μm. The molar ratio of Ʃamines to ammonium ranged from 0.0068 to 0.0107 in particles with diameters <1.5 μm, and the maximum ratio occurred in the smallest particles (diameter< 0.49 μm). The average dry deposition flux and velocity of Ʃamines in PM10 were 7.9 ± 1.6 μg m-2 d-1 and 0.084 ± 0.0021 cm s-1, respectively. The results of this study provide essential information on the contribution of amines to secondary organic aerosols and dry removal mechanisms in urban areas.

Using a hazard quotient to evaluate pesticide residues detected in pollen trapped from honey bees (Apis mellifera) in Connecticut.

PubMed

Stoner, Kimberly A; Eitzer, Brian D

2013-01-01

Analysis of pollen trapped from honey bees as they return to their hives provides a method of monitoring fluctuations in one route of pesticide exposure over location and time. We collected pollen from apiaries in five locations in Connecticut, including urban, rural, and mixed agricultural sites, for periods from two to five years. Pollen was analyzed for pesticide residues using a standard extraction method widely used for pesticides (QuEChERS) and liquid chromatography/mass spectrometric analysis. Sixty pesticides or metabolites were detected. Because the dose lethal to 50% of adult worker honey bees (LD50) is the only toxicity parameter available for a wide range of pesticides, and among our pesticides there were contact LD50 values ranging from 0.006 to >1000 μg per bee (range 166,000X), and even among insecticides LD50 values ranged from 0.006 to 59.8 μg/bee (10,000X); therefore we propose that in studies of honey bee exposure to pesticides that concentrations be reported as Hazard Quotients as well as in standard concentrations such as parts per billion. We used both contact and oral LD50 values to calculate Pollen Hazard Quotients (PHQ = concentration in ppb ÷ LD50 as μg/bee) when both were available. In this study, pesticide Pollen Hazard Quotients ranged from over 75,000 to 0.01. The pesticides with the greatest Pollen Hazard Quotients at the maximum concentrations found in our study were (in descending order): phosmet, Imidacloprid, indoxacarb, chlorpyrifos, fipronil, thiamethoxam, azinphos-methyl, and fenthion, all with at least one Pollen Hazard Quotient (using contact or oral LD50) over 500. At the maximum rate of pollen consumption by nurse bees, a Pollen Hazard Quotient of 500 would be approximately equivalent to consuming 0.5% of the LD50 per day. We also present an example of a Nectar Hazard Quotient and the percentage of LD50 per day at the maximum nectar consumption rate.

Modelling Short-Term Maximum Individual Exposure from Airborne Hazardous Releases in Urban Environments. Part ΙI: Validation of a Deterministic Model with Wind Tunnel Experimental Data.

PubMed

Efthimiou, George C; Bartzis, John G; Berbekar, Eva; Hertwig, Denise; Harms, Frank; Leitl, Bernd

2015-06-26

The capability to predict short-term maximum individual exposure is very important for several applications including, for example, deliberate/accidental release of hazardous substances, odour fluctuations or material flammability level exceedance. Recently, authors have proposed a simple approach relating maximum individual exposure to parameters such as the fluctuation intensity and the concentration integral time scale. In the first part of this study (Part I), the methodology was validated against field measurements, which are governed by the natural variability of atmospheric boundary conditions. In Part II of this study, an in-depth validation of the approach is performed using reference data recorded under truly stationary and well documented flow conditions. For this reason, a boundary-layer wind-tunnel experiment was used. The experimental dataset includes 196 time-resolved concentration measurements which detect the dispersion from a continuous point source within an urban model of semi-idealized complexity. The data analysis allowed the improvement of an important model parameter. The model performed very well in predicting the maximum individual exposure, presenting a factor of two of observations equal to 95%. For large time intervals, an exponential correction term has been introduced in the model based on the experimental observations. The new model is capable of predicting all time intervals giving an overall factor of two of observations equal to 100%.

Seasonal and spatial variability of nutrients and pesticides in streams of the Willamette Basin, Oregon, 1993-95

USGS Publications Warehouse

Rinella, F.A.; Janet, M.L.

1998-01-01

From April 1993 to September 1995, the U.S. Geological Survey conducted a study of the occurrence and distribution of nutrients and pesticides in surface water of the Willamette and Sandy River Basins, Oregon, as part of the U.S. Geological Survey National Water-Quality Assessment (NAWQA) Program. About 260 samples were collected at 51 sites during the study; of these, more than 60 percent of the pesticide samples and more than 70 percent of the nutrient samples were collected at 7 sites in a fixed-station network (primary sites) to characterize seasonal water-quality variability related to a variety of land-use activities. Samples collected at the remain ing 44 sites were used primarily to characterize spatial water- quality variability in agricultural river subbasins located throughout the study area.This report describes concentrations of 4 nutrient species (total nitrogen, filtered nitrite plus nitrate, total phosphorus, and soluble reactive phosphorus) and 86 pesticides and pesticide degradation products in streams, during high- and low-flow conditions, receiving runoff from urban, agricultural, forested, and mixed-use lands. Although most nutrient and pesticide concentrations were relatively low, some concentrations exceeded maximum contaminant levels for drinking water and water-quality criteria for chronic toxicity established for the protection of freshwater aquatic life. The largest number of exceedances generally occurred at sites receiving predominantly agricultural inputs. Total nitrogen, filtered nitrite plus nitrate, total phosphorus, and soluble reactive phosphorus concentrations were detected in 89 to 98 percent of the samples; atrazine, simazine, metolachlor, and desethylatrazine were detected in 72 to 94 percent of the samples. Fifty different pesticides and degradation products was detected during the 2-1/2 year study.Seasonally, peak nutrient and pesticide concentrations at the seven primary sites were observed during winter and spring rains. With the exception of soluble reactive phosphorus, peak nutrient concentrations were recorded at agricultural sites during winter rains, whereas peak pesticide concentrations occurred at agricultural sites during spring rains.Spatially, although nutrients were detected slightly more often in samples from the northern Willamette Basin relative to the southern Willamette Basin, concentration distributions in the two areas were similar. About 75 percent more pesticides were detected in the northern basin; however, two-thirds of the pesticide detections in the southern basin were larger in concentration than for the same pesticides detected in the northern basin.Nutrient and pesticide concentrations were associated with percent of upstream drainage area in forest, urbanization, and agriculture. Nutrient concentrations at forested sites were among the smallest observed at any of the sites sampled. In addition, only one pesticide and one pesticide degradation product were detected at forested sites, at concentrations near the method detection limits. The highest nutrient concentrations were observed at agricultural sites. Further, the largest numbers of different pesticides detected were at agricultural sites, at concentrations generally larger than at most other land-use sites. Three pesticides--dichlobenil, prometon, and tebuthiuron--were detected more frequently at a site receiving predominantly urban inputs.

Method of and apparatus for measuring the mean concentration of thoron and/or radon in a gas mixture

DOEpatents

Lucas, Henry

1990-01-01

A method of and an apparatus for detecting and accurately measuring the mean concentrations of .sup.222 Rn and .sup.220 Tn in a gas mixture, such as the ambient atmosphere in a mine, is provided. The apparatus includes an alpha target member which defines at least one operative target surface and which is preferably fabricated from a single piece of an alpha particle sensitive material. At least one portion of the operative target surface is covered with an alpha particle filter. The uncovered and filter covered operative surface is exposed to the gas mixture containing the .sup.222 Rn and .sup.220 Tn. In the radioactive decay series of these isotopes the maximum kinetic energy emitted by the alpha decay of .sup.222 Rn is about 1.1 MeV less than the maximum kinetic energy emitted by the alpha decay of a .sup.220 Tn. The alpha particle filter has a predetermined mass per unit area of the covered portion of the operative target surface that prevents penetration of alpha particles which originate from .sup.222 Rn decay, but which allows passage therethrough of the maximum kinetic energy alpha particles from .sup.220 Tn decay. Thus, a count of the alpha particle tracks in the uncovered portion of the target member is proportional to the mean concentration of sum of .sup.222 Rn and .sup.220 Tn in the gas mixture, while the count of alpha tracks in the target member under the filter is proportional to the concentration of only the .sup.220 Tn in the gas mixture.

Methamphetamine and amphetamine isomer concentrations in human urine following controlled Vicks VapoInhaler administration.

PubMed

Smith, Michael L; Nichols, Daniel C; Underwood, Paula; Fuller, Zachary; Moser, Matthew A; Flegel, Ron; Gorelick, David A; Newmeyer, Matthew N; Concheiro, Marta; Huestis, Marilyn A

2014-10-01

Legitimate use of legal intranasal decongestants containing l-methamphetamine may complicate interpretation of urine drug tests positive for amphetamines. Our study hypotheses were that commonly used immunoassays would produce no false-positive results and a recently developed enantiomer-specific gas chromatography-mass spectrometry (GC-MS) procedure would find no d-amphetamine or d-methamphetamine in urine following controlled Vicks VapoInhaler administration at manufacturer's recommended doses. To evaluate these hypotheses, 22 healthy adults were each administered one dose (two inhalations in each nostril) of a Vicks VapoInhaler every 2 h for 10 h on Day 1 (six doses), followed by a single dose on Day 2. Every urine specimen was collected as an individual void for 32 h after the first dose and assayed for d- and l-amphetamines specific isomers with a GC-MS method with >99% purity of R-(-)-α-methoxy-α-(trifluoromethyl)phenylacetyl derivatives and 10 µg/L lower limits of quantification. No d-methamphetamine or d-amphetamine was detected in any urine specimen by GC-MS. The median l-methamphetamine maximum concentration was 62.8 µg/L (range: 11.0-1,440). Only two subjects had detectable l-amphetamine, with maximum concentrations coinciding with l-methamphetamine peak levels, and always ≤ 4% of the parent's maximum. Three commercial immunoassays for amphetamines EMIT(®) II Plus, KIMS(®) II and DRI(®) had sensitivities, specificities and efficiencies of 100, 97.8, 97.8; 100, 99.6, 99.6 and 100, 100, 100%, respectively. The immunoassays had high efficiencies, but our first hypothesis was not affirmed. The EMIT(®) II Plus assay produced 2.2% false-positive results, requiring an enantiomer-specific confirmation. Published by Oxford University Press 2014. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Tetrodotoxin Concentrations in Pleurobranchaea maculata: Temporal, Spatial and Individual Variability from New Zealand Populations

PubMed Central

Wood, Susanna A.; Taylor, David I.; McNabb, Paul; Walker, Jarrod; Adamson, Janet; Cary, Stephen Craig

2012-01-01

Tetrodotoxin (TTX) is a potent neurotoxin that has been identified in a range of phylogenetically unrelated marine and terrestrial organisms. Tetrodotoxin was recently detected in New Zealand in Pleurobranchaea maculata (the grey side-gilled sea slug). From June 2010 to June 2011 wild specimens were collected from 10 locations around New Zealand. At one site (Narrow Neck Beach, Auckland) up to 10 individuals were collected monthly for 6 months. Attempts were also made to rear P. maculata in captivity. Tetrodotoxin was detected in samples from eight of the ten sites. The highest average (368.7 mg kg−1) and maximum (1414.0 mg kg−1) concentrations were measured in samples from Illiomama Rock (Auckland). Of the toxic populations tested there was significant variability in TTX concentrations among individuals, with the highest difference (62 fold) measured at Illiomama Rock. Tetrodotoxin concentrations in samples from Narrow Neck Beach varied temporally, ranging from an average of 184 mg kg−1 in June 2010 to 17.5 mg kg−1 by December 2010. There was no correlation between TTX levels and mass. The highest levels correspond with the egg laying season (June–August) and this, in concert with the detection of high levels of TTX in eggs and early larval stages, suggests that TTX may have a defensive function in P. maculata. Only one larva was successfully reared to full maturation and no TTX was detected. PMID:22363228

Distribution of pesticides and PCBs in sediments of agricultural drains in the Culiacan Valley, Sinaloa, Mexico.

PubMed

García-de la Parra, Luz María; Cervantes-Mojica, L Juleny; González-Valdivia, Carolina; Martínez-Cordero, Francisco J; Aguilar-Zárate, Gabriela; Bastidas-Bastidas, Pedro; Betancourt-Lozano, Miguel

2012-10-01

Agriculture is one of the most important economic activities in Sinaloa, Mexico. The Culiacan Valley is an extensive agricultural region characterized by a variety of crops with high-yield productions. In this study, concentrations of organochlorine (OCPs) and organophosphorus (OPs) pesticides and polychlorobiphenyls (PCBs) were determined in sediments of the agricultural drainage system of Culiacan Valley. Overall, 32 compounds were detected, with concentrations widely ranging from 0.03 to 1 294 ng g(-1) dry weight. OCP concentrations (15) ranged from 0.1 to 20.19 ng g(-1) dw. OP concentrations (8) ranged from 0.03 to 1294 ng g(-1) dw, and diazinon was the compound with the highest concentration. PCB concentrations were also determined and varied from 0.05 to 3.29 ng g(-1) dw. Other compounds detected included permethrin, triadimefon, and fipronil. The central zone registered the higher concentrations and the greatest number of compounds, which could be related to the occurrence of horticultural fields in this zone. According to sediment quality guidelines, the compounds exceeding the probable effect level were γ-HCH, p,p'-DDT and p,p'-DDE, while the pesticides above the maximum permissible concentration were endosulfan, azinphos methyl, diazinon, dichlorvos, and permethrin. Although Sinaloa is an important agricultural crop producer in northwest Mexico, there are not many studies dealing with pesticide distribution in agricultural areas.

Personal care products in wild fish in two main Chinese rivers: Bioaccumulation potential and human health risks.

PubMed

Yao, Li; Zhao, Jian-Liang; Liu, You-Sheng; Zhang, Qian-Qian; Jiang, Yu-Xia; Liu, Shan; Liu, Wang-Rong; Yang, Yuan-Yuan; Ying, Guang-Guo

2018-04-15

Personal care products (PCPs) are widely applied in our daily life, however, little is known about their occurrence in wild fish. We investigated the bioaccumulation and potential risks of 24 PCPs in muscle and liver tissues of wild fish collected from two large rivers of Pearl and Yangtze Rivers in China. The results showed the detection of a total of 13 PCPs including 9 biocides, 2 synthetic musks and 2 benzotriazoles in at least one type of fish tissue from 12 fish species. The compounds with high detection frequencies (>50%) in fish muscle or liver tissues were N,N-diethyl-3-methylbenzamide, carbendazim, climbazole, miconazole (MCZ), methylparaben, propylparaben, triclosan (TCS), tonalide, galaxolide (HHCB) and 5-methyl-1H-benzotriazole (5-TT). Among biocides, synthetic musks and benzotriazoles, TCS, HHCB and benzotriazole showed the maximum concentrations of 79.5ng/g wet weight (ww), 299ng/g ww and 3.14ng/g ww, respectively, in muscle tissue, while MCZ, HHCB and 5-TT showed the maximum concentrations of 432ng/g ww, 2619ng/g ww and 54.5ng/g ww, respectively, in liver tissue. The median values of logarithm of bioaccumulation factors (BAF) for the detected 13 PCPs were ranged 0.8-3.35 in muscle and 0.85-4.58 in liver. The log BAF values of the PCPs displayed good linear relationships with log K ow and log D ow (pH-dependent K ow ). The health hazard assessment of 10 detected PCPs in the muscle indicated no appreciable risk to human via consumption of the wild fish. Copyright © 2017 Elsevier B.V. All rights reserved.

Alcohol Dehydrogenase of Bacillus strain for Measuring Alcohol Electrochemically

NASA Astrophysics Data System (ADS)

Iswantini, D.; Nurhidayat, N.; Ferit, H.

2017-03-01

Alcohol dehydrogenase (ADH) was applied to produce alcohol biosensor. The enzyme was collected from cultured Bacillus sp. in solid media. From 6 tested isolates, bacteria from fermented rice grain (TST.A) showed the highest oxidation current which was further applied as the bioreceptor. Various ethanol concentrations was measured based on the increase of maximum oxidation current value. However, a reduction value was happened when the ethanol concentration was higher than 5%. Comparing the result of spectrophotometry measurement, R2 value obtained from the biosensor measurement method was higher. The new proposed method resulted a wider detection range, from 0.1-5% of ethanol concentration. The result showed that biosensor method has big potency to be used as alcohol detector in foods or bevearages.

Estrus behavior, ovarian dynamics, and progesterone secretion in Criollo cattle during estrous cycles with two and three follicular waves.

PubMed

Quezada-Casasola, Andrés; Avendaño-Reyes, Leonel; Macías-Cruz, Ulises; Ramírez-Godínez, José Alejandro; Correa-Calderón, Abelardo

2014-04-01

In beef and dairy cattle, the number of follicular waves affects endocrine, ovarian, and behavioral events during a normal estrous cycle. However, in Mexican-native Criollo cattle, a shortly and recently domesticated breed, the association between wave patterns and follicular development has not been studied. The objective of this study was to evaluate the effect of number of follicular waves in an estrous cycle on development of anovulatory and ovulatory follicles, corpus luteum (CL) development and functionality, as well as estrual behavior in Criollo cows. Ovarian follicular activities of 22 cycling multiparous Criollo cows were recorded daily by transrectal ultrasound examinations during a complete estrous cycle. Additionally, blood samples were collected daily to determine serum progesterone concentrations. Only two- (n = 17, 77.3%) and three-wave follicular (n = 5, 22.7%) patterns were observed. Duration of estrus, length of estrous cycle, and length of follicular and luteal phases were similar (P > 0.05) between cycles of two and three waves. Two-wave cows ovulated earlier (P < 0.05) after detection of estrus than three-wave cows. Detected day and maximum diameter of first anovulatory follicle were not affected (P > 0.05) by number of waves. Growth rate of first dominant follicle was higher (P < 0.05) in three-wave cycles. Onset of regression of the first dominant follicle was earlier (P < 0.01) in cycles with three waves than in those with two waves. In two-wave cycles, ovulatory follicles were detected earlier (P < 0.01) and had lower (P < 0.01) growth rate than in three-wave cycles. Development (i.e., maximum diameter and volume) and functionality (minimum and maximum progesterone concentration) of CL were similar (P > 0.05) between two- and three-wave patterns. In conclusion, Criollo cows have two or three follicular waves per estrous cycle, which alters partially ovulatory follicle development and ovulation time after detection of estrus. Length of estrous cycle, as well as CL development and functionality, was not affected by number of follicular waves.

Chloroform in the hydrologic system--sources, transport, fate, occurrence, and effects on human health and aquatic organisms

USGS Publications Warehouse

Ivahnenko, Tamara; Barbash, Jack E.

2004-01-01

Chloroform is one of the volatile organic compounds (VOCs) detected most frequently in both ground and surface water. Because it is also one of the four trihalomethanes (THMs) produced in the highest concentrations during the chlorination of drinking water and wastewater, the frequent detection of this compound in ground and surface water of the United States is presumed to be caused primarily by the input of chlorinated water to the hydrologic system. Although anthropogenic sources of the compound are substantial, they are currently estimated to constitute only 10 percent of the total global input to the hydrologic system. Natural sources of the compound include volcanic gases, biomass burning, marine algae, and soil microorganisms. Under most conditions (except in the presence of unusually high bromide concentrations), chloroform is the THM produced in the highest concentrations during chlorination. Furthermore, in most cases where more than one THM is produced from chlorination, the relative concentrations among the different compounds usually decrease with increasing bromination (chloroform > dichlorobromomethane > chlorodibromomethane > bromoform). This phenomenon is presumed to be responsible for the common observation that when more than one THM is detected during investigations of the occurrence of these compounds in the hydrologic system, this same trend is typically observed among their relative concentrations or, for a uniform reporting limit, their relative frequencies of detection. This pattern could provide a valuable means for distinguishing between chlorinated water and other potential sources of chloroform in the environment. Chloroform has been widely detected in national, regional, and local studies of VOCs in ground, surface, source, and drinking waters. Total THM (TTHM) concentrations of the compound, however, were typically less than the Maximum Contaminant Level (MCL) of 80 ?g/L (micrograms per liter) established by the U.S. Environmental Protection Agency (USEPA) for TTHMs. In the studies that compared land-use settings, frequencies of detection of chloroform were higher beneath urban and residential areas than beneath agricultural or undeveloped areas. Because chloroform is a suspected human carcinogen, its presence in drinking water is a potential human health concern. Liver damage, however, is known to occur at chloroform exposures lower than those required to cause cancer, an observation that has been considered by the USEPA as the basis for setting a new, non-zero Maximum Contaminant Level Goal of 70 ?g/L for the compound. As part of its National Water-Quality Assessment Program, the U.S. Geological Survey has been assembling and analyzing data on the occurrence of VOCs (including chloroform) in ground and surface water on a national scale from studies conducted between 1991 and the present. This report presents a summary of current (2004) information on the uses, sources, formation, transport, fate, and occurrence of chloroform, as well as its effects on human health and aquatic organisms.

Selected laboratory evaluations of the whole-water sample-splitting capabilities of a prototype fourteen-liter Teflon churn splitter

USGS Publications Warehouse

Horowitz, A.J.; Smith, J.J.; Elrick, K.A.

2001-01-01

A prototype 14-L Teflon? churn splitter was evaluated for whole-water sample-splitting capabilities over a range of sediment concentratons and grain sizes as well as for potential chemical contamination from both organic and inorganic constituents. These evaluations represent a 'best-case' scenario because they were performed in the controlled environment of a laboratory, and used monomineralic silica sand slurries of known concentration made up in deionized water. Further, all splitting was performed by a single operator, and all the requisite concentration analyses were performed by a single laboratory. The prototype Teflon? churn splitter did not appear to supply significant concentrations of either organic or inorganic contaminants at current U.S. Geological Survey (USGS) National Water Quality Laboratory detection and reporting limits when test samples were prepared using current USGS protocols. As with the polyethylene equivalent of the prototype Teflon? churn, the maximum usable whole-water suspended sediment concentration for the prototype churn appears to lie between 1,000 and 10,000 milligrams per liter (mg/L). Further, the maximum grain-size limit appears to lie between 125- and 250-microns (m). Tests to determine the efficacy of the valve baffle indicate that it must be retained to facilitate representative whole-water subsampling.

The effect of active recovery on power performance during the bench press exercise.

PubMed

Lopes, Felipe A S; Panissa, Valéria L G; Julio, Ursula F; Menegon, Elton M; Franchini, Emerson

2014-03-27

The objective of this study was to verify the effect of active and passive recovery on blood lactate concentration and power performance. Twelve male subjects were submitted to a maximal strength test in the the bench press, a maximal aerobic test in the bench step, and to four sets of bench press exercise performed as fast and as long as possible, using 80% of maximal strength when active or passive recovery was performed. The maximum number of repetitions, mean and peak power in eccentric and concentric phases were computed and blood lactate concentration was measured. Comparisons for the variables were made using a two-way variance analysis (recovery type and set numer) with repeated measures in the second factor. When significant differences were detected (p < 0.05), a Tukey post-hoc test was used. There was a main effect of set number on maximum number of repetitions (p < 0.05) (1 > 2, 3, and 4; 2 > 3 and 4; 3 > 4). Mean and peak power in both eccentric and concentric phases also differed across sets (1 > 2, 3, and 4; 2 > 4). There was also a main effect for the recovery type, with lower values (p < 0.05) observed for the active recovery compared to the passive one. It can be concluded that active recovery resulted in lower lactate concentration, but did not improve power performance in the bench press exercise.

The Effect of Active Recovery on Power Performance During the Bench Press Exercise

PubMed Central

Lopes, Felipe A. S.; Panissa, Valéria L. G.; Julio, Ursula F.; Menegon, Elton M.; Franchini, Emerson

2014-01-01

The objective of this study was to verify the effect of active and passive recovery on blood lactate concentration and power performance. Twelve male subjects were submitted to a maximal strength test in the the bench press, a maximal aerobic test in the bench step, and to four sets of bench press exercise performed as fast and as long as possible, using 80% of maximal strength when active or passive recovery was performed. The maximum number of repetitions, mean and peak power in eccentric and concentric phases were computed and blood lactate concentration was measured. Comparisons for the variables were made using a two-way variance analysis (recovery type and set numer) with repeated measures in the second factor. When significant differences were detected (p < 0.05), a Tukey post-hoc test was used. There was a main effect of set number on maximum number of repetitions (p < 0.05) (1 > 2, 3, and 4; 2 > 3 and 4; 3 > 4). Mean and peak power in both eccentric and concentric phases also differed across sets (1 > 2, 3, and 4; 2 > 4). There was also a main effect for the recovery type, with lower values (p < 0.05) observed for the active recovery compared to the passive one. It can be concluded that active recovery resulted in lower lactate concentration, but did not improve power performance in the bench press exercise. PMID:25031684

Arsenic in midwestern glacial deposits? Occurrence and relation to selected hydrogeologic and geochemical factors

USGS Publications Warehouse

Thomas, Mary Ann

2003-01-01

Ground-water-quality data collected as part of 12 U.S. Geological Survey National Water-Quality Assessment studies during 1996-2001 were analyzed to (1) document arsenic occurrence in four types of gla-cial deposits that occur in large areas of the Midwest, (2) identify hydrogeologic or geochemical factors asso-ciated with elevated arsenic concentrations, and (3) search for clues as to arsenic source(s) or mechanism(s) of mobilization that could be useful for designing future studies. Arsenic and other water-quality constituents were sampled in 342 monitor and domestic wells in parts of Illinois Indiana Ohio Michigan and Wisconsin. Arsenic was detected (at a concentration >1 ?g/L) in one-third of the samples. The maximum concentration was 84 ?g/L, and the median was less than 1 ?g/L. Eight percent of samples had arsenic concentrations that exceeded the U.S. Environmental Protection Agency Maximum Contaminant Level (MCL) of 10?g/L. Samples were from four aquifer types?confined valley fill, unconfined valley fill, outwash plain, and till with sand lenses. Highest arsenic concentrations were found in reducing waters from valley-fill depos-its. In confined valley fill, all waters were reducing and old (recharged before 1953), and almost half of sam-ples had arsenic concentrations greater than the MCL. In unconfined valley fill, redox conditions and ages were varied, and elevated arsenic concentrations were sporadic. In both types of valley fill, elevated arsenic concentrations are linked to the underlying bedrock on the basis of spatial relations and geochemical correla-tions. In shallow (150 ft), all deep wells were from a distinctive aquifer type (confined valley fill). It is not known whether wells at similar depths in other aquifer types would produce waters with simi-larly high arsenic concentrations. Correlations of arsenic with fluoride, strontium, and barium suggest that arsenic might be related to epi-genetic (Mississippi Valley-type) sulfide deposits in Paleozoic bedrock. Arsenic is typically released from sulfides by oxidation, but in the current study, the highest arsenic concentrations in glacial deposits were detected in reducing waters. Therefore, a link between epigenetic sulfides and elevated arsenic concentrations in glacial deposits would probably require a multi-step process.

A regional assessment of chemicals of concern in surface waters of four Midwestern United States national parks

USGS Publications Warehouse

Elliott, Sarah M.; VanderMeulen, David

2017-01-01

Anthropogenic chemicals and their potential for adverse biological effects raise concern for aquatic ecosystem health in protected areas. During 2013–15, surface waters of four Midwestern United States national parks were sampled and analyzed for wastewater indicators, pharmaceuticals, personal care products, and pesticides. More chemicals and higher concentrations were detected at the two parks with greater urban influences (Mississippi National River and Recreation Area and Indiana Dunes National Lakeshore) than at the two more remote parks (Apostle Islands National Lakeshore and Isle Royale National Park). Atrazine (10–15 ng/L) and N,N-diethyl-meta-toluamide (16–120 ng/L) were the only chemicals detected in inland lakes of a remote island national park (Isle Royale National Park). Bisphenol A and organophosphate flame retardants were commonly detected at the other sampled parks. Gabapentin and simazine had the highest observed concentrations (> 1000 ng/L) in three and two samples, respectively. At the two parks with urban influences, metolachlor and simazine concentrations were similar to those reported for other major urban rivers in the United States. Environmental concentrations of detected chemicals were often orders of magnitude less than standards or reference values with three exceptions: (1) hydrochlorothiazide exceeded a human health-based screening value in seven samples, (2) estrone exceeded a predicted critical environmental concentration for fish pharmacological effects in one sample, and (3) simazine was approaching the 4000 ng/L Maximum Contaminant Level in one sample even though this concentration is not expected to reflect peak pesticide use. Although few environmental concentrations were approaching or exceeded standards or reference values, concentrations were often in ranges reported to elicit effects in aquatic biota. Data from this study will assist in establishing a baseline for chemicals of concern in Midwestern national parks and highlight the need to better understand the sources, pathways, and potential adverse effects to aquatic systems in national parks.

A regional assessment of chemicals of concern in surface waters of four Midwestern United States national parks.

PubMed

Elliott, Sarah M; VanderMeulen, David D

2017-02-01

Anthropogenic chemicals and their potential for adverse biological effects raise concern for aquatic ecosystem health in protected areas. During 2013-15, surface waters of four Midwestern United States national parks were sampled and analyzed for wastewater indicators, pharmaceuticals, personal care products, and pesticides. More chemicals and higher concentrations were detected at the two parks with greater urban influences (Mississippi National River and Recreation Area and Indiana Dunes National Lakeshore) than at the two more remote parks (Apostle Islands National Lakeshore and Isle Royale National Park). Atrazine (10-15ng/L) and N,N-diethyl-meta-toluamide (16-120ng/L) were the only chemicals detected in inland lakes of a remote island national park (Isle Royale National Park). Bisphenol A and organophosphate flame retardants were commonly detected at the other sampled parks. Gabapentin and simazine had the highest observed concentrations (>1000ng/L) in three and two samples, respectively. At the two parks with urban influences, metolachlor and simazine concentrations were similar to those reported for other major urban rivers in the United States. Environmental concentrations of detected chemicals were often orders of magnitude less than standards or reference values with three exceptions: (1) hydrochlorothiazide exceeded a human health-based screening value in seven samples, (2) estrone exceeded a predicted critical environmental concentration for fish pharmacological effects in one sample, and (3) simazine was approaching the 4000ng/L Maximum Contaminant Level in one sample even though this concentration is not expected to reflect peak pesticide use. Although few environmental concentrations were approaching or exceeded standards or reference values, concentrations were often in ranges reported to elicit effects in aquatic biota. Data from this study will assist in establishing a baseline for chemicals of concern in Midwestern national parks and highlight the need to better understand the sources, pathways, and potential adverse effects to aquatic systems in national parks. Copyright © 2016. Published by Elsevier B.V.

Biological treatment of steroidal drug industrial effluent and electricity generation in the microbial fuel cells.

PubMed

Liu, Ru; Gao, Chongyang; Zhao, Yang-Guo; Wang, Aijie; Lu, Shanshan; Wang, Min; Maqbool, Farhana; Huang, Qing

2012-11-01

The single chamber microbial fuel cells (MFCs) were used to treat steroidal drug production wastewater (SPW) and generate electricity simultaneously. The results indicated that the maximum COD removal efficiency reached 82%, total nitrogen and sulfate removal rate approached 62.47% and 26.46%, respectively. The maximum power density and the Coulombic efficiency reached to 22.3Wm(-3) and 30%, respectively. The scanning electron microscope showed that the dominant microbial populations were remarkably different in morphology on the surface of SPW and acetate-fed anodes. PCR-denaturing gradient gel electrophoresis profiles revealed that the microbial community structure fed with different concentrations of SPW presented a gradual succession and unique bacterial sequences were detected on the SPW and acetate-fed anodes. This research demonstrates that MFCs fed with SPW achieved a high efficiency of power density and simultaneous nutrient removal, and the dominant microorganisms on the anode were related to the types and the concentrations of substrates. Copyright © 2012 Elsevier Ltd. All rights reserved.

Mid-IR absorption sensing of heavy water using a silicon-on-sapphire waveguide.

PubMed

Singh, Neetesh; Casas-Bedoya, Alvaro; Hudson, Darren D; Read, Andrew; Mägi, Eric; Eggleton, Benjamin J

2016-12-15

We demonstrate a compact silicon-on-sapphire (SOS) strip waveguide sensor for mid-IR absorption spectroscopy. This device can be used for gas and liquid sensing, especially to detect chemically similar molecules and precisely characterize extremely absorptive liquids that are difficult to detect by conventional infrared transmission techniques. We reliably measure concentrations up to 0.25% of heavy water (D₂O) in a D₂O-H₂O mixture at its maximum absorption band at around 4 μm. This complementary metal-oxide-semiconductor (CMOS) compatible SOS D₂O sensor is promising for applications such as measuring body fat content or detection of coolant leakage in nuclear reactors.

Changes of atmospheric properties over Belgrade, observed using remote sensing and in situ methods during the partial solar eclipse of 20 March 2015

NASA Astrophysics Data System (ADS)

Ilić, L.; Kuzmanoski, M.; Kolarž, P.; Nina, A.; Srećković, V.; Mijić, Z.; Bajčetić, J.; Andrić, M.

2018-06-01

Measurements of atmospheric parameters were carried out during the partial solar eclipse (51% coverage of solar disc) observed in Belgrade on 20 March 2015. The measured parameters included height of the planetary boundary layer (PBL), meteorological parameters, solar radiation, surface ozone and air ions, as well as Very Low Frequency (VLF, 3-30 kHz) and Low Frequency (LF, 30-300 kHz) signals to detect low-ionospheric plasma perturbations. The observed decrease of global solar and UV-B radiation was 48%, similar to the solar disc coverage. Meteorological parameters showed similar behavior at two measurement sites, with different elevations and different measurement heights. Air temperature change due to solar eclipse was more pronounced at the lower measurement height, showing a decrease of 2.6 °C, with 15-min time delay relative to the eclipse maximum. However, at the other site temperature did not decrease; its morning increase ceased with the start of the eclipse, and continued after the eclipse maximum. Relative humidity at both sites remained almost constant until the eclipse maximum and then decreased as the temperature increased. The wind speed decreased and reached minimum 35 min after the last contact. The eclipse-induced decrease of PBL height was about 200 m, with minimum reached 20 min after the eclipse maximum. Although dependent on UV radiation, surface ozone concentration did not show the expected decrease, possibly due to less significant influence of photochemical reactions at the measurement site and decline of PBL height. Air-ion concentration decreased during the solar eclipse, with minimum almost coinciding with the eclipse maximum. Additionally, the referential Line-of-Sight (LOS) radio link was set in the area of Belgrade, using the carrier frequency of 3 GHz. Perturbation of the receiving signal level (RSL) was observed on March 20, probably induced by the solar eclipse. Eclipse-related perturbations in ionospheric D-region were detected based on the VLF/LF signal variations, as a consequence of Lyα radiation decrease.

Occurrence of aflatoxin M₁ in commercial pasteurized milk samples in Sari, Mazandaran province, Iran.

PubMed

Mohammadi, Hamidreza; Shokrzadeh, Mohammad; Aliabadi, Zahra; Riahi-Zanjani, Bamdad

2016-05-01

The frequency and levels of aflatoxin M1 (AFM1) in pasteurized milk samples in Sari, located in Mazandaran province, Iran, were determined by enzyme immunoassay. Seventy-six samples of pasteurized milk from different retail stores were randomly collected over four seasons during the year 2015. AFM1 contamination was detected in all milk samples. The mean concentration of aflatoxin M1 was 65.8 ng/l, with a range of 11.7-106.6 ng/l. The highest AFM1 level was detected in milk samples collected during spring. Forty-six (60.53 %) samples had AFM1 levels that exceeded the maximum acceptable levels (50 ng/l) recommended by the European Union (EU). Comparison of these results with previously published data for AFM1 in milk in Iran shows that the percentage of samples exceeding the EU maximum level is consistently high over the years, indicating a general problem related to AFB1 contamination in dairy feedingstuff.

Widespread occurrence of neonicotinoid insecticides in streams in a high corn and soybean producing region, USA

USGS Publications Warehouse

Hladik, Michelle; Kolpin, Dana W.; Kuivila, Kathryn

2014-01-01

Neonicotinoid insecticides are of environmental concern, but little is known about their occurrence in surface water. An area of intense corn and soybean production in the Midwestern United States was chosen to study this issue because of the high agricultural use of neonicotinoids via both seed treatments and other forms of application. Water samples were collected from nine stream sites during the 2013 growing season. The results for the 79 water samples documented similar patterns among sites for both frequency of detection and concentration (maximum:median) with clothianidin (75%, 257 ng/L:8.2 ng/L) > thiamethoxam (47%, 185 ng/L: imidacloprid (23%, 42.7 ng/L: <2 ng/L). Neonicotinoids were detected at all nine sites sampled even though the basin areas spanned four orders of magnitude. Temporal patterns in concentrations reveal pulses of neonicotinoids associated with rainfall events during crop planting, suggesting seed treatments as their likely source.

Heavy metal concentrations in cocoa beans (Theobroma cacao L.) originating from East Luwu, South Sulawesi, Indonesia

NASA Astrophysics Data System (ADS)

Assa, A.; Noor, A.; Yunus, M. R.; Misnawi; Djide, M. N.

2018-03-01

Concentrations of some heavy metals (Pb, Cu, Cd, As and Hg) were assessed for cocoa beans (Theobroma cacao L) originating from East Luwu, South Sulawesi, Indonesia after five-day fermentation. Consisting of PB 123, BR 25, and MCC 02 cocoa clones, the spectrophotometric analysis showed that concentrations of Pb, Cd, As and Hg in the cocoa beans over the three clones was below the detection limits of 0.100; 0.050, 0.010 and 0.005 mg/kg. For Cu, they were 19.343; 10.391, and 18.594 mg/kg respectively, but still below the maximum critical levels, established by the European Food Safety Authority (EFSA). Concentrations of those five heavy metals in the bean shells were found to be parallel to those in the cocoa beans, except for Pb.

Mixing and residence times of stormwater runoff in a detection system

USGS Publications Warehouse

Martin, Edward H.

1989-01-01

Five tracer runs were performed on a detention pond and wetlands system to determine mixing and residence times in the system. The data indicate that at low discharges and with large amounts of storage, the pond is moderately mixed with residence times not much less than the theoretical maximum possible under complete mixing. At higher discharges and with less storage in the pond, short-circuiting occurs, reducing the amount of mixing in the pond and appreciably reducing the residence times. The time between pond outlet peak concentrations and wetlands outlet peak concentrations indicate that in the wetlands, mixing increases with decreasing discharge and increasing storage.

Hydrogel-Forming Microneedle Arrays Allow Detection of Drugs and Glucose In Vivo: Potential for Use in Diagnosis and Therapeutic Drug Monitoring

PubMed Central

Caffarel-Salvador, Ester; Brady, Aaron J.; Eltayib, Eyman; Meng, Teng; Alonso-Vicente, Ana; Gonzalez-Vazquez, Patricia; Torrisi, Barbara M.; Vicente-Perez, Eva Maria; Mooney, Karen; Jones, David S.; Bell, Steven E. J.; McCoy, Colin P.; McCarthy, Helen O.; McElnay, James C.; Donnelly, Ryan F.

2015-01-01

We describe, for the first time the use of hydrogel-forming microneedle (MN) arrays for minimally-invasive extraction and quantification of drug substances and glucose from skin in vitro and in vivo. MN prepared from aqueous blends of hydrolysed poly(methyl-vinylether-co-maleic anhydride) (11.1% w/w) and poly(ethyleneglycol) 10,000 daltons (5.6% w/w) and crosslinked by esterification swelled upon skin insertion by uptake of fluid. Post-removal, theophylline and caffeine were extracted from MN and determined using HPLC, with glucose quantified using a proprietary kit. In vitro studies using excised neonatal porcine skin bathed on the underside by physiologically-relevant analyte concentrations showed rapid (5 min) analyte uptake. For example, mean concentrations of 0.16 μg/mL and 0.85 μg/mL, respectively, were detected for the lowest (5 μg/mL) and highest (35 μg/mL) Franz cell concentrations of theophylline after 5 min insertion. A mean concentration of 0.10 μg/mL was obtained by extraction of MN inserted for 5 min into skin bathed with 5 μg/mL caffeine, while the mean concentration obtained by extraction of MN inserted into skin bathed with 15 μg/mL caffeine was 0.33 μg/mL. The mean detected glucose concentration after 5 min insertion into skin bathed with 4 mmol/L was 19.46 nmol/L. The highest theophylline concentration detected following extraction from a hydrogel-forming MN inserted for 1 h into the skin of a rat dosed orally with 10 mg/kg was of 0.363 μg/mL, whilst a maximum concentration of 0.063 μg/mL was detected following extraction from a MN inserted for 1 h into the skin of a rat dosed with 5 mg/kg theophylline. In human volunteers, the highest mean concentration of caffeine detected using MN was 91.31 μg/mL over the period from 1 to 2 h post-consumption of 100 mg Proplus® tablets. The highest mean blood glucose level was 7.89 nmol/L detected 1 h following ingestion of 75 g of glucose, while the highest mean glucose concentration extracted from MN was 4.29 nmol/L, detected after 3 hours skin insertion in human volunteers. Whilst not directly correlated, concentrations extracted from MN were clearly indicative of trends in blood in both rats and human volunteers. This work strongly illustrates the potential of hydrogel-forming MN in minimally-invasive patient monitoring and diagnosis. Further studies are now ongoing to reduce clinical insertion times and develop mathematical algorithms enabling determination of blood levels directly from MN measurements. PMID:26717198

The influence of Actinobacillus pleuropneumoniae infection on tulathromycin pharmacokinetics and lung tissue disposition in pigs.

PubMed

Gajda, A; Bladek, T; Jablonski, A; Posyniak, A

2016-04-01

A tulathromycin concentration and pharmacokinetic parameters in plasma and lung tissue from healthy pigs and Actinobacillus pleuropneumoniae (App)-infected pigs were compared. Tulathromycin was administered intramuscularly (i.m.) to all pigs at a single dose of 2.5 mg/kg. Blood and lung tissue samples were collected during 33 days postdrug application. Tulathromycin concentration in plasma and lung was determined by high-performance liquid chromatography with tandem mass spectrometry (LC-MS/MS) method. The mean maximum plasma concentration (Cmax ) in healthy pigs was 586 ± 71 ng/mL, reached by 0.5 h, while the mean value for Cmax of tulathromycin in infected pigs was 386 ± 97 ng/mL after 0.5 h. The mean maximum tulathromycin concentration in lung of healthy group was calculated as 3412 ± 748 ng/g, detected at 12 h, while in pigs with App, the highest concentration in lung was 3337 ± 937 ng/g, determined at 48 h postdosing. The higher plasma and lung concentrations in pigs with no pulmonary inflammation were observed at the first time points sampling after tulathromycin administration, but slower elimination with elimination half-life t1/2el  = 126 h in plasma and t1/2el  = 165 h in lung, as well as longer drug persistent in infected pigs, was found. © 2015 John Wiley & Sons Ltd.

First-pass metabolism of decursin, a bioactive compound of Angelica gigas, in rats.

PubMed

Park, Hyun Seo; Kim, Byunghyun; Oh, Ju-Hee; Kim, Young Choong; Lee, Young-Joo

2012-06-01

Decursin is considered the major bioactive compound of Angelica gigas roots, a popular Oriental herb and dietary supplement. In this study, the pharmacokinetics of decursin and its active metabolite, decursinol, were evaluated after the administration of decursin in rats. The plasma concentration of decursin decreased rapidly, with an initial half-life of 0.05 h. It was not detectable at 1 h after intravenous administration at an area under the plasma concentration-time curve of 1.20 µg · mL-1·h, whereas the concentration of decursinol increased rapidly reaching a maximum concentration of 2.48 µg · mL-1 at the time to maximum plasma concentration of 0.25 h and an area under the plasma concentration-time curve of 5.23 µg · mL-1·h. Interestingly, after oral administration of decursin, only decursinol was present in plasma, suggesting an extensive hepatic first-pass metabolism of decursin. The extremely low bioavailability of decursin after its administration via the hepatic portal vein (the fraction of dose escaping first-pass elimination in the liver, FH = 0.11) is indicative of extensive hepatic first-pass metabolism of decursin, which was confirmed by a tissue distribution study. These findings suggest that decursin is not directly associated with the bioactivity of A. gigas and that it may work as a type of natural prodrug of decursinol. Georg Thieme Verlag KG Stuttgart · New York.

Assessing atmospheric concentration of polychlorinated biphenyls by evergreen Rhododendron maximum next to a contaminated stream.

PubMed

Dang, Viet D; Walters, David M; Lee, Cindy M

2016-09-01

Conifers are often used as an air passive sampler, but few studies have focused on the implication of broadleaf evergreens to monitor atmospheric semivolatile organic compounds such as polychlorinated biphenyls (PCBs). In the present study, the authors used Rhododendron maximum (rhododendron) growing next to a contaminated stream to assess atmospheric PCB concentrations. The present study area was located in a rural setting and approximately 2 km downstream of a former capacitor plant. Leaves from the same mature shrubs were collected in late fall 2010 and winter and spring 2011. Polychlorinated biphenyls were detected in the collected leaves, suggesting that rhododendron can be used as air passive samplers in rural areas where active sampling is impractical. Estimated ΣPCB (47 congeners) concentrations in the atmosphere decreased from fall 2010 to spring 2011 with concentration means at 3990 pg m(-3) , 2850 pg m(-3) , and 931 pg m(-3) in fall 2010, winter 2011, and spring 2011, respectively. These results indicate that the atmospheric concentrations at this location continue to be high despite termination of active discharge from the former industrial source. Leaves had a consistent pattern of high concentrations of tetra-CBs and penta-CBs similar to the congener distribution in polyethylene passive samplers deployed in the water column, suggesting that volatilized PCBs from the stream were the primary source of contaminants in rhododendron leaves. Environ Toxicol Chem 2016;35:2192-2198. © 2016 SETAC. © 2016 SETAC.

Genomic copy concentrations of selected waterborne viruses in a slum environment in Kampala, Uganda.

PubMed

Katukiza, A Y; Temanu, H; Chung, J W; Foppen, J W A; Lens, P N L

2013-06-01

The presence of viruses in a slum environment where sanitation is poor is a major concern. However, little is known of their occurrence and genomic copy concentration in the slum environment. The main objective of this study was to determine the genomic copy concentrations of human adenoviruses F and G, Rotavirus (RV), Hepatitis A virus (HAV), Hepatitis E virus (HEV) and human adenovirus species A,C,D,E, and F (HAdV-ACDEF) in Bwaise III, a typical slum in Kampala, Uganda. Forty-one samples from surface water, grey water and ground water were collected from 30 sampling locations. The virus particles were recovered by glass wool filtration with elution using beef extract. DNA and RNA viruses were detected by the real time quantitative polymerase chain reaction (qPCR) and the reverse transcription-qPCR (RT-qPCR), respectively. HAdV-F and G were detected in 70.7% of the samples with concentrations up to 2.65 × 10(1) genomic copies per mL (gc mL(-1)). RV and HAV were detected in 60.9% and 17.1% of the samples, respectively. The maximum concentration of RV was 1.87 × 10(2)gc mL(-1). In addition, 78% of the samples tested positive for the HAdV-ACDEF, but all samples tested negative for HEV. These new data are essential for quantitative microbial risk assessment, and for understanding the effects of environmental pollution in slums.

Heavily boron-doped Si layers grown below 700 C by molecular beam epitaxy using a HBO2 source

NASA Technical Reports Server (NTRS)

Lin, T. L.; Fathauer, R. W.; Grunthaner, P. J.

1989-01-01

Boron doping in Si layers grown by molecular beam epitaxy (MBE) at 500-700 C using an HBO2 source has been studied. The maximum boron concentration without detectable oxygen incorporation for a given substrate temperature and Si growth rate has been determined using secondary-ion mass spectrometry analysis. Boron present in the Si MBE layers grown at 550-700 C was found to be electrically active, independent of the amount of oxygen incorporation. By reducing the Si growth rate, highly boron-doped layers have been grown at 600 C without detectable oxygen incorporation.

Distribution of ingested americium in chickens and transport to eggs. Final report, 1975

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mullen, A.A.; Lloyd, S.R.; Mosley, R.E.

1976-05-01

The soluble citrate complex of americium-241 was orally administered to 20 white Leghorn laying hens daily for two weeks. The yolks, whites, and shells from the eggs were analyzed for their americium content. Yolk was the only egg fraction in which radioactivity was observed. The americium-241 activity in yolks reached a maximum on the 14th day of dosing. Biological half-times of 2.00 plus or minus 0.18 days and greater than 33 days were indicated by the average concentration values of americium-241 in yolks laid after the maximum activity was reached. The hens were serially sacrificed at 1, 10, and 20more » days after the final administration of americium-241. Tissue samples were collected and the americium content determined in the edible portions and feathers of the hens. Americium was detected in most tissues shortly after dosing; the main concentrations were found in the liver and the skeleton. The highest concentration per organ (3.03 X 0.001 percent of the dose) occurred in the liver of the hens sacrificed 10 days after final administration of americium-241. (GRA)« less

Enzyme-functionalized thin-cladding long-period fiber grating in transition mode at dispersion turning point for sugar-level and glucose detection

NASA Astrophysics Data System (ADS)

Badmos, Abdulyezir A.; Sun, Qizhen; Sun, Zhongyuan; Zhang, Junxi; Yan, Zhijun; Lutsyk, Petro; Rozhin, Alex; Zhang, Lin

2017-02-01

Enzyme-functionalized dual-peak long-period fiber grating (LPFG) inscribed in 80-μm-cladding B/Ge codoped single-mode fiber is presented for sugar-level and specific glucose detection. Before enzyme functionalization, the dual-peak LPFG was employed for refractive index sensing and sugar-level detection and high sensitivities of ˜4298.20 nm/RIU and 4.6696 nm/% were obtained, respectively. Glucose detection probe was attained by surface functionalization of the dual-peak LPFG via covalent binding with aminopropyl triethoxysilane used as a binding site. Optical micrographs confirmed the presence of enzyme. The surface-functionalized dual-peak LPFG was tested with D-(+)-glucose solution of different concentrations. While the peak 2 at the longer wavelength was suitable only to measure lower glucose concentration (0.1 to 1.6 mg/ml) recording a high sensitivity of 12.21±0.19 nm/(mg/ml), the peak 1 at the shorter wavelength was able to measure a wider range of glucose concentrations (0.1 to 3.2 mg/ml) exhibiting a maximum resonance wavelength shift of 7.12±0.12 nm/mg/ml. The enzyme-functionalized dual-peak LPFG has the advantage of direct inscription of highly sensitive grating structures in thin-cladding fibre without etching, and most significantly, its sensitivity improvement of approximately one order of magnitude higher than previously reported LPFG and excessively tilted fibre grating (Ex-TFG) for glucose detection.

Transfer of glyphosate and its degradate AMPA to surface waters through urban sewerage systems.

PubMed

Botta, Fabrizio; Lavison, Gwenaëlle; Couturier, Guillaume; Alliot, Fabrice; Moreau-Guigon, Elodie; Fauchon, Nils; Guery, Bénédicte; Chevreuil, Marc; Blanchoud, Hélène

2009-09-01

A study of glyphosate and aminomethyl phosphonic acid (AMPA) transfer in the Orge watershed (France) was carried out during 2007 and 2008. Water samples were collected in surface water, wastewater sewer, storm sewer and wastewater treatment plant (WWTP). These two molecules appeared to be the most frequently detected ones in the rivers and usually exceeded the European quality standard concentrations of 0.1microg L(-1) for drinking water. The annual glyphosate estimated load was 1.9 kg year(-1) upstream (agricultural zone) and 179.5 kg year(-1) at the catchment outlet (urban zone). This result suggests that the contamination of this basin by glyphosate is essentially from urban origin (road and railway applications). Glyphosate reached surface water prevalently through storm sewer during rainfall event. Maximum concentrations were detected in storm sewer just after a rainfall event (75-90 microg L(-1)). High concentrations of glyphosate in surface water during rainfall events reflected urban runoff impact. AMPA was always detected in the sewerage system. This molecule reached surface water mainly via WWTP effluent and also through storm sewer. Variations in concentrations of AMPA during hydrological episodes were minor compared to glyphosate variations. Our study highlights that AMPA and glyphosate origins in urban area are different. During dry period, detergent degradation seemed to be the major AMPA source in wastewater.

Pharmaceutical contamination in residential, industrial, and agricultural waste streams: risk to aqueous environments in Taiwan.

PubMed

Lin, Angela Yu-Chen; Yu, Tsung-Hsien; Lin, Cheng-Fang

2008-12-01

This is a comprehensive study of the occurrence of antibiotics, hormones and other pharmaceuticals in water sites that have major potential for downstream environmental contamination. These include residential (hospitals, sewage treatment plants, and regional discharges), industrial (pharmaceutical production facilities), and agricultural (animal husbandries and aquacultures) waste streams. We assayed 23 Taiwanese water sites for 97 targeted compounds, of which a significant number were detected and quantified. The most frequently detected compounds were sulfamethoxazole, caffeine, acetaminophen, and ibuprofen, followed closely by cephalexin, ofloxacin, and diclofenac, which were detected in >91% of samples and found to have median (maximum) concentrations of 0.2 (5.8), 0.39 (24.0), 0.02 (100.4), 0.41 (14.5), 0.15 (31.4), 0.14 (13.6) and 0.083 (29.8) microg/L, respectively. Lincomycin and acetaminophen had high measured concentrations (>100 microg/L), and 35 other pharmaceuticals occurred at the microg/L level. These incidence and concentration results correlate well with published data for other worldwide locations, as well as with Taiwanese medication usage data, suggesting a human contamination source. Many pharmaceuticals also occurred at levels exceeding predicted no-effect concentrations (PNEC), warranting further investigation of their occurrence and fate in receiving waters, as well as the overall risks they pose for local ecosystems and human residents. The information provided here will also be useful for development of strategies for regulation and remediation.

Relevance of drinking water as a source of human exposure to bisphenol A

PubMed Central

Arnold, Scott M; Clark, Kathryn E; Staples, Charles A; Klecka, Gary M; Dimond, Steve S; Caspers, Norbert; Hentges, Steven G

2013-01-01

A comprehensive search of studies describing bisphenol A (BPA) concentrations in drinking water and source waters (i.e., surface water and groundwater) was conducted to evaluate the relevance of drinking water as a source of human exposure and risk. Data from 65 papers were evaluated from North America (31), Europe (17), and Asia (17). The fraction of drinking water measurements reported as less than the detection limit is high; 95%, 48%, and 41%, for North America, Europe, and Asia, respectively. The maximum quantified (in excess of the detection limit) BPA concentrations from North America, Europe, and Asia are 0.099 μg/l, 0.014 μg/l, and 0.317 μg/l. The highest quantified median and 95th percentile concentrations of BPA in Asian drinking water are 0.026 μg/l and 0.19 μg/l, while high detection limits restricted the determination of representative median and 95th percentile concentrations in North America and Europe. BPA in drinking water represents a minor component of overall human exposure, and compared with the lowest available oral toxicity benchmark of 16 μg/kg-bw/day (includes an uncertainty factor of 300) gives margins of safety >1100. Human biomonitoring data indicate that ingestion of drinking water represents <2.8% of the total intake of BPA. PMID:22805988

Haze is an important medium for the spread of rotavirus.

PubMed

Ye, Qing; Fu, Jun-Feng; Mao, Jian-Hua; Shen, Hong-Qiang; Chen, Xue-Jun; Shao, Wen-Xia; Shang, Shi-Qiang; Wu, Yi-Feng

2016-09-01

This study investigated whether the rotavirus infection rate in children is associated with temperature and air pollutants in Hangzhou, China. This study applied a distributed lag non-linear model (DLNM) to assess the effects of daily meteorological data and air pollutants on the rotavirus positive rate among outpatient children. There was a negative correlation between temperature and the rotavirus infection rate. The impact of temperature on the detection rate of rotavirus presented an evident lag effect, the temperature change shows the greatest impact on the detection rate of rotavirus approximate at lag one day, and the maximum relative risk (RR) was approximately 1.3. In 2015, the maximum cumulative RR due to the cumulative effect caused by the temperature drop was 2.5. Particulate matter (PM) 2.5 and PM10 were the primary air pollutants in Hangzhou. The highest RR of rotavirus infection occurred at lag 1-1.5 days after the increase in the concentration of these pollutants, and the RR increased gradually with the increase in concentration. Based on the average concentrations of PM2.5 of 53.9 μg/m(3) and PM10 of 80.6 μg/m(3) in Hangzhou in 2015, the cumulative RR caused by the cumulative effect was 2.5 and 2.2, respectively. The current study suggests that temperature is an important factor impacting the rotavirus infection rate of children in Hangzhou. Air pollutants significantly increased the risk of rotavirus infection, and dosage, lag and cumulative effects were observed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Food safety aspects of primary environmental contaminants in the edible tissues of roe deer (Capreolus capreolus).

PubMed

Lehel, József; Zwillinger, Dóra; Bartha, András; Lányi, Katalin; Laczay, Péter

2017-11-01

The muscle, liver, kidney and fat samples of 20 roe deer of both sexes originating from a hunting area in central Hungary were investigated for the presence of heavy metals such as As, Cd, Hg and Pb, and their contents were evaluated for possible health risk to consumers. Both As and Hg were found at a level below the limit of detection (< 0.5 mg/kg wet weight) in all samples. The median of the measured Cd concentrations was significantly higher in both the kidney and the liver (p = 0.0011) of bucks than of does. In bucks, Cd levels exceeded the respective maximum limits laid down in the European legislation in four kidney and three muscle samples, whereas in does, the measured concentrations were below the respective limits in all samples. The detected amounts of Pb exceeded the maximum limits in the kidney of one buck and eight does, in the liver of two bucks and six does, in the muscle of six bucks and nine does, whereas in all fat tissues of both bucks and does. The concentration of Pb (p = 0.02) was significantly greater in the kidney of does compared to roebucks. Based on data obtained from the present study, the consumption of organs and tissues of the investigated roe deer could be objectionable from food-toxicological point of view and may pose risk to the high consumers of wild game due to their cadmium and lead contents.

Occurrence of anthropogenic organic compounds and nutrients in source and finished water in the Sioux Falls area, South Dakota, 2009-10

USGS Publications Warehouse

Hoogestraat, Galen K.

2012-01-01

Anthropogenic organic compounds (AOCs) in drinking-water sources commonly are derived from municipal, agricultural, and industrial wastewater sources, and are a concern for water-supply managers. A cooperative study between the city of Sioux Falls, S. Dak., and the U.S. Geological Survey was initiated in 2009 to (1) characterize the occurrence of anthropogenic organic compounds in the source waters (groundwater and surface water) to water supplies in the Sioux Falls area, (2) determine if the compounds detected in the source waters also are present in the finished water, and (3) identify probable sources of nitrate in the Big Sioux River Basin and determine if sources change seasonally or under different hydrologic conditions. This report presents analytical results of water-quality samples collected from source waters and finished waters in the Sioux Falls area. The study approach included the collection of water samples from source and finished waters in the Sioux Falls area for the analyses of AOCs, nutrients, and nitrogen and oxygen isotopes in nitrate. Water-quality constituents monitored in this study were chosen to represent a variety of the contaminants known or suspected to occur within the Big Sioux River Basin, including pesticides, pharmaceuticals, sterols, household and industrial products, polycyclic aromatic hydrocarbons, antibiotics, and hormones. A total of 184 AOCs were monitored, of which 40 AOCs had relevant human-health benchmarks. During 11 sampling visits, 45 AOCs (24 percent) were detected in at least one sample of source or finished water, and 13 AOCs were detected in at least 20 percent of all samples. Concentrations of detected AOCs were all less than 1 microgram per liter, except for two AOCs in multiple samples from the Big Sioux River, and one AOC in finished-water samples. Concentrations of AOCs were less than 0.1 microgram per liter in more than 75 percent of the detections. Nutrient concentrations varied seasonally in source-water samples from surface water and groundwater. In the Big Sioux River, nitrite plus nitrate concentrations were typically less than 1 milligram per liter as nitrogen, and reached a maximum of 4.06 milligrams per liter as nitrogen following a June 2010 storm. Nitrite plus nitrate concentrations in groundwater ranged from less than 0.1 to 0.701 milligram per liter as nitrogen. Eight of the AOCs detected have a human-health benchmark that could be used to evaluate the concentrations in a human-health context. Four AOCs had maximum concentrations within an order of magnitude of the benchmark, indicating that additional monitoring of the compound may be warranted. Three herbicides (atrazine, metolachlor, and prometon) and one degradate (deethylatrazine) were detected in finished-water samples as frequently as in source-water samples. The concentrations of herbicides in source water varied by an order of magnitude from the period of peak use (early summer) to the winter months. Groundwater and finished-water concentrations of atrazine were similar for the six sampling dates when groundwater was the only source water used. Upstream wastewater discharges contributed a fairly small percentage of the flow to the Big Sioux River near Sioux Falls, but several AOCs associated with wastewater were frequently detected. The interpretation of all potential sources of nitrogen cannot be accomplished by use of nitrogen and oxygen isotopes in nitrate alone, but provides a qualitative indication that very little nitrate originates from excess fertilizer runoff, and most nitrate originates from municipal wastewater effluent, manure runoff (either from field application or feeding operations), or fertilizers mineralized by processes in the soil.

Uranium and radon in ground water in the lower Illinois River basin

USGS Publications Warehouse

Morrow, William S.

2001-01-01

Uranium and radon are present in ground water throughout the United States, along with other naturally occurring radionuclides. The occurrence and distribution of uranium and radon are of concern because these radionuclides are carcinogens that can be ingested through drinking water. As part of the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) program, water samples were collected and analyzed for uranium and radon from 117 wells in four aquifers in the lower Illinois River Basin (LIRB) from 1996 to 1997. The aquifers were the shallow glacial drift deposits of the Bloomington Ridged Plain (BRP) not overlying a buried bedrock valley (BRP N/O BV), shallow glacial drift deposits of the BRP overlying the Mahomet Buried Bedrock Valley (BRP O/L MBBV), shallow glacial drift deposits of the Galesburg/Springfield Plain not overlying a buried bedrock valley (GSP N/O BV), and the deep glacial drift deposits of the Mahomet Buried Bedrock Valley (MBBV). Uranium was detected in water samples from all aquifers except the MBBV and ranged in concentration from less than 1 microgram per liter ( ? g/L) to 17 ? g/L. Uranium concentrations did not exceed 20 ? g/L, the proposed U.S. Environmental Protection Agency (USEPA) Maximum Contaminant Level (MCL) at the time of sampling (1996?97). The current (2001) promulgated MCL is 30 ? g/L (U.S. Environmental Protection Agency, 2000). The highest median uranium concentration (2.0 ? g/L) among the four aquifers was in the BRP N/O BV. Uranium most often occurred in oxidizing and sulfate-rich water. Radon was detected in water samples from all aquifers in the LIRB. Radon concentrations in all aquifers ranged from less than 80 picocuries per liter (pCi/L) to 1,300 pCi/L. Of 117 samples, radon concentrations exceeded 300 pCi/L (the proposed USEPA MCL) in 34 percent of the samples. Radon concentrations exceeded 300 pCi/L in more than one-half of the samples from the GSP N/O BV and the BRP O/L MBBV. No sample exceeded the proposed Alternative Maximum Contaminant Level (AMCL) of 4,000 pCi/L. Concentrations of uranium and radon were not correlated.

Factors affecting groundwater quality in the Valley and Ridge aquifers, eastern United States, 1993-2002

USGS Publications Warehouse

Johnson, Gregory C.; Zimmerman, Tammy M.; Lindsey, Bruce D.; Gross, Eliza L.

2011-01-01

Chemical and microbiological analyses of water from 230 wells and 35 springs in the Valley and Ridge Physiographic Province, sampled between 1993 and 2002, indicated that bedrock type (carbonate or siliciclastic rock) and land use were dominant factors influencing groundwater quality across a region extending from northwestern Georgia to New Jersey. The analyses included naturally occurring compounds (major mineral ions and radon) and anthropogenic contaminants [pesticides and volatile organic compounds (VOCs)], and contaminants, such as nitrate and bacteria, which commonly increase as a result of human activities. Natural factors, such as topographic position and the mineral composition of underlying geology, act to produce basic physical and geochemical conditions in groundwater that are reflected in physical properties, such as pH, temperature, specific conductance, and alkalinity, and in chemical concentrations of dissolved oxygen, radon, and major mineral ions. Anthropogenic contaminants were most commonly found in water from wells and springs in carbonate-rock aquifers. Nitrate concentrations exceeded U.S. Environmental Protection Agency maximum contaminant levels in 12 percent of samples, most of which were from carbonate-rock aquifers. Escherichia coli (E. coli), pesticide, and VOC detection frequencies were significantly higher in samples from sites in carbonate-rock aquifers. Naturally occurring elements, such as radon, iron, and manganese, were found in higher concentrations in siliciclastic-rock aquifers. Radon levels exceeded the proposed maximum contaminant level of 300 picocuries per liter in 74 percent of the samples, which were evenly distributed between carbonate- and siliciclastic-rock aquifers. The land use in areas surrounding wells and springs was another significant explanatory variable for the occurrence of anthropogenic compounds. Nitrate and pesticide concentrations were highest in samples collected from sites in agricultural areas and lowest in samples collected from sites in undeveloped areas. Volatile organic compounds were detected most frequently and in highest concentrations in samples from sites in urban areas, and least frequently in agricultural and undeveloped areas. No volatile organic compound concentrations and concentrations from only one pesticide, dieldrin, exceeded human-health benchmarks.

Potentiometric levels and water quality in the aquifers underlying Belvidere, Illinois, 1993-96

USGS Publications Warehouse

Mills, Patrick C.; Thomas, C.A.; Brown, T.A.; Yeskis, D.J.; Kay, R.T.

1999-01-01

In 1992, the U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency (USEPA), began a study of the hydrogeology and water quality of the aquifers underlying the vicinity of Belvidere, Boone County, Ill. Previously, volatile organic compounds (VOC's) and other constituents of industrial origin were detected in one or more ground-water samples from about 100 of the approximately 700 monitoring and water-supply wells in the area, including the 8 municipal wells in Belvidere. A glacial drift aquifer underlies at least 50 percent of the 80-square-mile study area; bedrock aquifers that underlie virtually all of the study area include the Galena-Platteville, St. Peter Sandstone, Ordovician, and Cambrian-Ordovician aquifers. During 1993, water levels were measured in 152 wells and water-quality samples were collected from 97 wells distributed throughout the study area. During 1994-96, similar data were collected from 31 wells. Potentiometric levels in the glacial drift and Galena-Platteville aquifers are similar and range from about 750 to 900 feet above sea level. The potentiometric surfaces of the aquifers are subdued representations of the land surface. Horizontal ground-water flow in the aquifers primarily is towards the Kishwaukee River, which flows through the central part of the study area, and its principal tributaries. Vertical ground-water flow appears to be downward at most locations in the study area, particularly in the urbanized areas affected by pumping of the Belvidere municipal wells and upland areas remote from the principal surface-water drainages. Flow appears to be upward between the Galena-Platteville and glacial drift aquifers where ground water discharges to the Kishwaukee River and its principal tributaries. All water samples were analyzed for VOC's. Selected samples also were analyzed for trace metals, cyanide, semivolatile organic compounds, or other constituents. VOC's were detected in samples from 50 wells (52 percent of total wells sampled). Twenty-seven specific VOC's were identified in the samples. Samples were collected from six municipal wells in use during the study; two wells were not in use because one or more VOC's exceeded maximum contaminant levels (MCL's). Two VOC's were detected in one of the samples at concentrations below MCL's established by the USEPA for protection of public-water supplies. Samples from 21 wells had at least one VOC detected at a concentration above MCL's. The VOC's detected above MCL's and their maximum concentrations were 1,2-dichloroethene (total), 470 micrograms per liter; trichloroethene (TCE), 360 micrograms per liter; tetrachloroethene (PCE), 82 micrograms per liter; benzene, 53 micrograms per liter; and vinyl chloride, 11 micrograms per liter. TCE and PCE were the most frequently detected VOC's and generally had the highest concentrations. VOC's with concentrations above MCL's were detected in samples from 15 wells open to the glacial drift aquifer and 6 wells open to the Galena-Platteville aquifer. Generally, the concentrations of VOC's were higher, and number and type of VOC's detected were greater in the glacial drift aquifer than in the Galena-Platteville aquifer and the deeper bedrock aquifers. The high concentrations and spatial distribution of VOC's in the glacial drift aquifer usually were related to nearby sources of contamination. Except in the immediate vicinity of a known hazardous-waste site, possible sources of VOC's in the bedrock aquifers were difficult to identify in the study area; VOC concentrations at most locations in the bedrock aquifers were below 5 micrograms per liter. Most locations where VOC's were detected in the glacial and bedrock aquifers were within about 1,000 feet of the Kishwaukee River. Hydrogeologic factors that affect the distribution of VOC's in the aquifers include ground-water flow through (1) the glacial drift aquifer with discharge to the nearby Kishwaukee River; and (2) the weathered-surface

Concentrations of nitrate in drinking water in the lower Yakima River Basin, Groundwater Management Area, Yakima County, Washington, 2017

USGS Publications Warehouse

Huffman, Raegan L.

2018-05-29

The U.S. Geological Survey, in cooperation with the lower Yakima River Basin Groundwater Management Area (GWMA) group, conducted an intensive groundwater sampling collection effort of collecting nitrate concentration data in drinking water to provide a baseline for future nitrate assessments within the GWMA. About every 6 weeks from April through December 2017, a total of 1,059 samples were collected from 156 wells and 24 surface-water drains. The domestic wells were selected based on known location, completion depth, ability to collect a sample prior to treatment on filtration, and distribution across the GWMA. The drains were pre-selected by the GWMA group, and further assessed based on ability to access sites and obtain a representative sample. More than 20 percent of samples from the domestic wells and 12.8 percent of drain samples had nitrate concentrations that exceeded the maximum contaminant level (MCL) of 10 milligrams per liter established by the U.S. Environmental Protection Agency. At least one nitrate concentration above the MCL was detected in 26 percent of wells and 33 percent of drains sampled. Nitrate was not detected in 13 percent of all samples collected.

High frequency monitoring of pesticides in runoff water from a vineyard: ecotoxicological and hysteresis pattern analysis

NASA Astrophysics Data System (ADS)

Lefrancq, Marie; Jadas-Hécart, Alain; La Jeunesse, Isabelle; Landry, David; Payraudeau, Sylvain

2017-04-01

Rainfall-induced peaks in pesticide concentrations can occur rapidly; therefore, low frequency sampling may largely underestimate maximum pesticide concentrations and fluxes. Detailed storm-based sampling of pesticide concentrations in runoff water to better predict pesticide sources, transport pathways and toxicity within the headwater catchments is actually lacking. High frequency monitoring (2 min) of dissolved concentrations and loads for seven pesticides (Dimetomorph, Fluopicolide, Glyphosate, Iprovalicarb, Tebuconazole, Tetraconazole and Triadimenol) and one degradation product (AMPA) were assessed for 20 runoff events from 2009 to 2012 at the outlet of a vineyard catchment in the Layon catchment in France. The pesticide concentrations reached 387 µg/L. All of the runoff events exceeded the mandated acceptable concentrations of 0.1 µg/L for each pesticide (European directive 2013/39/EC). High resolution sampling used to detect the peak pesticide levels revealed that Toxic Units (TU) for algae, invertebrates and fish often exceeded the European Uniform principles (25%). The instantaneous and average (time or discharge-weighted) concentrations indicated an up to 30- or 4-fold underestimation of the TU obtained when measuring the maximum concentrations, respectively, highlighting the important role of the sampling methods for assessing peak exposure. High resolution sampling combined with concentration-discharge hysteresis analyses revealed that clockwise responses were predominant (52%), indicating that Hortonian runoff is the prevailing surface runoff trigger mechanism in the study catchment. The hysteresis patterns for suspended solids and pesticides were highly dynamic and storm- and chemical-dependent. Intense rainfall events induced stronger C-Q hysteresis (magnitude). This study provides new insights into the complexity of pesticide dynamics in runoff water and highlights the ability of hysteresis analysis to improve the understanding of pesticide supply and transport.

Detection of copper, lead, cadmium and iron in wine using electronic tongue sensor system.

PubMed

Simões da Costa, A M; Delgadillo, I; Rudnitskaya, A

2014-11-01

An array of 10 potentiometric chemical sensors has been applied to the detection of total Fe, Cu, Pb and Cd content in digested wine. As digestion of organic matter of wine is necessary prior to the trace metal detection using potentiometric sensors, sample preparation procedures have been optimized. Different variants of wet and microwave digestion and dry ashing, 14 conditions in total, have been tested. Decomposition of organic matter was assessed using Fourier transform mid-infrared spectroscopy and total phenolic content. Dry ashing was found to be the most effective method of wine digestion. Measurements with sensors in individual solutions of Fe(III), Cu(II), Pb(II) and Cd(II) prepared on different backgrounds have shown that their detection limits were below typical concentration levels of these metals in wines and, in the case of Cu, Pb and Cd below maximum allowed concentrations. Detection of Fe in digested wine samples was possible using discrete iron-sensitive sensors with chalcogenide glass membranes with RMSEP of 0.05 mmol L(-1) in the concentration range from 0.0786 to 0.472 mmol L(-1). Low concentration levels of Cu, Pb and Cd in wine and cross-sensitivity of respective sensors resulted in the non-linearity of their responses, requiring back-propagation neural network for the calibration. Calibration models have been calculated using measurements in the model mixed solutions containing all three metals and a set of digested wine sample. RMSEP values for Cu, Pb and Cd were 3.9, 39 and 1.2 μmol L(-1) in model solutions and 2, 150 and 1 μmol L(-1) in digested wine samples. Copyright © 2014 Elsevier B.V. All rights reserved.

Pesticide Residues on Three Cut Flower Species and Potential Exposure of Florists in Belgium.

PubMed

Toumi, Khaoula; Vleminckx, Christiane; van Loco, Joris; Schiffers, Bruno

2016-09-23

In order to assess the prevalence of pesticide contamination and the risk of florists' exposure when handling cut flowers, sampling and analysis of 90 bouquets of the most commonly sold cut flowers in Belgium (50 bouquets of roses; 20 of gerberas, and 20 of chrysanthemums) were carried out. The bouquets were collected from 50 florists located in the seven largest cities of Belgium (Antwerp, Brussels, Charleroi, Ghent, Leuven, Liege, and Namur) and from five supermarkets located in the different regions. To have a better understanding of the route of exposure and professional practices a questionnaire was also addressed to a group of 25 florists who volunteered to take part in the survey. All florists were interviewed individually when collecting the questionnaire. The residual pesticide deposit values on cut flowers were determined in an accredited laboratory using a multi-residue (QuEChERS Quick Easy Cheap Effective Rugged Safe) method and a combination of gas chromatography (GC) and liquid chormatograhphy (LC) analysis. A total of 107 active substances were detected from all samples; i.e., an average of about 10 active substances per bouquet. The most severely contaminated bouquet accumulated a total concentration of residues up to 97 mg/kg. Results show that roses are the most contaminated cut flowers; with an average of 14 substances detected per sample and a total concentration per rose sample of 26 mg/kg. Some active substances present an acute toxicity (acephate, methiocarb, monocrotophos, methomyl, deltamethrin, etc.) and exposure can generate a direct effect on the nervous system of florists. Nevertheless, fungicides (dodemorph, propamocarb, and procymidone) were the most frequently detected in samples and had the highest maximum concentrations out of all the active substances analysed. Dodemorph was the most frequently detected substance with the highest maximum concentration (41.9 mg/kg) measured in the rose samples. It appears from the survey that, despite being exposed to high deposits of residues, florists usually do not protect themselves from contact with residues even if they spend several hours handling cut flowers and preparing bouquets (from 2 to 6 h/day, depending on the time of year and/or selling periods) daily. Bad habits (eating, drinking, or smoking at work) and absence of personal protective equipment of most florists also increase the risk of contact with pesticide residues.

Pesticide Residues on Three Cut Flower Species and Potential Exposure of Florists in Belgium

PubMed Central

Toumi, Khaoula; Vleminckx, Christiane; van Loco, Joris; Schiffers, Bruno

2016-01-01

In order to assess the prevalence of pesticide contamination and the risk of florists’ exposure when handling cut flowers, sampling and analysis of 90 bouquets of the most commonly sold cut flowers in Belgium (50 bouquets of roses; 20 of gerberas, and 20 of chrysanthemums) were carried out. The bouquets were collected from 50 florists located in the seven largest cities of Belgium (Antwerp, Brussels, Charleroi, Ghent, Leuven, Liege, and Namur) and from five supermarkets located in the different regions. To have a better understanding of the route of exposure and professional practices a questionnaire was also addressed to a group of 25 florists who volunteered to take part in the survey. All florists were interviewed individually when collecting the questionnaire. The residual pesticide deposit values on cut flowers were determined in an accredited laboratory using a multi-residue (QuEChERS Quick Easy Cheap Effective Rugged Safe) method and a combination of gas chromatography (GC) and liquid chormatograhphy (LC) analysis. A total of 107 active substances were detected from all samples; i.e., an average of about 10 active substances per bouquet. The most severely contaminated bouquet accumulated a total concentration of residues up to 97 mg/kg. Results show that roses are the most contaminated cut flowers; with an average of 14 substances detected per sample and a total concentration per rose sample of 26 mg/kg. Some active substances present an acute toxicity (acephate, methiocarb, monocrotophos, methomyl, deltamethrin, etc.) and exposure can generate a direct effect on the nervous system of florists. Nevertheless, fungicides (dodemorph, propamocarb, and procymidone) were the most frequently detected in samples and had the highest maximum concentrations out of all the active substances analysed. Dodemorph was the most frequently detected substance with the highest maximum concentration (41.9 mg/kg) measured in the rose samples. It appears from the survey that, despite being exposed to high deposits of residues, florists usually do not protect themselves from contact with residues even if they spend several hours handling cut flowers and preparing bouquets (from 2 to 6 h/day, depending on the time of year and/or selling periods) daily. Bad habits (eating, drinking, or smoking at work) and absence of personal protective equipment of most florists also increase the risk of contact with pesticide residues. PMID:27669276

Ground-Water Quality and Potential Effects of Individual Sewage Disposal System Effluent on Ground-Water Quality in Park County, Colorado, 2001-2004

USGS Publications Warehouse

Miller, Lisa D.; Ortiz, Roderick F.

2007-01-01

In 2000, the U.S. Geological Survey, in cooperation with Park County, Colorado, began a study to evaluate ground-water quality in the various aquifers in Park County that supply water to domestic wells. The focus of this study was to identify and describe the principal natural and human factors that affect ground-water quality. In addition, the potential effects of individual sewage disposal system (ISDS) effluent on ground-water quality were evaluated. Ground-water samples were collected from domestic water-supply wells from July 2001 through October 2004 in the alluvial, crystalline-rock, sedimentary-rock, and volcanic-rock aquifers to assess general ground-water quality and effects of ISDS's on ground-water quality throughout Park County. Samples were analyzed for physical properties, major ions, nutrients, bacteria, and boron; and selected samples also were analyzed for dissolved organic carbon, human-related (wastewater) compounds, trace elements, radionuclides, and age-dating constituents (tritium and chlorofluorocarbons). Drinking-water quality is adequate for domestic use throughout Park County with a few exceptions. Only about 3 percent of wells had concentrations of fluoride, nitrate, and (or) uranium that exceeded U.S. Environmental Protection Agency national, primary drinking-water standards. These primary drinking-water standards were exceeded only in wells completed in the crystalline-rock aquifers in eastern Park County. Escherichia coli bacteria were detected in one well near Guffey, and total coliform bacteria were detected in about 11 percent of wells sampled throughout the county. The highest total coliform concentrations were measured southeast of the city of Jefferson and west of Tarryall Reservoir. Secondary drinking-water standards were exceeded more frequently. About 19 percent of wells had concentrations of one or more constituents (pH, chloride, fluoride, sulfate, and dissolved solids) that exceeded secondary drinking-water standards. Currently (2004), there is no federally enforced drinking-water standard for radon in public water-supply systems, but proposed regulations suggest a maximum contaminant level of 300 picocuries per liter (pCi/L) and an alternative maximum contaminant level of 4,000 pCi/L contingent on other mitigating remedial activities to reduce radon levels in indoor air. Radon concentrations in about 91 percent of ground-water samples were greater than or equal to 300 pCi/L, and about 25 percent had radon concentrations greater than or equal to 4,000 pCi/L. Generally, the highest radon concentrations were measured in samples collected from wells completed in the crystalline-rock aquifers. Analyses of ground-water-quality data indicate that recharge from ISDS effluent has affected some local ground-water systems in Park County. Because roughly 90 percent of domestic water used is assumed to be recharged by ISDS's, detections of human-related (wastewater) compounds in ground water in Park County are not surprising; however, concentrations of constituents associated with ISDS effluent generally are low (concentrations near the laboratory reporting levels). Thirty-eight different organic wastewater compounds were detected in 46 percent of ground-water samples, and the number of compounds detected per sample ranged from 1 to 17 compounds. Samples collected from wells with detections of wastewater compounds also had significantly higher (p-value < 0.05) chloride and boron concentrations than samples from wells with no detections of wastewater compounds. ISDS density (average subdivision lot size used to estimate ISDS density) was related to ground-water quality in Park County. Chloride and boron concentrations were significantly higher in ground-water samples collected from wells located in areas that had average subdivision lot sizes of less than 1 acre than in areas that had average subdivision lot sizes greater than or equal to 1 acre. For wells completed in the crystalline-

Assessment of Hyporheic Zone, Flood-Plain, Soil-Gas, Soil, and Surface-Water Contamination at the McCoys Creek Chemical Training Area, Fort Gordon, Georgia, 2009-2010

USGS Publications Warehouse

Guimaraes, Wladmir B.; Falls, W. Fred; Caldwell, Andral W.; Ratliff, W. Hagan; Wellborn, John B.; Landmeyer, James E.

2011-01-01

The U.S. Geological Survey, in cooperation with the U.S. Department of the Army Environmental and Natural Resources Management Office of the U.S. Army Signal Center and Fort Gordon, Georgia, assessed the hyporheic zone, flood plain, soil gas, soil, and surface water for contaminants at the McCoys Creek Chemical Training Area (MCTA) at Fort Gordon, from October 2009 to September 2010. The assessment included the detection of organic contaminants in the hyporheic zone, flood plain, soil gas, and surface water. In addition, the organic contaminant assessment included the analysis of organic compounds classified as explosives and chemical agents in selected areas. Inorganic contaminants were assessed in soil and surface-water samples. The assessment was conducted to provide environmental contamination data to the U.S. Army at Fort Gordon pursuant to requirements of the Resource Conservation and Recovery Act Part B Hazardous Waste Permit process. Ten passive samplers were deployed in the hyporheic zone and flood plain, and total petroleum hydrocarbons (TPH) and octane were detected above the method detection level in every sampler. Other organic compounds detected above the method detection level in the hyporheic zone and flood-plain samplers were trichloroethylene, and cis- and trans- 1, 2-dichloroethylene. One trip blank detected TPH below the method detection level but above the nondetection level. The concentrations of TPH in the samplers were many times greater than the concentrations detected in the blank; therefore, all other TPH concentrations detected are considered to represent environmental conditions. Seventy-one soil-gas samplers were deployed in a grid pattern across the MCTA. Three trip blanks and three method blanks were used and not deployed, and TPH was detected above the method detection level in two trip blanks and one method blank. Detection of TPH was observed at all 71 samplers, but because TPH was detected in the trip and method blanks, TPH was censored and, therefore, only 7 of the 71 samplers were reported as detecting TPH. In addition, benzene, toluene, ethylbenzene, and total xylene were detected above the method detection level in 22 samplers. Other compounds detected above the method detection level included naphthalene, octane, undecane, tridecane, 1,2,4-trimethylbenzene, trichloroethylene, perchloroethylene, chloroform, and 1,4-dichlorobenzene. Subsequent to the soil-gas survey, five locations with elevated contaminant mass were selected and a passive sampler was deployed at those locations to detect the presence of organic compounds classified as explosives or chemical agents. No explosives or chemical agents were detected above the method detection level, but some compounds were detected below the method detection level but above the nondetection level. Dimethyl disulfide, benzothiazole, chloroacetophenones, and para-chlorophenyl methyl sulfide were all detected below the method detection level but above the nondetection level. The compounds 2,4-dinitrotoluene, and para-chlorophenyl methyl sulfone were detected in samplers but also were detected in trip blanks and are not considered as present in the MCTA. The same five locations that were selected for sampling of explosives and chemical agents were selected for soil sampling. Metal concentrations in composite soil samples collected at five locations from land surface to a depth of 6 inches did not exceed the U.S. Environmental Protection Agency Regional Screening Levels for Industrial Soil. Concentrations in some compounds were higher than the South Carolina Department of Health and Environmental Control background levels for nearby South Carolina, including aluminum, arsenic, barium, beryllium, chromium, copper, iron, lead, manganese, nickel, and potassium. A surface-water sample was collected from McCoys Creek and analyzed for volatile organic compounds, semivolatile organic compounds, and inorganic compounds (metals). No volatile organic compounds and (or) semivolatile organic compounds were detected at levels above the maximum contaminant level of the U.S. Environmental Protection Agency (USEPA) National Primary Drinking Water Standard, and no inorganic compounds exceeded the maximum contaminant level of the USEPA National Primary Drinking Water Standard or the Georgia In-Stream Water-Quality Standard. Iron was the only inorganic compound detected in the surface-water sample (578 micrograms per liter) that exceeded the USEPA National Secondary Drinking Water Standard of 300 micrograms per liter.

Concentration kinetics of secoisolariciresinol diglucoside and its biosynthetic precursor coniferin in developing flaxseed.

PubMed

Fang, Jingjing; Ramsay, Aina; Paetz, Christian; Tatsis, Evangelos C; Renouard, Sullivan; Hano, Christophe; Grand, Eric; Fliniaux, Ophélie; Roscher, Albrecht; Mesnard, Francois; Schneider, Bernd

2013-01-01

In the plant kingdom, flaxseed (Linum usitatissimum L.) is the richest source of secoisolariciresinol diglucoside (SDG), which is of great interest because of its potential health benefits for human beings. The information about the kinetics of SDG formation during flaxseed development is rare and incomplete. In this study, a reversed-phase high-performance liquid chromatography-diode array detection (HPLC-DAD) method was developed to quantify SDG and coniferin, a key biosynthetic precursor of SDG in flaxseed. Seeds from different developmental stages, which were scaled by days after flowering (DAF), were harvested. After alkaline hydrolysis, the validated HPLC method was applied to determine SDG and coniferin concentrations of flaxseed from different developing stages. Coniferin was found in the entire capsule as soon as flowering started and became undetectable 20 DAF. SDG was detected 6 DAF, and the concentration increased until maturity. On the other hand, the SDG amount in a single flaxseed approached the maximum around 25 DAF, before desiccation started. Concentration increase between 25 DAF and 35 DAF can be attributed to corresponding seed weight decrease. The biosynthesis of coniferin is not synchronous with that of SDG. Hence, the concentrations of SDG and coniferin change during flaxseed development. Copyright © 2012 John Wiley & Sons, Ltd.

Optimalisation of remote sensing algorithm in mapping of chlorophyl-a concentration at Pasuruan coastal based on surface reflectance images of Aqua Modis

NASA Astrophysics Data System (ADS)

Wibisana, H.; Zainab, S.; Dara K., A.

2018-01-01

Chlorophyll-a is one of the parameters used to detect the presence of fish populations, as well as one of the parameters to state the quality of a water. Research on chlorophyll concentrations has been extensively investigated as well as with chlorophyll-a mapping using remote sensing satellites. Mapping of chlorophyll concentration is used to obtain an optimal picture of the condition of waters that is often used as a fishing area by the fishermen. The role of remote sensing is a technological breakthrough in broadly monitoring the condition of waters. And in the process to get a complete picture of the aquatic conditions it would be used an algorithm that can provide an image of the concentration of chlorophyll at certain points scattered in the research area of capture fisheries. Remote sensing algorithms have been widely used by researchers to detect the presence of chlorophyll content, where the channels corresponding to the mapping of chlorophyll -concentrations from Landsat 8 images are canals 4, 3 and 2. With multiple channels from Landsat-8 satellite imagery used for chlorophyll detection, optimum algorithmic search can be formulated to obtain maximum results of chlorophyll-a concentration in the research area. From the calculation of remote sensing algorithm hence can be known the suitable algorithm for condition at coast of Pasuruan, where green channel give good enough correlation equal to R2 = 0,853 with algorithm for Chlorophyll-a (mg / m3) = 0,093 (R (-0) Red - 3,7049, from this result it can be concluded that there is a good correlation of the green channel that can illustrate the concentration of chlorophyll scattered along the coast of Pasuruan

Performance Analysis and Optimization of Concentrating Solar Thermoelectric Generator

NASA Astrophysics Data System (ADS)

Lamba, Ravita; Manikandan, S.; Kaushik, S. C.

2018-06-01

A thermodynamic model for a concentrating solar thermoelectric generator considering the Thomson effect combined with Fourier heat conduction, Peltier, and Joule heating has been developed and optimized in MATLAB environment. The temperatures at the hot and cold junctions of the thermoelectric generator were evaluated by solving the energy balance equations at both junctions. The effects of the solar concentration ratio, input electrical current, number of thermocouples, and electrical load resistance ratio on the power output and energy and exergy efficiencies of the system were studied. Optimization studies were carried out for the STEG system, and the optimum number of thermocouples, concentration ratio, and resistance ratio determined. The results showed that the optimum values of these parameters are different for conditions of maximum power output and maximum energy and exergy efficiency. The optimum values of the concentration ratio and load resistance ratio for maximum energy efficiency of 5.85% and maximum exergy efficiency of 6.29% were found to be 180 and 1.3, respectively, with corresponding power output of 4.213 W. Furthermore, at higher concentration ratio (C = 600), the optimum number of thermocouples was found to be 101 for maximum power output of 13.75 W, maximum energy efficiency of 5.73%, and maximum exergy efficiency of 6.16%. Moreover, the optimum number of thermocouple was the same for conditions of maximum power output and energy and exergy efficiency. The results of this study may provide insight for design of actual concentrated solar thermoelectric generator systems.

Ground-water levels and water-quality data for wells in the Spring Creek area near Arnold Air Force Base, Tennessee, April and May 2000

USGS Publications Warehouse

Williams, Shannon D.; Aycock, Robert A.

2001-01-01

Arnold Air Force Base (AAFB) occupies about 40,000 acres in Coffee and Franklin Counties, Tennessee. Numerous site-specific ground-water contamination investigations have been conducted at designated solid waste management units (SWMU?s) at AAFB. Several synthetic volatile organic compounds (VOC?s), primarily chlorinated solvents, have been identified in groundwater samples collected from monitoring wells near SWMU 8 in the Spring Creek area. During April and May 2000, a study of the groundwater resources in the Spring Creek area was conducted to determine if VOC?s from AAFB have affected local private water supplies and to advance understanding of the ground-water-flow system in this area. The study focused on sampling private wells located within the Spring Creek area that are used as a source of drinking water. Ground-water-flow directions were determined by measuring water levels in wells and constructing a potentiometric-surface map of the Manchester aquifer in the study area. Data were collected from a total of 35 private wells and 22 monitoring wells during the period of study. Depths to ground water were determined for 22 of the private wells and all 22 of the monitoring wells. The wells ranged in depth from 21 to 105 feet. Water-level altitudes ranged from 930 to 1,062 feet above sea level. Depths to water ranged from 8 to 83 feet below land surface. Water-quality samples were collected from 29 private wells which draw water from either gravel zones in the upper part of the Manchester aquifer, fractured bedrock in the lower part of the Manchester aquifer, or a combination of these two zones. Concentrations of 50 of the 55 VOC?s analyzed for were less than method detection limits. Chloroform, acetone, chloromethane, 2-butanone, and tetrachloroethylene were detected in concentrations exceeding the method detection limits. Only chloroform and acetone were detected in concentrations equal to or exceeding reporting limits. Chloroform was detected in a sample from one well at a concentration of 1.2 micrograms per liter (?g/L). Acetone was detected in a sample from another well at a concentration of 10 ?g/L. Acetone also was detected in a duplicate sample from the same well at an estimated concentration of 7.2 ?g/L, which is less than the reporting limit for acetone. The only contaminant of concern detected was tetrachloroethylene. Tetrachloroethylene was detected in only one sample, and this detection was at an estimated concentration below the reporting limit. None of the VOC concentrations exceeded drinking water maximum contaminant levels for public water systems.

Hydroxyapatite coatings containing Zn and Si on Ti-6Al-4Valloy by plasma electrolytic oxidation

NASA Astrophysics Data System (ADS)

Hwang, In-Jo; Choe, Han-Cheol

2018-02-01

In this study, hydroxyapatite coatings containing Zn and Si on Ti-6Al-4Valloy by plasma electrolytic oxidation were researched using various experimental instruments. The pore size is depended on the electrolyte concentration and the particle size and number of pore increase on surface part and pore part. In the case of Zn/Si sample, pore size was larger than that of Zn samples. The maximum size of pores decreased and minimum size of pores increased up to 10Zn/Si and Zn and Si affect the formation of pore shapes. As Zn ion concentration increases, the size of the particle tends to increase, the number of particles on the surface part is reduced, whereas the size of the particles and the number of particles on pore part increased. Zn is mainly detected at pore part, and Si is mainly detected at surface part. The crystallite size of anatase increased as the Zn ion concentration, whereas, in the case of Si ion added, crystallite size of anatase decreased.

Impedimetric method for measuring ultra-low E. coli concentrations in human urine.

PubMed

Settu, Kalpana; Chen, Ching-Jung; Liu, Jen-Tsai; Chen, Chien-Lung; Tsai, Jang-Zern

2015-04-15

In this study, we developed an interdigitated gold microelectrode-based impedance sensor to detect Escherichia coli (E. coli) in human urine samples for urinary tract infection (UTI) diagnosis. E. coli growth in human urine samples was successfully monitored during a 12-h culture, and the results showed that the maximum relative changes could be measured at 10Hz. An equivalent electrical circuit model was used for evaluating the variations in impedance characteristics of bacterial growth. The equivalent circuit analysis indicated that the change in impedance values at low frequencies was caused by double layer capacitance due to bacterial attachment and formation of biofilm on electrode surface in urine. A linear relationship between the impedance change and initial E. coli concentration was obtained with the coefficient of determination R(2)>0.90 at various growth times of 1, 3, 5, 7, 9 and 12h in urine. Thus our sensor is capable of detecting a wide range of E. coli concentration, 7×10(0) to 7×10(8) cells/ml, in urine samples with high sensitivity. Copyright © 2014 Elsevier B.V. All rights reserved.

Pyrethroids in chicken eggs from commercial farms and home production in Rio de Janeiro: Estimated daily intake and diastereomeric selectivity.

PubMed

Parente, Cláudio E T; Lestayo, Julliana; Guida, Yago S; Azevedo-Silva, Claudio E; Torres, João Paulo M; Meire, Rodrigo O; Malm, Olaf

2017-10-01

In this study, pyrethroids were determined in chicken eggs from commercial farm (n = 60) and home egg production (n = 30). These pyrethroids were investigated: bifenthrin, phenothrin, permethrin, cyfluthrin, cypermethrin and fenvalerate, including most diastereomers. Quantification was done using GC-MS in a negative chemical ionization mode. Pyrethroids residues were found in 79% of the analyzed samples. Cypermethrin presented the highest occurrence, being quantified in 62 samples (69%) in concentrations (lipid weight - l w.) varying between 0.29 and 6408 ng g -1 , followed by phenothrin (24%), 21-3910 ng g -1 , permethrin (14%), 2.96-328 ng g -1 , and bifenthrin (11%), 3.77-16.7 ng g -1 . Cyfluthrin and fenvalerate were not detected. Home-produced eggs had a higher occurrence of pyrethroids (97%), with a greater predominance of phenothrin. In commercial production, 70% of the samples presented pyrethroid residues (predominantly cypermethrin). This is the first report about the presence of pyrethroids in home-produced eggs and the first description of a selectivity pattern with the predominance of cis diastereomers in chicken eggs. In general, estimated daily intake does not present a risk to human consumption, according to Brazilian and international standards (FAO/WHO). However, one third of the samples (30 eggs) had concentrations above the maximum residue limits (MRLs). The maximum cypermethrin concentration was 66 times the MRL, while the maximum phenothrin concentration was 11 times the limit. Further studies about transfer dynamics, bioaccumulation and metabolic degradation of stereoisomers are required, as well as determining if this selectivity pattern in food can increase consumer's health risk. Copyright © 2017 Elsevier Ltd. All rights reserved.

Cabin air quality: indoor pollutants and climate during intercontinental flights with and without tobacco smoking.

PubMed

Lindgren, T; Norbäck, D

2002-12-01

The aim was to determine cabin air quality and in-flight exposure for cabin attendants of specific pollutants during intercontinental flights. Measurements of air humidity, temperature, carbon dioxide (CO2), respirable particles, ozone (O3), nitrogen dioxide (NO2) and formaldehyde were performed during 26 intercontinental flights with Boeing 767-300 with and without tobacco smoking onboard. The mean temperature in cabin was 22.2 degrees C (range 17.4-26.8 degrees C), and mean relative air humidity was 6% (range 1-27%). The CO2 concentration during cruises was below the recommended limit of 1000 ppm during 96% of measured time. Mean indoor concentration of NO2 and O3, were 14.1 and 19.2 micrograms/m3, with maximum values of 37 and 66 micrograms/m3, respectively. The concentration of formaldehyde was below the detection limit (< 5 micrograms/m3), in most samples (77%), and the maximum value was 15 micrograms/m3. The mean concentration of respirable particles in the rear part of the aircraft (AFT galley area) was much higher (49 micrograms/m3) during smoking as compared with non-smoking conditions (3 micrograms/m3) (P < 0.001), with maximum values of 253 and 7 micrograms/m3. In conclusion, air humidity is very low on intercontinental flights, and the large variation of temperature shows a need for better temperature control. Tobacco smoking onboard leads to a significant pollution of respirable particles, particularly in the rear part of the cabin. The result supports the view that despite the high air exchange rate and efficient air filtration, smoking in commercial aircraft leads to a significant pollution and should be prohibited.

[Output characteristics of rainfall runoff phosphorus pollution from a typical small watershed in Yimeng mountainous area].

PubMed

Yu, Xing-xiu; Li, Zhen-wei; Liu, Qian-jin; Jing, Guang-hua

2012-08-01

Relationships between phosphorus pollutant concentrations and precipitation-runoff were analyzed by monitoring pollutant losses at outlets of the Menglianggu watershed in 2010. A typical small watershed was selected to examine the runoff and quality parameters such as total phosphorus (TP), particle phosphorus (PP), dissolve phosphorus (DP) and dissolve inorganic phosphorus (DIP) in rainfall-runoff of 10 rainfall events. Precipitation was above 2 mm for all the 10 rainfall events. The results showed that the peak of phosphorus concentrations occurred before the peak of water flows, whereas change processes of the phosphorus fluxes were consistent with that of the water flows and the phosphorus flux also have a strong linear relationship with the water flows. The minimums of the phosphorus concentrations in every 10 natural rainfall events have small differences with each other, but the maximum and EMCs of the phosphorus concentrations have significant differences with each rainfall event. This was mainly influenced by the precipitation, maximum rainfall intensity and mean rainfall intensity (EMCs) and was less influenced by rainfall duration. DP and TP were mainly composed of DIP and PP, respectively. There were no significant correlations between DIP/DP dynamic changes and rainfall characteristics, whereas significant correlations between PP/TP dynamic changes and maximum rainfall intensity were detected. The production of DIP, DP, AND TP were mainly influenced by the direct runoff (DR) and base flow (BF). The EMCs of DIP, DP, TP and the variations of DIP/DP were all found to have significant polynomial relationships with DR/TR., but the dynamic changes of PP/ TP and the EMCS of PP were less influenced by the DR/TR.

Shallow ground-water quality in selected agricultural areas of south-central Georgia, 1994

USGS Publications Warehouse

Crandall, C.A.

1996-01-01

The Georgia-Florida Coastal Plain National Water-Quality Assessment Program began an agricultural land-use study in March 1994. The study area is located in the upper Suwannee River basin in Tift, Turner, Worth, Irwin, Wilcox, and Crisp Counties, Ga. Twenty-three shallow monitoring wells were installed in a 1,335-square- mile area characterized by intensive row-crop agriculture (peanuts, corn, cotton, and soybeans). The study focused on recently recharged shallow ground water in surficial aquifers to assess the relation between land-use activities and ground- water quality. All wells were sampled in March and April (spring) 1994, and 14 of these wells were resampled in August (summer) 1994. Shallow ground water in the study area is characterized by oxic and acidic conditions, low bicarbonate, and low dissolved-solids concentrations. The median pH of shallow ground water was 4.7 and the median bicarbonate concentration was 1.7 mg/L (milligrams per liter). Dissolved oxygen concentrations ranged from 3.0 to 8.0 mg/L. The median dissolved-solids concentration in samples collected in the spring was 86 mg/L. Major inorganic ion composition was generally mixed with no dominant cation; nitrate was the dominant anion (greater than 60 percent of the anion composition) in 14 of 23 samples. Only concentrations of bicarbonate, dissolved organic carbon, and nitrate had significant differences in concentrations between samples collected in the spring and the background samples. However, median concentrations of some of the major ingredients in fertilizer (including magnesium, chloride, nitrate, iron, and manganese) were higher in water samples from agricultural wells than in background samples. The median concentration of dissolved solids in ground-water samples collected in the spring (86 mg/L) was more than double the median concentration (41 mg/L) of the background samples. The median nitrate as nitrogen concentration of 6.7 mg/L in the spring samples reflects the effects of agricultural activities on ground-water quality. Samples from 30 percent of the wells exceeded the maximum contaminant level (MCL) for nitrate in drinking water (10 mg/L as N). Nitrogen isotope ratios ranged from 2.4 to 9.0 parts per thousand and indicate that most nitrogen in shallow ground water is probably from inorganic fertilizer. In addition, nitrate concentrations were positively correlated (p-values all less than 0.01) with concentrations of some of the major ingredients in fertilizer, such as potassium, calcium, magnesium, manganese, and chloride, and with values of specific conductance. Concentrations of pesticides and volatile organic compounds, detected in samples from 11 wells, were all below the MCLs. Of these constituents, only alachlor, metolachlor, metribuzin, toluene, benzene, and methyl chloride were detected in ground water at concentrations that ranged from 0.01 to 1.0 mg/L (micrograms per liter). Maximum concentrations of 1.0 mg/L of metolachlor and toluene were detected in two wells. Radon concentrations ranged from 530 to 1,400 pCi/L (picocuries per liter), exceeding the proposed MCL of 300 pCi/L in all samples; the median concentration was 1,000 pCi/L.

Detection of surface algal blooms using the newly developed algorithm surface algal bloom index (SABI)

NASA Astrophysics Data System (ADS)

Alawadi, Fahad

2010-10-01

Quantifying ocean colour properties has evolved over the past two decades from being able to merely detect their biological activity to the ability to estimate chlorophyll concentration using optical satellite sensors like MODIS and MERIS. The production of chlorophyll spatial distribution maps is a good indicator of plankton biomass (primary production) and is useful for the tracing of oceanographic currents, jets and blooms, including harmful algal blooms (HABs). Depending on the type of HABs involved and the environmental conditions, if their concentration rises above a critical threshold, it can impact the flora and fauna of the aquatic habitat through the introduction of the so called "red tide" phenomenon. The estimation of chlorophyll concentration is derived from quantifying the spectral relationship between the blue and the green bands reflected from the water column. This spectral relationship is employed in the standard ocean colour chlorophyll-a (Chlor-a) product, but is incapable of detecting certain macro-algal species that float near to or at the water surface in the form of dense filaments or mats. The ability to accurately identify algal formations that sometimes appear as oil spill look-alikes in satellite imagery, contributes towards the reduction of false-positive incidents arising from oil spill monitoring operations. Such algal formations that occur in relatively high concentrations may experience, as in land vegetation, what is known as the "red-edge" effect. This phenomena occurs at the highest reflectance slope between the maximum absorption in the red due to the surrounding ocean water and the maximum reflectance in the infra-red due to the photosynthetic pigments present in the surface algae. A new algorithm termed the surface algal bloom index (SABI), has been proposed to delineate the spatial distributions of floating micro-algal species like for example cyanobacteria or exposed inter-tidal vegetation like seagrass. This algorithm was specifically modelled to adapt to the marine habitat through its inclusion of ocean-colour sensitive bands in a four-band ratio-based relationship. The algorithm has demonstrated high stability against various environmental conditions like aerosol and sun glint.

Ammonia and methane emissions during drying of dewatered biogas digestate in a two-belt conveyor dryer.

PubMed

Awiszus, S; Meissner, K; Reyer, S; Müller, J

2018-01-01

Aim of the present study was to identify type and amount of emissions during the drying of biogas digestate in a two-belt conveyor dryer at different temperature settings and to investigate the effect on its nutrient content. Furthermore, the possibility of recovering nitrogen from the exhaust air was investigated. Emissions of CH 4 , CO 2 and NH 3 were measured by Fourier transform infrared spectroscopy. Biogas is mainly composed of CH 4 and CO 2 , hence gas release from the digestate during drying was expected to increase the concentration of these components. Although CO 2 concentration was elevated above the background concentration, CH 4 did not exceed the background concentration. Maximum NH 3 concentration of 183.3mg·m -3 was detected during drying. A NH 3 concentration of 10.8mg·m -3 was measured in the exhaust air of the ammonia scrubber, which is equal to a NH 3 reduction rate of 94%. Copyright © 2017 Elsevier Ltd. All rights reserved.

A novel freeze-dried storage and preparation method for the determination of mycophenolic acid in plasma by high-performance liquid chromatography.

PubMed

Wang, Lei; Qiang, Wei; Li, Ying; Cheng, Zeneng; Xie, Mengmeng

2017-09-01

Plasma samples were conventionally stored at freezing conditions until the time of detection. Such a technique, when carried out over an extended period, is energy consuming; in addition, preparation and transportation of stored samples is inconvenient. In this study, a freeze-dried storage and preparation method was proposed to determine the presence of mycophenolic acid (MPA) in plasma. Fresh plasma samples were freeze-dried using a device, and then stored at ambient temperature. After the stored samples were soaked with methanol spiked with the internal standard, high-performance liquid chromatography was conducted to detect MPA. The proposed method was demonstrated to be precise and accurate over the linear range of 0.5-50 μg mL -1 , with both intra- and inter-day precision being <7% and biases <10%. The freeze-dried samples were stable at ambient temperature for at least 40 days. This method was also successfully applied to the pharmacokinetic study of MPA in healthy volunteers. Pharmacokinetic parameters, such as maximum plasma concentration, time point of maximum plasma concentration and elimination half-life, among others, were consistent with the results in the published study. This proposed technique was proved to be simple, reproducible and energy saving. This approach could also simplify the storage and analysis of samples in clinical and scientific drug research. Copyright © 2017 John Wiley & Sons, Ltd.

Quantitative Exposure Assessment of Various Chemical Substances in a Wafer Fabrication Industry Facility

PubMed Central

Jang, Jae-Kil; Shin, Jung-Ah

2011-01-01

Objectives This study was designed to evaluate exposure levels of various chemicals used in wafer fabrication product lines in the semiconductor industry where work-related leukemia has occurred. Methods The research focused on 9 representative wafer fabrication bays among a total of 25 bays in a semiconductor product line. We monitored the chemical substances categorized as human carcinogens with respect to leukemia as well as harmful chemicals used in the bays and substances with hematologic and reproductive toxicities to evaluate the overall health effect for semiconductor industry workers. With respect to monitoring, active and passive sampling techniques were introduced. Eight-hour long-term and 15-minute short-term sampling was conducted for the area as well as on personal samples. Results The results of the measurements for each substance showed that benzene, toluene, xylene, n-butyl acetate, 2-methoxyethanol, 2-heptanone, ethylene glycol, sulfuric acid, and phosphoric acid were non-detectable (ND) in all samples. Arsine was either "ND" or it existed only in trace form in the bay air. The maximum exposure concentration of fluorides was approximately 0.17% of the Korea occupational exposure limits, with hydrofluoric acid at about 0.2%, hydrochloric acid 0.06%, nitric acid 0.05%, isopropyl alcohol 0.4%, and phosphine at about 2%. The maximum exposure concentration of propylene glycol monomethyl ether acetate (PGMEA) was 0.0870 ppm, representing only 0.1% or less than the American Industrial Hygiene Association recommended standard (100 ppm). Conclusion Benzene, a known human carcinogen for leukemia, and arsine, a hematologic toxin, were not detected in wafer fabrication sites in this study. Among reproductive toxic substances, n-butyl acetate was not detected, but fluorides and PGMEA existed in small amounts in the air. This investigation was focused on the air-borne chemical concentrations only in regular working conditions. Unconditional exposures during spills and/or maintenance tasks and by-product chemicals were not included. Supplementary studies might be required. PMID:22953186

A novel predictive pharmacokinetic/pharmacodynamic model of repolarization prolongation derived from the effects of terfenadine, cisapride and E-4031 in the conscious chronic av node--ablated, His bundle-paced dog.

PubMed

Nolan, Emily R; Feng, Meihua Rose; Koup, Jeffrey R; Liu, Jing; Turluck, Daniel; Zhang, Yiqun; Paulissen, Jerome B; Olivier, N Bari; Miller, Teresa; Bailie, Marc B

2006-01-01

Terfenadine, cisapride, and E-4031, three drugs that prolong ventricular repolarization, were selected to evaluate the sensitivity of the conscious chronic atrioventricular node--ablated, His bundle-paced Dog for defining drug induced cardiac repolarization prolongation. A novel predictive pharmacokinetic/pharmacodynamic model of repolarization prolongation was generated from these data. Three male beagle dogs underwent radiofrequency AV nodal ablation, and placement of a His bundle-pacing lead and programmable pacemaker under anesthesia. Each dog was restrained in a sling for a series of increasing dose infusions of each drug while maintained at a constant heart rate of 80 beats/min. RT interval, a surrogate for QT interval in His bundle-paced dogs, was recorded throughout the experiment. E-4031 induced a statistically significant RT prolongation at the highest three doses. Cisapride resulted in a dose-dependent increase in RT interval, which was statistically significant at the two highest doses. Terfenadine induced a dose-dependent RT interval prolongation with a statistically significant change occurring only at the highest dose. The relationship between drug concentration and RT interval change was described by a sigmoid E(max) model with an effect site. Maximum RT change (E(max)), free drug concentration at half of the maximum effect (EC(50)), and free drug concentration associated with a 10 ms RT prolongation (EC(10 ms)) were estimated. A linear correlation between EC(10 ms) and HERG IC(50) values was identified. The conscious dog with His bundle-pacing detects delayed cardiac repolarization related to I(Kr) inhibition, and detects repolarization change induced by drugs with activity at multiple ion channels. A clinically relevant sensitivity and a linear correlation with in vitro HERG data make the conscious His bundle-paced dog a valuable tool for detecting repolarization effect of new chemical entities.

Human and bovine viruses in the Milwaukee River Watershed: hydrologically relevant representation and relations with environmental variables

USGS Publications Warehouse

Corsi, Steven R.; Borchardt, M. A.; Spencer, S. K.; Hughes, Peter E.; Baldwin, Austin K.

2014-01-01

To examine the occurrence, hydrologic variability, and seasonal variability of human and bovine viruses in surface water, three stream locations were monitored in the Milwaukee River watershed in Wisconsin, USA, from February 2007 through June 2008. Monitoring sites included an urban subwatershed, a rural subwatershed, and the Milwaukee River at the mouth. To collect samples that characterize variability throughout changing hydrologic periods, a process control system was developed for unattended, large-volume (56–2800 L) filtration over extended durations. This system provided flow-weighted mean concentrations during runoff and extended (24-h) low-flow periods. Human viruses and bovine viruses were detected by real-time qPCR in 49% and 41% of samples (n = 63), respectively. All human viruses analyzed were detected at least once including adenovirus (40% of samples), GI norovirus (10%), enterovirus (8%), rotavirus (6%), GII norovirus (1.6%) and hepatitis A virus (1.6%). Three of seven bovine viruses analyzed were detected including bovine polyomavirus (32%), bovine rotavirus (19%), and bovine viral diarrhea virus type 1 (5%). Human viruses were present in 63% of runoff samples resulting from precipitation and snowmelt, and 20% of low-flow samples. Maximum human virus concentrations exceeded 300 genomic copies/L. Bovine viruses were present in 46% of runoff samples resulting from precipitation and snowmelt and 14% of low-flow samples. The maximum bovine virus concentration was 11 genomic copies/L. Statistical modeling indicated that stream flow, precipitation, and season explained the variability of human viruses in the watershed, and hydrologic condition (runoff event or low-flow) and season explained the variability of the sum of human and bovine viruses; however, no model was identified that could explain the variability of bovine viruses alone. Understanding the factors that affect virus fate and transport in rivers will aid watershed management for minimizing human exposure and disease transmission.

The Triple Roles of Glutathione for a DNA-Cleaving DNAzyme and Development of a Fluorescent Glutathione/Cu2+-Dependent DNAzyme Sensor for Detection of Cu2+ in Drinking Water.

PubMed

Wang, Shijin; Liu, Chengcheng; Li, Guiying; Sheng, Yongjie; Sun, Yanhong; Rui, Hongyue; Zhang, Jin; Xu, Jiacui; Jiang, Dazhi

2017-03-24

Pistol-like DNAzyme (PLDz) is an oxidative DNA-cleaving catalytic DNA with ascorbic acid as cofactor. Herein, glutathione was induced into the reaction system to maintain reduced ascorbic acid levels for higher efficient cleavage. However, data indicated that glutathione played triple roles in PLDz-catalyzed reactions. Glutathione alone had no effect on PLDz, and showed inhibitory effect on ascorbic acid-induced PLDz catalysis, but exhibited stimulating effect on Cu 2+ -promoted self-cleavage of PLDz. Further analysis of the effect of glutathione/Cu 2+ on PLDz indicated that H 2 O 2 played a key role in PLDz catalysis. Finally, we developed a fluorescent Cu 2+ sensor (PL-Cu 1.0) based on the relationship between glutathione/Cu 2+ and catalytic activity of PLDz. The fluorescent intensity showed a linear response toward the logarithm concentration of Cu 2+ over the range from 80 nM to 30 μM, with a detection limit of 21.1 nM. PL-Cu 1.0 provided only detection of Cu 2+ over other divalent metal ions. Ca 2+ and Mg 2+ could not interfere with Cu 2+ detection even at a 1000-fold concentration. We further applied PL-Cu 1.0 for Cu 2+ detection in tap and bottled water. Water stored in copper taps overnight had relatively high Cu 2+ concentrations, with a maximum 22.3 μM. Trace Cu 2+ (52.2 nM) in deep spring was detected among the tested bottled water. Therefore, PL-Cu 1.0 is feasible to detect Cu 2+ in drinking water, with a practical application.

Monitoring of perfluoroalkyl substances in the Ebro and Guadalquivir River basins (Spain)

NASA Astrophysics Data System (ADS)

Lorenzo, Maria; Campo, Julian; Andreu, Vicente; Pico, Yolanda; Farre, Marinella; Barcelo, Damia

2015-04-01

Relevant concentrations of a broad range of pollutants have been found in Spanish Mediterranean River basins, as consequence of anthropogenic pressures and overexploitation (Campo et al., 2014). In this study, the occurrence and sources of 21 perfluoroalkyl substances (PFASs) were determined in water and sediment of the Ebro and Guadalquivir River basins (Spain). PFASs are persistent, bio-accumulative and toxic, which make them a hazard to human health and wildlife. The Ebro and Guadalquivir Rivers are the two most important rivers of Spain. They are representative examples of Mediterranean rivers heavily managed, and previous researches have reported their high pesticide contamination (Masiá et al., 2013). Analytes were extracted by solid phase extraction (SPE) and determined by liquid chromatography coupled to tandem mass spectrometry (LC/MS-MS). In water samples, from 21 analytes screened, 11 were found in Ebro samples and 9 in Guadalquivir ones. In both basins, the most frequents were PFBA, PFPeA, PFHxS and PFOS. Maximum concentration was detected for PFBA, with 251.3 ng L-1 in Ebro and 742.9 ng L-1 in Guadalquivir. Regarding the sediment samples, 8 PFASs were detected in those coming from Ebro basin and 9 in those from Guadalquivir. The PFASs most frequently detected were PFBA, PFPeA, PFOS and PFBS. Maximum concentration in Ebro samples was detected for PFOA, with 32.4 ng g-1 dw, and in Guadalquivir samples for PFBA with 63.8 ng g-1 dw. Ubiquity of these compounds in the environment was proved with high PFAS concentration values detected in upper parts of the rivers. Results confirm that most of the PFASs are only partially eliminated during the secondary treatment suggesting that they can be a focal point of contamination to the rivers where they can bio-accumulate and produce adverse effects on wildlife and humans. Acknowledgment The Spanish Ministry of Economy and Competitiveness has supported this work through the projects SCARCE-CSD2009-00065, CGL2011-29703-C02-01 and CGL2011-29703-C02-02 References Campo, J., Pérez, F., Masiá, A., Picó, Y., Farré, M., Barceló, D., 2014. Perfluoroalkyl substance contamination of the Llobregat River ecosystem (Mediterranean area, NE Spain). Science of the Total Environment DOI: 10.1016/j.scitotenv.2014.05.094. Masiá, A., Campo J., Vázquez-Roig, P., Blasco, C., Picó Y., 2013. Screening of currently used pesticides in water, sediments and biota of the Guadalquivir River Basin (Spain). J. Hazard. Mater. 263P, 95-104.

Groundwater quality in the Lake Champlain Basin, New York, 2009

USGS Publications Warehouse

Nystrom, Elizabeth A.

2011-01-01

Water was sampled from 20 production and domestic wells from August through November 2009 to characterize groundwater quality in the Lake Champlain Basin in New York. Of the 20 wells sampled, 8 were completed in sand and gravel, and 12 were completed in bedrock. The samples were collected and processed by standard U.S. Geological Survey procedures and were analyzed for 147 physiochemical properties and constituents, including major ions, nutrients, trace elements, pesticides, volatile organic compounds (VOCs), radionuclides, and indicator bacteria. Water quality in the study area is generally good, but concentrations of some constituents equaled or exceeded current or proposed Federal or New York State drinking-water standards; these were color (1 sample), pH (3 samples), sodium (3 samples), total dissolved solids (4 samples), iron (4 samples), manganese (3 samples), gross alpha radioactivity (1 sample), radon-222 (10 samples), and bacteria (5 samples). The pH of all samples was typically neutral or slightly basic (median 7.1); the median water temperature was 9.7°C. The ions with the highest median concentrations were bicarbonate [median 158 milligrams per liter (mg/L)] and calcium (median 45.5 mg/L). Groundwater in the study area is soft to very hard, but more samples were hard or very hard (121 mg/L or more as CaCO3) than were moderately hard or soft (120 mg/L or less as CaCO3); the median hardness was 180 mg/L as CaCO3. The maximum concentration of nitrate plus nitrite was 3.79 mg/L as nitrogen, which did not exceed established drinking-water standards for nitrate plus nitrite (10 mg/L as nitrogen). The trace elements with the highest median concentrations were strontium (median 202 micrograms per liter [μg/L]), and iron (median 55 μg/L in unfiltered water). Six pesticides and pesticide degradates, including atrazine, fipronil, disulfoton, prometon, and two pesticide degradates, CIAT and desulfinylfipronil, were detected among five samples at concentrations of 0.02 μg/L or less; they included herbicides, herbicide degradates, insecticides, and insecticide degradates. Six VOCs were detected among six samples; these included a solvent, the gasoline additive methyl tert-butyl ether (MTBE), and four trihalomethanes. The highest radon-222 activities were in samples from crystalline bedrock wells (maximum 4,100 picocuries per liter [pCi/L]); half of all samples exceeded a proposed U.S. Environmental Protection Agency (USEPA) drinking-water standard of 300 pCi/L. Total coliform bacteria were detected in five samples, fecal coliform bacteria were detected in one sample, and Escherichia coli (E. coli) were not detected in any sample.

Nanoplasmonic biochips for rapid label-free detection of imidacloprid pesticides with a smartphone.

PubMed

Lee, Kuang-Li; You, Meng-Lin; Tsai, Chia-Hsin; Lin, En-Hung; Hsieh, Shu-Yi; Ho, Ming-Hsun; Hsu, Ju-Chun; Wei, Pei-Kuen

2016-01-15

The widespread and intensive use of neonicotinoid insecticides induces negative cascading effects on ecosystems. It is desirable to develop a portable sensitive sensing platform for on-site screening of high-risk pesticides. We combined an indirect competitive immunoassay, highly sensitive surface plasmon resonance (SPR) biochip and a simple portable imaging setup for label-free detection of imidacloprid pesticides. The SPR biochip consists of several capped nanoslit arrays with different periods which form a spectral image on the chip. The qualitative and semiquantitative analyses of pesticides can be directly observed from the spot shift on the chip. The precise semiquantitative analyses can be further completed by using image processing in a smartphone. We demonstrate simultaneous detection of four different concentrations of imidacloprid pesticides. The visual detection limit is about 1ppb, which is well below the maximum residue concentration permitted by law (20ppb). Compared to the one-step strip assay, the proposed chip is capable of performing semiquantitative analyses and multiple detection. Compared to the enzyme-linked immunosorbent assay, our method is label-free and requires simple washing steps and short reaction time. In addition, the label-free chip has a comparable sensitivity but wider working range than those labeling techniques. Copyright © 2015 Elsevier B.V. All rights reserved.

The Assessment of Liver Reserve Function by Spectrophotometry based on Determination of Phenacetin and Paracetamol.

PubMed

Ren, Rui; Ma, Yongmei; Ma, Wanshan; Lu, Sumei

2015-01-01

To establish a technical system for assessing liver reserve function based on spectrophotometry by detection of phenacetin and paracetamol in blood samples. Taking detected contents of phenacetin and paracetamol by high performance liquid chromatography (HPLC) as standard, which was proved to be able to detect drug concentrations with high resolution and accuracy, we established a technical system based on the spectrophotometric technique to assay phenacetin and paracetamol, including the color system, the maximum absorption wavelength, the influence factors of color system, and the optimal conditions for hydrolysis. Then we verified our established system compared with that under HPLC by recovery test. This study established a technical system to detect phenacetin and paracetamol in blood samples using spectrophotometry. Mainly, 3 mol/L hydrochloric acid (HCl) was added to samples for hydrolysis for 30 minutes, then, adding 0.02% 1,2-naphthoquinone-4-sulfonate (NQS), 1% cetyltrimethyl ammonium bromide (CTA) and 2% sodium hydroxide (or 3% sodium carbonate) (ratio of 1:6:1:2 or 3), and the absorbance was measured at 500 nm and 570 nm to calculate their concentrations. Using an established spectrophotometric system to detect phenacetin and paracetamol in blood samples could assess liver reserve function, which was proved comparable with HPLC in resolution and repeatability.

Optical Detection of Formaldehyde

NASA Technical Reports Server (NTRS)

Patty, Kira D.; Gregory, Don A.

2008-01-01

The potential for buildup .of formaldehyde in closed space environments poses a direct health hazard to personnel. The National Aeronautic Space Agency (NASA) has established a maximum permitted concentration of 0.04 ppm for 7 to 180 days for all space craft. Early detection is critical to ensure that formaldehyde levels do not accumulate. above these limits. New sensor technologies are needed to enable real time,in situ detection in a compact and reusable form factor. Addressing this need,research into the use of reactive fluorescent dyes which reversibly bind to formaldehyde (liquid or gas) has been conducted to support the development of a formaldehyde.sensor. In the presence of formaldehyde the dyes' characteristic fluorescence peaks shift providing the basis for an optical detection. Dye responses to formaldehyde exposure were characterized; demonstrating the optical detection of formaldehyde in under 10 seconds and down to concentrations of 0.5 ppm. To .incorporate the dye .in.an optical sensor device requires. a means of containing and manipulating the dye. Multiple form factors using two dissimilar sbstrates were considered to determine a suitable configuration. A prototype sensor was demonstrated and considerations for a field able sensor were presented. This research provides a necessary first step toward the development of a compact, reusable; real time optical formaldehyde sensor suitable for use in the U.S. space program,

Preliminary investigation on the occurrence of several sulfonamide antibiotics in the Haihe River Basin of China

NASA Astrophysics Data System (ADS)

Zhang, S. L.; Zhang, J.; Wang, Z. G.; Wang, Y. Z.; Liang, S. T.; Liu, C.; Wang, Z.

2017-08-01

Several samples collected from lakes, rivers and reservoirs in Haihe river basin of China were analyzed for 8 sulfonamide antibiotics by using solid-phase extraction and liquid chromatography with tandem mass spectrometry (HPLC-MS/MS). All water samples were enriched with HLB extraction cartridges. The antibiotics were separated by gradient elution with methanol as the mobile phase adding 0.1% formic acid. The eluate was then analyzed by the mode of multiple reaction monitoring (MRM). The limits of detection (LOD) and quantification (LOQ) were 0.4-1.0 ng/L and 1.0-3.0 ng/L respectively. The method was used for the analysis of 13 samples from Haihe river basin in China. The results showed that sulfamethoxazole was present in all water samples with maximum concentration of 107.59 ng/L. Sulfadiazine was also frequently detected, concentrations ranging from 2.81 ng/L to 85.35 ng/L. Other sulfonamide antibiotics were not detected in most water samples, especially for those samples from drinking water resources.

Electrochemical pesticide detection with AutoDip--a portable platform for automation of crude sample analyses.

PubMed

Drechsel, Lisa; Schulz, Martin; von Stetten, Felix; Moldovan, Carmen; Zengerle, Roland; Paust, Nils

2015-02-07

Lab-on-a-chip devices hold promise for automation of complex workflows from sample to answer with minimal consumption of reagents in portable devices. However, complex, inhomogeneous samples as they occur in environmental or food analysis may block microchannels and thus often cause malfunction of the system. Here we present the novel AutoDip platform which is based on the movement of a solid phase through the reagents and sample instead of transporting a sequence of reagents through a fixed solid phase. A ball-pen mechanism operated by an external actuator automates unit operations such as incubation and washing by consecutively dipping the solid phase into the corresponding liquids. The platform is applied to electrochemical detection of organophosphorus pesticides in real food samples using an acetylcholinesterase (AChE) biosensor. Minimal sample preparation and an integrated reagent pre-storage module hold promise for easy handling of the assay. Detection of the pesticide chlorpyrifos-oxon (CPO) spiked into apple samples at concentrations of 10(-7) M has been demonstrated. This concentration is below the maximum residue level for chlorpyrifos in apples defined by the European Commission.

Detection of cadmium ion in water using films of nanocomposite of functionalized carbon nanotubes and anionic polymer

NASA Astrophysics Data System (ADS)

Taneja, Parul; Manjuladevi, V.; Gupta, R. K.

2018-05-01

Presence of cadmium in drinking water is one of the major threats to human health. According to international standards, the maximum permission concentration of cadmium ion in drinking water should be less than 0.002 to 0.010mg/l (2-10 ppb). It is one of the major contaminants in potable water in western part of Indian subcontinent. It is found up to 2.3 to 8.6 mg/l in Rajasthan water. In this article, we report our study on detection of cadmium ion in water employing a sensing layer of nanocomposites of functionalized single walled carbon nanotubes (SWCNTs) and polyacrylic acid (PAA). The film was deposited onto 5 MHz AT-cut quartz crystal of a quartz crystal microbalance (QCM). The response was collected in both static and dynamic mode. We obtained a linear response curve in a given concentration range of cadmium ion indicating the suitability of the functional layer for cadmium ion detection in water. The surface morphology of the functional layer was studied using atomic force microscope before and after sensing.

Organochlorine insecticide residues are found in surface, irrigated water samples from several districts in Bangladesh.

PubMed

Chowdhury, Alamgir Zaman; Islam, Mohammad Nazrul; Moniruzzaman, Mohammed; Gan, Siew Hua; Alam, Md Khorshed

2013-02-01

The purpose of this study was to investigate the occurrence and distribution of organochlorines such as aldrin, dieldrin, dichlorodiphenyldichloroethylene (DDE), dichlorodiphenyldichloroethane (DDD), dichlorodiphenyltrichloroethane (DDT), endrin, lindane and heptachlor insecticide residues in irrigated surface water samples collected from 22 districts in Bangladesh. The concentrations of the pesticides were determined using gas chromatography mass spectrophotometry. Water samples from five locations (Feni, Nawabganj, Putia, Burichang and Chatak) were contaminated with DDT; the highest DDT concentration detected was 8.29 μg/L, and its metabolite, DDE, was detected at 4.06 μg/L. Water samples from four other locations (Natore, Sikderpara, Chatak and Rajoir) were contaminated with heptachlor residues, and the highest level detected was 5.24 μg/L, which is the above the maximum contaminant level recommended by the World Health Organisation. A water sample collected from Chatak, Sunamganj, was contaminated with both DDT and heptachlor pesticide residues. None of the water samples were contaminated with aldrin, DDD, dieldrin, endrin or lindane. It is concluded that continuous, long-term monitoring and essential steps to limit the use of the pesticides in Bangladesh are needed.

Quality of shallow ground water in alluvial aquifers of the Willamette Basin, Oregon, 1993-95

USGS Publications Warehouse

Hinkle, Stephen R.

1997-01-01

The current (1993?95) quality of shallow ground water (generally, <25 meters below land surface) in Willamette Basin alluvium is described using results from two studies. A Study-Unit Survey, or regional assessment of shallow groundwater quality in alluvium, was done from June through August 1993. During the Study-Unit Survey, data were collected from 70 domestic wells chosen using a random-selection process and located mostly in areas of agricultural land use. An urban Land-Use Study, which was a reconnaissance of shallow urban ground-water quality from 10 monitoring wells installed in areas of residential land use, was done in July 1995. Concentrations of nitrite plus nitrate (henceforth, nitrate, because nitrite concentrations were low) ranged from <0.05 to 26 mg N/L (milligrams nitrogen per liter) in ground water from 70 Study-Unit-Survey wells; concentrations exceeded the U.S. Environmental Protection Agency (USEPA) Maximum Contaminant Level (MCL) of 10 mg N/L in 9 percent of Study-Unit-Survey samples. Relationships were observed between nitrate concentrations and dissolved-oxygen concentrations, the amount of clay present within and overlying aquifers, overlying geology, and upgradient land use. Tritium (3H) data indicate that 21 percent of Study-Unit-Survey samples represented water recharged prior to 1953. Nitrogen-fertilizer application rates in the basin have increased greatly over the past several decades. Thus, some observed nitrate concentrations may reflect nitrogen loading rates that were smaller than those presently applied in the basin. Concentrations of phosphorus ranged from <0.01 to 2.2 mg/L in 70 Study-Unit-Survey wells and exceeded 0.10 mg/L in 60 percent of the samples. Phosphorus and nitrate concentrations were inversely correlated. From 1 to 5 pesticides and pesticide degradation products (henceforth, pesticides) were detected in ground water from each of 23 Study-Unit-Survey wells (33 percent of 69 wells sampled for pesticides) for a total of 51 pesticide detections. Thirteen different pesticides were detected; atrazine was the most frequently encountered pesticide. Although detections were widespread, concentrations were low (generally <1,000 ng/L [nanograms per liter]). (One ng/L is equal to 0.001 mg/L [micrograms per liter].) One detection (dinoseb, at 7,900 ng/L) exceeded a USEPA MCL. Relationships were observed between the occurrence of pesticides and the amount of clay present within and overlying aquifers, overlying geology, and land use. Between 1 and 5 volatile organic compounds (VOCs) were detected at each of 7 Study-Unit-Survey sites (11 percent of 65 sites evaluated), for a total of 14 VOC detections. One detection (tetrachloroethylene, at 29 mg/L) exceeded a USEPA MCL. Other detections were at low concentrations (0.2 to 2.0 mg/L). VOC detections generally were from sites associated with urban land use. Concentrations of arsenic ranged from <1 to 13 mg/L in 70 Study-Unit-Survey wells. Concentrations in 16 percent of samples exceeded the USEPA Risk-Specific-Dose Health Advisory of 2 mg/L. Radon concentrations ranged from 200 to 1,200 pCi/L (picocuries per liter) in 51 Study-Unit-Survey wells. All samples exceeded the USEPA Risk-Specific-Dose Health Advisory of 150 pCi/L. All urban Land-Use-Study samples were well oxygenated; thus, nitrate reduction probably did not affect these samples. Urban Land-Use-Study nitrate concentrations were similar to those of the well oxygenated, agricultural subset of Study-Unit-Survey samples. Pesticides were detected in samples from three urban Land-Use-Study sites, but concentrations were low (1 to 5 ng/L). In contrast, VOCs were detected in ground water from 80 percent of urban Land-Use-Study wells; concentrations ranged up to 7.6 mg/L. Trace-element concentrations in the urban Land-Use Study samples were low. Median concentrations consistently were <10 mg/L and frequently were <1 mg/L

Water quality of the Flint River basin, Alabama and Tennessee, 1999-2000

USGS Publications Warehouse

Hoos, Anne B.; Garrett, Jerry W.; Knight, Rodney R.

2002-01-01

The U.S. Geological Survey monitored eight stream sites in the Flint River Basin during the period January 1999 through May 2000, to characterize patterns in the occurrence of pesticides, fecal-indicator bacteria, and nutrients in relation to season and streamflow conditions and to land-use patterns. This study is part of the National Water-Quality Assessment Program, which was designed to assess water quality as it relates to various land uses. Every water sample collected from the Flint River Basin had detectable levels of at least two pesticides; 64 percent of the samples contained mixtures of at least five pesticides. In general, pesticides detected most frequently and at highest concentrations in streams corresponded to the pesticides with the highest rates of use in the watersheds. Detections of fluometuron, norflurazon, and atrazine were more frequent (by a margin of 15 percent or more) in samples from the Flint River when compared with the frequencies of pesticide detections at 62 agricultural stream sites across the Nation. Detections of fluometuron in the Flint River were more frequent even when compared with a cotton-cultivation subset of the 62 sites. For most pesticides, maximum concentrations did not exceed criteria to protect aquatic life; however, maximum concentrations of atrazine, cyanazine, and malathion exceeded aquaticlife criteria in at least one sample. Concentrations near or exceeding the aquatic-life criteria occurred only during the spring and summer (April-July), and generally occurred during storm flows. Less than 5 percent of the estimated mass of pesticides applied annually to agricultural areas in the Flint River Basin was transported to the stream at the monitoring points on the Flint River near Brownsboro, Alabama, and on Hester Creek near Plevna, Alabama. The pesticides with the highest ratios (greater than 3 percent) of the amount transported instream to the amount applied?atrazine, metolachlor, fluometuron, and norflurazon?are preemergent herbicides applied to the soil before the crops have emerged, which increases the probability of transport in surface runoff. Concentrations of the fecal-bacteria indicator Escherichia coli (E. coli) in the Flint River and Hester Creek exceeded the U.S. Environmental Protection Agency criterion for recreation in almost all storm samples, and in many samples collected up to 6 days following a storm. Concentrations in the Flint River were strongly correlated with sample turbidity, suggesting that turbidity might be useful as a surrogate for estimating E. coli concentrations. Concentrations of the nutrients nitrogen and phosphorus in samples from the Flint River generally exceeded thresholds indicating eutrophic potential, whereas concentrations in samples from Hester Creek were generally below the thresholds. When compared with nutrient data from a set of 24 agricultural basins across the southeastern region of the United States, concentrations in the Flint River and Hester Creek were slightly above the regional median. Base-flow concentrations of certain pesticides, nutrients, and E. coli were compared to land-use information for eight sites in the Flint River Basin. The highest base-flow concentrations of aldicarb sulfoxide, fluometuron, and phosphorus were found in the tributaries with the greatest density of cotton acreage in the watershed. Similarly, high base-flow concentrations of total nitrogen were correlated with a high percentage of cultivated land in the watershed. Lack of information about distribution of stream access by livestock weakened the analysis of correlation between livestock and base-flow concentrations of E. coli and nutrients. Input of dissolved and suspended chemicals from the Flint River during storms influences water quality in the reach of the Tennessee River from which the City of Huntsville, Alabama, withdraws about 40 percent of its drinking water. During the storm of April 2-5, 2000, concentrations of several pesticides were

Enzyme activity and expression pattern of intra- and extracellular chitinase and β-1,3-glucanase of Wickerhamomyces anomalus EG2 using glycol chitin and glucan-containing high polymer complex.

PubMed

Hong, Sin-Hyoung; Song, Yong-Su; Seo, Dong-Jun; Kim, Kil-Yong; Jung, Woo-Jin

2017-12-01

We investigated cell growth and activity of intra- and extracellular chitinase, β-1,3-glucanase, and chitin deacetylase with SDS-PAGE by incubating W. anomalus EG2 in PDB and YPD media for 24h in presence of different concentrations (0%, 0.1%, 0.3%, and 0.5%) of colloidal chitin. Maximum cell growth was observed in both PDB and YPD media without colloidal chitin. In the absence of colloidal chitin, maximum extracellular β-1,3-glucanase activity of 32.96 and 47.28 units/mL was reported at 18h in PDB medium and 6h in YPD medium, respectively. In addition, extracellular chitinase was unaffected by various concentrations of carboxymethyl chitin in both PDB and YPD media. In the absence of colloidal chitin, maximum intracellular chitinase activity was indicated to be 9.82 and 9.86 units/mg protein in PDB and YPD media, respectively. Maximum intracellular β-1,3-glucanase activity reported was 17.34 units/mg protein in PDB medium containing 0.5% colloidal chitin and 15.0 units/mg protein in YPD medium containing 0.3% colloidal chitin. Five major isozymes, GN1, GN2, GN3, GN4, and GN5, of intracellular β-1,3-glucanase were detected with glucan-containing high polymer complex as a substrate with or without colloidal chitin. Copyright © 2017 Elsevier B.V. All rights reserved.

Enumerating Sparse Organisms in Ships’ Ballast Water: Why Counting to 10 Is Not So Easy

PubMed Central

2011-01-01

To reduce ballast water-borne aquatic invasions worldwide, the International Maritime Organization and United States Coast Guard have each proposed discharge standards specifying maximum concentrations of living biota that may be released in ships’ ballast water (BW), but these regulations still lack guidance for standardized type approval and compliance testing of treatment systems. Verifying whether BW meets a discharge standard poses significant challenges. Properly treated BW will contain extremely sparse numbers of live organisms, and robust estimates of rare events require extensive sampling efforts. A balance of analytical rigor and practicality is essential to determine the volume of BW that can be reasonably sampled and processed, yet yield accurate live counts. We applied statistical modeling to a range of sample volumes, plankton concentrations, and regulatory scenarios (i.e., levels of type I and type II errors), and calculated the statistical power of each combination to detect noncompliant discharge concentrations. The model expressly addresses the roles of sampling error, BW volume, and burden of proof on the detection of noncompliant discharges in order to establish a rigorous lower limit of sampling volume. The potential effects of recovery errors (i.e., incomplete recovery and detection of live biota) in relation to sample volume are also discussed. PMID:21434685

Water quality in shallow alluvial aquifers, Upper Colorado River Basin, Colorado, 1997

USGS Publications Warehouse

Apodaca, L.E.; Bails, J.B.; Smith, C.M.

2002-01-01

Shallow ground water in areas of increasing urban development within the Upper Colorado River Basin was sampled for inorganic and organic constituents to characterize water-quality conditions and to identify potential anthropogenic effects resulting from development. In 1997, 25 shallow monitoring wells were installed and sampled in five areas of urban development in Eagle, Grand, Gunnison, and Summit Counties, Colorado. The results of this study indicate that the shallow ground water in the study area is suitable for most uses. Nonparametric statistical methods showed that constituents and parameters measured in the shallow wells were often significantly different between the five developing urban areas. Radon concentrations exceeded the proposed USEPA maximum contaminant level at all sites. The presence of nutrients, pesticides, and volatile organic compounds indicate anthropogenic activities are affecting the shallow ground-water quality in the study area. Nitrate as N concentrations greater than 2.0 mg/L were observed in ground water recharged between the 1980s and 1990s. Low concentrations of methylene blue active substances were detected at a few sites. Total coliform bacteria were detected at ten sites; however, E. coli was not detected. Continued monitoring is needed to assess the effects of increasing urban development on the shallow ground-water quality in the study area.

Comparison of supercritical fluid extraction and Soxhlet extraction for the determination of PCBs in seaweed samples.

PubMed

Punín Crespo, M O; Lage Yusty, M A

2005-06-01

The efficiency of supercritical fluid extraction for the determination of 12 polychlorinated biphenyls from algae samples is compared to Soxhlet extraction. Analytical detection limits for the individual congeners ranged from 0.62 microgl(-1) to 19 microgl(-1). Recovery was tested for both methods using standard addition procedure. At maximum spike level of concentration, the mean recoveries were not significantly different (P>0.05) of all PCBs studied, with the exception of PCBs 28, 52, 77 and 169. Method precision for Soxhlet extraction (< or =3.9%) was slightly better than for SFE (< or =9.2%). Although both methods yield comparable results, SFE offers the advantage of detecting all PCBs studied at lower concentrations, reducing extraction time, and reducing the amount of solvents needed. The optimized methods were applied to the analysis of three real seaweed samples, except for PCB101 the concentrations of all PCBs were low or below the detection limits. The levels of PCB101 found in sample 1 were 6.6+/-0.54 ng g(-1) d.w., in sample 2 the levels were 8.2+/-0.86 ng g(-1) d.w. and in sample 3 they were 7.7+/-0.08 ng g(-1) d.w.

Enumerating sparse organisms in ships' ballast water: why counting to 10 is not so easy.

PubMed

Miller, A Whitman; Frazier, Melanie; Smith, George E; Perry, Elgin S; Ruiz, Gregory M; Tamburri, Mario N

2011-04-15

To reduce ballast water-borne aquatic invasions worldwide, the International Maritime Organization and United States Coast Guard have each proposed discharge standards specifying maximum concentrations of living biota that may be released in ships' ballast water (BW), but these regulations still lack guidance for standardized type approval and compliance testing of treatment systems. Verifying whether BW meets a discharge standard poses significant challenges. Properly treated BW will contain extremely sparse numbers of live organisms, and robust estimates of rare events require extensive sampling efforts. A balance of analytical rigor and practicality is essential to determine the volume of BW that can be reasonably sampled and processed, yet yield accurate live counts. We applied statistical modeling to a range of sample volumes, plankton concentrations, and regulatory scenarios (i.e., levels of type I and type II errors), and calculated the statistical power of each combination to detect noncompliant discharge concentrations. The model expressly addresses the roles of sampling error, BW volume, and burden of proof on the detection of noncompliant discharges in order to establish a rigorous lower limit of sampling volume. The potential effects of recovery errors (i.e., incomplete recovery and detection of live biota) in relation to sample volume are also discussed.

Detection of aflatoxin M1 in powdered milk and sweetened condensed milk products in several cities in Java with HPLC-fluorescence method

NASA Astrophysics Data System (ADS)

Wijaya, H.; Wardayanie, N. I.; Widjajanti, R.; Silitonga, R. F.

2018-01-01

Aflatoxin M1 (AFM1) is a hydroxylated metabolite of aflatoxin B1 (AFB1) produced by lactating animals due to consuming AFB1-contaminated feed. AFM1 can be found in dairy products because it is resistant to heat during processing. This study aimed to detect AFM1 in powdered milk and sweetened condensed milk sold in several cities in Java. The amount of powdered milk sample was 20, while the amount of sweetened condensed milk sample was 16. AFM1 detection in powdered milk and sweetened condensed milk was conducted by HPLC-fluorescence method. The results showed that the concentration of AFM1 in powdered milk ranged from undetectable to 0.549 μg/kg and the highest data (55%) was distributed in concentration range of >0.05 μg/kg - 0.2 μg/kg. On the other hand, AFM1 levels in sweetened condensed milk ranged from undetectable to 0.056 μg/kg and 43.75% data was distributed in concentration range of >0.025 μg/kg - 0.05 μg/kg. All powdered milk and sweetened condensed milk samples have met the maximum level of AFM1 according to Indonesian regulation.

Determination of quinolones and fluoroquinolones, tetracyclines and sulfonamides in bovine, swine and poultry liver using LC-MS/MS.

PubMed

Martins, Magda Targa; Barreto, Fabiano; Hoff, Rodrigo Barcelos; Jank, Louise; Arsand, Juliana Bazzan; Feijó, Tiago Correa; Schapoval, Elfrides Eva Scherman

2015-01-01

Antibacterials are widely used in veterinary medicine. Residues of these drugs can remain in food of animal origin, including bovine liver. This paper describes a fast and simple analytical method for the determination of quinolones and fluoroquinolones, tetracyclines and sulfonamides in bovine liver samples. Deuterated enrofloxacin, sulfapyridine and demeclocycline were used as internal standards. The homogenised liver samples were extracted with acidified acetonitrile. Steps of non-solid-phase extraction (SPE) clean-up and concentration were used in the presented method. The final extracts were analysed by sensitive and selective detection of all components in a single run using LC-MS/MS. Acceptable recoveries between 66% and 110% were obtained. Good linearity (r(2)) above 0.96, considering three different days, for all drugs was achieved in concentrations ranging from 0.0 to 2.0 × the maximum residue limit (MRL). Intraday precision with coefficient of variation (CV%) (n = 6) lower than 14.7% and inter-day precision lower than 18.8% in agreement with European Commission Decision 2002/657/EC were obtained in concentrations ranging from 0.5 to 1.5 MRL. Accuracy was between 86% and 110%. Limits of detection and quantitation, as well as decision limit (CCα) and detection capability (CCβ), were also evaluated.

Qualification of a Multi-Channel Infrared Laser Absorption Spectrometer for Monitoring CO, HCl, HCN, HF, and CO2 Aboard Manned Spacecraft

NASA Technical Reports Server (NTRS)

Briggs, Ryan M.; Frez, Clifford; Forouhar, Siamak; May, Randy D.; Meyer, Marit E.; Kulis, Michael J.; Berger, Gordon M.

2015-01-01

Monitoring of specific combustion products can provide early-warning detection of accidental fires aboard manned spacecraft and also identify the source and severity of combustion events. Furthermore, quantitative in situ measurements are important for gauging levels of exposure to hazardous gases, particularly on long-duration missions where analysis of returned samples becomes impractical. Absorption spectroscopy using tunable laser sources in the 2 to 5 micrometer wavelength range enables accurate, unambiguous detection of CO, HCl, HCN, HF, and CO2, which are produced in varying amounts through the heating of electrical components and packaging materials commonly used aboard spacecraft. Here, we report on calibration and testing of a five-channel laser absorption spectrometer designed to accurately monitor ambient gas-phase concentrations of these five compounds, with low-level detection limits based on the Spacecraft Maximum Allowable Concentrations. The instrument employs a two-pass absorption cell with a total optical pathlength of 50 cm and a dedicated infrared semiconductor laser source for each target gas. We present results from testing the five-channel sensor in the presence of trace concentrations of the target compounds that were introduced using both gas sources and oxidative pyrolysis (non-flaming combustion) of solid material mixtures.

Multiresidue determination of fluoroquinolone, sulfonamide, trimethoprim, and chloramphenicol antibiotics in urban waters in China.

PubMed

Peng, Xianzhi; Tan, Jianhua; Tang, Caiming; Yu, Yiyi; Wang, Zhendi

2008-01-01

A feasible method has been optimized to simultaneously determine multiclass antibiotic residues, including sulfonamides, fluoroquinolones, trimethoprim, and chloramphenicol in urban riverine water and wastewater by off-line solid phase extraction and high-performance liquid chromatography coupled with a diode-array ultraviolet detector and a fluorescence detector. Internal standard and standard addition methods were used in combination to identify and quantify these antibiotics to compensate for the matrix interference. The method quantification limits (MQLs) were determined to be 0.035 to 0.100 microg/L and 0.100 to 0.300 microg/L for the riverine water and wastewater, respectively. Recoveries of the investigated antibiotics ranged from 63 to 126%. Sulfamethoxazole was the most frequently detected antibiotic residue in Guangzhou section of the Major Pearl River, South China, with a maximum level of 0.510 microg/L. Fluoroquinolone antibiotics were relatively less detected with a maximum level of 0.459 microg/L. The maximum concentration of sulfamethoxazole reached 5.597 microg/L in the raw wastewater from a large-scale sewage treatment plant in Guangzhou city. Around 30% of sulfamethoxazole might survive the primary clarification and biotreatment processes in the sewage treatment plant. None of the investigated antibiotics have been found above MQLs in the final effluent after chlorine disinfection.

Does Disposing of Construction and Demolition Debris in Unlined Landfills Impact Groundwater Quality? Evidence from 91 Landfill Sites in Florida.

PubMed

Powell, Jon T; Jain, Pradeep; Smith, Justin; Townsend, Timothy G; Tolaymat, Thabet M

2015-08-04

More than 1,500 construction and demolition debris (CDD) landfills operate in the United States (U.S.), and U.S. federal regulations do not require containment features such as low-permeability liners and leachate collection systems for these facilities. Here we evaluate groundwater quality from samples collected in groundwater monitoring networks at 91 unlined, permitted CDD landfills in Florida, U.S. A total of 460,504 groundwater sample results were analyzed, with a median of 10 years of quarterly or semiannual monitoring data per site including more than 400 different chemical constituents. Downgradient concentrations of total dissolved solids, sulfate, chloride, iron, ammonia-nitrogen, and aluminum were greater than upgradient concentrations (p < 0.05). At downgradient wells where sulfate concentrations were greater than 150 mg/L (approximately 10% of the maximum dissolved sulfate concentration in water, which suggests the presence of leachate from the landfill), iron and arsenic were detected in 91% and 43% of samples, with median concentrations of 1,900 μg/L and 11 μg/L, respectively. These results show that although health-based standards can be exceeded at unlined CDD landfills, the magnitude of detected chemical concentrations is generally small and reflective of leached minerals from components (wood, concrete, and gypsum drywall) that comprise the bulk of discarded CDD by mass.

Water-quality assessment of the Ozark Plateaus study unit, Arkansas, Kansas, Missouri, and Oklahoma; organic compounds in surface water, bed sediment, and biological tissue, 1992-95

USGS Publications Warehouse

Bell, Richard W.; Davis, Jerri V.; Femmer, Suzanne R.; Joseph, Robert L.

1997-01-01

Organic-compound samples, including pesticides and semi-volatiles, were collected from 1992-95 at 43 surface-water and 27 bed-sediment and biological-tissue sampling sites within the Ozark Plateaus National Water-Quality Assessment Program study unit. Most surface-water, bed-sediment, and biological-tissue sites have drainage basins predominantly in the Springfield and Salem Plateaus. At most surface-water sampling sites, one to three pesticide samples were collected in the spring and early summer of 1994 and 1995; two sites had additional samples collected either weekly, biweekly, or monthly from February 1994 through December 1994. At most bed-sediment and biological-tissue sampling sites, a single organic-compounds sample was collected. Agricultural pesticide use was approximately 4.9 million pounds of active ingredients per year from 1987-91 in the study unit and was generally greatest in the Springfield and Salem Plateaus pasturelands and in the Osage Plains and Mississippi Alluvial Plain cropland areas. The most frequently applied pesticide in the study unit was 2,4-D. Atrazine was the second most frequently applied pesticide. Corn, pasture, rice, sorghum, and soybeans received approximately 85 percent of the pesticides applied within the study unit. The highest pesticide application rate occurred on these crops in the Mississippi Alluvial and Osage Plains. Pastureland was the crop type that received the greatest amount of pesticides in 53 of the 96 counties in the study unit. The most commonly detected herbicide (63 samples) in surface water was atrazine. Five other pesticides--desethylatrazine, tebuthiuron, prometon, metolachlor, and simazine--were detected in 15 or more samples. The most commonly detected insecticide (13 samples) was p,p'-DDE. Two other insecticides, diazinon and cis-permethrin, were detected in seven or more samples. Pesticides were detected at 39 surface-water sites; samples collected at Yocum Creek near Oak Grove, Ark. had the most pesticide detections (13). Seventeen other sites had samples with six or more pesticide detections. Analysis of pesticide data collected at surface-water sites indicates that the largest variety of different pesticides detected (18) was in small, agricultural drainage basins; the largest percentage of detections of a single pesticide (about 80) was in medium, agricultural basins. Pesticide concentrations were small, and in most cases, at or near the detection limit. Maximum concentrations ranged from 0.001 to 0.007 micrograms per liter (mg/L) at small, forest sites; 0.001 to 0.029 mg/L at medium, forest sites; 0.001 to 0.079 mg/L at small, agricultural sites; and 0.003 to 0.29 mg/L at medium, agricultural sites. Pesticides were detected significantly more often in medium, agricultural basins in the Springfield Plateau. The most commonly detected (13 samples) organic compound in bed sediment, in concentrations noticeably above background levels, was 2,6-dimethylnaphthalene; the maximum concentration of 2,6-dimethylnaphthalene was 130 micrograms per kilogram. Seventeen or more compounds were detected in bed-sediment samples collected at three sites. Four compounds were detected in biological-tissue samples: p,p'-DDT in Corbicula fluminea (Asiatic clam) tissue collected at the Osage River near St. Thomas, Mo. and cis-chlordane, trans-chlordane, and trans-nonachlor in C. fluminea tissue collected at the James River near Boaz, Mo. Organic compounds collected at surface-water, bed-sediment, or biological-tissue sampling sites were not detected in concentrations that exceeded any health criteria or standards. Based on this information, organic compounds do not pose any widespread or persistent problems in the study unit.

Arsenic in groundwater of Licking County, Ohio, 2012—Occurrence and relation to hydrogeology

USGS Publications Warehouse

Thomas, Mary Ann

2016-02-23

Arsenic concentrations were measured in samples from 168 domestic wells in Licking County, Ohio, to document arsenic concentrations in a wide variety of wells and to identify hydrogeologic factors associated with arsenic concentrations in groundwater. Elevated concentrations of arsenic (greater than 10.0 micrograms per liter [µg/L]) were detected in 12 percent of the wells (about 1 in 8). The maximum arsenic concentration of about 44 µg/L was detected in two wells in the same township.A subset of 102 wells was also sampled for iron, sulfate, manganese, and nitrate, which were used to estimate redox conditions of the groundwater. Elevated arsenic concentrations were detected only in strongly reducing groundwater. Almost 20 percent of the samples with iron concentrations high enough to produce iron staining (greater than 300 µg/L) also had elevated concentrations of arsenic.In groundwater, arsenic primarily occurs as two inorganic species—arsenite and arsenate. Arsenic speciation was determined for a subset of nine samples, and arsenite was the predominant species. Of the two species, arsenite is more difficult to remove from water, and is generally considered to be more toxic to humans.Aquifer and well-construction characteristics were compiled from 99 well logs. Elevated concentrations of arsenic (and iron) were detected in glacial and bedrock aquifers but were more prevalent in glacial aquifers. The reason may be that the glacial deposits typically contain more organic carbon than the Paleozoic bedrock. Organic carbon plays a role in the redox reactions that cause arsenic (and iron) to be released from the aquifer matrix. Arsenic concentrations were not significantly different for different types of bedrock (sandstone, shale, sandstone/shale, or other). However, arsenic concentrations in bedrock wells were correlated with two well-construction characteristics; higher arsenic concentrations in bedrock wells were associated with (1) shorter open intervals and (2) deeper open intervals, relative to the water level.The spatial distribution of arsenic concentrations was compared to hydrogeologic characteristics of Licking County. Elevated concentrations of arsenic (and iron) were associated with areas of flat topography and thick (greater than 100 feet),clay-rich glacial deposits. These characteristics are conducive to development of strongly reducing redox conditions, which can cause arsenic associated with iron oxyhydroxides in the aquifer matrix to be released to the groundwater.Hydrogeologic characteristics conducive to the development of strongly reducing groundwater are relatively wide-spread in the western part of Licking County, which is part of the Central Lowland physiographic province. In this area, a thick layer of clay-rich glacial deposits obscures the bedrock surface and creates flat to gently rolling landscape with poorly developed drainage networks. In the eastern part of the county, which is part of the Appalachian Plateaus physiographic province, the landscape includes steep-sided valleys and bedrock uplands. In this area, elevated arsenic concentrations were detected in buried valleys but not in the bedrock uplands, where glacial deposits are thin or absent. The observation that elevated concentrations of arsenic (and iron) were more prevalent in the western part of Licking County is true for both glacial and bedrock aquifers.In Licking County, thick, clay-rich glacial deposits (and elevated concentrations of arsenic) are associated with two hydrogeologic settings—buried valley and complex thick drift. Most wells in the buried-valley setting had low arsenic concentrations, but a few samples had very high concentrations (30–44 µg/L) and very reducing redox conditions (methanogenic and near-methanogenic). For wells in the complex-thick-drift setting, elevated arsenic concentrations are more prevalent, but the maximum concentration was lower (about 21 µg/L). Similar observations were made about arsenic concentrations in parts of southwestern Ohio.The hydrogeologic settings and characteristics associated with arsenic in Licking County also exist in other parts of Ohio. The statewide extent of these characteristics roughly corresponds to areas where elevated concentrations of arsenic are known to exist. This preliminary conceptual model can be tested and revised as additional wells are sampled for arsenic.

40 CFR Table 2 to Subpart Dddd of... - Operating Requirements

Code of Federal Regulations, 2012 CFR

2012-07-01

... THC concentration a in the thermal oxidizer exhaust below the maximum concentration established during... average THC concentration a in the catalytic oxidizer exhaust below the maximum concentration established... the range established according to § 63.2262(m) Maintain the 24-hour block average THC concentration a...

40 CFR Table 2 to Subpart Dddd of... - Operating Requirements

Code of Federal Regulations, 2013 CFR

2013-07-01

... THC concentration a in the thermal oxidizer exhaust below the maximum concentration established during... average THC concentration a in the catalytic oxidizer exhaust below the maximum concentration established... the range established according to § 63.2262(m) Maintain the 24-hour block average THC concentration a...

40 CFR Table 2 to Subpart Dddd of... - Operating Requirements

Code of Federal Regulations, 2014 CFR

2014-07-01

... THC concentration a in the thermal oxidizer exhaust below the maximum concentration established during... average THC concentration a in the catalytic oxidizer exhaust below the maximum concentration established... the range established according to § 63.2262(m) Maintain the 24-hour block average THC concentration a...

Determination of Ochratoxin A in wine by packed in-tube solid phase microextraction followed by high performance liquid chromatography coupled to tandem mass spectrometry.

PubMed

Andrade, Mariane A; Lanças, Fernando M

2017-04-14

Ochratoxin A (OTA), a widely studied mycotoxin, can be found in a variety of food matrices. As its concentration in food is generally low (in the order of μg kg -1 ), sample preparation techniques are necessary for the analyte purification and pre-concentration in order to achieve the required low detection limits. The separation and detection methods used for OTA analysis should also offer proper sensitivity in order to allow the adequate quantification of the analyte. This manuscript addresses the development of a methodology aiming the analysis of OTA in wine samples by packed in-tube SPME in flow through extraction mode coupled to HPLC-MS/MS. The in-tube SPME set up utilized a PEEK tube packed with C18 particles as the extraction column. The method was optimized by a central composite design 2 2 +3 extra central points, having as factors the percentage of ACN and time in the sample load step. The functionalities of the method were attested and its analytical conditions, enhanced by using 22% of ACN and 6min in the sample load step. Validation of the method was also accomplished prior to analyses of both dry red wine and dry white wine samples. The method demonstrated proper sensitivity, with detection and quantification limits equal to 0.02 and 0.05μgL -1 , respectively. Linearity and precision exhibited a 0.996 correlation coefficient and RSD under 6%, respectively. The method proved to be accurate at medium and higher concentration levels with a maximum recovery of 73% at higher concentration levels. OTA was not detected in either dry red and dry white wine samples evaluated in this work. If present, it would be at concentrations lower than the detection and quantification limits established for the proposed method, and considered not a potential danger to human health according to our present knowledge. Copyright © 2017 Elsevier B.V. All rights reserved.

Measurements of chlorhexidine, p-chloroaniline, and p-chloronitrobenzene in saliva after mouth wash before and after operation with 0.2% chlorhexidine digluconate in maxillofacial surgery: a randomised controlled trial.

PubMed

Below, H; Assadian, O; Baguhl, R; Hildebrandt, U; Jäger, B; Meissner, K; Leaper, D J; Kramer, A

2017-02-01

Chlorhexidine gluconate is used to prevent the accumulation of dental plaque and gingivitis, infection of the surgical site, and ventilator-associated pneumonia in maxillofacial surgery, but it is not clear whether the metabolites of chlorhexidine are detectable in the patient's saliva at clinically relevant concentrations. Forty-three patients who had orofacial operations were randomised to use a 0.2% chlorhexidine gluconate (n=23), or an octenidine-based, chlorhexidine-free (n=20), mouthwash once preoperatively and three times daily for five postoperative days. After the first, 8.7 (23.3) mg/L chlorhexidine (0.7%-2.5% of the total amount used) was measured in saliva. The concentration increased to 15.2 (6.2) mg/L after the second rinse (first postoperative day), and peaked at 29.4 (11.2) mg/L on the fourth postoperative day. It remained detectable for up to 12hours after the last one, but was not detectable in serum or urine at any time. The potentially carcinogenic metabolite p-chloroaniline was detectable in saliva at higher concentrations in the chlorhexidine group (0.55mg/L) than the octenidine group (0.21mg/L), and p-chloronitrobenzene was detected in both groups in only minimal concentrations (0.001-0.21mg/L). Chlorhexidine gluconate mouthwashes do increase the concentration of p-chloroaniline, but a single use seems to be safe. Whether prolonged exposure over many years may have carcinogenic potential is still not clear. Based on the hitherto unknown kinetics of p-chloroaniline in saliva, the recent recommendation of the Federal Drug Administration (FDA) in the USA to limit the use of a chlorhexidine gluconate mouthwash to a maximum of six months seems to be justified. Copyright © 2016 The British Association of Oral and Maxillofacial Surgeons. All rights reserved.

Environmental occurrence and shallow ground water detection of the antibiotic monensin from dairy farms

USGS Publications Warehouse

Watanabe, N.; Harter, T.H.; Bergamaschi, B.A.

2008-01-01

Pharmaceuticals used in animal feeding operations have been detected in various environmental settings. There is a growing concern about the impact on terrestrial and aquatic organisms and the development of antibiotic-resistant strains of microorganisms. Pharmaceutical use in milking cows is relatively limited compared with other livestock operations, except for the ionophore monensin, which is given to lactating cows as a feed. By weight, monensin can be the most significant antibiotic used in a dairy farm. This study investigates the potential of monensin to move from dairy operations into the surrounding ground water. Using two dairy farms in California as study sites, we twice collected samples along the environmental pathway - from flush lanes, lagoon waters, and shallow ground water beneath the dairies and beneath its associated manured fields. Monensin concentrations were determined using solid-phase extraction and liquid chromatography-tandem mass spectrometry with positive electrospray ionization. Monensin was detected in all of the flush lane and lagoon water samples. Theoretical maximum concentration estimated from the actual dosing rate and the theoretical excretion rate assuming no attenuation was one order of magnitude greater than observed concentrations, suggesting significant attenuation in the manure collection and storage system. Monensin was also detected, at levels ranging from 0.04 to 0.39 ??g L-1, in some of the ground water samples underneath the production area of the dairy but not from the adjacent manured fields. Concentrations in ground water immediately downgradient of the lagoons were one to two orders of magnitude lower than the concentrations detected in lagoons, suggesting attenuation in the subsurface. The data suggest the possibility of monensin transport into shallow (2-5 m) alluvial ground water from dairy management units, including manure storage lagoons and freestalls occupied by heifers, lactating cows, and dry cows. Copyright ?? 2008 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.

Detection limits of antimicrobials in ewe milk by delvotest photometric measurements.

PubMed

Althaus, R L; Torres, A; Montero, A; Balasch, S; Molina, M P

2003-02-01

The Delvotest method detection limits per manufacturer's instructions at a fixed reading time of 3 h for 24 antimicrobial agents were determined in ewe milk by photometric measurement. For each drug, eight concentrations were tested on 20 ewe milk samples from individual ewes. Detection limits, determined by means of logistic regression models, were (microg/kg): 3, amoxycillin; 2, ampicillin; 18, cloxacillin; 1, penicillin "G"; 34, cefadroxil; 430, cephalosporin "C"; 40, cephalexin; 20, cefoperazone; 33, Ceftiofur; 18, cefuroxime; 6100, streptomycin; 1200, gentamycin; 2600, neomycin; 830, erythromycin; 100, tylosin; 180, doxycycline; 320, oxytetracycline; 590, tetracycline; 88, sulfadiazine; 44, sulfamethoxazole; 140, sulfametoxypyridazine; 48, sulfaquinoxaline; 12,000, chloramphenicol; and 290, trimethoprim. Whereas the beta-lactam antibiotics, sulphonamides, and tylosin were detected by Delvotest method at levels equal to those of maximum residue limits, its sensitivity needs to be enhanced to detect aminoglycosides, tetracyclines, streptomycin, chloramphenicol, and trimethoprim residues in ewe milk or to develop an integrated residue detection system for ewe milk with different sensitive microorganisms for each group of antiinfectious agents.

Surface runoff and subsurface tile drain losses of neonicotinoids and companion herbicides at edge-of-field.

PubMed

Chrétien, François; Giroux, Isabelle; Thériault, Georges; Gagnon, Patrick; Corriveau, Julie

2017-05-01

With their application as seed coatings, the use of neonicotinoid insecticides increased dramatically during the last decade. They are now frequently detected in aquatic ecosystems at concentrations susceptible to harm aquatic invertebrates at individual and population levels. This study intent was to document surface runoff and subsurface tile drain losses of two common neonicotinoids (thiamethoxam and clothianidin) compared to those of companion herbicides (atrazine, glyphosate, S-metolachlor and mesotrione) at the edge of a 22.5-ha field under a corn-soybean rotation. A total of 14 surface runoff and tile drain discharge events were sampled over two years. Events and annual unit mass losses were computed using flow-weighted concentrations and total surface runoff and tile drain flow volumes. Detection frequencies close to 100% in edge-of-field surface runoff and tile drain water samples were observed for thiamethoxam and clothianidin even though only thiamethoxam had been applied in the first year. In 2014, thiamethoxam median concentrations in surface runoff and tile drain samples were respectively 0.46 and 0.16 μg/L, while respective maximum concentrations of 2.20 and 0.44 μg/L were measured in surface runoff and tile drain samples during the first post-seeding storm event. For clothianidin, median concentrations in surface runoff and tile drain samples were 0.02 and 0.01, μg/L, and respective maximum concentrations were 0.07 μg/L and 0.05 μg/L. Surface runoff and tile drain discharge were key transport mechanisms with similar contributions of 53 and 47% of measured mass losses, respectively. Even if thiamethoxam was applied at a relatively low rate and had a low mass exportation value (0.3%), the relative toxicity was one to two orders of magnitude higher than those of the other chemicals applied in 2014 and 2015. Companion herbicides, except glyphosate in tile drains, exceeded their water quality guideline during one sampling campaign after application but rapidly resumed below these limits. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

The effect of isoenzyme-selective PDE inhibitors on methacholine-induced contraction of guinea-pig and rat ileum.

PubMed Central

Tomkinson, A.; Raeburn, D.

1996-01-01

1. We have examined the effects of the isoenzyme-selective phosphodiesterase (PDE) inhibitors, vinpocetine (type 1), siguazodan (type 3), rolipram (type 4) and zaprinast (type 5) and the non-selective PDE inhibitor enprofylline on methacholine (MCh) contractile concentration-response curves on guinea-pig and rat isolated ileum. 2. In guinea-pig ileum, vinpocetine (10-300 microM), zaprinast (1-300 microM) and enprofylline (100-1000 microM) produced a concentration-dependent depression of the maximum response (Emax) to MCh only without effect on the MCh EC50 values (rank order of potency: zaprinast > vinpocetine > enprofylline). In contrast, siguazodan (10-300 microM) and rolipram (10-300 microM) produced a rightward displacement of the MCh concentration-response curve (increase in EC50: rank order; rolipram > siguazodan), with effects on the MCh maximum seen only at higher concentrations. 3. In the rat ileum, vinpocetine (10-300 microM), zaprinast (0.1-300 microM) and enprofylline (100-1000 microM) caused depression of the MCh maximum contraction (rank order: zaprinast > vinpocetine > enprofylline). Low concentrations of rolipram and siguazodan had no significant effect on the MCh maximum. In the presence of higher concentrations (> 100 microM) of rolipram and siguazodan, a maximum response was not achieved at the highest concentration of MCh tested. As in the guinea-pig ileum, only rolipram (10-300 microM) and siguazodan (10-300 microM) produced a significant, concentration-dependent, rightward displacement of the MCh concentration-response curve (increase in EC50: rank order: rolipram > siguazodan). 4. In the guinea-pig ileum, isoprenaline (0.1 microM) produced a rightward displacement (approximately 3 fold) of the MCh concentration-response curve, accompanied by a significant depression of the maximum response. Increasing the isoprenaline concentration (1 microM) had no further effect on either parameter. Sodium nitroprusside (SNP, > or = 10 microM) produced a concentration-dependent depression of the MCh maximum without an effect on the EC50. 5. In the rat ileum, isoprenaline (1 microM) produced a concentration-dependent rightward displacement (approximately 2.8 fold) of the MCh concentration-response curve with depression of the MCh maximum at higher (> or = 100 microM) concentrations. SNP produced depression of the MCh maximum at a concentration of 10 microM and above. Effects on the MCh EC50 were seen only at 100 and 300 microM. 6. In guinea-pig ileum, isoprenaline (0.1 microM) in combination with rolipram (10 microM) further increased the MCh EC50 and reduced the MCh maximum. The combination of SNP (10 microM) with zaprinast (0.1 microM) produced no further significant effect than SNP alone. 7. In rat ileum, isoprenaline (1 microM) in combination with rolipram (10 microM) further increased the EC50 and reduced the maximum. SNP (10 microM) had no significant effect on either the MCh maximum or EC50. A combination with zaprinast (1 microM) had no further effect. 8. In conclusion, all the PDE inhibitors tested produced a concentration-dependent inhibition of the MCh concentration-response curve, indicating a modulator role for the PDE isoenzymes in gastrointestinal smooth muscle contractility. The PDE inhibitors that elevate cyclic GMP produced a depression of the MCh maximum response only, whilst those that elevate cyclic AMP produced a rightward displacement of the MCh concentration-response curve. This was confirmed by the use of isoprenaline and SNP. This difference in the type of inhibition produced by these PDE isoenzyme inhibitors may reflect a different intracellular site/mechanism by which the cyclic AMP- and cyclic GMP-activated kinases act functionally to antagonize the contractile response. PMID:8864552

Short-term effect of ammonia concentration and salinity on activity of ammonia oxidizing bacteria.

PubMed

Claros, J; Jiménez, E; Borrás, L; Aguado, D; Seco, A; Ferrer, J; Serralta, J

2010-01-01

A continuously aerated SHARON (single reactor high activity ammonia removal over nitrite) system has been operated to achieve partial nitritation. Two sets of batch experiments were carried out to study the effect of ammonia concentration and salinity on the activity of ammonia-oxidizing bacteria (AOB). Activity of AOB raised as free ammonia concentration was increased reaching its maximum value at 4.5 mg NH3-N l(-1). The half saturation constant for free ammonia was determined (K(NH3)=0.32 mg NH3-N l(-1)). Activity decreased at TAN (total ammonium-nitrogen) concentration over 2,000 mg NH4-N l(-1). No free ammonia inhibition was detected. The effect of salinity was studied by adding different concentrations of different salts to the biomass. No significant differences were observed between the experiments carried out with a salt containing or not containing NH4. These results support that AOB are inhibited by salinity, not by free ammonia. A mathematical expression to represent this inhibition is proposed. To compare substrate affinity and salinity inhibitory effect on different AOB populations, similar experiments were carried out with biomass from a biological nutrient removal pilot plant. The AOB activity reached its maximum value at 0.008 mg NH3-N l(-1) and decreased at TAN concentration over 400 mg NH4-N l(-1). These differences can be explained by the different AOB predominating species: Nitrosomonas europaea and N. eutropha in the SHARON biomass and Nitrosomonas oligotropha in the pilot plant.

Evaluation of the Alphasense Optical Particle Counter (OPC-N2) and the Grimm Portable Aerosol Spectrometer (PAS-1.108)

PubMed Central

Sousan, Sinan; Koehler, Kirsten; Hallett, Laura; Peters, Thomas M.

2017-01-01

We compared the performance of a low-cost (∼$500), compact optical particle counter (OPC, OPC-N2, Alphasense) to another OPC (PAS-1.108, Grimm Technologies) and reference instruments. We measured the detection efficiency of the OPCs by size from 0.5 to 5 μm for monodispersed, polystyrene latex (PSL) spheres. We then compared number and mass concentrations measured with the OPCs to those measured with reference instruments for three aerosols: salt, welding fume and Arizona road dust. The OPC-N2 detection efficiency for monodispersed was similar to the PAS-1.108 for particles larger than 0.8 μm (minimum of 79% at 1 μm and maximum of 101% at 3 μm). For 0.5-μm particles, the detection efficiency of OPCN2 was underestimated at 78%, whereas PAS-1.108 overestimated concentrations by 183%. The mass concentrations from the OPCs were linear (r ≥ 0.97) with those from the reference instruments for all aerosols, although the slope and intercept were different. The mass concentrations were overestimated for dust (OPC-N2, slope = 1.6; PAS-1.108, slope = 2.7) and underestimated for welding fume (OPC-N2, slope = 0.05; PAS-1.108, slope = 0.4). The coefficient of variation (CV, precision) for OPC-N2 for all experiments was between 4.2% and 16%. These findings suggest that, given site-specific calibrations, the OPC-N2 can provide number and mass concentrations similar to the PAS-1.108 for particles larger than 1 μm. PMID:28871213

Occurrence of perfluoroalkyl acids in environmental waters in Vietnam.

PubMed

Duong, Hanh Thi; Kadokami, Kiwao; Shirasaka, Hanako; Hidaka, Rento; Chau, Hong Thi Cam; Kong, Lingxiao; Nguyen, Trung Quang; Nguyen, Thao Thanh

2015-03-01

This is the first nationwide study of perfluoroalkyl acids (PFAAs) in environmental waters in Vietnam. Twenty-eight river water and 22 groundwater samples collected in four major cities and 14 river water samples from the Red River were screened to investigate the occurrence and sources of 16 PFAAs. Perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), and perfluorononanoic acid (PFNA) were the most prevalent of 11 detected PFAAs with maximum concentrations in urban river water of 5.3, 18 and 0.93ngL(-1), respectively, and in groundwater of 8.2, 4.5 and 0.45ngL(-1), respectively. PFAAs in the Red River water were detected at low levels. PFAA concentrations in river water were higher in the rainy season than in the dry season, possibly due to storm water runoff, a common phenomenon in Southeast Asian countries. The highest concentrations of PFAAs in river water were observed in samples from highly populated and industrialized areas, perhaps sourced from sewage. The PFAA concentrations observed were similar to those in other Southeast Asian countries, but lower than in developed nations. From the composition profiles of PFAAs, industrial products containing PFAAs imported from China and Japan might be one of the major sources of PFAAs in the Vietnamese aquatic environment. According to the health-based values and advisory issued by the United States Environmental Protection Agency (USEPA), the concentrations of detected PFAAs in this study do not pose an immediate health risk to humans and aquatic organisms. Copyright © 2014 Elsevier Ltd. All rights reserved.

Evaluation of the Alphasense Optical Particle Counter (OPC-N2) and the Grimm Portable Aerosol Spectrometer (PAS-1.108).

PubMed

Sousan, Sinan; Koehler, Kirsten; Hallett, Laura; Peters, Thomas M

2016-01-01

We compared the performance of a low-cost (∼$500), compact optical particle counter (OPC, OPC-N2, Alphasense) to another OPC (PAS-1.108, Grimm Technologies) and reference instruments. We measured the detection efficiency of the OPCs by size from 0.5 to 5 μm for monodispersed, polystyrene latex (PSL) spheres. We then compared number and mass concentrations measured with the OPCs to those measured with reference instruments for three aerosols: salt, welding fume and Arizona road dust. The OPC-N2 detection efficiency for monodispersed was similar to the PAS-1.108 for particles larger than 0.8 μm (minimum of 79% at 1 μm and maximum of 101% at 3 μm). For 0.5-μm particles, the detection efficiency of OPCN2 was underestimated at 78%, whereas PAS-1.108 overestimated concentrations by 183%. The mass concentrations from the OPCs were linear (r ≥ 0.97) with those from the reference instruments for all aerosols, although the slope and intercept were different. The mass concentrations were overestimated for dust (OPC-N2, slope = 1.6; PAS-1.108, slope = 2.7) and underestimated for welding fume (OPC-N2, slope = 0.05; PAS-1.108, slope = 0.4). The coefficient of variation (CV, precision) for OPC-N2 for all experiments was between 4.2% and 16%. These findings suggest that, given site-specific calibrations, the OPC-N2 can provide number and mass concentrations similar to the PAS-1.108 for particles larger than 1 μm.

Runoff of pharmaceuticals and personal care products following application of dewatered municipal biosolids to an agricultural field.

PubMed

Sabourin, Lyne; Beck, Andrew; Duenk, Peter W; Kleywegt, Sonya; Lapen, David R; Li, Hongxia; Metcalfe, Chris D; Payne, Michael; Topp, Edward

2009-08-01

Municipal biosolids are a useful source of nutrients for crop production, and commonly used in agriculture. In this field study, we applied dewatered municipal biosolids at a commercial rate using broadcast application followed by incorporation. Precipitation was simulated at 1, 3, 7, 21 and 34 days following the application on 2 m(2) microplots to evaluate surface runoff of various pharmaceuticals and personal care products (PPCPs), namely atenolol, carbamazepine, cotinine, caffeine, gemfibrozil, naproxen, ibuprofen, acetaminophen, sulfamethoxazole, triclosan and triclocarban. There was little temporal coherence in the detection of PPCPs in runoff, various compounds being detected maximally on days 1, 3, 7 or 36. Maximum concentrations in runoff ranged from below detection limit (gemfibrozil) to 109.7 ng L(-1) (triclosan). Expressing the total mass exported as a percentage of that applied, some analytes revealed little transport potential (<1% exported; triclocarban, triclosan, sulfamethoxazole, ibuprofen, naproxen and gemfibrozil) whereas others were readily exported (>1% exported; acetaminophen, carbamazepine, caffeine, cotinine, atenolol). Those compounds with little transport potential had log K(ow) values of 3.18 or greater, whereas those that were readily mobilized had K(ow) values of 2.45 or less. Maximal concentrations of all analytes were below toxic concentrations using a variety of endpoints available in the literature. In summary, this study has quantified the transport potential in surface runoff of PPCPs from land receiving biosolids, identified that log K(ow) may be a determinant of runoff transport potential of these analytes, and found maximal concentrations of all chemicals tested to be below toxic concentrations using a variety of endpoints.

Relation of water chemistry of the Edwards aquifer to hydrogeology and land use, San Antonio Region, Texas

USGS Publications Warehouse

Buszka, Paul M.

1987-01-01

In general, the quality of ground water in the freshwater parts of the aquifer (north of the "bad-water" line) is suitable for all uses including human consumption. Two areas that are exceptions are: (1) Northeast of Garner Field in Uvalde, Texas, where PCE (tetrachloroethylene) has been detected in groundwater samples, and (2) north-central Bexar County near the former West Avenue landfill where PCE and benzene have been detected in ground-water samples. Concentrations of these organic compounds in water from many wells in the two areas exceed the maximum contaminant level for human consumption set by the U.S. Environmental Protection Agency.

Impact of glyphosate-tolerant soybean and glufosinate-tolerant corn production on herbicide losses in surface runoff.

PubMed

Shipitalo, Martin J; Malone, Robert W; Owens, Lloyd B

2008-01-01

Residual herbicides used in the production of soybean [Glycine max (L.) Merr] and corn (Zea mays L.) are often detected in surface runoff at concentrations exceeding their maximum contaminant levels (MCL) or health advisory levels (HAL). With the advent of transgenic, glyphosate-tolerant soybean and glufosinate-tolerant corn this concern might be reduced by replacing some of the residual herbicides with short half-life, strongly sorbed, contact herbicides. We applied both herbicide types to two chiseled and two no-till watersheds in a 2-yr corn-soybean rotation and at half rates to three disked watersheds in a 3-yr corn/soybean/wheat (Triticum aestivum L.)-red clover (Trifolium pratense L.) rotation and monitored herbicide losses in runoff water for four crop years. In soybean years, average glyphosate loss (0.07%) was approximately 1/7 that of metribuzin (0.48%) and about one-half that of alachlor (0.12%), residual herbicides it can replace. Maximum, annual, flow-weighted concentration of glyphosate (9.2 microg L(-1)) was well below its 700 microg L(-1) MCL and metribuzin (9.5 microg L(-1)) was well below its 200 microg L(-1) HAL, whereas alachlor (44.5 microg L(-1)) was well above its 2 microg L(-1) MCL. In corn years, average glufosinate loss (0.10%) was similar to losses of alachlor (0.07%) and linuron (0.15%), but about one-fourth that of atrazine (0.37%). Maximum, annual, flow-weighted concentration of glufosinate (no MCL) was 3.5 microg L(-1), whereas atrazine (31.5 microg L(-1)) and alachlor (9.8 microg L(-1)) substantially exceeded their MCLs of 3 and 2 microg L(-1), respectively. Regardless of tillage system, flow-weighted atrazine and alachlor concentrations exceeded their MCLs in at least one crop year. Replacing these herbicides with glyphosate and glufosinate can reduce the occurrence of dissolved herbicide concentrations in runoff exceeding drinking water standards.

Polyfluorinated compounds in ambient air from ship- and land-based measurements in northern Germany

NASA Astrophysics Data System (ADS)

Dreyer, Annekatrin; Ebinghaus, Ralf

Neutral volatile and semi-volatile polyfluorinated organic compounds (PFC) and ionic perfluorinated compounds were determined in air samples collected at two sites in the vicinity of Hamburg, Germany, and onboard the German research vessel Atair during a cruise in the German Bight, North Sea, in early November 2007. PUF/XAD-2/PUF cartridges and glass fiber filters as sampling media were applied to collect several fluorotelomer alcohols (FTOH), fluorotelomer acrylates (FTA), perfluoroalkyl sulfonamides (FASA), and perfluoroalkyl sulfonamido ethanols (FASE) in the gas- and particle-phase as well as a set of perfluorinated carboxylates (PFCA) and sulfonates (PFSA) in the particle-phase. This study presents the distribution of PFC in ambient air of the German North Sea and in the vicinity of Hamburg for the first time. Average total PFC concentrations in and around Hamburg (180 pg m -3) were higher than those observed in the German Bight (80 pg m -3). In the German Bight, minimum-maximum gas-phase concentrations of 17-82 pg m -3 for ΣFTOH, 2.6-10 pg m -3 for ΣFTA, 10-15 pg m -3 for ΣFASA, and 2-4.4 pg m -3 for ΣFASE were determined. In the vicinity of Hamburg, minimum-maximum gas-phase concentrations of 32-204 pg m -3 for ΣFTOH, 3-26 pg m -3 for ΣFTA, 3-18 pg m -3 for ΣFASA, and 2-15 pg m -3 for ΣFASE were detected. Concentrations of perfluorinated acids were in the range of 1-11 pg m -3. FTOH clearly dominated the substance spectrum; 8:2 FTOH occurred in maximum proportions. Air mass back trajectories, cluster, and correlation analyses revealed that the air mass origin and thus medium to long range atmospheric transport was the governing parameter for the amount of PFC in ambient air. Southwesterly located source regions seemed to be responsible for elevated PFC concentrations, local sources appeared to be of minor importance.

Improved Sensitivity with Low Limit of Detection of a Hydrogen Gas Sensor Based on rGO-Loaded Ni-Doped ZnO Nanostructures.

PubMed

Bhati, Vijendra Singh; Ranwa, Sapana; Rajamani, Saravanan; Kumari, Kusum; Raliya, Ramesh; Biswas, Pratim; Kumar, Mahesh

2018-04-04

We report enhanced hydrogen-gas-sensing performance of a Ni-doped ZnO sensor decorated with the optimum concentration of reduced graphene oxide (rGO). Ni-doped ZnO nanoplates were grown by radio frequency sputtering, rGO was synthesized by Hummer's method and decorated by the drop cast method of various concentration of rGO (0-1.5 wt %). The current-voltage characteristics of the rGO-loaded sensor are highly influenced by the loading concentration of rGO, where current conduction decreases and sensor resistance increases as the rGO concentration is increased up to 0.75 wt % because of the formation of various Schottky heterojunctions at rGO/ZnO interfaces. With the combined effect of more active site availability and formation of various p-n heterojunctions due to the optimum loading concentration of rGO (0.75 wt %), the sensor shows the maximum sensing response of ∼63.8% for 100 ppm hydrogen at moderate operating temperature (150 °C). The rGO-loaded sensors were able to detect a minimum of 1 ppm hydrogen concentration and showed high selectivity. However, a further increase in the rGO concentration (1.5 wt %) leads to the reduction of the relative response of hydrogen gas, ascribed to the formation of interconnections of rGO between electrodes. Therefore, it reduces the total resistance of the sensor and minimizes the effect of p-n heterojunction on sensor response.

A Search for Extraterrestrial Amino Acids in Polar Ice: A Progress Report

NASA Technical Reports Server (NTRS)

Bada, Jeffrey L.; Brinton, Karen L. F.; McDonald, Gene D.; Wang, Xueyun

1996-01-01

Fifteen polar ice samples-fourteen from Greenland and one from Antarctica-have been analyzed for the extraterrestrial amino acid alpha-aminoisobutyric acid (AIB) in an effort to estimate the flux of interplanetary organic material to the Earth's surface. Only one sample (Greenland GISP II, 4270-4440 years old) contains detectable amounts of AIB, apparently the signature of a transient delivery event. The maximum oceanic concentration of AIB from such an event would be less than 10(exp-9) M.

The use of gas chromatographic-mass spectrometric-computer systems in pharmacokinetic studies.

PubMed

Horning, M G; Nowlin, J; Stafford, M; Lertratanangkoon, K; Sommer, K R; Hill, R M; Stillwell, R N

1975-10-29

Pharmacokinetic studies involving plasma, urine, breast milk, saliva and liver homogenates have been carried out by selective ion detection with a gas chromatographic-mass spectrometric-computer system operated in the chemical ionization mode. Stable isotope labeled drugs were used as internal standards for quantification. The half-lives, the concentration at zero time, the slope (regression coefficient), the maximum velocity of the reaction and the apparent Michaelis constant of the reaction were determined by regression analysis, and also by graphic means.

Mycotoxins: diffuse and point source contributions of natural contaminants of emerging concern to streams

USGS Publications Warehouse

Kolpin, Dana W.; Schenzel, Judith; Meyer, Michael T.; Phillips, Patrick J.; Hubbard, Laura E.; Scott, Tia-Marie; Bucheli, Thomas D.

2014-01-01

To determine the prevalence of mycotoxins in streams, 116 water samples from 32 streams and three wastewater treatment plant effluents were collected in 2010 providing the broadest investigation on the spatial and temporal occurrence of mycotoxins in streams conducted in the United States to date. Out of the 33 target mycotoxins measured, nine were detected at least once during this study. The detections of mycotoxins were nearly ubiquitous during this study even though the basin size spanned four orders of magnitude. At least one mycotoxin was detected in 94% of the 116 samples collected. Deoxynivalenol was the most frequently detected mycotoxin (77%), followed by nivalenol (59%), beauvericin (43%), zearalenone (26%), β-zearalenol (20%), 3-acetyl-deoxynivalenol (16%), α-zearalenol (10%), diacetoxyscirpenol (5%), and verrucarin A (1%). In addition, one or more of the three known estrogenic compounds (i.e. zearalenone, α-zearalenol, and β-zearalenol) were detected in 43% of the samples, with maximum concentrations substantially higher than observed in previous research. While concentrations were generally low (i.e. < 50 ng/L) during this study, concentrations exceeding 1000 ng/L were measured during spring snowmelt conditions in agricultural settings and in wastewater treatment plant effluent. Results of this study suggest that both diffuse (e.g. release from infected plants and manure applications from exposed livestock) and point (e.g. wastewater treatment plants and food processing plants) sources are important environmental pathways for mycotoxin transport to streams. The ecotoxicological impacts from the long-term, low-level exposures to mycotoxins alone or in combination with complex chemical mixtures are unknown

40 CFR 75.72 - Determination of NOX mass emissions for common stack and multiple stack configurations.

Code of Federal Regulations, 2012 CFR

2012-07-01

... the affected units as the difference between NOX mass emissions measured in the common stack and NOX... emissions using the maximum potential NOX emission rate, the maximum potential flow rate, and either the maximum potential CO2 concentration or the minimum potential O2 concentration (as applicable). The maximum...

The distribution of bromide in water in the Floridan aquifer system, Duval County, northeastern Florida

USGS Publications Warehouse

German, E.R.; Taylor, G.F.

1995-01-01

Although Duval County, Florida, has ample ground-water resources for public supply, the potential exists for a problem with excessive disinfectant by-products. These disinfectant by-products result from the treatment of raw water containing low concentrations of bromide and naturally occurring organic compounds. Because of this potential problem, the relation of bromide concentrations to aquifer tapped, well location and depth, and chemical characteristics of water in the Floridan aquifer system underlying Duval County were studied to determine if these relations could be applied to delineate water with low-bromide concentrations for future supplies. In 1992, water samples from 106 wells that tap the Floridan aquifer system were analyzed for bromide and major dissolved constituents. A comparison of bromide concentrations from the 1992 sampling with data from earlier studies (1979-80) indicates that higher bromide concentrations were detected during the earlier studies. The difference between the old and new data is probably because of a change in analytical methodology in the analysis of samples. Bromide concentrations exceeded the detection limit (0.10 milligrams per liter) in water from 28 of the 106 wells (26 percent) sampled in 1992. The maximum concentration was 0.56 milligrams per liter. There were no relations between bromide and major dissolved constituents, well depth, or aquifer tapped that would be useful for determining bromide concentrations. Areal patterns of bromide occurrence are not clearly defined, but areas with relatively high bromide concentrations tend to be located in a triangular area near the community of Sunbeam, Florida, and along the St. Johns River throughout Duval County.

Occurrence and seasonal distribution of polycyclic aromatic hydrocarbons and legacy and current-use pesticides in air from a Mediterranean coastal lagoon (Mar Menor, SE Spain).

PubMed

Carratalá, A; Moreno-González, R; León, V M

2017-01-01

The occurrence and seasonal distribution of polycyclic aromatic hydrocarbons (PAHs) and legacy and current-use pesticides (CUPs) in air were characterized around the Mar Menor lagoon using both active and passive sampling devices. The seasonal distribution of these pollutants was determined at 6 points using passive samplers. Passive sampler sampling rates were estimated for all detected analytes using an active sampler, considering preferentially winter data, due to probable losses in active sampling during summer (high temperatures and solar irradiation). The presence of 28 compounds (14 CUPs, 11 PAHs and 3 organochlorinated pesticides) were detected in air by polyurethane passive sampling. The most commonly detected contaminants (>95% of samples) in air were chlorpyrifos, chlorpyrifos-methyl and phenanthrene. The maximum concentrations corresponded to phenanthrene (6000 pg m -3 ) and chlorpyrifos (4900 pg m -3 ). The distribution of contaminants was spatially and seasonally heterogeneous. The highest concentrations of PAHs were found close to the airport, while the highest concentrations of pesticides were found in the influence area of agricultural fields (western stations). PAH and herbicide concentrations were higher in winter than in the other seasons, although some insecticides such as chlorpyrifos were more abundant in autumn. The presence of PAHs and legacy and current-use pesticides in air confirmed their transference potential to marine coastal areas such as the Mar Menor lagoon. Copyright © 2016 Elsevier Ltd. All rights reserved.

A novel inhibition based biosensor using urease nanoconjugate entrapped biocomposite membrane for potentiometric glyphosate detection.

PubMed

Vaghela, Chetana; Kulkarni, Mohan; Haram, Santosh; Aiyer, Rohini; Karve, Meena

2018-03-01

A potentiometric biosensor based on agarose-guar gum (A-G) entrapped bio-nanoconjugate of urease with gold nanoparticles (AUNps), has been reported for the first time for glyphosate detection. The biosensor is based on inhibition of urease activity by glyphosate, which was measured by direct potentiometry using ammonium ion selective electrode covered with A-G-urease nanoconjugate membrane. TEM and FTIR analysis revealed nanoconjugate formation and its immobilization in A-G matrix respectively. The composite biopolymer employed for immobilization yields thin, transparent, flexible membrane having superior mechanical strength and stability. It retains the maximum activity (92%) of urease with negligible leaching. The conjugation of urease with AUNps allows improvement in response characteristics for potentiometric measurement. The biosensor shows a linear response in the glyphosate concentration range from 0.5ppm-50ppm, with limit of detection at 0.5ppm, which covers maximum residual limit set by WHO for drinking water. The inhibition of catalytic activity of urease nanoconjugate by gyphosate was confirmed by FTIR analysis. The response of fabricated biosensor is selective towards glyphosate as against various other pesticides. The biosensor exhibits good performance in terms of reproducibility and prolonged storage stability of 180days. Thus, the present biosensor provides an alternative method for simple, selective and cost effective detection of glyphosate based on urease inhibition. Copyright © 2017 Elsevier B.V. All rights reserved.

Industry-Wide Surveillance of Marek's Disease Virus on Commercial Poultry Farms.

PubMed

Kennedy, David A; Cairns, Christopher; Jones, Matthew J; Bell, Andrew S; Salathé, Rahel M; Baigent, Susan J; Nair, Venugopal K; Dunn, Patricia A; Read, Andrew F

2017-06-01

Marek's disease virus is a herpesvirus of chickens that costs the worldwide poultry industry more than US$1 billion annually. Two generations of Marek's disease vaccines have shown reduced efficacy over the last half century due to evolution of the virus. Understanding where the virus is present may give insight into whether continued reductions in efficacy are likely. We conducted a 3-yr surveillance study to assess the prevalence of Marek's disease virus on commercial poultry farms, determine the effect of various factors on virus prevalence, and document virus dynamics in broiler chicken houses over short (weeks) and long (years) timescales. We extracted DNA from dust samples collected from commercial chicken and egg production facilities in Pennsylvania, USA. Quantitative PCR was used to assess wild-type virus detectability and concentration. Using data from 1018 dust samples with Bayesian generalized linear mixed effects models, we determined the factors that correlated with virus prevalence across farms. Maximum likelihood and autocorrelation function estimation on 3727 additional dust samples were used to document and characterize virus concentrations within houses over time. Overall, wild-type virus was detectable at least once on 36 of 104 farms at rates that varied substantially between farms. Virus was detected in one of three broiler-breeder operations (companies), four of five broiler operations, and three of five egg layer operations. Marek's disease virus detectability differed by production type, bird age, day of the year, operation (company), farm, house, flock, and sample. Operation (company) was the most important factor, accounting for between 12% and 63.4% of the variation in virus detectability. Within individual houses, virus concentration often dropped below detectable levels and reemerged later. These data characterize Marek's disease virus dynamics, which are potentially important to the evolution of the virus.

Plasma appearance and correlation between coffee and green tea metabolites in human subjects.

PubMed

Renouf, Mathieu; Guy, Philippe; Marmet, Cynthia; Longet, Karin; Fraering, Anne-Lise; Moulin, Julie; Barron, Denis; Dionisi, Fabiola; Cavin, Christophe; Steiling, Heike; Williamson, Gary

2010-12-01

Coffee and green tea are two of the most widely consumed hot beverages in the world. Their respective bioavailability has been studied separately, but absorption of their respective bioactive phenolics has not been compared. In a randomised cross-over design, nine healthy subjects drank instant coffee and green tea. Blood samples were collected over 12 h and at 24 h to assess return to baseline. After green tea consumption, (-)-epigallocatechin (EGC) was the major catechin, appearing rapidly in the plasma; (-)-EGC gallate (EGCg) and (-)-epicatechin (EC) were also present, but (-)-EC gallate and C were not detected. Dihydroferulic acid and dihydrocaffeic acid were the major metabolites that appeared after coffee consumption with a long time needed to reach maximum plasma concentration, suggesting metabolism and absorption in the colon. Other phenolic acid equivalents (caffeic acid (CA), ferulic acid (FA) and isoferulic acid (iFA)) were detected earlier, and they peaked at lower concentrations. Summations of the plasma area under the curves (AUC) for the measured metabolites showed 1.7-fold more coffee-derived phenolic acids than green tea-derived catechins (P = 0.0014). Furthermore, we found a significant correlation between coffee metabolites based on AUC. Inter-individual differences were observed, but individuals with a high level of CA also showed a correspondingly high level of FA. However, no such correlation was observed between the tea catechins and coffee phenolic acids. Correlation between AUC and maximum plasma concentration was also significant for CA, FA and iFA and for EGCg. This implies that the mechanisms of absorption for these two classes of compounds are different, and that a high absorber of phenolic acids is not necessarily a high absorber of catechins.

Dissipation and runoff transport of metazachlor herbicide in rapeseed cultivated and uncultivated plots in field conditions.

PubMed

Mantzos, Nikolaos; Hela, Dimitra; Karakitsou, Anastasia; Antonopoulou, Maria; Konstantinou, Ioannis

2016-10-01

The environmental fate of metazachlor herbicide was investigated under field conditions in rapeseed cultivated and uncultivated plots, over a period of 225 days. The cultivation was carried out in silty clay soil plots with two surface slopes, 1 and 5 %. The herbicide was detectable in soil up to 170 days after application (DAA), while the dissipation rate was best described by first-order kinetics and its half-life ranged between 10.92 and 12.68 days. The herbicide was detected in the soil layer of 10-20 cm from 5 to 48 DAA, and its vertical movement can be described by the continuous stirred tank reactor (CSTR) in series model. Relatively low amounts of metazachlor (less than 0.31 % of the initial applied active ingredient) were transferred by runoff water. More than 80 % of the total losses were transferred at the first runoff event (12 DAA), with herbicide concentrations in runoff water ranging between 70.14 and 79.67 μg L -1 . Minor amounts of the herbicide (less than 0.07 % of the initial applied active ingredient) were transferred by the sediment, with a maximum concentration of 0.57 μg g -1 (12 DAA), in plots with 5 % inclination. Finally, in rapeseed plants, metazachlor was detected only in the first sampling (28 DAA) at concentrations slightly higher than the limit of quantification; when in seeds, no residues of the herbicide were detected.

Parametric Investigation of the Kinetics of Growth of Carbon-Nanotube Arrays on Iron Nanoparticles in the Process of Chemical Vapor Deposition of Hydrocarbons

NASA Astrophysics Data System (ADS)

Futko, S. I.; Shulitski, B. G.; Labunov, V. A.; Ermolaevaa, E. M.

2015-03-01

On the basis of the kinetic model of synthesis of carbon nanotubes on iron nanoparticles in the process of chemical vapor deposition of hydrocarbons, the parametric dependences of characteristics of arrays of vertically oriented nanotubes on the temperature of their synthesis, the concentration of acetylene in a reactor, and the diameter of the catalyst nanoparticles were investigated. It is shown that the maximum on the temperature dependence of the rate of growth of carbon nanotubes, detected in experiments at a temperature of ~700oC is due to the competing processes of increasing the catalytic activity of iron nanoparticles and decreasing the acetylene concentration because of the signifi cant gas-phase decomposition of acetylene in the reactor before it enters the substrate with the catalyst. Our calculations have shown that the indicated maximum arises near the transition point separating the low-temperature region where multiwall nanotubes are predominantly synthesized from the higher-temperature region of generation of single-wall nanotubes in the process of chemical vapor deposition of hydrocarbons.

Long term plant biomonitoring in the vicinity of waste incinerators in The Netherlands.

PubMed

van Dijk, Chris; van Doorn, Wim; van Alfen, Bert

2015-03-01

Since the mid-nineties new waste incineration plants have come into operation in the Netherlands. Burning of waste can result in the emission of potentially toxic compounds. Although the incineration plants must comply with strict conditions concerning emission control, public concern on the possible impact on human health and the environment still exists. Multiple year (2004-2013) biomonitoring programs were set up around three waste incinerators for early detection of possible effects of stack emissions on the quality of crops and agricultural products. The results showed that the emissions did not affect the quality of crops and cow milk. Concentrations of heavy metals, PAHs and dioxins/PCBs were generally similar to background levels and did not exceed standards for maximum allowable concentrations in foodstuffs (e.g. vegetables and cow milk). Some exceedances of the fluoride standard for cattle feed were found almost every year in the maximum deposition areas of two incinerators. Biomonitoring with leafy vegetables can be used to monitor the real impact of these emissions on agricultural crops and to communicate with all stakeholders. Copyright © 2014 Elsevier Ltd. All rights reserved.

Factors affecting occurrence and distribution of selected contaminants in ground water from selected areas in the Piedmont Aquifer System, Eastern United States, 1993-2003

USGS Publications Warehouse

Lindsey, Bruce D.; Falls, W. Fred; Ferrari, Matthew J.; Zimmerman, Tammy M.; Harned, Douglas A.; Sadorf, Eric M.; Chapman, Melinda J.

2006-01-01

Results of ground-water sampling from 255 wells and 19 springs in 11 studies done by the U.S. Geological Survey National Water-Quality Assessment (NAWQA) Program within the Piedmont Aquifer System (PAS) were analyzed to determine the factors affecting occurrence and distribution of selected contaminants. The contaminants, which were selected on the basis of potential human-health effects, included nitrate, pesticides, volatile organic compounds (VOCs), and radon.The PAS was subdivided on the basis of the general rock type of the aquifers into three areas for the study—crystalline, carbonate, and siliciclastic. The 11 studies were designed to areally represent an individual aquifer rock type and overall are representative of the PAS in their distribution; 7 studies are in the crystalline-rock aquifers, 3 studies are in the siliciclasticrock aquifers, and 1 study is in the carbonate-rock aquifers. Four of the studies were focused on land use, 1 in an agricultural area and 3 in urban areas. The remaining studies had wells representing a range of land-use types.Analysis of results of nitrate sampling indicated that in 8 of the 10 areas where nitrate concentrations were measured, median concentrations of nitrate were below 3 mg/L (milligrams per liter); 2 of the 10 areas had statistically significant higher median concentrations when compared to the other 8 areas. The agricultural land-use study in the carbonate-rock aquifer in the Lower Susquehanna River Basin had the highest median nitrate concentration (11 mg/L), and 60 percent of the wells sampled exceeded the U.S. Environmental Protection Agency (USEPA) Maximum Contaminant Level (MCL) of 10 mg/L. The major aquifer study in the crystalline-rock aquifer of the Lower Susquehanna River Basin Study Unit had the second-highest median nitrate concentration. Nitrate concentrations were positively correlated to the percentage of agricultural land use around the well, the total input of nitrogen from all sources, dissolved oxygen concentration, lithology, depth to water, and soil-matrix characteristics. A linear regression model was used to determine that increases in the percentage of agricultural land use, the input of nitrogen from all sources, and dissolved oxygen were the most significant variables affecting increased concentration of nitrate. A logistic regression model was used to determine that those same factors were the most significant variables affecting whether or not the nitrate concentration would exceed 4 mg/L.Of the analysis of samples from 253 wells and 19 springs for 47 pesticides, no sample had a pesticide concentration that exceeded any USEPA MCL. The most frequently detected pesticide was desethyl atrazine, a degradation product of atrazine; the detection frequency was 47 percent. Other frequently detected pesticides included atrazine, metolachlor, simazine, alachlor, prometon, and dieldrin. Detection frequency was affected by the analytical reporting limits; the frequency of detection was somewhat lower when all pesticides were censored to the highest common detection limit. Source factors such as agricultural land use (for agricultural herbicides), urban land use (for insecticides), and the application rate were found to have positive statistical correlations with pesticide concentration. Transport factors such as depth to water and percentage of well-drained soils, sand, or silt typically were positively correlated with higher pesticide concentrations.Sampling for VOCs was conducted in 187 wells and 19 springs that were sampled for 59 VOCs. There were 137 detections of VOCs above the common censoring limit of 0.2 µg/L. The most frequently detected VOCs were chloroform, a trihalomethane, and methyl-tert butyl ether (MTBE), a fuel oxygenate. Seventy-nine wells had at least one VOC detected. The detections were related to land use and well depth. Kendall’s tau correlations indicated a significant positive correlation between chloroform concentration and urban land use, leaking underground storage tanks, population density, and well depth. MTBE concentrations also were positively correlated to urban land use, leaking underground storage tanks, population density, and well depth.Radon was sampled at 205 sites. The subdivisions used for analysis of other contaminants were not adequate for analysis of radon because radon varies on the basis of variations in mineralogy that are not reflected by the general lithologic categories used for the rest of the studies. Concentrations of radon were highest in areas where the crystalline-rock aquifers had felsic mineralogy, and the lowest concentrations of radon were in areas where the crystalline-rocks aquifer had mafic mineralogy. Water from wells in siliciclastic-rock aquifers had concentrations of radon lower than that in the felsic crystalline-rock aquifers. More than 90 percent of the wells sampled for radon exceeded the proposed MCL of 300 pCi/L (picoCuries per liter); however, only 13 percent of those wells had concentrations in water that exceeded the alternative maximum contaminant level (AMCL), a higher level that can be used by municipalities addressing other sources of radon exposure.Overall, concentrations of constituents were related to land-use factors for nitrate, pesticides, VOCs, and to aquifer lithology for radon. None of the 47 pesticides or 59 VOCs analyzed exceeded the MCLs where those constituents were sampled. Concentrations exceeded the MCL for nitrate in 11 percent of the wells sampled. Nearly 91 percent of the wells sampled exceeded the proposed MCL for radon. Additional sampling in selected areas would improve overall understanding of the PAS and increase the possibility of creating predictive models of ground-water quality in this area.

Spectrofluorimetric determination of cefixime using terbium-danofloxacin probe

PubMed Central

Manzoori, Jamshid L.; Amjadi, Mohammad; Soltani, Naser; Jouyban, Abolghasem

2014-01-01

Objective(s): Cefixime (Cfx), is a semi-synthetic third-generation oral cephalosporin antibiotic that is prescribed for the treatment of susceptible infections. There are some procedures for the determination of Cfx in pharmaceutical formulations and biological samples. Herein a spectrofluorimetric method was proposed for Cfx determination based on the fluorescence quenching of terbium-danofloxacin (Tb3+-Dano) in the presence of Cfx. Materials and Methods: Cfx was detected based on fluorescence quenching of terbium-danofloxacin (Tb3+-Dano) in the presence of Cfx with maximum excitation and emission wavelengths at 347 nm and 545 nm, respectively. The quenched fluorescence intensity of Tb3+- Dano system is proportional to the concentration of Cfx. The optimum conditions for the determination of Cfx were studied. Results: The maximum response was achieved under optimum conditions of [Tris buffer]= 0.008 mol/l (pH 6.5), [Tb3+]=1×10-4 mol/l and [Dano]=1×10-4 mol/l. The developed method was evaluated in terms of accuracy, precision and limit of detection. The linear concentration ranges for quantification of Cfx were 8.8×10-8-8.8×10-7 mol/l and 1.1×10-7-8.8×10-7 mol/l in standard and human serum samples with the detection limits (S/N=3) of 2.8×10-8 mol/l and 3.9×10-8 mol/l, respectively. The Cfx was determined in pharmaceutical tablets and spiked serum samples and the results were satisfactory. Conclusion: This method is simple, practical and relatively interference-free for determination of Cfx in pharmaceutical tablets and serum samples. PMID:24904718

Determination of volatile organic compounds including alcohols in refill fluids and cartridges of electronic cigarettes by headspace solid-phase micro extraction and gas chromatography-mass spectrometry.

PubMed

Lim, Hyun-Hee; Shin, Ho-Sang

2017-02-01

An analytical method for the detection of 14 volatile organic compounds (VOCs) was developed to investigate VOCs in refill fluids and cartridges of electronic cigarettes (EC) using headspace solid-phase micro extraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS). In total, 14 VOCs were identified and quantified in 283 flavored liquids, 21 nicotine liquids, and 12 disposable cartridges. The detected concentration ranges of the VOCs are as follows: benzene (0.008-2.28 mg L -1 ), toluene (0.006-0.687 mg L -1 ), ethylbenzene (0.01-1.21 mg L -1 ), m-xylene (0.002-1.13 mg L -1 ), p-xylene (0.007-2.8 mg L -1 ), o-xylene (0.004-2.27 mg L -1 ), styrene (0.011-0.339 mg L -1 ), ethyl acetate (0.3-669.9 mg L -1 ), ethanol (16-38,742 mg L -1 ), methanol (66-3375 mg L -1 ), pyridine (0.077-99.7 mg L -1 ), acetylpyrazine (0.077-147 mg L -1 ), 2,3,5-trimethylpyrazine (0.008-96.8 mg L -1 ), and octamethylcyclotetrasiloxane (0.1-57.2 mg L -1 ). Benzene, toluene, ethylbenzene, m-xylene, p-xylene, and o-xylene coexisted in samples, which may have originated from the use of petrogenic hydrocarbons as an extraction solvent for flavor and nicotine from natural plants. The maximum detected concentrations of benzene, methanol, and ethanol in liquid samples were found in quantities higher than their authorized maximum limits as residual solvents in pharmaceutical products.

Distribution and stability of aflatoxin M1 during processing, ripening and storage of Telemes cheese.

PubMed

Govaris, A; Roussi, V; Koidis, P A; Botsoglou, N A

2001-05-01

Telemes cheeses were produced using milk that was artificially-contaminated with aflatoxin M1 at the levels of 0.050 and 0.100 microg/l. The cheeses produced in the two cheese-making trials were allowed to ripen for 2 months and stored for an additional 4 months to simulate commercial production of Telemes cheese. Concentrations of aflatoxin M1 in whey, curd, brine, and the produced cheeses were determined at intervals by liquid chromatography and fluorometric detection coupled with immunoaffinity column extraction. Concentrations of aflatoxin M1 in the produced curds were found to be 3.9 and 4.4 times higher than those in milk, whereas concentrations in whey were lower than those in curd and milk. Aflatoxin M1 was present in cheese at higher concentrations at the beginning than at the end of the ripening/storage period, and it declined to concentrations 2.7 and 3.4 times higher than those initially present in milk by the end of the sixth month of storage. Concentrations of aflatoxin M1 in brine started low and increased by the end of the ripening/storage period but only a portion of the amounts of aflatoxin M1 lost from cheese was found in the brine. Results showed that Telemes cheeses produced from milk containing aflatoxin M1 at a concentration close to either the maximum acceptable level of 0.05 microg/l set by the European union (EU) or at double this value, will contain the toxin at a level that is much lower or slightly higher, respectively, than the maximum acceptable level of 0.250 microg of aflatoxin M1/kg cheese set by some countries.

Biological and chemical analysis of the toxic potency of pesticides in rainwater.

PubMed

Hamers, T; Smit, M G; Murk, A J; Koeman, J H

2001-11-01

A newly developed method for measuring the integrated esterase inhibiting potency of rainwater samples was applied in practice, and the results are compared to the toxic potency calculated from concentrations of 31 organophosphate (OP) and carbamate pesticides, out of a total of 66 chemically analyzed pesticides. In addition, the general toxic potency of the rainwater samples was evaluated in a microtiter luminescence assay with Vibrio fischeri bacteria. Rainwater samples were collected over four consecutive 14-day periods in both open and wet-only samplers. The esterase inhibiting potency of the open rainwater samples (expressed as ng dichlorvos-equivalents/l) corresponded well with the chemical analyses of the rainwater samples collected by both types of samplers (r = 0.83-0.86). By far, the highest esterase inhibiting potency was found in a sample collected in an area with intense horticultural activities in June, and was attributed to high concentrations of dichlorvos, mevinphos, pirimiphos-methyl and methiocarb. The esterase inhibiting potency of this sample was equivalent to a dichlorvos concentration of 1380 ng/l in the rainwater, which is almost 2000 times higher than the maximum permissible concentration (MPC) of dichlorvos set for surface water in Netherlands. Maximum individual concentrations of dichlorvos and pirimiphos-methyl even exceeded the EC50 for Daphnia, suggesting that pesticides in rainwater pose a risk for aquatic organisms. Not all responses of the luminescence-assay for general toxicity could be explained by the analyzed pesticide concentrations. The bio-assays enable a direct assessment the toxic potency of all individual compounds present in the complex mixture of rainwater pollutants, even if they are unknown or present at concentrations below the detection limit. Therefore, they are valuable tools for prescreening and hazard characterization purposes.

Development of a Simple and Rapid Method to Measure the Free Fraction of Tacrolimus in Plasma Using Ultrafiltration and LC-MS/MS.

PubMed

Stienstra, Nicolaas A; Sikma, Maaike A; van Dapperen, Anouk L; de Lange, Dylan W; van Maarseveen, Erik M

2016-12-01

Tacrolimus is an immunosuppressant mainly used in the prophylaxis of solid organ transplant rejection. Therapeutic drug monitoring of tacrolimus is essential for avoiding toxicity related to overexposure and transplant rejection from underexposure. Previous studies suggest that unbound tacrolimus concentrations in the plasma may serve as a better predictor of tacrolimus-associated nephrotoxicity and neurotoxicity compared to tacrolimus concentration in whole blood. Monitoring the plasma concentrations of unbound tacrolimus might be of interest in preventing tacrolimus-related toxicity. Therefore, the aim was to develop a method for the measurement of total and unbound tacrolimus concentrations in plasma. The sample preparation for the determination of the plasma concentrations of unbound tacrolimus consisted of an easy-to-use ultrafiltration method followed by solid-phase extraction. To determine the total concentration of tacrolimus in plasma, a simple method based on protein precipitation was developed. The extracts were injected into a Thermo Scientific HyPurity C18 column using gradient elution. The analytes were detected by liquid chromatography-tandem mass spectrometry with positive ionization. The method was validated over a linear range of 1.00-200 ng/L for unbound tacrolimus concentrations in plasma and 100-3200 ng/L for total plasma concentrations. The lower limit of quantification was 1.00 ng/L in ultrafiltrate and 100 ng/L in plasma. The inaccuracy and imprecision for the determination of unbound tacrolimus concentrations in ultrafiltrate and plasma showed a maximum coefficients of variation (CV) of 11.7% and a maximum bias of 3.8%. A rapid and easy method based on ultrafiltration and liquid chromatography-tandem mass spectrometry was established to measure the total and unbound tacrolimus concentrations in plasma. This method can facilitate further investigations on the relationship between plasma concentrations of unbound tacrolimus and clinical outcomes in transplant recipients.

Comparison of concentrations and profiles of polycyclic aromatic hydrocarbon metabolites in bile of fishes from offshore oil platforms and natural reefs along the California coast

USGS Publications Warehouse

Gale, Robert W.; Tanner, Michael J.; Love, Milton S.; Nishimoto, Mary M.; Schroeder, Donna M.

2012-01-01

To determine the environmental consequences of decommissioning offshore oil platforms on local and regional fish populations, contaminant loads in reproducing adults were investigated at seven platform sites and adjacent, natural sites. Specimens of three species (Pacific sanddab, Citharichthys sordidus; kelp rockfish, Sebastes atrovirens; and kelp bass, Paralabrax clathratus) residing at platforms and representing the regional background within the Santa Barbara Channel and within the San Pedro Basin were collected. Some of the most important contaminant classes related to oil operations are polycyclic aromatic hydrocarbons (PAHs) because of their potential toxicity and carcinogenicity. However, acute exposure cannot be related directly to PAH tissue concentrations because of rapid metabolism of the parent chemicals in fish; therefore, PAH metabolites in bile were measured, targeting free hydroxylated PAHs (OH-PAHs) liberated by enzymatic hydrolysis of the bound PAH glucuronides and sulfates. An ion-pairing method was developed for confirmatory analysis that targeted PAH glucuronides and sulfates. Concentrations of hydroxylated PAHs in all samples (76 fish from platforms and 64 fish from natural sites) were low, ranging from less than the limits of detection (5 to 120 nanograms per milliliter bile; 0.03 to 42 nanograms per milligram protein) to a maximum of 320 nanograms per milliliter bile (32 nanograms per milligram protein). A previously proposed dosimeter of PAH exposure in fish, 1-hydroxypyrene, was not detected at any platform site. Low concentrations of 1-hydroxypyrene were detected in 3 of 12 kelp rockfish collected from a natural reef site off Santa Barbara. The most prevalent OH-PAH, 2-hydroxyfluorene, was detected at low concentrations in seven fish of various species; of these, four were from two of the seven platform sites. The greatest concentrations of 2-hydroxyfluorene were found in three fish of various species from Platform Holly and were only about threefold above low, yet quantifiable, concentrations found in three fish from Horseshoe Reef, East Anacapa Island, and Coche Point natural sites; the mean concentrations among all sampling sites were not measurably different.

Changes During Recovery from Sodium Deficiency in Atriplex

PubMed Central

Brownell, P. F.; Jackman, Margaret E.

1966-01-01

Although the concentration of sodium in leaves of Atriplex plants increased rapidly after receiving sodium, no growth response was detectable for about 6 days. It was found that respiration rate increased to its maximum within 3 days. Chlorophyll content also increased from an early stage, whereas the concentrations of sugars and starch did not increase, and ratios of soluble to total nitrogen did not decrease until later. The respiratory response appears to be specific to sodium as different salts of sodium caused similar responses, and no other univalent cation substituted for sodium. In addition, both growth response and respiration rate tended towards their maxima with the same concentration of applied sodium. The rate of anaerobic CO2 production increased when sodium was fed to leaves, suggesting that the effect of sodium is in the glycolytic sequence. PMID:16656296

Hydrology and water-quality at the Weldon Spring radioactive waste-disposal sites, St Charles County, Missouri

USGS Publications Warehouse

Kleeschulte, M.J.; Emmett, L.F.

1987-01-01

Water samples from five monitoring wells adjacent to raffinate pits storing low-level radioactive waste contained concentrations of nitrate as nitrogen ranging from 53 to 990 milligrams per liter. Most samples also had maximum concentrations of calcium (900 milligrams per liter), sodium (340 milligrams per liter), sulfate (320 milligrams per liter), lithium (1,700 micrograms), strontium (1,900 micrograms per liter), and uranium (86 micrograms per liter). The raffinate pits also had large concentrations of these constituents. A water balance made on the raffinate pits indicated a 0.04 to 0.08 inch per day decrease in the water level that cannot be attributed to meterological conditions. These data and seismically-detected areas of saturated overburden beneath one raffinate pit and possibly adjacent to three other pits indicate leakage from the pits. (USGS)

Molecular compositions and decadal trends of dicarboxylic acids, ketoacids, α-dicarbonyls in the marine aerosols from Chichi-Jima Island in the western North Pacific

NASA Astrophysics Data System (ADS)

Kawamura, K.; Tachibana, E.

2010-12-01

A rapid industrial development in China and East Asian countries for last two decades may have seriously changed the air quality of the North Pacific. To better understand a long-term atmospheric changes of organic aerosols in the western North Pacific, we collected marine aerosol samples on weekly basis at a remote island, Chichijima (27°04'E; 142°13'N) in 2001-2010. The island is located in the boundary of westerly and easterly wind regimes. The aerosol samples were analyzed for dicarboxylic acids, ketoacids and α-dicarbonyls employing butyl ester derivatization followed by GC determination, together with total carbon (TC) and water-soluble organic carbon (WSOC). Homologous series of saturated diacids (C2-C11) were detected with a predominance of oxalic (C2) acid followed by malonic (C3) and succinic (C4) acids. Unsaturated diacids, including maleic (M), fumaric (F), phthalic, and iso-/tere-phthalic acids, were also detected together with ketoacids and α-dicarbonyls. Concentrations of total diacids fluctuated significantly in a range of 10-600 ngm-3 with winter/spring maximum and summer minimum. The maximum was explained by a combination of enhanced emissions of polluted aerosols and their precursors in Asia and enhanced atmospheric transport to the North Pacific due to the intensified westerly winds in winter/spring. Concentration ratios of C3 to C4 diacid (range 0.2-28, av. 2.8) showed a maximum during summer, indicating more oxidation of longer-chain diacids to shorter ones. Azelaic acid (C9) that is a specific photo-oxidation product of unsaturated fatty acid such as oleic acid showed a sharp increase relative to other diacids in summer, suggesting enhanced sea-to-air emission of unsaturated fatty acids followed by photochemical oxidation during summer. On the other hand, M/F ratios (range 0-8.7, av. 1.1) significantly decreased from winter to summer due to photochemical cis-to-trans isomerization. We also discuss decadal trends in the concentrations of diacids and related compounds as well as TC and WSOC, and their compositions and relative abundances.

Release of serum S-100β protein and neuron-specific enolase after off-pump coronary artery bypass grafting with and without intracranial and cervical artery stenosis.

PubMed

Tamura, Atsushi; Imamaki, Mizuho; Shimura, Hitoshi; Niitsuma, Yuriko; Miyazaki, Masaru

2011-01-01

The aim of this study was to quantify the amount of brain damage suffered by patients who underwent off-pump coronary artery bypass grafting (OPCAB) in which S-100β protein and neuron-specific enolase were used. Thirty-four patients undergoing scheduled OPCAB were enrolled in the study. The patients were divided into two groups according to the results of their magnetic resonance angiography (MRA) and cervical ultrasonography: 13 patients had cervical or intracranial arterial stenosis (Group A), and 21 patients did not (Group B). Blood samples were collected from the arterial catheters immediately before surgery, upon arrival to the intensive care unit, and 6 and 24 hours after surgery. In blood samples collected from patients upon arrival to the intensive care unit, the maximum concentration of serum s-100β protein in Group A was significantly higher than that of Group B (p = 0.029). Though patients in Group A tended to have higher maximum neuron-specific enolase (NSE) concentrations, there were no significant differences in NSE concentrations at any point between the two groups. Our findings show a correlation between the stenosis detected by MRA or cervical ultrasonography and brain damage after OPCAB.

Bacterial growth kinetics in ACD-A apheresis platelets: comparison of plasma and PAS III storage.

PubMed

Dumont, Larry J; Wood, Tammara A; Housman, Molly; Herschel, Louise; Brantigan, Barbara; Heber, Cheryl; Houghton, Jaime

2011-05-01

Our objective was to determine the growth kinetics of bacteria in leukoreduced apheresis platelets (LR-AP) in a platelet (PLT) additive solution (PAS; InterSol, Fenwal, Inc.) compared to LR-AP stored in plasma. Hyperconcentrated, double-dose LR-AP were collected from healthy donors with a separator (AMICUS, Fenwal, Inc.). LR-AP were evenly divided, InterSol was added to half (65% InterSol:35% plasma [PAS]), and PLTs in autologous plasma were used for a paired control (PL). Bacteria were inoculated into each LR-AP PAS/PL pair (0.5-1.6 colony-forming units [CFUs]/mL), and bacterial growth was followed for up to 7 days. Time to the end of the lag phase, doubling times, maximum concentration (conc-max), and time to maximum concentration (time-max) were estimated. Streptococcus viridans did not grow to detectable levels in either PAS or PL units. The other bacteria had no significant overall difference in the conc-max (p = 0.47) or time-max (p = 0.7) between PL and PAS LR-AP; PL had a 0.14 hours faster doubling rate (p = 0.023); and PAS had a 4.7 hours shorter lag time (p = 0.016). We observed that five index organisms will grow in LR-AP stored in a 35%:65% ratio of plasma to InterSol where initial bacterial concentrations are 0.5 to 1.6 CFUs/mL. The more rapid initiation of log-phase growth for bacteria within a PAS storage environment resulted in a bacterial concentration up to 4 logs higher in the PAS units compared to the plasma units at 24 hours, but with no difference in the conc-max. This may present an early bacterial detection advantage for PAS-stored PLTs. © 2010 American Association of Blood Banks.

Screening of 1300 organic micro-pollutants in groundwater from Beijing and Tianjin, North China.

PubMed

Kong, Lingxiao; Kadokami, Kiwao; Duong, Hanh Thi; Chau, Hong Thi Cam

2016-12-01

Groundwater contamination in China has become a growing public concern because of the country's rapid economic development and dramatically increasing fresh water demand. However, there is little information available on groundwater quality, particularly with respect to trace organic micro-pollutants contamination. This study was undertaken to investigate the occurrence of 1300 pollutants at 27 groundwater sites in Beijing and Tianjin, North China. Seventy-eight chemicals (6% of the targeted compounds) were detected in at least one sampling point; observed chemicals included polycyclic aromatic hydrocarbons (PAHs), pesticides, plasticizers, antioxidants, pharmaceuticals and other emerging compounds. Chemicals with a frequency of detection over 70% were 2-ethyl-1-hexanol (median concentration 152 ng L -1 ), benzyl alcohol (582 ng L -1 ), 2-phenoxy-ethanol (129 ng L -1 ), acetophenone (74 ng L -1 ), pentamethylbenzene (51 ng L -1 ), nitrobenzene (40 ng L -1 ) and dimethyl phthalate (64 ng L -1 ). Pesticides with concentrations exceeding the EU maximum residual limits (MRL) of 0.1 μg L -1 were 1,4-dichlorobenzene, oxadixyl, diflubenzuron, carbendazim, diuron, and the E and Z isomers of dimethomorph. Naphthalene and its 7 alkylated derivatives were widely observed at maximum concentration up to 30 μg L -1 , which, although high, is still below the Australian drinking water guidelines of 70 μg L -1 . The risk assessment indicated there is no human health risk through the oral consumption from most wells, although there were four wells in which total seven compounds were found at the concentrations with a potential adverse health effects. This work provides a wide reconnaissance on broad spectrum of organic micro-contaminants in groundwater in North China. Copyright © 2016. Published by Elsevier Ltd.

Long-term trend of dicarboxylic acids, ketoacids and dicarbonyls in the marine aerosols over the western North Pacific in 2001-2006

NASA Astrophysics Data System (ADS)

Kawamura, K.; Tachibana, E.; Mochida, M.

2006-12-01

To understand a long-range atmospheric transport of water-soluble organics in the western North Pacific, remote marine aerosols were collected on weekly basis at a subtropical island (Chichijima, 142E; 27N) from 2001 to 2006 using a high volume air sampler and pre-combusted quartz filter. The island is located in the boundary of westerly and trade wind regimes. The aerosols were analyzed for dicarboxylic acids, ketoacids and dicarbonyls employing butyl ester derivatization followed by GC determination. Homologous saturated diacids (C2-C11) were detected with a predominance of oxalic (C2) acid followed by malonic (C3) and succinic (C4) acids as well as unsaturated diacids, including maleic (M), fumaric (F), phthalic acids. Ketoacids and dicarbonyls were also detected. Concentrations of total diacids fluctuated significantly in a range of 10-600 ngm-3 with winter/spring maximum and summer minimum. The winter/spring maximum can be explained by a combinattion of enhanced emissions of polluted aerosols and their precursors in Asia and the intensified westerlies over the North Pacific in the season. Seasonal trends of the molecular compositions were also found. For example, concentration ratios of C3 to C4 acid showed a maximum in summer, indicating more oxidation of longer-chain diacids to shorter ones. M/F ratios increased from summer to winter as a result of photochemically-induced isomerization of cis and trans configuration of unsaturated diacids. On the other hand, azelaic acid (C9) relative to other diacids showed a sharp increase in summer. Because C9 is a specific photo-oxidation product of unsaturated fatty acid such as oleic acid, this demonstrates an enhanced sea-to- air emission of unsaturated fatty acids in summer followed by photochemical oxidation. Long-term trends of diacids and related compounds in the aerosols will be discussed for 2001 to 2006. The results will also be compared with those obtained at the same site for 1990 to 1993 to detect long-term changes in the organic aerosol compositions that might be happened over the western North Pacific due to the enhanced human activity in East Asia.

Natural postharvest aflatoxin occurrence in food legumes in the smallholder farming sector of Zimbabwe.

PubMed

Maringe, David Tinayeshe; Chidewe, Cathrine; Benhura, Mudadi Albert; Mvumi, Brighton Marimanzi; Murashiki, Tatenda Clive; Dembedza, Mavis Precious; Siziba, Lucia; Nyanga, Loveness Kuziwa

2017-03-01

Aflatoxins, mainly produced by Aspergillus flavus and Aspergillus parasiticus, are highly toxic and may lead to health problems such as liver cancer. Exposure to aflatoxins may result from ingestion of contaminated foods. Levels of AFB 1 , AFB 2 , AFG 1 and AFG 2 in samples of groundnuts (Arachis hypogaea), beans (Phaseolus vulgaris), cowpeas (Vigna unguiculata) and bambara nuts (Vigna subterranean) grown by smallholder farmers in Shamva and Makoni districts, Zimbabwe, were determined at harvesting, using high performance liquid chromatography after immunoaffinity clean-up. Aflatoxins were detected in 12.5% of groundnut samples with concentrations ranging up to 175.9 µg/kg. Aflatoxins were present in 4.3% of the cowpea samples with concentrations ranging from 1.4 to 103.4 µg/kg. Due to alarming levels of aflatoxins detected in legumes versus maximum permissible levels, there is a need to assist smallholder farmers to develop harvest control strategies to reduce contamination of aflatoxins in legumes.

Safe apples for baby-food production: survey of pesticide treatment regimes leaving minimum residues.

PubMed

Ticha, Jana; Hajslova, Jana; Kovalczuk, Tomas; Jech, Martin; Honzicek, Jiri; Kocourek, Vladimir; Lansky, Miroslav; Kloutvorova, Jana; Falta, Vladan

2007-06-01

A total of 19 pesticide preparations were used according to agricultural practice in six trials in apple orchards. Using gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS), premature Golden Delicious apples collected 64, 50, 36 days before harvest and mature fruit were examined for residues of active ingredients. No residues of triflumuron, triazamate, chlorpyrifos, etofenprox, fenoxycarb, kresoxim-methyl, cyprodinyl, difenoconazole or thiram were detected in the first sampling. Also, the levels of chlorpyrifos-methyl, penconazole, tebuconazole and tolylfluanid dropped during the pre-harvest interval. Detectable residues of pyridaben, thiacloprid, trifloxystrobin and tetraconazole in harvested fruits were below 0.01 mg kg(-1), which is the maximum concentration of residues acceptable by baby-food producers in any raw material. The only residues exceeding this concentration were captan and teflubenzuron. Based on the data, farmers can choose pesticides for optimal treatment of plants, while enabling growth of a safe crop suitable for baby-food production.

Determination of fluoroquinolones in chicken feces - a new liquid-liquid extraction method combined with LC-MS/MS.

PubMed

Janusch, Franziska; Scherz, Gesine; Mohring, Siegrun A I; Hamscher, Gerd

2014-11-01

The application of antibiotics including fluoroquinolones to farming animals is widespread and may lead to the development of antibiotic resistance and other environmental effects. To calculate environmental loads and for a proper risk assessment it is necessary to determine the antibiotic concentration in feces. Therefore, a new liquid-liquid extraction method combined with HPLC-MS/MS for the detection of marbofloxacin, ciprofloxacin, enrofloxacin and difloxacin in chicken feces was developed. Recoveries ranged from 51.0% to 83.5%. LOQs were between 0.10 and 1.09μg/kg. Feces of chickens treated with an enrofloxacin dosage of 10mg/kg bodyweight revealed maximum enrofloxacin and ciprofloxacin concentrations of 61.3 and 18.8mg/kg. Both antibiotics could be detected in feces up to two days after the last application in notable amounts (∼1mg/kg). Thus, feces of recently medicated chickens should not be used as a fertilizer without any further processing. Copyright © 2014 Elsevier B.V. All rights reserved.

Ground-Water Quality Data in the Coachella Valley Study Unit, 2007: Results from the California GAMA Program

USGS Publications Warehouse

Goldrath, Dara A.; Wright, Michael T.; Belitz, Kenneth

2009-01-01

Ground-water quality in the approximately 820 square-mile Coachella Valley Study Unit (COA) was investigated during February and March 2007 as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Project was developed in response to the Groundwater Quality Monitoring Act of 2001, and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The study was designed to provide a spatially unbiased assessment of raw ground water used for public-water supplies within the Coachella Valley, and to facilitate statistically consistent comparisons of ground-water quality throughout California. Samples were collected from 35 wells in Riverside County. Nineteen of the wells were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study unit (grid wells). Sixteen additional wells were sampled to evaluate changes in water chemistry along selected ground-water flow paths, examine land use effects on ground-water quality, and to collect water-quality data in areas where little exists. These wells were referred to as 'understanding wells'. The ground-water samples were analyzed for a large number of organic constituents (volatile organic compounds [VOC], pesticides and pesticide degradates, pharmaceutical compounds, and potential wastewater-indicator compounds), constituents of special interest (perchlorate and 1,2,3-trichloropropane [1,2,3-TCP]), naturally occurring inorganic constituents (nutrients, major and minor ions, and trace elements), radioactive constituents, and microbial indicators. Naturally occurring isotopes (uranium, tritium, carbon-14, and stable isotopes of hydrogen, oxygen, and boron), and dissolved noble gases (the last in collaboration with Lawrence Livermore National Laboratory) also were measured to help identify the source and age of the sampled ground water. A quality-control sample (blank, replicate, or matrix spike) was collected at approximately one quarter of the wells, and the results for these samples were used to evaluate the quality of the data for the ground-water samples. Assessment of the quality-control information resulted in V-coding less than 0.1 percent of the data collected. This study did not attempt to evaluate the quality of water delivered to consumers; after withdrawal from the ground, water typically is treated, disinfected, and (or) blended with other waters to maintain acceptable water quality. Regulatory thresholds apply to treated water that is supplied to the consumer, not to raw ground water. However, to provide some context for the results, concentrations of constituents measured in the raw ground water were compared with health-based thresholds established by the U.S. Environmental Protection Agency (USEPA) and the California Department of Public Health (CDPH) and thresholds established for aesthetic purposes (secondary maximum contaminant levels, SMCL-CA) by CDPH. Most constituents detected in ground-water samples were at concentrations below drinking-water thresholds. Volatile organic compounds, pesticides, and pesticide degradates were detected in less than one-third of the grid well samples collected. All VOC and pesticide concentrations measured were below health-based thresholds. Potential waste-water indicators were detected in less than half of the wells sampled, and no detections were above health-based thresholds. Perchlorate was detected in seven grid wells; concentrations from two wells were above the CDPH maximum contaminant level (MCL-CA). Most detections of trace elements in samples collected from COA Study Unit wells were below water-quality thresholds. Exceptions include five samples of arsenic that were above the USEPA maximum contaminant level (MCL-US), two detections of boron above the CDPH notification level (NL-CA), and two detections of mol

Effectiveness of an alluvial wetland on improving ground-water quality in a municipal well field, Cedar Rapids, Iowa, 1998-2006

USGS Publications Warehouse

Schnoebelen, Douglas J.

2008-01-01

An alluvial wetland proved useful in improving water quality. Samples from observation wells completed in the alluvial wetland near the municipal well field had nitrate concentrations that were four to six times lower when compared to river or upland sites; however, iron and manganese concentrations in samples from observation wells in the wetland areas were an order of magnitude higher when compared to the river or an upgradient well. Biological and chemical reduction processes were determined to mobilize inorganic constituents in accordance with physical chemistry principles. Generally, selected pesticides and two pesticide degradates of atrazine that were sampled for in alluvial wetland wells remained relatively unchanged, and indicated only a slight decrease in concentration compared to the Cedar River water samples. Pesticides were not detected above regulatory limits in any of the observation wells; however, one sample from the Cedar River had an atrazine detection at 4.5 micrograms per liter, which is above the maximum contaminant level of 3.0 micrograms per liter for drinking-water regulations for that compound. Results indicate that alluvial wetlands may provide substantial reductions of nitrate concentrations in ground water, and may be a useful strategy for the reduction of nitrate for municipal wells. Results for reducing pesticides were less dramatic than for nitrate, as pesticide concentrations were reduced slightly from the river to the wetland.

Ultrasonically Modified Amended-Cloud Point Extraction for Simultaneous Pre-Concentration of Neonicotinoid Insecticide Residues.

PubMed

Kachangoon, Rawikan; Vichapong, Jitlada; Burakham, Rodjana; Santaladchaiyakit, Yanawath; Srijaranai, Supalax

2018-05-12

An effective pre-concentration method, namely amended-cloud point extraction (CPE), has been developed for the extraction and pre-concentration of neonicotinoid insecticide residues. The studied analytes including clothianidin, imidacloprid, acetamiprid, thiamethoxam and thiacloprid were chosen as a model compound. The amended-CPE procedure included two cloud point processes. Triton™ X-114 was used to extract neonicotinoid residues into the surfactant-rich phase and then the analytes were transferred into an alkaline solution with the help of ultrasound energy. The extracts were then analyzed by high-performance liquid chromatography (HPLC) coupled with a monolithic column. Several factors influencing the extraction efficiency were studied such as kind and concentration of surfactant, type and content of salts, kind and concentration of back extraction agent, and incubation temperature and time. Enrichment factors (EFs) were found in the range of 20⁻333 folds. The limits of detection of the studied neonicotinoids were in the range of 0.0003⁻0.002 µg mL −1 which are below the maximum residue limits (MRLs) established by the European Union (EU). Good repeatability was obtained with relative standard deviations lower than 1.92% and 4.54% for retention time ( t R ) and peak area, respectively. The developed extraction method was successfully applied for the analysis of water samples. No detectable residues of neonicotinoids in the studied samples were found.

Reconnaissance of selected PPCP compounds in Costa Rican surface waters.

PubMed

Spongberg, Alison L; Witter, Jason D; Acuña, Jenaro; Vargas, José; Murillo, Manuel; Umaña, Gerardo; Gómez, Eddy; Perez, Greivin

2011-12-15

Eighty-six water samples were collected in early 2009 from Costa Rican surface water and coastal locations for the analysis of 34 pharmaceutical and personal care product compounds (PPCPs). Sampling sites included areas receiving treated and untreated wastewaters, and urban and rural runoff. PPCPs were analyzed using a combination of solid phase extraction and liquid chromatography tandem mass spectrometry. The five most frequently detected compounds were doxycycline (77%), sulfadimethoxine (43%), salicylic acid (41%), triclosan (34%) and caffeine (29%). Caffeine had the maximum concentration of 1.1 mg L(-1), possibly due to coffee bean production facilities upstream. Other compounds found in high concentrations include: doxycycline (74 μg L(-1)), ibuprofen (37 μg L(-1)), gemfibrozil (17 μg L(-1)), acetominophen (13 μg L(-1)) and ketoprofen (10 μg L(-1)). The wastewater effluent collected from an oxidation pond had similar detection and concentrations of compounds compared to other studies reported in the literature. Waters receiving runoff from a nearby hospital showed higher concentrations than other areas for many PPCPs. Both caffeine and carbamazepine were found in low frequency compared to other studies, likely due to enhanced degradation and low usage, respectively. Overall concentrations of PPCPs in surface waters of Costa Rica are inline with currently reported occurrence data from around the world, with the exception of doxycycline. Published by Elsevier Ltd.

Occurrence and transport of acetochlor in streams of the Mississippi River Basin

USGS Publications Warehouse

Clark, G.M.; Goolsby, D.A.

1999-01-01

The herbicide acetochlor [2-chloro-N-(ethoxymethyl)-N-(2-ethyl-6- methylphenyl) acetamide] was first used on corn (Zea mays L.) in the USA during the growing season of 1994. By 1996, it was the third most heavily used corn herbicide in the midwestern USA. During the growing season of 1997, 78% of 375 samples collected at 32 stream sites in the Mississippi River Basin contained detectable concentrations of acetochlor. However, concentrations in only 2% of the samples exceeded 2 ??g/L, the maximum annual average concentration allowable in public water supplies derived primarily from surface water. The largest acetochlor concentrations were detected in streams draining basins in parts of Illinois, Indiana, and Iowa. The median concentration of acetochlor in streams was about 10% that of atrazine (6- chloro-N-ethyl-N-isopropyl-1,3,5-triazine-2,4-diamine), about 25% that of metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl) acetamide], about 50% that of cyanazine [2-[[4-chloro-6-(ethylamino)-1,3,5- triazin-2-yl]amino]-2-methylpropionitrile], and about threefold that of alachlor [2-chloro-2',6'-diethyl-N-(methoxymethyl) acetanilide]. Load estimates indicate that, during the growing season of 1997, agricultural subbasins draining areas of Illinois, Indiana, and Iowa contributed about 37000 kg, or 74%, of the 50 000 kg of acetochlor measured in streams of the Mississippi River Basin.

Analysis of ground-water flow in the Madison aquifer using fluorescent dyes injected in Spring Creek and Rapid Creek near Rapid City, South Dakota, 2003-04

USGS Publications Warehouse

Putnam, Larry D.; Long, Andrew J.

2007-01-01

The Madison aquifer, which contains fractures and solution openings in the Madison Limestone, is used extensively for water supplies for the city of Rapid City and other suburban communities in the Rapid City, S. Dak., area. The 48 square-mile study area includes the west-central and southwest parts of Rapid City and the outcrops of the Madison Limestone extending from south of Spring Creek to north of Rapid Creek. Recharge to the Madison Limestone occurs when streams lose flow as they cross the outcrop. The maximum net loss rate for Spring and Rapid Creek loss zones are 21 and 10 cubic feet per second (ft3/s), respectively. During 2003 and 2004, fluorescent dyes were injected in the Spring and Rapid Creek loss zones to estimate approximate locations of preferential flow paths in the Madison aquifer and to measure the response and transit times at wells and springs. Four injections of about 2 kilograms of fluorescein dye were made in the Spring Creek loss zone during 2003 (sites S1, S2, and S3) and 2004 (site S4). Injection at site S1 was made in streamflow just upstream from the loss zone over a 12-hour period when streamflow was about equal to the maximum loss rate. Injections at sites S2, S3, and S4 were made in specific swallow holes located in the Spring Creek loss zone. Injection at site R1 in 2004 of 3.5 kilograms of Rhodamine WT dye was made in streamflow just upstream from the Rapid Creek loss zone over about a 28-hour period. Selected combinations of 27 wells, 6 springs, and 3 stream sites were monitored with discrete samples following the injections. For injections at sites S1-S3, when Spring Creek streamflow was greater than or equal to 20 ft3/s, fluorescein was detected in samples from five wells that were located as much as about 2 miles from the loss zone. Time to first arrival (injection at site S1) ranged from less than 1 to less than 10 days. The maximum fluorescein concentration (injection at site S1) of 120 micrograms per liter (ug/L) at well CO, which is located adjacent to the loss zone, was similar to the concentration in the stream. Fluorescein arrived at well NON (injection at site S1), which is located about 2 miles northeast of the loss zone, within about 1.6 days, and the maximum concentration was 44 ug/L. For injection at site S4, when streamflow was about 12 ft3/s, fluorescein was detected in samples from six wells and time to first arrival ranged from 0.2 to 16 days. Following injection at site S4 in 2004, the length of time that dye remained in the capture zone of well NON, which is located approximately 2 miles from the loss zone, was almost an order of magnitude greater than in 2003. For injection at site R1, Rhodamine WT was detected at well DRU and spring TI-SP with time to first arrival of about 0.5 and 1.1 days and maximum concentrations of 6.2 and 0.91 ug/L, respectively. Well DRU and spring TI-SP are located near the center of the Rapid Creek loss zone where the creek has a large meander. Measurable concentrations were observed for spring TI-SP as many as 109 days after the dye injection. The direction of a conduit flow path in the Spring Creek area was to the northeast with ground-water velocities that ranged from 770 to 6,500 feet per day. In the Rapid Creek loss zone, a conduit flow path east of the loss zone was not evident from the dye injection.

Retrospective evaluation of the effects of administration of tetrastarch (hydroxyethyl starch 130/0.4) on plasma creatinine concentration in dogs (2010-2013): 201 dogs.

PubMed

Yozova, Ivayla D; Howard, Judith; Adamik, Katja-Nicole

2016-07-01

To determine changes in creatinine concentrations following the administration of 6% tetrastarch (hydroxyethyl starch [HES] 130/0.4) compared to crystalloids (CRYSs) in critically ill dogs. Retrospective case series (2010-2013). University teaching hospital. Two hundred and one dogs admitted to the intensive care unit with initial plasma creatinine concentrations not exceeding laboratory reference intervals (52-117 μmol/L [0.6-1.3 mg/dL]) and receiving either CRYSs alone (CRYS group, n = 115) or HES with or without CRYSs (HES group, n = 86) for at least 24 hours. None. Creatinine concentrations at admission to the intensive care unit (T0), and 2-13 days (T1) and 2-12 weeks (T2) after initiation of fluid therapy were analyzed. Creatinine concentrations were analyzed as absolute values and as the maximum percentage change from T0 to T1 (T1max%) and from T0 to T2 (T2max%), respectively. Creatinine concentrations were available for 192 dogs during T1 and 37 dogs during T2. The median cumulative dose of HES was 86 mL/kg (range, 12-336 mL/kg). No difference was detected between the groups for age, gender, body weight, and length of hospitalization. Outcome was significantly different between the HES (66% survived) and the CRYS (87% survived) groups (P = 0.014). No significant difference was detected between groups for creatinine concentrations at T0, T1, T2, T1max%, or T2max%. No significant difference was detected between the groups for T1max% creatinine in dogs subclassified as having systemic inflammatory response syndrome or sepsis. HES administration in this canine population did not result in increased creatinine concentrations compared to administration of CRYSs. Further studies are needed to establish the safety of HES in critically ill dogs. © Veterinary Emergency and Critical Care Society 2016.

Condensation nucleation light scattering detection with ion chromatography for direct determination of glyphosate and its metabolite in water.

PubMed

You, Jing; Koropchak, John A

2003-03-14

An ion chromatography-condensation nucleation light scattering detection (IC-CNLSD) method was successfully used to directly analyze glyphosate, a polar pesticide, and aminomethylphosaphonic acid, the major metabolite of glyphosate, in water without need of pre-treatment or derivatization. CNLSD gave a LOD of 53 ng/ml for glyphosate, which is much lower than the maximum contaminant level of 700 ng/ml for drinking water issued by the US Environmental Protection Agency. Spiked analytes in different matrixes were tested. A diluted commercial herbicide containing glyphosate was also evaluated. Compared to other reported methods, the IC-CNLSD method has no need of sample derivatization, pre-concentration, and mobile phase conductivity suppression. It is simple, fast and inexpensive. IC-CNLSD is an ideal direct detection technique for such pesticides without chromophores or fluorophores.

Inner filter effect and the onset of concentration dependent red shift of synchronous fluorescence spectra.

PubMed

Tarai, Madhumita; Mishra, Ashok Kumar

2016-10-12

The phenomenon of concentration dependent red shift, often observed in synchronous fluorescence spectra (SFS) of monofluorophoric as well as multifluorophoric systems at high chromophore concentrations, is known to have good analytical advantages. This was previously understood in terms of large inner filter effect (IFE) through the introduction of a derived absorption spectral profile that closely corresponds to the SFS profile. Using representative monofluorophoric and multifluorophoric systems, it is now explained how the SF spectral maximum changes with concentration of the fluorophore. For dilute solutions of monofluorophores the maximum is unchanged as expected. It is shown here that the onset of red shift of SFS maximum of both the mono as well as the multifluorophoric systems must occur at the derived absorption spectral parameter value of 0.32 that corresponds to the absorbance value of 0.87. This value is unique irrespective of the nature of the fluorophore under study. For monofluorophoric systems, the wavelength of derived absorption spectral maximum and the wavelength of synchronous fluorescence spectral maximum closely correspond with each other in the entire concentration range. In contrast, for multifluorophoric systems like diesel and aqueous humic acid, large deviations were noted that could be explained as to be due to the presence of non-fluorescing chromophores in the system. This work bridges the entire fluorophore concentration range over which the red shift of SFS maximum sets in; and in the process it establishes the importance of the derived absorption spectral parameter in understanding the phenomenon of concentration dependent red shift of SFS maximum. Copyright © 2016 Elsevier B.V. All rights reserved.

Quantitative LC-MS of polymers: determining accurate molecular weight distributions by combined size exclusion chromatography and electrospray mass spectrometry with maximum entropy data processing.

PubMed

Gruendling, Till; Guilhaus, Michael; Barner-Kowollik, Christopher

2008-09-15

We report on the successful application of size exclusion chromatography (SEC) combined with electrospray ionization mass spectrometry (ESI-MS) and refractive index (RI) detection for the determination of accurate molecular weight distributions of synthetic polymers, corrected for chromatographic band broadening. The presented method makes use of the ability of ESI-MS to accurately depict the peak profiles and retention volumes of individual oligomers eluting from the SEC column, whereas quantitative information on the absolute concentration of oligomers is obtained from the RI-detector only. A sophisticated computational algorithm based on the maximum entropy principle is used to process the data gained by both detectors, yielding an accurate molecular weight distribution, corrected for chromatographic band broadening. Poly(methyl methacrylate) standards with molecular weights up to 10 kDa serve as model compounds. Molecular weight distributions (MWDs) obtained by the maximum entropy procedure are compared to MWDs, which were calculated by a conventional calibration of the SEC-retention time axis with peak retention data obtained from the mass spectrometer. Comparison showed that for the employed chromatographic system, distributions below 7 kDa were only weakly influenced by chromatographic band broadening. However, the maximum entropy algorithm could successfully correct the MWD of a 10 kDa standard for band broadening effects. Molecular weight averages were between 5 and 14% lower than the manufacturer stated data obtained by classical means of calibration. The presented method demonstrates a consistent approach for analyzing data obtained by coupling mass spectrometric detectors and concentration sensitive detectors to polymer liquid chromatography.

Highly sensitive fluorescence quantitative detection of specific DNA sequences with molecular beacons and nucleic acid dye SYBR Green I.

PubMed

Xiang, Dongshan; Zhai, Kun; Xiang, Wenjun; Wang, Lianzhi

2014-11-01

A highly sensitive fluorescence method of quantitative detection for specific DNA sequence is developed based on molecular beacon (MB) and nucleic acid dye SYBR Green I by synchronous fluorescence analysis. It is demonstrated by an oligonucleotide sequence of wild-type HBV (target DNA) as a model system. In this strategy, the fluorophore of MB is designed to be 6-carboxyfluorescein group (FAM), and the maximum excitation wavelength and maximum emission wavelength are both very close to that of SYBR Green I. In the presence of targets DNA, the MBs hybridize with the targets DNA and form double-strand DNA (dsDNA), the fluorophore FAM is separated from the quencher BHQ-1, thus the fluorophore emit fluorescence. At the same time, SYBR Green I binds to dsDNA, the fluorescence intensity of SYBR Green I is significantly enhanced. When targets DNA are detected by synchronous fluorescence analysis, the fluorescence peaks of FAM and SYBR Green I overlap completely, so the fluorescence signal of system will be significantly enhanced. Thus, highly sensitive fluorescence quantitative detection for DNA can be realized. Under the optimum conditions, the total fluorescence intensity of FAM and SYBR Green I exhibits good linear dependence on concentration of targets DNA in the range from 2×10(-11) to 2.5×10(-9)M. The detection limit of target DNA is estimated to be 9×10(-12)M (3σ). Compared with previously reported methods of detection DNA with MB, the proposed method can significantly enhance the detection sensitivity. Copyright © 2014 Elsevier B.V. All rights reserved.

Occurrence and sources of antibiotics and their metabolites in river water, WWTPs, and swine wastewater in Jiulongjiang River basin, south China.

PubMed

Jiang, Hongyou; Zhang, Dandan; Xiao, Shichang; Geng, Chunnv; Zhang, Xian

2013-12-01

In this study, the occurrence and sources of five cataloged antibiotics and metabolites were studied in Jiulongjiang River basin, south China. Nineteen antibiotics and 13 metabolites were detected in water samples from 16 river sampling sites, wastewater from 5 swine-raising facilities, and effluent from 5 wastewater treatment plants (WWTPs). The results showed that 12 antibiotics and 6 metabolites were detected in river water samples. Sulfonamides (SAs) and their metabolites were detected at high concentrations (8.59-158.94 ng/L). Tetracyclines (TCs) and their metabolites were frequently detected in swine wastewater, and the maximum concentration was up to the level in milligram per liter. Macrolides (MLs) and β-lactams (β-Ls) were found in all WWTP effluent samples and some river samples, while they were never found in any of the swine wastewater samples. SAs and quinolones (QNs) were detected in all samples. Hierarchical cluster analysis of 16 surface water samples was applied to achieve the spatial distribution characteristics of antibiotics in the Jiulongjiang River. As a result, two categories were obviously obtained. Principal component analysis and redundancy analysis showed that TCs and SAs as well as their metabolites were the major antibiotics in Jiulongjiang River, and they mainly originated from swine wastewater, while the QNs, MLs, and β-Ls in the Jiulongjiang River came from WWTP effluent.

Occurrence, distribution, loads, and yields of selected pesticides in the Little River basin, Kentucky, 2003-04

USGS Publications Warehouse

Crain, Angela S.

2006-01-01

Water resources in the Little River Basin are potentially vulnerable to applications of pesticides associated with both agricultural and nonagricultural activities, because much of the basin is characterized by karst topography. Concerns about water quality resulting from pesticide use in karst areas and lack of data on concentrations of pesticides in surface water led to further investigation of water quality in the Little River Basin, which includes about 600 square miles in Christian and Trigg Counties and a portion of Caldwell County in western Kentucky. Water samples were collected in streams in the Little River Basin, Kentucky during 2003-04 as part of a study conducted in cooperation with the Kentucky Department of Agriculture. The objectives of the study were to assess the occurrence and distribution of pesticides, to evaluate the spatial and seasonal variability of pesticides, and to evaluate loads and yields of selected pesticides in the basin. A total of 91 water samples was collected at 4 fixed-network sites from March through November 2003 and from February through November 2004. An additional 20 samples were collected at 5 synoptic-network sites within the same period. Twenty-four pesticides were detected of the 127 pesticides analyzed in the stream samples. Of the 24 detected pesticides, 15 were herbicides, 7 were insecticides, and 2 were fungicides. The most commonly detected pesticides-atrazine, simazine, metolachlor, and acetochlor-were those most heavily used on crops during the study. Atrazine and simazine were detected in 100 percent of all surface-water samples, and metolachlor and acetochlor were detected in more than 45 percent. The pesticide degradate, deethylatrazine, was detected in 100 percent of the samples. Only one nonagricultural herbicide, prometon, was detected in more than 50 percent of the samples. Diazinon, the most commonly detected insecticide, was found in 25 percent of all samples and was found at all sites except Casey Creek. Metalaxyl was the most commonly detected fungicide (14 percent); most detections were in samples from the Sinking Fork subbasin. Concentrations of herbicides were highest following application in the spring (March-May). In contrast, insecticides typically were present during the summer (June-August). The most commonly detected pesticides in the Little River Basin were found at low concentrations in streams year-round. Atrazine and simazine (row-crop herbicides) had the highest measured concentrations (22 and 6.1 micrograms per liter (?g/L), respectively) and were the most heavily applied herbicides in the basin. Metolachlor also was heavily applied in the basin, but measured concentrations did not exceed 0.32 ?g/L. The insecticide, Malathion, was only detected in 4 percent of the samples, although it was heavily applied in the basin during 2003-04. Most detections of pesticides were at low concentrations in relation to drinking-water standards and guidelines established for the protection of aquatic life. Only two pesticide compounds--atrazine and simazine--exceeded the U.S. Environmental Protection Agency (USEPA) standards for drinking water. Atrazine exceeded the USEPA's maximum contaminant level (MCL) 19 times in 111 detections; simazine exceeded the established MCL 2 times in 111 detections. These exceedences occurred in the spring. Concentrations of atrazine also exceeded the established aquatic-life criterion (1.8 ?g/L) in 32 samples collected from all sites. Concentrations of deethylatrazine, an herbicide-transformation compound, tended to follow the same monthly concentration pattern as its parent compound (atrazine), but concentrations of deethylatrazine were lower than those of atrazine. Atrazine may have been present in the soil much longer at these sites, which might have allowed microbial populations to transform atrazine into deethylatrazine. A statistical comparison of concentrations of selected pesticides among four fixed-network sites

Anthropogenic organic compounds in source water of selected community water systems that use groundwater, 2002-05

USGS Publications Warehouse

Hopple, Jessica A.; Delzer, Gregory C.; Kingsbury, James A.

2009-01-01

Source water, defined as groundwater collected from a community water system well prior to water treatment, was sampled from 221 wells during October 2002 to July 2005 and analyzed for 258 anthropogenic organic compounds. Most of these compounds are unregulated in drinking water and include pesticides and pesticide degradates, gasoline hydrocarbons, personal-care and domestic-use products, and solvents. The laboratory analytical methods used in the study have detection levels that commonly are 100 to 1,000 times lower than State and Federal standards and guidelines for protecting water quality. Detections of anthropogenic organic compounds do not necessarily indicate a concern to human health but rather help to identify emerging issues and track changes in occurrence and concentrations over time. Less than one-half (120) of the 258 compounds were detected in at least one source-water sample. Chloroform, in 36 percent of samples, was the most commonly detected of the 12 compounds that were in about 10 percent or more of source-water samples. The herbicides atrazine, metolachlor, prometon, and simazine also were among the commonly detected compounds. The commonly detected degradates of atrazine - deethylatrazine and deisopropylatrazine - as well as degradates of acetochlor and alachlor, generally were detected at concentrations similar to or greater than concentrations of the parent herbicide. The compounds perchloroethene, trichloroethene, 1,1,1-trichloroethane, methyl tert-butyl ether, and cis-1,2-dichloroethene also were detected commonly. The most commonly detected compounds in source-water samples generally were among those detected commonly across the country and reported in previous studies by the U.S. Geological Survey's National Water-Quality Assessment Program. Relatively few compounds were detected at concentrations greater than human-health benchmarks, and 84 percent of the concentrations were two or more orders of magnitude less than benchmarks. Five compounds (perchloroethene, trichloroethene, 1,2-dibromoethane, acrylonitrile, and dieldrin) were detected at concentrations greater than their human-health benchmark. The human-health benchmarks used for comparison were U.S. Environmental Protection Agency Maximum Contaminant Levels (MCLs) for regulated compounds and Health-Based Screening Levels developed by the U.S. Geological Survey in collaboration with the U.S. Environmental Protection Agency and other agencies for unregulated compounds. About one-half of all detected compounds do not have human-health benchmarks or adequate toxicity information to evaluate results in a human-health context. Ninety-four source-water and finished-water (water that has passed through all the treatment processes but prior to distribution) sites were sampled at selected community water systems during June 2004 to September 2005. Most of the samples were analyzed for compounds that were detected commonly or at relatively high concentrations during the initial source-water sampling. The majority of the finished-water samples represented water blended with water from one or more other wells. Thirty-four samples were from water systems that did not blend water from sampled wells with water from other wells prior to distribution. The comparison of source- and finished-water samples represents an initial assessment of whether compounds present in source water also are present in finished water and is not intended as an evaluation of water-treatment efficacy. The treatment used at the majority of the community water systems sampled is disinfection, which, in general, is not designed to remove the compounds monitored in this study. Concentrations of all compounds detected in finished water were less than their human-health benchmarks. Two detections of perchloroethene and one detection of trichloroethene in finished water had concentrations within an order of magnitude of the MCL. Concentrations of disinfection by-products were

Assessing the guidelines for potassium replacement in pediatric oncology patients receiving amphotericin B.

PubMed

Lafreniere, Janet A; Hamilton, Donald P; Carr, Roxane R

2006-10-01

To examine the practice of potassium chloride (KCl) replacement in pediatric oncology patients receiving amphotericin B (amp-B). A retrospective observational chart review was conducted of patients who received amp-B on the oncology unit between August 2000 and May 2001. A survey was distributed to pediatric oncology pharmacists at other pediatric institutions to assess KCl infusion guidelines across North America. Twenty hypokalemic episodes were identified within 22 patient admissions. Fifty-five percent used KCl replacement (by all combined routes) at rates exceeding the institution's guidelines. Other pediatric institutions varied with respect to the maximum rates and concentration of KCl permitted on non-intensive care units. Based on the data from this review, the KCl administration guidelines for our hospital were changed. We now allow a maximum peripheral line concentration of 60 mEq/L, a maximum central line concentration of 120 mEq/L and a maximum KCl infusion rate of 0.4 mEq/kg/hr without the requirement of a heart monitor. Parenteral Nutrition is now restricted to maximum potassium concentration of 80 mEq/L and fluid-restricted patients are restricted to a maximum concentration of 150 mEq/L.

Vertical profiles of Fukushima Dai-ichi NPP-derived radiocesium concentrations in the waters of the southwestern Okhotsk Sea (2011-2017).

PubMed

Inoue, Mutsuo; Morokado, Toshiki; Fujimoto, Ken; Miki, Shizuho; Kofuji, Hisaki; Isoda, Yutaka; Nagao, Seiya

2018-04-30

We examined the vertical 134 Cs and 137 Cs concentration profiles in the southwestern Okhotsk Sea in 2011, 2013, and 2017. In June 2011, atmospheric deposition-derived 134 Cs from the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) was detected at depths of 0-200 m (0.06-0.6 mBq/L). In July 2013, 134 Cs detected at depths of 100-200 m (∼0.05 mBq/L) was ascribed to the transport of low-level 134 Cs-contaminated water and/or the convection of radioactive depositions (<0.03 mBq/L at depths of 0-50 m). In July 2017, 134 Cs was detected in water samples at depths above 300 m (0.03-0.05 mBq/L), and the inventory, decay-corrected to the FDNPP accident date, exhibited its maximum value (85 Bq/m 2 ) during this period. Combining temperature-salinity data with the concentrations of global fallout-derived 137 Cs led to a plausible explanation for this observation, which is a consequence of re-entry of FDNPP-derived radiocesium through the Kuril Strait from the northwestern North Pacific Ocean to the Okhotsk Sea and subsequent mixing with the south Okhotsk subsurface layer until 2017. Copyright © 2018 Elsevier Ltd. All rights reserved.

The status of pesticide pollution in surface waters (rivers and lakes) of Greece. Part I. Review on occurrence and levels.

PubMed

Konstantinou, Ioannis K; Hela, Dimitra G; Albanis, Triantafyllos A

2006-06-01

This review evaluates and summarizes the results of long-term research projects, monitoring programs and published papers concerning the pollution of surface waters (rivers and lakes) of Greece by pesticides. Pesticide classes mostly detected involve herbicides used extensively in corn, cotton and rice production, organophosphorus insecticides as well as the banned organochlorines insecticides due to their persistence in the aquatic environment. The compounds most frequently detected were atrazine, simazine, alachlor, metolachlor and trifluralin of the herbicides, diazinon, parathion methyl of the insecticides and lindane, endosulfan and aldrin of the organochlorine pesticides. Rivers were found to be more polluted than lakes. The detected concentrations of most pesticides follow a seasonal variation, with maximum values occurring during the late spring and summer period followed by a decrease during winter. Nationwide, in many cases the reported concentrations ranged in low ppb levels. However, elevated concentrations were recorded in areas of high pesticide use and intense agricultural practices. Generally, similar trends and levels of pesticides were found in Greek rivers compared to pesticide contamination in other European rivers. Monitoring of the Greek water resources for pesticide residues must continue, especially in agricultural regions, because the nationwide patterns of pesticide use are constantly changing. Moreover, emphasis should be placed on degradation products not sufficiently studied so far.

Guidelines for developing spacecraft maximum allowable concentrations for Space Station contaminants

NASA Technical Reports Server (NTRS)

1992-01-01

The National Aeronautics and Space Administration (NASA) is preparing to launch a manned space station by the year 1996. Because of concerns about the health, safety, and functioning abilities of the crews, NASA has requested that the National Research Council (NRC) through the Board on Environmental Studies and Toxicology (BEST) provide advice on toxicological matters for the space-station program. The Subcommittee on Guidelines for Developing Spacecraft Maximum Allowable Concentrations for Space Station Contaminants was established by the Committee on Toxicology (COT) to address NASA's concerns. Spacecraft maximum allowable concentrations (SMAC's) are defined as the maximum concentrations of airborne substances (such as gas, vapor, or aerosol) that will not cause adverse health effects, significant discomfort, or degradation in crew performance.

Water quality, pesticide occurrence, and effects of irrigation with reclaimed water at golf courses in Florida

USGS Publications Warehouse

Swancar, Amy

1996-01-01

Reuse of treated wastewater for golf course irrigation is an increasingly popular water management option in Florida, where growth has put stress on potable water supplies. Surface water, ground water, and irrigation water were sampled at three pairs of golf courses quarterly for one year to determine if pesticides were present, and the effect of irrigation with treated effluent on ground-water quality, with an emphasis on interactions of effluent with pesticides. In addition to the six paired golf courses, which were in central Florida, ground water was sampled for pesticides and other constituents at three more golf courses in other parts of the State. This study was the first to analyze water samples from Florida golf courses for a broad range of pesticides. Statistical methods based on the percentage of data above detection limits were used to determine the effects of irrigation with reclaimed water on ground-water quality. Shallow ground water at golf courses irrigated with treated effluent has higher concentrations of chloride, lower concentrations of bicarbonate, and lower pH than ground water at golf courses irrigated with water from carbonate aquifers. There were no statistically significant differences in nutrient concentrations in ground water between paired golf courses grouped by irrigation water type at a 95 percent confidence level. The number of wells where pesticides occurred was significantly higher at the paired golf courses using ground water for irrigation than at ones using reclaimed water. However, the limited occurrences of individual pesticides in ground water make it difficult to correlate differences in irrigation- water quality with pesticide migration to the water table. At some of the golf courses, increased pesticide occurrences may be associated with higher irrigation rates, the presence of well-drained soils, and shallow depths to the surficial aquifer. Pesticides used by golf courses for turf grass maintenance were detected in ground water on seven of nine golf courses studied and in 52 percent of ground-water samples. Concentrations of pesticides in ground water at golf courses were generally low relative to gegulatory guidelines, with 45 percent of all occurrences at trace levels and 92 percent under the maximum contaminant level or guidance concentration. Two of the nine golf courses had not pesticides detectedc in ground water, and a third had only two occurrences, which were at trace levels. Theere were six occurrences of concentrations of arsenic, bentazon, or acephate in ground water above the maximum contaminant level or guidance concentration. Additionally, the following pesticides were detected in ground water from at least one site; atrazine, bromacil, diazinon, diuron, fenamiphos, metalaxyl, oxydiazon, and simazine. The fenamiphos metabolites, fenamiphos sulfoxide and fenamiphos sulfone, also were detected in ground water. Samples from wastewater treatment plants contained trace levels of atrazine, bromacil, and gamma-BHC (Lindane). Concentrations of pesticides in golf course ponds were generally low, with 60 percent of all occurrences at trace levels. All but one of the pond samples collected during the study contained at least one pesticide. The most commonly occurring pesticides in golf course ponds were: atrazine, fenamiphos and fenamiphos sulfoxide, and diuron.

A CFD Analysis of Hydrogen Leakage During On-Pad Purge in the ORION/ARES I Shared Volume

NASA Technical Reports Server (NTRS)

Ajmani, Kumud; Edwards, Daryl A.

2011-01-01

A common open volume is created by the stacking of the Orion vehicle onto the Ares I Upper Stage. Called the Shared Volume, both vehicles contribute to its gas, fluid, and thermal environment. One of these environments is related to hazardous hydrogen gas. While both vehicles use inert purge gas to mitigate any hazardous gas buildup, there are concerns that hydrogen gas may still accumulate and that the Ares I Hazardous Gas Detection System will not be sufficient for monitoring the integrated volume. This Computational Fluid Dynamics (CFD) analysis has been performed to examine these topics. Results of the analysis conclude that the Ares I Hazardous Gas Detection System will be able to sample the vent effluent containing the highest hydrogen concentrations. A second conclusion is that hydrogen does not accumulate under the Orion Service Module (SM) avionics ring as diffusion and purge flow mixing sufficiently dilute the hydrogen to safe concentrations. Finally the hydrogen concentrations within the Orion SM engine nozzle may slightly exceed the 1 percent volume fraction when the entire worse case maximum full leak is directed vertically into the engine nozzle.

Nutrients in groundwaters of the conterminous United States, 1992-1995

USGS Publications Warehouse

Nolan, B.T.; Stoner, J.D.

2000-01-01

Results of a national water quality assessment indicate that nitrate is detected in 71% of groundwater samples, more than 13 times as often as ammonia, nitrite, organic nitrogen, and orthophosphate, based on a common detection threshold of 0.2 mg/L. Shallow groundwater (typically 5 m deep or less) beneath agricultural land has the highest median nitrate concentration (3.4 mg/L), followed by shallow groundwater beneath urban land (1.6 mg/L) and deeper groundwater in major aquifers (0.48 mg/L). Nitrate exceeds the maximum contaminant level, 10 mg/L as nitrogen, in more than 15% of groundwater samples from 4 of 33 major aquifers commonly used as a source of drinking water. Nitrate concentration in groundwater is variable and depends on interactions among several factors, including nitrogen loading, soil type, aquifer permeability, recharge rate, and climate. For a given nitrogen loading, factors that generally increase nitrate concentration in groundwater include well-drained soils, fractured bedrock, and irrigation. Factors that mitigate nitrate contamination of groundwater include poorly drained soils, greater depth to groundwater, artificial drainage systems, intervening layers of unfractured bedrock, a low rate of groundwater recharge, and anaerobic conditions in aquifers.

Heavy metals in produce from urban farms in the San Francisco Bay Area.

PubMed

Kohrman, Hannah; Chamberlain, C Page

2014-01-01

Cadmium (Cd) and lead (Pb) concentrations were analysed in 96 samples of produce from seven urban farms, three suburban farms and three grocery stores in the San Francisco Bay Area in 2011-2012. Cd concentrations were highest in urban chard (0.043 mg kg(-1)) and lowest in urban, suburban and grocery squash (0.003 mg kg(-1)). Pb concentrations were highest in urban kale (0.080 mg kg(-1)) and lowest in grocery squash (0.008 mg kg(-1)). The mean heavy metal concentrations for Cd and Pb in all produce types were well below the maximum limits as set by the Food and Agriculture Organization (FAO) and the World Health Organization (WHO). Individual concentrations of Cd and Pb were below the limits of detection in 26 of 192 analyses. Cd and Pb concentrations in produce from urban farms were not significantly different from produce grown in suburban farms or grocery stores. It was concluded that produce from urban community farms in San Francisco, at least for the farms studied, is safe for human consumption.

Reconstructing Historical VOC Concentrations in Drinking Water for Epidemiological Studies at a U.S. Military Base: Summary of Results

PubMed Central

Maslia, Morris L.; Aral, Mustafa M.; Ruckart, Perri Z.; Bove, Frank J.

2017-01-01

A U.S. government health agency conducted epidemiological studies to evaluate whether exposures to drinking water contaminated with volatile organic compounds (VOC) at U.S. Marine Corps Base Camp Lejeune, North Carolina, were associated with increased health risks to children and adults. These health studies required knowledge of contaminant concentrations in drinking water—at monthly intervals—delivered to family housing, barracks, and other facilities within the study area. Because concentration data were limited or unavailable during much of the period of contamination (1950s–1985), the historical reconstruction process was used to quantify estimates of monthly mean contaminant-specific concentrations. This paper integrates many efforts, reports, and papers into a synthesis of the overall approach to, and results from, a drinking-water historical reconstruction study. Results show that at the Tarawa Terrace water treatment plant (WTP) reconstructed (simulated) tetrachloroethylene (PCE) concentrations reached a maximum monthly average value of 183 micrograms per liter (μg/L) compared to a one-time maximum measured value of 215 μg/L and exceeded the U.S. Environmental Protection Agency’s current maximum contaminant level (MCL) of 5 μg/L during the period November 1957–February 1987. At the Hadnot Point WTP, reconstructed trichloroethylene (TCE) concentrations reached a maximum monthly average value of 783 μg/L compared to a one-time maximum measured value of 1400 μg/L during the period August 1953–December 1984. The Hadnot Point WTP also provided contaminated drinking water to the Holcomb Boulevard housing area continuously prior to June 1972, when the Holcomb Boulevard WTP came on line (maximum reconstructed TCE concentration of 32 μg/L) and intermittently during the period June 1972–February 1985 (maximum reconstructed TCE concentration of 66 μg/L). Applying the historical reconstruction process to quantify contaminant-specific monthly drinking-water concentrations is advantageous for epidemiological studies when compared to using the classical exposed versus unexposed approach. PMID:28868161

Occurrence and Transport of Agricultural Chemicals in Leary Weber Ditch Basin, Hancock County, Indiana, 2003-04

USGS Publications Warehouse

Baker, Nancy T.; Stone, Wesley W.; Wilson, John T.; Meyer, Michael T.

2006-01-01

Leary Weber Ditch Basin, Hancock County, Indiana, is one of seven first-order basins selected from across the United States as part of the Agricultural Chemicals: Source, Transport, and Fate study conducted by the National Water-Quality Assessment Program of the U.S. Geological Survey. The nationwide study was designed to increase the understanding of the links between the sources of water and agricultural chemicals (nutrients and pesticides) and the transport and fate of these chemicals through the environment. Agricultural chemicals were detected in Leary Weber Ditch and in every associated hydrologic compartment sampled during 2003 and 2004. Pesticides were detected more frequently in samples collected from overland flow and from the ditch itself and less frequently in ground-water samples. The lowest concentrations of pesticides and nutrients were detected in samples of rain, soil water, and ground water. The highest concentrations of pesticides and nutrients were detected in samples of tile-drain water, overland flow, and water from Leary Weber Ditch. Samples collected from the tile drain, overland flow and Leary Weber Ditch soon after chemical applications to the fields and coincident with rainfall and increased streamflow had higher concentrations of pesticides and nutrients than samples collected a longer time after the chemicals were applied. A mass-balance mixing analysis based on potassium concentrations indicated that tile drains are the primary contributor of water to Leary Weber Ditch, but overland flow is also an important contributor during periods of high-intensity rainfall. When maximum rainfall intensity was 0.5 inches per hour or lower, overland flow contributed about 10 percent and tile drains contributed about 90 percent of the flow to Leary Weber Ditch. When maximum rainfall intensity was 0.75 inches per hour or greater, overland flow contributed about 40 percent and tile drains contributed about 60 percent of the flow to the ditch. Ground-water flow to Leary Weber Ditch was negligible. Tile drains are an important agricultural-chemical transport path to Leary Weber Ditch, based on the hydrologic contributions of overland flow and tile drains to the ditch. Overland flow is also an important agricultural-chemical transport pathway during high-intensity rainfall; however, storms with high-intensity rainfall are sporadic throughout the year. Tile drains and the soil water moving to the tile drains are the primary transport pathway for agricultural-chemical transport to Leary Weber Ditch during most storms as well as between storms.

Quantitative SERS detection of low-concentration aromatic polychlorinated biphenyl-77 and 2,4,6-trinitrotoluene.

PubMed

Bao, Zhi Yong; Liu, Xin; Chen, Y; Wu, Yucheng; Chan, Helen L W; Dai, Jiyan; Lei, Dang Yuan

2014-09-15

This paper reports a simple label-free high-sensitive method for detecting low-concentration persistent organic pollutants and explosive materials. The proposed method combines surface-enhanced Raman spectroscopy (SERS) and magnetomotive enrichment of the target molecules on the surface of Ag nanoparticles (NPs). This structure can be achieved through self-assembling integration of Ag NPs with ferromagnetic Fe3O4 microspheres, forming a hybrid SERS nanoprobe with both optical and magnetic properties. Moreover, the magnetic response of ferromagnetic Fe3O4 microspheres can be used to dynamically modulate the optical property of Ag NPs through controlling their geometric arrangement on the substrate by applying an external magnetic field. It is also demonstrated from the full-wave numerical simulation results that the maximum electromagnetic field enhancement can be greatly increased by shortening the distance of neighboring Ag NPs and therefore resulting in an improved SERS detecting limit. More importantly, by using the prepared substrate, the SERS signals from organic pollution substances, i.e. aromatic polychlorinated biphenyl-77 and 2,4,6-trinitrotoluene, were quantitatively analyzed. Copyright © 2014 Elsevier B.V. All rights reserved.

Optimized Lateral Flow Immunoassay Reader for the Detection of Infectious Diseases in Developing Countries.

PubMed

Pilavaki, Evdokia; Demosthenous, Andreas

2017-11-20

Detection and control of infectious diseases is a major problem, especially in developing countries. Lateral flow immunoassays can be used with great success for the detection of infectious diseases. However, for the quantification of their results an electronic reader is required. This paper presents an optimized handheld electronic reader for developing countries. It features a potentially low-cost, low-power, battery-operated device with no added optical accessories. The operation of this proof of concept device is based on measuring the reflected light from the lateral flow immunoassay and translating it into the concentration of the specific analyte of interest. Characterization of the surface of the lateral flow immunoassay has been performed in order to accurately model its response to the incident light. Ray trace simulations have been performed to optimize the system and achieve maximum sensitivity by placing all the components in optimum positions. A microcontroller enables all the signal processing to be performed on the device and a Bluetooth module allows transmission of the results wirelessly to a mobile phone app. Its performance has been validated using lateral flow immunoassays with influenza A nucleoprotein in the concentration range of 0.5 ng/mL to 200 ng/mL.

Highly selective and sensitive nanoprobes for cyanide based on gold nanoclusters with red fluorescence emission

NASA Astrophysics Data System (ADS)

Zhang, Guomei; Qiao, Yunyun; Xu, Ting; Zhang, Caihong; Zhang, Yan; Shi, Lihong; Shuang, Shaomin; Dong, Chuan

2015-07-01

We report a novel and environmentally friendly fluorescent probe for detecting the cyanide ion (CN-) using l-amino acid oxidase (LAAOx)-protected Au nanoclusters (LAAOx@AuNCs) with red emission. The fluorescence-based sensing behaviour of LAAOx@AuNCs towards anions was investigated in buffered aqueous media. Among the anions studied, CN- was found to effectively quench the fluorescence emission of AuNCs based on CN- induced Au core decomposition. Excellent sensitivity and selectivity toward the detection of CN- in aqueous solution were observed. The CN- detection limit was determined to be approximately 180 nM, which is 15 times lower than the maximum level (2700 nM) of CN- in drinking water permitted by the World Health Organization (WHO). A linear relationship between the fluorescence intensity and CN- concentration was observed in two ranges of CN- concentration, including 3.2 × 10-6 to 3.4 × 10-5 mol L-1 and 3.81 × 10-5 to 1.04 × 10-4 mol L-1. The high sensitivity and selectivity to CN- among the 17 types of anions make the AuNCs good candidates for use in fluorescent nanoprobes of CN-.

Copper detection in the Asiatic clam Corbicula fluminea: optimum valve closure response.

PubMed

Tran, Damien; Fournier, Elodie; Durrieu, Gilles; Massabuau, Jean-Charles

2004-02-25

When exposed to a contaminant, bivalves close their shell as a protective strategy. The aim of the present study was to estimate the maximum expected dissolved copper sensitivity in the freshwater bivalve Corbicula fluminea using a new approach to determine their potential and limit to detect contaminants. To take into account the rate of spontaneous closures, we integrated stress problems associated with fixation by a valve in usual valvometers and the spontaneous rhythm associated with nycthemeral activity, to optimize the response in conditions where the probability of spontaneous closing was lowest. Moreover, we used an original system with impedance valvometry, using lightweight impedance electrodes, to study free-ranging animals in low stress conditions combined with an analytical approach describing dose-response curves by logistic regression, with valve closure reaction as a function of response time and concentration of contaminant. In C. fluminea, we estimated that copper concentrations > 4 microg/l (95% confidence interval (CI95%), 2.3-8.8 microg/l) must be detected within 5 h after Cu addition. Lower values could not be distinguished from background noise. The threshold values were 2.5 times lower than the values reported in the literature.

Copper detection in the Asiatic clam Corbicula fluminea: optimum valve closure response.

PubMed

Tran, Damien; Fournier, Elodie; Durrieu, Gilles; Massabuau, Jean Charles

2003-11-19

When exposed to a contaminant, bivalves close their shell as a protective strategy. The aim of the present study was to estimate the maximum expected dissolved copper sensitivity in the freshwater bivalve Corbicula fluminea using a new approach to determine their potential and limit to detect contaminants. To take into account the rate of spontaneous closures, we integrated stress problems associated with fixation by a valve in usual valvometers and the spontaneous rhythm associated with nycthemeral activity, to optimize the response in conditions where the probability of spontaneous closing was lowest. Moreover, we used an original system with impedance valvometry, using lightweight impedance electrodes, to study free-ranging animals in low stress conditions combined with an analytical approach describing dose-response curves by logistic regression, with valve closure reaction as a function of response time and concentration of contaminant. In C. fluminea, we estimated that copper concentrations >4 microg/l (95% confidence interval (CI(95%)), 2.3-8.8 microg/l) must be detected within 5 h after Cu addition. Lower values could not be distinguished from background noise. The threshold values were 2.5 times higher than the values reported in the literature.

Stable lead isotopes reveal a natural source of high lead concentrations to gasoline-contaminated groundwater

USGS Publications Warehouse

Landmeyer, J.E.; Bradley, P.M.; Bullen, T.D.

2003-01-01

Concentrations of total lead as high as 1,600 ??g/L were detected in gasoline-contaminated and uncontaminated groundwater at three gasoline-release sites in South Carolina. Total lead concentrations were highest in turbid groundwater samples from gasoline-contaminated and uncontaminated wells, whereas lower turbidity groundwater samples (collected using low-flow methods) had lower total lead concentrations. Dissolved lead concentrations in all wells sampled, however, were less than 15 ??g total lead/L, the current United States Environmental Protection Agency (US EPA) maximum contaminant level (MCL). Because many total lead concentrations exceeded the MCL, the source of lead to the groundwater system at two of the three sites was investigated using a stable lead isotope ratio approach. Plots of the stable isotope ratios of lead (Pb) in groundwater as 207Pb/206Pb versus 208Pb/206Pb, and 208Pb/204Pb versus 206Pb/204Pb were similar to ratios characteristic of lead-based minerals in local rocks of the southeastern US, and were not similar to the stable lead isotopes ratios characteristic of distant lead ore deposits such as Broken Hill, Australia, used to produce tetraethyl lead in gasoline products prior to its phase-out and ban in the United States. Moreover, the isotopic composition of dissolved lead was equivalent to the isotopic composition of total lead in turbid samples collected from the same well, suggesting that the majority of the lead detected in the groundwater samples was associated with sediment particulates of indigenous aquifer material, rather than lead associated with spilled leaded gasoline. The results of this investigation indicate that (1) lead detected at some gasoline-release sites may be derived from the local aquifer material, rather than the gasoline release, and consequently may affect site-specific remediation goals; (2) non-low flow groundwater sampling methods, such as a disposable bailer, may result in turbid groundwater samples and high total lead concentrations, and; (3) stable lead isotopes can be used to clarify the source of lead detected above permissible levels in gasoline-contaminated groundwater systems.

Historical trends in occurrence and atmospheric inputs of halogenated volatile organic compounds in untreated ground water used as a source of drinking water

USGS Publications Warehouse

Shapiro, S.D.; Busenberg, E.; Focazio, M.J.; Plummer, Niel

2004-01-01

Analyses of samples of untreated ground water from 413 community-, non-community- (such as restaurants), and domestic-supply wells throughout the US were used to determine the frequency of detection of halogenated volatile organic compounds (VOCs) in drinking-water sources. The VOC data were compiled from archived chromatograms of samples analyzed originally for chlorofluorocarbons (CFCs) by purge-and-trap gas chromatography with an electron-capture detector (GC-ECD). Concentrations of the VOCs could not be ascertained because standards were not routinely analyzed for VOCs other than trichloromonofluoromethane (CFC-11), dichlorodifluoromethane (CFC-12) and 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113). Nevertheless, the peak areas associated with the elution times of other VOCs on the chromatograms can be classified qualitatively to assess concentrations at a detection limit on the order of parts per quadrillion. Three or more VOCs were detected in 100% (percent) of the chromatograms, and 77.2% of the samples contained 10 or more VOCs. The maximum number of VOCs detected in any sample was 24. Modeled ground-water residence times, determined from concentrations of CFC-12, were used to assess historical trends in the cumulative occurrence of all VOCs detected in this analysis, as well as the occurrence of individual VOCs, such as CFC-11, carbon tetrachloride (CCl4), chloroform and tetrachloroethene (PCE). The detection frequency for all of the VOCs detected has remained relatively constant from approximately 1940 to 2000; however, the magnitude of the peak areas on the chromatograms for the VOCs in the water samples has increased from 1940 to 2000. For CFC-11, CCl4, chloroform and PCE, small peaks decrease from 1940 to 2000, and large peaks increase from 1940 to 2000. The increase in peak areas on the chromatograms from analyses of more recently recharged water is consistent with reported increases in atmospheric concentrations of the VOCs. Approximately 44% and 6.7% of the CCl4 and PCE detections, respectively, in pre-1940 water, and 68% and 62% of the CCl4 and PCE detections, respectively, in water recharged in 2000 exceed solubility equilibrium with average atmospheric concentrations. These exceedences can be attributed to local atmospheric enrichment or direct contaminant input to ground-water flow systems. The detection of VOCs at concentrations indicative of atmospheric sources in 100% of the samples indicates that untreated drinking water from ground-water sources in the US recharged within the past 60 years has been affected by anthropogenic activity. Additional inputs from a variety of sources such as spills, underground injections and leaking landfills or storage tanks increasingly are providing additional sources of contamination to ground water used as drinking-water sources. ?? 2003 Elsevier B.V. All rights reserved.

Impact of downward-mixing ozone on surface ozone accumulation in southern Taiwan.

PubMed

Lin, Ching-Ho

2008-04-01

The ozone that initially presents in the previous day's afternoon mixing layer can remain in the nighttime atmosphere and then be carried over to the next morning. Finally, this ozone can be brought to the ground by downward mixing as mixing depth increases during the daytime, thereby increasing surface ozone concentrations. Variation of ozone concentration during each of these periods is investigated in this work. First, ozone concentrations existing in the daily early morning atmosphere at the altitude range of the daily maximum mixing depth (residual ozone concentrations) were measured using tethered ozonesondes on 52 experimental days during 2004-2005 in southern Taiwan. Daily downward-mixing ozone concentrations were calculated by a box model coupling the measured daily residual ozone concentrations and daily mixing depth variations. The ozone concentrations upwind in the previous day's afternoon mixing layer were estimated by the combination of back air trajectory analysis and known previous day's surface ozone distributions. Additionally, the relationship between daily downward-mixing ozone concentration and daily photochemically produced ozone concentration was examined. The latter was calculated by removing the former from daily surface maximum ozone concentration. The measured daily residual ozone concentrations distributed at 12-74 parts per billion (ppb) with an average of 42 +/- 17 ppb are well correlated with the previous upwind ozone concentration (R2 = 0.54-0.65). Approximately 60% of the previous upwind ozone was estimated to be carried over to the next morning and became the observed residual ozone. The daily downward-mixing ozone contributes 48 +/- 18% of the daily surface maximum ozone concentration, indicating that the downward-mixing ozone is as important as daily photochemically produced ozone to daily surface maximum ozone accumulation. The daily downward-mixing ozone is poorly correlated with the daily photochemically produced ozone and contributes significantly to the daily variation of surface maximum ozone concentrations (R2 = 0.19). However, the contribution of downward-mixing ozone to daily ozone variation is not included in most existing statistical models developed for predicting daily ozone variation. Finally, daily surface maximum ozone concentration is positively correlated with daily afternoon mixing depth, attributable to the downward-mixing ozone.

Fine particle number and mass concentration measurements in urban Indian households.

PubMed

Mönkkönen, P; Pai, P; Maynard, A; Lehtinen, K E J; Hämeri, K; Rechkemmer, P; Ramachandran, G; Prasad, B; Kulmala, M

2005-07-15

Fine particle number concentration (D(p)>10 nm, cm(-3)), mass concentrations (approximation of PM(2.5), microg m(-3)) and indoor/outdoor number concentration ratio (I/O) measurements have been conducted for the first time in 11 urban households in India, 2002. The results indicate remarkable high indoor number and mass concentrations and I/O number concentration ratios caused by cooking. Besides cooking stoves that used liquefied petroleum gas (LPG) or kerosene as the main fuel, high indoor concentrations can be explained by poor ventilation systems. Particle number concentrations of more than 300,000 cm(-3) and mass concentrations of more than 1000 microg m(-3) were detected in some cases. When the number and mass concentrations during cooking times were statistically compared, a correlation coefficient r>0.50 was observed in 63% of the households. Some households used other fuels like wood and dung cakes along with the main fuel, but also other living activities influenced the concentrations. In some areas, outdoor combustion processes had a negative impact on indoor air quality. The maximum concentrations observed in most cases were due to indoor combustion sources. Reduction of exposure risk and health effects caused by poor indoor air in urban Indian households is possible by improving indoor ventilation and reducing penetration of outdoor particles.

Predicting subtle behavioral responses of invertebrates to soil contaminants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Donkin, S.G.

1995-12-31

At concentration levels well below those which cause death and injury to soil invertebrates, a toxic chemical plume may yet effectively damage a soil ecosystem by triggering avoidance behavior among sensitive invertebrates as they move along the concentration gradient. The result may be a soil ecosystem lacking the benefits of effective nutrient cycling and mineralization which a thriving invertebrate population provides. While determining actual detection limits of invertebrates for chemical gradients in soils is experimentally difficult, theoretical calculations have suggested that such limits may be extremely low, and hence many organisms may sense and avoid concentrations of chemicals far belowmore » levels commonly considered acceptable. The minimum gradient (G) that can be detected by a receptor depends on the receptor radius (R), the chemical concentration (C), the diffusion constant of the chemical (D), the velocity of the organism (v), and the time over which the receptor integrates the chemical signal (t). In addition, the characteristics of that gradient are determined by interactions between the chemical and the soil particles (sorption/desorption), and advection through the pore spaces. The example of lead (Pb), a neurotoxic metal with demonstrated behavioral effects on the free-living nematode Caenorhabditis elegans, is used to model a chemical migrating through a soil. Based on experimentally determined Pb concentrations which elicited avoidance behavior in nematodes, and sorption characteristics of defined Pb-soil systems, the minimum detectable gradient (G) produced by a solubilized Pb plume in several soils was modeled. The results predict maximum allowable Pb levels in a soil if a healthy invertebrate community is desired, and suggest areas for further research into the subtle behavioral effects of environmental toxicants ore sensitive invertebrates.« less

Occurrence of pharmaceuticals and personal care products in fish: results of a national pilot study in the United States.

PubMed

Ramirez, Alejandro J; Brain, Richard A; Usenko, Sascha; Mottaleb, Mohammad A; O'Donnell, John G; Stahl, Leanne L; Wathen, John B; Snyder, Blaine D; Pitt, Jennifer L; Perez-Hurtado, Pilar; Dobbins, Laura L; Brooks, Bryan W; Chambliss, C Kevin

2009-12-01

Pharmaceuticals and personal care products are being increasingly reported in a variety of biological matrices, including fish tissue; however, screening studies have presently not encompassed broad geographical areas. A national pilot study was initiated in the United States to assess the accumulation of pharmaceuticals and personal care products in fish sampled from five effluent-dominated rivers that receive direct discharge from wastewater treatment facilities in Chicago, Illinois; Dallas, Texas; Orlando, Florida; Phoenix, Arizona; and West Chester, Pennsylvania, USA. Fish were also collected from the Gila River, New Mexico, USA, as a reference condition expected to be minimally impacted by anthropogenic influence. High performance liquid chromatography-tandem mass spectrometry analysis of pharmaceuticals revealed the presence of norfluoxetine, sertraline, diphenhydramine, diltiazem, and carbamazepine at nanogram-per-gram concentrations in fillet composites from effluent-dominated sampling locations; the additional presence of fluoxetine and gemfibrozil was confirmed in liver tissue. Sertraline was detected at concentrations as high as 19 and 545 ng/g in fillet and liver tissue, respectively. Gas chromatography-tandem mass spectrometry analysis of personal care products in fillet composites revealed the presence of galaxolide and tonalide at maximum concentrations of 2,100 and 290 ng/g, respectively, and trace levels of triclosan. In general, more pharmaceuticals were detected at higher concentrations and with greater frequency in liver than in fillet tissues. Higher lipid content in liver tissue could not account for this discrepancy as no significant positive correlations were found between accumulated pharmaceutical concentrations and lipid content for either tissue type from any sampling site. In contrast, accumulation of the personal care products galaxolide and tonalide was significantly related to lipid content. Results suggest that the detection of pharmaceuticals and personal care products was dependent on the degree of wastewater treatment employed.

Water-quality and sediment-chemistry data of drain water and evaporation ponds from Tulare Lake Drainage District, Kings County, California March 1985 to March 1986

USGS Publications Warehouse

Fujii, Roger

1988-01-01

Trace element and major ion concentrations were measured in water samples collected monthly between March 1985 and March 1986 at the MD-1 pumping station at the Tulare Lake Drainage District evaporation ponds, Kings County, California. Samples were analyzed for selected pesticides several times during the year. Salinity, as measured by specific conductance, ranged from 11,500 to 37,600 microsiemens/centimeter; total recoverable boron ranged from 4,000 to 16,000 micrg/L; and total recoverable molybdenum ranged from 630 to 2,600 microg/L. Median concentrations of total arsenic and total selenium were 97 and 2 microg/L. Atrazine, prometone, propazine, and simazine were the only pesticides detected in water samples collected at the MD-1 pumping station. Major ions, trace elements, and selected pesticides also were analyzed in water and bottom-sediment samples from five of the southern evaporation ponds at Tulare Lake Drainage District. Water enters the ponds from the MD-1 pumping station at pond 1 and flows through the system terminating at pond 10. The water samples increased in specific conductance (21,700 to 90,200 microsiemens/centimeter) and concentrations of total arsenic (110 to 420 microg/L), total recoverable boron (12,000 to 80,000 microg/L) and total recoverable molybdenum (1,200 to 5,500 microg/L) going from pond 1 to pond 10, respectively. Pesticides were not detected in water from any of the ponds sampled. Median concentrations of total arsenic and total selenium in the bottom sediments were 4.0 and 0.9 microg/g, respectively. The only pesticides detected in bottom sediment samples from the evaporation ponds were DDD and DDE, with maximum concentration of 0.8 microg/kilogram. (Author 's abstract)

Variation in glyphosate and AMPA concentrations of surface water and groundwater

NASA Astrophysics Data System (ADS)

Caprile, Ana Clara; Aparicio, Virginia; Sasal, Carolina; Andriulo, Enrique

2017-04-01

The presence of pesticides in various environmental matrices indicate that the soil's ability to function as a bio-physical-chemical reactor is declining. As it operates as an interface between air and water, it causes a negative impact on these two vital resources. Currently, the pampa agriculture is simplified with a marked tendency towards spring-summer crops, where the main crops are RR soybean and corn. Herbicides are neither retained nor degraded in the soil, which results in polluted groundwater and surface waters. The objectives of this study were: a) to verify the presence of glyphosate and aminomethylphosphonic acid (AMPA) in Pergamino stream (a typical representative of the most productive agricultural region of Argentina) under different land use and to detect if in the detections there was a space-time pattern, and b) to verify the detection of these molecules in groundwater of the upper same basin under exclusively rural land use. Surface stream was sampling in six sites (five under rural land use and one under urban-industrial land use) at a rate of one sample by spring, summer and winter seasons (2010-2013, 54 total samples). Groundwater glyphosate and AMPA concentrations were determined in 24 piezometers constructed at two positions of the landscape, across the groundwater flow direction, sampled at two sampling dates (2010 and 2012, 45 total samples). In surface water, glyphosate and AMPA were detected in 54 and 69% of the samples analyzed, respectively. The median concentrations were 0.9 and 0.8 µg L-1 for glyphosate and AMPA and maximal concentrations 258 and 5865 µg L-1, respectively. The sampling site under urban-industrial land use had abnormally high concentrations of glyphosate in the spring (attributed to point pollution), a fact that not allowed to see differences in the remaining sampling times under different land uses. AMPA concentrations under urban-industrial land use were high and higher than rural land use in 3 studied seasons. Under rural land use, AMPA differences between seasons were found, being the highest concentration in spring (1.9 µg L-1). In groundwater glyphosate and AMPA concentrations were detected in 32 and 36% of the analyzed samples respectively. Medium and maximum glyphosate and AMPA concentrations were 0.7 and 1.0 µg L-1, and 2.3 and 6.0 µg L-1, respectively. In the first sampling date, glyphosate and AMPA were not detected probably associated with a dilution during a period of high groundwater recharge. On the contrary, in the second date the two molecules were detected in coincidence with a previous period with lowering water table accompanied by the first recharges. The temporal dynamics showed that herbicides are found in higher concentrations in surface water during the spring, and this is possibly associated with overlapping applications with rains that produce runoff. In groundwater, detections were associated with periods where the first small recharges are produced, which are concentrated in solutes. Loss of the environmental services retention and degradation of glyphosate of the agricultural soils was confirmed

Short-Term Effects of Low-Level Heavy Metal Contamination on Soil Health Analyzed by Nematode Community Structure.

PubMed

Park, Byeong-Yong; Lee, Jae-Kook; Ro, Hee-Myong; Kim, Young Ho

2016-08-01

The short-term effects of low-level contamination by heavy metals (As, Cd, Cu, and Pb) on the soil health were examined by analyzing soil nematode community in soils planted with tomatoes. For this, the soils were irrigated with five metal concentrations ([1, 1/4, 1/4(2), 1/4(3), and 0] × maximum concentrations [MC] detected in irrigation waters near abandoned mine sites) for 18 weeks. Heavy metal concentrations were significantly increased in soils irrigated with MC of heavy metals, among which As and Cu exceeded the maximum heavy metal residue contents of soil approved in Korea. In no heavy metal treatment controls, nematode abundances for all trophic groups (except omnivorous-predatory nematodes [OP]) and colonizer-persister (cp) values (except cp-4-5) were significantly increased, and all maturity indices (except maturity index [MI] of plant-parasitic nematodes) and structure index (SI) were significantly decreased, suggesting the soil environments might have been disturbed during 18 weeks of tomato growth. There were no concentration-dependent significant decreases in richness, abundance, or MI for most heavy metals; however, their significant decreases occurred in abundance and richness of OP and cp-4, MI2-5 (excluding cp-1) and SI, indicating disturbed soil ecosystems, at the higher concentrations (MC and MC/4) of Pb that had the most significant negative correlation coefficients for heavy metal concentrations and nematode community among the heavy metals. Therefore, the short-term effects of low-level heavy metal contamination on soil health can be analyzed by nematode community structures before the appearance of plant damages caused by the abiotic agents, heavy metals.

Hydrogeology and quality of ground water on Guemes Island, Skagit County, Washington

USGS Publications Warehouse

Kahle, S.C.; Olsen, T.D.

1995-01-01

Guemes Island, located in Puget Sound of Washington State, is experiencing population growth and seawater intrusion. The island consists of Pleistocene glacial deposits overlying bedrock. Geologic sections and a map of surficial geology were constructed and used to delineate six hydrogeologic units, three of which are aquifers. The most productive aquifer is the Double Bluff aquifer, situated at or below sea level. Water budget estimates indicate that of the 21-29 inches of precipitation received in a typical year, 0-4 inches runs off, 12-22 inches evapotranspires, and 2-10 inches recharges the ground-water system. Of the water recharged, 0.1-0.3 inches is withdrawn by wells; the remainder recharges deeper aquifer(s) or discharges from the ground-water system to drainage ditches or the sea. The median dissolved-solids concentration was 236 mg/L (milligrams per liter). Half of the samples were classified as moderately hard, the remainder as hard or very hard. Although magnesium-calcium/bicarbonate water types dominate, some samples contained large amounts of sodium and chloride. The median concentration of 0.08 mg/L for nitrate indicates that no widespread contamination from septic systems or livestock exists. Small concentrations of arsenic were present in 5 of 24 samples. Trace concentrations of volatile organic compounds were detected in three of five samples. None of the U.S. Environmental Protection Agency's maximum contaminant levels was exceeded. However, secondary maximum contaminant levels were exceeded for dissolved solids, chloride, manganese, and iron. Seasonal variability of chloride concentration was apparent in water from coastal wells that had chloride concentrations greater than 100 mg/L. Higher values occurred from April through September because of increased pumping and lower recharge.

Relationships between free-living protozoa, cultivable Legionella spp., and water quality characteristics in three drinking water supplies in the Caribbean.

PubMed

Valster, Rinske M; Wullings, Bart A; van den Berg, Riemsdijk; van der Kooij, Dick

2011-10-01

The study whose results are presented here aimed at identifying free-living protozoa (FLP) and conditions favoring the growth of these organisms and cultivable Legionella spp. in drinking water supplies in a tropical region. Treated and distributed water (±30°C) of the water supplies of three Caribbean islands were sampled and investigated with molecular techniques, based on the 18S rRNA gene. The protozoan host Hartmannella vermiformis and cultivable Legionella pneumophila were observed in all three supplies. Operational taxonomic units (OTUs) with the highest similarity to the potential or candidate hosts Acanthamoeba spp., Echinamoeba exundans, E. thermarum, and an Neoparamoeba sp. were detected as well. In total, 59 OTUs of FLP were identified. The estimated protozoan richness did not differ significantly between the three supplies. In supply CA-1, the concentration of H. vermiformis correlated with the concentration of Legionella spp. and clones related to Amoebozoa predominated (82%) in the protozoan community. These observations, the low turbidity (<0.2 nephelometric turbidity units [NTU]), and the varying ATP concentrations (1 to 12 ng liter(-1)) suggest that biofilms promoted protozoan growth in this supply. Ciliophora represented 25% of the protozoan OTUs in supply CA-2 with elevated ATP concentrations (maximum, 55 ng liter(-1)) correlating with turbidity (maximum, 62 NTU) caused by corroding iron pipes. Cercozoan types represented 70% of the protozoan clones in supply CA-3 with ATP concentrations of <1 ng liter(-1) and turbidity of <0.5 NTU in most samples of distributed water. The absence of H. vermiformis in most samples from supply CA-3 suggests that growth of this protozoan is limited at ATP concentrations of <1 ng liter(-1).

Relationships between Free-Living Protozoa, Cultivable Legionella spp., and Water Quality Characteristics in Three Drinking Water Supplies in the Caribbean▿†

PubMed Central

Valster, Rinske M.; Wullings, Bart A.; van den Berg, Riemsdijk; van der Kooij, Dick

2011-01-01

The study whose results are presented here aimed at identifying free-living protozoa (FLP) and conditions favoring the growth of these organisms and cultivable Legionella spp. in drinking water supplies in a tropical region. Treated and distributed water (±30°C) of the water supplies of three Caribbean islands were sampled and investigated with molecular techniques, based on the 18S rRNA gene. The protozoan host Hartmannella vermiformis and cultivable Legionella pneumophila were observed in all three supplies. Operational taxonomic units (OTUs) with the highest similarity to the potential or candidate hosts Acanthamoeba spp., Echinamoeba exundans, E. thermarum, and an Neoparamoeba sp. were detected as well. In total, 59 OTUs of FLP were identified. The estimated protozoan richness did not differ significantly between the three supplies. In supply CA-1, the concentration of H. vermiformis correlated with the concentration of Legionella spp. and clones related to Amoebozoa predominated (82%) in the protozoan community. These observations, the low turbidity (<0.2 nephelometric turbidity units [NTU]), and the varying ATP concentrations (1 to 12 ng liter−1) suggest that biofilms promoted protozoan growth in this supply. Ciliophora represented 25% of the protozoan OTUs in supply CA-2 with elevated ATP concentrations (maximum, 55 ng liter−1) correlating with turbidity (maximum, 62 NTU) caused by corroding iron pipes. Cercozoan types represented 70% of the protozoan clones in supply CA-3 with ATP concentrations of <1 ng liter−1 and turbidity of <0.5 NTU in most samples of distributed water. The absence of H. vermiformis in most samples from supply CA-3 suggests that growth of this protozoan is limited at ATP concentrations of <1 ng liter−1. PMID:21873489

Hydrogeology and water quality in the Snake River alluvial aquifer at Jackson Hole Airport, Jackson, Wyoming, water years 2011 and 2012

USGS Publications Warehouse

Wright, Peter R.

2013-01-01

The hydrogeology and water quality of the Snake River alluvial aquifer at the Jackson Hole Airport in northwest Wyoming was studied by the U.S. Geological Survey, in cooperation with the Jackson Hole Airport Board, during water years 2011 and 2012 as part of a followup to a previous baseline study during September 2008 through June 2009. Hydrogeologic conditions were characterized using data collected from 19 Jackson Hole Airport wells. Groundwater levels are summarized in this report and the direction of groundwater flow, hydraulic gradients, and estimated groundwater velocity rates in the Snake River alluvial aquifer underlying the study area are presented. Analytical results of groundwater samples collected from 10 wells during water years 2011 and 2012 are presented and summarized. The water table at Jackson Hole Airport was lowest in early spring and reached its peak in July or August, with an increase of 12.5 to 15.5 feet between April and July 2011. Groundwater flow was predominantly horizontal but generally had the hydraulic potential for downward flow. Groundwater flow within the Snake River alluvial aquifer at the airport was from the northeast to the west-southwest, with horizontal velocities estimated to be about 25 to 68 feet per day. This range of velocities slightly is broader than the range determined in the previous study and likely is due to variability in the local climate. The travel time from the farthest upgradient well to the farthest downgradient well was approximately 52 to 142 days. This estimate only describes the average movement of groundwater, and some solutes may move at a different rate than groundwater through the aquifer. The quality of the water in the alluvial aquifer generally was considered good. Water from the alluvial aquifer was fresh, hard to very hard, and dominated by calcium carbonate. No constituents were detected at concentrations exceeding U.S. Environmental Protection Agency maximum contaminant levels or health advisories; however, reduction and oxidation (redox) measurements indicate oxygen-poor water in many of the wells. Gasoline-range organics, three volatile organic compounds, and triazoles were detected in some groundwater samples. The quality of groundwater in the alluvial aquifer generally was suitable for domestic and other uses; however, dissolved iron and manganese were detected in samples from many of the monitor wells at concentrations exceeding U.S. Environmental Protection Agency secondary maximum contaminant levels. Iron and manganese likely are both natural components of the geologic materials in the area and may have become mobilized in the aquifer because of redox processes. Additionally, measurements of dissolved-oxygen concentrations and analyses of major ions and nutrients indicate reducing conditions exist at 7 of the 10 wells sampled. Measurements of dissolved-oxygen concentrations (less than 0.1 to 9 milligrams per liter) indicated some variability in the oxygen content of the aquifer. Dissolved-oxygen concentrations in samples from 3 of the 10 wells indicated oxic conditions in the aquifer, whereas low dissolved-oxygen concentrations (less than 1 milligram per liter) in samples from 7 wells indicated anoxic conditions. Nutrients were present in low concentrations in all samples collected. Nitrate plus nitrite was detected in samples from 6 of the 10 monitored wells, whereas dissolved ammonia was detected in small concentrations in 8 of the 10 monitored wells. Dissolved organic carbon concentrations generally were low. At least one dissolved organic carbon concentration was quantified by the laboratory in samples from all 10 wells; one of the concentrations was an order of magnitude higher than other detected dissolved organic carbon concentrations, and slightly exceeded the estimated range for natural groundwater. Samples were collected for analyses of dissolved gases, and field analyses of ferrous iron, hydrogen sulfide, and low-level dissolved oxygen were completed to better understand the redox conditions of the alluvial aquifer. Dissolved gas analyses confirmed low concentrations of dissolved oxygen in samples from wells where reducing conditions exist and indicated the presence of methane gas in samples from several wells. Redox processes in the alluvial aquifer were identified using a model designed to use a multiple-lines-of-evidence approach to distinguish reduction processes. Results of redox analyses indicate iron reduction was the dominant redox process; however, the model indicated manganese reduction and methanogenesis also were taking place in the aquifer. Each set of samples collected during this study included analysis of at least two, but often many anthropogenic compounds. During the previous 2008–09 study at Jackson Hole Airport, diesel-range organics were measured in small (estimated) concentrations in several samples. Samples collected from all 10 wells sampled during the 2011–12 study were analyzed for diesel-range organics, and there were no detections; however, several other anthropogenic compounds were detected in groundwater samples during water years 2011—12 that were not detected during the previous 2008–09 study. Gasoline-range organics, benzene, ethylbenzene, and total xylene were each detected (but reported as estimated concentrations) in at least one groundwater sample. These compounds were not detected during the previous study or consistently during this study. Several possible reasons these compounds were not detected consistently include (1) these compounds are present in the aquifer at concentrations near the analytical method detection limit and are difficult to detect, (2) these compounds were not from a persistent source during this study, and (3) these compounds were detected because of contamination introduced during sampling or analysis. During water years 2011–2012, groundwater samples were analyzed for triazoles, specifically benzotriazole, 4-methyl-1H-benzotriazole, and 5-methyl-1H-benzotriazole. Triazoles are anthropogenic compounds often used as an additive in deicing and anti-icing fluids as a corrosion inhibitor, and can be detected at lower laboratory reporting levels than glycols, which previously had not been detected. Two of the three triazoles measured, 4-methyl-1H-benzotriazole and 5-methyl-1H-benzotriazole, were detected at low concentrations in groundwater at 7 of the 10 wells sampled. The detection of triazole compounds in groundwater downgradient from airport operations makes it unlikely there is a natural cause for the high rates of reduction present in many airport monitor wells. It is more likely that aircraft deicers, anti-icers, or pavement deicers have seeped into the groundwater system and caused the reducing conditions.

Groundwater-quality data in the Borrego Valley, Central Desert, and Low-Use Basins of the Mojave and Sonoran Deserts study unit, 2008-2010--Results from the California GAMA Program

USGS Publications Warehouse

Mathany, Timothy M.; Wright, Michael T.; Beuttel, Brandon S.; Belitz, Kenneth

2012-01-01

Groundwater quality in the 12,103-square-mile Borrego Valley, Central Desert, and Low-Use Basins of the Mojave and Sonoran Deserts (CLUB) study unit was investigated by the U.S. Geological Survey (USGS) from December 2008 to March 2010, as part of the California State Water Resources Control Board (SWRCB) Groundwater Ambient Monitoring and Assessment (GAMA) Program's Priority Basin Project (PBP). The GAMA-PBP was developed in response to the California Groundwater Quality Monitoring Act of 2001 and is being conducted in collaboration with the SWRCB and Lawrence Livermore National Laboratory (LLNL). The CLUB study unit was the twenty-eighth study unit to be sampled as part of the GAMA-PBP. The GAMA CLUB study was designed to provide a spatially unbiased assessment of untreated-groundwater quality in the primary aquifer systems, and to facilitate statistically consistent comparisons of untreated-groundwater quality throughout California. The primary aquifer systems (hereinafter referred to as primary aquifers) are defined as parts of aquifers corresponding to the perforation intervals of wells listed in the California Department of Public Health (CDPH) database for the CLUB study unit. The quality of groundwater in shallow or deep water-bearing zones may differ from the quality of groundwater in the primary aquifers; shallow groundwater may be more vulnerable to surficial contamination. In the CLUB study unit, groundwater samples were collected from 52 wells in 3 study areas (Borrego Valley, Central Desert, and Low-Use Basins of the Mojave and Sonoran Deserts) in San Bernardino, Riverside, Kern, San Diego, and Imperial Counties. Forty-nine of the wells were selected by using a spatially distributed, randomized grid-based method to provide statistical representation of the study unit (grid wells), and three wells were selected to aid in evaluation of water-quality issues (understanding wells). The groundwater samples were analyzed for organic constituents (volatile organic compounds [VOCs], pesticides and pesticide degradates, and pharmaceutical compounds), constituents of special interest (perchlorate and N-nitrosodimethylamine [NDMA]), naturally-occurring inorganic constituents (trace elements, nutrients, major and minor ions, silica, total dissolved solids [TDS], alkalinity, and species of inorganic chromium), and radioactive constituents (radon-222, radium isotopes, and gross alpha and gross beta radioactivity). Naturally-occurring isotopes (stable isotopes of hydrogen, oxygen, boron, and strontium in water, stable isotopes of carbon in dissolved inorganic carbon, activities of tritium, and carbon-14 abundance) and dissolved noble gases also were measured to help identify the sources and ages of sampled groundwater. In total, 223 constituents and 12 water-quality indicators were investigated. Three types of quality-control samples (blanks, replicates, and matrix spikes) were collected at up to 10 percent of the wells in the CLUB study unit, and the results for these samples were used to evaluate the quality of the data for the groundwater samples. Field blanks rarely contained detectable concentrations of any constituent, suggesting that contamination from sample collection procedures was not a significant source of bias in the data for the groundwater samples. Replicate samples generally were within the limits of acceptable analytical reproducibility. Median matrix-spike recoveries were within the acceptable range (70 to 130 percent) for approximately 85 percent of the compounds. This study did not attempt to evaluate the quality of water delivered to consumers; after withdrawal from the ground, untreated groundwater typically is treated, disinfected, and (or) blended with other waters to maintain water quality. Regulatory benchmarks apply to water that is delivered to the consumer, not to untreated groundwater. However, to provide some context for the results, concentrations of constituents measured in the untreated groundwater were compared with regulatory and non-regulatory health-based benchmarks established by the U.S. Environmental Protection Agency (USEPA) and CDPH, and to non-regulatory benchmarks established for aesthetic concerns by CDPH. Comparisons between data collected for this study and benchmarks for drinking water are for illustrative purposes only and are not indicative of compliance or non-compliance with those benchmarks. Most inorganic constituents detected in groundwater samples from the 49 grid wells were detected at concentrations less than drinking-water benchmarks. In addition, all detections of organic constituents from the CLUB study-unit grid-well samples were less than health-based benchmarks. In total, VOCs were detected in 17 of the 49 grid wells sampled (approximately 35 percent), pesticides and pesticide degradates were detected in 5 of the 47 grid wells sampled (approximately 11 percent), and perchlorate was detected in 41 of 49 grid wells sampled (approximately 84 percent). Trace elements, major and minor ions, and nutrients were sampled for at 39 grid wells, and radioactive constituents were sampled for at 23 grid wells; most detected concentrations were less than health-based benchmarks. Exceptions in the grid-well samples include seven detections of arsenic greater than the USEPA maximum contaminant level (MCL-US) of 10 micrograms per liter (μg/L); four detections of boron greater than the CDPH notification level (NL-CA) of 1,000 μg/L; six detections of molybdenum greater than the USEPA lifetime health advisory level (HAL-US) of 40 μg/L; two detections of uranium greater than the MCL-US of 30 μg/L; nine detections of fluoride greater than the CDPH maximum contaminant level (MCL-CA) of 2 milligrams per liter (mg/L); one detection of nitrite plus nitrate (NO2-+NO3-), as nitrogen, greater than the MCL-US of 10 mg/L; and four detections of gross alpha radioactivity (72-hour count), and one detection of gross alpha radioactivity (30-day count), greater than the MCL-US of 15 picocuries per liter. Results for constituents with non-regulatory benchmarks set for aesthetic concerns showed that a manganese concentration greater than the CDPH secondary maximum contaminant level (SMCL-CA) of 50 μg/L was detected in one grid well. Chloride concentrations greater than the recommended SMCL-CA benchmark of 250 mg/L were detected in three grid wells, and one of these wells also had a concentration that was greater than the upper SMCL-CA benchmark of 500 mg/L. Sulfate concentrations greater than the recommended SMCL-CA benchmark of 250 mg/L were measured in six grid wells. TDS concentrations greater than the SMCL-CA recommended benchmark of 500 mg/L were measured in 20 grid wells, and concentrations in 2 of these wells also were greater than the SMCL-CA upper benchmark of 1,000 mg/L.

Degradation of metaldehyde in water by nanoparticle catalysts and powdered activated carbon.

PubMed

Li, Zhuojun; Kim, Jong Kyu; Chaudhari, Vrushali; Mayadevi, Suseeladevi; Campos, Luiza C

2017-07-01

Metaldehyde, an organic pesticide widely used in the UK, has been detected in drinking water in the UK with a low concentration (<1 μg L -1 ) which is still above the European and UK standard requirements. This paper investigates the efficiency of four materials: powdered activated carbon (PAC) and carbon-doped titanium dioxide nanocatalyst with different concentrations of carbon (C-1.5, C-40, and C-80) for metaldehyde removal from aqueous solutions by adsorption and oxidation via photocatalysis. PAC was found to be the most effective material which showed almost over 90% removal. Adsorption data were well fitted to the Langmuir isotherm model, giving a q m (maximum/saturation adsorption capacity) value of 32.258 mg g -1 and a K L (Langmuir constant) value of 2.013 L mg -1 . In terms of kinetic study, adsorption of metaldehyde by PAC fitted well with a pseudo-second-order equation, giving the adsorption rate constant k 2 value of 0.023 g mg -1  min -1 , implying rapid adsorption. The nanocatalysts were much less effective in oxidising metaldehyde than PAC with the same metaldehyde concentration and 0.2 g L -1 loading concentration of materials under UV light; the maximum removal achieved by carbon-doped titanium dioxide (C-1.5) nanocatalyst was around 15% for a 7.5 ppm metaldehyde solution. Graphical abstract ᅟ.

Development and validation of a simulation method, PeCHREM, for evaluating spatio-temporal concentration changes of paddy herbicides in rivers.

PubMed

Imaizumi, Yoshitaka; Suzuki, Noriyuki; Shiraishi, Fujio; Nakajima, Daisuke; Serizawa, Shigeko; Sakurai, Takeo; Shiraishi, Hiroaki

2018-01-24

In pesticide risk management in Japan, predicted environmental concentrations are estimated by a tiered approach, and the Ministry of the Environment also performs field surveys to confirm the maximum concentrations of pesticides with risk concerns. To contribute to more efficient and effective field surveys, we developed the Pesticide Chemicals High Resolution Estimation Method (PeCHREM) for estimating spatially and temporally variable emissions of various paddy herbicides from paddy fields to the environment. We used PeCHREM and the G-CIEMS multimedia environmental fate model to predict day-to-day environmental concentration changes of 25 herbicides throughout Japan. To validate the PeCHREM/G-CIEMS model, we also conducted a field survey, in which river waters were sampled at least once every two weeks at seven sites in six prefectures from April to July 2009. In 20 of 139 sampling site-herbicide combinations in which herbicides were detected in at least three samples, all observed concentrations differed from the corresponding prediction by less than one order of magnitude. We also compared peak concentrations and the dates on which the concentrations reached peak values (peak dates) between predictions and observations. The peak concentration differences between predictions and observations were less than one order of magnitude in 66% of the 166 sampling site-herbicide combinations in which herbicide was detected in river water. The observed and predicted peak dates differed by less than two weeks in 79% of these 166 combinations. These results confirm that the PeCHREM/G-CIEMS model can improve the efficiency and effectiveness of surveys by predicting the peak concentrations and peak dates of various herbicides.

Fate of ivermectin residues in ewes' milk and derived products.

PubMed

Cerkvenik, Vesna; Perko, Bogdan; Rogelj, Irena; Doganoc, Darinka Z; Skubic, Valentin; Beek, Wim M J; Keukens, Henk J

2004-02-01

The fate of ivermectin (IVM) residues was studied throughout the processing of daily bulk milk from 30 ewes (taken up to 33 d following subcutaneous administration of 0.2 mg IVM/kg b.w.) in the following milk products: yoghurt made from raw and pasteurized milk; cheese after pressing; 30- and 60-day ripened cheese; and whey, secondary whey and whey proteins obtained after cheese-making (albumin cheese). The concentration of the H2B1a component of IVM was analysed in these dairy products using an HPLC method with fluorescence detection. The mean recovery of the method was, depending on the matrix, between 87 and 100%. Limits of detection in the order of only 0.1 microg H2B1a/kg of product were achieved. Maximum concentrations of IVM were detected mostly at 2 d after drug administration to the ewes. The highest concentration of IVM was found on day 2 in 60-day ripened cheese (96 microg H2B1a/kg cheese). Secondary whey was the matrix with the lowest concentration of IVM (<0.6 microg H2B1a/ kg). Residue levels fell below the limits of detection between day 5 (for secondary whey) and day 25 (for all cheese samples). In the matrices investigated, linear correlations between daily concentrations of IVM, milk fat and solid content were evident. During yoghurt production, fermentation and thermal stability of IVM was observed. During cheese production, approximately 35% of the IVM, present in the raw (bulk) milk samples, was lost. From the results it was concluded that the processing of ewes' milk did not eliminate the drug residues under investigation. The consequences of IVM in the human diet were discussed. Milk from treated animals should be excluded from production of fat products like cheese for longer after treatment with IVM than for lower fat products.

Long-term recovery of PCB-contaminated surface sediments at the Sangamo-westonl Twelvemile Creek/lake Hartwell Superfund Site.

PubMed

Brenner, Richard C; Magar, Victor S; Ickes, Jennifer A; Foote, Eric A; Abbott, James E; Bingler, Linda S; Crecelius, Eric A

2004-04-15

Natural recovery of contaminated sediments relies on burial of contaminated sediments with increasingly clean sediments over time (i.e., natural capping). Natural capping reduces the risk of resuspension of contaminated surface sediments, and it reduces the potential for contaminant transport into the food chain by limiting bioturbation of contaminated surface or near-surface sediments. This study evaluated the natural recovery of surface sediments contaminated with polychlorinated biphenyls (PCBs) at the Sangamo-Weston/Twelvemile Creek/Lake Hartwell Superfund Site (Lake Hartwell), Pickens County, SC. The primary focus was on sediment recovery resulting from natural capping processes. Total PCB (t-PCB), lead-210 (210Pb), and cesium-137 (137Cs) sediment core profiles were used to establish vertical t-PCB concentration profiles, age date sediments, and determine surface sedimentation and surface sediment recovery rates in 18 cores collected along 10 transects. Four upgradient transects in the headwaters of Lake Hartwell were impacted by historical sediment releases from three upgradient sediment impoundments. These transects were characterized by silt/ clay and sand layering. The highest PCB concentrations were associated with silt/clay layers (1.8-3.5% total organic carbon (TOC)), while sand layers (0.05-0.32% TOC) contained much lower PCB concentrations. The historical sediment releases resulted in substantial burial of PCB-contaminated sediment in the vicinity of these four cores; each core contained less than 1 mg/kg t-PCBs in the surface sand layers. Cores collected from six downgradient Lake Hartwell transects consisted primarily of silt and clay (0.91-5.1% TOC) and were less noticeably impacted by the release of sand from the impoundments. Vertical t-PCB concentration profiles in these cores began with relatively low PCB concentrations at the sediment-water interface and increased in concentration with depth until maximum PCB concentrations were measured at approximately 30-60 cm below the sediment-water interface, ca. 1960-1980. Maximum t-PCB concentrations were followed by progressively decreasing concentrations with depth until the t-PCB concentrations approached the detection limit, where sediments were likely deposited before the onset of PCB use at the Sangamo-Weston plant. The sediments containing the maximum PCB concentrations are associated with the period of maximum PCB release into the watershed. Sedimentation rates averaged 2.1 +/- 1.5 g/(cm2 yr) for 12 of 18 cores collected. The 1994 Record of Decision cleanup requirement is 1.0 mg/kg; two more goals (0.4 and 0.05 mg/kg t-PCBs) also were identified. Average surface sedimentation requirements to meet the three goals were 1.4 +/- 3.7, 11 +/- 4.2, and 33 +/- 11 cm, respectively. Using the age dating results, the average recovery dates to meet these goals were 2000.6 +/- 2.7, 2007.4 +/- 3.5, and 2022.7 +/- 11 yr, respectively. (The 95% prediction limits for these values also are provided.) Despite the reduction in surface sediment PCB concentrations, PCB concentrations measured in largemouth bass and hybrid bass filets continue to exceed the 2.0 mg/kg FDA fish tolerance level.

Investigating the environmental control of planktonic proteobacterial groups during the phytoplankton spring bloom in two contrasting South Coast UK estuaries

NASA Astrophysics Data System (ADS)

Alshatti, Amani

2017-04-01

Seasonal changes in bacterioplankton populations in two south coast UK estuaries Southampton Water and Christchurch Harbour have been investigated between March and November 2013. Four different phylogenetic bacterial groups with two alphaproteobacteria clades were quantitatively determined in subsurface water samples by Fluorescence in-situ hybridization (FISH) with oligonucleotide probes during phytoplankton bloom periods. During the spring phytoplankton bloom in Southampton water, extracted chlorophyll-a concentrations of between 6.7 and 7.6 µg L-1 were detected while gammaproteobacteria relative abundances (28.7-32.8%) and alphaproteobacteria (35.0-44.0%) dominated the eubacteria with smaller proportions of betaproteobacteria (6.4-13.0%) under high salinity conditions (27.9-32.7). Gammaproteobacteria abundance was significantly negatively correlated with chlorophyll-a concentration (R =-0.5, p < 0.05). In the Christchurch Harbour estuary, betaproteobacteria (21.2-41.1%) dominated throughout the study period in lower salinity waters (1.3-20.7). A significant relationship with negative trend was detected in both estuaries between salinity and betaproteobacteria (R = - 0.95, p < 0.0001). A higher proportion of gammaproteobacteria (29.7-30.3 %) occurred after the spring bloom chlorophyll-a concentration of 5-44.3 µg L-1 and proportion of alphaproteobacteria was highly variable. Archaea were detected in low percentages throughout the blooming season in both estuaries with maximum detected relative abundances of 10.6% in Southampton water and 8.2% in Christchurch harbour. The variation in salinity range therefore between the two estuaries plus the differences in phytoplankton biomass had a marked influence on the dominance of the different proteobacterial groups detected.

Water quality, sediment, and soil characteristics near Fargo-Moorhead urban areas as affected by major flooding of the Red River of the North.

PubMed

Guy, A C; Desutter, T M; Casey, F X M; Kolka, R; Hakk, H

2012-01-01

Spring flooding of the Red River of the North (RR) is common, but little information exits on how these flood events affect water and overbank sediment quality within an urban area. With the threat of the spring 2009 flood in the RR predicted to be the largest in recorded history and the concerns about the flooding of farmsteads, outbuildings, garages, and basements, the objectives of this study, which focused on Fargo, ND, and Moorhead, MN, were to assess floodwater quality and to determine the quantity and quality of overbank sediment deposited after floodwaters recede and the quality of soil underlying sediment deposits. 17β-Estradiol was detected in 9 of 24 water samples, with an average concentration of 0.61 ng L. Diesel-range organics were detected in 8 of 24 samples, with an average concentration of 80.0 μg L. The deposition of sediment across locations and transects ranged from 2 to 10 kg m, and the greatest mass deposition of chemicals was closest to the river channel. No gasoline-range organics were detected, but diesel-range organics were detected in 26 of the 27 overbank sediment samples (maximum concentration, 49.2 mg kg). All trace elements detected in the overbank sediments were within ranges for noncontaminated sites. Although flooding has economic, social, and environmental impacts, based on the results of this study, it does not appear that flooding in the RR in F-M led to decreased quality of water, sediment, or soil compared with normal river flows or resident soil. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Quantification of susceptibility change at high-concentrated SPIO-labeled target by characteristic phase gradient recognition.

PubMed

Zhu, Haitao; Nie, Binbin; Liu, Hua; Guo, Hua; Demachi, Kazuyuki; Sekino, Masaki; Shan, Baoci

2016-05-01

Phase map cross-correlation detection and quantification may produce highlighted signal at superparamagnetic iron oxide nanoparticles, and distinguish them from other hypointensities. The method may quantify susceptibility change by performing least squares analysis between a theoretically generated magnetic field template and an experimentally scanned phase image. Because characteristic phase recognition requires the removal of phase wrap and phase background, additional steps of phase unwrapping and filtering may increase the chance of computing error and enlarge the inconsistence among algorithms. To solve problem, phase gradient cross-correlation and quantification method is developed by recognizing characteristic phase gradient pattern instead of phase image because phase gradient operation inherently includes unwrapping and filtering functions. However, few studies have mentioned the detectable limit of currently used phase gradient calculation algorithms. The limit may lead to an underestimation of large magnetic susceptibility change caused by high-concentrated iron accumulation. In this study, mathematical derivation points out the value of maximum detectable phase gradient calculated by differential chain algorithm in both spatial and Fourier domain. To break through the limit, a modified quantification method is proposed by using unwrapped forward differentiation for phase gradient generation. The method enlarges the detectable range of phase gradient measurement and avoids the underestimation of magnetic susceptibility. Simulation and phantom experiments were used to quantitatively compare different methods. In vivo application performs MRI scanning on nude mice implanted by iron-labeled human cancer cells. Results validate the limit of detectable phase gradient and the consequent susceptibility underestimation. Results also demonstrate the advantage of unwrapped forward differentiation compared with differential chain algorithms for susceptibility quantification at high-concentrated iron accumulation. Copyright © 2015 Elsevier Inc. All rights reserved.

Observations in eastern England of elevated methyl iodide concentrations in air of atlantic origin

NASA Astrophysics Data System (ADS)

Oram, D. E.; Penkett, S. A.

Atmospheric methyl iodide (CH 3I) has been measured at a ground-based site in eastern England for two consecutive summers. Maximum values of 43.1 pptv and 28.9 pptv were recorded in 1989 and 1990, respectively. CH 3I was not detectable in the autumn and winter months. Episodes of elevated concentration persisted for periods ranging from a few hours to several days. The origin of much of the observed CH 31 would appear to be the Atlantic Ocean, indicating the presence of large source areas, possibly phytoplankton blooms, in ocean waters. If so, this work provides the first evidence of long-range transport of an important iodine-bearing species at concentrations of hemispheric significance. Estimates are made of the dry deposition velocity of CH 3I and the potential impact of elevated tropospheric levels on the human uptake of iodine.

Wild brown trout affected by historical mining in the Cévennes National Park, France.

PubMed

Monna, F; Camizuli, E; Revelli, P; Biville, C; Thomas, C; Losno, R; Scheifler, R; Bruguier, O; Baron, S; Chateau, C; Ploquin, A; Alibert, P

2011-08-15

In the protected area of the Cévennes National Park (Southern France), 114 wild brown trout (Salmo trutta fario) were captured at six locations affected to different extents by historical mining and metallurgy dating from the Iron Age to Modern Times. Cadmium and lead in trout livers and muscles reflect high sediment contamination, although an age-related effect was also detected for hepatic metal concentrations. Lead isotope signatures confirm exposure to drainage from mining and metallurgical waste. Developmental instability, assessed by fluctuating asymmetry, is significantly correlated with cadmium and lead concentrations in trout tissues, suggesting that local contamination may have affected fish development. Nowadays, the area is among the least industrialized in France. However, our results show that 60% of the specimens at one site exceed EU maximum allowed cadmium or lead concentration in foodstuffs. The mining heritage should not be neglected when establishing strategies for long-term environmental management.

Computerized detection of unruptured aneurysms in MRA images: reduction of false positives using anatomical location features

NASA Astrophysics Data System (ADS)

Uchiyama, Yoshikazu; Gao, Xin; Hara, Takeshi; Fujita, Hiroshi; Ando, Hiromichi; Yamakawa, Hiroyasu; Asano, Takahiko; Kato, Hiroki; Iwama, Toru; Kanematsu, Masayuki; Hoshi, Hiroaki

2008-03-01

The detection of unruptured aneurysms is a major subject in magnetic resonance angiography (MRA). However, their accurate detection is often difficult because of the overlapping between the aneurysm and the adjacent vessels on maximum intensity projection images. The purpose of this study is to develop a computerized method for the detection of unruptured aneurysms in order to assist radiologists in image interpretation. The vessel regions were first segmented using gray-level thresholding and a region growing technique. The gradient concentration (GC) filter was then employed for the enhancement of the aneurysms. The initial candidates were identified in the GC image using a gray-level threshold. For the elimination of false positives (FPs), we determined shape features and an anatomical location feature. Finally, rule-based schemes and quadratic discriminant analysis were employed along with these features for distinguishing between the aneurysms and the FPs. The sensitivity for the detection of unruptured aneurysms was 90.0% with 1.52 FPs per patient. Our computerized scheme can be useful in assisting the radiologists in the detection of unruptured aneurysms in MRA images.

Development of a continuous radon concentration monitoring system in underground soil

NASA Astrophysics Data System (ADS)

Yamamoto, S.; Tarutani, K.; Yamasoto, K.; Iskandar, D.; Iida, T.

2001-06-01

A continuous radon (Rn-222) concentration monitoring system for use in underground soil was developed and tested. The system consists of a 19-mm-diameter, 1100-mm-long detector assembly and a microprocessor based data logger. A small volume chamber is installed at the tip of the detector assembly. A thin ZnS(Ag) scintillator film inside the chamber and a photomultiplier tube (PMT) detect alpha particles from radon and its daughters. When the system is in measurement, the detector part is buried into underground soil. An energy resolution of approximately 70% full width half maximum (FWHM) was obtained for 5.5 MeV alpha particles from Am-241. Both the rise time and fall time for the system were measured to be approximately 1-2 h. Temporal variations in underground radon concentration at different depths were investigated simultaneously using four sets of the developed system. The results confirmed that the developed system is useful for continuous measurement of radon concentration in underground soil.

Kinetics and toxic effects of repeated intravenous dosage of formic acid in rabbits.

PubMed Central

Liesivuori, J.; Kosma, V. M.; Naukkarinen, A.; Savolainen, H.

1987-01-01

Adult male rabbits were injected i.v. with 100 mg buffered formic acid per kg body weight daily for 5 days with 24 h between the doses. The fifth dose was labelled with 14C-formic acid. Rabbits were killed 1, 2 and 20 h after the last injection. The highest formic acid concentrations were found one hour after the fifth dose. Total formic acid concentrations were always higher than radiometrically measured. The maximum concentrations of formic acid in brain, heart, kidney and liver were roughly similar to the concentration which inhibits half of the cytochrome oxidase activity in vitro. Histological studies clearly demonstrated the histotoxic changes at cellular level. Calcium deposits were detected in all organs of the injected rabbits. They were absent in control animals. It seems that the formic acid metabolism is slow and that it may cause sufficient hypoxic acidosis to allow the calcium influx and cellular damage. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:3426949

[Semi-analysis algorithm to retrieve pigment concentrations in the red tide area of the East China Sea].

PubMed

Qiu, Zhong-Feng; Xi, Hong-Yan; He, Yi-Jun; Chen, Jay-Chung; Jian, Wei-Jun

2006-08-01

For the purpose of detecting and forecasting research of red tides to reduce the loss, a semi-analytic algorithm to retrieve chlorophyll-a concentrations was established in the area where red tides often brought out, according to the data collected during the red tides cruise in the East China Sea in April 2002. In the algorithm, empirical equations were made based on the coefficients from the in-situ data, including the optical properties of the research area. The in-situ data were used to validate the algorithm. The discrepancy of chlorophyll-a absorption coefficients and concentrations are mainly located in the region of 30%. The root mean deviation of the chlorophyll-a concentrations between the observed and the calculated is 0.24, the maximum relative deviation 40.93%, the mean relative deviation 18.83% and the correlation coefficient 0.83. The results show that the precision of the algorithm is high and the algorithm is fit for the research area.

Highly hydrogen-sensitive thermal desorption spectroscopy system for quantitative analysis of low hydrogen concentration (˜1 × 1016 atoms/cm3) in thin-film samples

NASA Astrophysics Data System (ADS)

Hanna, Taku; Hiramatsu, Hidenori; Sakaguchi, Isao; Hosono, Hideo

2017-05-01

We developed a highly hydrogen-sensitive thermal desorption spectroscopy (HHS-TDS) system to detect and quantitatively analyze low hydrogen concentrations in thin films. The system was connected to an in situ sample-transfer chamber system, manipulators, and an rf magnetron sputtering thin-film deposition chamber under an ultra-high-vacuum (UHV) atmosphere of ˜10-8 Pa. The following key requirements were proposed in developing the HHS-TDS: (i) a low hydrogen residual partial pressure, (ii) a low hydrogen exhaust velocity, and (iii) minimization of hydrogen thermal desorption except from the bulk region of the thin films. To satisfy these requirements, appropriate materials and components were selected, and the system was constructed to extract the maximum performance from each component. Consequently, ˜2000 times higher sensitivity to hydrogen than that of a commercially available UHV-TDS system was achieved using H+-implanted Si samples. Quantitative analysis of an amorphous oxide semiconductor InGaZnO4 thin film (1 cm × 1 cm × 1 μm thickness, hydrogen concentration of 4.5 × 1017 atoms/cm3) was demonstrated using the HHS-TDS system. This concentration level cannot be detected using UHV-TDS or secondary ion mass spectroscopy (SIMS) systems. The hydrogen detection limit of the HHS-TDS system was estimated to be ˜1 × 1016 atoms/cm3, which implies ˜2 orders of magnitude higher sensitivity than that of SIMS and resonance nuclear reaction systems (˜1018 atoms/cm3).

Optimization of K-edge imaging for vulnerable plaques using gold nanoparticles and energy resolved photon counting detectors: a simulation study.

PubMed

Alivov, Yahya; Baturin, Pavlo; Le, Huy Q; Ducote, Justin; Molloi, Sabee

2014-01-06

We investigated the effect of different imaging parameters, such as dose, beam energy, energy resolution and the number of energy bins, on the image quality of K-edge spectral computed tomography (CT) of gold nanoparticles (GNP) accumulated in an atherosclerotic plaque. A maximum likelihood technique was employed to estimate the concentration of GNP, which served as a targeted intravenous contrast material intended to detect the degree of the plaque's inflammation. The simulation studies used a single-slice parallel beam CT geometry with an x-ray beam energy ranging between 50 and 140 kVp. The synthetic phantoms included small (3 cm in diameter) cylinder and chest (33 × 24 cm(2)) phantoms, where both phantoms contained tissue, calcium and gold. In the simulation studies, GNP quantification and background (calcium and tissue) suppression tasks were pursued. The x-ray detection sensor was represented by an energy resolved photon counting detector (e.g., CdZnTe) with adjustable energy bins. Both ideal and more realistic (12% full width at half maximum (FWHM) energy resolution) implementations of the photon counting detector were simulated. The simulations were performed for the CdZnTe detector with a pixel pitch of 0.5-1 mm, which corresponds to a performance without significant charge sharing and cross-talk effects. The Rose model was employed to estimate the minimum detectable concentration of GNPs. A figure of merit (FOM) was used to optimize the x-ray beam energy (kVp) to achieve the highest signal-to-noise ratio with respect to the patient dose. As a result, the successful identification of gold and background suppression was demonstrated. The highest FOM was observed at the 125 kVp x-ray beam energy. The minimum detectable GNP concentration was determined to be approximately 1.06 µmol mL(-1) (0.21 mg mL(-1)) for an ideal detector and about 2.5 µmol mL(-1) (0.49 mg mL(-1)) for a more realistic (12% FWHM) detector. The studies show the optimal imaging parameters at the lowest patient dose using an energy resolved photon counting detector to image GNP in an atherosclerotic plaque.

Sources and distribution of nitrate in ground water at a farmed field irrigated with sewage treatment-plant effluent, Tallahassee, Florida

USGS Publications Warehouse

Berndt, M.P.

1990-01-01

The city of Tallahassee, Florida began applying sewage treatment-plant effluent to a sprayfield southeast of the city in 1980. Fertilizers containing inorganic nitrogen were also applied in conjunction with the operation of a commercial farm at this site. Analysis of groundwater in the surficial aquifer and the Upper Floridan aquifer have indicated that nitrate concentrations in some wells exceed the prescribed drinking water maximum contaminant level of 10 mg/L (nitrate as nitrogen). Nitrate concentrations greater than the maximum contaminant level were not detected in samples from monitoring wells outside the sprayfield boundary. Analyses of water from the unsaturated zone indicated that conversion of organic nitrogen and ammonia to nitrate was complete before the nitrogen- enriched water reached the water table. Groundwater samples from wells in the surficial and Upper Floridan aquifers less than 100 ft deep located inside sprayed areas had mean concentrations of nitrate much higher than samples from similar wells located outside sprayed areas at the southeast sprayfield. These shallow wells inside the sprayed areas were the only wells in which the maximum contaminant level for nitrate was exceeded. Analyses of the nitrogen isotope ratios in groundwater were used to determine whether the major source of nitrogen was treated sewage or fertilizers. The nitrogen isotope ratios in contaminated groundwater at the southeast sprayfield were compared to those at another sprayfield southwest of the city, where treated sewage was the sole source of nitrogen. Statistical analyses indicated a significant difference in the nitrogen isotope ratios at the two sites, indicating that both nitrogen sources are significant at the southeast sprayfield. (USGS)

Mycotoxins in foods in Lower Saxony (Germany): results of official control analyses performed in 2009.

PubMed

Reinhold, Lilli; Reinhardt, Katja

2011-05-01

In this presentation, the mycotoxin levels-as analysed by the analytical centre for mycotoxin surveillance of the state food laboratory (LAVES Braunschweig)-for approximately 500 food samples are reported. The samples were collected in the year 2009 at retail in the German federal state of Lower Saxony. Aflatoxin and ochratoxin A were analysed in dried fruits, spices, cereals and tree nuts. Ochratoxin A was detected in all samples of dried vine fruits, at levels up to 8.1 μg/kg. Aflatoxins and ochratoxin A were also found in nutmeg and curry powder: the maximum regulatory levels for aflatoxins were exceeded in 25% of the nutmeg samples. Nearly all samples of basmati rice contained aflatoxins, although at levels below the maximum regulatory level in all but one sample. Aflatoxins were also detected in about 50% of hazelnut samples, in 20% of the samples the maximum levels was exceeded (maximum 23.2 μg/kg). In contrast, aflatoxin contents in pistachios were surprisingly low. Fusarium toxins were analysed in cereals and cereal products such as flour, bread, and pasta. Deoxynivalenol (DON) was the predominant toxin found in these samples: DON was found in about 40% of the samples, although the maximum levels were not exceeded (max. 418 μg/kg). Fumonisins (FBs) and zearalenone (ZEA) were specifically analysed in maize products (snacks, flour and oil). Most of these samples (80%) were positive, but at levels not exceeding the maximum levels. Maximum levels were 98 μg/kg (ZEA) and 577 μg/kg (sum of FB1 and FB2). Ergot alkaloids (six major alkaloids) were analysed in rye flour, and approximately 50% were positive. The highest concentration of ergot alkaloids was 1,063 μg/kg; the predominant alkaloids were ergotamine and ergocristine. In conclusion, the results indicate that continuous and efficient control measures for mycotoxins in a wide range of critical foods are necessary to ensure compliance with maximum levels. Although the mycotoxin levels in the vast majority of samples were below maximum levels, year-to-year variation and changes in the production of relevant commodities may result in a different picture in the future.

Abscisic Acid Stimulates Elongation of Excised Pea Root Tips

PubMed Central

Gaither, Douglas H.; Lutz, Donald H.; Forrence, Leonard E.

1975-01-01

Excised Pisum sativum L. root tips were incubated in a pH 5.2 sucrose medium containing abscisic acid. Elongation growth was inhibited by 100 μm abscisic acid. However, decreasing the abscisic acid concentration caused stimulation of elongation, the maximum response (25% to 30%) occurring at 1 μm abscisic acid. Prior to two hours, stimulation of elongation by 1 μm abscisic acid was not detectable. Increased elongation did not occur in abscisic acid-treated root tips of Lens culinaris L., Phaseolus vulgaris L., or Zea mays L. PMID:16659198

Long period grating refractive-index sensor: optimal design for single wavelength interrogation.

PubMed

Kapoor, Amita; Sharma, Enakshi K

2009-11-01

We report the design criteria for the use of long period gratings (LPGs) as refractive-index sensors with output power at a single interrogating wavelength as the measurement parameter. The design gives maximum sensitivity in a given refractive-index range when the interrogating wavelength is fixed. Use of the design criteria is illustrated by the design of refractive-index sensors for specific application to refractive-index variation of a sugar solution with a concentration and detection of mole fraction of xylene in heptane (paraffin).

Detection Times of Diazepam, Clonazepam, and Alprazolam in Oral Fluid Collected From Patients Admitted to Detoxification, After High and Repeated Drug Intake.

PubMed

Nordal, Kristin; Øiestad, Elisabeth L; Enger, Asle; Christophersen, Asbjorg S; Vindenes, Vigdis

2015-08-01

Clonazepam, diazepam, and alprazolam are benzodiazepines with sedative, anticonvulsant, and anxiolytic effects, but their prevalence in drug abuse and drug overdoses has long been recognized. When detection times for psychoactive drugs in oral fluid are reported, they are most often based on therapeutic doses administered in clinical studies. Repeated ingestions of high doses, as seen after drug abuse, are however likely to cause positive samples for extended time periods. Findings of drugs of abuse in oral fluid collected from imprisoned persons might lead to negative sanctions, and the knowledge of detection times of these drugs is thus important to ensure correct interpretation. The aim of this study was to investigate the time window of detection for diazepam, clonazepam, and alprazolam in oral fluid from drug addicts admitted to detoxification. Twenty-five patients with a history of heavy drug abuse admitted to a detoxification ward were included. Oral fluid was collected daily in the morning and the evening and urine samples every morning for 10 days, using the Intercept device. Whole blood samples were collected if the patient accepted. The cutoff levels in oral fluid were 1.3 ng/mL for diazepam, N-desmethyldiazepam, and 7-aminoclonazepam and 1 ng/mL for clonazepam and alprazolam. In urine, the cutoff levels for quantifications were 30 ng/mL for alprazolam, alpha-OH-alprazolam, and 7-aminoclonazepam, 135 ng/mL for N-desmethyldizepam, and 150 ng/mL for 3-OH-diazepam and for all the compounds, the cutoff for the screening analyses were 200 ng/mL. The maximum detection times for diazepam and N-desmethyldiazepam in oral fluid were 7 and 9 days, respectively. For clonazepam and 7-aminoclonazepam, the maximum detection times in oral fluid were 5 and 6 days, respectively. The maximum detection time for alprazolam in oral fluid was 2.5 days. New ingestions were not suspected in any of the cases, because the corresponding concentrations in urine were decreasing. Results from blood samples revealed that high doses of benzodiazepines had been ingested before admission, and explains the longer detection times in oral fluids than reported previously after intake of therapeutic doses of these drugs. This study has shown that oral fluid might be a viable alternative medium to urine when the abuse of benzodiazepines is suspected.

Dissolved Phosphorus Pools and Alkaline Phosphatase Activity in the Euphotic Zone of the Western North Pacific Ocean

PubMed Central

Suzumura, Masahiro; Hashihama, Fuminori; Yamada, Namiha; Kinouchi, Shinko

2012-01-01

We measured pools of dissolved phosphorus (P), including dissolved inorganic P (DIP), dissolved organic P (DOP) and alkaline phosphatase (AP)-hydrolyzable labile DOP (L-DOP), and kinetic parameters of AP activity (APA) in the euphotic zone in the western North Pacific Ocean. Samples were collected from one coastal station in Sagami Bay, Japan, and three offshore stations between the North Pacific subtropical gyre (NPSG) and the Kuroshio region. Although DIP concentrations in the euphotic zone at all stations were equally low, around the nominal method detection limit of 20 nmol L-1, chlorophyll a (Chl a) concentrations were one order of magnitude greater at the coastal station. DOP was the dominant P pool, comprising 62–92% of total dissolved P at and above the Chl a maximum layer (CML). L-DOP represented 22–39% of the total DOP at the offshore stations, whereas it accounted for a much higher proportion (about 85%) in the coastal surface layers. Significant correlations between maximum potential AP hydrolysis rates and DIP concentrations or bacterial cell abundance in the offshore euphotic zone suggest that major APA in the oligotrophic surface ocean is from bacterial activity and regulated largely by DIP availability. Although the range of maximum potential APA was comparable among the environmental conditions, the in situ hydrolysis rate of L-DOP in the coastal station was 10 times those in the offshore stations. L-DOP turnover time at the CML ranged from 4.5 days at the coastal station to 84.4 days in the NPSG. The ratio of the APA half-saturation constant to the ambient L-DOP concentration decreased markedly from the NPSG to the coastal station. There were substantial differences in the rate and efficiency of DOP remineralization and its contribution as the potential P source between the low-phosphate/high-biomass coastal ecosystem and the low-phosphate/low biomass oligotrophic ocean. PMID:22457661

Effects on run-off water quantity and quality of urban organic wastes applied in a degraded semi-arid ecosystem.

PubMed

Martínez, F; Casermeiro, M A; Morales, D; Cuevas, G; Walter, Ingrid

2003-04-15

Biosolids and composted municipal solid wastes were surface-applied (0 and 80 Mg ha(-1)) to a degraded soil in a semi-arid environment to determine their effects on the quantity and quality of run-off water. Three and 4 years after application, a simulated rainfall was performed (intensity=942.5 ml min(-1) and kinetic energy=3.92 J m(-2)) on 0.078 m(2) plots using a portable rainfall simulator. The run-off from the different treatment plots was collected and analysed. The type of treatment was highly related to infiltration, run-off and sediment production. The biosolid-treated plots showed the minimum value of total run-off, maximum time to the beginning of run-off and maximum run-off ratio (the relationship between total rainfall and run-off). The MSW-treated plots showed values intermediate between biosolid-treated plots and control plots. Soil losses were also closely related to treatment type. Control plots showed the maximum sediment yield, MSW-treated plots showed intermediate values, and biosolid plots the minimum values for washout. The concentrations of NH(4)-N and PO(4)-P in the run-off water were significantly higher in the treated plots than in control plots. The highest PO(4)-P value, 0.73 mg l(-1), was obtained in the soil treated with biosolids; NO(3)-N concentration also increased significantly with respect to the control and MSW treatments. NH(4)-N concentrations of 15.6 and 15.0 mg l(-1) were recorded in the soils treated with biosolids and MSW, respectively, values approximately five times higher than those obtained in run-off water from untreated soil. However, the concentrations of all these constituents were lower than threshold limits cited in water quality standards for agricultural use. With the exception of Cu, all trace metals analysed in the run-off water were below detection limits.