Analytical instrument with apparatus for sample concentrating

DOEpatents

Zaromb, Solomon

1989-01-01

A system for analysis of trace concentrations of contaminants in air includes a portable liquid chromatograph and a preconcentrator for the contaminants to be analyzed. The preconcentrator includes a sample bag having an inlet valve and an outlet valve for collecting an air sample. When the sample is collected the sample bag is connected in series with a sorbing apparatus in a recirculation loop. The sorbing apparatus has an inner gas-permeable container containing a sorbent material and an outer gas-impermeable container. The sample is circulated through the outer container and around the inner container for trapping and preconcentrating the contaminants in the sorbent material. The sorbent material may be a liquid having the same composition as the mobile phase of the chromatograph for direct injection thereinto. Alternatively, the sorbent material may be a porous, solid body, to which mobile phase liquid is added after preconcentration of the contaminants for dissolving the contaminants, the liquid solution then being withdrawn for injection into the chromatograph.

Evaluation of organic compounds and trace elements in Amazon Creek Basin, Oregon, September 1990

USGS Publications Warehouse

Rinella, F.A.

1993-01-01

Water and bottom sediment were collected from Amazon Creek, Oregon during a summer low-flow condition and analyzed for different classes of organic compounds, including many from the U.S. Environmental Protection Agency's priority pollutant list. Bottom sediment also was analyzed for trace elements typically associated with urban runoff. Trace-element concentrations in the less than 63 micrometer fraction of Amazon Creek bottom-sediment samples were compared with baseline concentrations (expected 95 percent confidence range) for soils from the Western United States and with concen- trations found in bottom sediment from the Willamette River Basin. Total-digestion concentrations of antimony, arsenic, cadmium, chromium, cobalt, copper, lead, manganese, mercury, nickel, silver, titanium, and zinc were enriched at some or all sites sampled. Whole-water samples from some sites contained concentrations of several chlorophenoxy-acid herbicides, the organophosphorus insecticide diazinon, and several semivolatile priority pollutants. Classes of compounds not detected in whole-water samples included carbamate insecticides, triazine and other nitrogen-containing herbicides, and purgeable organic compounds. Bottom-sediment samples contained many organochlorine compounds, including chlordane, DDT plus metabolites, dieldrin, endrin, heptachlor epoxide (a metabolite of heptachlor), and PCBs at some or all sites sampled. Twenty-four of 54 semivolatile compounds were detected in bottom- sediment samples at some or all sites sampled.

Water quality, organic chemistry of sediment, and biological conditions of streams near an abandoned wood-preserving plant site at Jackson, Tennessee

USGS Publications Warehouse

Bradfield, A.D.; Flexner, N.M.; Webster, D.A.

1993-01-01

An investigation of water quality, organic sediment chemistry, and biological conditions of streams near an abandoned wood-preserving plant site at Jackson, Tennessee, was conducted during December 1990. The study was designed to assess the extent of possible contamination of water and biota in the streams from creosote-related discharge originating at this Superfund site. Central Creek, adjacent to the plant, had degraded water quality and biological conditions. Water samples from the most downstream station on Central Creek contained 30 micrograms per liter of pentachlorophenol, which exceeds the State's criterion maximum concentrations of 9 micrograms per liter for fish and aquatic life. Bottom-sediment samples from stations on Central Creek contained concentrations of acenaphthene, napthalene, and phenanthrene ranging from 1,400 to 2,500 micrograms per kilogram. Chronic or acute toxicity resulted during laboratory experiments using test organisms exposed to creosote-related contaminants. Sediment elutriate samples from Central Creek caused slightly to highly toxic effects on Ceriodaphnia dubia. Pimephales promelas, and Photobacterium phosphoreum. Fish-tissue samples from this station contained concentrations of naphthalene. dibenzofuran, fluorene, and phenanthrene ranging from 1.5 to 3.9 micrograms per kilogram Blue-green algae at this station represented about 79 percent of the organisms counted, whereas diatoms accounted for only 11 percent. Benthic invertebrate and fish samples from Central Creek had low diversity and density. Sediment samples from a station on the South Fork Forked Deer River downstream from its confluence with Central Creek contained concentrations of acenaphthene, anthracene, chrysene, fluoranthene, fluorene, pyrere, and phenanthrene ranging from 2,800 to 69,000 micrograms per kilogram. Sediment elutriate samples using water as elutriate from this station contained concentrations of extractable organic compounds ranging from an estimated 43 to 420 micrograms per liter. Sediment elutriate samples were toxic to Ceriodaphnia dubta, Pimephales promelas, Photobacterium phosphoreum, and Salenastrum capricornulum.

Morphology, Spatial Distribution, and Concentration of Flame Retardants in Consumer Products and Environmental Dusts using Scanning Electron Microscopy and Raman Micro-spectroscopy

PubMed Central

WAGNER, JEFF; GHOSAL, SUTAPA; WHITEHEAD, TODD; METAYER, CATHERINE

2013-01-01

We characterized flame retardant (FR) morphologies and spatial distributions in 7 consumer products and 7 environmental dusts to determine their implications for transfer mechanisms, human exposure, and the reproducibility of gas chromatography-mass spectrometry (GC-MS) dust measurements. We characterized individual particles using scanning electron microscopy / energy dispersive x-ray spectroscopy (SEM/EDS) and Raman micro-spectroscopy (RMS). Samples were screened for the presence of 3 FR constituents (bromine, phosphorous, non-salt chlorine) and 2 metal synergists (antimony and bismuth). Subsequent analyses of select samples by RMS enabled molecular identification of the FR compounds and matrix materials. The consumer products and dust samples possessed FR elemental weight percents of up to 36% and 31%, respectively. We identified 24 FR-containing particles in the dust samples and classified them into 9 types based on morphology and composition. We observed a broad range of morphologies for these FR-containing particles, suggesting FR transfer to dust via multiple mechanisms. We developed an equation to describe the heterogeneity of FR-containing particles in environmental dust samples. The number of individual FR-containing particles expected in a 1-mg dust sample with a FR concentration of 100 ppm ranged from <1 to >1000 particles. The presence of rare, high-concentration bromine particles was correlated with decabromodiphenyl ether concentrations obtained via GC-MS. When FRs are distributed heterogeneously in highly concentrated dust particles, human exposure to FRs may be characterized by high transient exposures interspersed by periods of low exposure, and GC-MS FR concentrations may exhibit large variability in replicate subsamples. Current limitations of this SEM/EDS technique include potential false negatives for volatile and chlorinated FRs and greater quantitation uncertainty for brominated FR in aluminum-rich matrices. PMID:23739093

A study of personal and area airborne asbestos concentrations during asbestos abatement: a statistical evaluation of fibre concentration data.

PubMed

Lange, J H; Lange, P R; Reinhard, T K; Thomulka, K W

1996-08-01

Data were collected and analysed on airborne concentrations of asbestos generated by abatement of different asbestos-containing materials using various removal practices. Airborne concentrations of asbestos are dramatically variable among the types of asbestos-containing material being abated. Abatement practices evaluated in this study were removal of boiler/pipe insulation in a crawl space, ceiling tile, transite, floor tile/mastic with traditional methods, and mastic removal with a high-efficiency particulate air filter blast track (shot-blast) machine. In general, abatement of boiler and pipe insulation produces the highest airborne fibre levels, while abatement of floor tile and mastic was observed to be the lowest. A comparison of matched personal and area samples was not significantly different, and exhibited a good correlation using regression analysis. After adjusting data for outliers, personal sample fibre concentrations were greater than area sample fibre concentrations. Statistical analysis and sample distribution of airborne asbestos concentrations appear to be best represented in a logarithmic form. Area sample fibre concentrations were shown in this study to have a larger variability than personal measurements. Evaluation of outliers in fibre concentration data and the ability of these values to skew sample populations is presented. The use of personal and area samples in determining exposure, selecting personal protective equipment and its historical relevance as related to future abatement projects is discussed.

Development of a testing method for asbestos fibers in treated materials of asbestos containing wastes by transmission electron microscopy

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

Yamamoto, Takashi, E-mail: tyama@nies.go.jp; Kida, Akiko; Noma, Yukio

Highlights: • A high sensitive and selective testing method for asbestos in treated materials of asbestos containing wastes was developed. • Asbestos can be determined at a limits are a few million fibers per gram and a few μg g{sup −1}. • High temperature melting treatment samples were determined by this method. Asbestos fiber concentration were below the quantitation limit in all samples, and total fiber concentrations were determined as 47–170 × 10{sup 6} g{sup −1}. - Abstract: Appropriate treatment of asbestos-containing wastes is a significant problem. In Japan, the inertization of asbestos-containing wastes based on new treatment processes approvedmore » by the Minister of the Environment is promoted. A highly sensitive method for testing asbestos fibers in inertized materials is required so that these processes can be approved. We developed a method in which fibers from milled treated materials are extracted in water by shaking, and are counted and identified by transmission electron microscopy. Evaluation of this method by using asbestos standards and simulated slag samples confirmed that the quantitation limits are a few million fibers per gram and a few μg/g in a sample of 50 mg per filter. We used this method to assay asbestos fibers in slag samples produced by high-temperature melting of asbestos-containing wastes. Fiber concentrations were below the quantitation limit in all samples, and total fiber concentrations were determined as 47–170 × 10{sup −6} f/g. Because the evaluation of treated materials by TEM is difficult owing to the limited amount of sample observable, this testing method should be used in conjunction with bulk analytical methods for sure evaluation of treated materials.« less

Uranium hydrogeochemical and stream sediment reconnaissance of the Newcastle NTMS quadrangle, Wyoming, including concentrations of forty-two additional elements

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

Goff, S.J.; Sandoval, W.F.; Gallimore, D.L.

1980-06-01

During the summer and fall of 1977, 533 water and 1226 sediment samples were collected from 1740 locations within the 18,000 km/sup 2/ area of the Newcastle quadrangle, Wyoming. Water samples were collected from wells and springs; sediment samples were collected from stream channels and from springs. Each water sample was analyzed for uranium, and each sediment sample was analyzed for 43 elements, including uranium and thorium. Uranium concentrations in water samples range from below the detection limit of 0.02 ppB to 702.26 ppB and have a median of 1.73 ppB and a mean of 11.76 ppB. Water samples containingmore » high uranium concentrations (>20 ppB) generally are associated with known uranium mining activity or units known to be uranium bearing. About one-third of the water samples containing high uranium concentrations were collected from locations within the Pumpkin Buttes and Turnercrest-Ross Districts. Nearly half of the water samples containing high uranium concentrations were collected from locations just west of the Monument Hill and Highland Flats-Box Creek Districts. Similar anomalous uranium concentrations in this region have been reported updip from Exxon's Highland uranium deposits. High uranium concentrations were also found associated with the Lance Creek-Old Woman Anticline District.« less

The macronutrients in human milk change after storage in various containers.

PubMed

Chang, Yu-Chuan; Chen, Chao-Huei; Lin, Ming-Chih

2012-06-01

The concentrations of macronutrients in human milk can be influenced by various processes, such as storage, freezing, and thawing, that are performed by lactating working mothers and breast milk banks. We evaluated the impact of various containers on the nutrient concentrations in human milk. A total of 42 breast milk samples from 18 healthy lactating mothers were collected. A baseline macronutrient concentration was determined for each sample. Then, the breast milk samples were divided and stored in nine different commercial milk containers. After freezing at -20°C for 2 days, the milk samples were thawed and analyzed again. A midinfrared human milk analyzer (HMA) was used to measure the protein, fat, and carbohydrate contents. There was a significant decrease in the fat content following the storage, freezing, and thawing processes, ranging from 0.27-0.30 g/dL (p=0.02), but no significant decrease in energy content (p=0.069) was noted in the nine different containers. There were statistically significant increases in protein and carbohydrate concentrations in all containers (p=0.021 and 0.001, respectively), however there were no significant differences between the containers in terms of fat, protein, carbohydrate, or energy contents. Human milk, when subjected to storage, freezing, and thawing processes, demonstrated a significant decrease in fat content (up to 9% reduction) in various containers. It is better for infants to receive milk directly from the mother via breastfeeding. More studies are warranted to evaluate the effects of milk storage on infant growth and development. Copyright © 2012. Published by Elsevier B.V.

Method of and apparatus for determining the similarity of a biological analyte from a model constructed from known biological fluids

DOEpatents

Robinson, Mark R.; Ward, Kenneth J.; Eaton, Robert P.; Haaland, David M.

1990-01-01

The characteristics of a biological fluid sample having an analyte are determined from a model constructed from plural known biological fluid samples. The model is a function of the concentration of materials in the known fluid samples as a function of absorption of wideband infrared energy. The wideband infrared energy is coupled to the analyte containing sample so there is differential absorption of the infrared energy as a function of the wavelength of the wideband infrared energy incident on the analyte containing sample. The differential absorption causes intensity variations of the infrared energy incident on the analyte containing sample as a function of sample wavelength of the energy, and concentration of the unknown analyte is determined from the thus-derived intensity variations of the infrared energy as a function of wavelength from the model absorption versus wavelength function.

Stability of levothyroxine injection in glass, polyvinyl chloride, and polyolefin containers.

PubMed

Frenette, Anne Julie; MacLean, Robert D; Williamson, David; Marsolais, Pierre; Donnelly, Ronald F

2011-09-15

The 24-hour stability of a levothyroxine solution admixed and stored in three common infusion containers and infused through polyvinyl chloride (PVC) tubing was evaluated. Levothyroxine sodium 1-μg/mL injection prepared in glass bottles and PVC and polyolefin bags were assayed using high-performance liquid chromatography at 0, 1, 3, 6, 12, and 24 hours; samples drawn directly from the containers, as well as from the distal end of attached PVC tubing, were assayed. The area under the time-versus-concentration curve (AUC) for predicted and delivered doses was calculated; analysis of variance was used for comparison of the percentages of predicted and actual AUC values. The levothyroxine concentration was stable in glass bottles and polyolefin bags through 24 hours (mean ± S.D. percentage of initial concentration remaining, 103.5% ± 2.5% and 100.0% ± 2.9%, respectively). In the PVC infusion bags, the amount of drug decreased to 90% of the initial concentration within 1 hour and then rose and remained within acceptability limits. The levothyroxine concentration of the samples infused through PVC line from glass and polyolefin containers decreased after 1 hour by about 13%; the loss of the drug from the samples infused from PVC bags was higher (18%), presumably due to additive adsorptive effects. In all samples tested, the drug concentration rebounded and remained above 90% to the end of the study. Levothyroxine sodium 1-μg/mL solution was stable for 24 hours in glass bottles and polyolefin bags but when stored in PVC bags, the concentration decreased by 10% after 1 hour.

Seasonal Variability and Effects of Stormflow on Concentrations of Pesticides and their Degradates in Kisco River and Middle Branch Croton River Surface Water, Croton Reservoir System, New York, May 2000-February 2001

USGS Publications Warehouse

Phillips, Patrick J.; Bode, Robert W.

2004-01-01

Seven herbicides (2,4-D, 2,4-D methyl ester, bromacil, dicamba, diuron, imazaquin, and sulfometuron), four insecticides (carbaryl, diazinon, imidacloprid, and malathion), two fungicides (metalaxyl and myclobutanil), and caffeine (an indicator of wastewater) were detected in at least one sample from the Kisco River at concentrations above 0.1 ug/L (micrograms per liter). Four of these compounds - 2,4-D, 2,4-D methyl ester, dicamba, and metalaxyl - were detected in at least one sample from the Kisco River at a concentration above 1 ug/L. Only three herbicides (2,4-D, imazethapyr, and prometon) and caffeine were detected at concentrations above 0.1 ug/L in one or more of the Middle Branch Croton River samples, and no compounds were detected above 0.4 ug/L in Middle Branch Croton River samples. No samples contained concentrations of pesticides that exceeded human health-based water-quality standards. However, samples from the Kisco River contained four insecticides (carbaryl, chlorpyrifos, diazinon, and malathion) and one herbicide (2,4-D) in concentrations that exceeded water-quality criteria for the protection of aquatic life. Aquatic-life protection criteria were generally exceeded only in stormflow samples collected in June, September, and December 2000. No samples from the Middle Branch Croton River contained target compounds that exceeded water-quality criteria for the protection of aquatic life. Pesticide concentrations were generally higher, and the numbers of compounds generally larger in samples from the Kisco River than in samples from the Middle Branch Croton River, probably because the Kisco River watershed has a greater population density and is more extensively developed. The highest concentrations of most compounds in both streams were detected in stormflow samples collected in June, September, and December 2000. This indicates that stormflow sampling is essential in assessments of pesticide occurrence in streams that drain developed lands. The lowest concentrations of most compounds at both sites were detected in baseflow samples collected from October 2000 through February 2001, although the concentrations of several compounds increased substantially during stormflows at the Kisco River site in November and December, 2000.

Oral sampling methods are associated with differences in immune marker concentrations.

PubMed

Fakhry, Carole; Qeadan, Fares; Gilman, Robert H; Yori, Pablo; Kosek, Margaret; Patterson, Nicole; Eisele, David W; Gourin, Christine G; Chitguppi, Chandala; Marks, Morgan; Gravitt, Patti

2018-06-01

To determine whether the concentration and distribution of immune markers in paired oral samples were similar. Clinical research. Cross-sectional study. Paired saliva and oral secretions (OS) samples were collected. The concentration of immune markers was estimated using Luminex multiplex assay (Thermo Fisher Scientific, Waltham, MA). For each sample, the concentration of respective immune markers was normalized to total protein present and log-transformed. Median concentrations of immune markers were compared between both types of samples. Intermarker correlation in each sampling method and across sampling methods was evaluated. There were 90 study participants. Concentrations of immune markers in saliva samples were significantly different from concentrations in OS samples. Oral secretions samples showed higher concentrations of immunoregulatory markers, whereas the saliva samples contained proinflammatory markers in higher concentration. The immune marker profile in saliva samples is distinct from the immune marker profile in paired OS samples. 2b. Laryngoscope, 128:E214-E221, 2018. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

Assessment of airborne asbestos exposure during the servicing and handling of automobile asbestos-containing gaskets.

PubMed

Blake, Charles L; Dotson, G Scott; Harbison, Raymond D

2006-07-01

Five test sessions were conducted to assess asbestos exposure during the removal or installation of asbestos-containing gaskets on vehicles. All testing took place within an operative automotive repair facility involving passenger cars and a pickup truck ranging in vintage from late 1960s through 1970s. A professional mechanic performed all shop work including engine disassembly and reassembly, gasket manipulation and parts cleaning. Bulk sample analysis of removed gaskets through polarized light microscopy (PLM) revealed asbestos fiber concentrations ranging between 0 and 75%. Personal and area air samples were collected and analyzed using National Institute of Occupational Safety Health (NIOSH) methods 7400 [phase contrast microscopy (PCM)] and 7402 [transmission electron microscopy (TEM)]. Among all air samples collected, approximately 21% (n = 11) contained chrysotile fibers. The mean PCM and phase contrast microscopy equivalent (PCME) 8-h time weighted average (TWA) concentrations for these samples were 0.0031 fibers/cubic centimeters (f/cc) and 0.0017 f/cc, respectively. Based on these findings, automobile mechanics who worked with asbestos-containing gaskets may have been exposed to concentrations of airborne asbestos concentrations approximately 100 times lower than the current Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (PEL) of 0.1 f/cc.

Results of a Study Investigating the Plant Uptake of Explosive Residues From Compost of Explosives-Contaminated Soil Obtained from the Umatilla Army Depot Activity

DTIC Science & Technology

1998-11-01

Avoid contact with samples. Be aware of broken containers, corrosives, irritants, biohazards, flammability, pyrophoricity , reactivity, radioactivity...Revision RO 9/23/97 Page 3 NOj-N by Flow Injection Analysis 6.2.2.2 Low results may be obtained for samples that contain high concentrations of iron ...however, for analytes such as iron that may be found at high concentration, a more appropriate test would be to use a concentration near the upper

Spatial Distribution of Elemental Concentrations in Street Dust of Hanoi, Vietnam.

PubMed

Phi, Thai Ha; Chinh, Pham Minh; Hung, Nguyen The; Ly, Luong Thi Mai; Thai, Phong K

2017-02-01

Street dust samples were collected at 163 locations across four different zones of Hanoi, Vietnam, covering different traffic and population densities. Samples were sieved into three fractions of different particle sizes and analyzed for elemental concentrations (K, Ca, Mn, Fe, Zn, Pb) using an X-ray fluorescence (XRF) instrument. The metal concentrations in street dust were compared among different sampling zones and with samples from background to evaluate the degree of pollution. The smallest size particle fraction (diameter <75 μm) contained higher concentrations of metals than the coarser ones (diameters = 75-180 and >180 μm). While concentrations of metals like Ca and Fe are spatially similar, concentrations of Pb and Zn in street dust varied between different zones, with the highest concentrations observed in dust from the downtown area, and lowest levels in the new suburb areas. Overall, compared to studies from cities in other countries, the mean concentration of Pb in street dust in Hanoi was relatively low, suggesting a lower risk to human health due to inhalation or ingestion of Pb-containing dust particles than in cities where Pb concentrations were several times higher.

Summary geochemical maps for samples of rock, stream sediment, and nonmagnetic heavy-mineral concentrate, Sweetwater Roadless Area, Mono County, California and Lyon and Douglas Counties, Nevada

USGS Publications Warehouse

Chaffee, Maurice A.

1986-01-01

Map A shows the locations of all sites where rock samples were collected for this report and the distributions of anomalous concentrations for 12 elements in the 127 rock samples collected. In a similar manner, map B shows the collection sites for 59 samples of minus-60-mesh stream sediment, and 59 samples of nonmagnetic heavy-mineral concentrate derived from stream sediment and also shows the distributions of anomalous concentrations for 13 elements in the stream-sediment samples and 17 elements in the concentrate samples. Map C shows outlines of those drainage basins containing samples of stream sediment and concentrate with anomalous element concentrations and also shows weighted values for each outlined basin based on the number of elements with anomalous concentrations in each stream-sediment and concentrate sample and on the degree to which these concentrations are anomalous in each sample.

The use of fluoride as a natural tracer in water and the relationship to geological features: Examples from the Animas River Watershed, San Juan Mountains, Silverton, Colorado

USGS Publications Warehouse

Bove, D.J.; Walton-Day, K.; Kimball, B.A.

2009-01-01

Investigations within the Silverton caldera, in southwestern Colorado, used a combination of traditional geological mapping, alteration-assemblage mapping, and aqueous geochemical sampling that showed a relationship between geological and hydrologic features that may be used to better understand the provenance and evolution of the water. Veins containing fluorite, huebnerite, and elevated molybdenum concentrations are temporally and perhaps genetically associated with the emplacement of high-silica rhyolite intrusions. Both the rhyolites and the fluorite-bearing veins produce waters containing elevated concentrations of F-, K and Be. The identification of water samples with elevated F/Cl molar ratios (> 10) has also aided in the location of water draining F-rich sources, even after these waters have been diluted substantially. These unique aqueous geochemical signatures can be used to relate water chemistry to key geological features and mineralized source areas. Two examples that illustrate this relationship are: (1) surface-water samples containing elevated F-concentrations (> 1.8 mg/l) that closely bracket the extent of several small high-silica rhyolite intrusions; and (2) water samples containing elevated concentrations of F-(> 1.8 mg/ l) that spatially relate to mines or areas that contain late-stage fluorite/huebnerite veins. In two additional cases, the existence of high F-concentrations in water can be used to: (1) infer interaction of the water with mine waste derived from systems known to contain the fluorite/huebnerite association; and (2) relate changes in water quality over time at a high elevation mine tunnel to plugging of a lower elevation mine tunnel and the subsequent rise of the water table into mineralized areas containing fluorite/huebnerite veining. Thus, the unique geochemical signature of the water produced from fluorite veins indicates the location of high-silica rhyolites, mines, and mine waste containing the veins. Existence of high F-concentrations along with K and Be in water in combination with other geological evidence may be used to better understand the provenance of the water. ?? 2009 AAG/Geological Society of London.

Fecal-indicator bacteria and Escherichia coli pathogen data collected near a novel sub-irrigation water-treatment system in Lenawee County, Michigan, June-November 2007

USGS Publications Warehouse

Duris, Joseph W.; Beeler, Stephanie

2008-01-01

The U.S. Geological Survey, in cooperation with the Lenawee County Conservation District in Lenawee County, Mich., conducted a sampling effort over a single growing season (June to November 2007) to evaluate the microbiological water quality around a novel livestock reservoir wetland sub-irrigation system. Samples were collected and analyzed for fecal coliform bacteria, Escherichia coli (E. coli) bacteria, and six genes from pathogenic strains of E. coli.A total of 73 water-quality samples were collected on nine occasions from June to November 2007. These samples were collected within the surface water, shallow ground water, and the manure-treatment system near Bakerlads Farm near Clayton in Lenawee County, Mich. Fecal coliform bacteria concentrations ranged from 10 to 1.26 million colony forming units per 100 milliliters (CFU/100 mL). E. coli bacteria concentrations ranged from 8 to 540,000 CFU/100 mL. Data from the E. coli pathogen analysis showed that 73 percent of samples contained the eaeA gene, 1 percent of samples contained the stx2 gene, 37 percent of samples contained the stx1 gene, 21 percent of samples contained the rfbO157 gene, and 64 percent of samples contained the LTIIa gene.

Hydrogeochemical survey of groundwater for selected areas in the Arabian Shield and in cover rocks, Kingdom of Saudi Arabia

USGS Publications Warehouse

McHugh, John B.; Miller, W. Roger

1989-01-01

In the spring of 1984, a hydrogeochemical survey was conducted in the Kingdom of Saudi Arabia to test ground water as a sampling medium in exploration for mineral deposits. Eighty-one water samples (mostly from wells) were collected. The samples were analysed for the presence and concentration of major cations and anions, as well as a suite of trace elements. Most of the water samples contained high concentrations of dissolved salts. The majority of the samples showed no significant amounts of the trace elements. A few well-water samples contained moderately anomalous concentrations of zinc, molybdenum, and uranium. These anomalies could be due to salinity effects, contamination, or the proximity of mineral sources. This survey has established some baseline water-chemistry data, especially for the trace metals, which to date have not been reported in ground water in the Kingdom of Saudi Arabia.

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.

Assessment of soil and water contaminants from selected locations in and near the Idaho Army National Guard Orchard Training Area, Ada County, Idaho, 2001-2003

USGS Publications Warehouse

Parliman, D.J.

2004-01-01

In 2001, the National Guard Bureau and the U.S. Geological Survey began a project to compile hydrogeologic data and determine presence or absence of soil, surface-water, and ground-water contamination at the Idaho Army National Guard Orchard Training Area in southwestern Idaho. Between June 2002 and April 2003, a total of 114 soil, surface-water, ground-water, precipitation, or dust samples were collected from 68 sample sites (65 different locations) in the Orchard Training Area (OTA) or along the vehicle corridor to the OTA. Soil and water samples were analyzed for concentrations of selected total trace metals, major ions, nutrients, explosive compounds, semivolatile organics, and petroleum hydrocarbons. Water samples also were analyzed for concentrations of selected dissolved trace metals and major ions. Distinguishing naturally occurring large concentrations of trace metals, major ions, and nutrients from contamination related to land and water uses at the OTA was difficult. There were no historical analyses for this area to compare with modern data, and although samples were collected from 65 locations in and near the OTA, sampled areas represented only a small part of the complex OTA land-use areas and soil types. For naturally occurring compounds, several assumptions were made?anomalously large concentrations, when tied to known land uses, may indicate presence of contamination; naturally occurring concentrations cannot be separated from contamination concentrations in mid- and lower ranges of data; and smallest concentrations may represent the lowest naturally occurring range of concentrations and (or) the absence of contaminants related to land and water uses. Presence of explosive, semivolatile organic (SVOC), and petroleum hydrocarbon compounds in samples indicates contamination from land and water uses. In areas along the vehicle corridor and major access roads within the OTA, most trace metal, major ion, and nutrient concentrations in soil samples were not in the upper 10th percentile of data, but concentrations of 25 metals, ions, or nutrients were in the upper 10th percentile in a puddle sample near the heavy equipment maneuvering area, MPRC-H. The largest concentrations of tin, ammonia, and nitrite plus nitrate (as nitrogen) in water from the OTA were detected in a sample from this puddle. Petroleum hydrocarbons were the most common contaminant, detected in all soil and surface-water samples. An SVOC, bis (2-ethylhexyl) phthalate, a plasticizer, was detected at a site along the vehicle corridor. In Maneuver Areas within the OTA, many soil samples contained at least one trace metal, major ion, or nutrient in the upper 10th percentile of data, and the largest concentrations of cobalt, iron, mercury, titanium, sodium, ammonia, or total phosphorus were detected in 6 of 13 soil samples outside the Tadpole Lake area. The largest concentrations of aluminum, arsenic, beryllium, nickel, selenium, silver, strontium, thallium, vanadium, chloride, potassium, sulfate, and nitrite plus nitrate were detected in soil samples from the Tadpole Lake area. Water from Tadpole Lake contained the largest total concentrations of 19 trace metals, 4 major ions, and 1 nutrient. Petroleum hydrocarbons were detected in 5 soil samples and water from Tadpole Lake. SVOCs related to combustion of fuel or plasticizers were detected in 1 soil sample. Explosive compounds were detected in 1 precipitation sample.In the Impact Area within the OTA, most soil samples contained at least one trace metal, major ion, or nutrient in the upper 10th percentile of data, and the largest concentrations of barium, chromium, copper, manganese, lead, or orthophosphate were detected in 6 of the 18 soil samples. Petroleum hydrocarbons were detected in 4 soil samples, SVOCs in 6 samples, and explosive compounds in 4 samples. In the mobilization and training equipment site (MATES) compound adjacent to the OTA, all soil and water samples contained at lea

Nitrate, arsenic and chloride pollution of drinking water in Northern Greece. Elaboration by applying GIS.

PubMed

Fytianos, Konstantinos; Christophoridis, Christophoros

2004-01-01

The general profile of the pollution of drinking water, originating from groundwater, by nitrates, chloride and arsenic, in the Prefecture of Thessaloniki, was studied in this project. Samples (tap water) were collected from 52 areas-villages of the Prefecture, during a period of 6 months. The analytical results were related to certain points on the map of the area, thus producing coloured representations of the Prefecture, according to the concentration of the corresponding pollutant. The statistical analysis of the data led to some conclusions concerning the causes of pollution and the relation of the concentrations to certain physico-chemical parameters. Nitrate concentration of samples collected from two specific regions were especially high, sometimes above the highest permitted level. A limited number of samples (13.5%) contained arsenic concentrations above the imminent EC drinking water limit (10 ppb). The majority of the tap water samples, collected from areas along the seashore contained increased concentrations of chloride ions, which is a clear indication of seawater intrusion into the related aquifers.

Effect of a polyethylene-lined administration set on the availability of diazepam injection.

PubMed

Hancock, B G; Black, C D

1985-02-01

Delivery of diazepam through a polyethylene-lined i.v. administration set and through a polyvinyl chloride (PVC) set was compared. Diazepam was prepared in concentrations of 50 mg/500 mL and 100 mg/500 mL in 0.9% sodium chloride injection and 5% dextrose injection in glass containers. Diazepam concentrations were measured by high-performance liquid chromatography at 0 through 5 hours in samples collected simultaneously from the glass solution containers and from the distal ends of a PVC administration set and a polyethylene-lined (non-PVC) set. Flow rates of 50 and 100 mL/hr were tested. For the non-PVC sets, diazepam concentration in the infusate was not significantly different from concentration in the glass container at any sampling time. The overall percentage of diazepam recovered was 100.7 +/- 6.8%. For the PVC sets, diazepam concentration in the infusate was less than in the container at all sampling times, and the overall percentage of diazepam recovered was 65.4 +/- 13.3% (significantly different from delivery for the non-PVC sets). Delivery through the non-PVC sets was not affected by flow rate, type of solution, or concentration of diazepam. For infusion periods of up to five hours, delivery of diazepam through polyethylene-lined i.v. administration sets was superior to delivery through polyvinyl chloride sets.

A LC-MS method allowing the analysis of HMX and RDX present at the picogram level in natural aqueous samples without a concentration step.

PubMed

Vigneau, Olivier; Machuron-Mandard, Xavier

2009-03-15

The introduction of chloroform into the nebulising gas of a LC/MS electrospray interface (ESI), in a perfectly controlled way, leads to the formation of intense adducts ([M+Cl](-)) when a mobile phase containing HMX (1,3,5,7-tetranitro-1,3,5,7-tetrazacyclooctane or octogen) and RDX (1,3,5-trintro-1,3,5-triazacyclohexane or hexogen) is eluted. This LC/MS method allows the direct analysis of aqueous samples containing HMX and RDX at the pictogram level without a concentration step. The method is used to determine HMX and RDX concentrations in ground water samples from a military site.

Collection of Pyrethroids in Water and Sediment Matrices: Development and Validation of a Standard Operating Procedure

USGS Publications Warehouse

Hladik, Michelle; Orlando, James L.; Kuivila, Kathryn

2009-01-01

Loss of pyrethroid insecticides onto surfaces during sample collection can confound the interpretation of analytical and toxicity test results. Sample collection devices, container materials, and water matrix composition have a significant influence on the association of pyrethroids to container walls, which can be as high as 50 percent. Any sample collection method involving transfer through multiple containers or pieces of equipment increases the potential for pyrethroid loss. This loose 'surface-association' with container walls can be reversed through agitation. When sampling water matrices with pumps or autosamplers, no pyrethroids were lost as long as the water was moving continuously through the system. When collecting water matrices in containers, the material with the least amount of pyrethroid sorption is as follows: glass less than (<) plastic less than (<) Teflon. Additionally, pyrethroids were easier to re-suspend from the glass container walls. Since the amount of surface-association is proportional to the ratio of volume-to-contact-area of the sample, taking larger-volume field samples (greater than 3 liters) reduced pyrethroid losses to less than 10 percent. The amount of surface-association cannot be predicted easily because of the dependence on water matrix composition; samples with higher dissolved organic carbon or suspended-sediment concentrations were observed to have lower percent loss. Sediment samples were not affected by glass-container sorption (the only containers tested). Standardized sample-collection protocols are critical to yield accurate pyrethroid concentrations for assessment of potential effects, and have been summarized in an accompanying standard operating procedure.

Influence of Temperature on Free Radical Generation in Propolis-Containing Ointments

PubMed Central

Ramos, Pawel; Pilawa, Barbara

2016-01-01

Free radicals thermally generated in the ointments containing propolis were studied by electron paramagnetic resonance (EPR) spectroscopy. The influence of temperature on the free radical concentration in the propolis ointments was examined. Two ointment samples with different contents of propolis (5 and 7%, resp.) heated at temperatures of 30°C, 40°C, 50°C, and 60°C, for 30 min., were tested. Homogeneously broadened EPR lines and fast spin-lattice interactions characterized all the tested samples. Free radicals concentrations in the propolis samples ranged from 1018 to 1020 spin/g and were found to grow in both propolis-containing ointments along with the increasing heating temperature. Free radical concentrations in the ointments containing 5% and 7% of propolis, respectively, heated at temperatures of 30°C, 40°C, and 50°C were only slightly different. Thermal treatment at the temperature of 60°C resulted in a considerably higher free radical formation in the sample containing 7% of propolis when related to the sample with 5% of that compound. The EPR examination indicated that the propolis ointments should not be stored at temperatures of 40°C, 50°C, and 60°C. Low free radical formation at the lowest tested temperatures pointed out that both examined propolis ointments may be safely stored up to the temperature of 30°C. PMID:27563336

Mercury methylation at mercury mines in the Humboldt River Basin, Nevada, USA

USGS Publications Warehouse

Gray, J.E.; Crock, J.G.; Lasorsa, B.K.

2002-01-01

Total Hg and methylmercury concentrations were measured in mine-waste calcines (retorted ore), sediment, and water samples collected in and around abandoned mercury mines in western Nevada to evaluate Hg methylation at the mines and in the Humboldt River Basin. Mine-waste calcines contain total Hg concentrations as high as 14 000 ??g g-1. Stream-sediment samples collected within 1 km of the mercury mines contain total Hg concentrations as high as 170 ??g g-1, whereas stream sediments collected at a distance >5 km from the mines, and those collected from the Humboldt River and regional baseline sites, contain total Hg concentrations 8 km from the nearest mercury mines. Our data indicate little transference of Hg and methylmercury from the sediment to the water column due to the lack of mine runoff in this desert climate.

Ionic relaxation in PEO/PVDF-HFP-LiClO4 blend polymer electrolytes: dependence on salt concentration

NASA Astrophysics Data System (ADS)

Das, S.; Ghosh, A.

2016-06-01

In this paper, we have studied the effect of LiClO4 salt concentration on the ionic conduction and relaxation in poly ethylene oxide (PEO) and poly (vinylidene fluoride hexafluoropropylene) (PVDF-HFP) blend polymer electrolytes, in which the molar ratio of ethylene oxide segments to lithium ions (R  =  EO: Li) has been varied between 3 and 35. We have observed two phases in the samples containing low salt concentrations (R  >  9) and single phase in the samples containing high salt concentrations (R  ⩽  9). The scanning electron microscopic images indicate that there exists no phase separation in the blend polymer electrolytes. The temperature dependence of the ionic conductivity shows two slopes corresponding to high and low temperatures and follows Arrhenius relation for the samples containing low salt concentrations (R  >  9). The conductivity relaxation as well as the structural relaxation has been clearly observed at around 104 Hz and 106 Hz for these concentrations of the blended electrolytes. However, a single conductivity relaxation peak has been observed for the compositions with R  ⩽  9. The scaling of the conductivity spectra shows that the relaxation mechanism is independent of temperature, but depends on salt concentration.

Ochratoxin A Concentrations in a Variety of Grain-Based and Non-Grain-Based Foods on the Canadian Retail Market from 2009 to 2014.

PubMed

Kolakowski, Beata; O'Rourke, Sarah M; Bietlot, Henri P; Kurz, Karl; Aweryn, Barbara

2016-12-01

The extent of ochratoxin A (OTA) contamination of domestically produced foods sold across Canada was determined from 2009 to 2014 with sampling and testing occurring each fiscal year. Cereal-based, fruit-based, and soy-based food samples (n = 6,857) were analyzed. Almost half of the samples (3,200; 47%) did not contain detectable concentrations of OTA. The remaining 3,657 samples contained OTA at 0.040 to 631 ng/g. Wheat, oats, milled products of other grains (such as rye and buckwheat), and to a lesser extent corn products and their derived foods were the most significant potential sources of OTA exposure for the Canadian population. Wine, grape juice, soy products, beer, dairy-based infant formula, and licorice candy were not significant contributors to OTA consumption. Spices had the highest OTA concentrations; but because so little is ingested, these foods are not considered to be a significant source of OTA. In contrast, infant formulas and cereals can be important dietary sources of OTA. Infant cereals containing oats and infant formulas containing soy had detectable concentrations of OTA, some of which exceeded the proposed Canadian guidelines. The prevalence and concentrations of OTA in major crops (wheat, corn, and oats) varied widely across years. Because these foods were purchased at retail stores, no information was available on the OTA concentrations in the raw materials, the storage conditions before purchase of the samples, or the origin of the ingredients (may include blends of raw materials from different years and/or different geographical regions of Canada); therefore, impact of these factors could not be assessed. Overall, 2.3% of the samples exceeded the proposed Canadian OTA regulatory limits and 2.7% exceeded the current European Union (EU) OTA regulatory limits. These results are consistent with a Health Canada exposure assessment published in 2010, despite the inclusion of a wider range of products and confirm the safety of foods widely available across Canada.

Morphology, spatial distribution, and concentration of flame retardants in consumer products and environmental dusts using scanning electron microscopy and Raman micro-spectroscopy.

PubMed

Wagner, Jeff; Ghosal, Sutapa; Whitehead, Todd; Metayer, Catherine

2013-09-01

We characterized flame retardant (FR) morphologies and spatial distributions in 7 consumer products and 7 environmental dusts to determine their implications for transfer mechanisms, human exposure, and the reproducibility of gas chromatography-mass spectrometry (GC-MS) dust measurements. We characterized individual particles using scanning electron microscopy/energy dispersive x-ray spectroscopy (SEM/EDS) and Raman micro-spectroscopy (RMS). Samples were screened for the presence of 3 FR constituents (bromine, phosphorous, non-salt chlorine) and 2 metal synergists (antimony and bismuth). Subsequent analyses of select samples by RMS enabled molecular identification of the FR compounds and matrix materials. The consumer products and dust samples possessed FR elemental weight percents of up to 36% and 31%, respectively. We identified 24 FR-containing particles in the dust samples and classified them into 9 types based on morphology and composition. We observed a broad range of morphologies for these FR-containing particles, suggesting FR transfer to dust via multiple mechanisms. We developed an equation to describe the heterogeneity of FR-containing particles in environmental dust samples. The number of individual FR-containing particles expected in a 1-mg dust sample with a FR concentration of 100ppm ranged from <1 to >1000 particles. The presence of rare, high-concentration bromine particles was correlated with decabromodiphenyl ether concentrations obtained via GC-MS. When FRs are distributed heterogeneously in highly concentrated dust particles, human exposure to FRs may be characterized by high transient exposures interspersed by periods of low exposure, and GC-MS FR concentrations may exhibit large variability in replicate subsamples. Current limitations of this SEM/EDS technique include potential false negatives for volatile and chlorinated FRs and greater quantitation uncertainty for brominated FR in aluminum-rich matrices. Copyright © 2013 Elsevier Ltd. All rights reserved.

Hypoglycin A Concentrations in Maple Tree Species in the Netherlands and the Occurrence of Atypical Myopathy in Horses.

PubMed

Westermann, C M; van Leeuwen, R; van Raamsdonk, L W D; Mol, H G J

2016-05-01

Atypical myopathy (AM) in horses is caused by the plant toxin hypoglycin A, which in Europe typically is found in the sycamore maple tree (Acer pseudoplatanus). Owners are concerned about whether their horses are in danger if they graze near maple trees. To measure hypoglycin A in the most common maple tree species in the Netherlands, and to determine whether concentration of toxin is a predictor of AM in horses. A total of 278 samples of maple tree leaves, sprouts, and seeds were classified by species. Mean concentrations of hypoglycin A were compared for the type of sample, the season and the occurrence of AM in the pasture (non-AM versus AM). Statistical analysis was performed using generalized a linear model (SPPS22). Almost all Acer pseudoplatanus samples contained hypoglycin A, with concentrations differing significantly among sources (P < .001). Concentrations were significantly higher in seeds from the AM group than in seeds from the non-AM group (856 ± 677 and 456 ± 358 mg/kg, respectively; P = .039). In sprouts and leaves this was not the case. Acer platanoides and Acer campestre samples did not contain detectable concentrations of hypoglycin A. Acer platanoides and campestre seem to be safe around paddocks and pastures, whereas almost all Acer pseudoplatanus samples contained hypoglycin A. In all AM cases, Acer pseudoplatanus was found. Despite significantly higher concentration of hypoglycin A in seeds of pastures where AM has occurred, individual prediction of AM cannot be made by measuring these concentrations because of the high standard deviation. Copyright © 2016 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

Reconnaissance geochemical survey of Al Jurdhawiyah and Wadi al Jarir quadrangles, sheets 25/42 D and 25/42 C, Kingdom of Saudia Arabia

USGS Publications Warehouse

Samater, Rashid M.

1983-01-01

A reconnaissance wadi-sediment geochemical survey was conducted in the Al Jurdhawiyah (sheet 28/42 D) and Wadi al Jarir (sheet 2G/42 C) quadrangles in order to identify anomalies potentially related to mineralized rock. Sieved bulk-sediment fractions and pan concentrates were created from the original samples collected from wadis in the two quadrangles. A semiquantitative 30-element spectrographic analysis was completed on both the sieved bulk-sediment fraction and the pan concentrate of each sample. The results were statistically analyzed in an attempt to identify anomalous regions. Anomaly threshold values were calculated for most elements; the threshold value of an element in a data set is defined as the geometric mean value plus two standard deviations. The Bald al Jimalah West tin-tungsten deposit (MODS 02661) in the southern part of the Al Jurdhawiyah quadrangle was identified by one pan-concentrate sample containing anomalous concentrations of tin and tungsten. Samples near the Bald al Jimalah East ancient lead-zinc-silver mines (MODS 00960) contain strongly anomalous concentrations of tin and lead and to a lesser extent of tungsten and copper. Both of these regions and other regions containing anomalous concentrations of certain elements are recommended for additional studies. A comparison of results obtained from sieved bulk-sediment fractions and pan concentrates indicates that the latter is the better medium for these geochemical investigations.

Chemometric evaluation of Cd, Co, Cr, Cu, Ni (inductively coupled plasma optical emission spectrometry) and Pb (graphite furnace atomic absorption spectrometry) concentrations in lipstick samples intended to be used by adults and children.

PubMed

Batista, Érica Ferreira; Augusto, Amanda dos Santos; Pereira-Filho, Edenir Rodrigues

2016-04-01

A method was developed for determining the concentrations of Cd, Co, Cr, Cu, Ni and Pb in lipstick samples intended to be used by adults and children using inductively coupled plasma optical emission spectrometry (ICP OES) and graphite furnace atomic absorption spectrometry (GF AAS) after treatment with dilute HNO3 and hot block. The combination of fractional factorial design and Desirability function was used to evaluate the ICP OES operational parameters and the regression models using Central Composite and Doehlert designs were calculated to stablish the best working condition for all analytes. Seventeen lipstick samples manufactured in different countries with different colors and brands were analyzed. Some samples contained high concentrations of toxic elements, such as Cr and Pb, which are carcinogenic and cause allergic and eczematous dermatitis. The maximum concentration detected was higher than the permissible safe limits for human use, and the samples containing these high metal concentrations were intended for use by children. Principal component analysis (PCA) was used as a chemometrics tool for exploratory analysis to observe the similarities between samples relative to the metal concentrations (a correlation between Cd and Pb was observed). Copyright © 2015 Elsevier B.V. All rights reserved.

Poly- and perfluoroalkyl substances in wastewater: Significance of unknown precursors, manufacturing shifts, and likely AFFF impacts.

PubMed

Houtz, Erika F; Sutton, Rebecca; Park, June-Soo; Sedlak, Margaret

2016-05-15

In late 2014, wastewater effluent samples were collected from eight treatment plants that discharge to San Francisco (SF) Bay in order to assess poly- and perfluoroalkyl substances (PFASs) currently released from municipal and industrial sources. In addition to direct measurement of twenty specific PFAS analytes, the total concentration of perfluoroalkyl acid (PFAA) precursors was also indirectly measured by adapting a previously developed oxidation assay. Effluent from six municipal treatment plants contained similar amounts of total PFASs, with highest median concentrations of PFHxA (24 ng/L), followed by PFOA (23 ng/L), PFBA (19 ng/L), and PFOS (15 ng/L). Compared to SF Bay municipal wastewater samples collected in 2009, the short chain perfluorinated carboxylates PFBA and PFHxA rose significantly in concentration. Effluent samples from two treatment plants contained much higher levels of PFASs: over two samplings, wastewater from one municipal plant contained an average of 420 ng/L PFOS and wastewater from an airport industrial treatment plant contained 560 ng/L PFOS, 390 ng/L 6:2 FtS, 570 ng/L PFPeA, and 500 ng/L PFHxA. The elevated levels observed in effluent samples from these two plants are likely related to aqueous film forming foam (AFFF) sources impacting their influent; PFASs attributable to both current use and discontinued AFFF formulations were observed. Indirectly measured PFAA precursor compounds accounted for 33%-63% of the total molar concentration of PFASs across all effluent samples and the PFAA precursors indicated by the oxidation assay were predominately short-chained. PFAS levels in SF Bay effluent samples reflect the manufacturing shifts towards shorter chained PFASs while also demonstrating significant impacts from localized usage of AFFF. Copyright © 2016 Elsevier Ltd. All rights reserved.

Assessment of subsurface chlorinated solvent contamination using tree cores at the front street site and a former dry cleaning facility at the Riverfront Superfund site, New Haven, Missouri, 1999-2003

USGS Publications Warehouse

Schumacher, John G.; Struckhoff, Garrett C.; Burken, Joel G.

2004-01-01

Tree-core sampling has been a reliable and inexpensive tool to quickly assess the presence of shallow (less than about 30 feet deep) tetrachloroethene (PCE) and trichloroethene (TCE) contamination in soils and ground water at the Riverfront Superfund Site. This report presents the results of tree-core sampling that was successfully used to determine the presence and extent of chlorinated solvent contamination at two sites, the Front Street site (operable unit OU1) and the former dry cleaning facility, that are part of the overall Riverfront Superfund Site. Traditional soil and ground-water sampling at these two sites later confirmed the results from the tree-core sampling. Results obtained from the tree-core sampling were used to design and focus subsequent soil and ground-water investigations, resulting in substantial savings in time and site assessment costs. The Front Street site is a small (less than 1-acre) site located on the Missouri River alluvium in downtown New Haven, Missouri, about 500 feet from the south bank of the Missouri River. Tree-core sampling detected the presence of subsurface PCE contamination at the Front Street site and beneath residential property downgradient from the site. Core samples from trees at the site contained PCE concentrations as large as 3,850 mg-h/kg (micrograms in headspace per kilogram of wet core) and TCE concentrations as large as 249 mg-h/kg. Soils at the Front Street site contained PCE concentrations as large as 6,200,000 mg/kg (micrograms per kilogram) and ground-water samples contained PCE concentrations as large as 11,000 mg/L (micrograms per liter). The former dry cleaning facility is located at the base of the upland that forms the south bank of the Missouri River alluvial valley. Tree-core sampling did not indicate the presence of PCE or TCE contamination at the former dry cleaning facility, a finding that was later confirmed by the analyses of soil samples collected from the site. The lateral extent of PCE contamination in trees was in close agreement with the extent of subsurface PCE contamination determined using traditional soil and ground-water sampling methods. Trees growing in soils containing PCE concentrations of 60 to 5,700 mg/kg or larger or overlying ground water containing PCE concentrations from 5 to 11,000 mg/L generally contained detectable concentrations of PCE. The depth to contaminated ground water was about 20 to 25 feet below the land surface. Significant quantitative relations [probability (p) values of less than 0.05 and correlation coefficient (r2) values of 0.88 to 0.90] were found between PCE concentrations in trees and subsurface soils between 4 and 16 feet deep. The relation between PCE concentrations in trees and underlying ground water was less apparent (r2 value of 0.17) and the poor relation is thought to be the result of equilibrium with PCE concentrations in soil and vapor in the unsaturated zone. Based on PCE concentrations detected in trees at the Front Street site and trees growing along contaminated tributaries in other operable units, and from field hydroponic experiments using hybrid poplar cuttings, analysis of tree-core samples appears to be able to detect subsurface PCE contamination in soils at levels of several hundred micrograms per liter or less and PCE concentrations in the range of 8 to 30 mg/L in ground water in direct contact with the roots. Loss of PCE from tree trunks by diffusion resulted in an exponential decrease in PCE concentrations with increasing height above the land surface in most trees. The rate of loss also appeared to be a function of the size and growth characteristics of the tree as some trees exhibited a linear loss with increasing height. Diffusional loss of PCE in small (0.5-inch diameter) trees was observed to occur at a rate more than 10 times larger than in trees 6.5 inches in diameter. Concentrations of PCE also exhibited directional variability around the tree trunks and concentration differe

Flow injection trace gas analysis method for on-site determination of organoarsenicals

DOEpatents

Aldstadt, III, Joseph H.

1997-01-01

A method for real-time determination of the concentration of Lewisite in the ambient atmosphere, the method includes separating and collecting a Lewisite sample from the atmosphere in a collection chamber, converting the collected Lewisite to an arsenite ion solution sample, pumping the arsenite ion containing sample to an electrochemical detector connected to the collection chamber, and electrochemically detecting the converted arsenite ions in the sample, whereby the concentration of arsenite ions detected is proportional to the concentration of Lewisite in the atmosphere.

Stability of methadone hydrochloride in 0.9% sodium chloride injection in single-dose plastic containers.

PubMed

Denson, D D; Crews, J C; Grummich, K W; Stirm, E J; Sue, C A

1991-03-01

The stability of methadone hydrochloride in 0.9% sodium chloride injection in flexible polyvinyl chloride containers was studied. Commercially available methadone hydrochloride 20 mg/mL and 25-mL single-dose bags of 0.9% sodium chloride injection were used. Six samples each were prepared at methadone hydrochloride concentrations of 1, 2, and 5 mg/mL. The solutions were stored at room temperature and were not protected from light. Immediately after preparation and after two, three, and four weeks of storage, each of the 18 samples was divided into three aliquots, each of which was analyzed in duplicate for methadone hydrochloride concentration by gas chromatography. There was less than 10% change in methadone hydrochloride concentration in any sample throughout the four-week study period. Methadone hydrochloride at concentrations of 1, 2, and 5 mg/mL prepared in commercially available flexible polyvinyl chloride containers of 0.9% sodium chloride injection and stored at room temperature without deliberate protection from light is stable for at least four weeks.

Ground-water quality in the central part of the Passaic River basin, northeastern New Jersey, 1959-88

USGS Publications Warehouse

Czarnik, T.S.; Kozinski, Jane

1994-01-01

Ground-water samples were collected from 71 wells screened in or open to three aquifers in the central part of the Passaic River basin during 1959-88. Water samples from aquifers in glacial sediments and aquifers in sedimentary and igneous bedrock of the Newark Supergroup were analyzed for major ions. Most samples were analyzed for metals, nutrients, and tritium; 38 samples were analyzed for purgeable organic compounds. Calcium and bicarbonate were the predominant ions in ground water in the study area. Ground water was dilute (median dissolved-solids concentration 239 milligrams per liter) and slightly basic (median pH 7.89). Concentrations of inorganic constituents were within U.S. Environmental Protection Agency (USEPA) primary drinking-water regulations. Concentrations of benzene, tetrachloroethylene, and trichloroethylene, however, were greater than USEPA primary drinking-water regulations in six samples. Ground-water samples from aquifers in sedimentary bedrock were enriched in barium, calcium, magnesium, strontium,and sulfate relative to samples form the other aquifers. Such ion enrichment can be attributed either to disolution of carbonate and sulfate-containing minerals or to human activities. Ground-water samples from two wells screened in glacial sediments near swamps contained sulfate in concentrations higher than the median for the aquifer. Sulfate enrichment could result from downward leaching of water enriched in sulfur from the decay of organic matter in the swamps, from the disolution of sulfate-containing minerals, or from human activities. No regional trends in the chemical composition of the ground water in the study area were identified. Sulfate concentrations in ground- water samples from the sedimentary bedrock tended to increase with decreasing altitude of the deepest opening of the well; the correlation coefficient for the ranks of sulfate concentration and the altitude of the deepest opening of the well for 17 pairs of data is -0.690. Concentrations of tritium were greater than the detection limit in 33 of 35 ground-water samples, indicating that most ground water in the study area is more recent than 1953.

Chlorinated pesticides in stream sediments from organic, integrated and conventional farms.

PubMed

Shahpoury, Pourya; Hageman, Kimberly J; Matthaei, Christoph D; Magbanua, Francis S

2013-10-01

To determine if current sheep/beef farming practices affect pesticide residues in streams, current-use and legacy chlorinated pesticides were quantified in 100 sediment samples from 15 streams on the South Island of New Zealand. The study involved five blocks of three neighboring farms, with each block containing farms managed by organic, integrated and conventional farming practices. Significantly higher concentrations of dieldrin, ∑ endosulfans, ∑ current-use pesticides, and ∑ chlorinated pesticides were measured in sediments from conventional farms compared to organic and integrated farms. However, streams in the latter two farming categories were not pesticide-free and sometimes contained relatively high concentrations of legacy pesticides. Comparison of measured pesticide concentrations with sediment quality guidelines showed that, regardless of farming practice, mean pesticide concentrations were below the recommended toxicity thresholds. However, up to 23% of individual samples contained chlorpyrifos, endosulfan sulfate, ∑ DDT, dieldrin, or ∑ chlordane concentrations above these thresholds. Copyright © 2013 Elsevier Ltd. All rights reserved.

Method for immunodiagnostic detection of dioxins at low concentrations

DOEpatents

Vanderlaan, Martin; Stanker, Larry H.; Watkins, Bruce E.; Petrovic, Peter; Gorbach, Siegbert

1995-01-01

A method is described for the use of monoclonal antibodies in a sensitive immunoassay for halogenated dioxins and dibenzofurans in industrial samples which contain impurities. Appropriate sample preparation and selective enzyme amplification of the immunoassay sensitivity permits detection of dioxin contaminants in industrial or environmental samples at concentrations in the range of a few parts per trillion.

Effect of erbium(III) oxide addition on thermal properties and crystallization behavior of some zinc-borate glasses

NASA Astrophysics Data System (ADS)

Borodi, G.; Bolundut, L. C.; Pascuta, P.

2017-12-01

The effect of replacing B2O3 with Er2O3 on the thermal properties and crystallization behaviour of B2O3-ZnO glasses were investigated by Differential Thermal Analysis (DTA) and X-ray Diffraction Analysis (XRD) measurements. DTA measurements reveal that the temperature of vitreous transition and the glass stability increase with the increasing in concentration the erbium ions added in the samples. The fragility index of the glasses increases also, when the dopant concentration from the studied samples increases. The glass was obtained from kinetically strong-glass-forming liquid (KS type glass). The most stable sample from the thermal point of view seems to be the sample that contains 10 mol% of Er2O3. The XRD patterns of the heat-treated samples at 860°C show new crystalline phases that contain erbium when the concentration of Er2O3 in the samples is higher than 3 mol%.

Mercury Methylation at Mercury Mines In The Humboldt River Basin, Nevada, USA

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

Gray, John E.; Crock, James G.; Lasorsa, Brenda K.

2002-12-01

Total Hg and methylmercury concentrations were measured in mine-waste calcines (retorted ore), sediment, and water samples collected in and around abandoned mercury mines in western Nevada to evaluate Hg methylation at the mines and in the Humboldt River basin. Mine-waste calcines contain total Hg concentrations as high as 14 000?g/g. Stream-sediment samples collected within 1 km of the mercury mines contain total Hg concentrations as high as 170?g/g, whereas stream sediments collected>5 km from the mines, and those collected from the Humboldt River and regional baseline sites, contain total Hg concentrations<0.5?g/g. Similarly, methylmercury concentrations in mine-waste calcines are locally asmore » high as 96 ng/g, but methylmercury contents in stream-sediments collected downstream from the mines and from the Humboldt River are lower, ranging from<0.05 to 0.95 ng/g. Stream-water samples collected below two mines studied contain total Hg concentrations ranging from 6 to 2000 ng/L, whereas total Hg in Humboldt River water was generally lower ranging from 2.1 to 9.0 ng/L. Methylmercury concentrations in the Humboldt River water were the lowest in this study (<0.02-0.27 ng/L). Although total Hg and methylmercury concentrations are locally high in mine-waste calcines, there is significant dilution of Hg and lower Hg methylation down gradient from the mines, especially in the sediments and water collected from the Humboldt River, which is> 8 km from any mercury mines. Our data indicate little transference of Hg and methylmercury from the sediment to the water column due to the lack of mine runoff in this desert climate.« less

PYRAMID ROADLESS AREA, CALIFORNIA.

USGS Publications Warehouse

Armstrong, Augustus K.; Scott, Douglas F.

1984-01-01

A geologic and mineral survey was conducted in the Pyramid Roadless Area, California. The area contains mineral showings, but no mineral-resource potential was identified during our studies. Three granodiorite samples on the west side of the roadless area contained weakly anomalous concentrations of uranium. Two samples of roof-pendant rocks, one metasedimentary rock and one metavolcanic rock, contain low concentrations of copper, and of copper and molybdenum, respectively. Although none was identified, the geologic terrane is permissive for mineral occurrences and large-scale, detailed geologic mapping of the areas of metasedimentary and metavolcanic roof pendants in the Pyramid Roadless Area could define a mineral-resource potential for tungsten and precious metals.

Oil-water separation property of polymer-contained wastewater from polymer-flooding oilfields in Bohai Bay, China.

PubMed

Chen, Hua-xing; Tang, Hong-ming; Duan, Ming; Liu, Yi-gang; Liu, Min; Zhao, Feng

2015-01-01

In this study, the effects of gravitational settling time, temperature, speed and time of centrifugation, flocculant type and dosage, bubble size and gas amount were investigated. The results show that the simple increase in settling time and temperature is of no use for oil-water separation of the three wastewater samples. As far as oil-water separation efficiency is concerned, increasing centrifugal speed and centrifugal time is highly effective for L sample, and has a certain effect on J sample, but is not valid for S sample. The flocculants are highly effective for S and L samples, and the oil-water separation efficiency increases with an increase in the concentration of inorganic cationic flocculants. There exist critical reagent concentrations for the organic cationic and the nonionic flocculants, wherein a higher or lower concentration of flocculant would cause a decrease in the treatment efficiency. Flotation is an effective approach for oil-water separation of polymer-contained wastewater from the three oilfields. The oil-water separation efficiency can be enhanced by increasing floatation agent concentration, flotation time and gas amount, and by decreasing bubble size.

Tritium monitor

DOEpatents

Chastagner, Philippe

1994-01-01

A system for continuously monitoring the concentration of tritium in an aqueous stream. The system pumps a sample of the stream to magnesium-filled combustion tube which reduces the sample to extract hydrogen gas. The hydrogen gas is then sent to an isotope separation device where it is separated into two groups of isotopes: a first group of isotopes containing concentrations of deuterium and tritium, and a second group of isotopes having substantially no deuterium and tritium. The first group of isotopes containing concentrations of deuterium and tritium is then passed through a tritium detector that produces an output proportional to the concentration of tritium detected. Preferably, the detection system also includes the necessary automation and data collection equipment and instrumentation for continuously monitoring an aqueous stream.

Tritium monitor

DOEpatents

Chastagner, P.

1994-06-14

A system is described for continuously monitoring the concentration of tritium in an aqueous stream. The system pumps a sample of the stream to magnesium-filled combustion tube which reduces the sample to extract hydrogen gas. The hydrogen gas is then sent to an isotope separation device where it is separated into two groups of isotopes: a first group of isotopes containing concentrations of deuterium and tritium, and a second group of isotopes having substantially no deuterium and tritium. The first group of isotopes containing concentrations of deuterium and tritium is then passed through a tritium detector that produces an output proportional to the concentration of tritium detected. Preferably, the detection system also includes the necessary automation and data collection equipment and instrumentation for continuously monitoring an aqueous stream. 1 fig.

Albumin adsorption onto surfaces of urine collection and analysis containers.

PubMed

Robinson, Mary K; Caudill, Samuel P; Koch, David D; Ritchie, James; Hortin, Glen; Eckfeldt, John H; Sandberg, Sverre; Williams, Desmond; Myers, Gary; Miller, W Greg

2014-04-20

Adsorption of albumin onto urine collection and analysis containers may cause falsely low concentrations. We added (125)I-labeled human serum albumin to urine and to phosphate buffered solutions, incubated them with 22 plastic container materials and measured adsorption by liquid scintillation counting. Adsorption of urine albumin (UA) at 5-6 mg/l was <0.9%; and at 90 mg/l was <0.4%. Adsorption was generally less at pH8 than pH5 but only 3 cases had p<0.05. Adsorption from 11 unaltered urine samples with albumin 5-333 mg/l was <0.8%. Albumin adsorption for the material with greatest binding was extrapolated to the surface areas of 100 ml and 2l collection containers, and to instrument sample cups and showed <1% change in concentration at 5 mg/l and <0.5% change at 20 mg/l or higher concentrations. Adsorption of albumin from phosphate buffered solutions (2-28%) was larger than that from urine. Albumin adsorption differed among urine samples and plastic materials, but the total influence of adsorption was <1% for all materials and urine samples tested. Adsorption of albumin from phosphate buffered solutions was larger than that from urine and could be a limitation for preparations used as calibrators. Copyright © 2014 Elsevier B.V. All rights reserved.

Study on Dicarboxylic Acids in Aerosol Samples with Capillary Electrophoresis

PubMed Central

Adler, Heidi; Sirén, Heli

2014-01-01

The research was performed to study the simultaneous detection of a homologous series of α, ω-dicarboxylic acids (C2–C10), oxalic, malonic, succinic, glutaric, adipic, pimelic, suberic, azelaic, and sebacic acids, with capillary electrophoresis using indirect UV detection. Good separation efficiency in 2,6-pyridinedicarboxylic acid as background electrolyte modified with myristyl trimethyl ammonium bromide was obtained. The dicarboxylic acids were ionised and separated within five minutes. For the study, authentic samples were collected onto dry cellulose membrane filters of a cascade impactor (12 stages) from outdoor spring aerosols in an urban area. Hot water and ultrasonication extraction methods were used to isolate the acids from membrane filters. Due to the low concentrations of acids in the aerosols, the extracts were concentrated with solid-phase extraction (SPE) before determination. The enrichment of the carboxylic acids was between 86 and 134% with sample pretreatment followed by 100-time increase by preparation of the sample to 50 μL. Inaccuracy was optimised for all the sample processing steps. The aerosols contained dicarboxylic acids C2–C10. Then, mostly they contained C2, C5, and C10. Only one sample contained succinic acid. In the study, the concentrations of the acids in aerosols were lower than 10 ng/m3. PMID:24729915

Simple transmission Raman measurements using a single multivariate model for analysis of pharmaceutical samples contained in capsules of different colors.

PubMed

Lee, Yeojin; Kim, Jaejin; Lee, Sanguk; Woo, Young-Ah; Chung, Hoeil

2012-01-30

Direct transmission Raman measurements for analysis of pharmaceuticals in capsules are advantageous since they can be used to determine active pharmaceutical ingredient (API) concentrations in a non-destructive manner and with much less fluorescence background interference from the capsules themselves compared to conventional back-scattering measurements. If a single calibration model such as developed from spectra simply collected in glass vials could be used to determine API concentrations of samples contained in capsules of different colors rather than constructing individual models for each capsule color, the utility of transmission measurements would be further enhanced. To evaluate the feasibility, transmission Raman spectra of binary mixtures of ambroxol and lactose were collected in a glass vial and a partial least squares (PLS) model for the determination of ambroxol concentration was developed. Then, the model was directly applied to determine ambroxol concentrations of samples contained in capsules of 4 different colors (blue, green, white and yellow). Although the prediction performance was slightly degraded when the samples were placed in blue or green capsules, due to the presence of weak fluorescence, accurate determination of ambroxol was generally achieved in all cases. The prediction accuracy was also investigated when the thickness of the capsule was varied. Copyright © 2011 Elsevier B.V. All rights reserved.

Lead and cadmium concentrations in mink from northern Idaho

USGS Publications Warehouse

Blus, L.J.; Henny, C.J.

1990-01-01

The purposes of this study were to determine concentrations of cadmium and lead in mink (Mustela vison) in northern Idaho, to discuss potential effects, and to determine whether levels have declined. Mink (skinned carcasses) from the Coeur d'Alene River system (northern Idaho) were ohtained from trappers during the 1981-82 (n = 17) and 1986-87 (n= 14) seasons. Livers of all eight mink from the uncontaminated North Fork contained low levels of lead; whereas, 9 of the 23 mink from lateral lakes adjoining the contaminated main stem, downstream from a mining-smelting complex, contained potentially hazardous lead levels (>5 ?g/g). Stomach contents of nine mink contained variahle concentrations of lead (0.15 to 51 ?g/g); samples from the main stem contained the highest values. No difference was detected in lead concentrations in livers of mink trapped from the lateral lakes in 1981-82 and 1986-87. Levels of cadmium were low in all samples, but lead levels were the highest ever recorded in mink. Our results suggest that metal pollution has probably led to localized declines in mink populations.

Metals and metalloids in Little Penguin (Eudyptula minor) prey, blood and faeces.

PubMed

Finger, Annett; Lavers, Jennifer L; Dann, Peter; Kowalczyk, Nicole D; Scarpaci, Carol; Nugegoda, Dayanthi; Orbell, John D

2017-04-01

Piscivorous species like the Little Penguin (Eudyptula minor) are particularly at risk of being negatively impacted by pollution due to their heightened exposure through aquatic food chains. Therefore, determining the concentration of heavy metals in the fish prey of seabirds is an essential component of assessing such risk. In this study, we report on arsenic, cadmium, mercury, lead and selenium concentrations in three fish species, which are known to comprise a substantial part of the diet of Little Penguins at the urban colony of St Kilda, Melbourne, Australia. Metal concentrations in the fish sampled were generally within the expected limits, however, arsenic and mercury were higher than reported elsewhere. Anchovy (Engraulis australis) and sandy sprat (Hyperlophus vittatus) contained higher Hg concentrations than pilchard (Sardinops sagax), while sandy sprat and pilchard contained more selenium. We present these findings together with metal concentrations in Little Penguin blood and faeces, sampled within weeks of the fish collection. Mercury concentrations were highest in the blood, while faeces and fish prey species contained similar concentrations of arsenic and lead, suggesting faeces as a primary route of detoxification for these elements. We also investigated paired blood - faecal samples and found a correlation for selenium only. Preliminary data from stable isotope ratios in penguin blood indicate that changes in penguin blood mercury concentrations cannot be explained by trophic changes in their diet alone, suggesting a variation of bioavailable Hg within this semi-enclosed bay. Copyright © 2017 Elsevier Ltd. All rights reserved.

Volatile Concentrations in Pyroclastic Obsidian: Two Case Studies

NASA Astrophysics Data System (ADS)

Wearn, K. M.; Cashman, K. V.; Wallace, P. J.

2002-12-01

Pyroclastic obsidian is abundant in fall deposits associated with Mt. Mazama's Cleetwood eruption and South Sister's Rock Mesa eruption. Measured concentrations of H2Ototal and CO2 in >300 obsidian samples from these two eruptions provide important information about both the style of degassing (open- vs. closed-system) and changes in eruptive conditions through the course of both eruptions. Obsidian clasts preserve a range of total H2O contents, with samples from lower stratigraphic levels displaying a wider range of water concentrations than those from the uppermost tephra layer sampled. All samples from the Cleetwood section contain <=1 wt% water, with those from the top of that deposit containing <0.4 wt%. Obsidian from the basal ash layer of the subsequent climactic eruption contains 0.1 - 0.8 wt% water. Obsidian fragments from the Rock Mesa eruption show a broader range in H2Ototal contents (from 0.1 to >3 wt%) than those from the Cleetwood eruption. At Rock Mesa, maximum total water contents generally decrease with increased stratigraphic height. However, this decrease is not strictly monotonic: fluctuations in maximum total water contents correspond to stratigraphic unit boundaries. In addition, the Rock Mesa event produced abundant obsidian with very low H2Ototal concentrations throughout the eruption. Dissolved molecular CO2 levels are below the detection limit in all of the Cleetwood and Mazama samples. This is not surprising, given the low initial CO2 measured in Cleetwood and Mazama melt inclusions by Bacon et al. (1992). CO2 concentrations in the Rock Mesa clasts range from <5 ppm to ~44 ppm, and are positively correlated with H2Ototal concentrations. Fluorine concentrations in Cleetwood and Mazama climactic obsidian clasts vary between ~510 and ~695 ppm, with climactic samples averaging slightly lower concentrations than Cleetwood samples. Fluorine concentrations in Rock Mesa obsidians are uniformly low (~300 to ~510 ppm). Chlorine contents of Cleetwood and Mazama climactic samples range from ~1400 ppm to ~1610 ppm. The Rock Mesa samples all contain less chlorine (~510 to ~1120 ppm) than the Cleetwood and climactic samples, and in the Rock Mesa obsidian, chlorine and total water are positively correlated. Stratigraphic variations in the volatile contents of pyroclastic obsidian support previous work suggesting that obsidian forms along the margins of the volcanic conduit and is eroded from the conduit walls by fragmenting magma. Both the Cleetwood and the Rock Mesa deposits indicate initial evacuation of shallow vanguard magma followed by a rapid increase in fragmentation depth. Both deposits also show a gradual decrease in the fragmentation depth through time, consistent with subsequent effusive activity in both cases. More puzzling is the apparent closed-system degassing trend defined by the H2O-CO2-Cl relations in the Rock Mesa obsidian samples, despite the loss of volatiles required for obsidian formation. This suggests that volatile data may also provide information on the relative time scales of volatile exsolution and loss and obsidian formation.

[Examination of analytical method for triphenyltin (TPT) and tributyltin (TBT) to revise the official methods based on "Act on the Control of Household Products Containing Harmful Substances"].

PubMed

Kawakami, Tsuyoshi; Isama, Kazuo; Nakashima, Harunobu; Yoshida, Jin; Ooshima, Tomoko; Ohno, Hiroyuki; Uemura, Hitoshi; Shioda, Hiroko; Kikuchi, Yoko; Matsuoka, Atsuko; Nishimura, Tetsuji

2012-01-01

The use of triphenyltin (TPT) and tributyltin (TBT) in some household products is banned by "Act on the Control of Household Products Containing Harmful Substances" in Japan. To revise the official analytical method, the method for detecting these organotin compounds was examined in six laboratories using a textile product, water-based adhesive, oil-based paint, which contained known amounts of TPT and TBT (0.1, 1.0, 10 μg/g). TPT and TBT were measured by GC-MS after ethyl-derivation with sodium tetraethylborate. The TBT recoveries in the samples were 70-120%. The TPT recoveries in the water-based adhesive samples were 80-110%, while its concentrations in the textile product and oil-based paint samples decreased because of dephenylation during storage. However, the precision of the method examined was satisfactory because most coefficients of variation for TPT and TBT in the samples were less than 10%. Furthermore, the revised method was able to detect concentrations lower than the officially regulated value. However, the sample matrix and the condition of analytical instrument might affect the estimated TPT and TBT concentrations. Therefore, the revised method may not be suitable for quantitative tests; rather, it can be employed to judge the acceptable levels of these organotin compounds by comparing the values of control sample containing regulated amounts of TPT and TBT with those for an unknown sample, with deuterated TPT and TBT as surrogate substances. It is desirable that TPT in textile and oil-based paint samples are analyzed immediately after the samples obtained because of the decomposition of TPT.

Frequent Cross-Resistance to Dapivirine in HIV-1 Subtype C-Infected Individuals after First-Line Antiretroviral Therapy Failure in South Africa.

PubMed

Penrose, Kerri J; Wallis, Carole L; Brumme, Chanson J; Hamanishi, Kristen A; Gordon, Kelley C; Viana, Raquel V; Harrigan, P Richard; Mellors, John W; Parikh, Urvi M

2017-02-01

A vaginal ring containing dapivirine (DPV) has shown moderate protective efficacy against HIV-1 acquisition, but the activity of DPV against efavirenz (EFV)- and nevirapine (NVP)-resistant viruses that could be transmitted is not well defined. We investigated DPV cross-resistance of subtype C HIV-1 from individuals on failing NVP- or EFV-containing antiretroviral therapy (ART) in South Africa. Plasma samples were obtained from individuals with >10,000 copies of HIV RNA/ml and with HIV-1 containing at least one non-nucleoside reverse transcriptase (NNRTI) mutation. Susceptibility to NVP, EFV, and DPV in TZM-bl cells was determined for recombinant HIV-1 LAI containing bulk-amplified, plasma-derived, full-length reverse transcriptase sequences. Fold change (FC) values were calculated compared with a composite 50% inhibitory concentration (IC 50 ) from 12 recombinant subtype C HIV-1 LAI plasma-derived viruses from treatment-naive individuals in South Africa. A total of 25/100 (25%) samples showed >500-FCs to DPV compared to treatment-naive samples with IC 50 s exceeding the maximum DPV concentration tested (132 ng/ml). A total of 66/100 (66%) samples displayed 3- to 306-FCs, with a median IC 50 of 17.6 ng/ml. Only 9/100 (9%) samples were susceptible to DPV (FC < 3). Mutations L100I and K103N were significantly more frequent in samples with >500-fold resistance to DPV compared to samples with a ≤500-fold resistance. A total of 91% of samples with NNRTI-resistant HIV-1 from individuals on failing first-line ART in South Africa exhibited ≥3-fold cross-resistance to DPV. This level of resistance exceeds expected plasma concentrations, but very high genital tract DPV concentrations from DPV ring use could block viral replication. It is critically important to assess the frequency of transmitted and selected DPV resistance in individuals using the DPV ring. Copyright © 2017 American Society for Microbiology.

Frequent Cross-Resistance to Dapivirine in HIV-1 Subtype C-Infected Individuals after First-Line Antiretroviral Therapy Failure in South Africa

PubMed Central

Penrose, Kerri J.; Wallis, Carole L.; Brumme, Chanson J.; Hamanishi, Kristen A.; Gordon, Kelley C.; Viana, Raquel V.; Harrigan, P. Richard; Mellors, John W.

2016-01-01

ABSTRACT A vaginal ring containing dapivirine (DPV) has shown moderate protective efficacy against HIV-1 acquisition, but the activity of DPV against efavirenz (EFV)- and nevirapine (NVP)-resistant viruses that could be transmitted is not well defined. We investigated DPV cross-resistance of subtype C HIV-1 from individuals on failing NVP- or EFV-containing antiretroviral therapy (ART) in South Africa. Plasma samples were obtained from individuals with >10,000 copies of HIV RNA/ml and with HIV-1 containing at least one non-nucleoside reverse transcriptase (NNRTI) mutation. Susceptibility to NVP, EFV, and DPV in TZM-bl cells was determined for recombinant HIV-1LAI containing bulk-amplified, plasma-derived, full-length reverse transcriptase sequences. Fold change (FC) values were calculated compared with a composite 50% inhibitory concentration (IC50) from 12 recombinant subtype C HIV-1LAI plasma-derived viruses from treatment-naive individuals in South Africa. A total of 25/100 (25%) samples showed >500-FCs to DPV compared to treatment-naive samples with IC50s exceeding the maximum DPV concentration tested (132 ng/ml). A total of 66/100 (66%) samples displayed 3- to 306-FCs, with a median IC50 of 17.6 ng/ml. Only 9/100 (9%) samples were susceptible to DPV (FC < 3). Mutations L100I and K103N were significantly more frequent in samples with >500-fold resistance to DPV compared to samples with a ≤500-fold resistance. A total of 91% of samples with NNRTI-resistant HIV-1 from individuals on failing first-line ART in South Africa exhibited ≥3-fold cross-resistance to DPV. This level of resistance exceeds expected plasma concentrations, but very high genital tract DPV concentrations from DPV ring use could block viral replication. It is critically important to assess the frequency of transmitted and selected DPV resistance in individuals using the DPV ring. PMID:27895013

An optical spot test for the detection of dopamine in human urine using stabilized in air lipid films.

PubMed

Nikolelis, Dimitrios P; Drivelos, Dimitrios A; Simantiraki, Maria G; Koinis, Spyros

2004-04-15

The present technique describes a simple, sensitive spot test for the rapid one-shot detection of dopamine in human urine using lipid films with incorporated resorcin[4]arene receptor that are synthesized by a chemical reaction with a methacrylate polymer on a glass fiber filter. The lipid films without the receptor provided fluorescence under a UV lamp. The use of the receptor in these films quenched this fluorescence, and the color became similar to that of the filters without the lipid films. A drop of dopamine or urine containing this stimulant provided a "switching on" of the fluorescence, which allows the rapid detection of this stimulant in human urine at 10(-8) M concentrations. The novelty of the present work is that it opens new routes in the field of biosensing, i.e., development of sensitive, rapid, and simple methods for detecting species based on the fluorescence of the lipid membranes on a polymer film, and provides a spot test technique for the rapid detection of dopamine. The effect of potent interferences including a wide range of compounds usually found in human urine (i.e., ascorbic aid, glucose, leucine, glycine, tartrate, citrate, bicarbonate, and caffeine) was examined using an aqueous buffered solution that contained the potent interference and dopamine at two lower concentration levels (i.e., 3 x 10(-8)-10(-8) M). The effect of proteins and lipids was also investigated at these two lower dopamine concentration levels in aqueous buffered solution. The results showed no interferences from all these constituents at concentrations usually found in human urine samples; for example, albumin up to 3.22 g/L concentration levels did not provide any interference (i.e., no fluorescence). A drop of urine containing this stimulant provided similar results, i.e., a "switching on" of the fluorescence that allows a technique for the rapid detection of this stimulant in human urine at 10(-8) M concentrations. The technique is not based on a calibration graph but is a semiquantitative method for the detection of dopamine in real samples of urine that can be complimentary to HPLC methods. The difference in color between the samples containing dopamine at concentration levels of 10(-8)-10(-7) M can be easily distinguished by naked eye and a digital camera. An increase of dopamine concentration from 10(-8) to 10(-7) M makes the color more blue whereas the color of the filters remains purple in the blank test (i.e., addition of a urine sample without dopamine or dopamine at concentration levels of 10(-9) M to the filters that contain the lipid membranes with incorporated receptor). The reproducibility of the method was checked in approximately 100 samples, and all of them were found to provide similar results. Note that it was also found that the colors remain stable in the samples containing dopamine for periods of more than two months.

Flow injection trace gas analysis method for on-site determination of organoarsenicals

DOEpatents

Aldstadt, J.H. III

1997-06-24

A method is described for real-time determination of the concentration of Lewisite in the ambient atmosphere, the method includes separating and collecting a Lewisite sample from the atmosphere in a collection chamber, converting the collected Lewisite to an arsenite ion solution sample, pumping the arsenite ion containing sample to an electrochemical detector connected to the collection chamber, and electrochemically detecting the converted arsenite ions in the sample, whereby the concentration of arsenite ions detected is proportional to the concentration of Lewisite in the atmosphere. 2 figs.

Real-Time PCR Assay To Detect Smallpox Virus

PubMed Central

Sofi Ibrahim, M.; Kulesh, David A.; Saleh, Sharron S.; Damon, Inger K.; Esposito, Joseph J.; Schmaljohn, Alan L.; Jahrling, Peter B.

2003-01-01

We developed a highly sensitive and specific assay for the rapid detection of smallpox virus DNA on both the Smart Cycler and LightCycler platforms. The assay is based on TaqMan chemistry with the orthopoxvirus hemagglutinin gene used as the target sequence. With genomic DNA purified from variola virus Bangladesh 1975, the limit of detection was estimated to be approximately 25 copies on both machines. The assay was evaluated in a blinded study with 322 coded samples that included genomic DNA from 48 different isolates of variola virus; 25 different strains and isolates of camelpox, cowpox, ectromelia, gerbilpox, herpes, monkeypox, myxoma, rabbitpox, raccoonpox, skunkpox, vaccinia, and varicella-zoster viruses; and two rickettsial species at concentrations mostly ranging from 100 fg/μl to 1 ng/μl. Contained within those 322 samples were variola virus DNA, obtained from purified viral preparations, at concentrations of 1 fg/μl to 1 ng/μl. On the Smart Cycler platform, 2 samples with false-positive results were detected among the 116 samples not containing variola virus tested; i.e., the overall specificity of the assay was 98.3%. On the LightCycler platform, five samples with false-positive results were detected (overall specificity, 95.7%). Of the 206 samples that contained variola virus DNA ranging in concentrations from 100 fg/μl to 1 ng/μl, 8 samples were considered negative on the Smart Cycler platform and 1 sample was considered negative on the LightCycler platform. Thus, the clinical sensitivities were 96.1% for the Smart Cycler instrument and 99.5% for the LightCycler instrument. The vast majority of these samples were derived from virus-infected cell cultures and variola virus-infected tissues; thus, the DNA material contained both viral DNA and cellular DNA. Of the 43 samples that contained purified variola virus DNA ranging in concentration from 1 fg/μl to 1 ng/μl, the assay correctly detected the virus in all 43 samples on both the Smart Cycler and the LightCycler platforms. The assay may be useful for the early detection of smallpox virus infections should such infections occur as a result of a deliberate or an accidental recurrence. PMID:12904397

Patulin surveillance in apple cider and juice marketed in Michigan.

PubMed

Harris, Kerri L; Bobe, Gerd; Bourquin, Leslie D

2009-06-01

Patulin is the most common mycotoxin found in apples and apple juices. The objective of this study was to determine the concentrations of patulin in (i) apple cider produced and marketed by Michigan apple cider mills during the fall seasons of 2002 to 2003 and 2003 to 2004 and (ii) apple juice and cider, including shelf-stable products, marketed in retail grocery stores in Michigan throughout 2005 and 2006. End product samples (n=493) obtained from 104 Michigan apple cider mills were analyzed for patulin concentration by using solid-phase extraction followed by high-performance liquid chromatography. Patulin was detected (> or =4 microg/liter) in 18.7% of all cider mill samples, with 11 samples (2.2%) having patulin concentrations of > or =50 microg/liter. A greater percentage of cider samples obtained from mills using thermal pasteurization contained detectable patulin (28.4%) than did those from mills using UV light radiation (13.5%) or no pathogen reduction treatment (17.0%). Among retail grocery store samples (n=159), 23% of apple juice and cider samples contained detectable patulin, with 18 samples (11.3%) having patulin concentrations of > or =50 microg/liter. The U.S. Food and Drug Administration (FDA) action level for patulin is 50 microg/kg. Some apple juice samples obtained from retail grocery stores had exceptionally high patulin concentrations, ranging up to 2700 microg/liter. Collectively, these results indicate that most apple cider and juice test samples from Michigan were below the FDA action level for patulin but that certain apple cider and juice processors have inadequate controls over patulin concentrations in final products. The industry, overall, should focus on improved quality of fruit used in juice production and improve culling procedures to reduce patulin concentrations.

Study on Gold and base metal occurrence in Uluwai Prospect, Western Latimojong Mountain, South Sulawesi

NASA Astrophysics Data System (ADS)

Maulana, Adi; Jaya, Asri; Imai, Akira

2018-02-01

Uluwai Prospect is located in the northern part of South Arm of Sulawesi along the eastern part of the Kalosi Fold Belt and Latimojong Mountain. The area is generally characterized by moderate to rugged topography area with elevation in the range of 700 to 1400 m above sea level in the mountainous complex called Latimojong Mountain Complex. The mineralization is characterized by a relatively simple sulphide ore mineral assemblage consists of pyrite, sphalerite and chalcopyrite. Samples were collected in areas showing abundant sulphide minerals where younger faults cut the bedding and foliation of country rocks. A number of silicified zones have been observed, as well as float material containing disseminated pyrite, chalcopyrite, and sphalerite with hematite, goethite and limonite. Some alteration types have been observed including sericitization, albitization, carbonatization and silisification. The samples collected indicated that the mineralisation is contained within metasedimentary (sandstone to mudstone) and greenschist. Geochemical analyses from 16 samples including 5 stream sediment samples indicated that the most promising mineralization occur in the prospect area are copper (Cu) and zinc (Zn). This is also supported by the abundance of chalcopyrite and sphalerite in some highly altered samples. Assaying of the collected samples revealed most of samples contain relatively low gold (Au) concentration. However, two samples contain 0.007 and 0.01 ppm of Au. In the mineralized area, Zn concentrations are up to 134 ppm, Cu up to 120 ppm and Pb up to 18 ppm and As up to 70 ppm. There is no clear relationship that exists between Au and the base metals except that one of the samples with highest Au values tend to have high Zn and As. This unclear pattern also shown by Cu, Pb and Zn. Base metal concentration in stream sediment samples show a relatively stable pattern than in rock samples. Arsenic tends to be elevated in base metal rich samples. Sb and Mo are relatively low in all sample type. However, Mo values will be high in the samples which contain highest Cu and Zn.

Radionuclides, inorganic constituents, organic compounds, and bacteria in water from selected wells and springs from the southern boundary of the Idaho National Engineering Laboratory to the Hagerman Area, Idaho, 1991

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

Bartholomay, R.C.; Edwards, D.D.; Campbell, L.J.

1993-11-01

The US Geological Survey and the Idaho Department of Water Resources, in response to a request from the US Department of Energy, sampled 18 sites as part of a long-term project to monitor water quality of the Snake River Plain aquifer from the southern boundary of the Idaho National Engineering Laboratory to the Hagerman area. Water samples were collected and analyzed for manmade pollutants and naturally occurring constituents. The samples were collected from six irrigation wells, seven domestic wells, two springs, one stock well, one dairy well, and one observation well. Quality assurance samples also were collected and analyzed. Themore » water samples were analyzed for selected radionuclides, inorganic constituents, organic compounds, and bacteria. None of the samples analyzed for radionuclides, inorganic constituents, or organic compounds exceeded the established maximum contaminant levels for drinking water. Most of the radionuclide and inorganic constituent concentrations exceeded their respective reporting levels. All the samples analyzed for dissolved organic carbon had concentrations that exceeded their reporting level. Concentrations of 1,1,1 -trichloroethane exceeded the reporting level in two water samples. Two samples and a quality assurance replicate contained reportable concentrations of 2, 4-D. One sample contained fecal coliform bacteria counts that exceeded established maximum contaminant levels for drinking water.« less

Vapor-phase concentrations of PAHs and their derivatives determined in a large city: correlations with their atmospheric aerosol concentrations.

PubMed

Barrado, Ana Isabel; García, Susana; Sevillano, Marisa Luisa; Rodríguez, Jose Antonio; Barrado, Enrique

2013-11-01

Thirteen PAHs, five nitro-PAHs and two hydroxy-PAHs were determined in 55 vapor-phase samples collected in a suburban area of a large city (Madrid, Spain), from January 2008 to February 2009. The data obtained revealed correlations between the concentrations of these compounds and a series of meteorological factors (e.g., temperature, atmospheric pressure) and physical-chemical factors (e.g., nitrogen and sulfur oxides). As a consequence, seasonal trends were observed in the atmospheric pollutants. A "mean sample" for the 14-month period would contain a total PAH concentration of 13835±1625 pg m(-3) and 122±17 pg m(-3) of nitro-PAHs. When the data were stratified by season, it emerged that a representative sample of the coldest months would contain 18900±2140 pg m(-3) of PAHs and 150±97 pg m(-3) of nitro-PAHs, while in an average sample collected in the warmest months, these values drop to 9293±1178 pg m(-3) for the PAHs and to 97±13 pg m(-3) for the nitro-PAHs. Total vapor phase concentrations of PAHs were one order of magnitude higher than concentrations detected in atmospheric aerosol samples collected on the same dates. Total nitro-PAH concentrations were comparable to their aerosol concentrations whereas vapor phase OH-PAHs were below their limits of the detection, indicating these were trapped in airborne particles. Copyright © 2013 Elsevier Ltd. All rights reserved.

Long-term stability of morphine, codeine, and 6-acetylmorphine in real-life whole blood samples, stored at -20°C.

PubMed

Høiseth, Gudrun; Fjeld, Bente; Burns, Margrete Larsen; Strand, Dag Helge; Vindenes, Vigdis

2014-06-01

Stability of drugs during storage is important in forensic toxicology. For the analytes detected after intake of heroin (6-acetylmorphine (6-AM), morphine and codeine), long-time stability in real life whole blood samples are studied in only a small number of cases. Whole blood post mortem (n=37) and whole blood samples from living persons (n=22) containing morphine and codeine as well as 6-AM in blood or urine were selected. All cases represented intake of heroin. All samples contained fluoride and were initially analysed and stored in normal conditions (-20°C) for 4-9 years. All samples were then reanalysed using the same analytical methods and the results were compared. For samples from living persons, the median change in concentration was -3.7% for morphine and -5.3% for codeine. For post mortem samples, the median change in concentration was -12% for morphine and -11% for codeine. Both for samples from living persons and post mortem samples, the decrease in the concentrations from the original analysis to reanalysis were statistically significant for morphine and codeine. Regarding 6-AM, all living samples were negative at reanalysis. For post mortem samples, four cases still tested positive for 6-AM at reanalysis with a median change in the concentrations of -81%. There was no significant change in the morphine to codeine concentration ratios neither for living nor post mortem samples. This study showed that in real life whole blood samples, the concentrations of morphine and codeine are relatively stable during long-term storage at -20°C. 6-AM on the other hand, shows a considerable decrease in concentrations that is important to consider when interpreting results from reanalyses of forensic cases. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Method and apparatus for processing a test sample to concentrate an analyte in the sample from a solvent in the sample

DOEpatents

Turner, Terry D.; Beller, Laurence S.; Clark, Michael L.; Klingler, Kerry M.

1997-01-01

A method of processing a test sample to concentrate an analyte in the sample from a solvent in the sample includes: a) boiling the test sample containing the analyte and solvent in a boiling chamber to a temperature greater than or equal to the solvent boiling temperature and less than the analyte boiling temperature to form a rising sample vapor mixture; b) passing the sample vapor mixture from the boiling chamber to an elongated primary separation tube, the separation tube having internal sidewalls and a longitudinal axis, the longitudinal axis being angled between vertical and horizontal and thus having an upper region and a lower region; c) collecting the physically transported liquid analyte on the internal sidewalls of the separation tube; and d) flowing the collected analyte along the angled internal sidewalls of the separation tube to and pass the separation tube lower region. The invention also includes passing a turbulence inducing wave through a vapor mixture to separate physically transported liquid second material from vaporized first material. Apparatus are also disclosed for effecting separations. Further disclosed is a fluidically powered liquid test sample withdrawal apparatus for withdrawing a liquid test sample from a test sample container and for cleaning the test sample container.

Method and apparatus for processing a test sample to concentrate an analyte in the sample from a solvent in the sample

DOEpatents

Turner, T.D.; Beller, L.S.; Clark, M.L.; Klingler, K.M.

1997-10-14

A method of processing a test sample to concentrate an analyte in the sample from a solvent in the sample includes: (a) boiling the test sample containing the analyte and solvent in a boiling chamber to a temperature greater than or equal to the solvent boiling temperature and less than the analyte boiling temperature to form a rising sample vapor mixture; (b) passing the sample vapor mixture from the boiling chamber to an elongated primary separation tube, the separation tube having internal sidewalls and a longitudinal axis, the longitudinal axis being angled between vertical and horizontal and thus having an upper region and a lower region; (c) collecting the physically transported liquid analyte on the internal sidewalls of the separation tube; and (d) flowing the collected analyte along the angled internal sidewalls of the separation tube to and pass the separation tube lower region. The invention also includes passing a turbulence inducing wave through a vapor mixture to separate physically transported liquid second material from vaporized first material. Apparatus is also disclosed for effecting separations. Further disclosed is a fluidically powered liquid test sample withdrawal apparatus for withdrawing a liquid test sample from a test sample container and for cleaning the test sample container. 8 figs.

Ochratoxin A in cereal-based baby foods: occurrence and safety evaluation.

PubMed

Beretta, B; De Domenico, R; Gaiaschi, A; Ballabio, C; Galli, C L; Gigliotti, C; Restani, P

2002-01-01

Ochratoxin A is a typical cereal contaminant with strong nephrotoxic activity. To estimate the quantity of ochratoxin A that can be taken in by a child in the weaning period, several samples of cereal-based baby foods were analysed. Although most samples analysed contained ochratoxin A in undetectable amounts or below the Italian legal limit of 0.5 microg kg(-1), some irregular products were found. In particular, the analyses of the 119 batches (338 samples) of baby foods considered indicated that: 20 batches (16.8%) contained detectable quantities of ochratoxin A and four of these (3.4% of the total) contained ochratoxin A above the Italian permitted value. All samples coming from agricultural practices based on integrated pest management contained undetectable amounts of ochratoxin A, while approximately 5% of batches coming from conventional and organic agricultural practices were above the legal limit. On the basis of the established provisional tolerable weekly intake (PTWI), there is no significant toxicological risk for a child who occasionally consumes a formula with ochratoxin concentration slightly above the permitted level. However, stricter controls have to be applied to reject the batches containing irregular concentrations of ochratoxin A.

Effect of various concentrations of butylated hydroxyanisole and butylated hydroxytoluene on freezing capacity of Turkman stallion sperm.

PubMed

Seifi-Jamadi, Afshin; Kohram, Hamid; Zareh-Shahne, Ahmad; Dehghanizadeh, Parvaneh; Ahmad, Ejaz

2016-07-01

The present study aimed to determine the effect of different concentrations of butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) on post-thaw stallion sperm quality. The ejaculates collected from four healthy mature Turkmen stallions were pooled and divided into eight aliquots. The samples were diluted with extenders containing different concentrations (0.5, 1 or 2mM/mL) of BHA or BHT. The positive control (PC) samples were diluted with extender containing 0.5% ethanol (v/v) whereas; the negative control (NC) samples were diluted with basic extender only. Semen samples were frozen according to a standard protocol. After thawing of samples, sperm motility, viability, membrane integrity, total abnormality and lipid peroxidation were assessed. The greatest (P<0.05) values for total sperm motility, viability and plasma membrane functionality and least values for malonedialdehyde (MDA) concentration were observed in samples supplemented either with 1mM BHT or 2mM BHA. However, the progressive motility was greater (P<0.05) only in samples treated with 2mM BHA. In conclusion, the use of 1mM BHT or 2mM BHA in extender improves the freezing capacity of stallion sperm by reducing oxidative stress during freeze-thaw process. Copyright © 2016 Elsevier B.V. All rights reserved.

Uranium hydrogeochemical and stream sediment reconnaissance of the Cortez NTMS Quadrangle, Colorado/Utah, including concentrations of forty-three additional elements

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

Warren, R.G.

1979-05-01

During the summers of 1976, 1977, and 1978, 598 water and 1657 sediment samples were collected from 1775 locations within the 19,600-km/sup 2/ area of the Cortez Quadrangle, Colorado and Utah. Water samples were collected from streams, springs, and wells; sediment samples were collected from stream channels (wet and dry) and from springs. Each water sample was analyzed for 13 elements, and each sediment sample was analyzed for 43 elements. Uranium concentrations in water samples range from below the detection limit of 0.02 to 241.47 ppB and have a median of 0.87 ppB and a mean of 3.80 ppB. Backgroundmore » uranium concentrations are 2 to 5 ppB in several nonmountainous regions but are much lower in mountainous areas, particularly in the northeastern portion of the quadrangle. Water samples containing high uranium concentrations (>20 ppB) generally are associated with high conductivities, high concentrations of other metallic elements, and geologic units, such as the Mancos shale, that are unfavorable for uranium mineralization. However, four ground-water samples exhibit high uranium concentrations without concomitant high conductivities or high concentrations of other metallic elements. Two of these samples were collected from sites in the Slick Rock U--V district, and two were collected in the Morrison formation in the southern portion of the quadrangle where large uranium deposits are not known. Water samples collected from the northwestern corner of the quadrangle uniformly exhibit background uranium values but generally contain high nickel concentrations. In this area, U--Cu (White Canyon-type) deposits are hosted primarily by the Shinarump member of the Chinle formation. Uranium concentrations in sediment samples range from 0.51 to 76.41 ppM and have a median of 2.76 ppM and a mean of 3.08 ppM. Background uranium and metallic element concentrations decrease to the southwest from the highest values in the northeastern portion of the quadrangle.« less

Fluoroacetate content of some species of the toxic Australian plant genus, Gastrolobium, and its environmental persistence.

PubMed

Twigg, L E; King, D R; Bowen, L H; Wright, G R; Eason, C T

1996-01-01

Gas chromatography confirmed the relatively high concentrations of fluoroacetate found in toxic Gastrolobiums, a genus of indigenous Australian plants. Fluoroacetate concentration in these plants ranged from 0.1 to 3875 micrograms/g (ppm) dry weight, with young leaves and flowers containing the highest concentrations. However, there was considerable intrastand variation between individual plants of at least two species with coefficients of variation ranging from 94% to 129%. Despite the high concentrations of fluoroacetate in many species, only one of nine soil samples collected from beneath these plants contained fluoroacetate. None of the 16 water samples collected from nearby streams and catchment dams contained fluoroacetate. This suggests that fluoroacetate does not persist in this environment. Fluoroacetate was also found in the genus Nemcia, and very low levels of fluoroacetate (ng/g) were detected in the foodstuffs, tea and guar gum. The latter indicates that other plant species may produce biologically insignificant amounts of fluoroacetate.

Concentration of platelets and growth factors in platelet-rich plasma from Goettingen minipigs.

PubMed

Jungbluth, Pascal; Grassmann, Jan-Peter; Thelen, Simon; Wild, Michael; Sager, Martin; Windolf, Joachim; Hakimi, Mohssen

2014-01-01

In minipigs little is known about the concentration of growth factors in plasma, despite their major role in several patho-physiological processes such as healing of fractures. This prompted us to study the concentration of platelets and selected growth factors in plasma and platelet-rich plasma (PRP) preparation of sixteen Goettingen minipigs. Platelet concentrations increased significantly in PRP in comparison to native blood plasma. Generally, significant increase in the concentration of all growth factors tested was observed in the PRP in comparison to the corresponding plasma or serum. Five of the plasma samples examined contained detectable levels of bone morphogenic protein 2 (BMP-2) whereas eleven of the plasma or serum samples contained minimal amounts of vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF-bb) respectively. On the other hand variable concentrations of bone morphogenic protein 7 (BMP-7) and transforming growth factor β1 (TGF-β1) were measured in all plasma samples. In contrast, all PRP samples contained significantly increased amounts of growth factors. The level of BMP-2, BMP-7, TGF-β1, VEGF and PDGF-bb increased by 17.6, 1.5, 7.1, 7.2 and 103.3 fold, in comparison to the corresponding non-enriched preparations. Moreover significant positive correlations were found between platelet count and the concentrations of BMP-2 (r=0.62, p<0.001), TGF-β1 (r=0.85, p<0.001), VEGF (r=0.46, p<0.01) and PDGF-bb (r=0.9, p<0.001). Our results demonstrate that selected growth factors are present in the platelet-rich plasma of minipigs which might thus serve as a source of autologous growth factors.

Effect of Carbon Nanotubes Upon Emissions From Cutting and Sanding Carbon Fiber-Epoxy Composites

PubMed Central

Heitbrink, William A.; Lo, Li-Ming

2015-01-01

Carbon nanotubes (CNTs) are being incorporated into structural composites to enhance material strength. During fabrication or repair activities, machining nanocomposites may release CNTs into the workplace air. An experimental study was conducted to evaluate the emissions generated by cutting and sanding on three types of epoxy-composite panels: Panel A containing graphite fibers, Panel B containing graphite fibers and carbon-based mat, and Panel C containing graphite fibers, carbon-based mat, and multi-walled CNTs. Aerosol sampling was conducted with direct-reading instruments, and filter samples were collected for measuring elemental carbon (EC) and fiber concentrations. Our study results showed that cutting Panel C with a band saw did not generate detectable emissions of fibers inspected by transmission electron microscopy but did increase the particle mass, number, and EC emission concentrations by 20% to 80% compared to Panels A and B. Sanding operation performed on two Panel C resulted in fiber emission rates of 1.9×108 and 2.8×106 fibers per second (f/s), while no free aerosol fibers were detected from sanding Panels A and B containing no CNTs. These free CNT fibers may be a health concern. However, the analysis of particle and EC concentrations from these same samples cannot clearly indicate the presence of CNTs, because extraneous aerosol generation from machining the composite epoxy material increased the mass concentrations of the EC. PMID:26478716

Prevalence and concentration of Salmonella on raw shelled peanuts in the United States.

PubMed

Calhoun, Stephen; Post, Laurie; Warren, Benjamin; Thompson, Sterling; Bontempo, Ann Rogers

2013-04-01

Recalls and/or outbreaks associated with Salmonella contamination in peanut-containing products were reported over the past several years. There are very limited data available on the prevalence and concentration of Salmonella on raw shelled peanuts in the United States. The objectives of this study were to estimate the prevalence of Salmonella on raw shelled peanuts in the United States and to estimate that concentration of Salmonella. Samples of Runner- and Virginia-type raw shelled peanuts from the 2008, 2009, and 2010 crop years were proportionately sampled from each growing region, based on 2007 production volume. Of 944 raw shelled peanut samples (375 g each), 22 (2.33%) were positive for Salmonella by the VIDAS Salmonella assay. Salmonella serovars identified in this study included Agona, Anatum, Braenderup, Dessau, Hartford, Meleagridis, Muenchen, Rodepoort, Tennessee, and Tornow. The concentration levels of Salmonella in positive samples, as determined by a most-probable-number assay, were <0.03 to 2.4 MPN/g. These data will be useful when designing and validating processes for the reduction or elimination of Salmonella in peanuts and/or peanut-containing products.

Distribution of volatile branched-chain fatty acids in various lamb tissues.

PubMed

Brennand, C P; Lindsay, R C

1992-01-01

Volatile fatty acids (C4-C11) including even-, odd-, and branched-chain members in lamb tissues were quantitatively analyzed. Volatile branched-chain fatty acids (BCFA) were more concentrated in subcutaneous adipose tissue samples (rump, shoulder, breast) than in perinepheric adipose or muscle tissues. Perinepheric adipose tissue contained relatively high quantities of n-chain, even-numbered fatty acids and very low levels of BCFA. Greater variation existed in fatty acid profiles among similar subcutaneous adipose tissues from different lambs than between samples of adipose tissue from different carcass sites from a given lamb sample. 4-Methyl- and 4-ethyloctanoic acids were present at concentrations greatly above threshold levels in all lamb fats tested, and thus upon hydrolysis would contribute species-related flavors to lamb. 4-Methylnonanoic concentrations in lamb fats ranged from nondetectable to greater than the threshold level, and therefore this compound would not always contribute to the species-related flavors of lamb. Lean meat samples contained very low concentrations of 4-methyl- and 4-ethyloctanoic acids. Copyright © 1992. Published by Elsevier Ltd.

Uranium hydrogeochemical and stream sediment reconnaissance of the Arminto NTMS quadrangle, Wyoming, including concentrations of forty-three additional elements

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

Morgan, T.L.

1979-11-01

During the summers of 1976 and 1977, 570 water and 1249 sediment samples were collected from 1517 locations within the 18,000-km/sup 2/ area of the Arminto NTMS quadrangle of central Wyoming. Water samples were collected from wells, springs, streams, and artifical ponds; sediment samples were collected from wet and dry streams, springs, and wet and dry ponds. All water samples were analyzed for 13 elements, including uranium, and each sediment sample was analyzed for 43 elements, including uranium and thorium. Uranium concentrations in water samples range from below the detection limit to 84.60 parts per billion (ppb) with a meanmore » of 4.32 ppb. All water sample types except pond water samples were considered as a single population in interpreting the data. Pond water samples were excluded due to possible concentration of uranium by evaporation. Most of the water samples containing greater than 20 ppb uranium grouped into six clusters that indicate possible areas of interest for further investigation. One cluster is associated with the Pumpkin Buttes District, and two others are near the Kaycee and Mayoworth areas of uranium mineralization. The largest cluster is located on the west side of the Powder River Basin. One cluster is located in the central Big Horn Basin and another is in the Wind River Basin; both are in areas underlain by favorable host units. Uranium concentrations in sediment samples range from 0.08 parts per million (ppm) to 115.50 ppm with a mean of 3.50 ppm. Two clusters of sediment samples over 7 ppm were delineated. The first, containing the two highest-concentration samples, corresponds with the Copper Mountain District. Many of the high uranium concentrations in samples in this cluster may be due to contamination from mining or prospecting activity upstream from the sample sites. The second cluster encompasses a wide area in the Wind River Basin along the southern boundary of the quadrangle.« less

Distribution, speciation, and transport of mercury in stream-sediment, stream-water, and fish collected near abandoned mercury mines in southwestern Alaska, USA

USGS Publications Warehouse

Gray, J.E.; Theodorakos, P.M.; Bailey, E.A.; Turner, R.R.

2000-01-01

Concentrations of total Hg, Hg (II), and methylmercury were measured in stream-sediment, stream-water, and fish collected downstream from abandoned mercury mines in south-western Alaska to evaluate environmental effects to surrounding ecosystems. These mines are found in a broad belt covering several tens of thousands of square kilometers, primarily in the Kuskokwim River basin. Mercury ore is dominantly cinnabar (HgS), but elemental mercury (Hg(o)) is present in ore at one mine and near retorts and in streams at several mine sites. Approximately 1400 t of mercury have been produced from the region, which is approximately 99% of all mercury produced from Alaska. These mines are not presently operating because of low prices and low demand for mercury. Stream-sediment samples collected downstream from the mines contain as much as 5500 ??g/g Hg. Such high Hg concentrations are related to the abundance of cinnabar, which is highly resistant to physical and chemical weathering, and is visible in streams below mine sites. Although total Hg concentrations in the stream-sediment samples collected near mines are high, Hg speciation data indicate that concentrations of Hg (II) are generally less than 5%, and methylmercury concentrations are less than 1% of the total Hg. Stream waters below the mines are neutral to slightly alkaline (pH 6.8-8.4), which is a result of the insolubility of cinnabar and the lack of acid- generating minerals such as pyrite in the deposits. Unfiltered stream-water samples collected below the mines generally contain 500-2500 ng/l Hg; whereas, corresponding stream-water samples filtered through a 0.45-??m membrane contain less than 50 ng/l Hg. These stream-water results indicate that most of the Hg transported downstream from the mines is as finely- suspended material rather than dissolved Hg. Mercury speciation data show that concentrations of Hg (II) and methylmercury in stream-water samples are typically less than 22 ng/l, and generally less than 5% of the total Hg. Muscle samples of fish collected downstream from mines contain as much as 620 ng/g Hg (wet wt.), of which 90-100% is methylmercury. Although these Hg concentrations are several times higher than that in fish collected from regional baseline sites, the concentration of Hg in fish is below the 1000 ng/g action level for edible fish established by the US Food and Drug Administration (FDA). Salmon contain less than 100 ng/g Hg, which are among the lowest Hg contents observed for fish in the study, and well below the FDA action level. (C) 2000 Elsevier Science B.V.

Presence and biological activity of antibiotics used in fuel ethanol and corn co-product production.

PubMed

Compart, D M Paulus; Carlson, A M; Crawford, G I; Fink, R C; Diez-Gonzalez, F; Dicostanzo, A; Shurson, G C

2013-05-01

Antibiotics are used in ethanol production to control bacteria from competing with yeast for nutrients during starch fermentation. However, there is no published scientific information on whether antibiotic residues are present in distillers grains (DG), co-products from ethanol production, or whether they retain their biological activity. Therefore, the objectives of this study were to quantify concentrations of various antibiotic residues in DG and determine whether residues were biologically active. Twenty distillers wet grains and 20 distillers dried grains samples were collected quarterly from 9 states and 43 ethanol plants in the United States. Samples were analyzed for DM, CP, NDF, crude fat, S, P, and pH to describe the nutritional characteristics of the samples evaluated. Samples were also analyzed for the presence of erythromycin, penicillin G, tetracycline, tylosin, and virginiamycin M1, using liquid chromatography and mass spectrometry. Additionally, virginiamycin residues were determined, using a U.S. Food and Drug Administration-approved bioassay method. Samples were extracted and further analyzed for biological activity by exposing the sample extracts to 10(4) to 10(7) CFU/mL concentrations of sentinel bacterial strains Escherichia coli ATCC 8739 and Listeria monocytogenes ATCC 19115. Extracts that inhibited bacterial growth were considered to have biological activity. Physiochemical characteristics varied among samples but were consistent with previous findings. Thirteen percent of all samples contained low (≤1.12 mg/kg) antibiotic concentrations. Only 1 sample extract inhibited growth of Escherichia coli at 10(4) CFU/mL, but this sample contained no detectable concentrations of antibiotic residues. No extracts inhibited Listeria monocytogenes growth. These data indicate that the likelihood of detectable concentrations of antibiotic residues in DG is low; and if detected, they are found in very low concentrations. The inhibition in only 1 DG sample by sentinel bacteria suggests that antibiotic residues in DG were inactivated during the production process or are present in sublethal concentrations.

Influence of finishing systems on hydrophilic and lipophilic oxygen radical absorbance capacity (ORAC) in beef.

PubMed

Wu, C; Duckett, S K; Neel, J P S; Fontenot, J P; Clapham, W M

2008-11-01

The aim of this research was to: (1) develop a reliable extraction procedure and assay to determine antioxidant activity in meat products, and (2) assess the effect of beef finishing system (forage-finished: alfalfa, pearl millet or mixed pastures vs. concentrate-finished) on longissimus muscle antioxidant activity. The effect of extraction method (ethanol concentration and extraction time), protein removal, and sample preparation method (pulverization or freeze drying) were first evaluated to develop an antioxidant assay for meat products. Beef extracts prepared with low ethanol concentrations (20%) demonstrated higher hydrophilic ORAC. Protein removal prior to extraction reduced hydrophilic ORAC values. Sample preparation method influenced both hydrophilic and lipophilic ORAC, with pulverized samples containing higher hydrophilic and lipophilic ORAC values. Beef cattle finishing system (Forage: alfalfa, pearl millet, or natural pasture vs. concentrates) had little impact on muscle hydrophilic ORAC, but muscle from forage finished beef contained greater lipophilic ORAC. In addition, broiling of steaks reduced hydrophilic ORAC.

Aquifer susceptibility in Virginia, 1998-2000

USGS Publications Warehouse

Nelms, David L.; Harlow, George E.; Plummer, Niel; Busenberg, Eurybiades

2003-01-01

The U.S. Geological Survey (USGS), in cooperation with the Virginia Department of Health, sampled water from 171 wells and springs across the Commonwealth of Virginia between 1998 and 2000 as part of the Virginia Aquifer Susceptibility study. Most of the sites sampled are public water supplies that are part of the comprehensive Source Water Assessment Program for the Commonwealth. The fundamental premise of the study was that the identification of young waters (less than 50 years) by multiple environmental tracers could be used as a guide for classifying aquifers in terms of susceptibility to contamination from near-surface sources. Environmental tracers, including chlorofluorocarbons (CFCs), sulfur hexafluoride (SF6), tritium (3H), and tritium/helium-3 (3H/3He), and carbon isotopes (14C and d13C) were used to determine the age of water discharging from wells and springs. Concentrations of CFCs greater than 5 picograms per kilogram and 3H concentrations greater than 0.6 tritium unit were used as thresholds to indicate that parts of the aquifer sampled have a component of young water and are, therefore, susceptible to near-surface contamination. Concentrations of CFCs exceeded the susceptibility threshold in 22 percent of the wells and in one spring sampled in the Coastal Plain regional aquifer systems. About 74 percent of the samples from wells with the top of the first water zone less than 100 feet below land surface exceeded the threshold values, and water supplies developed in the upper 100 feet of the Coastal Plain are considered to be susceptible to contamination from near-surface sources. The maximum depth to the top of the screened interval for wells that contained CFCs was less than 150 feet. Wells completed in the deep confined aquifers in the Coastal Plain generally contain water older than 1,000 years, as indicated by carbon-14 dating, and are not considered to be susceptible to contamination under natural conditions. All of the water samples from wells and springs in the fractured-rock terrains (the Appalachian Plateaus, Valley and Ridge, Blue Ridge, and Piedmont regional aquifer systems) contained concentrations of CFCs and 3H greater than one or both of the thresholds. Because all of the water samples exceeded at least one of the threshold values, young water is present throughout most of these regional aquifer systems; therefore, water supplies developed in these systems are susceptible to contamination from near-surface sources. No relation between well depth and presence of CFCs is evident from samples in the fractured-rock terrains. More than 95 percent of the samples for which the dating methods were applicable contained waters with apparent ages less than 35 years. About 5 percent of these samples, most of which were from the Blue Ridge and Piedmont regional aquifer systems, contained young waters with apparent ages of less than 5 years. Most of the samples from the Valley and Ridge Carbonate, Blue Ridge, and Piedmont regional aquifer systems had young water fractions of more than 50 percent, whereas samples from the Coastal Plain Shallow and Appalachian Plateaus regional aquifer systems contained less than 40 percent young waters. Concentrations of CFCs in excess of air-water equilibrium, which can indicate that nonatmospheric sources (such as sewage effluent) have introduced CFCs into the ground-water system, were measured in 6 and 48 percent of the water samples from the Coastal Plain and fractured-rock regional aquifer systems, respectively. The nitrate (NO3) concentrations greater than the USGS detection level of 0.05 milligrams per liter generally increase as the apparent age of the young water fraction decreases, with the highest NO3 concentrations for samples in which one or more of the CFCs are above modern atmospheric mixing ratios (commonly referred to as 'contaminated' for ground-water dating purposes). Most of the samples in which NO3 was detected w

[Correlation of Persistent Free Radicals, PCDD/Fs and Metals in Waste Incineration Fly Ash].

PubMed

Wang, Tian-jiao; Chen, Tong; Zhan, Ming-xiu; Guo, Ying; Li, Xiao-dong

2016-03-15

Environmentally persistent free radicals (EPFRs) are relatively highly stable and found in the formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Recent studies have concentrated on model dioxin formation reactions and there are few studies on actual waste incineration fly ash. In order to study EPFRs and the correlation with dioxins and heavy metals in waste incineration fly ash, the spins of EPFRs, concentration of PCDD/Fs and metals in samples from 6 different waste incinerators were detected. The medical waste incineration fly ash from Tianjin, municipal solid waste incineration fly ash from Jiangxi Province, black carbon and slag from municipal solid waste incinerator in Lanxi, Zhejiang Province, all contained EPFRs. Above all the signal in Tianjin sample was the strongest. Hydroxyl radicals, carbon-center radicals and semiquinone radicals were detected. Compared with other samples, Jiangxi fly ash had the highest toxic equivalent quantity (TEQ) of dioxins, up to 7.229 4 ng · g⁻¹. However, the dioxin concentration in the Tianjin sample containing the strongest EPFR signals was only 0.092 8 ng · g⁻¹. There was perhaps little direct numeric link between EPFRs and PCDD/Fs. But the spins of EPFRs in samples presented an increasing trend as the metal contents increased, especially with Al, Fe, Zn. The signal strength of radicals was purposed to be related to the metal contents. The concentration of Zn (0.813 7% ) in the Tianjin sample was the highest and this sample contained much more spins of oxygen-center radicals. We could presume the metal Zn had a greater effect on the formation of EPFRs, and was easier to induce the formation of radicals with a longer half-life period.

Cyanogenic glycosides in plant-based foods available in New Zealand.

PubMed

Cressey, Peter; Saunders, Darren; Goodman, Janet

2013-01-01

Cyanogenic glycosides occur in a wide range of plant species. The potential toxicity of cyanogenic glycosides arises from enzymatic degradation to produce hydrogen cyanide, which may result in acute cyanide poisoning and has also been implicated in the aetiology of several chronic diseases. One hundred retail foods were sampled and analysed for the presence of total hydrocyanic acid using an acid hydrolysis-isonicotinic/barbituric acid colourimetric method. Food samples included cassava, bamboo shoots, almonds and almond products, pome fruit products, flaxseed/linseed, stone fruit products, lima beans, and various seeds and miscellaneous products, including taro leaves, passion fruit, spinach and canned stuffed vine leaves. The concentrations of total hydrocyanic acid (the hydrocyanic acid equivalents of all cyanogenic compounds) found were consistent with or lower than concentrations reported in the scientific literature. Linseed/flaxseed contained the highest concentrations of total hydrocyanic acid of any of the analysed foods (91-178 mg kg(-1)). Linseed-containing breads were found to contain total hydrocyanic acid at concentrations expected from their linseed content, indicating little impact of processing on the total hydrocyanic acid content. Simulation modelling was used to assess the risk due to the total hydrocyanic acid in fruit juice and linseed-containing bread. 

Effect of white tea and xylitol on structure and properties of demineralized enamel and jawbone

NASA Astrophysics Data System (ADS)

Auerkari, EI; Kiranahayu, R.; Emerita, D.; Sumariningsih, P.; Sarita, D.; Adiwirya, MS; Suhartono, AW

2018-05-01

White tea and xylitol have been suggested as potential agents to combat dental caries and osteoporosis through enhanced remineralization. This investigation aimed to determine the effects of exposure to white tea with and without xylitol on the structure, composition and hardness of demineralized human dental enamel. For control, samples of untreated and demineralized enamel and samples of untreated rat jawbone were subjected to similar measurements. For demineralization, the enamel samples were immersed for two days at 50°C in an acetate solution (pH 4.0). All samples were then soaked for two weeks at 37°C in a solution containing three different concentrations of white tea, xylitol or both, and an optional addition of the remineralization ingredients including Ca, P and F. For enamel samples without preceding demineralization and without added remineralization ingredients, the results showed highest mean hardness after immersion in a solution containing both white tea and xylitol, practically independently of their applied concentration level. However, for demineralized enamel samples with added remineralization ingredients, the resulting mean hardness was also dependent on concentration of white tea and xylitol. With sufficient concentration, hardness was again higher for combined white tea and xylitol than for either of these used alone.

A surrogate method for comparison analysis of salivary concentrations of Xylitol-containing products

PubMed Central

Riedy, Christine A; Milgrom, Peter; Ly, Kiet A; Rothen, Marilynn; Mueller, Gregory; Hagstrom, Mary K; Tolentino, Ernie; Zhou, Lingmei; Roberts, Marilyn C

2008-01-01

Background Xylitol chewing gum has been shown to reduce Streptococcus mutans levels and decay. Two studies examined the presence and time course of salivary xylitol concentrations delivered via xylitol-containing pellet gum and compared them to other xylitol-containing products. Methods A within-subjects design was used for both studies. Study 1, adults (N = 15) received three xylitol-containing products (pellet gum (2.6 g), gummy bears (2.6 g), and commercially available stick gum (Koolerz, 3.0 g)); Study 2, a second group of adults (N = 15) received three xylitol-containing products (pellet gum, gummy bears, and a 33% xylitol syrup (2.67 g). For both studies subjects consumed one xylitol product per visit with a 7-day washout between each product. A standardized protocol was followed for each product visit. Product order was randomly determined at the initial visit. Saliva samples (0.5 mL to 1.0 mL) were collected at baseline and up to 10 time points (~16 min in length) after product consumption initiated. Concentration of xylitol in saliva samples was analyzed using high-performance liquid chromatography. Area under the curve (AUC) for determining the average xylitol concentration in saliva over the total sampling period was calculated for each product. Results In both studies all three xylitol products (Study 1: pellet gum, gummy bears, and stick gum; Study 2: pellet gum, gummy bears, and syrup) had similar time curves with two xylitol concentration peaks during the sampling period. Study 1 had its highest mean peaks at the 4 min sampling point while Study 2 had its highest mean peaks between 13 to 16 minutes. Salivary xylitol levels returned to baseline at about 18 minutes for all forms tested. Additionally, for both studies the total AUC for the xylitol products were similar compared to the pellet gum (Study 1: pellet gum – 51.3 μg.min/mL, gummy bears – 59.6 μg.min/mL, and stick gum – 46.4 μg.min/mL; Study 2: pellet gum – 63.0 μg.min/mL, gummy bears – 55.9 μg.min/mL, and syrup – 59.0 μg.min/mL). Conclusion The comparison method demonstrated high reliability and validity. In both studies other xylitol-containing products had time curves and mean xylitol concentration peaks similar to xylitol pellet gum suggesting this test may be a surrogate for longer studies comparing various products. PMID:18267030

Radon-222 in the ground water of Chester County, Pennsylvania

USGS Publications Warehouse

Senior, Lisa A.

1998-01-01

Radon-222 concentrations in ground water in 31 geologic units in Chester County, Pa., were measured in 665 samples collected from 534 wells from 1986 to 1997. Chester County is underlain by schists, gneisses, quartzites, carbonates, sandstones, shales, and other rocks of the Piedmont Physiographic Province. On average, radon concentration was measured in water from one well per 1.4 square miles, throughout the 759 square-mile county, although the distribution of wells was not even areally or among geologic units.The median concentration of radon-222 in ground water from the 534 wells was 1,400 pCi/L (picocuries per liter). About 89 percent of the wells sampled contained radon-222 at concentrations greater than 300 pCi/L, and about 11 percent of the wells sampled contained radon-222 at concentrations greater than 5,000 pCi/L. The highest concentration measured was 53,000 pCi/L. Of the geologic units sampled, the median radon-222 concentration in ground water was greatest (4,400 pCi/L) in the Peters Creek Schist, the second most areally extensive formation in the county. Significant differences in the radon-222 concentrations in ground water among geologic units were observed. Generally, concentrations in ground water in schists, quartzites, and gneisses were greater than in ground water in anorthosite, carbonates, and ultramafic rocks. The distribution of radon-222 in ground water is related to the distribution of uranium in aquifer materials of the various rock types.Temporal variability in radon-222 concentrations in ground water does not appear to be greater than about a factor of two for most (75 percent) of wells sampled more than once but was observed to range up to almost a factor of three in water from one well. In water samples from this well, seasonal variations were observed; the maximum concentrations were measured in the fall and the minimum in the spring.

Ground-water-quality data for selected wells in the Beaver Creek watershed, West Tennessee

USGS Publications Warehouse

Williams, S.D.

1996-01-01

In 1993 the U.S. Geological Survey, in cooperation with the Tennessee Department of Environment and Conservation (TDEC), began an investigation of the quality of ground water in the Beaver Creek watershed in West Tennessee. A total of 408 water samples were collected from 91 wells during 5 sampling periods in 1994. Water samples were analyzed for selected water-quality properties, fecal coliform and streptococci bacteria, nutrients, and major inorganic constituents. Selected well- construction data and information on potential sources of contamination were also collected for the 91 wells sampled. Nitrate concentrations (measured as NO3) ranged from a detection limit of 0.1 to 91 milligrams per liter (mg/L). Nitrate concentrations exceeding 13 mg/L were detected in 71 of the samples collected. Nitrate concentrations in water samples collected from three wells exceeded the TDEC primary drinking water standard of 44 mg/L for nitrate (measured as NO3). Nitrite (measured as NO2), ammonium (measured as NH4), and orthophosphate (measured as PO4) concentrations in samples were generally less than 0.1 mg/L (detection limit). Fecal coliform bacteria were detected in 33 of the 408 water samples collected. Samples from 21 of the 91 wells contained fecal coliform bacteria during one or more of the five sampling periods. Fecal streptococci bacteria were detected in 123 of the 408 samples. Samples from 59 wells contained fecal streptococci bacteria during one or more of the five sampling periods.

Inorganic analyses of Martian surface samples at the Viking landing sites

NASA Technical Reports Server (NTRS)

Clark, B. C.; Castro, A. J.; Rowe, C. D.; Baird, A. K.; Evans, P. H.; Rose, H. J., Jr.; Toulmin, P., III; Keil, K.; Kelliher, W. C.

1976-01-01

Elemental analyses of fines in the Martian regolith at two widely separated landing sites, Chryse Planitia and Utopia Planitia, produced remarkably similar results. At both sites, the uppermost regolith contains abundant Si and Fe, with significant concentrations of Mg, Al, S, Ca, and Ti. The S concentration is one to two orders of magnitude higher, and K (less than 0.25% by weight) is at least 5 times lower than the average for earth's crust. The trace elements Sr, Y, and possibly Zr have been detected at concentrations near or below 100 parts per million. Pebble-sized fragments sampled at Chryse contain more S than the bulk fines and are thought to be pieces of a sulfate-cemented duricrust.

Inorganic analyses of martian surface samples at the viking landing sites.

PubMed

Clark, B C; Baird, A K; Rose, H J; Toulmin, P; Keil, K; Castro, A J; Kelliher, W C; Rowe, C D; Evans, P H

1976-12-11

Elemental analyses of fines in the Martian regolith at two widely separated landing sites, Chryse Planitia and Utopia Planitia, produced remarkably similar results. At both sites, the uppermost regolith contains abundant Si and Fe, with significant concentrations of Mg, Al, S, Ca, and Ti. The S concentration is one to two orders of magnitude higher, and K(<0.25 percent by weight) is at least 5 times lower than the average for the earth's crust. The trace elements Sr, Y, and possibly Zr, have been detected at concentrations near or below 100 parts per million. Pebblesized fragments sampled at Chryse contain more S than the bulk fines, and are thought to be pieces of a sulfate-cemented duricrust.

A portable molecular-sieve-based CO2 sampling system for radiocarbon measurements

NASA Astrophysics Data System (ADS)

Palonen, V.

2015-12-01

We have developed a field-capable sampling system for the collection of CO2 samples for radiocarbon-concentration measurements. Most target systems in environmental research are limited in volume and CO2 concentration, making conventional flask sampling hard or impossible for radiocarbon studies. The present system captures the CO2 selectively to cartridges containing 13X molecular sieve material. The sampling does not introduce significant under-pressures or significant losses of moisture to the target system, making it suitable for most environmental targets. The system also incorporates a significantly larger sieve container for the removal of CO2 from chambers prior to the CO2 build-up phase and sampling. In addition, both the CO2 and H2O content of the sample gas are measured continuously. This enables in situ estimation of the amount of collected CO2 and the determination of CO2 flux to a chamber. The portable sampling system is described in detail and tests for the reliability of the method are presented.

A portable molecular-sieve-based CO2 sampling system for radiocarbon measurements.

PubMed

Palonen, V

2015-12-01

We have developed a field-capable sampling system for the collection of CO2 samples for radiocarbon-concentration measurements. Most target systems in environmental research are limited in volume and CO2 concentration, making conventional flask sampling hard or impossible for radiocarbon studies. The present system captures the CO2 selectively to cartridges containing 13X molecular sieve material. The sampling does not introduce significant under-pressures or significant losses of moisture to the target system, making it suitable for most environmental targets. The system also incorporates a significantly larger sieve container for the removal of CO2 from chambers prior to the CO2 build-up phase and sampling. In addition, both the CO2 and H2O content of the sample gas are measured continuously. This enables in situ estimation of the amount of collected CO2 and the determination of CO2 flux to a chamber. The portable sampling system is described in detail and tests for the reliability of the method are presented.

PCB-containing wood floor finish is a likely source of elevated PCBs in residents' blood, household air and dust: a case study of exposure

PubMed Central

Rudel, Ruthann A; Seryak, Liesel M; Brody, Julia G

2008-01-01

Background Polychlorinated biphenyls (PCBs) are persistent pollutants identified worldwide as human blood and breast milk contaminants. Because they bioaccumulate, consumption of meat, fish, and dairy products predicts human blood concentrations. PCBs were also used widely in building materials, including caulks and paints, but few studies have evaluated the contribution of these exposures to body burden. Methods In an earlier study, we detected PCBs in indoor air in 31% of 120 homes on Cape Cod, MA. Two of the homes had much higher concentrations than the rest, so we retested to verify the initial finding, evaluate blood PCB concentrations of residents, and identify the PCB source. Results Air and dust concentrations remained elevated over 5 years between initial and follow-up sampling. Blood serum concentrations of PCBs in residents of the homes were generally elevated above the 95th percentile of a representative sample of the US population. Serum concentrations in residents and air and dust concentrations were especially high in a home where a resident reported use of PCB-containing floor finish in the past, and where the floor of one room was sanded and refinished just prior to sample collection. Conclusion This case-study suggests that PCB residues in homes may be more significant contributors to overall exposure than diet for some people, and that use of a commercially-available PCB-containing wood floor finish in residences during the 1950s and 1960s is an overlooked but potentially important source of current PCB exposure in the general population. PMID:18201376

Geologic reconnaissance and geochemical sampling survey of molybdenum mineralization near Schiestler Peak, Temple Peak Quadrangle, Sublette County, Wyoming

USGS Publications Warehouse

Lee, G.K.; Antweiler, J.C.; Love, J.D.; Benedict, J.F.

1982-01-01

A brief geologic reconnaissance and geochemical survey of molybdenum mineralization near Schiestler Peak, Sublette County, Wyo., indicates that molybdenite occurs in this area as disseminations and blebs in granitic or quartz monzonitic rocks intruded by felsic dikes of similar composition. Samples of stream sediments, panned concentrates from stream sediments, soils, rocks, and water were collected in the geochemical survey. Analytical results show that in reconnaissance, panned concentrates are the best of the sample types used in this study to detect molybdenum mineralization. More detailed analysis of the distribution of the molybdenum is best achieved through the collection of rock samples. Hydrothermal alteration is generally not conspicuous in the study area; however, rock samples that contain molybdenite are usually slightly enriched in silver, copper, lead, and in several instances, gold. Conversely, there appear to be negative associations between molybdenum and zinc and between molybdenum and several of the rare-earth elements. Mo concentrations in the rock samples with no visible molybdenite range from undetectable at a sensitivity of 5 parts per million (ppm) to 700 ppm. Mo content in rock samples containing visible molybdenite ranges from 10 ppm to greater than 2,000 ppm. Stream-sediment values range from undetected to 15 ppm; panned concentrates from undetected to 15 ppm; soils from undetected to 20 ppm. Analyses of the water samples indicate Mo concentrations from 0.8 parts per billion (ppb) to 4.8 ppb. As currently understood, this deposit is not extensive or continuous, but drilling to provide information on the vertical extent of mineralization may alter this opinion.

Stability of selected volatile contact allergens in different patch test chambers under different storage conditions.

PubMed

Mose, Kristian F; Andersen, Klaus E; Christensen, Lars Porskjaer

2012-04-01

Patch test preparations of volatile substances may evaporate during storage, thereby giving rise to reduced patch test concentrations. To investigate the stability of selected acrylates/methacrylates and fragrance allergens in three different test chambers under different storage conditions. Petrolatum samples of methyl methacrylate (MMA), 2-hydroxyethyl methacrylate (2-HEMA), 2-hydroxypropyl acrylate (2-HPA), cinnamal and eugenol in patch test concentrations were stored in three different test chambers (IQ chamber™, IQ Ultimate™, and Van der Bend® transport container) at room temperature and in a refrigerator. The samples were analysed in triplicate with high-performance liquid chromatography. The decrease in concentration was substantial for all five allergens under both storage conditions in IQ chamber™ and IQ Ultimate™, with the exception of 2-HEMA during storage in the refrigerator. For these two chamber systems, the contact allergen concentration dropped below the stability limit in the following order: MMA, cinnamal, 2-HPA, eugenol, and 2-HEMA. In the Van der Bend® transport container, the contact allergens exhibited acceptable stability under both storage conditions, whereas MMA and 2-HPA required cool storage for maintenance of the limit. The Van der Bend® transport container was the best device for storage of samples of volatile contact allergens. © 2012 John Wiley & Sons A/S.

Factors affecting ANKOM™ fiber analysis of forage and browse varying in condensed tannin concentration.

PubMed

Terrill, Thomas H; Wolfe, Richard M; Muir, James P

2010-12-01

Browse species containing condensed tannins (CTs) are an important source of nutrition for grazing/browsing livestock and wildlife in many parts of the world, but information on fiber concentration and CT-fiber interactions for these plants is lacking. Ten forage or browse species with a range of CT concentrations were oven dried and freeze dried and then analyzed for ash-corrected neutral detergent fiber (NDFom) and corrected acid detergent fiber (ADFom) using separate samples (ADFSEP) and sequential NDF-ADF analysis (ADFSEQ) with the ANKOM™ fiber analysis system. The ADFSEP and ADFSEQ residues were then analyzed for nitrogen (N) concentration. Oven drying increased (P < 0.05) fiber concentrations with some species, but not with others. For high-CT forage and browse species, ADFSEP concentrations were greater (P < 0.05) than NDFom values and approximately double the ADFSEQ values. Nitrogen concentration was greater (P < 0.05) in ADFSEP than ADFSEQ residues, likely due to precipitation with CTs. Sequential NDF-ADF analysis gave more realistic values and appeared to remove most of the fiber residue contaminants in CT forage samples. Freeze drying samples with sequential NDF-ADF analysis is recommended in the ANKOM™ fiber analysis system with CT-containing forage and browse species. Copyright © 2010 Society of Chemical Industry.

Method for detecting coliform organisms

NASA Technical Reports Server (NTRS)

Nishioka, K.; Nibley, D. A.; Jeffers, E. L.; Brooks, R. L. (Inventor)

1983-01-01

A method and apparatus are disclosed for determining the concentration of coliform bacteria in a sample. The sample containing the coliform bacteria is cultured in a liquid growth medium. The cultured bacteria produce hydrogen and the hydrogen is vented to a second cell containing a buffer solution in which the hydrogen dissolves. By measuring the potential change in the buffer solution caused by the hydrogen, as a function of time, the initial concentration of bacteria in the sample is determined. Alternatively, the potential change in the buffer solution can be compared with the potential change in the liquid growth medium to verify that the potential change in the liquid growth medium is produced primarily by the hydrogen gas produced by the coliform bacteria.

40 CFR Appendix B to Part 136 - Definition and Procedure for the Determination of the Method Detection Limit-Revision 1.11

Code of Federal Regulations, 2013 CFR

2013-07-01

... that the analyte concentration is greater than zero and is determined from analysis of a sample in a given matrix containing the analyte. Scope and Application This procedure is designed for applicability to a wide variety of sample types ranging from reagent (blank) water containing analyte to wastewater...

40 CFR Appendix B to Part 136 - Definition and Procedure for the Determination of the Method Detection Limit-Revision 1.11

Code of Federal Regulations, 2014 CFR

2014-07-01

... that the analyte concentration is greater than zero and is determined from analysis of a sample in a given matrix containing the analyte. Scope and Application This procedure is designed for applicability to a wide variety of sample types ranging from reagent (blank) water containing analyte to wastewater...

40 CFR Appendix B to Part 136 - Definition and Procedure for the Determination of the Method Detection Limit-Revision 1.11

Code of Federal Regulations, 2011 CFR

2011-07-01

... that the analyte concentration is greater than zero and is determined from analysis of a sample in a given matrix containing the analyte. Scope and Application This procedure is designed for applicability to a wide variety of sample types ranging from reagent (blank) water containing analyte to wastewater...

Trace-Element Concentrations in Northwest Africa 032

NASA Technical Reports Server (NTRS)

Korotev, R. L.; Jolliff, B. L.; Wang, A.; Gillis, J. J.; Haskin, L. A.; Fagan, T. J.; Taylor, G. J.; Keil, K.

2001-01-01

Trace-element concentrations (INAA) are presented for four samples of the NWA 032 lunar meteorite. The mare basalt has a moderately high Th concentration (1.9 ppm) and a higher Th/REE ratio than any other known mare basalt. Additional information is contained in the original extended abstract.

Albumin adsorption onto surfaces of urine collection and analysis containers☆

PubMed Central

Robinson, Mary K.; Caudill, Samuel P.; Koch, David D.; Ritchie, James; Hortin, Glen; Eckfeldt, John H.; Sandberg, Sverre; Williams, Desmond; Myers, Gary; Miller, W. Greg

2017-01-01

Background Adsorption of albumin onto urine collection and analysis containers may cause falsely low concentrations. Methods We added 125I-labeled human serum albumin to urine and to phosphate buffered solutions, incubated them with 22 plastic container materials and measured adsorption by liquid scintillation counting. Results Adsorption of urine albumin (UA) at 5–6 mg/l was <0.9%; and at 90 mg/l was <0.4%. Adsorption was generally less at pH 8 than pH 5 but only 3 cases had p <0.05. Adsorption from 11 unaltered urine samples with albumin 5–333 mg/l was <0.8%. Albumin adsorption for the material with greatest binding was extrapolated to the surface areas of 100 ml and 2 l collection containers, and to instrument sample cups and showed <1% change in concentration at 5 mg/l and <0.5% change at 20 mg/l or higher concentrations. Adsorption of albumin from phosphate buffered solutions (2–28%) was larger than that from urine. Conclusions Albumin adsorption differed among urine samples and plastic materials, but the total influence of adsorption was <1% for all materials and urine samples tested. Adsorption of albumin from phosphate buffered solutions was larger than that from urine and could be a limitation for preparations used as calibrators. PMID:24513540

Atmospheric CO2 Concentrations from Aircraft for 1972-1981, CSIRO Monitoring Program

DOE Data Explorer

Beardsmore, David J. [Commonwealth Scientific and Industrial Research Organization (CSIRO), Victoria, Australia; Pearman, Graeme I. [Commonwealth Scientific and Industrial Research Organization (CSIRO), Victoria, Australia

2012-01-01

From 1972 through 1981, air samples were collected in glass flasks from aircraft at a variety of latitudes and altitudes over Australia, New Zealand, and Antarctica. The samples were analyzed for CO2 concentrations with nondispersive infrared gas analysis. The resulting data contain the sampling dates, type of aircraft, flight number, flask identification number, sampling time, geographic sector, distance in kilometers from the listed distance measuring equipment (DME) station, station number of the radio navigation distance measuring equipment, altitude of the aircraft above mean sea level, sample analysis date, flask pressure, tertiary standards used for the analysis, analyzer used, and CO2 concentration. These data represent the first published record of CO2 concentrations in the Southern Hemisphere expressed in the WMO 1981 CO2 Calibration Scale and provide a precise record of atmospheric CO2 concentrations in the troposphere and lower stratosphere over Australia and New Zealand.

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

Morgan, T.L.; George, W.E.; Hensley, W.K.

As part of the Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) of the National Uranium Resource Evaluation (NURE) sponsored by the US Department of Energy (DOE), the Los Alamos Scientific Laboratory (LASL) conducted a detailed hydrogeochemical survey of well waters in a 4250-km/sup 2/ area near Pie Town in west-central New Mexico. A total of 300 well samples was collected and analyzed for uranium and 23 other elements. The results of these analyses and carbonate and bicarbonate ion concentrations are presented in the Appendixes of this report. Uranium concentrations range from below the detection limit of 0.02 parts per billion (ppB)more » to 293.18 ppB and average 8.71 ppB. Samples containing high levels of uranium were collected from the Largo Creek valley west of Quemado, from a small area about 6 km east of Quemado, from a small area surrounding Pie Town, and from scattered locations in the area surrounding Adams Diggings north of Pie Town. Most of the samples containing high uranium concentrations were collected from wells associated with the volcanic sedimentary facies of the Datil formation. This formation is a likely source of mobile uranium that may be precipitating in the underlying Baca formation, a known uranium host unit. Bicarbonate ion concentration, while proportional to uranium concentration in some cases, is not a strong controlling factor in the uranium concentrations in samples from this area.« less

Circular birefringence/dichroism measurement of optical scattering samples using amplitude-modulation polarimetry

NASA Astrophysics Data System (ADS)

Liu, Wei-Chun; Lo, Yu-Lung; Phan, Quoc-Hung

2018-03-01

A method is proposed for extracting the circular birefringence (CB), circular dichroism (CD) and depolarization (Dep) properties of optical scattering samples using an amplitude-modulation polarimetry technique. The validity of the proposed method is demonstrated by extracting the CB property of pure glucose aqueous samples, the CB/Dep properties of glucose solutions containing 0.02% lipofundin particles, and the CD/Dep properties of chlorophyllin solutions containing suspended polystyrene microspheres. The results show that the proposed technique has the ability to detect pure glucose with a resolution of 66 mg/dL over a concentration range of 0-500 mg/dL. Moreover, the glucose concentration of the CB/Dep samples can be detected over the same range with a resolution of 168 mg/dL. Finally, the chlorophyllin concentration of the CD/Dep sample can be detected over the range of 0-200 μg/dL with a resolution of 6.5 × 10-5. In general, the results show that the proposed technique provides a reliable and accurate means of measuring the CB/CD properties of optical samples with scattering effects, and thus has significant potential for biological sensing applications.

Saharan dust - A carrier of persistent organic pollutants, metals and microbes to the Caribbean?

USGS Publications Warehouse

Garrison, V.H.; Foreman, W.T.; Genualdi, S.; Griffin, Dale W.; Kellogg, C.A.; Majewski, M.S.; Mohammed, A.; Ramsubhag, A.; Shinn, E.A.; Simonich, S.L.; Smith, G.W.

2006-01-01

An international team of scientists from government agencies and universities in the United States, U.S. Virgin Islands (USVI), Trinidad & Tobago, the Republic of Cape Verde, and the Republic of Mali (West Africa) is working together to elucidate the role Saharan dust may play in the degradation of Caribbean ecosystems. The first step has been to identify and quantify the persistent organic pollutants (POPs), trace metals, and viable microorganisms in the atmosphere in dust source areas of West Africa, and in dust episodes at downwind sites in the eastern Atlantic (Cape Verde) and the Caribbean (USVI and Trinidad & Tobago). Preliminary findings show that air samples from Mali contain a greater number of pesticides, polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) and in higher concentrations than the Caribbean sites. Overall, POP concentrations were similar in USVI and Trinidad samples. Trace metal concentrations were found to be similar to crustal composition with slight enrichment of lead in Mali. To date, hundreds of cultureable micro-organisms have been identified from Mali, Cape Verde, USVI, and Trinidad air samples. The sea fan pathogen, Aspergillus sydowii, has been identified in soil from Mali and in air samples from dust events in the Caribbean. We have shown that air samples from a dust-source region contain orders of magnitude more cultureable micro-organisms per volume than air samples from dust events in the Caribbean, which in turn contain 3-to 4-fold more cultureable microbes than during non-dust conditions.

VOCs, pesticides, nitrate, and their mixtures in groundwater used for drinking water in the United States

USGS Publications Warehouse

Squillace, P.J.; Scott, J.C.; Moran, M.J.; Nolan, B.T.; Kolpin, D.W.

2002-01-01

Samples of untreated groundwater from 1255 domestic drinking-water wells and 242 public supply wells were analyzed as part of the National Water-Quality Assessment Program of the U.S. Geological Survey between 1992 and 1999. Wells were sampled to define the regional quality of the groundwater resource and, thus, were distributed geographically across large aquifers, primarily in rural areas. For each sample, as many as 60 volatile organic compounds (VOCs), 83 pesticides, and nitrate were analyzed. On the basis of previous studies, nitrate concentrations as nitrogen ≥3 mg/L were considered to have an anthropogenic origin. VOCs were detected more frequently (44%) than pesticides (38%) or anthropogenic nitrate (28%). Seventy percent of the samples contained at least one VOC, pesticide, or anthropogenic nitrate; 47% contained at least two compounds; and 33% contained at least three compounds. The combined concentrations of VOCs and pesticides ranged from about 0.001 to 100 μg/L, with a median of 0.02 μg/L. Water from about 12% of the wells contained one or more compounds that exceeded U.S. Environmental Protection Agency drinking-water standards or human health criteria, primarily because of nitrate concentrations exceeding the maximum contaminant level in domestic wells. A mixture is defined as a unique combination of two or more particular compounds, regardless of the presence of other compounds that may occur in the same sample. There were 100 mixtures (significantly associated with agricultural land use) that had a detection frequency between 2% and 19%. There were 302 mixtures (significantly associated with urban land use) that had a detection frequency between 1% and <2%. Only 14 compounds (seven VOCs, six pesticides, and nitrate) contributed over 95% of the detections in these 402 mixtures; however, most samples with these mixtures also contain a variety of other compounds.

Effect of dietary calcium concentrations in low non-phytate phosphorus diets containing phytase on growth performance, bone mineralization, litter quality, and footpad dermatitis incidence in growing broiler chickens.

PubMed

Kim, Jong Hyuk; Jung, Hyunjung; Pitargue, Franco Martinez; Han, Gi Ppeum; Choi, Hyeon Seok; Kil, Dong Yong

2017-07-01

An experiment was conducted to investigate the effect of dietary Ca concentrations in low non-phytate phosphorus (NPP) diets containing phytase on growth performance, bone mineralization, litter quality, and footpad dermatitis (FPD) incidence in growing broiler chickens. A total of 1,800 21-day-old Ross 308 growing broiler chickens were allotted to 1 of 6 dietary treatments with 6 replicated cages. Six diets were formulated to provide increasing Ca concentrations of 4.0, 5.0, 6.0, 7.0, 8.0, or 9.0 g/kg in diets. The concentrations of NPP in all diets were maintained at 3.0 g/kg, and phytase was supplemented to all diets at the level of 1,000 fytase units (FTU)/kg. At the end of the 14-d feeding trial, birds were euthanized for tibia sampling, and litter samples were collected from 3 areas in the cage. The FPD incidence was measured based on a 6-point scoring system. Dietary Ca concentrations had no effect on growth performance of growing broiler chickens. However, a tendency (linear, p = 0.05) for decreased feed efficiency was observed as dietary Ca concentrations were increased. The concentrations of Ca and P in the tibia of broiler chickens increased (linear and quadratic, p<0.01) with increasing Ca concentrations in low NPP diets containing phytase. Litter pH, moisture, and N contents were not affected by increasing Ca concentrations in low NPP diets containing phytase. However, a tendency (quadratic, p = 0.10) for increased FPD incidence with increasing dietary Ca concentrations was observed. Dietary Ca concentrations from 4.0 to 9.0 g/kg in low NPP diets containing phytase have little effects on growth performance of growing broiler chickens. However, Ca and P concentrations in the tibia are decreased if dietary Ca concentrations are less than 5.0 g/kg. The FPD incidence for growing broiler chickens may be decreased if less than 9.0 g/kg of Ca is included in diets.

Plasma corticosterone and thyroxine concentrations during chronic ingestion of crude oil in mallard ducks (Anas platyrhynchos)

USGS Publications Warehouse

Rattner, B.A.; Eastin, W.C.

1981-01-01

1. Blood samples were collected from mallard ducks after 6, 12, and 18 weeks of dietary exposure to mash containing 0.015%, 0.150%, and 1.500% crude oil.2. Plasma corticosterone concentrations in ducks fed mash containing 0.150% or 1.500% Alaskan Prudhoe Bay crude oil were uniformly depressed when compared to values in untreated control birds.3. Plasma thyroxine concentration was not altered in ducks chronically exposed to crude oil.4. The observed alteration in corticosterone concentration could reduce tolerance to temperature and dietary fluctuations in the environment.

A single-blind controlled study of electrocautery and ultrasonic scalpel smoke plumes in laparoscopic surgery.

PubMed

Fitzgerald, J Edward F; Malik, Momin; Ahmed, Irfan

2012-02-01

Surgical smoke containing potentially carcinogenic and irritant chemicals is an inevitable consequence of intraoperative energized dissection. Different energized dissection methods have not been compared directly in human laparoscopic surgery or against commonly encountered pollutants. This study undertook an analysis of carcinogenic and irritant volatile hydrocarbon concentrations in electrocautery and ultrasonic scalpel plumes compared with cigarette smoke and urban city air control samples. Once ethical approval was obtained, gas samples were aspirated from the peritoneal cavity after human laparoscopic intraabdominal surgery solely using either electrocautery or ultrasonic scalpels. All were adsorbed in Tenax tubes and concentrations of carcinogenic or irritant volatile hydrocarbons measured by gas chromatography. The results were compared with cigarette smoke and urban city air control samples. The analyzing laboratory was blinded to sample origin. A total of 10 patients consented to intraoperative gas sampling in which only one method of energized dissection was used. Six carcinogenic or irritant hydrocarbons (benzene, ethylbenzene, styrene, toluene, heptene, and methylpropene) were identified in one or more samples. With the exception of styrene (P = 0.016), a nonsignificant trend toward lower hydrocarbon concentrations was observed with ultrasonic scalpel use. Ultrasonic scalpel plumes had significantly lower hydrocarbon concentrations than cigarette smoke, with the exception of methylpropene (P = 0.332). No significant difference was observed with city air. Electrocautery samples contained significantly lower hydrocarbon concentrations than cigarette smoke, with the exception of toluene (P = 0.117) and methyl propene (P = 0.914). Except for toluene (P = 0.028), city air showed no significant difference. Both electrocautery and ultrasonic dissection are associated with significantly lower concentrations of the most commonly detected carcinogenic and irritant hydrocarbons than cigarette smoke. A nonsignificant trend toward lower hydrocarbon concentrations was seen with ultrasonic scalpel dissection compared with diathermy. The contamination levels in city air were largely comparable with those seen after ultrasonic scalpel use. Although hydrocarbon concentrations are low, cumulative exposures may increase health risks. Where concerns arise, ultrasonic scalpel dissection may be preferable.

Occurrence of Pre- and Post-Harvest Mycotoxins and Other Secondary Metabolites in Danish Maize Silage

PubMed Central

Storm, Ida M. L. Drejer; Rasmussen, Rie Romme; Rasmussen, Peter Have

2014-01-01

Maize silage is a widely used feed product for cattle worldwide, which may be contaminated with mycotoxins, pre- and post-harvest. This concerns both farmers and consumers. To assess the exposure of Danish cattle to mycotoxins from maize silage, 99 samples of whole-crop maize (ensiled and un-ensiled) were analyzed for their contents of 27 mycotoxins and other secondary fungal metabolites by liquid chromatography-tandem mass spectrometry. The method specifically targets the majority of common pre- and post-harvest fungi associated with maize silage in Denmark. Sixty-one samples contained one or more of the 27 analytes in detectable concentrations. The most common mycotoxins were zearalenone, enniatin B nivalenol and andrastin A, found in 34%, 28%, 16% and 15% of the samples, respectively. None of the samples contained mycotoxins above the EU recommended maximum concentrations for Fusarium toxins in cereal-based roughage. Thus, the present study does not indicate that Danish maize silage in general is a cause of acute single mycotoxin intoxications in cattle. However, 31 of the samples contained multiple analytes; two samples as much as seven different fungal metabolites. Feed rations with maize silage may therefore contain complex mixtures of fungal secondary metabolites with unknown biological activity. This emphasizes the need for a thorough examination of the effects of chronic exposure and possible synergistic effects. PMID:25089350

Method for preconcentrating a sample for subsequent analysis

DOEpatents

Zaromb, Solomon

1990-01-01

A system for analysis of trace concentration of contaminants in air includes a portable liquid chromatograph and a preconcentrator for the contaminants to be analyzed. The preconcentrator includes a sample bag having an inlet valve and an outlet valve for collecting an air sample. When the sample is collected the sample bag is connected in series with a sorbing apparatus in a recirculation loop. The sorbing apparatus has an inner gas-permeable container containing a sorbent material and an outer gas-impermeable container. The sample is circulated through the outer container and around the inner container for trapping and preconcentrating the contaminants in the sorbent material. The sorbent material may be a liquid having the same composition as the mobile phase of the chromatograph for direct injection thereinto. Alternatively, the sorbent material may be a porous, solid body, to which mobile phase liquid is added after preconcentration of the contaminants for dissolving the contaminants, the liquid solution then being withdrawn for injection into the chromatograph.

Reevalution of background iodine-129 concentrations in water from the Snake River Plain Aquifer, Idaho, 2003

USGS Publications Warehouse

Cecil, L. DeWayne; Hall, L. Flint; Green, Jaromy R.

2003-01-01

Background concentrations of iodine-129 (129I, half-life = 15.7 million years) resulting from natural production in the earth?s atmosphere, in situ production in the earth by spontaneous fission of uranium-238(238U), and fallout from nuclear weapons tests conducted in the 1950s and 1960s were reevaluated on the basis of 52 analyses of ground- and surface-water samples collected from the eastern Snake River Plain in southeastern Idaho. The background concentration estimated using the results of a subset of 30 ground-water samples analyzed in this reevaluation is 5.4 attocuries per liter (aCi/L; 1 aCi = 10-18 curies) and the 95-percent nonparametric confidence interval is 5.2 to 10.0 aCi/L. In a previous study, a background 129I concentration was estimated on the basis of analyses of water samples from 16 sites on or tributary to the eastern Snake River Plain. At the 99-percent confidence level, background concentrations of 129I in that study were less than or equal to 8.2 aCi/L. During 1993?94, 34 water samples from 32 additional sites were analyzed for 129I to better establish the background concentrations in surface and ground water from the eastern Snake River Plain that is presumed to be unaffected by wastedisposal practices at the Idaho National Engineering and Environmental Laboratory (INEEL). Surface water contained larger 129I concentrations than water from springs and wells contained. Because surface water is more likely to be affected by anthropogenic fallout and evapotranspiration, background 129I concentrations were estimated in the current research using the laboratory results of ground-water samples that were assumed to be unaffected by INEEL disposal practices.

Evaluation of lipid-containing semipermeable membrane devices for monitoring organochlorine contaminants in the Upper Mississippi river

USGS Publications Warehouse

Ellis, Geoffrey S.; Rostad, Colleen E.; Huckins, James N.; Schmitt, Christopher J.; MacCarthy, Patrick

1995-01-01

Organochlorine contaminants sequestered in lipid-containing semipermeable membrane devices (SPMDs) were compared to those found in tangential-flow ultrafilter permeates as part of a pilot study at 10 sites in the Upper Mississippi River system. Caged and feral fish from three primary sites were also analyzed for comparison. Concentrated organochlorine (OC) compounds were readily extracted from the SPMDs by dialysis into hexane, and samples were analyzed by gas chromatography-negative chemical ionization-mass spectrometry. Fish and water samples were processed by conventional methods. Reasonable agreement was found between analyte SPMD-derived water concentrations and measured values of ultrafilter permeates; however, concentrations of the same analytes in caged fish did not appear to be proportional to water concentrations derived from SPMDs and ultrafilter permeates. The greatest number of OC compounds was detected in SPMDs; fewer were detected in caged fish and feral fish.

Method for determining the concentration of atomic species in gases and solids

DOEpatents

Loge, Gary W.

1999-01-01

Method for determining the concentration of atomic species in gases and solids. Measurement of at least two emission intensities from a species in a plasma containing the species after a sufficient time period has elapsed after the generation of the plasma and during a second time period, permits an instantaneous temperature to be established within the sample. The concentration of the atomic species to be determined is then derived from the known emission intensity of a predetermined concentration of that species in the sample at the measured temperature, a quantity which is measured prior to the determination of the unknown concentration, and the actual measured emission from the unknown species, or by this latter emission and the emission intensity of a species having known concentration within the sample.

Mercury in fish and macroinvertebrates from New York's streams and rivers: A compendium of data sources

USGS Publications Warehouse

Riva-Murray, Karen; Burns, Douglas A.

2016-01-01

The U.S. Geological Survey has compiled a list of existing data sets, from selected sources, containing mercury (Hg) concentration data in fish and macroinvertebrate samples that were collected from flowing waters of New York State from 1970 through 2014. Data sets selected for inclusion in this report were limited to those that contain fish and (or) macroinvertebrate data that were collected across broad areas, cover relatively long time periods, and (or) were collected as part of a broader-scale (e.g. national) study or program. In addition, all data sets listed were collected, processed, and analyzed with documented methods, and contain critical sample information (e.g. fish species, fish size, Hg species) that is needed to analyze and interpret the reported Hg concentration data. Fourteen data sets, all from state or federal agencies, are listed in this report, along with selected descriptive information regarding each data source and data set contents. Together, these 14 data sets contain Hg and related data for more than 7,000 biological samples collected from more than 700 unique stream and river locations between 1970 and 2014.

A new perspective on metals and other contaminants in fluoridation chemicals*

PubMed Central

Mullenix, Phyllis J

2014-01-01

Background: Fluoride additives contain metal contaminants that must be diluted to meet drinking water regulations. However, each raw additive batch supplied to water facilities does not come labeled with concentrations per contaminant. This omission distorts exposure profiles and the risks associated with accidents and routine use. Objectives: This study provides an independent determination of the metal content of raw fluoride products. Methods: Metal concentrations were analyzed in three hydrofluorosilicic acid (HFS) and four sodium fluoride (NaF) samples using inductively coupled plasma-atomic emission spectrometry. Arsenic levels were confirmed using graphite furnace atomic absorption analysis. Results: Results show that metal content varies with batch, and all HFS samples contained arsenic (4.9–56.0 ppm) or arsenic in addition to lead (10.3 ppm). Two NaF samples contained barium (13.3–18.0 ppm) instead. All HFS (212–415 ppm) and NaF (3312–3630 ppm) additives contained a surprising amount of aluminum. Conclusions: Such contaminant content creates a regulatory blind spot that jeopardizes any safe use of fluoride additives. PMID:24999851

Assessment of in vitro oxalate degradation by Lactobacillus species cultured from veterinary probiotics.

PubMed

Cho, Jenny G; Gebhart, Connie J; Furrow, Eva; Lulich, Jody P

2015-09-01

To culture Lactobacillus spp from veterinary probiotics and measure their in vitro oxalate-degrading capacity. 2 commercial veterinary probiotics containing Lactobacillus spp. Lactobacillus spp were cultured anaerobically on selective deMan, Rogosa, Sharpe agar medium and subcultured for speciation by 16S rDNA gene sequencing. Isolates were inoculated into broth containing sodium oxalate (5 mg/L) and incubated anaerobically for 72 hours. An oxalate-degrading isolate of Lactobacillus acidophilus (American Type Culture Collection [ATCC] 53544) was the positive control sample; sterile broth containing a known quantity of sodium oxalate was the negative control sample. Oxalate concentrations were detected with ion chromatography. Oxalate degradation was assessed with Dunnett tests to detect differences in mean oxalate concentration for each isolate, compared with results for the negative control. Lactobacillus acidophilus, Lactobacillus plantarum, and Lactobacillus casei or Lactobacillus zeae (too closely related to differentiate) were isolated from probiotic 1, and L plantarum was isolated from probiotic 2. Sequencing of the 16S rDNA gene confirmed 100% homology to type species. Lactobacillus acidophilus (ATCC 53544) and L acidophilus from probiotic 1 significantly decreased oxalate concentrations by 85.3 and 161.9 mg/L, respectively. Lactobacillus plantarum from probiotics 1 and 2 significantly increased oxalate concentrations by 56.1 and 36.1 mg/L, respectively. Lactobacillus casei did not alter oxalate concentrations. Lactobacillus acidophilus isolates significantly reduced oxalate concentrations. In vivo studies are needed to determine whether probiotics containing L acidophilus decrease urine oxalate concentrations and reduce risk of urolith recurrence in dogs with a history of calcium oxalate urolithiasis.

Stability of polymyxin B sulfate diluted in 0.9% sodium chloride injection and stored at 4 or 25 degrees C.

PubMed

He, Jie; Figueroa, Deborah A; Lim, Tze-Peng; Chow, Diana S; Tam, Vincent H

2010-07-15

The stability of polymyxin B sulfate in infusion bags containing 0.9% sodium chloride injection stored at 4 and 25 degrees C was studied. Seven manufacturing batches of polymyxin B from different sources were tested. The products were reconstituted in sterile water for injection, diluted in infusion bags containing 0.9% sodium chloride injection, and stored at room temperature (25 degrees C) or under refrigeration (4 degrees C). Samples were withdrawn at the same time on days 0, 1, 2, 3, 5, and 7. A modified microbiological assay was used to determine the concentrations, as indicated by zones of inhibition, of polymyxin B. Bordetella bronchiseptica served as the reference organism. Stability was defined as retention of >90% of the initial concentration. The decomposition kinetics of polymyxin B in 0.9% sodium chloride injection were evaluated by plotting the polymyxin B concentration remaining versus time. On average, the samples retained over 90% of their initial concentration for up to two days at both storage temperatures. All samples retained over 90% of their initial concentration at 24 hours. The decomposition kinetics of polymyxin B in infusion bags containing 0.9% sodium chloride injection exhibited pseudo-first-order kinetics, with rate constants of 0.024-0.075 day(-1) at 25 degrees C and 0.022-0.043 day(-1) at 4 degrees C (p > 0.05). Polymyxin B was stable for at least one day when stored at 4 or 25 degrees C in infusion bags containing 0.9% sodium chloride injection. Stability did not differ significantly between the two storage temperatures.

Serum zinc concentrations: contamination from laboratory equipment.

PubMed

Ralstin, J O; Schneider, P J; Blackstone, L; Ruberg, R L

1979-01-01

The following experiment was designed because of high serum zinc reported in patients who were reciving total parenteral nutrition (TPN) concentrations. Blood samples were collected, divided into 3 containers: a clean glass control test tube, a vacuum collecting tube with a rubber stopper, and paraffin clot activator. It was found that compared to glass control tubes, vacuum collection with rubber stoppers contributed an average of 76 +/- 14 microgram/dl of zinc as contaminants. Moreover, tubes with a rubber stopper and clot activator contributed 198 +/- 42 microgram/dl of zinc as contaminants. It is concluded that care must be used to avoid trace element contaminants when plasma zinc concentrations are analyzed. Without proper methodology, including selection of the container in which the sample is taken, erroneous results will be reported.

Determination of uptake kinetics (sampling rates) by lipid-containing semipermeable membrane devices (SPMDs) for polycyclic aromatic hydrocarbons (PAHs) in water

USGS Publications Warehouse

Huckins, J.N.; Petty, J.D.; Orazio, C.E.; Lebo, J.A.; Clark, R.C.; Gibson, V.L.; Gala, W.R.; Echols, K.R.

1999-01-01

The use of lipid-containing semipermeable membrane devices (SPMDs) is becoming commonplace, but very little sampling rate data are available for the estimation of ambient contaminant concentrations from analyte levels in exposed SPMDs. We determined the aqueous sampling rates (R(s)s; expressed as effective volumes of water extracted daily) of the standard (commercially available design) 1-g triolein SPMD for 15 of the priority pollutant (PP) polycyclic aromatic hydrocarbons (PAHs) at multiple temperatures and concentrations. Under the experimental conditions of this study, recovery- corrected R(s) values for PP PAHs ranged from ???1.0 to 8.0 L/d. These values would be expected to be influenced by significant changes (relative to this study) in water temperature, degree of biofouling, and current velocity- turbulence. Included in this paper is a discussion of the effects of temperature and octanol-water partition coefficient (K(ow)); the impacts of biofouling and hydrodynamics are reported separately. Overall, SPMDs responded proportionally to aqueous PAH concentrations; i.e., SPMD R(s) values and SPMD-water concentration factors were independent of aqueous concentrations. Temperature effects (10, 18, and 26 ??C) on Rs values appeared to be complex but were relatively small.The use of lipid-containing semipermeable membrane devices (SPMDs) is becoming commonplace, but very little sampling rate data are available for the estimation of ambient contaminant concentrations from analyte levels in exposed SPMDs. We determined the aqueous sampling rates (Rss; expressed as effective volumes of water extracted daily) of the standard (commercially available design) 1-g triolein SPMD for 15 of the priority pollutant (PP) polycyclic aromatic hydrocarbons (PAHs) at multiple temperatures and concentrations. Under the experimental conditions of this study, recovery-corrected Rs values for PP PAHs ranged from ???1.0 to 8.0 L/d. These values would be expected to be influenced by significant changes (relative to this study) in water temperature, degree of biofouling, and current velocity-turbulence. Included in this paper is a discussion of the effects of temperature and octanol-water partition coefficient (KOW); the impacts of biofouling and hydrodynamics are reported separately. Overall, SPMDs responded proportionally to aqueous PAH concentrations; i.e., SPMD RS values and SPMD-water concentration factors were independent of aqueous concentrations. Temperature effects (10, 18, and 26??C) on RS values appeared to be complex but were relatively small.

Chemistry, toxicology, and persistence of particulates during and after the 2016 Fort McMurray Wildfires in Alberta, Canada

NASA Astrophysics Data System (ADS)

Kohl, L.; Chan, A. W. H.; Cooke, C. A.; Hustins, S.; Jackson, B.; Wang, S.; Jing, X.; Meng, M.

2017-12-01

The Horse River Fire in May 2016 forced the evacuation of 88,000 Fort McMurray residents, and led to the destruction of over 2000 houses. After re-entry to homes, there is significant concern about exposures to residual fire-derived contaminants in residential houses. Wildfire research, however, provides little guidance on how long ashes and pollutants persist in household dust after major fires. The FACET project studies the chemistry and toxicology of samples of urban and forest ashes and airborne particles collected during the fire, as well as over 500 house dust samples collected in July 2017 (14 months after the fire). Here we present results on the chemical composition of the urban and forest ash samples collected during the fire along with initial results from house dust samples. Wildfire ashes contained elevated concentrations of polycyclic aromatic hydrocarbons (PAH), heavy metals, and dioxin like compounds (DLC). Relative to EPA reference doses, As and Sb constitute the greatest non-carcinogenic health hazard, whereas PAHs Benzo(a)pyrene and Indeno(1,2,3-cd)pyrene are the most relevant carcinogens. Ashes from urban locations contained higher concentrations of heavy metals and DLC than samples collected from forested areas outside of the City of Fort McMurray. Urban samples furthermore had a greater potential for generating oxidative stress than rural samples, as determined by dithiothreitol (DTT) consumption assays. The oxidative potential was positively correlated to Al, Cu, As, and V concentrations. Airborne particulate matter samples from the smoke plume contained consistent concentrations of levoglucosan (99 ± 5 mg g-1), along with other tracers for biomass burning (free lignin monomers, retene). Together these results will serve as proxies for understanding the contribution and the persistence of fire-derived pollutants in house dust in Fort McMurray homes.

Stability of nitroglycerin in intravenous admixtures.

PubMed

Klamerus, K J; Ueda, C T; Newton, D W

1984-02-01

The stability of nitroglycerin in intravenous admixtures was studied. Admixtures containing nitroglycerin 400 micrograms/ml and each of seven injectable drugs in concentrations used clinically were prepared in triplicate in 5% dextrose and 0.9% sodium chloride injections. Admixtures were stored in glass bottles at room temperature for 24 hours in the upright position and then for 24 hours in the inverted position to ensure contact of the solution with the rubber stopper of the container. At 0, 24, and 48 hours, samples of each admixture were assayed by high-performance liquid chromatography for nitroglycerin concentration. The pH of one randomly chosen bottle of each admixture was measured at 0, 24, and 48 hours. A significant loss of nitroglycerin potency at 48 hours was observed only in admixtures containing phenytoin; in these solutions, a 9% decrease in initial nitroglycerin concentration was noted. Phenytoin crystallization was present in all phenytoin admixtures by 24 hours. Compared with initial values, no significant differences in the pH values of any admixture samples assayed at 24 and 48 hours were noted; however, admixtures containing phenytoin had the most alkaline pH values. Under the conditions studied, nitroglycerin concentrations remained above 90% of their initial values for 48 hours in all tested admixtures; however, phenytoin crystallization limits the stability of phenytoin admixtures.

Uranium concentration and distribution in six peridotite inclusions of probable mantle origin

NASA Technical Reports Server (NTRS)

Haines, E. L.; Zartman, R. E.

1973-01-01

Fission-track activation was used to investigate uranium concentration and distribution in peridotite inclusions in alkali basalt from six localities. Whole-rock uranium concentrations range from 24 to 82 ng/g. Most of the uranium is uniformly distributed in the major silicate phases - olivine, orthopyroxene, and clinopyroxene. Chromian spinels may be classified into two groups on the basis of their uranium content - those which have less than 10 ng/g and those which have 100 to 150 ng/g U. In one sample accessory hydrous phases, phlogopite and hornblende, contain 130 and 300 ng/g U, respectively. The contact between the inclusion and the host basalt is usually quite sharp. Glassy or microcrystalline veinlets found in some samples contain more than 1 microgram/g. Very little uranium is associated with microcrystals of apatite. These results agree with some earlier investigators, who have concluded that suboceanic peridotites contain too little uranium to account for normal oceanic heat flow by conduction alone.

EPA Contract Laboratory Program Statement of Work for Inorganic Superfund Methods Multi-Media, Multi-Concentration ISM02.3

EPA Pesticide Factsheets

This document contains analytical methods for the analysis of metals and cyanide in environmental samples. It also contains contractual requirements for laboratories participating in Superfund's Contract Laboratory Program.

EPA Contract Laboratory Program Statement of Work for Inorganic Superfund Methods Multi-Media, Multi-Concentration ISM02.4

EPA Pesticide Factsheets

This document contains analytical methods for the analysis of metals and cyanide in environmental samples. It also contains contractual requirements for laboratories participating in Superfund's Contract Laboratory Program.

Proteolysis of milk fat globule membrane proteins during in vitro gastric digestion of milk.

PubMed

Ye, A; Cui, J; Singh, H

2011-06-01

The influence of gastric proteolysis on the physicochemical characteristics of milk fat globules and the proteins of the milk fat globule membrane (MFGM) in raw milk and cream was examined in vitro in simulated gastric fluid (SGF) containing various pepsin concentrations at pH 1.6 for up to 2h. Apparent flocculation of the milk fat globules occurred in raw milk samples incubated in SGF containing pepsin, but no coalescence was observed in either raw milk samples or cream samples. The changes in the particle size of the fat globules as a result of the flocculation were dependent on the pepsin concentration. Correspondingly, the physical characteristics of the fat globules and the composition of the MFGM proteins in raw milk changed during incubation in SGF containing pepsin. The major MFGM proteins were hydrolyzed at different rates by the pepsin in the SGF; butyrophilin was more resistant than xanthine oxidase, PAS 6, or PAS 7. Peptides with various molecular weights, which altered with the time of incubation and the pepsin concentration, were present at the surfaces of the fat globules. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Population exposure to trace elements in the Kilembe copper mine area, Western Uganda: A pilot study.

PubMed

Mwesigye, Abraham R; Young, Scott D; Bailey, Elizabeth H; Tumwebaze, Susan B

2016-12-15

The mining and processing of copper in Kilembe, Western Uganda, from 1956 to 1982 left over 15 Mt. of tailings containing cupriferous and cobaltiferous pyrite dumped within a mountain river valley. This pilot study was conducted to assess the nature and extent of risk to local populations from metal contamination arising from those mining activities. We determined trace element concentrations in mine tailings, soils, locally cultivated foods, house dust, drinking water and human biomarkers (toenails) using ICP-MS analysis of acid digested samples. The results showed that tailings, containing higher concentrations of Co, Cu, Ni and As compared with world average crust values had eroded and contaminated local soils. Pollution load indices revealed that 51% of agricultural soils sampled were contaminated with trace elements. Local water supplies were contaminated, with Co concentrations that exceeded Wisconsin (US) thresholds in 25% of domestic water supplies and 40% of Nyamwamba river water samples. Zinc exceeded WHO/FAO thresholds of 99.4mgkg -1 in 36% of Amaranthus vegetable samples, Cu exceeded EC thresholds of 20mgkg -1 in 19% of Amaranthus while Pb exceeded WHO thresholds of 0.3mgkg -1 in 47% of Amaranthus vegetables. In bananas, 20% of samples contained Pb concentrations that exceeded the WHO/FAO recommended threshold of 0.3mgkg -1 . However, risk assessment of local foods and water, based on hazard quotients (HQ values) revealed no potential health effects. The high external contamination of volunteers' toenails with some elements (even after a washing process) calls into question their use as a biomarker for metal exposure in human populations where feet are frequently exposed to soil dust. Any mitigation of Kilembe mine impacts should be aimed at remediation of agricultural soils, regulating the discharge of underground contaminated water but also containment of tailing erosion. Copyright © 2016 Elsevier B.V. All rights reserved.

Water quality of hydrologic bench marks; an indicator of water quality in the natural environment

USGS Publications Warehouse

Biesecker, James E.; Leifeste, Donald K.

1974-01-01

Water-quality data, collected at 57 hydrologic bench-mark stations in 37 States, allow the definition of water quality in the 'natural' environment and the comparison of 'natural' water quality with water quality of major streams draining similar water-resources regions. Results indicate that water quality in the 'natural' environment is generally very good. Streams draining hydrologic bench-mark basins generally contain low concentrations of dissolved constituents. Water collected at the hydrologic bench-mark stations was analyzed for the following minor metals: arsenic, barium, cadmium, hexavalent chromium, cobalt, copper, lead, mercury, selenium, silver, and zinc. Of 642 analyses, about 65 percent of the observed concentrations were zero. Only three samples contained metals in excess of U.S. Public Health Service recommended drinking-water standards--two selenium concentrations and one cadmium concentration. A total of 213 samples were analyzed for 11 pesticidal compounds. Widespread but very low-level occurrence of pesticide residues in the 'natural' environment was found--about 30 percent of all samples contained low-level concentrations of pesticidal compounds. The DDT family of pesticides occurred most commonly, accounting for 75 percent of the detected occurrences. The highest observed concentration of DDT was 0.06 microgram per litre, well below the recommended maximum permissible in drinking water. Nitrate concentrations in the 'natural' environment generally varied from 0.2 to 0.5 milligram per litre. The average concentration of nitrate in many major streams is as much as 10 times greater. The relationship between dissolved-solids concentration and discharge per unit area in the 'natural' environment for the various physical divisions in the United States has been shown to be an applicable tool for approximating 'natural' water quality. The relationship between dissolved-solids concentration and discharge per unit area is applicable in all the physical divisions of the United States, except the Central Lowland province of the Interior Plains, the Great Plains province of the Interior Plains, and the Basin and Ridge province of the Intermontane Plateaus. The relationship between dissolved-solids concentration and discharge per unit area is least variable in the New England province and Blue Ridge province of the Appalachian Highlands. The dissolved-solids concentration versus discharge per unit area in the Central Lowland province of the Interior Plains is highly variable. A sample collected from the hydrologic bench-mark station at Bear Den Creek near Mandaree, N. Dak., contained 3,420 milligrams per litre dissolved solids. This high concentration in the 'natural' environment indicates that natural processes can be principal agents in modifying the environment and can cause degradation. Average annual runoff and rock type can be used as predictive tools to determine the maximum dissolved-solids concentration expected in the 'natural' environment.

Demonstration of a longitudinal concentration gradient along scala tympani by sequential sampling of perilymph from the cochlear apex.

PubMed

Mynatt, Robert; Hale, Shane A; Gill, Ruth M; Plontke, Stefan K; Salt, Alec N

2006-06-01

Local applications of drugs to the inner ear are increasingly being used to treat patients' inner ear disorders. Knowledge of the pharmacokinetics of drugs in the inner ear fluids is essential for a scientific basis for such treatments. When auditory function is of primary interest, the drug's kinetics in scala tympani (ST) must be established. Measurement of drug levels in ST is technically difficult because of the known contamination of perilymph samples taken from the basal cochlear turn with cerebrospinal fluid (CSF). Recently, we reported a technique in which perilymph was sampled from the cochlear apex to minimize the influence of CSF contamination (J. Neurosci. Methods, doi: 10.1016/j.jneumeth.2005.10.008 ). This technique has now been extended by taking smaller fluid samples sequentially from the cochlear apex, which can be used to quantify drug gradients along ST. The sampling and analysis methods were evaluated using an ionic marker, trimethylphenylammonium (TMPA), that was applied to the round window membrane. After loading perilymph with TMPA, 10 1-muL samples were taken from the cochlear apex. The TMPA content of the samples was consistent with the first sample containing perilymph from apical regions and the fourth or fifth sample containing perilymph from the basal turn. TMPA concentration decreased in subsequent samples, as they increasingly contained CSF that had passed through ST. Sample concentration curves were interpreted quantitatively by simulation of the experiment with a finite element model and by an automated curve-fitting method by which the apical-basal gradient was estimated. The study demonstrates that sequential apical sampling provides drug gradient data for ST perilymph while avoiding the major distortions of sample composition associated with basal turn sampling. The method can be used for any substance for which a sensitive assay is available and is therefore of high relevance for the development of preclinical and clinical strategies for local drug delivery to the inner ear.

Demonstration of a Longitudinal Concentration Gradient Along Scala Tympani by Sequential Sampling of Perilymph from the Cochlear Apex

PubMed Central

Mynatt, Robert; Hale, Shane A.; Gill, Ruth M.; Plontke, Stefan K.

2006-01-01

ABSTRACT Local applications of drugs to the inner ear are increasingly being used to treat patients' inner ear disorders. Knowledge of the pharmacokinetics of drugs in the inner ear fluids is essential for a scientific basis for such treatments. When auditory function is of primary interest, the drug's kinetics in scala tympani (ST) must be established. Measurement of drug levels in ST is technically difficult because of the known contamination of perilymph samples taken from the basal cochlear turn with cerebrospinal fluid (CSF). Recently, we reported a technique in which perilymph was sampled from the cochlear apex to minimize the influence of CSF contamination (J. Neurosci. Methods, doi: http://10.1016/j.jneumeth.2005.10.008). This technique has now been extended by taking smaller fluid samples sequentially from the cochlear apex, which can be used to quantify drug gradients along ST. The sampling and analysis methods were evaluated using an ionic marker, trimethylphenylammonium (TMPA), that was applied to the round window membrane. After loading perilymph with TMPA, 10 1-μL samples were taken from the cochlear apex. The TMPA content of the samples was consistent with the first sample containing perilymph from apical regions and the fourth or fifth sample containing perilymph from the basal turn. TMPA concentration decreased in subsequent samples, as they increasingly contained CSF that had passed through ST. Sample concentration curves were interpreted quantitatively by simulation of the experiment with a finite element model and by an automated curve-fitting method by which the apical–basal gradient was estimated. The study demonstrates that sequential apical sampling provides drug gradient data for ST perilymph while avoiding the major distortions of sample composition associated with basal turn sampling. The method can be used for any substance for which a sensitive assay is available and is therefore of high relevance for the development of preclinical and clinical strategies for local drug delivery to the inner ear. PMID:16718612

Brassicaceae tissues as inhibitors of nitrification in soil.

PubMed

Brown, Paul D; Morra, Matthew J

2009-09-09

Brassicaceae crops often produce an unexplained increase in plant-available soil N possibly related to bioactive compounds produced from glucosinolates present in the tissues. Our objective was to determine if glucosinolate-containing tissues inhibit nitrification, thereby potentially explaining this observation. Ammonium, NO(2)(-), and NO(3)(-) N were measured in soils amended with Brassicaceae ( Isatis tinctoria L., Brassica napus L., Brassica juncea L., and Sinapis alba L.) tissues containing different glucosinolate types and concentrations or Kentucky bluegrass ( Poa pratensis L.) residues with equivalent C/N ratios as the Brassicaceae samples. There was greater accumulation of NH(4)(+) N in soils amended with tissues containing high glucosinolate concentrations as compared to soils amended with tissues containing no or low glucosinolate concentrations. Nitrite N was detected only in soils amended with Brassicaceae tissues having the highest glucosinolate concentrations. The positive correlation of both NH(4)(+) and NO(2)(-) N accumulation with the glucosinolate concentration indicates the participation of glucosinolate hydrolysis products in nitrification inhibition.

Relation of a seafood diet to mercury, selenium, arsenic, and polychlorinated biphenyl and other organochlorine concentrations in human milk.

PubMed

Grandjean, P; Weihe, P; Needham, L L; Burse, V W; Patterson, D G; Sampson, E J; Jørgensen, P J; Vahter, M

1995-10-01

Human transition milk was sampled from 88 mothers at the Faroe Islands, where the seafood diet includes pilot whale meat and blubber. Milk mercury concentrations (median, 2.45 micrograms/liter) were significantly associated with mercury concentrations in cord blood and with the frequency of pilot whale dinners during pregnancy. Milk selenium concentrations (mean, 19.1 micrograms/liter) correlated significantly with concentrations in cord blood but not with seafood consumption. Arsenic concentrations were very low. Twenty-four of the milk samples were separated into four pools based on fish intake and milk mercury concentrations. The polychlorinated biphenyl (PCB) concentrations (1.8-3.5 micrograms/g lipid) were high and mainly due to congener numbers 153, 180, and 138. One pool contained a congener 77 concentration of 1380 ppt, which is the highest ever reported in a human specimen for a coplanar PCB. The highest PCB concentrations were seen in the pools from women who had eaten frequent whale dinners and whose milk contained high mercury concentrations. The concentrations of chlorinated dibenzo-p-dioxins and furans were not similarly elevated. Given the advantages associated with breast-feeding, advice to nursing mothers in this population should take into regard the possible risks associated with long-term exposure to milk contaminants.

Helium in soil gases of the Roosevelt Hot Springs Known Geothermal Resource Ares, Beaver County, Utah

USGS Publications Warehouse

Hinkle, M.E.; Denton, E.H.; Bigelow, R.C.; Turner, R.L.

1978-01-01

Soil samples were collected in two parallel traverses across the Dome fault zone of the Roosevelt Hot Springs Known Geothermal Resource Area. The samples were sealed in air-tight aluminum cans, and the soil gas was allowed to equilibrate with the atmospheric air in the cans. Gas from the cans was analyzed by mass spectrometry. Samples collected over faults contained anomalously high concentrations of helium. Samples collected close to a geothermal well 884 m deep contained more helium than samples collected near another geothermal well 1370 m deep.

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).

Elemental analysis of urinary calculi by laser induced plasma spectroscopy.

PubMed

Fang, Xiao; Ahmad, S Rafi; Mayo, Mike; Iqbal, Syed

2005-12-01

Laser induced plasma spectroscopy (LIPS) has been applied to analyse and identify elemental constituents of urinary calculi. Measurements on seven different urinary stone samples were conducted and the concentrations of some key elemental species were estimated. The elements detected with the present system were: Calcium, Magnesium, Sodium, Samarium, Potassium and Lead. Absolute concentrations of the species were derived from pre-calibration of the system for each element. Their concentrations were found to be widely different in different samples. It was observed that the samples containing a significant amount of lead have large proportion of calcium. It has been established that LIPS would allow real time clinic measurements of elemental contents and the concentrations in the biomaterials without sample preparation. The technique has the potential for routine clinic applications in urological disorder diagnosis.

Determination of selected anions in water by ion chromatography

USGS Publications Warehouse

Fishman, Marvin J.; Pyen, Grace

1979-01-01

Ion chromatography is a rapid, sensitive, precise, and accurate method for the determination of major anions in rain water and surface waters. Simultaneous analyses of a single sample for bromide, chloride, fluoride, nitrate, nitrite, orthophosphate, and sulfate require approximately 20 minutes to obtain a chromatogram.Minimum detection limits range from 0.01 milligrams per liter for fluoride to 0.20 milligrams per liter for chloride and sulfate. Percent relative standard deviations were less than nine percent for all anions except nitrite in Standard Reference Water Samples. Only one reference sample contained nitrite and its concentration was near the minimum level of detection. Similar precision was found for chloride, nitrate, and sulfate at concentrations less than 5 milligrams per liter in rainfall samples. Precision for fluoride ranged from 12 to 22 percent, but is attributed to the low concentrations in these samples. The other anions were not detected.To determine accuracy of results, several samples were spiked with known concentrations of fluoride, chloride, nitrate, and sulfate; recoveries ranged from 96 to 103 percent. Known amounts of bromide and phosphate were added, separately, to several other waters, which contained bromide or phosphate. Recovery of added bromide and phosphate ranged from approximately 95 to 104 percent. No recovery data were obtained for nitrite.Chloride, nitrate, nitrite, orthophosphate, and sulfate, in several samples, were also determined independently by automated colorimetric procedures. An automated ion-selective electrode method was used to determine fluoride. Results are in agreement with results obtained by ion chromatography.

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.

Determination of phosphate concentration and pH in artificial tear drops.

PubMed

de Frutos-Lezaun, M; Martínez-Soroa, I; Ostra Beldarrain, M; Egia Zurutuza, A; Irastorza Larburu, M B; Fernandez Iriarte, A; Bachiller Cacho, M P

2016-08-01

To determine phosphate concentration and pH in artificial tear eye drops commercially available in Spain. A total of 71 examples of artificial tear preparations were identified in a search of Vademecum 2014 and the Spanish Medicines Agency website. In the 24 artificial tear products containing phosphates, quantification of these was performed by ultraviolet molecular absorption spectrophotometry, and the determination of pH was performed using scan image analysis algorithms of pH strips. Of the 71 artificial tears tested, 24 contained phosphate among their excipients in the data sheet, three of which had a concentration level below detection limit (<0.1mM). The mean phosphate concentration was 17.91±23.87mM. The artificial tear sample containing a higher concentration was Colircusi Humectante (87.1mM). Lubricants based on hypromellose showed the highest phosphate concentration (41.59±32.1mM), showing statistically significant differences compared to povidone (P=.0196) and hyaluronate (P=.0067). Statistically significant differences were found between products containing preservatives (32.39±20.91mM), and preservative free ones (8.49±11.98mM) (P=.0498). However, no difference was found between multidose (20.21±26.91mM) and unidose (9.31±14.39mM) samples, or between brand name (15.44±23.3mM) and generic eye drops (20.81mM). The mean pH was 6.93±0.26 (6.2-7.22). No statistical correlation was detected between phosphate concentration and pH (Spearman's Rho -0.1089 and P=.6125). A total of 24 (33.8%) of the 71 artificial tears contained phosphate. We believe identifying the phosphate concentration of artificial tears is useful information in order to avoid complications in high-risk patients. Copyright © 2016. Published by Elsevier España, S.L.U.

Characterization of cyanophyte biomass in a Bureau of Reclamation reservoir

USGS Publications Warehouse

Simon, Nancy S.; Ali, Ahmad Abdul; Samperton, Kyle Michael; Korson, Charles S.; Fischer, Kris; Hughes, Michael L.

2013-01-01

The purpose of this study was to characterize the cyanophyte Aphanizomenon flos-aquae (AFA) from Upper Klamath Lake, Oregon, (UKL) and, based on this description, explore uses for AFA, which would have commercial value. AFA collected from UKL in 2010 from eight sites during a period of approximately 2 weeks were similar in composition spatially and temporally. 31P nuclear magnetic resonance analysis of the samples indicated that the AFA samples contained a broad range of phosphorus-containing compounds. The largest variation in organic phosphorus compounds was found in a sample collected from Howard Bay compared with samples collected the sites at Pelican Marina, North Buck Island, Eagle Ridge, Eagle Ridge South, Shoalwater Bay, and Agency Lake South. 31P Nuclear Magnetic Resonance data indicated that the average ratio of inorganic phosphorus (orthophosphate) to organic phosphorus in the AFA samples was approximately 60:40 in extraction solutions of either water or a more rigorous solution of sodium hydroxide plus ethylenediaminetetraacetic acid. This indicates that when AFA cells senesce, die and lyse, cell contents added to the water column contain a broad spectrum of phosphorus-containing compounds approximately 50 percent of which are organic phosphorus compounds. The organic phosphorus content of AFA is directly and significantly related to the total carbon content of AFA. Total concentrations of the elements Al, Ca, Fe, Mg, Ti and Zn were similar in all samples with the exception of elevated iron in the July 27, 2010, sample from Pelican Marina. Iron concentration in the July 27, 2010, Pelican Marina sample was elevated; the concentration of iron in the August 9, 2010, sample from Pelican Marina was indistinguishable from iron in the other AFA samples that were collected. The carbon to nitrogen ratio in all AFA samples that were analyzed was 5.4 plus or minus 0.04 as compared with the Redfield ratio of carbon to nitrogen ratio of 6.6, which could be attributed to the large concentrations of nitrogen (protein) in AFA or to optimal growth rate. In UKL there is a concern that microcystin, the toxin produced by microcystis, might be present in what appears to be predominantly AFA in the lake water. Experiments preformed as part of this study identified a process that reduces the toxicity of microcystin when it is present in water slurry containing AFA. The process combines (1) the inhibition of the α, ß-unsaturated carbonyl in microcystin with (2) the breakdown of proteins in AFA using the protease activity of plant enzymes. Protease enzymes can break peptide bonds in microcystin, which results in destruction of the cyclic structure of the microcystin polypeptide. Laboratory conditions used in this study resulted in the inactivation of approximately 60 percent of the activity of microcystin.

Surveillance of Total Mercury and Methylmercury Concentrations in Retail Fish.

PubMed

Watanabe, Takahiro; Hayashi, Tomoko; Matsuda, Rieko; Akiyama, Hiroshi; Teshima, Reiko

2017-01-01

Most fish samples contain methylmercury, that the concentrations very greatly according to the fish species. To avoid the adverse health effects of methylmercury while retaining the benefits provided by fish consumption, it is important to select suitable fish species and to control the amount of the fish intake. We surveyed the concentrations of total mercury and methylmercury in 210 retail fish samples classified into 19 fish species by using validated analytical methods. The results of this survey were as follows. The total mercury and methylmercury concentrations were higher than 1 mg/kg in some samples of swordfish and bluefin tuna, which are large predatory fish species. In bluefin tuna and yellowtail, total mercury and methylmercury concentrations in farm-raised fish were lower than those in natural fish. There was a positive correlation between total mercury concentration and methylmercury concentration. Our results indicate that a cut-off value of 0.3 mg/kg total mercury in the screening of fish samples would increase the effectiveness of inspection.

A portable molecular-sieve-based CO{sub 2} sampling system for radiocarbon measurements

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

Palonen, V., E-mail: vesa.palonen@helsinki.fi

We have developed a field-capable sampling system for the collection of CO{sub 2} samples for radiocarbon-concentration measurements. Most target systems in environmental research are limited in volume and CO{sub 2} concentration, making conventional flask sampling hard or impossible for radiocarbon studies. The present system captures the CO{sub 2} selectively to cartridges containing 13X molecular sieve material. The sampling does not introduce significant under-pressures or significant losses of moisture to the target system, making it suitable for most environmental targets. The system also incorporates a significantly larger sieve container for the removal of CO{sub 2} from chambers prior to the CO{submore » 2} build-up phase and sampling. In addition, both the CO{sub 2} and H{sub 2}O content of the sample gas are measured continuously. This enables in situ estimation of the amount of collected CO{sub 2} and the determination of CO{sub 2} flux to a chamber. The portable sampling system is described in detail and tests for the reliability of the method are presented.« less

Fluoride content in table salt distributed in Mexico City, Mexico.

PubMed

Hernández-Guerrero, Juan Carlos; de la Fuente-Hernández, Javier; Jiménez-Farfán, Maria Dolores; Ledesma-Montes, Constantino; Castañeda-Castaneira, Enrique; Molina-Frechero, Nelly; Jacinto-Alemán, Luís Fernando; Juárez-Lopez, Lilia Adriana; Moreno-Altamirano, Alejandra

2008-01-01

The aim of this study was to analyze table salt available in Mexico City's market to identify the fluoride concentrations and to compare these with the Mexican regulations. We analyzed 44 different brands of table salt. All samples were purchased at random in different stores, supermarkets, and groceries from Mexico City's metropolitan area and analyzed in triplicate in three different laboratories (nine determinations per sample) with an Orion 720 A potentiometer and an Orion 9609 BN ion-specific electrode. Fluoride concentration in the samples varied from 0 ppm to 485 ppm. It was found that fluoride concentration varied widely among the analyzed brands. Also, we found that fluoride concentration in 92 percent of the analyzed samples did not match with that printed on the label. Only 6.8 percent of the analyzed samples contained fluoride concentrations that meet Mexican and WHO regulations. The broad variation in the analyzed samples suggests that Mexican Public Health authorities must implement more stringent regulation guidelines and procedures for controlling the distribution of salt and its fluoride concentration for human consumption.

Stability and availability of cyclosporine in 5% dextrose injection or 0.9% sodium chloride injection.

PubMed

Ptachcinski, R J; Logue, L W; Burckart, G J; Venkataramanan, R

1986-01-01

The stability of cyclosporine in commonly used i.v. solutions and the percentage of the drug delivered via polyvinyl chloride administration tubing were studied. Cyclosporine injection was prepared according to the manufacturer's instructions and diluted with 5% dextrose injection (D5W) or with 0.9% sodium chloride injection (NS). Admixtures containing cyclosporine 2 mg/mL were prepared in polyvinyl chloride minibags (five for each solution) and in glass containers (three for each solution). The sample obtained at time zero from a glass container protected from light was the control. Additional samples were prepared in minibags and run through 70-inch polyvinyl chloride administration sets. An HPLC assay for cyclosporine was used. Exposure to room light did not significantly affect cyclosporine concentrations. More than 90% of the initial drug concentration remained after 24 hours under all storage conditions, but less than 95% remained after 6 hours in samples diluted with NS and stored in plastic. At times up to 60 minutes, cyclosporine concentrations were significantly different in solutions infused from the minibags through polyvinyl chloride tubing from those in control solutions. Under these conditions, cyclosporine is stable in D5W in glass containers or polyvinyl chloride minibags for 24 hours and in NS for 6 hours (polyvinyl chloride) to 12 hours (glass). However, because of the potential for leaching of plasticizers, cyclosporine admixtures should be stored in glass or used within six hours if stored in polyvinyl chloride minibags. Approximately 10% of the initial drug concentration is lost to 70-inch length polyvinyl chloride infusion tubing.

Characterization Results for the January 2017 H-Tank Farm 2H Evaporator Overhead Sample

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

Truong, T.; Nicholson, J.

2017-04-11

This report contains the radioanalytical results of the 2H evaporator overhead sample received at SRNL on January 19, 2017. Specifically, concentrations of 137Cs, 90Sr, and 129I are reported and compared to the corresponding Waste Acceptance Criteria (WAC) limits of the Effluent Treatment Project (ETP) Waste Water Collection Tank (WWCT) (rev. 6). All of the radionuclide concentrations in the sample were found to be in compliance with the ETP WAC limits.

Characterization Results for the March 2016 H-Tank Farm 2H Evaporator Overhead Samples

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

Nicholson, J. C.

2016-05-09

This report contains the radioanalytical results of the 2H evaporator overhead sample received at SRNL on March 16, 2016. Specifically, concentrations of 137Cs, 90Sr, and 129I are reported and compared to the corresponding Waste Acceptance Criteria (WAC) limits of the Effluent Treatment Project (ETP) Waste Water Collection Tank (WWCT) (rev. 6). All of the radionuclide concentrations in the sample were found to be in compliance with the ETP WAC limits.

Plasma/muscle ratios of sulfadimethoxine residues in channel catfish (Ictalurus punctatus).

PubMed

Walker, C C; Thune, R L; Barker, S A

1995-08-01

Channel catfish (n = 84) maintained at a water temperature of 27 degrees C were used in a feeding study to determine the plasma to muscle concentration ratios of sulfadimethoxine (SDM) and 4-N-acetylsulfadimethoxine residues. Sulfadimethoxine medicated feed was provided free choice at 42 mg SDM/kg body weight once daily for 5 days and the plasma and muscle concentrations of SDM were determined at selected withdrawal times (6, 12, 24, 48, 72, and 96 hours) following the last dose. Considerable variation in total SDM tissue concentration among fish within a sampling period was observed. For fish (n = 12) at six hours post-dose, total SDM concentrations ranged from 1.4-24.8 micrograms/mL and 0.6-12.6 micrograms/g, with mean total SDM concentrations of 9.1 micrograms/mL and 5.3 micrograms/g for plasma and muscle, respectively. However, a mean plasma:muscle concentration ratio of 1.8:1 +/- 0.3:1 was obtained over all concentrations and sampling periods. The plasma:muscle 95% t distribution interval for individual fish was 1.2:1 to 2.4:1. A correlation coefficient of 0.967 was obtained for the relationship between plasma and muscle total SDM concentration among individual fish (n = 25). Results of this study indicate that plasma total SDM concentration may be used to identify samples containing violative SDM muscle residue. No fish contained total SDM muscle residues greater than the FDA tolerance (0.1 microgram/g) by 48 hours following the final dose.

Preservation of samples for dissolved mercury

USGS Publications Warehouse

Hamlin, S.N.

1989-01-01

Water samples for dissolved mercury requires special treatment because of the high chemical mobility and volatility of this element. Widespread use of mercury and its compounds has provided many avenues for contamination of water. Two laboratory tests were done to determine the relative permeabilities of glass and plastic sample bottles to mercury vapor. Plastic containers were confirmed to be quite permeable to airborne mercury, glass containers were virtually impermeable. Methods of preservation include the use of various combinations of acids, oxidants, and complexing agents. The combination of nitric acid and potassium dichromate successfully preserved mercury in a large variety of concentrations and dissolved forms. Because this acid-oxidant preservative acts as a sink for airborne mercury and plastic containers are permeable to mercury vapor, glass bottles are preferred for sample collection. To maintain a healthy work environment and minimize the potential for contamination of water samples, mercury and its compounds are isolated from the atmosphere while in storage. Concurrently, a program to monitor environmental levels of mercury vapor in areas of potential contamination is needed to define the extent of mercury contamination and to assess the effectiveness of mercury clean-up procedures.Water samples for dissolved mercury require special treatment because of the high chemical mobility and volatility of this element. Widespread use of mercury and its compounds has provided many avenues for contamination of water. Two laboratory tests were done to determine the relative permeabilities of glass and plastic sample bottles to mercury vapor. Plastic containers were confirmed to be quite permeable to airborne mercury, glass containers were virtually impermeable. Methods of preservation include the use of various combinations of acids, oxidants, and complexing agents. The combination of nitric acid and potassium dichromate successfully preserved mercury in a large variety of concentrations and dissolved forms.

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.

Results of the radiological survey at the Town of Tonawanda Landfill, Tonawanda, New York (TNY001)

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

Rodriguez, R.E.; Murray, M.E.; Uziel, M.S.

At the request of the US Department of Energy (DOE), a team from Oak Ridge National Laboratory conducted a radiological survey at the Town of Tonawanda Landfill, Tonawanda, New York. The survey was performed in September 1991. The purpose of the survey was to determine if radioactive materials from work performed under government contract at the Linde Air Products Division of Union Carbide Corporation, Tonawanda, New York, had been deposited in the landfill. The survey included a surface gamma scan and the collection of soil samples for radionuclide analyses. Results of the survey suggest that material originating at the Lindemore » plant may have been deposited in the landfill. Soil samples S54 and B12 contained technologically enhanced levels of [sup 238]U not unlike the product formerly produced by the Linde plant. In contrast, samples B4A, B5A and B7B, containing elevated concentrations of [sup 226]Ra and [sup 230]Th with much lower concentrations of [sup 238]U, were similar to the residue or byproduct of the refinery operation conducted at the Linde plant. In 24 instances, soil samples from the Town of Tonawanda Landfill exceeded DOE guideline values for [sup 238]U, [sup 226]Ra, and/or [sup 230]Th in surface or subsurface soil. Nine of these samples contained radionuclide concentrations more than 30 times the guideline value.« less

Improving the accuracy of sediment-associated constituent concentrations in whole storm water samples by wet-sieving

USGS Publications Warehouse

Selbig, W.R.; Bannerman, R.; Bowman, G.

2007-01-01

Sand-sized particles (>63 ??m) in whole storm water samples collected from urban runoff have the potential to produce data with substantial bias and/or poor precision both during sample splitting and laboratory analysis. New techniques were evaluated in an effort to overcome some of the limitations associated with sample splitting and analyzing whole storm water samples containing sand-sized particles. Wet-sieving separates sand-sized particles from a whole storm water sample. Once separated, both the sieved solids and the remaining aqueous (water suspension of particles less than 63 ??m) samples were analyzed for total recoverable metals using a modification of USEPA Method 200.7. The modified version digests the entire sample, rather than an aliquot, of the sample. Using a total recoverable acid digestion on the entire contents of the sieved solid and aqueous samples improved the accuracy of the derived sediment-associated constituent concentrations. Concentration values of sieved solid and aqueous samples can later be summed to determine an event mean concentration. ?? ASA, CSSA, SSSA.

Concentrations of selected constituents in surface-water and streambed-sediment samples collected from streams in and near an area of oil and natural-gas development, south-central Texas, 2011-13

USGS Publications Warehouse

Opsahl, Stephen P.; Crow, Cassi L.

2014-01-01

During collection of streambed-sediment samples, additional samples from a subset of three sites (the SAR Elmendorf, SAR 72, and SAR McFaddin sites) were processed by using a 63-µm sieve on one aliquot and a 2-mm sieve on a second aliquot for PAH and n-alkane analyses. The purpose of analyzing PAHs and n-alkanes on a sample containing sand, silt, and clay versus a sample containing only silt and clay was to provide data that could be used to determine if these organic constituents had a greater affinity for silt- and clay-sized particles relative to sand-sized particles. The greater concentrations of PAHs in the <63-μm size-fraction samples at all three of these sites are consistent with a greater percentage of binding sites associated with fine-grained (<63 μm) sediment versus coarse-grained (<2 mm) sediment. The larger difference in total PAHs between the <2-mm and <63-μm size-fraction samples at the SAR Elmendorf site might be related to the large percentage of sand in the <2-mm size-fraction sample which was absent in the <63-μm size-fraction sample. In contrast, the <2-mm size-fraction sample collected from the SAR McFaddin site contained very little sand and was similar in particle-size composition to the <63-μm size-fraction sample.

Assessment of workplace air concentrations of formaldehyde during and before working hours in medical facilities.

PubMed

Higashikubo, Ichiro; Miyauchi, Hiroyuki; Yoshida, Satoru; Tanaka, Shinsuke; Matsuoka, Mitsunori; Arito, Heihachiro; Araki, Akihiro; Shimizu, Hidesuke; Sakurai, Haruhiko

2017-04-07

Workplace air concentrations of formaldehyde (FA) in medical facilities where FA and FA-treated organs were stored and handled were measured before and during working hours and assessed by the official method specified by Work Environment Measurement Law. Sixty-percent of the total facilities examined were judged as inappropriately controlled work environment. The concentrations of FA before working hours by spot sampling were found to exceed 0.1 ppm in some facilities, and tended to increase with increasing volume of containers storing FA and FA-treated materials. Regression analysis revealed that logarithmic concentrations of FA during working hours by the Law-specified analytical method were highly correlated with those before working hours by spot sampling, suggesting the importance for appropriate storing methods of FA and FA-treated materials. The concentrations of FA during working hours are considered to be lowered by effective ventilation of FA-contaminated workplace air and appropriate storage of FA and FA-treated materials in plastic containers in the medical facilities. In particular, such improvement by a local exhaust ventilation system and tightly-sealed containment of FA-treated material were urgently needed for the dissecting room where FA-treated cadavers were prepared and handled for a gross anatomy course in a medical school.

National Water Quality Laboratory, 1995 services catalog

USGS Publications Warehouse

Timme, P.J.

1995-01-01

This Services Catalog contains information about field supplies and analytical services available from the National Water Quality Laboratory in Denver, Colo., and field supplies available from the Quality Water Service Unit in Ocala, Fla., to members of the U.S. Geological Survey. To assist personnel in the selection of analytical services, this catalog lists sample volume, required containers, applicable concentration range, detection level, precision of analysis, and preservation requirements for samples.

Purgeable organic compounds in ground water at the Idaho National Engineering Laboratory, Idaho; 1988 and 1989

USGS Publications Warehouse

Mann, L.J.

1990-01-01

Groundwater samples from 38 wells at the Idaho National Engineering Laboratory were analyzed for 36 purgeable organic compounds in 1988-89. Thirty-six of the wells obtain water from the Snake River Plain aquifer and were equipped with dedicated or portable pumps. Water samples from one well that obtains water from the aquifer and one that obtains water from a perched groundwater zone were collected using a thief sampler. Analyses of water from 22 wells indicated the aquifer locally contained detectable concentrations of at least 1 of 19 purgeable organic compounds, mainly carbon tetrachloride, 1,1,1-trichloroethane, and trichloroethylene. Except for five wells, the maximum concentration of a specific compound in groundwater was 6.4 microgram/L or less; concentrations of most compounds were less than 0.2 microgram/L. Water from four wells at and near the Test Area North contained from 44 to 29, 000 micrograms/L of trichloroethylene. Water from a well that obtains water from a discontinuous perched groundwater zone at the Radioactive Waste Management Complex contained 1,400 micrograms/L of carbon tetrachloride, 940 micrograms/L of chloroform, 250 micrograms/L of 1,1,1- trichloroethane, and 1,100 micrograms/L trichloroethylene. Selected purgeable organic compounds, such as total xylene and methylene chloride, were detected in some groundwater samples and some blank samples consisting of boiled deionized water. Their presence in the blank samples suggest the compounds could have been inadvertently introduced into the groundwater sampled during or subsequent to collection. (USGS)

Aflatoxin and ochratoxin A content of spices in Hungary.

PubMed

Fazekas, B; Tar, A; Kovács, M

2005-09-01

In October and November 2004, 91 spice samples (70 ground red pepper, six black pepper, five white pepper, five spice mix and five chilli samples), the majority of which originated from commercial outlets, were analysed for aflatoxins B1, B2, G1 and G2 (AFB1, AFB2, AFG1, AFG2) and ochratoxin A (OTA) content by high-performance liquid chromatography (HPLC) after immunoaffinity column clean-up. Eighteen of the 70 ground red pepper samples contained AFB1, seven of them in a concentration exceeding the 'maximum level' of 5 microg kg(-1) (range 6.1-15.7 microg kg(-1)). Of the other spices assayed, the AFB1 contamination of one chilli sample exceeded 5 microg kg(-1) (8.1 microg kg(-1)). Thirty-two of the 70 ground red pepper samples contained OTA, eight of them in a concentration exceeding the 10 microg kg(-1) 'maximum level' (range 10.6-66.2 microg kg(-1)). One chilli sample was contaminated with OTA at 2.1 microg kg(-1). The AFB1 and OTA contamination of ground red pepper exceeding the 'maximum level' (5 and 10 microg kg(-1), respectively) was obviously the consequence of mixing imported ground red pepper batches heavily contaminated with AFB1 and OTA with red pepper produced in Hungary. This case calls attention to the importance of consistently screening imported batches of ground red pepper for aflatoxin and ochratoxin A content and strictly prohibiting the use of batches containing mycotoxin concentrations exceeding the maximum permitted level.

Analysis of betaine and choline contents of aleurone, bran, and flour fractions of wheat (Triticum aestivum L.) Using (1)H nuclear magnetic resonance (NMR) spectroscopy.

PubMed

Graham, Stewart F; Hollis, James H; Migaud, Marie; Browne, Roy A

2009-03-11

In conventional milling, the aleurone layer is combined with the bran fraction. Studies indicate that the bran fraction of wheat contains the majority of the phytonutrients betaine and choline, with relatively minor concentrations in the refined flour. This present study suggests that the wheat aleurone layer ( Triticum aestivum L. cv. Tiger) contains the greatest concentration of both betaine and choline (1553.44 and 209.80 mg/100 g of sample, respectively). The bran fraction contained 866.94 and 101.95 mg/100 g of sample of betaine and choline, respectively, while the flour fraction contained 23.30 mg/100 g of sample (betaine) and 28.0 mg/100 g of sample (choline). The betaine content for the bran was lower, and the choline content was higher compared to previous studies, although it is known that there is large variation in betaine and choline contents between wheat cultivars. The ratio of betaine/choline in the aleurone fraction was approximately 7:1; in the bran, the ratio was approximately 8:1; and in the flour fraction, the ratio was approximately 1:1. The study further emphasizes the superior phytonutrient composition of the aleurone layer.

Interpretation of urinary concentrations of pseudoephedrine and its metabolite cathine in relation to doping control.

PubMed

Deventer, K; Van Eenoo, P; Baele, G; Pozo, O J; Van Thuyne, W; Delbeke, F T

2009-05-01

Until the end of 2003 a urinary concentration of pseudoephedrine exceeding 25 microg/mL was regarded as a doping violation by the World Anti-Doping Agency. Since its removal from the prohibited list in 2004 the number of urine samples in which pseudoephedrine was detected in our laboratory increased substantially. Analysis of 116 in-competition samples containing pseudoephedrine in 2007 and 2008, revealed that 66% of these samples had a concentration of pseudoephedrine above 25 microg/mL. This corresponded to 1.4% of all tested in competition samples in that period. In the period 2001-2003 only 0.18% of all analysed in competition samples contained more than 25 microg/mL. Statistical comparison of the two periods showed that after the removal of pseudoephedrine from the list its use increased significantly. Of the individual sports compared between the two periods, only cycling is shown to yield a significant increase.Analysis of excretion urine samples after administration of a therapeutic daily dose (240 mg pseudoephedrine) in one administration showed that the threshold of 25 microg/mL can be exceeded. The same samples were also analysed for cathine, which has currently a threshold of 5 microg/mL on the prohibited list. The maximum urinary concentration of cathine also exceeded the threshold for some volunteers. Comparison of the measured cathine and pseudoephedrine concentrations only indicated a poor correlation between them. Hence, cathine is not a good indicator to control pseudopehedrine intake. To control the (ab)use of ephedrines in sports it is recommended that WADA reintroduce a threshold for pseudoephedrine. Copyright 2009 John Wiley & Sons, Ltd.

Stability of low levels of perchlorate in drinking water and natural water samples

USGS Publications Warehouse

Stetson, S.J.; Wanty, R.B.; Helsel, D.R.; Kalkhoff, S.J.; Macalady, D.L.

2006-01-01

Perchlorate ion (ClO4-) is an environmental contaminant of growing concern due to its potential human health effects, impact on aquatic and land animals, and widespread occurrence throughout the United States. The determination of perchlorate cannot normally be carried out in the field. As such, water samples for perchlorate analysis are often shipped to a central laboratory, where they may be stored for a significant period before analysis. The stability of perchlorate ion in various types of commonly encountered water samples has not been generally examined-the effect of such storage is thus not known. In the present study, the long-term stability of perchlorate ion in deionized water, tap water, ground water, and surface water was examined. Sample sets containing approximately 1000, 100, 1.0, and 0.5 ??g l-1 perchlorate ion in deionized water and also in local tap water were formulated. These samples were analyzed by ion chromatography for perchlorate ion concentration against freshly prepared standards every 24 h for the first 7 days, biweekly for the next 4 weeks, and periodically after that for a total of 400 or 610 days for the two lowest concentrations and a total of 428 or 638 days for the high concentrations. Ground and surface water samples containing perchlorate were collected, held and analyzed for perchlorate concentration periodically over at least 360 days. All samples except for the surface water samples were found to be stable for the duration of the study, allowing for holding times of at least 300 days for ground water samples and at least 90 days for surface water samples. ?? 2006 Elsevier B.V. All rights reserved.

Differentiation of Cannabis subspecies by THCA synthase gene analysis using RFLP.

PubMed

Cirovic, Natasa; Kecmanovic, Miljana; Keckarevic, Dusan; Keckarevic Markovic, Milica

2017-10-01

Cannabis sativa subspecies, known as industrial hemp (C. sativa sativa) and marijuana (C. sativa indica) show no evident morphological distinctions, but they contain different levels of psychoactive Δ-9-tetrahidrocanabinol (THC), with considerably higher concentration in marijuana than in hemp. C. sativa subspecies differ in sequence of tetrahydrocannabinolic acid (THCA) synthase gene, responsible for THC production, and only one active copy of the gene, distinctive for marijuana, is capable of producing THC in concentration more then 0,3% in dried plants, usually punishable by the law. Twenty different samples of marijuana that contain THC in concentration more then 0,3% and three varieties of industrial hemp were analyzed for presence of an active copy of THCA synthase gene using in-house developed restriction fragment length polymorphism (RFLP) method All twenty samples of marijuana were positive for the active copy of THCA synthase gene, 16 of them heterozygous. All three varieties of industrial hemp were homozygous for inactive copy. An algorithm for the fast and accurate forensic analysis of samples suspected to be marijuana was constructed, answering the question if an analyzed sample is capable of producing THC in concentrations higher than 0.3%. Copyright © 2017 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) in e-waste plastic in Nigeria.

PubMed

Sindiku, O; Babayemi, J O; Tysklind, M; Osibanjo, O; Weber, R; Watson, A; Schlummer, M; Lundstedt, S

2015-10-01

Plastics from cathode ray tube (CRT) casings were sampled in Nigeria and analysed for their polybrominated dibenzo-p-dioxin and dibenzofuran (PBDD/F) content. PBDD/Fs, consisting mainly of PBDFs, were detected in BFR containing plastic with a median (mean) concentration of 18,000 ng/g (41,000 ng/g). The PBDD/Fs levels were highest in samples containing PBDEs, but the levels of PBDFs were two orders of magnitude higher than the levels reported in the technical PBDE mixtures and where frequently exceeding 1000 μg/g of PBDE content. These higher levels are likely to arise from additional transformation of PBDEs during production, use, recycling, or storage, but the processes responsible were not identified in this study. PBDD/Fs in CRT casings containing1,2-bistribromophenoxyethane (TBPE) were dominated by tetrabrominated dibenzo-p-dioxin (TBDDs) with concentrations around 10 μg/g of the TBPE content. The PBDD/Fs in CRT casings containing tetrabromobisphenol A (TBBPA) were found at concentrations around 0.1 μg/g of TBBPA levels. Casings treated with TBPE or TBBPA often contained PBDEs (and PBDF) as impurities-probably originating from recycled e-waste plastics. It was estimated that the 237,000 t of CRT casings stockpiled in Nigeria contain between 2 and 8 t of PBDD/Fs. The total PBDD/F contamination in polymers arising from total historic PBDE production/use is estimated in the order of 1000 t. TEQ values of CRT samples frequently exceeded the Basel Convention's provisional low POPs content of 15 ng TEQ/g. Due to the significant risks to health associated with PBDD/Fs, more detailed studies on the exposure routes from PBDD/Fs in stockpiles are needed.

Occurrence and distribution of selected contaminants in public drinking-water supplies in the surficial aquifer in Delaware

USGS Publications Warehouse

Ferrari, Matthew J.

2001-01-01

Water samples were collected from August through November 2000 from 30 randomly selected public drinking-water supply wells screened in the unconfined aquifer in Delaware, and analyzed to assess the occurrence and distribution of selected pesticide compounds, volatile organic compounds, major inorganic ions, and nutrients. Water from a subset of 10 wells was sampled and analyzed for radium and radon. The average age of ground water entering the well screens in all the wells was determined to be generally less than 20 years. Low concentrations of pesticide compounds and volatile organic compounds were detected throughout the State of Delaware, with several compounds often detected in each water sample. Pesticide and metabolite (pesticide degradation products) concentrations were generally less than 1 microgram per liter, and were detected in sam-ples from 27 of 30 wells. Of the 45 pesticides and 13 metabolites analyzed, 19 compounds (13 pesticides and 6 metabolites) were detected in at least 1 of the 30 samples. Desethylatrazine, alachlor ethane sulfonic acid, metolachlor ethane sulfonic acid, metolachlor, and atrazine were the most frequently detected pesticide compounds, and were present in at least half the samples. None of the pesticide detections was above the U.S. Environmental Protection Agency's Primary Maximum Contaminant Levels or Health Advisories. Volatile organic compounds also were present at low concentrations (generally less than 1 microgram per liter) in samples from all 30 wells. Of the 85 volatile organic com-pounds analyzed, 34 compounds were detected in at least 1 of the 30 samples. Chloroform, tetrachloroethene, and methyl tert-butyl ether were the most frequently detected volatile organic compounds, and were found in at least half the samples. None of the volatile organic compound detections was above U.S. Environmental Protection Agency's Primary Maximum Contaminant Levels or Health Advisories. A few samples contained compounds with concentrations above the U.S. Environmental Protection Agency's Primary Maximum Contaminant Levels or Secondary Maximum Contaminant Levels for inorganic compounds and radionuclides. One sample out of 30 contained a concentration of nitrite plus nitrate above the U.S. Environmental Protection Agency's Primary Maximum Contaminant Level of 10 milligrams per liter as nitrogen. Iron and manganese concentrations above the U.S. Environmental Protection Agency's Secondary Maximum Contaminant Levels were found in 7 of 30 ground-water samples, most of them from Sussex County. In the 10 wells sampled for radionuclides, only one sample had detectable levels of radium-224 and -226, and another sample contained detectable levels of radium-228; both of these samples also had detectable gross-alpha and gross-beta activities. None of these activities were above the U.S. Environ-mental Protection Agency's Primary Maximum Contaminant Levels or Secondary Maximum Contaminant Levels. Radon was detected in all 10 samples, but was above the current U.S. Environmental Protection Agency's proposed Primary Maximum Contaminant Level of 300 picocuries per liter in only one sample.

Stability of Alprostadil in 0.9% Sodium Chloride Stored in Polyvinyl Chloride Containers.

PubMed

McCluskey, Susan V; Kirkham, Kylian; Munson, Jessica M

2017-01-01

The stability of alprostadil diluted in 0.9% sodium chloride stored in polyvinyl chloride (VIAFLEX) containers at refrigerated temperature, protected from light, is reported. Five solutions of alprostadil 11 mcg/mL were prepared in 250 mL 0.9% sodium chloride polyvinyl chloride (PL146) containers. The final concentration of alcohol was 2%. Samples were stored under refrigeration (2°C to 8°C) with protection from light. Two containers were submitted for potency testing and analyzed in duplicate with the stability-indicating high-performance liquid chromatography assay at specific time points over 14 days. Three containers were submitted for pH and visual testing at specific time points over 14 days. Stability was defined as retention of 90% to 110% of initial alprostadil concentration, with maintenance of the original clear, colorless, and visually particulate-free solution. Study results reported retention of 90% to 110% initial alprostadil concentration at all time points through day 10. One sample exceeded 110% potency at day 14. pH values did not change appreciably over the 14 days. There were no color changes or particle formation detected in the solutions over the study period. This study concluded that during refrigerated, light-protected storage in polyvinyl chloride (VIAFLEX) containers, a commercial alcohol-containing alprostadil formulation diluted to 11 mcg/mL with 0.9% sodium chloride 250 mL was stable for 10 days. Copyright© by International Journal of Pharmaceutical Compounding, Inc.

Combined analysis of job and task benzene air exposures among workers at four US refinery operations

PubMed Central

Shin, Jennifer (Mi); Unice, Ken M; Gaffney, Shannon H; Kreider, Marisa L; Gelatt, Richard H; Panko, Julie M

2016-01-01

Workplace air samples analyzed for benzene at four US refineries from 1976 to 2007 were pooled into a single dataset to characterize similarities and differences between job titles, tasks and refineries, and to provide a robust dataset for exposure reconstruction. Approximately 12,000 non-task (>180 min) personal samples associated with 50 job titles and 4000 task (<180 min) samples characterizing 24 tasks were evaluated. Personal air sample data from four individual refineries were pooled based on a number of factors including (1) the consistent sampling approach used by refinery industrial hygienists over time, (2) the use of similar exposure controls, (3) the comparability of benzene content of process streams and end products, (4) the ability to assign uniform job titles and task codes across all four refineries, and (5) our analysis of variance (ANOVA) of the distribution of benzene air concentrations for select jobs/tasks across all four refineries. The jobs and tasks most frequently sampled included those with highest potential contact with refinery product streams containing benzene, which reflected the targeted sampling approach utilized by the facility industrial hygienists. Task and non-task data were analyzed to identify and account for significant differences within job-area, task-job, and task-area categories. This analysis demonstrated that in general, areas with benzene containing process streams were associated with greater benzene air concentrations compared to areas with process streams containing little to no benzene. For several job titles and tasks analyzed, there was a statistically significant decrease in benzene air concentration after 1990. This study provides a job and task-focused analysis of occupational exposure to benzene during refinery operations, and it should be useful for reconstructing refinery workers’ exposures to benzene over the past 30 years. PMID:26862134

Combined analysis of job and task benzene air exposures among workers at four US refinery operations.

PubMed

Burns, Amanda; Shin, Jennifer Mi; Unice, Ken M; Gaffney, Shannon H; Kreider, Marisa L; Gelatt, Richard H; Panko, Julie M

2017-03-01

Workplace air samples analyzed for benzene at four US refineries from 1976 to 2007 were pooled into a single dataset to characterize similarities and differences between job titles, tasks and refineries, and to provide a robust dataset for exposure reconstruction. Approximately 12,000 non-task (>180 min) personal samples associated with 50 job titles and 4000 task (<180 min) samples characterizing 24 tasks were evaluated. Personal air sample data from four individual refineries were pooled based on a number of factors including (1) the consistent sampling approach used by refinery industrial hygienists over time, (2) the use of similar exposure controls, (3) the comparability of benzene content of process streams and end products, (4) the ability to assign uniform job titles and task codes across all four refineries, and (5) our analysis of variance (ANOVA) of the distribution of benzene air concentrations for select jobs/tasks across all four refineries. The jobs and tasks most frequently sampled included those with highest potential contact with refinery product streams containing benzene, which reflected the targeted sampling approach utilized by the facility industrial hygienists. Task and non-task data were analyzed to identify and account for significant differences within job-area, task-job, and task-area categories. This analysis demonstrated that in general, areas with benzene containing process streams were associated with greater benzene air concentrations compared to areas with process streams containing little to no benzene. For several job titles and tasks analyzed, there was a statistically significant decrease in benzene air concentration after 1990. This study provides a job and task-focused analysis of occupational exposure to benzene during refinery operations, and it should be useful for reconstructing refinery workers' exposures to benzene over the past 30 years.

Optimization of the cydex blue assay: A one-step colorimetric protein assay using cyclodextrins and compatible with detergents and reducers

PubMed Central

2018-01-01

Sodium dodecyl sulfate electrophoresis (SDS) is a protein separation technique widely used, for example, prior to immunoblotting. Samples are usually prepared in a buffer containing both high concentrations of reducers and high concentrations of SDS. This conjunction renders the samples incompatible with common protein assays. By chelating the SDS, cyclodextrins make the use of simple, dye-based colorimetric assays possible. In this paper, we describe the optimization of the assay, focussing on the cyclodextrin/SDS ratio and the use of commercial assay reagents. The adaptation of the assay to a microplate format and using other detergent-containing conventional extraction buffers is also described. PMID:29641569

Evaluation of the furosine and homoarginine methods for determining reactive lysine in rumen-undegraded protein.

PubMed

Boucher, S E; Pedersen, C; Stein, H H; Schwab, C G

2009-08-01

Three samples of soybean meal (SBM), 3 samples of expeller SBM (SoyPlus, West Central Cooperative, Ralston, IA), 5 samples of distillers dried grains with solubles (DDGS), and 5 samples of fish meal were used to evaluate the furosine and homoarginine procedures to estimate reactive Lys in the rumen-undegraded protein fraction (RUP-Lys). One sample each of SBM, expeller SBM, and DDGS were subjected to additional heat treatment in the lab to ensure there was a wide range in reactive RUP-Lys content among the samples. Furosine is a secondary product of the initial stages of the Maillard reaction and can be used to calculate blocked Lys. Homoarginine is formed via the reaction of reactive Lys with O-methylisourea and can be used to calculate the concentration of reactive Lys. In previous experiments, each sample was ruminally incubated in situ for 16 h, and standardized RUP-Lys digestibility of the samples was determined in cecectomized roosters. All rumen-undegraded residue (RUR) samples were analyzed for furosine and Lys; however, only 9 of the 16 samples contained furosine, and only the 4 unheated DDGS samples contained appreciable amounts of furosine. Blocked RUP-Lys was calculated from the furosine and Lys concentrations of the RUR. Both the intact feed and RUR samples were evaluated using the homoarginine method. All samples were incubated with an O-methylisourea/BaOH solution for 72 h and analyzed for Lys and homoarginine concentrations. Reactive Lys concentrations of the intact feeds and RUR were calculated. Results of the experiment indicate that blocked RUP-Lys determined via the furosine method was negatively correlated with standardized RUP-Lys digestibility, and reactive RUP-Lys determined via the guanidination method was positively correlated with standardized RUP-Lys digestibility. Reactive Lys concentrations of the intact samples were also highly correlated with RUP-Lys digestibility. In conclusion, the furosine assay is useful in predicting RUP-Lys digestibility of DDGS samples, and the guanidination procedure can be used to predict RUP-Lys digestibility of SBM, expeller SBM, DDGS, and fish meal samples.

Exogenous thyrotoxicosis in dogs attributable to consumption of all-meat commercial dog food or treats containing excessive thyroid hormone: 14 cases (2008-2013).

PubMed

Broome, Michael R; Peterson, Mark E; Kemppainen, Robert J; Parker, Valerie J; Richter, Keith P

2015-01-01

To describe findings in dogs with exogenous thyrotoxicosis attributable to consumption of commercially available dog foods or treats containing high concentrations of thyroid hormone. Retrospective and prospective case series. 14 dogs. Medical records were retrospectively searched to identify dogs with exogenous thyrotoxicosis attributable to dietary intake. One case was found, and subsequent cases were identified prospectively. Serum thyroid hormone concentrations were evaluated before and after feeding meat-based products suspected to contain excessive thyroid hormone was discontinued. Scintigraphy was performed to evaluate thyroid tissue in 13 of 14 dogs before and 1 of 13 dogs after discontinuation of suspect foods or treats. Seven samples of 5 commercially available products fed to 6 affected dogs were analyzed for thyroxine concentration; results were subjectively compared with findings for 10 other commercial foods and 6 beef muscle or liver samples. Total serum thyroxine concentrations were high (median, 8.8 μg/dL; range, 4.65 to 17.4 μg/dL) in all dogs at initial evaluation; scintigraphy revealed subjectively decreased thyroid gland radionuclide in 13 of 13 dogs examined. At ≥ 4 weeks after feeding of suspect food or treats was discontinued, total thyroxine concentrations were within the reference range for all dogs and signs associated with thyrotoxicosis, if present, had resolved. Analysis of tested food or treat samples revealed a median thyroxine concentration for suspect products of 1.52 μg of thyroxine/g, whereas that of unrelated commercial foods was 0.38 μg of thyroxine/g. Results indicated that thyrotoxicosis can occur secondary to consumption of meat-based products presumably contaminated by thyroid tissue, and can be reversed by identification and elimination of suspect products from the diet.

Acoustically levitated droplets: a contactless sampling method for fluorescence studies.

PubMed

Leiterer, Jork; Grabolle, Markus; Rurack, Knut; Resch-Genger, Ute; Ziegler, Jan; Nann, Thomas; Panne, Ulrich

2008-01-01

Acoustic levitation is used as a new tool to study concentration-dependent processes in fluorescence spectroscopy. With this technique, small amounts of liquid and solid samples can be measured without the need for sample supports or containers, which often limits signal acquisition and can even alter sample properties due to interactions with the support material. We demonstrate that, because of the small sample volume, fluorescence measurements at high concentrations of an organic dye are possible without the limitation of inner-filter effects, which hamper such experiments in conventional, cuvette-based measurements. Furthermore, we show that acoustic levitation of liquid samples provides an experimentally simple way to study distance-dependent fluorescence modulations in semiconductor nanocrystals. The evaporation of the solvent during levitation leads to a continuous increase of solute concentration and can easily be monitored by laser-induced fluorescence.

Concentrations and distribution of manmade organic compounds in the Lake Tahoe Basin, Nevada and California, 1997-99

USGS Publications Warehouse

Lico, Michael S.; Pennington, Nyle

1999-01-01

The U.S. Geological Survey, in cooperation with the Tahoe Regional Planning Agency and the Lahontan Regional Water-Quality Control Board, sampled Lake Tahoe, major tributary streams to Lake Tahoe, and several other lakes in the Lake Tahoe Basin for manmade organic compounds during 1997-99. Gasoline components were found in all samples collected from Lake Tahoe during the summer boating season. Methyl tert-butyl ether (MTBE), benzene, toluene, ethylbenzene, and xylenes (BTEX) were the commonly detected compounds in these samples. Most samples from tributary streams and lakes with no motorized boating had no detectable concentrations of gasoline components. Motorized boating activity appears to be directly linked in space and time to the occurrence of these gasoline components. Other sources of gasoline components to Lake Tahoe, such as the atmosphere, surface runoff, and subsurface flow, are minor compared to the input by motorized boating. Water sampled from Lake Tahoe during mid-winter, when motorized boating activity is low, had no MTBE and only one sample had any detectable BTEX compounds. Soluble pesticides rarely were detected in water samples from the Lake Tahoe Basin. The only detectable concentrations of these compounds were in samples from Blackwood and Taylor Creeks collected during spring runoff. Concentrations found in these samples were low, in the 1 to 4 nanograms per liter range. Organochlorine compounds were detected in samples collected from semipermeable membrane devices (SPMD's) collected from Lake Tahoe, tributary streams, and Upper Angora Lake. In Lake Tahoe, SPMD samples collected offshore from urbanized areas contained the largest number and highest concentrations of organochlorine compounds. The most commonly detected organochlorine compounds were cis- and trans-chlordane, p, p'-DDE, and hexachlorobenzene. In tributary streams, SPMD samples collected during spring runoff generally had higher combined concentrations of organochlorine compounds than those collected during baseflow conditions. Upper Angora Lake had the fewest number of organochlorine compounds detected of all lake samples. Dioxins and furans were not detected in SPMD samples from two sites in Lake Tahoe or from two tributary streams. The number of polycyclic aromatic hydrocarbon (PAH) compounds and their combined concentrations generally were higher in samples from Lake Tahoe than those from tributary streams. Areas of high-motorized boating activity at Lake Tahoe had the largest number and highest concentrations of PAH's. PAH compounds were detected in samples from SPMD's in four of six tributary streams during spring runoff, all tributary streams during baseflow conditions, and at all lake sites. The most commonly detected PAH's in tributary streams during spring runoff were phenanthrene, fluoranthene, pyrene, and chrysene, and during baseflow conditions were phenanthrene, 1-methylphenanthrene, diethylnaphthalene, and pyrene. Upper Truckee River, which has an urban area in its drainage basin, had the largest number and highest combined concentration of PAH's of all stream samples. Bottom-sediment from Lake Tahoe had detectable concentrations of p-cresol, a phenol, in all but one sample. A sample collected near Chambers Lodge contained phenol at an estimated concentration of 4 micrograms per kilogram (?g/kg). Bottom-sediment samples from tributary streams had no detectable concentrations of organochlorine or PAH compounds. Several compounds were detected in bottom sediment from Upper Angora Lake at high concentrations. These compounds and their concentrations were p, p'-DDD (10 ?g/kg), p, p'-DDE (7.4 ?g/kg), 2,6-dimethylnaphthalene (estimated at 190 ?g/kg), pentachlorophenol (3,000 ?g/kg), and p-cresol (4,400 ?g/kg).

Analysis of Tank 38H (HTF-38-17-52, -53) and Tank 43H (HTF-43-17-54, -55) Samples for Support of the Enrichment Control and Corrosion Control Programs

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

Hay, M.; Coleman, C.; Diprete, D.

SRNL analyzed samples from Tank 38H and Tank 43H to support ECP and CCP. The total uranium in the Tank 38H surface sample was 41.3 mg/L while the sub-surface sample was 43.5 mg/L. The Tank 43H samples contained total uranium concentrations of 28.5 mg/L in the surface sample and 28.1 mg/L in the sub-surface sample. The U-235 percentage ranged from 0.62% to 0.63% for the Tank 38H samples and Tank 43H samples. The total uranium and percent U-235 results in the table appear slightly lower than recent Tank 38H and Tank 43H uranium measurements. The plutonium results in the tablemore » show a large difference between the surface and sub-surface sample concentrations for Tank 38H. The Tank 43H plutonium results closely match the range of values measured on previous samples. The Cs-137 results for the Tank 38H surface and sub-surface samples show similar concentrations slightly higher than the concentrations measured in recent samples. The Cs-137 results for the two Tank 43H samples also show similar concentrations within the range of values measured on previous samples. The four samples show silicon concentrations somewhat lower than the previous samples with values ranging from 124 to 168 mg/L.« less

Beneficial effects of polyethylene packages containing micrometer-sized silver particles on the quality and shelf life of dried barberry (Berberis vulgaris).

PubMed

Motlagh, N Valipoor; Mosavian, M T Hamed; Mortazavi, S A; Tamizi, A

2012-01-01

In this research, the effects of low-density polyethylene (LDPE) packages containing micrometer-sized silver particles (LDPE-Ag) on microbial and sensory factors of dried barberry were investigated in comparison with the pure LDPE packages. LDPE-Ag packages with 1% and 2% concentrations of silver particles statistically caused a decrease in the microbial growth of barberry, especially in the case of mold and total bacteria count, compared with the pure LDPE packages. The taste, aroma, appearance, and total acceptance were evaluated by trained panelists using the 9-point hedonic scale. This test showed improvement of all these factors in the samples related to packages containing 1% and 2% concentrations of silver particles in comparison with other samples. Low-density polyethylene package containing micrometer-sized silver particles had beneficial effects on the sensory and microbial quality of barberry when compared with normal packing material. © 2011 Institute of Food Technologists®

Toxic metals in imported fruits and vegetables marketed in Kuwait

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

Husain, A.; Baroon, Z.; Al-Khalafawi, M.

1995-12-31

The concentration of lead, cadmium, and mercury in 134 samples of imported fruits and vegetables marketed in Kuwait were determined using an atomic absorption spectrophotometer with a graphite furnace and the cold vapor technique. Results obtained showed that the concentration of these metal ions in most cases did not exceed the maximum permissible concentration of metals in fresh fruits and vegetables as restricted by some countries. Only a few samples of fruits and vegetables contained levels of mercury, cadmium, and lead which exceeded these maximum permissible levels.

Specific wavelength colorimeter. [for measuring given solute concentration in test sample

NASA Technical Reports Server (NTRS)

Brawner, C. C.; Mcdavid, L. S.; Walsh, J. M. (Inventor)

1974-01-01

A self contained, specific wavelength, single beam colorimeter is described for direct spectrophotometric measurement of the concentration of a given solute in a test sample. An electrical circuit employing a photoconductive cell converts the optical output into a linear, directly readable meter output. The colorimeter is simple to operate and is adapted for use in zero gravity conditions. In a specific application, the colorimeter is designed to analyze the concentration of iodine in potable water carried aboard a space vehicle such as the 4B stage of Skylab.

Using a portable ion mobility spectrometer to screen dietary supplements for sibutramine.

PubMed

Dunn, Jamie D; Gryniewicz-Ruzicka, Connie M; Kauffman, John F; Westenberger, Benjamin J; Buhse, Lucinda F

2011-02-20

In response to recent incidents of undeclared sibutramine, an appetite suppressant found in dietary supplements, we developed a method to detect sibutramine using hand-held ion mobility spectrometers with an analysis time of 15 s. Ion mobility spectrometry is a high-throughput and sensitive technique that has been used for illicit drug, explosive, volatile organic compound and chemical warfare detection. We evaluated a hand-held ion mobility spectrometer as a tool for the analysis of supplement extracts containing sibutramine. The overall instrumental limit of detection of five portable ion mobility spectrometers was 2 ng of sibutramine HCl. When sample extractions containing 30 ng/μl or greater of sibutramine were analyzed, saturation of the ionization chamber of the spectrometer occurred and the instrument required more than three cleaning cycles to remove the drug. Hence, supplement samples suspected of containing sibutramine should be prepared at concentrations of 2-20 ng/μl. To obtain this target concentration range for products containing unknown amounts of sibutramine, we provided a simple sample preparation procedure, allowing the U.S. Food and Drug Administration or other agencies to screen products using the portable ion mobility spectrometer. Published by Elsevier B.V.

USE OF FENTON'S REAGENT AS A DISINFECTANT

EPA Science Inventory

Combined sewage samples obtained from a wastewater treatment facility were disinfected by the Fenton's Reagent of several different compositions. The pre-settled samples contained both suspended solids (SS) and dissolved organic carbon (DOC) at concentrations of 28 and 290 mg/L,...

Examination of lead concentrations in new decorative enamel paints in four countries with different histories of activity in lead paint regulation

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

Clark, C. Scott, E-mail: clarkcs@ucmail.uc.edu; International POPS Elimination Network; Kumar, Abhay

Paints with high lead concentrations (ppm) continue to be sold around the world in many developing countries and those with economies in transition representing a major preventable environmental health hazard that is being increased as the economies expand and paint consumption is increasing. Prior lead paint testing had been performed in Brazil and India and these countries were selected to examine the impact of a new regulatory limit in Brazil and the impact of efforts of non-governmental organizations and others to stop the use of lead compounds in manufacturing paints. Armenia and Kazakhstan, in Central Asia, were selected because nomore » information on lead concentration in those regions was available, no regulatory activities were evident and non-governmental organizations in the IPEN network were available to participate. Another objective of this research was to evaluate the lead loading (µg/cm{sup 2}) limit determined by X-Ray Fluorescence (XRF) for areas on toys that are too small to obtain a sample of sufficient size for laboratory analysis. The lead concentrations in more than three-fourths of the paints from Armenia and Kazakhstan exceeded 90 ppm, the limit in the United States, and 600 ppm, the limit in Brazil. The percentages were about one-half as high in Brazil and India. The average concentration in paints purchased in Armenia, 25,000 ppm, is among the highest that has been previously reported, that in Kazakhstan, 15,700 ppm, and India, 16,600, about median. The average concentration in Brazil, 5600 ppm, is among the lowest observed. Paints in Brazil that contained an average of 36,000 ppm before the regulatory limit became effective were below detection (<9 ppm) in samples collected in the current study. The lack of any apparent public monitoring of paint lead content as part of regulatory enforcement makes it difficult to determine whether the regulation was a major factor contributing to the decline in lead use in these paints. Using data from the current study and those available from other studies 24 of 28 paints from major brands in India decreased from high concentrations to 90 ppm or lower. Since lead concentrations in golden yellow paints from these brands were found to decrease to ≤90 ppm, it is possible that all 28 of these paints now contain ≤90 ppm since yellow paints usually have the highest lead concentrations. Other brands in Brazil and India that have been analyzed only one time had lead concentrations up to 59,000 ppm and 134,000 ppm, respectively. Less than one-third of the paints had notations on their labels with information about lead content and these were sometimes inaccurate. The label from one brand indicating “no added lead” contained paint with 134,000 ppm lead, the highest found in this study. Three percent (3 of 98) of the paints with surface lead loading that did not exceed 2 µg/cm{sup 2}, the limit established by the Consumer Product Safety Improvement Act for small areas on toys, contained greater than 90 ppm lead and thus were false negatives. Of the new paint samples that contained ≤600 ppm, 88% contained ≤90 ppm. Of the samples that contained ≤90 ppm, 97% contained ≤45 ppm and 92% contained ≤15 ppm. Based on these data it appears to be technically feasible to manufacture paints containing ≤90 ppm and in many cases to produce paints that have lead concentrations that do not exceed 15 ppm. - Highlights: • Brazilian paints with high lead (avg. 36,000 ppm) contained <9 ppm after regulation. • Lead in major Indian paint brands decreased to low levels by efforts of NGOs/others. • Most paints with lead ≤600 ppm also are ≤90 ppm and many also ≤15 ppm. • At the CPSIA limit of 2 µg Pb/cm{sup 2} for small areas on toys, 3% exceeded 90 ppm lead. • Most paint brands in Armenia and Kazakhstan based/manufactured outside the country.« less

National Estimate of Per- and Polyfluoroalkyl Substance (PFAS) Release to U.S. Municipal Landfill Leachate.

PubMed

Lang, Johnsie R; Allred, B McKay; Field, Jennifer A; Levis, James W; Barlaz, Morton A

2017-02-21

Landfills are the final stage in the life cycle of many products containing per- and polyfluoroalkyl substances (PFASs) and their presence has been reported in landfill leachate. The concentrations of 70 PFASs in 95 samples of leachate were measured in a survey of U.S. landfills of varying climates and waste ages. National release of PFASs was estimated by coupling measured concentrations for the 19 PFASs where more than 50% of samples had quantifiable concentrations, with climate-specific estimates of annual leachate volumes. For 2013, the total volume of leachate generated in the U.S. was estimated to be 61.1 million m 3 , with 79% of this volume coming from landfills in wet climates (>75 cm/yr precipitation) that contain 47% of U.S. solid waste. The mass of measured PFASs from U.S. landfill leachate to wastewater treatment plants was estimated to be between 563 and 638 kg for 2013. In the majority of landfill leachate samples, 5:3 fluorotelomer carboxylic acid (FTCA) was dominant and variations in concentrations with waste age affected total estimated mass. There were six PFASs that demonstrated significantly higher concentrations in leachate from younger waste compared to older waste and six PFAS demonstrated significant variation with climate.

Micro-PIXE evaluation of radioactive cesium transfer in contaminated soil samples

NASA Astrophysics Data System (ADS)

Fujishiro, F.; Ishii, K.; Matsuyama, S.; Arai, H.; Ishizaki, A.; Osada, N.; Sugai, H.; Kusano, K.; Nozawa, Y.; Yamauchi, S.; Karahashi, M.; Oshikawa, S.; Kikuchi, K.; Koshio, S.; Watanabe, K.; Suzuki, Y.

2014-01-01

Micro-PIXE analysis has been performed on two soil samples with high cesium activity concentrations. These soil samples were contaminated by fallout from the accident at Fukushima Daiichi Nuclear Power Plant. One exhibits a radioactive cesium transfer of ˜0.01, and the other shows a radioactive cesium transfer of less than 0.001, even though both samples have high cesium activity concentrations exceeding 10,000 Bq/kg. X-ray spectra and elemental images of the soil samples revealed the presence of chlorine, which can react with cesium to produce an inorganic soluble compound, and phosphorus-containing cesium-capturable organic compounds.

Variation in aluminum, iron, and particle concentrations in oxic ground-water samples collected by use of tangential-flow ultrafiltration with low-flow sampling

USGS Publications Warehouse

Szabo, Z.; Oden, J.H.; Gibs, J.; Rice, D.E.; Ding, Y.; ,

2001-01-01

Particulates that move with ground water and those that are artificially mobilized during well purging could be incorporated into water samples during collection and could cause trace-element concentrations to vary in unfiltered samples, and possibly in filtered samples (typically 0.45-um (micron) pore size) as well, depending on the particle-size fractions present. Therefore, measured concentrations may not be representative of those in the aquifer. Ground water may contain particles of various sizes and shapes that are broadly classified as colloids, which do not settle from water, and particulates, which do. In order to investigate variations in trace-element concentrations in ground-water samples as a function of particle concentrations and particle-size fractions, the U.S. Geological Survey, in cooperation with the U.S. Air Force, collected samples from five wells completed in the unconfined, oxic Kirkwood-Cohansey aquifer system of the New Jersey Coastal Plain. Samples were collected by purging with a portable pump at low flow (0.2-0.5 liters per minute and minimal drawdown, ideally less than 0.5 foot). Unfiltered samples were collected in the following sequence: (1) within the first few minutes of pumping, (2) after initial turbidity declined and about one to two casing volumes of water had been purged, and (3) after turbidity values had stabilized at less than 1 to 5 Nephelometric Turbidity Units. Filtered samples were split concurrently through (1) a 0.45-um pore size capsule filter, (2) a 0.45-um pore size capsule filter and a 0.0029-um pore size tangential-flow filter in sequence, and (3), in selected cases, a 0.45-um and a 0.05-um pore size capsule filter in sequence. Filtered samples were collected concurrently with the unfiltered sample that was collected when turbidity values stabilized. Quality-assurance samples consisted of sequential duplicates (about 25 percent) and equipment blanks. Concentrations of particles were determined by light scattering. Variations in concentrations aluminum and iron (1 -74 and 1-199 ug/L (micrograms per liter), respectively), common indicators of the presence of particulate-borne trace elements, were greatest in sample sets from individual wells with the greatest variations in turbidity and particle concentration. Differences in trace-element concentrations in sequentially collected unfiltered samples with variable turbidity were 5 to 10 times as great as those in concurrently collected samples that were passed through various filters. These results indicate that turbidity must be both reduced and stabilized even when low-flow sample-collection techniques are used in order to obtain water samples that do not contain considerable particulate artifacts. Currently (2001) available techniques need to be refined to ensure that the measured trace-element concentrations are representative of those that are mobile in the aquifer water.

Evaluation of trace elements in selected foods and dietary intake by young children in Thailand.

PubMed

Nookabkaew, S; Rangkadilok, N; Akib, C A; Tuntiwigit, N; Saehun, J; Satayavivad, J

2013-01-01

Elemental concentrations in rice, animal products, eggs, vegetables, fruits, infant formulas and drinking water were determined in 667 food samples randomly collected from local markets, big supermarkets and grocery stores in Bangkok, Thailand, during the period October 2005-August 2008. Samples were digested with nitric acid and analysed by inductively coupled plasma-mass spectrometry. Arsenic and cadmium levels in most foods were below the maximum levels as set by international organisations. Filtered and bottled drinking water, rice, vegetables and banana contained low concentrations of arsenic, cadmium and lead. Non-polished rice had higher magnesium, calcium, manganese, iron and selenium concentrations than polished rice. Banana was a major source for manganese and selenium. Pig kidney and liver contained high levels of arsenic and cadmium. Manganese, cadmium, lead and aluminium concentrations in soybean milk could also be of concern. With respect to food safety for children, the amounts of arsenic and cadmium ingested with poultry, pig liver or rice corresponded to high weekly or monthly intake.

Patch testing with serial dilutions and thin-layer chromatograms of oak moss absolutes containing high and low levels of atranol and chloroatranol.

PubMed

Mowitz, Martin; Zimerson, Erik; Svedman, Cecilia; Bruze, Magnus

2013-12-01

Oak moss absolute (Evernia prunastri extract) contains a large number of substances, among them the potent allergens atranol and chloroatranol. Since 2008, their content in oak moss absolute has been restricted by the International Fragrance Association to a maximum level of 100 ppm each. To compare the elicitation capacities of a traditional (sample A) and a treated (sample B) oak moss absolute containing, in total, 27 000 and 66 ppm of atranol and chloroatranol, respectively, and to investigate reactions to components of oak moss absolute separated by thin-layer chromatography (TLC). Fifteen oak moss-allergic subjects were patch tested with serial dilutions and TLC strips of samples A and B. Fifteen subjects reacted to sample A at concentrations ≤ 2.0%, and 2 subjects reacted to sample B at 2.0% but not to lower concentrations. Among 13 subjects reacting to the TLC strip of sample A, 11 reacted to spots with retardation factor values corresponding to those of atranol and/or chloroatranol, and 11 reacted to other areas on the TLC strip. Only one subject reacted to the TLC strip of sample B. The patch test reactivity of sample B was significantly lower than that of sample A. The TLC patch tests indicate the presence of sensitizers other than atranol and chloroatranol in oak moss absolute. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The Effect of Sedimentation Conditions of Frozen Deposits at the Kolyma Lowland on the Distribution of Methane and Microorganisms Activity

NASA Astrophysics Data System (ADS)

Oshurkova, V.; Kholodov, A. L.; Spektor, V.; Sherbakova, V.; Rivkina, E.

2014-12-01

Biogeochemical and microbiological investigations of methane distribution and origin in Northeastern Arctic permafrost sediments indicated that microbial methane production was observed in situ in thawed and permanently frozen deposits (Rivkina et al., 2007). To check the hypothesis about the correlation between permafrost ground type and quantity of methane, produced by microorganisms, the samples from deposits of thermokarst depression (alas), Yedoma and fluvial deposits of Kolyma floodplain for gas measurements and microbiological study were collected and the experiment with anaerobic incubation was conducted. Gas analysis indicated that alas and floodplain samples were characterized by high methane concentrations whereas Yedoma samples had only traces of methane. Two media with different substrates were prepared anaerobically for incubation. First medium contained sucrose as a substrate for hydrolytic microflora and the second one contained acetate as a substrate for methanogens. Two samples from alas, one sample from Yedoma and one from floodplain were placed in anaerobic bottles and media under gas mixture (N2, CO2 and H2) were added. The bottles were incubated for 2 weeks at room temperature. The results of the experiment showed that there was the increase of methane concentrations in the bottles with Yedoma and Floodplain samples to 52-60 and 67-90 %, respectively, from initial concentrations in contrast with Alas sample inoculated bottles. At the same time the concentration of methane in control bottles, which did not include substrates, increased to 15-19%. Current research is a part of NSF funded project "The Polaris".

Characterization of the natural radioactivity of the first deep geothermal doublet in Flanders, Belgium.

PubMed

Vasile, M; Bruggeman, M; Van Meensel, S; Bos, S; Laenen, B

2017-08-01

Deep geothermal energy is a local energy resource that is based on the heat generated by the Earth. As the heat is continuously regenerated, geothermal exploitation can be considered as a renewable and, depending on the techniques used, a sustainable energy production system. In September 2015, the Flemish Institute for Technological Research (VITO) started drilling an exploration well targeting a hot water reservoir at a depth of about 3km on the Balmatt site near Mol. Geothermal hot water contains naturally occurring gases, chemicals and radionuclides at variable concentrations. The actual concentrations and potentially related hazards strongly depend on local geological and hydrogeological conditions. This paper summarizes the radiological characterization of several rock samples obtained from different depths during the drilling, the formation water, the salt and the sediment fraction. The results of our analyses show low values for the activity concentration for uranium and thorium in the formation water and in the precipitate/sediment fraction. Also, the activity concentrations of 210 Pb and 210 Po are low in these samples and the activity concentration of 226 Ra is dominant. From the analysis of the rock samples, it was found that the layer above the reservoir has a higher uranium and thorium concentration than the layer of the reservoir, which on the other hand contains more radium than the layer above it. Copyright © 2016 Elsevier Ltd. All rights reserved.

Long-Range Transport of Perchlorate Observed in the Atmospheric Aerosols Collected at Okinawa Island, Japan

NASA Astrophysics Data System (ADS)

Handa, D.; Okada, K.; Kuroki, Y.; Nakama, Y.; Nakajima, H.; Arakaki, T.; Tanahara, A.; Oomori, T.; Miyagi, T.; Kadena, H.; Ishizaki, T.; Nakama, F.

2007-12-01

The study of perchlorate has become quite active in the U.S. in the last several years. Perchlorate has been recognized as a new environmental pollutant and it attracted much attention quickly in the world. The health concern about perchlorate stems from the fact that it displaces iodide in the thyroid gland, while iodine-containing thyroid hormones are essential for proper neural development from the fetal stage through the first years of life. In this study, we determined the concentrations of perchlorate ion present in the atmospheric aerosols collected in Okinawa Island, Japan. We then examined the relationships between the perchlorate concentrations and the environmental parameters and the climatic conditions peculiar to Okinawa. Bulk aerosol samples were collected on quartz filters by using a high volume air sampler at Cape Hedo Atmosphere and Aerosol Monitoring Station (CHAAMS). Each sampling duration was one week. The quartz filters with aerosols were stirred with Milli-Q pure water for three hours before perchlorate ion was extracted. The extracted perchlorate ion concentrations were determined by ion chromatography (ICS-2000, DIONEX). The mean perchlorate concentration for the samples collected at CHAAMS was 1.83 ng/m3, and the minimum was 0.18 ng/m3. The samples collected during November 21-27, 2005, January 23-30, 2006 and April 24-01, 2006 had highest perchlorate concentrations. For these three samples, we performed back trajectory analysis, and found that the air mass for the three samples arrived from the Asian continent. A relatively strong correlation (r2 = 0.55) was found between perchlorate and nss-sulfate concentrations for the CHAAMS samples. Furthermore, we analyzed perchlorate in the soils and the fertilizers used for sugar cane farming around the CHAAMS area. The Milli-Q extract of the soil and the fertilizers did not contain any detectable levels of perchlorate ions. Therefore, it was suggested that perchlorate found in the atmospheric aerosols collected at CHAAMS was probably transported from the Asian continent.

Headspace concentrations of explosive vapors in containers designed for canine testing and training: theory, experiment, and canine trials.

PubMed

Lotspeich, Erica; Kitts, Kelley; Goodpaster, John

2012-07-10

It is a common misconception that the amount of explosive is the chief contributor to the quantity of vapor that is available to trained canines. In fact, this quantity (known as odor availability) depends not only on the amount of explosive material, but also the container volume, explosive vapor pressure and temperature. In order to better understand odor availability, headspace experiments were conducted and the results were compared to theory. The vapor-phase concentrations of three liquid explosives (nitromethane, nitroethane and nitropropane) were predicted using the Ideal Gas Law for containers of various volumes that are in use for canine testing. These predictions were verified through experiments that varied the amount of sample, the container size, and the temperature. These results demonstrated that the amount of sample that is needed to saturate different sized containers is small, predictable and agrees well with theory. In general, and as expected, once the headspace of a container is saturated, any subsequent increase in sample volume will not result in the release of more vapors. The ability of canines to recognize and alert to differing amounts of nitromethane has also been studied. In particular, it was found that the response of trained canines is independent of the amount of nitromethane present, provided it is a sufficient quantity to saturate the container in which it is held. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Aluminium content of some processed foods, raw materials and food additives in China by inductively coupled plasma-mass spectrometry.

PubMed

Deng, Gui-Fang; Li, Ke; Ma, Jing; Liu, Fen; Dai, Jing-Jing; Li, Hua-Bin

2011-01-01

The level of aluminium in 178 processed food samples from Shenzhen city in China was evaluated using inductively coupled plasma-mass spectrometry. Some processed foods contained a concentration of up to 1226 mg/kg, which is about 12 times the Chinese food standard. To establish the main source in these foods, Al levels in the raw materials were determined. However, aluminium concentrations in raw materials were low (0.10-451.5 mg/kg). Therefore, aluminium levels in food additives used in these foods was determined and it was found that some food additives contained a high concentration of aluminium (0.005-57.4 g/kg). The results suggested that, in the interest of public health, food additives containing high concentrations of aluminium should be replaced by those containing less. This study has provided new information on aluminium levels in Chinese processed foods, raw materials and a selection of food additives.

Study of contaminant transport at an open-tipping waste disposal site.

PubMed

Ashraf, Muhammad Aqeel; Yusoff, Ismail; Yusof, Mohamad; Alias, Yatimah

2013-07-01

Field and laboratory studies were conducted to estimate concentration of potential contaminants from landfill in the underlying groundwater, leachate, and surface water. Samples collected in the vicinity of the landfill were analyzed for physiochemical parameters, organic contaminants, and toxic heavy metals. Water quality results obtained were compared from published data and reports. The results indicate serious groundwater and surface water contamination in and around the waste disposal site. Analysis of the organic samples revealed that the site contains polychlorinated biphenyls and other organo-chlorine chemicals, principally chloro-benzenes. Although the amount of PCB concentration discovered was not extreme, their presence indicates a potentially serious environmental threat. Elevated concentrations of lead, copper, nickel, manganese, cadmium, and cobalt at the downgradient indicate that the contamination plume migrated further from the site, and the distribution of metals and metals containing wastes in the site is nonhomogeneous. These results clearly indicate that materials are poorly contained and are at risk of entering the environment. Therefore, full characterization of the dump contents and the integrity of the site are necessary to evaluate the scope of the problem and to identify suitable remediation options.

Measurement of radon concentration in water using the portable radon survey meter.

PubMed

Yokoyama, S; Mori, N; Shimo, M; Fukushi, M; Ohnuma, S

2011-07-01

A measurement method for measuring radon in water using the portable radon survey meter (RnSM) was developed. The container with propeller was used to stir the water samples and release radon from the water into the air in a sample box of the RnSM. In this method, the measurement of error would be <20 %, when the radon concentration in the mineral water was >20 Bq l(-1).

Elution of platinum from carboplatin-impregnated calcium sulfate hemihydrate beads in vitro.

PubMed

Tulipan, Rachel J; Phillips, Heidi; Garrett, Laura D; Dirikolu, Levent; Mitchell, Mark A

2016-11-01

OBJECTIVE To characterize the elution of platinum from carboplatin-impregnated calcium sulfate hemihydrate (CSH) beads in vitro. SAMPLE 60 carboplatin-impregnated CSH beads and 9 CSH beads without added carboplatin (controls). PROCEDURES Carboplatin-impregnated CSH beads (each containing 4.6 mg of carboplatin [2.4 mg of platinum]) were placed into separate 10-mL plastic tubes containing 5 mL of PBSS in groups of 1, 3, 6, or 10; 3 control beads were placed into a single tube of PBSS at the same volume. Experiments were conducted in triplicate at 37°C and a pH of 7.4 with constant agitation. Eluent samples were collected at 1, 2, 3, 6, 12, 24, and 72 hours. Samples were analyzed for platinum content by inductively coupled plasma-mass spectrometry. RESULTS The mean concentration of platinum released per carboplatin-impregnated bead over 72 hours was 445.3 mg/L. Cumulative concentrations of platinum eluted increased as the number of beads per tube increased. There was a significant difference in platinum concentrations over time, with values increasing over the first 12 hours and then declining for all tubes. There was also a significant difference in percentage of total incorporated platinum released into tubes with different numbers of beads: the percentage of eluted platinum was higher in tubes containing 1 or 3 beads than in those containing 6 or 10 beads. CONCLUSIONS AND CLINICAL RELEVANCE Carboplatin-impregnated CSH beads eluted platinum over 72 hours. Further studies are needed to determine whether implantation of carboplatin-impregnated CSH beads results in detectable levels of platinum systemically and whether the platinum concentrations eluted locally are toxic to tumor cells.

Positive anomalous concentrations of Pb in some gabbroic rocks of Afikpo basin southeastern Nigeria.

PubMed

Onwualu-John, J N

2016-08-01

Gabbroic rocks have intruded the sedimentary sequence at Ameta in Afikpo basin southeastern Nigeria. Petrographic and geochemical features of the rocks were studied in order to evaluate their genetic and geotectonic history. The petrographic results show that the rocks contain plagioclase, olivine, pyroxene, biotite, iron oxide, and traces of quartz in three samples. Major element characteristics show that the rocks are subalkaline. In addition, the rocks have geochemical characteristics similar to basaltic andesites. The trace elements results show inconsistent concentrations of high field strength elements (Zr, Nb, Th, Ta), moderate enrichment of large-ion lithophile elements (Rb, Sr, Ba) and low concentrations of Ni and Cr. Rare earth element results show that the rocks are characterized by enrichment of light rare earth elements, middle rare earth elements enrichment, and depletion of heavy rare earth elements with slight positive europium anomalies. Zinc concentrations are within the normal range in basaltic rocks. There are extremely high concentrations of Pb in three of the rock samples. The high Pb concentrations in some of these rocks could be as a result of last episodes of magmatic crystallization. The rocks intruded the Asu River Group; organic components in the sedimentary sequence probably contain Pb which has been assimilated into the magma at the evolutionary stage of the magma. Weathering of some rocks that contain galena could lead to an increase in the concentration of lead in the gabbroic rocks, especially when the migration and crystallization of magma take place in an aqueous environment. Nevertheless, high concentration of lead is hazardous to health and environment.

Occurrence and concentrations of selected trace elements, halogenated organic compounds, and polycyclic aromatic hydrocarbons in streambed sediments and results of water-toxicity testing in Westside Creeks and the San Antonio River, San Antonio, Texas, 2014

USGS Publications Warehouse

Crow, Cassi L.; Wilson, Jennifer T.; Kunz, James L.

2016-12-01

Sediment samples and samples for water-toxicity testing were collected during 2014 from several streams in San Antonio, Texas, known locally as the Westside Creeks (Alazán, Apache, Martínez, and San Pedro Creeks) and from the San Antonio River. Samples were collected during base flow and after periods of stormwater runoff (poststorm conditions) to determine baseline sediment- and water-quality conditions. Streambed-sediment samples were analyzed for selected constituents, including trace elements and organic contaminants such as pesticides, polychlorinated biphenyls (PCBs), brominated flame retardants, and polycyclic aromatic hydrocarbons (PAHs). Potential risks of contaminants in sediment were evaluated by comparing concentrations of contaminants in sediment to two effects-based sediment-quality guidelines: (1) a lower level, called the threshold effect concentration, below which, harmful effects to benthic biota are not expected, and (2) a higher level, the probable effect concentration (PEC), above which harmful effects are expected to occur frequently. Samples for water-toxicity testing were collected from each stream to provide information about fish toxicity in the study area. The trace metal lead was detected at potentially toxic concentrations greater than the PEC in both the base-flow and poststorm samples collected at two sites sampled on San Pedro Creek. The PECs for the pesticides dichlorodiphenyldichloroethane, dichlorodiphenyldichloroethylene, dichlorodiphenyltrichloroethane, and chlordane were exceeded in some of the samples at the same two sites on San Pedro Creek. Brominated flame retardants and polybrominated diphenyl ether (PBDE) 85, 153, and 154 were found in all streambed-sediment samples. Federal Environmental Quality Guidelines established by Environment Canada for PBDE 99 and PBDE 100 were exceeded in all samples in which PBDE 99 was detected and in a majority of the samples in which PBDE 100 was detected; the greatest concentrations occurred in samples collected at the same two sites on San Pedro Creek where the samples containing elevated lead and pesticide concentrations were collected. All concentrations of total PCBs (computed as the sum of the 18 reported PCB congeners) in the individual streambed-sediment samples were less than the threshold effect concentration, but the concentrations were elevated in the two sites on San Pedro Creek compared to concentrations at other sites. At one site on Apache Creek, 6 of the individual PAHs measured in the sample collected during base-flow conditions exceeded the PECs and 8 of the 9 PECs were exceeded in the sample collected during poststorm conditions. The total PAH concentration in the sample collected at the site during poststorm conditions was 3.3 times greater than the PEC developed for total PAHs. Average PAH profiles computed for base-flow samples and poststorm samples most closely resemble the parking lot coal-tar sealcoat dust PAH source profile, defined as the average PAH concentrations in dust swept from parking lots in six cities in the United States that were sealed with a black, viscous liquid containing coal-tar pitch. Six of ten water samples collected during base-flow conditions caused reductions in Pimephales promelas (fathead minnow) survival and were considered to be toxic.

Determination of biogenic amine profiles in conventional and organic cocoa-based products.

PubMed

Restuccia, Donatella; Spizzirri, U Gianfranco; Puoci, Francesco; Picci, Nevio

2015-01-01

Cocoa contains many compounds such as biogenic amines (BAs), known to influence consumer health. Spermidine, spermidine, putrescine, histamine, tyramine, β-phenylethylamine, cadaverine and serotonine have been found in several cocoa-based products using HPLC with UV detection after derivatisation with dansyl-chloride. Once optimised in terms of linearity, percentage recovery, LOD, LOQ and repeatability, this method was applied to real samples. Total concentrations of BAs ranged from 5.7 to 79.0 µg g(-)(1) with wide variations depending on the type of sample. BAs present in all samples were in decreasing order: histamine (1.9-38.1 µg g(-)(1)) and tyramine (1.7-31.7 µg g(-)(1)), while putrescine (0.9-32.7 µg g(-)(1)), spermidine (1.0-9.7 µg g(-)(1)) and spermidine (0.6-9.3 µg g(-)(1)) were present in most of the samples. Cadaverine, serotonine and β-phenylethylamine were present in a few samples at much lower concentrations. Organic samples always contained much lower levels of BAs than their conventional counterparts and, generally speaking, the highest amounts of BAs were found in the most processed products.

Ground-water appraisal in northwestern Big Stone County, west-central Minnesota

USGS Publications Warehouse

Soukup, W.G.

1980-01-01

Samples of water were collected for chemical analysis from wells in the surficial outwash, buried outwash, and Cretaceous aquifers. With the exception of nitrate, the greatest difference in chemical quality was between samples from the buried outwash and Cretaceous aquifers. Water from Cretaceous aquifers is softer than water from the outwash aquifers, but contains concentrations of sodium and boron that are high enough to damage soils and crops if used for irrigation. Nitrate concentrations exceeded the Minnesota Pollution Control Agency's recommended limits for drinking water in one sample from the surficial aquifer.

A unique approach to determine the ice nucleating potential of soot-containing aerosol from biomass combustion

NASA Astrophysics Data System (ADS)

Levin, E. J.; McMeeking, G. R.; McCluskey, C.; DeMott, P. J.; Kreidenweis, S. M.

2013-12-01

Ice nucleating particles (INP) play a crucial role in cloud and precipitation development in mixed phase clouds by catalyzing ice formation at temperatures warmer than -36 C. Despite their importance, however, there is still considerable uncertainty as to the sources and chemical nature of INP. Water insoluble particles such as mineral dust and certain biological aerosols have been shown to be efficient ice nuclei, and soot particles have also been suggested as potential INP. Biomass burning, such as wildfires and prescribed burning, is a large contributor to atmospheric soot concentrations, and could therefore be a potentially important source of INP. Both laboratory and field studies have detected enhanced INP concentrations in smoke plumes; however, the chemical composition of these INP is still uncertain as fires emit and loft a complex mixture of aerosol particles. In this work we employ a novel approach to selectively remove soot aerosol from the sample stream to determine the specific contribution of soot to INP concentrations. A number of commonly consumed biomass fuels were burned in the U.S. Forest Service combustion laboratory during the FLAME-4 (Fire Laboratory At Missoula Experiment - 4) study. Number concentrations of INP acting in the condensation and immersion freezing modes and total aerosol greater than 500 nm in diameter (N500) were measured using the Colorado State University Continuous Flow Diffusion Chamber (CFDC). To determine the contribution of soot to INP concentrations, the sample stream was passed through a Single Particle Soot Photometer (SP2; Droplet Measurement Technologies) which employs laser induced incandescence (LII) to detect soot containing particles and total soot mass. During LII, soot containing particles are vaporized and removed from the sample while non-soot containing particles pass through the instrument unaffected. By sampling the exhaust of the SP2 with the CFDC and alternately cycling laser power on and off we were able to estimate the contribution of soot to total INP. Reductions in both N500 and INP were observed when the laser power was on, indicating both the presence of soot in the total aerosol and the INP fraction of these particles. However, considerable variability was observed in the fraction of INP composed of soot-containing particles with a range from ~0 - 70% for the biomass types and combustion conditions examined.

Total mercury in canned tuna sold in Canada in 2006.

PubMed

Dabeka, Robert W; Mckenzie, Arthur D; Forsyth, Donald S

2014-01-01

Total mercury was measured in 156 composites prepared from 936 samples of canned tuna sold in Canada in 2006. Each composite comprised a single brand. Yellowfin tuna contained the lowest concentrations, averaging 0.066 mg/kg. Skipjack tuna contained slightly higher concentrations, averaging 0.132 mg/kg. The highest average concentration was found in the Albacore tuna: mean 0.325 mg/kg, range 0.174-0.507 mg/kg. The second highest concentration among the 49 albacore composites was 0.469 mg/kg. There were 72 composites for which the type of tuna was not specified. The mercury in these averaged 0.095 mg/kg and ranged from 0.016 to 0.237 mg/kg.

Ground-water quality and its relation to hydrogeology, land use, and surface-water quality in the Red Clay Creek basin, Piedmont Physiographic Province, Pennsylvania and Delaware

USGS Publications Warehouse

Senior, Lisa A.

1996-01-01

The Red Clay Creek Basin in the Piedmont Physiographic Province of Pennsylvania and Delaware is a 54-square-mile area underlain by a structurally complex assemblage of fractured metamorphosed sedimentary and igneous rocks that form a water-table aquifer. Ground-water-flow systems generally are local, and ground water discharges to streams. Both ground water and surface water in the basin are used for drinking-water supply.Ground-water quality and the relation between ground-water quality and hydrogeologic and land-use factors were assessed in 1993 in bedrock aquifers of the basin. A total of 82 wells were sampled from July to November 1993 using a stratified random sampling scheme that included 8 hydrogeologic and 4 land-use categories to distribute the samples evenly over the area of the basin. The eight hydrogeologic units were determined by formation or lithology. The land-use categories were (1) forested, open, and undeveloped; (2) agricultural; (3) residential; and (4) industrial and commercial. Well-water samples were analyzed for major and minor ions, nutrients, volatile organic compounds (VOC's), pesticides, polychlorinated biphenyl compounds (PCB's), and radon-222.Concentrations of some constituents exceeded maximum contaminant levels (MCL) or secondary maximum contaminant levels (SMCL) established by the U.S. Environmental Protection Agency for drinking water. Concentrations of nitrate were greater than the MCL of 10 mg/L (milligrams per liter) as nitrogen (N) in water from 11 (13 percent) of 82 wells sampled; the maximum concentration was 38 mg/L as N. Water from only 1 of 82 wells sampled contained VOC's or pesticides that exceeded a MCL; water from that well contained 3 mg/L chlordane and 1 mg/L of PCB's. Constituents or properties of well-water samples that exceeded SMCL's included iron, manganese, dissolved solids, pH, and corrosivity. Water from 70 (85 percent) of the 82 wells sampled contained radon-222 activities greater than the proposed MCL of 300 pCi/L (picoCuries per liter).Differences in selected major and minor ion concentrations and radon-222 activities were statistically significant between some lithologies and are related to differences in mineralogy. Ground water from felsic gneiss and schist generally contained higher radon-222 activities than the other lithologies; activities as high as 10,000 pCi/L were measured in a water sample from the felsic gneiss.Differences in the concentrations of nitrate, sodium, and chloride, and the frequency of pesticide detections in ground water were statistically significant between samples from wells in some land-use categories. Concentrations of nitrate generally were greatest in agricultural and in industrial and commercial areas and can be attributed to the use of fertilizers on the land surface and other agricultural activities. Much of the industrial and commercial land use is in areas previously used for or related to mushroom production. Concentrations of chloride and sodium also were greatest in water from wells in agricultural and industrial and commercial areas, probably because of the use of fertilizer and road salt. Concentrations of nitrate, chloride, and sodium in water samples from wells in forested and residential land use did not differ statistically significantly from each other. The herbicides metolachlor and atrazine were the most frequently detected pesticides and were detected more frequently in agricultural areas than in areas with other land uses; their presence is related to their use in crop production. VOC's were detected infrequently and only in residential and industrial and commercial areas.The relation between ground-water quality and surface-water quality is assessed by comparing nitrate and chloride concentrations in the 1993 ground-water samples and 1993-94 base-flow samples. Base-flow samples were collected at eight stream sites in the headwaters of the West Branch of Red Clay Creek in 1994 and at two long-term stream-monitoing sites on the East and West Branches of the Red Clay Creek in 1993-94. The average concentrations of chloride and nitrate in ground-water samples from wells in areas above the headwater stream sites and two long-term stream-monitoring sites were similar to the concentrations of chloride and nitrate in base flow at those sites. An observed increase in nitrate concentration in base flow at the long-term monitoring site on the West Branch of Red Clay Creek from 1970 to 1995 may be related to an increase in nitrate concentrations in ground water in that area of the basin.

Optical and Electron Spin Resonance Studies of Destruction of Porous Structures Formed by Nitrogen-Rare Gas Nanoclusters in Bulk Superfluid Helium

NASA Astrophysics Data System (ADS)

McColgan, Patrick T.; Meraki, Adil; Boltnev, Roman E.; Lee, David M.; Khmelenko, Vladimir V.

2017-04-01

We studied optical and electron spin resonance spectra during destruction of porous structures formed by nitrogen-rare gas (RG) nanoclusters in bulk superfluid helium containing high concentrations of stabilized nitrogen atoms. Samples were created by injecting products of a radio frequency discharge of nitrogen-rare gas-helium gas mixtures into bulk superfluid helium. These samples have a high energy density allowing the study of energy release in chemical processes inside of nanocluster aggregates. The rare gases used in the studies were neon, argon, and krypton. We also studied the effects of changing the relative concentrations between nitrogen and rare gas on thermoluminescence spectra during destruction of the samples. At the beginning of the destructions, α -group of nitrogen atoms, Vegard-Kaplan bands of N_2 molecules, and β -group of O atoms were observed. The final destruction of the samples were characterized by a series bright flashes. Spectra obtained during these flashes contain M- and β -bands of NO molecules, the intensities of which depend on the concentration of molecular nitrogen in the gas mixture as well as the type of rare gas present in the gas mixture.

A magnetic bead-based method for concentrating DNA from human urine for downstream detection.

PubMed

Bordelon, Hali; Russ, Patricia K; Wright, David W; Haselton, Frederick R

2013-01-01

Due to the presence of PCR inhibitors, PCR cannot be used directly on most clinical samples, including human urine, without pre-treatment. A magnetic bead-based strategy is one potential method to collect biomarkers from urine samples and separate the biomarkers from PCR inhibitors. In this report, a 1 mL urine sample was mixed within the bulb of a transfer pipette containing lyophilized nucleic acid-silica adsorption buffer and silica-coated magnetic beads. After mixing, the sample was transferred from the pipette bulb to a small diameter tube, and captured biomarkers were concentrated using magnetic entrainment of beads through pre-arrayed wash solutions separated by small air gaps. Feasibility was tested using synthetic segments of the 140 bp tuberculosis IS6110 DNA sequence spiked into pooled human urine samples. DNA recovery was evaluated by qPCR. Despite the presence of spiked DNA, no DNA was detectable in unextracted urine samples, presumably due to the presence of PCR inhibitors. However, following extraction with the magnetic bead-based method, we found that ∼50% of spiked TB DNA was recovered from human urine containing roughly 5×10(3) to 5×10(8) copies of IS6110 DNA. In addition, the DNA was concentrated approximately ten-fold into water. The final concentration of DNA in the eluate was 5×10(6), 14×10(6), and 8×10(6) copies/µL for 1, 3, and 5 mL urine samples, respectively. Lyophilized and freshly prepared reagents within the transfer pipette produced similar results, suggesting that long-term storage without refrigeration is possible. DNA recovery increased with the length of the spiked DNA segments from 10±0.9% for a 75 bp DNA sequence to 42±4% for a 100 bp segment and 58±9% for a 140 bp segment. The estimated LOD was 77 copies of DNA/µL of urine. The strategy presented here provides a simple means to achieve high nucleic acid recovery from easily obtained urine samples, which does not contain inhibitors of PCR.

A Magnetic Bead-Based Method for Concentrating DNA from Human Urine for Downstream Detection

PubMed Central

Bordelon, Hali; Russ, Patricia K.; Wright, David W.; Haselton, Frederick R.

2013-01-01

Due to the presence of PCR inhibitors, PCR cannot be used directly on most clinical samples, including human urine, without pre-treatment. A magnetic bead-based strategy is one potential method to collect biomarkers from urine samples and separate the biomarkers from PCR inhibitors. In this report, a 1 mL urine sample was mixed within the bulb of a transfer pipette containing lyophilized nucleic acid-silica adsorption buffer and silica-coated magnetic beads. After mixing, the sample was transferred from the pipette bulb to a small diameter tube, and captured biomarkers were concentrated using magnetic entrainment of beads through pre-arrayed wash solutions separated by small air gaps. Feasibility was tested using synthetic segments of the 140 bp tuberculosis IS6110 DNA sequence spiked into pooled human urine samples. DNA recovery was evaluated by qPCR. Despite the presence of spiked DNA, no DNA was detectable in unextracted urine samples, presumably due to the presence of PCR inhibitors. However, following extraction with the magnetic bead-based method, we found that ∼50% of spiked TB DNA was recovered from human urine containing roughly 5×103 to 5×108 copies of IS6110 DNA. In addition, the DNA was concentrated approximately ten-fold into water. The final concentration of DNA in the eluate was 5×106, 14×106, and 8×106 copies/µL for 1, 3, and 5 mL urine samples, respectively. Lyophilized and freshly prepared reagents within the transfer pipette produced similar results, suggesting that long-term storage without refrigeration is possible. DNA recovery increased with the length of the spiked DNA segments from 10±0.9% for a 75 bp DNA sequence to 42±4% for a 100 bp segment and 58±9% for a 140 bp segment. The estimated LOD was 77 copies of DNA/µL of urine. The strategy presented here provides a simple means to achieve high nucleic acid recovery from easily obtained urine samples, which does not contain inhibitors of PCR. PMID:23861895

Surveys of rice sold in Canada for aflatoxins, ochratoxin A and fumonisins

PubMed Central

Bansal, J.; Pantazopoulos, P.; Tam, J.; Cavlovic, P.; Kwong, K.; Turcotte, A.-M.; Lau, B.P.-Y.; Scott, P.M.

2011-01-01

Approximately 200 samples of rice (including white, brown, red, black, basmati and jasmine, as well as wild rice) from several different countries, including the United States, Canada, Pakistan, India and Thailand, were analysed for aflatoxins, ochratoxin A (OTA) and fumonisins by separate liquid Chromatographic methods in two different years. The mean concentrations for aflatoxin B1 (AFB1) were 0.19 and 0.17 ng g−1 with respective positive incidences of 56% and 43% (≥ the limit of detection (LOD) of 0.002 ng g−1). Twenty-three samples analysed in the second year also contained aflatoxin B2 (AFB2) at levels ≥LOD of 0.002 ng g−1 The five most contaminated samples in each year contained 1.44–7.14 ng AFB1 g−1 (year 1) and 1.45–3.48 ng AFB1 g−1 (year 2); they were mostly basmati rice from India and Pakistan and black and red rice from Thailand. The average concentrations of ochratoxin A (OTA) were 0.05 and 0.005 ng g−1 in year 1 and year 2, respectively; incidences of samples containing ≥LOD of 0.05 ng g−1 were 43% and 1%, respectively, in the 2 years. All positive OTA results were confirmed by LC-MS/MS. For fumonisins, concentrations of fumonisin B1 (FB1) averaged 4.5 ng g−1 in 15 positive samples (≥0.7 ng g−1) from year 1 (n = 99); fumonisin B2 (FB2) and fumonisin B3 (FB3) were also present (≥1 ng g−1). In the second year there was only one positive sample (14 ng g−1 FB1) out of 100 analysed. All positive FB1 results were confirmed by LC-MS/MS. PMID:21623501

Occurrence of organic wastewater compounds in effluent-dominated streams in Northeastern Kansas

USGS Publications Warehouse

Lee, C.J.; Rasmussen, T.J.

2006-01-01

Fifty-nine stream-water samples and 14 municipal wastewater treatment facility (WWTF) discharge samples in Johnson County, northeastern Kansas, were analyzed for 55 compounds collectively described as organic wastewater compounds (OWCs). Stream-water samples were collected upstream, in, and downstream from WWTF discharges in urban and rural areas during base-flow conditions. The effect of secondary treatment processes on OWC occurrence was evaluated by collecting eight samples from WWTF discharges using activated sludge and six from WWTFs samples using trickling filter treatment processes. Samples collected directly from WWTF discharges contained the largest concentrations of most OWCs in this study. Samples from trickling filter discharges had significantly larger concentrations of many OWCs (p-value < 0.05) compared to samples collected from activated sludge discharges. OWC concentrations decreased significantly in samples from WWTF discharges compared to stream-water samples collected from sites greater than 2000??m downstream. Upstream from WWTF discharges, base-flow samples collected in streams draining predominantly urban watersheds had significantly larger concentrations of cumulative OWCs (p-value = 0.03), caffeine (p-value = 0.01), and tris(2-butoxyethyl) phosphate (p-value < 0.01) than those collected downstream from more rural watersheds.

Alpha-PVP as an active component of herbal highs in Poland between 2013 and 2015.

PubMed

Byrska, Bogumiła; Stanaszek, Roman; Zuba, Dariusz

2017-08-01

Alpha-PVP (alpha-pyrrolidinovalerophenone, α-PVP) is a synthetic derivative of cathinone. It has been one of the most frequently detected new psychoactive substances (NPS) available on the drug market in recent years in Poland. The usual routes of administration of the drug include oral, insufflation, and injection. Unexpectedly, we dealt with a great number of herbal samples that turned out to contain α-PVP. A total number of 352 herbal samples from 19 cases in which we detected synthetic cathinones, were investigated in the Institute of Forensic Research (IFR) from 2013 to 2015. The seized products that were received by our laboratory were first screened by gas chromatography coupled to mass spectrometry (GC-MS). Quantification of α-PVP and other cathinones was performed by ultra-performance liquid chromatography with photodiode array detection (UPLC-PDA). Of the samples, 84% contained only α-PVP. Other groups of products were those containing only α-PVT, α-PVP and α-PVT, α-PVP and synthetic cannabinoid A-834, 735, and α-PVP and cannabis. In one herbal sample, α-PVP was detected along with caffeine and tadalafil. The herbal products present on the market containing only α-PVP usually had a mass of 0.3 to 0.6 g, and concentration range in this group of samples was 3.0-44.0% (content: 13.0-222.0 mg per package). The amount of α-PVP in samples below 0.30 g was in a range 9-18 mg whiles in samples above 0.60 g it was in the range 30-716 mg. There were also products containing a mixture of α-PVP and α-PVT. In those samples, α-PVP concentrations were: 3.0-6.0% (amount: 15.0-34.0 mg). Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Field investigation of the quality of fresh and aged leachates from selected landfills receiving e-waste in an arid climate.

PubMed

Kiddee, Peeranart; Naidu, Ravi; Wong, Ming H; Hearn, Laurence; Muller, Jochen F

2014-11-01

The management of electronic waste (e-waste) is a serious problem worldwide and much of it is landfilled. A survey of four selected landfills in an arid region of South Australia was conducted to determine the proportion of e-waste in municipal waste and the properties of each landfill site. Leachate and groundwater samples were collected upgradient and downgradient of the landfills for analysis of polybrominated diphenyl ethers (PBDEs) and 14 metals and metalloids, including Al, As, Ba, Be, Cd, Co, Cr, Cu, Fe, Ni, Pb, Sb, V and Zn. Our data demonstrate that the selected landfills in South Australia continue to receive municipal waste containing in excess of 6%, or 25,000 tonnes per year, of e-waste. The leachates and groundwater collected from the landfills contained significantly elevated concentrations of Pb with the highest concentration in groundwater of 38 μg/l, almost four times higher than the Australian drinking water guideline of 10 μg/l. The presence of PBDEs was detected in both leachate and groundwater samples. Total PBDEs values of 2.13-59.75 ng/l in leachate samples were 10 times higher than in groundwater samples, which recorded a range of 0.41-6.53 ng/l at all sites. Moreover, the concentrations of metals and metalloids in sampled groundwater contained elevated levels of Al, As, Fe, Ni and Pb that exceeded Australian drinking water guideline values. For these reasons potential leaching of these contaminants is of concern and while difficult to attribute elevated contaminant levels to e-waste, we do not recommend continued disposal of e-waste in old landfills that were not originally designed to contain leachates. The survey also revealed temporal variation in the electrical conductivity and concentrations of As, Cd and Pb present in leachates of landfills in arid Mediterranean climates. These results are consistent with the marked variations in rainfall patterns observed for such climates. The solute concentration (EC and other ions including As, Cd and Pb) declines in the leachates during wet winter months (June to September), in contrast to tropical countries where such changes are observed during wet summer months. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

Metal concentrations in schoolyard soils from New Orleans, Louisiana before and after Hurricanes Katrina and Rita.

PubMed

Presley, Steven M; Abel, Michael T; Austin, Galen P; Rainwater, Thomas R; Brown, Ray W; McDaniel, Les N; Marsland, Eric J; Fornerette, Ashley M; Dillard, Melvin L; Rigdon, Richard W; Kendall, Ronald J; Cobb, George P

2010-06-01

The long-term environmental impact and potential human health hazards resulting from Hurricanes Katrina and Rita throughout much of the United States Gulf Coast, particularly in the New Orleans, Louisiana, USA area are still being assessed and realized after more than four years. Numerous government agencies and private entities have collected environmental samples from throughout New Orleans and found concentrations of contaminants exceeding human health screening values as established by the United States Environmental Protection Agency (USEPA) for air, soil, and water. To further assess risks of exposure to toxic concentrations of soil contaminants for citizens, particularly children, returning to live in New Orleans following the storms, soils collected from schoolyards prior to Hurricane Katrina and after Hurricane Rita were screened for 26 metals. Concentrations exceeding USEPA Regional Screening Levels (USEPA-RSL), total exposure, non-cancer endpoints, for residential soils for arsenic (As), iron (Fe), lead (Pb), and thallium (Tl) were detected in soil samples collected from schoolyards both prior to Hurricane Katrina and after Hurricane Rita. Approximately 43% (9/21) of schoolyard soils collected prior to Hurricane Katrina contained Pb concentrations greater than 400mgkg(-1), and samples from four schoolyards collected after Hurricane Rita contained detectable Pb concentrations, with two exceeding 1700mgkg(-1). Thallium concentrations exceeded USEPA-RSL in samples collected from five schoolyards after Hurricane Rita. Based upon these findings and the known increased susceptibility of children to the effects of Pb exposure, a more extensive assessment of the soils in schoolyards, public parks and other residential areas of New Orleans for metal contaminants is warranted. 2010 Elsevier Ltd. All rights reserved.

Fungi, aflatoxins, and cyclopiazonic acid associated with peanut retailing in Botswana.

PubMed

Mphande, Fingani A; Siame, Bupe A; Taylor, Joanne E

2004-01-01

Peanuts are important food commodities, but they are susceptible to fungal infestation and mycotoxin contamination. Raw peanuts were purchased from retail outlets in Botswana and examined for fungi and mycotoxin (aflatoxins and cyclopiazonic acid) contamination. Zygomycetes were the most common fungi isolated; they accounted for 41% of all the isolates and were found on 98% of the peanut samples. Among the Zygomycetes, Absidia corymbifera and Rhizopus stolonifer were the most common. Aspergillus spp. accounted for 35% of all the isolates, with Aspergillus niger being the most prevalent (20.4%). Aspergillus flavus/parasiticus were also present and accounted for 8.5% of all the isolates, with A. flavus accounting for the majority of the A. flavus/parasiticus identified. Of the 32 isolates of A. flavus screened for mycotoxin production, 11 did not produce detectable aflatoxins, 8 produced only aflatoxins B1 and B2, and 13 produced all four aflatoxins (B1, B2, G1, and G2) in varying amounts. Only 6 of the A. flavus isolates produced cyclopiazonic acid at concentrations ranging from 1 to 55 microg/kg. The one A. parasiticus isolate screened also produced all the four aflatoxins (1,200 microg/kg) but did not produce cyclopiazonic acid. When the raw peanut samples (n = 120) were analyzed for total aflatoxins, 78% contained aflatoxins at concentrations ranging from 12 to 329 microg/kg. Many of the samples (49%) contained total aflatoxins at concentrations above the 20 microg/kg limit set by the World Health Organization. Only 21% (n = 83) of the samples contained cyclopiazonic acid with concentrations ranging from 1 to 10 microg/kg. The results show that mycotoxins and toxigenic fungi are common contaminants of peanuts sold at retail in Botswana.

Plasma capric acid concentrations in healthy subjects determined by high-performance liquid chromatography.

PubMed

Shrestha, Rojeet; Hui, Shu-Ping; Imai, Hiromitsu; Hashimoto, Satoru; Uemura, Naoto; Takeda, Seiji; Fuda, Hirotoshi; Suzuki, Akira; Yamaguchi, Satoshi; Hirano, Ken-Ichi; Chiba, Hitoshi

2015-09-01

Capric acid (FA10:0, decanoic acid) is a medium-chain fatty acid abundant in tropical oils such as coconut oil, whereas small amounts are present in milk of goat, cow, and human. Orally ingested FA10:0 is transported to the liver and quickly burnt within it. Only few reports are available for FA10:0 concentrations in human plasma. Fasting (n = 5, male/female = 3/2, age 31 ± 9.3 years old) and non-fasting (n = 106, male/female = 44/62, age 21.9 ± 3.2 years old) blood samples were collected from apparently healthy Japanese volunteers. The total FA10:0 in the plasma were measured by high-performance liquid chromatography after derivatization with 2-nitrophenylhydrazine followed by UV detection. Inter and intra-assay coefficient of variation of FA10:0 assay at three different concentrations ranged in 1.7-3.9 and 1.3-5.4%, respectively, with an analytical recovery of 95.2-104.0%. FA10:0 concentration was below detection limit (0.1 µmol/L) in each fasting human plasma. FA10:0 was not detected in 50 (47.2%) of 106 non-fasting blood samples, while 29 (27.4%) plasma samples contained FA10:0 less than or equal to 0.5 µmol/L (0.4 ± 0.1), and 27 (25.5%) contained it at more than 0.5 µmol/L (0.9 ± 0.3). A half of the non-fasting plasma samples contained detectable FA10:0. This simple, precise, and accurate high-performance liquid chromatography method might be useful for monitoring plasma FA10:0 during medium-chain triglycerides therapy. © The Author(s) 2015.

Influence of photon beam energy on the dose enhancement factor caused by gold and silver nanoparticles: An experimental approach

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

Guidelli, Eder José, E-mail: ederguidelli@pg.ffclrp.usp.br; Baffa, Oswaldo

Purpose: Noble metal nanoparticles have found several medical applications in the areas of radiation detection; x-ray contrast agents and cancer radiation therapy. Based on computational methods, many papers have reported the nanoparticle effect on the dose deposition in the surrounding medium. Here the authors report experimental results on how silver and gold nanoparticles affect the dose deposition in alanine dosimeters containing several concentrations of silver and gold nanoparticles, for five different beam energies, using electron spin resonance spectroscopy (ESR). Methods: The authors produced alanine dosimeters containing several mass percentage of silver and gold nanoparticles. Nanoparticle sizes were measured by dynamicmore » light scattering and by transmission electron microscopy. The authors determined the dose enhancement factor (DEF) theoretically, using a widely accepted method, and experimentally, using ESR spectroscopy. Results: The DEF is governed by nanoparticle concentration, size, and position in the alanine matrix. Samples containing gold nanoparticles afford a DEF higher than 1.0, because gold nanoparticle size is homogeneous for all gold concentrations utilized. For samples containing silver particles, the silver mass percentage governs the nanoparticles size, which, in turns, modifies nanoparticle position in the alanine dosimeters. In this sense, DEF decreases for dosimeters containing large and segregated particles. The influence of nanoparticle size-position is more noticeable for dosimeters irradiated with higher beam energies, and dosimeters containing large and segregated particles become less sensitive than pure alanine (DEF < 1). Conclusions: ESR dosimetry gives the DEF in a medium containing metal nanoparticles, although particle concentration, size, and position are closely related in the system. Because this is also the case as in many real systems of materials containing inorganic nanoparticles, ESR is a valuable tool for investigating DEF. Moreover, these results alert to the importance of controlling the size-position of nanoparticles to enhance DEF.« less

Nicotinamide Riboside Is a Major NAD+ Precursor Vitamin in Cow Milk.

PubMed

Trammell, Samuel Aj; Yu, Liping; Redpath, Philip; Migaud, Marie E; Brenner, Charles

2016-05-01

Nicotinamide riboside (NR) is a recently discovered NAD(+) precursor vitamin with a unique biosynthetic pathway. Although the presence of NR in cow milk has been known for more than a decade, the concentration of NR with respect to the other NAD(+) precursors was unknown. We aimed to determine NAD(+) precursor vitamin concentration in raw samples of milk from individual cows and from commercially available cow milk. LC tandem mass spectrometry and isotope dilution technologies were used to quantify NAD(+) precursor vitamin concentration and to measure NR stability in raw and commercial milk. Nuclear magnetic resonance (NMR) spectroscopy was used to test for NR binding to substances in milk. Cow milk typically contained ∼12 μmol NAD(+) precursor vitamins/L, of which 60% was present as nicotinamide and 40% was present as NR. Nicotinic acid and other NAD(+) metabolites were below the limits of detection. Milk from samples testing positive for Staphylococcus aureus contained lower concentrations of NR (Spearman ρ = -0.58, P = 0.014), and NR was degraded by S. aureus Conventional milk contained more NR than milk sold as organic. Nonetheless, NR was stable in organic milk and exhibited an NMR spectrum consistent with association with a protein fraction in skim milk. NR is a major NAD(+) precursor vitamin in cow milk. Control of S. aureus may be important to preserve the NAD(+) precursor vitamin concentration of milk. © 2016 American Society for Nutrition.

Quality of water in the Trinity and Edwards aquifers, south-central Texas, 1996-98

USGS Publications Warehouse

Fahlquist, Lynne; Ardis, Ann F.

2004-01-01

During 1996–98, the U.S. Geological Survey studied surface- and ground-water quality in south-central Texas. The ground-water components included the upper and middle zones (undifferentiated) of the Trinity aquifer in the Hill Country and the unconfined part (recharge zone) and confined part (artesian zone) of the Edwards aquifer in the Balcones fault zone of the San Antonio region. The study was supplemented by information compiled from four ground-water-quality studies done during 1996–98.Trinity aquifer waters are more mineralized and contain larger dissolved solids, sulfate, and chloride concentrations compared to Edwards aquifer waters. Greater variability in water chemistry in the Trinity aquifer likely reflects the more variable lithology of the host rock. Trace elements were widely detected, mostly at small concentrations. Median total nitrogen was larger in the Edwards aquifer than in the Trinity aquifer. Ammonia nitrogen was detected more frequently and at larger concentrations in the Trinity aquifer than in the Edwards aquifer. Although some nitrate nitrogen concentrations in the Edwards aquifer exceeded a U.S. Geological Survey national background threshold concentration, no concentrations exceeded the U.S. Environmental Protection Agency public drinking-water standard.Synthetic organic compounds, such as pesticides and volatile organic compounds, were detected in the Edwards aquifer and less frequently in the Trinity aquifer, mostly at very small concentrations (less than 1 microgram per liter). These compounds were detected most frequently in urban unconfined Edwards aquifer samples. Atrazine and its breakdown product deethylatrazine were the most frequently detected pesticides, and trihalomethanes were the most frequently detected volatile organic compounds. Widespread detections of these compounds, although at small concentrations, indicate that anthropogenic activities affect ground-water quality.Radon gas was detected throughout the Trinity aquifer but not throughout the Edwards aquifer. Fourteen samples from the Trinity aquifer and 10 samples from the Edwards aquifer exceeded a proposed U.S. Environmental Protection Agency public drinking-water standard. Sources of radon in the study area might be granitic sediments underlying the Trinity aquifer and igneous intrusions in and below the Edwards aquifer.The presence of tritium in nearly all Edwards aquifer samples indicates that some component of sampled water is young (less than about 50 years), even for long flow paths in the confined zone. About one-half of the Trinity aquifer samples contained tritium, indicating that only part of the aquifer contains young water.Hydrogen and oxygen isotopes of water provide indicators of recharge sources to the Trinity and Edwards aquifers. Most ground-water samples have a meteorological isotopic signature indicating recharge as direct infiltration of water with little residence time on the land surface. Isotopic data from some samples collected from the unconfined Edwards aquifer indicate the water has undergone evaporation. At the time that ground-water samples were collected (during a drought), nearby streams were the likely sources of recharge to these wells.

Magnetic hyperthermia study in water based magnetic fluids containing TMAOH coated Fe3O4 using infrared thermography

NASA Astrophysics Data System (ADS)

Lahiri, B. B.; Ranoo, Surojit; Philip, John

2017-01-01

We study the alternating magnetic field induced heating of a water based ferrofluid containing tetramethyl ammonium hydroxide coated iron oxide nanoparticles using infrared thermography and compare the results obtained from the conventional fiber optic temperature sensor. Experiments are performed on ferrofluid samples of five different concentrations and under four different external field amplitudes at a fixed frequency. The temperature rise curves measured using both the infrared thermography and fiber optic sensor are found to be very similar up to a certain time interval, above which deviations are observed, which are attributed to the internal and external convection phenomena. A correction methodology is developed to account for the convection losses. The convection corrected specific absorption rate is found to be in good agreement with the values obtained from the conventional fiber optic temperature sensor, within a maximum error of ±3.4%. The highest specific absorption rate obtained in the present study is 135.98 (±4.6) W/gFe for a sample concentration of 3 wt.%, at an external field amplitude and a frequency of 63.0 kA m-1 and 126 kHz, respectively. The specific absorption rate is found to decrease with increasing sample concentration, due to the enhancement of dipolar interaction with increasing sample concentration due to agglomeration. This study validates the efficacy and universal applicability of IRT as an alternate, real time, non-contact and wide area temperature measurement methodology for magnetic fluid hyperthermia experiments without any sample contamination.

Pesticide contamination of endangered gray bats and their food base in Boone County, Missouri, 1982

USGS Publications Warehouse

Clawson, R.L.; Clark, D.R.

1989-01-01

Gray bat guano from Devil's Icebox and Hunters Caves contained dieldrin at levels previously associated with gray bat mortality. Two of four gray bats found dead in Holton Cave had lethal brain concentrations of dieldrin. Twenty-five of 28 (86%) insect samples from bat foraging areas contained measurable dieldrin, heptachlor epoxide or both. Beetle samples were most heavily contaminated containing up to 2.2 ppm and 1.1 ppm heptachlor epoxide. The addition of Holton Cave brings to five the number of Missouri caves where gray bats have died of food chain pesticide poisoning.

Water-quality data for Walnut Canyon and Wupatki National Monuments, Arizona, 2001-02

USGS Publications Warehouse

Thomas, Blakemore E.

2003-01-01

Water-quality data are provided for four sites in Walnut Canyon and Wupatki National Monuments in north-central Arizona. These data describe the current water quality and provide baseline water-quality information for monitoring future trends. Water samples were collected from a ground-water seep and well in Walnut Canyon and from a spring and a river in Wupatki during September 2001 to September 2002. Water from the four sites is from four different sources. In Walnut Canyon, Cherry Canyon seep is in a shallow local aquifer, and the Little Colorado River contains ground-water discharge from several aquifers and runoff from a 22,000 square-mile drainage area. Concentrations of dissolved solids were similar within the two monuments; the range for water samples from Walnut Canyon was 203 to 248 milligrams per liter, and the range for water samples from Wupatki was 503 to 614 milligrams per liter. Concentrations of trace elements were generally low in water samples from the three ground-water sites--Cherry Canyon seep, Walnut Canyon headquarters well, and Heiser Spring. The water sample collected from the Little Colorado River, however, had high concentrations of aluminum (4,020 micrograms per liter), antimony (54 micrograms per liter), arsenic (14.3 micrograms per liter), and iron (749 micrograms per liter) relative to U.S. Environmental Protection Agency Primary and Secondary Maximum Contaminant Levels. Concentrations of nitrate (as nitrogen) in water samples from the four sites were generally low (0.11 to 1.8 milligrams per liter) and are within the upper 25 percent of nitrate concentrations measured in the regional aquifer near Flagstaff in 1996 and 1997. Water samples from Cherry Canyon seep, Heiser Spring, and the Little Colorado River contained total coliform bacteria. Fecal coliform and Escherichia coli bacteria were found in water samples from Cherry Canyon seep and the Little Colorado River.

HNU-HANBY PCP IMMUNOASSAY TEST KIT - INNOVATIVE TECHNOLOGY EVALUATION REPORT

EPA Science Inventory

The HNU-Hanby pentachlorophenol (PCP) test kit rapidly analyzes for PCP in soil samples. The test kit can only detect those PCP carriers that contain aromatic compounds. The test kit estimates PCP concentrations in soil samples indirectly by measuring petroleum hydrocarbon carrie...

PRESERVATION OF SULFIDIC WATERS CONTAINING DISSOLVED AS (III)

EPA Science Inventory

Field samples for arsenic analyses are commonly preserved by acidification with hydrochloric or nitric acid. In some suboxic samples, appreciable concentrations of H2S and HS- are observed due to the microbial respiration of sulfate-reducing bacteria. If both As(III) and sulfid...

Influence of Chloride Ions as Contaminants on the Corrosion Behavior of Alloy 718 in Pool Water of Nuclear Power Plants

NASA Astrophysics Data System (ADS)

Hugues, Jonathan; Andrieu, Eric; Blanc, Christine; Cloué, Jean-Marc

The electrochemical behavior of alloy 718 in a chloride-containing boric acid solution was studied to determine the influence of chloride ions as contaminants of pool water of nuclear power plants on the corrosion behavior of the alloy. Experiments were performed at 20°C and 60°C with chloride concentrations from 1.5 to 15 000 ppm, using stationary measurements i.e. OCP versus time measurements and plotting of current-potential curves. After the electrochemical tests, the samples were observed using optical microscopy. Immersion tests in chloride-containing boric acid solutions were also carried out: samples were immersed for a time as long as 17 weeks at open circuit potential and their residual mechanical properties were measured. Results showed that, whatever the chloride concentration, there was no corrosion for samples immersed at open circuit potential. However, when the samples were polarized at high potentials, intergranular corrosion might be observed in occluded zones.

Quantifying Sulfur-Containing Compounds Over the Santa Barbara Channel

NASA Astrophysics Data System (ADS)

Black, J.; Hughes, S.; Blake, D. R.

2016-12-01

Carbonyl sulfide (OCS) is emitted to the atmosphere through the outgassing of ocean surface waters. OCS is also the primary source of sulfur-containing compounds in the stratosphere and contributes to the formation of the stratospheric sulfate layer. During the 2016 Student Airborne Research Program (SARP), whole air samples were collected on the NASA DC-8 aircraft over the Santa Barbara Channel. Five additional surface samples were taken at various locations along the Santa Barbara Channel. The samples were analyzed using gas chromatography in the Rowland-Blake lab at UC Irvine, and compounds such as OCS, dimethyl sulfide (DMS), carbon disulfide (CS2), bromoform (CHBr3), and methyl iodide (CH3I) associated with ocean emissions and stratospheric aerosols were analyzed. These marine sourced compounds, excluding OCS, showed expected trends of dilution with increasing altitude. The surface samples from the Santa Barbara Channel all exhibited elevated concentrations of OCS in comparison to samples taken from the aircraft, with an average of 666 ± 12 pptv, whereas the average background concentration of OCS was 587 ± 19 pptv. SARP flights from 2009-2015 over the Santa Barbara Channel saw an average OCS concentration of 548 ± 26 pptv. Elevated levels of OCS have never been detected from the aircraft during SARP flights, indicating that OCS emissions must be measured using surface sampling if emission estimates from the ocean are to be evaluated.

Profiling oil sands mixtures from industrial developments and natural groundwaters for source identification.

PubMed

Frank, Richard A; Roy, James W; Bickerton, Greg; Rowland, Steve J; Headley, John V; Scarlett, Alan G; West, Charles E; Peru, Kerry M; Parrott, Joanne L; Conly, F Malcolm; Hewitt, L Mark

2014-01-01

The objective of this study was to identify chemical components that could distinguish chemical mixtures in oil sands process-affected water (OSPW) that had potentially migrated to groundwater in the oil sands development area of northern Alberta, Canada. In the first part of the study, OSPW samples from two different tailings ponds and a broad range of natural groundwater samples were assessed with historically employed techniques as Level-1 analyses, including geochemistry, total concentrations of naphthenic acids (NAs) and synchronous fluorescence spectroscopy (SFS). While these analyses did not allow for reliable source differentiation, they did identify samples containing significant concentrations of oil sands acid-extractable organics (AEOs). In applying Level-2 profiling analyses using electrospray ionization high resolution mass spectrometry (ESI-HRMS) and comprehensive multidimensional gas chromatography time-of-flight mass spectrometry (GC × GC-TOF/MS) to samples containing appreciable AEO concentrations, differentiation of natural from OSPW sources was apparent through measurements of O2:O4 ion class ratios (ESI-HRMS) and diagnostic ions for two families of suspected monoaromatic acids (GC × GC-TOF/MS). The resemblance between the AEO profiles from OSPW and from 6 groundwater samples adjacent to two tailings ponds implies a common source, supporting the use of these complimentary analyses for source identification. These samples included two of upward flowing groundwater collected <1 m beneath the Athabasca River, suggesting OSPW-affected groundwater is reaching the river system.

Darunavir concentrations in cerebrospinal fluid and blood in HIV-1-infected individuals.

PubMed

Yilmaz, Aylin; Izadkhashti, Arash; Price, Richard W; Mallon, Patrick W; De Meulder, Marc; Timmerman, Philip; Gisslén, Magnus

2009-04-01

Darunavir is the most recently licensed protease inhibitor currently used in treatment-experienced HIV-infected individuals. Our objective was to determine darunavir concentrations in cerebrospinal fluid (CSF) and plasma in subjects receiving antiretroviral treatment regimens containing ritonavir-boosted darunavir. Darunavir concentrations were determined by liquid chromatography tandem mass spectrometry in 14 paired CSF and plasma samples from eight HIV-1-infected individuals. The lower limit of quantification was 5.0 ng/ml. All of the 14 CSF samples had detectable darunavir concentrations with a median darunavir concentration of 34.2 ng/ml (range 15.9-212.0 ng/ml). The median (range) plasma darunavir concentration was 3930 (1800-12900) ng/ml. All CSF samples had detectable darunavir concentrations. Most of them exceeded or were in the same range as levels needed to inhibit replication of wild type virus, making it probable that darunavir, at least to some extent, contributes to the suppression of HIV replication in the central nervous system.

Turbidimetric Estimation of Alcohol Concentration in Aqueous-Alcohol Mixtures

ERIC Educational Resources Information Center

Swinehart, William E.; Zimmerman, Bonnie L.; Powell, Kinsey; Moore, Stephen D.; Iordanov, Tzvetelin D.

2014-01-01

A concept of the turbidimetric method for determining the concentration of ethanol in water-ethanol mixtures is described. A closed sample cell containing the analyte was heated to achieve vapor saturation and subsequent condensation. As the condensation occurred, the decrease in percentage transmittance with time due to light scattering was…

Mercury methylation influenced by areas of past mercury mining in the Terlingua district, Southwest Texas, USA

USGS Publications Warehouse

Gray, J.E.; Hines, M.E.; Biester, H.

2006-01-01

Speciation and microbial transformation of Hg was studied in mine waste from abandoned Hg mines in SW Texas to evaluate the potential for methyl-Hg production and degradation in mine wastes. In mine waste samples, total Hg, ionic Hg2+, Hg0, methyl-Hg, organic C, and total S concentrations were measured, various Hg compounds were identified using thermal desorption pyrolysis, and potential rates of Hg methylation and methyl-Hg demethylation were determined using isotopic-tracer methods. These data are the first reported for Hg mines in this region. Total Hg and methyl-Hg concentrations were also determined in stream sediment collected downstream from two of the mines to evaluate transport of Hg and methylation in surrounding ecosystems. Mine waste contains total Hg and methyl-Hg concentrations as high as 19,000 ??g/g and 1500 ng/g, respectively, which are among the highest concentrations reported at Hg mines worldwide. Pyrolysis analyses show that mine waste contains variable amounts of cinnabar, metacinnabar, Hg0, and Hg sorbed onto particles. Methyl-Hg concentrations in mine waste correlate positively with ionic Hg2+, organic C, and total S, which are geochemical parameters that influence processes of Hg cycling and methylation. Net methylation rates were as high as 11,000 ng/g/day, indicating significant microbial Hg methylation at some sites, especially in samples collected inside retorts. Microbially-mediated methyl-Hg demethylation was also observed in many samples, but where both methylation and demethylation were found, the potential rate of methylation was faster. Total Hg concentrations in stream sediment samples were generally below the probable effect concentration of 1.06 ??g/g, the Hg concentration above which harmful effects are likely to be observed in sediment dwelling organisms; whereas total Hg concentrations in mine waste samples were found to exceed this concentration, although this is a sediment quality guideline and is not directly applicable to mine waste. Although total Hg and methyl-Hg concentrations are locally high in some mine waste samples, little Hg appears to be exported from these Hg mines in stream sediment primarily due to the arid climate and lack of precipitation and mine runoff in this region. ?? 2006 Elsevier Ltd. All rights reserved.

Effects of recharge and discharge on delta2H and delta18O composition and chloride concentration of high arsenic/fluoride groundwater from the Datong Basin, northern China.

PubMed

Xie, Xianjun; Wang, Yanxin; Su, Chunli; Duan, Mengyu

2013-02-01

To better understand the effects of recharge and discharge on the hydrogeochemistry of high levels of arsenic (As) and fluoride (F) in groundwater, environmental isotopic composition (delta2H and delta18O) and chloride (Cl) concentrations were analyzed in 29 groundwater samples collected from the Datong Basin. High arsenic groundwater samples (As > 50 micog/L) were found to be enriched in lighter isotopic composition that ranged from -92 to -78 per thousand for deuterium (delta2H) and from -12.5 to -9.9 per thousand for oxygen-18 (delta18O). High F-containing groundwater (F > 1 mg/L) was relatively enriched in heavier isotopic composition and varied from -90 to -57 per thousand and from -12.2 to -6.7 per thousand for delta2H and delta18O, respectively. High chloride concentrations and delta18O values were primarily measured in groundwater samples from the northern and southwestern portions of the study area, indicating the effect of evaporation on groundwater. The observation of relatively homogenized and low delta18O values and chloride concentrations in groundwater samples from central part of the Datong Basin might be a result of fast recharge by irrigation returns, which suggests that irrigation using arsenic-contaminated groundwater affected the occurrence of high arsenic-containing groundwater in the basin.

Presence of Tungsten-Containing Fibers in Tungsten Refining and Manufacturing Processes

PubMed Central

Mckernan, John L.; Toraason, Mark A.; Fernback, Joseph E.; Petersen, Martin R.

2009-01-01

In tungsten refining and manufacturing processes, a series of tungsten oxides are typically formed as intermediates in the production of tungsten powder. The present study was conducted to characterize airborne tungsten-containing fiber dimensions, elemental composition and concentrations in the US tungsten refining and manufacturing industry. During the course of normal employee work activities, seven personal breathing zone and 62 area air samples were collected and analyzed using National Institute for Occupational Safety and Health (NIOSH) fiber sampling and counting methods to determine dimensions, composition and airborne concentrations of fibers. Mixed models were used to identify relationships between potential determinants and airborne fiber concentrations. Results from transmission electron microscopy analyses indicated that airborne fibers with length >0.5 μm, diameter >0.01 μm and aspect ratios ≥3:1 were present on 35 of the 69 air samples collected. Overall, the airborne fibers detected had a geometric mean length ≈3 μm and diameter ≈0.3 μm. Ninety-seven percent of the airborne fibers identified were in the thoracic fraction (i.e. aerodynamic diameter ≤ 10 μm). Energy dispersive X-ray spectrometry results indicated that airborne fibers prior to the carburization process consisted primarily of tungsten and oxygen, with other elements being detected in trace quantities. Based on NIOSH fiber counting ‘B’ rules (length > 5 μm, diameter < 3 μm and aspect ratio ≥ 5:1), airborne fiber concentrations ranged from below the limit of detection to 0.085 fibers cm−3, with calcining being associated with the highest airborne concentrations. The mixed model procedure indicated that process temperature had a marginally significant relationship to airborne fiber concentration. This finding was expected since heated processes such as calcining created the highest airborne fiber concentrations. The finding of airborne tungsten-containing fibers in this occupational setting needs to be confirmed in similar settings and demonstrates the need to obtain information on the durability and associated health effects of these fibers. PMID:19126624

Systems and methods for the detection of low-level harmful substances in a large volume of fluid

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

Carpenter, Michael V.; Roybal, Lyle G.; Lindquist, Alan

A method and device for the detection of low-level harmful substances in a large volume of fluid comprising using a concentrator system to produce a retentate and analyzing the retentate for the presence of at least one harmful substance. The concentrator system performs a method comprising pumping at least 10 liters of fluid from a sample source through a filter. While pumping, the concentrator system diverts retentate from the filter into a container. The concentrator system also recirculates at least part of the retentate in the container again through the filter. The concentrator system controls the speed of the pumpmore » with a control system thereby maintaining a fluid pressure less than 25 psi during the pumping of the fluid; monitors the quantity of retentate within the container with a control system, and maintains a reduced volume level of retentate and a target volume of retentate.« less

In Vitro Studies Evaluating Leaching of Mercury from Mine Waste Calcine Using Simulated Human Body Fluids

PubMed Central

2010-01-01

In vitro bioaccessibility (IVBA) studies were carried out on samples of mercury (Hg) mine-waste calcine (roasted Hg ore) by leaching with simulated human body fluids. The objective was to estimate potential human exposure to Hg due to inhalation of airborne calcine particulates and hand-to-mouth ingestion of Hg-bearing calcines. Mine waste calcines collected from Hg mines at Almadén, Spain, and Terlingua, Texas, contain Hg sulfide, elemental Hg, and soluble Hg compounds, which constitute primary ore or compounds formed during Hg retorting. Elevated leachate Hg concentrations were found during calcine leaching using a simulated gastric fluid (as much as 6200 μg of Hg leached/g sample). Elevated Hg concentrations were also found in calcine leachates using a simulated lung fluid (as much as 9200 μg of Hg leached/g), serum-based fluid (as much as 1600 μg of Hg leached/g), and water of pH 5 (as much as 880 μg of Hg leached/g). The leaching capacity of Hg is controlled by calcine mineralogy; thus, calcines containing soluble Hg compounds contain higher leachate Hg concentrations. Results indicate that ingestion or inhalation of Hg mine-waste calcine may lead to increased Hg concentrations in the human body, especially through the ingestion pathway. PMID:20491469

In vitro studies evaluating leaching of mercury from mine waste calcine using simulated human body fluids.

PubMed

Gray, John E; Plumlee, Geoffrey S; Morman, Suzette A; Higueras, Pablo L; Crock, James G; Lowers, Heather A; Witten, Mark L

2010-06-15

In vitro bioaccessibility (IVBA) studies were carried out on samples of mercury (Hg) mine-waste calcine (roasted Hg ore) by leaching with simulated human body fluids. The objective was to estimate potential human exposure to Hg due to inhalation of airborne calcine particulates and hand-to-mouth ingestion of Hg-bearing calcines. Mine waste calcines collected from Hg mines at Almaden, Spain, and Terlingua, Texas, contain Hg sulfide, elemental Hg, and soluble Hg compounds, which constitute primary ore or compounds formed during Hg retorting. Elevated leachate Hg concentrations were found during calcine leaching using a simulated gastric fluid (as much as 6200 microg of Hg leached/g sample). Elevated Hg concentrations were also found in calcine leachates using a simulated lung fluid (as much as 9200 microg of Hg leached/g), serum-based fluid (as much as 1600 microg of Hg leached/g), and water of pH 5 (as much as 880 microg of Hg leached/g). The leaching capacity of Hg is controlled by calcine mineralogy; thus, calcines containing soluble Hg compounds contain higher leachate Hg concentrations. Results indicate that ingestion or inhalation of Hg mine-waste calcine may lead to increased Hg concentrations in the human body, especially through the ingestion pathway.

In vitro studies evaluating leaching of mercury from mine waste calcine using simulated human body fluids

USGS Publications Warehouse

Gray, John E.; Plumlee, Geoffrey S.; Morman, Suzette A.; Higueras, Pablo L.; Crock, James G.; Lowers, Heather A.; Witten, Mark L.

2010-01-01

In vitro bioaccessibility (IVBA) studies were carried out on samples of mercury (Hg) mine-waste calcine (roasted Hg ore) by leaching with simulated human body fluids. The objective was to estimate potential human exposure to Hg due to inhalation of airborne calcine particulates and hand-to-mouth ingestion of Hg-bearing calcines. Mine waste calcines collected from Hg mines at Almadén, Spain, and Terlingua, Texas, contain Hg sulfide, elemental Hg, and soluble Hg compounds, which constitute primary ore or compounds formed during Hg retorting. Elevated leachate Hg concentrations were found during calcine leaching using a simulated gastric fluid (as much as 6200 μg of Hg leached/g sample). Elevated Hg concentrations were also found in calcine leachates using a simulated lung fluid (as much as 9200 μg of Hg leached/g), serum-based fluid (as much as 1600 μg of Hg leached/g), and water of pH 5 (as much as 880 μg of Hg leached/g). The leaching capacity of Hg is controlled by calcine mineralogy; thus, calcines containing soluble Hg compounds contain higher leachate Hg concentrations. Results indicate that ingestion or inhalation of Hg mine-waste calcine may lead to increased Hg concentrations in the human body, especially through the ingestion pathway.

Comparison of nitrate, pesticides, and volatile organic compounds in samples from monitoring and public-supply wells, Kirkwood-Cohansey aquifer system, southern New Jersey

USGS Publications Warehouse

Stackelberg, Paul E.; Kauffman, L.J.; Baehr, A.L.; Ayers, M.A.

2000-01-01

The number and total concentration of volatile organic compounds (VOCs) per sample were significantly greater in water from public-supply wells than in water from shallow and moderate-depth monitoring wells in the surficial Kirkwood-Cohansey aquifer system in the Glassboro area of southern New Jersey. In contrast, concentrations of nitrate (as nitrogen) and the number and total concentration of pesticides per sample were statistically similar in samples from shallow and moderate-depth monitoring wells and those from public-supply wells. VOCs in ground water typically are derived from point sources, which commonly exist in urban areas and which result in spatially variable contaminant concentrations near the water table. Because larger volumes of water are withdrawn from public-supply wells than from monitoring wells, their contributing areas are larger and, therefore, they are more likely to intercept water flowing from VOC point sources. Additionally, public-supply wells intercept flow paths that span a large temporal interval. Public-supply wells in the Glassboro study area withdraw water flowing along short paths, which contains VOCs that recently entered the aquifer system, and water flowing along relatively long paths, which contains VOCs that originated from the degradation of parent compounds or that are associated with past land uses. Because the volume of water withdrawn from monitoring wells is small and because shallow monitoring wells are screened near the water table, they generally intercept only relatively short flow paths. Therefore, samples from these wells represent relatively recent, discrete time intervals and contain both fewer VOCs and a lower total VOC concentration than samples from public-supply wells. Nitrate and pesticides in ground water typically are derived from nonpoint sources, which commonly are found in both agricultural and urban areas and typically result in lowlevel, relatively uniform concentrations near the water table. Because nonpoint sources are diffuse and because processes such as degradation or sorption/dispersion do not occur at rates sufficient to prevent detection of these constituents in parts of the aquifer used for domestic and public supply in the study area, concentrations of nitrate and pesticides and numbers of pesticide compounds are likely to be similar in samples from shallow monitoring wells and samples from public-supply wells. Results of a comparison of (1) the general characteristics of, and water-quality data from, public-supply wells in the Glassboro study area to available data from public-supply wells screened in the Kirkwood-Cohansey aquifer system outside the study area, and (2) land-use settings, soil characteristics, and aquifer properties in and outside the study area indicate that the findings of this study likely are applicable to the entire extent of the Kirkwood- Cohansey aquifer system in southern New Jersey.

[Nitrate concentrations in tap water in Spain].

PubMed

Vitoria, Isidro; Maraver, Francisco; Sánchez-Valverde, Félix; Armijo, Francisco

2015-01-01

To determine nitrate concentrations in drinking water in a sample of Spanish cities. We used ion chromatography to analyze the nitrate concentrations of public drinking water in 108 Spanish municipalities with more than 50,000 inhabitants (supplying 21,290,707 potential individuals). The samples were collected between January and April 2012. The total number of samples tested was 324. The median nitrate concentration was 3.47 mg/L (range: 0.38-66.76; interquartile range: 4.51). The water from 94% of the municipalities contained less than 15 mg/L. The concentration was higher than 25mg/L in only 3 municipalities and was greater than 50mg/L in one. Nitrate levels in most public drinking water supplies in municipalities inhabited by almost half of the Spanish population are below 15 mg/L. Copyright © 2014 SESPAS. Published by Elsevier Espana. All rights reserved.

“Nanofiltration” Enabled by Super-Absorbent Polymer Beads for Concentrating Microorganisms in Water Samples

NASA Astrophysics Data System (ADS)

Xie, Xing; Bahnemann, Janina; Wang, Siwen; Yang, Yang; Hoffmann, Michael R.

2016-02-01

Detection and quantification of pathogens in water is critical for the protection of human health and for drinking water safety and security. When the pathogen concentrations are low, large sample volumes (several liters) are needed to achieve reliable quantitative results. However, most microbial identification methods utilize relatively small sample volumes. As a consequence, a concentration step is often required to detect pathogens in natural waters. Herein, we introduce a novel water sample concentration method based on superabsorbent polymer (SAP) beads. When SAP beads swell with water, small molecules can be sorbed within the beads, but larger particles are excluded and, thus, concentrated in the residual non-sorbed water. To illustrate this approach, millimeter-sized poly(acrylamide-co-itaconic acid) (P(AM-co-IA)) beads are synthesized and successfully applied to concentrate water samples containing two model microorganisms: Escherichia coli and bacteriophage MS2. Experimental results indicate that the size of the water channel within water swollen P(AM-co-IA) hydrogel beads is on the order of several nanometers. The millimeter size coupled with a negative surface charge of the beads are shown to be critical in order to achieve high levels of concentration. This new concentration procedure is very fast, effective, scalable, and low-cost with no need for complex instrumentation.

"Nanofiltration" Enabled by Super-Absorbent Polymer Beads for Concentrating Microorganisms in Water Samples.

PubMed

Xie, Xing; Bahnemann, Janina; Wang, Siwen; Yang, Yang; Hoffmann, Michael R

2016-02-15

Detection and quantification of pathogens in water is critical for the protection of human health and for drinking water safety and security. When the pathogen concentrations are low, large sample volumes (several liters) are needed to achieve reliable quantitative results. However, most microbial identification methods utilize relatively small sample volumes. As a consequence, a concentration step is often required to detect pathogens in natural waters. Herein, we introduce a novel water sample concentration method based on superabsorbent polymer (SAP) beads. When SAP beads swell with water, small molecules can be sorbed within the beads, but larger particles are excluded and, thus, concentrated in the residual non-sorbed water. To illustrate this approach, millimeter-sized poly(acrylamide-co-itaconic acid) (P(AM-co-IA)) beads are synthesized and successfully applied to concentrate water samples containing two model microorganisms: Escherichia coli and bacteriophage MS2. Experimental results indicate that the size of the water channel within water swollen P(AM-co-IA) hydrogel beads is on the order of several nanometers. The millimeter size coupled with a negative surface charge of the beads are shown to be critical in order to achieve high levels of concentration. This new concentration procedure is very fast, effective, scalable, and low-cost with no need for complex instrumentation.

“Nanofiltration” Enabled by Super-Absorbent Polymer Beads for Concentrating Microorganisms in Water Samples

PubMed Central

Xie, Xing; Bahnemann, Janina; Wang, Siwen; Yang, Yang; Hoffmann, Michael R.

2016-01-01

Detection and quantification of pathogens in water is critical for the protection of human health and for drinking water safety and security. When the pathogen concentrations are low, large sample volumes (several liters) are needed to achieve reliable quantitative results. However, most microbial identification methods utilize relatively small sample volumes. As a consequence, a concentration step is often required to detect pathogens in natural waters. Herein, we introduce a novel water sample concentration method based on superabsorbent polymer (SAP) beads. When SAP beads swell with water, small molecules can be sorbed within the beads, but larger particles are excluded and, thus, concentrated in the residual non-sorbed water. To illustrate this approach, millimeter-sized poly(acrylamide-co-itaconic acid) (P(AM-co-IA)) beads are synthesized and successfully applied to concentrate water samples containing two model microorganisms: Escherichia coli and bacteriophage MS2. Experimental results indicate that the size of the water channel within water swollen P(AM-co-IA) hydrogel beads is on the order of several nanometers. The millimeter size coupled with a negative surface charge of the beads are shown to be critical in order to achieve high levels of concentration. This new concentration procedure is very fast, effective, scalable, and low-cost with no need for complex instrumentation. PMID:26876979

Bisphenol A (BPA) in the serum of pet dogs following short-term consumption of canned dog food and potential health consequences of exposure to BPA.

PubMed

Koestel, Zoe L; Backus, Robert C; Tsuruta, Kaoru; Spollen, William G; Johnson, Sarah A; Javurek, Angela B; Ellersieck, Mark R; Wiedmeyer, Charles E; Kannan, Kurunthachalam; Xue, Jingchuan; Bivens, Nathan J; Givan, Scott A; Rosenfeld, Cheryl S

2017-02-01

Bisphenol A (BPA) is a widely present endocrine disruptor chemical found in many household items. Moreover, this chemical can bioaccumulate in various terrestrial and aquatic sources; thereby ensuring continual exposure of animals and humans. For most species, including humans, diet is considered the primary route of exposure. However, there has been little investigation whether commercial-brands of dog foods contain BPA and potential health ramifications of BPA-dietary exposure in dogs. We sought to determine BPA content within dog food, whether short-term consumption of these diets increases serum concentrations of BPA, and potential health consequences, as assessed by potential hematological, serum chemistry, cortisol, DNA methylation, and gut microbiome changes, in dogs associated with short-term dietary exposure to BPA. Fourteen healthy privately-owned dogs were used in this study. Blood and fecal samples were collected prior to dogs being placed for two-weeks on one of two diets (with one considered to be BPA-free), and blood and fecal samples were collected again. Serum/plasma samples were analyzed for chemistry and hematology profiles, cortisol concentrations, 5-methylcytosine in lymphocytes, and total BPA concentrations. Fecal samples were used for microbiome assessments. Both diets contained BPA, and after two-weeks of being on either diet, dogs had a significant increase in circulating BPA concentrations (pre-samples=0.7±0.15ng/mL, post-samples=2.2±0.15ng/mL, p<0.0001). Elevated BPA concentrations positively correlated with increased plasma bicarbonate concentrations and associated with fecal microbiome alterations. Short-term feeding of canned dog food increased circulating BPA concentrations in dogs comparable to amounts detected in humans, and greater BPA concentrations were associated with serum chemistry and microbiome changes. Dogs, who share our internal and external environments with us, are likely excellent indicators of potential human health concerns to BPA and other environmental chemicals. These findings may also have relevance to aquatic and terrestrial wildlife. Copyright © 2016 Elsevier B.V. All rights reserved.

SOLVENT HOLD TANK SAMPLE RESULTS FOR MCU-11-1452, MCU-11-1453, MCU-11-1454, MCU-11-1455, MCU-11-1456 AND MCU-11-1457

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

Peters, T.; Fondeur, F.; Fink, S.

Solvent Hold Tank (SHT) samples are sent to Savannah River National Laboratory (SRNL) to examine solvent composition changes over time. On December 5, 2011, Operations personnel delivered six samples from the SHT (MCU-11-1452 through -1457) for analysis. These samples are intended to verify that the solvent is within the specified composition range. The results from the analyses are presented in this document. Samples were received in p-nut vials containing {approx}10 mL each. Once taken into the Shielded Cells, the samples were combined. Samples were removed for analysis by density, semi-volatile organic analysis (SVOA), high performance liquid chromatography (HPLC), and Fourier-Transformmore » Infra-Red spectroscopy (FTIR). Details for the work are contained in a controlled laboratory notebook. Each of the six p-nut vials contained a single phase, with no apparent solids contamination or cloudiness. Table 1 contains the results of the analyses for the combined samples. A duplicate density measurement of the organic phase gave a result of 0.844 g/mL (1.2% residual standard deviation - RSD). Using the density as a starting point, we know that the Isopar{reg_sign} L should be slightly higher than nominal and the other components should be slightly lower than nominal. The results as a whole are internally consistent. All measurements indicate Isopar{reg_sign} L higher than nominal, and Modifier lower than nominal. The extractant result is higher than expected - given the other results, the extractant concentration should be under nominal values. Using the measured density as well as the Isopar{reg_sign} L and Modifier concentrations from the FTIR results, we calculate an extractant concentration of 6888 mg/L. This value is outside the analytical uncertainty of the reported HPLC value. Given the other results, this most likely indicates that the HPLC extractant result was biased high. When compared to the MCU density target of 0.845 g/mL, there is no need to add an Isopar{reg_sign} L trim. However, it is advisable to add sufficient trioctylamine (TOA) to return the solvent composition to within specifications as that component has declined to about 64% the concentration since the last analysis. The TOA measurement was performed twice, so the result is not an analytical aberration. TOA has not been added to the system since the previous quarterly sample in October 2011. As with the previous solvent sample results, these analyses indicate that the solvent does not require Isopar{reg_sign} L trimming at this time. However, addition of TOA is warranted. These findings indicate that the new protocols for solvent monitoring and control are yielding favorable results. Nevertheless, the deviation in the TOA concentration since the last analysis indicates continued periodic (i.e., quarterly) monitoring is recommended.« less

Analysis of Tank 38H (HTF-38-16-80, 81) and Tank 43H (HTF-43-16-82, 83) Samples for Support of the Enrichment Control and Corrosion Control Programs

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

Hay, M.

2016-10-24

SRNL analyzed samples from Tank 38H and Tank 43H to support ECP and CCP. The total uranium in the Tank 38H surface sample was 57.6 mg/L, while the sub-surface sample was 106 mg/L. The Tank 43H samples ranged from 50.0 to 51.9 mg/L total uranium. The U-235 percentage was consistent for all four samples at 0.62%. The total uranium and percent U-235 results appear consistent with recent Tank 38H and Tank 43H uranium measurements. The Tank 38H plutonium results show a large difference between the surface and sub-surface sample concentrations and somewhat higher concentrations than previous samples. The Pu-238 concentrationmore » is more than forty times higher in the Tank 38H sub-surface sample than the surface sample. The surface and sub-surface Tank 43H samples contain similar plutonium concentrations and are within the range of values measured on previous samples. The four samples analyzed show silicon concentrations somewhat higher than the previous sample with values ranging from 104 to 213 mg/L.« less

The Impact of Freeze-Thaw Cycles on Epinephrine.

PubMed

Beasley, Heather; Ng, Pearlly; Wheeler, Albert; Smith, William R; McIntosh, Scott E

2015-12-01

Epinephrine is the first-line medical treatment for anaphylaxis, a life-threatening allergic syndrome. To treat anaphylaxis, backcountry recreationalists and guides commonly carry epinephrine autoinjectors. Epinephrine may be exposed to cold temperatures and freezing during expeditions. An epinephrine solution must contain 90% to 115% of the labeled epinephrine amount to meet United States Pharmacopeia standards. The purpose of this study was to determine whether freeze-thaw cycles alter epinephrine concentrations in autoinjectors labeled to contain 1.0 mg/mL epinephrine. A further objective was to determine whether samples continued to meet United States Pharmacopeia concentration standards after freeze-thaw cycles. Epinephrine from 6 autoinjectors was extracted and divided into experimental and control samples. The experimental samples underwent 7 consecutive 12-hour freeze cycles followed by 7 12-hour thaw cycles. The control samples remained at an average temperature of 23.1°C for the duration of the study. After the seventh thaw cycle, epinephrine concentrations were measured using a high-performance liquid chromatography assay with mass spectrometry detection. The mean epinephrine concentration of the freeze-thaw samples demonstrated a statistically significant increase compared with the control samples: 1.07 mg/mL (SD ± 8.78; 95% CI, 1.04 to 1.11) versus 0.96 mg/mL (SD ± 6.81; 95% CI, 0.94 to 0.99), respectively. The maximal mean epinephrine concentration in the experimental freeze-thaw group was 1.12 mg/mL, which still fell within the range of United States Pharmacopeia standards for injectables (0.90 to 1.15 mg/mL). Although every attempt should be made to prevent freezing of autoinjectors, this preliminary study demonstrates that epinephrine concentrations remain within 90% to 115% of 1.0 mg/mL after multiple freeze-thaw cycles. Copyright © 2015 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

Physical Compatibility of Calcium Acetate and Potassium Phosphates in Parenteral Nutrition Solutions Containing Aminosyn II.

PubMed

Zhang, Y; Xu, Q; Trissel, L A; Baker, M B

1999-01-01

Numerous factors have been identified that influence the amount of calcium and phosphates that can remain in solution or will precipitate from parenteral nutrition solutions. Two of the most important such factors are the specific formulation of the amino acid source and the salt form of the calcium source. The purpose of this study was to evaluate the physical compatibility of calcium (as acetate) and potassium phophates in Aminosyn II-based parenteral nutrition solutions. Five representative core parenteral nutrition formulations containing Aminosyn II 2% to 5% were evaluated. Varying amounts of calcium acetate and potassium phosphates were added to samples of the core formulations to identify the concentrations at which precipitation just began to occur. A total of five series of concentrations was tested wiht maxima of calcium 40 mEq/L and phosphates 40 mM/L. The samples were evaluated by visual observation with the unaided eye and by use of a Tyndall beam to accentuate the visibility of small particles and low-level turbidity. For samples not exhibiting visible particles or haze, the turbidity and particle content were measured electronically. Evaluations were performed initially during the first 15 minutes after mixing and after 48 hours of storage at 23 deg and 37 deg C. The precipitation potential of calcium and phosphates in the five representative parenteral nutrition solutions containing Aminosyn II at a a variety of concentrations has been evaluated over a broad range of concentrations has been evaluated over a broad rage of concentrations. The results are presented in tabular form and were used to determine the boundary between compatibility and incompatibility in each of the five core parenteral nutrtion formulations. The boundary lines or compatibility curves were constructed for each of the formulations and are presented graphically.

Biochemical process of low level radioactive liquid simulation waste containing detergent

NASA Astrophysics Data System (ADS)

Kundari, Noor Anis; Putra, Sugili; Mukaromah, Umi

2015-12-01

Research of biochemical process of low level radioactive liquid waste containing detergent has been done. Thse organic liquid wastes are generated in nuclear facilities such as from laundry. The wastes that are cotegorized as hazard and poison materials are also radioactive. It must be treated properly by detoxification of the hazard and decontamination of the radionuclides to ensure that the disposal of the waste meets the requirement of standard quality of water. This research was intended to determine decontamination factor and separation efficiensies, its kinetics law, and to produce a supernatant that ensured the environmental quality standard. The radioactive element in the waste was thorium with activity of 5.10-5 Ci/m3. The radioactive liquid waste which were generated in simulation plant contains detergents that was further processed by aerobic biochemical process using SGB 103 bacteria in a batch reactor equipped with aerators. Two different concentration of samples were processed and analyzed for 212 hours and 183 hours respectively at a room temperature. The product of this process is a liquid phase called as supernatant and solid phase material called sludge. The chemical oxygen demand (COD), biological oxygen demand (BOD), suspended solid (SS), and its alpha activity were analyzed. The results show that the decontamination factor and the separation efficiency of the lower concentration samples are higher compared to the samples with high concentration. Regarding the decontamination factor, the result for 212 hours processing of waste with detergent concentration of 1.496 g/L was 3.496 times, whereas at the detergent concentration of 0.748 g/L was 15.305 times for 183 hours processing. In case of the separation efficiency, the results for both samples were 71.396% and 93.465% respectively. The Bacterial growth kinetics equation follow Monod's model and the decreasing of COD and BOD were first order with the rate constant of 0.01 hour-1.

Biochemical process of low level radioactive liquid simulation waste containing detergent

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

Kundari, Noor Anis, E-mail: nooranis@batan.go.id; Putra, Sugili; Mukaromah, Umi

Research of biochemical process of low level radioactive liquid waste containing detergent has been done. Thse organic liquid wastes are generated in nuclear facilities such as from laundry. The wastes that are cotegorized as hazard and poison materials are also radioactive. It must be treated properly by detoxification of the hazard and decontamination of the radionuclides to ensure that the disposal of the waste meets the requirement of standard quality of water. This research was intended to determine decontamination factor and separation efficiensies, its kinetics law, and to produce a supernatant that ensured the environmental quality standard. The radioactive elementmore » in the waste was thorium with activity of 5.10{sup −5} Ci/m{sup 3}. The radioactive liquid waste which were generated in simulation plant contains detergents that was further processed by aerobic biochemical process using SGB 103 bacteria in a batch reactor equipped with aerators. Two different concentration of samples were processed and analyzed for 212 hours and 183 hours respectively at a room temperature. The product of this process is a liquid phase called as supernatant and solid phase material called sludge. The chemical oxygen demand (COD), biological oxygen demand (BOD), suspended solid (SS), and its alpha activity were analyzed. The results show that the decontamination factor and the separation efficiency of the lower concentration samples are higher compared to the samples with high concentration. Regarding the decontamination factor, the result for 212 hours processing of waste with detergent concentration of 1.496 g/L was 3.496 times, whereas at the detergent concentration of 0.748 g/L was 15.305 times for 183 hours processing. In case of the separation efficiency, the results for both samples were 71.396% and 93.465% respectively. The Bacterial growth kinetics equation follow Monod’s model and the decreasing of COD and BOD were first order with the rate constant of 0.01 hour{sup −1}.« less

Nonpoint-source pollutant discharges of the three major tributaries to Reelfoot Lake, west Tennessee, October 1987-September 1989

USGS Publications Warehouse

Lewis, Michael E.; Garrett, Jerry W.; Hoos, Anne B.

1992-01-01

An investigation of the concentration and loads of nitrogen, phosphorus, and suspended sediment in storm runoff to Reelfoot Lake, in western Tennessee, was conducted from October 1987 through September 1989. Concentrations of selected herbicides also were defined. Reelfoot Lake, with a sur$ace area of about 15,500 acres, is the largest natural lake in Tennessee and an important recreation and fisheries resource. Previous studies showed that the lake is hypereutrophic, a condition caused by high concentrations of nutrients in water and sediments discharged from the three principal tributaries (South Reelfoot Creek, North Reelfoot Creek, and Running Slough) to the lake. Pesticides, including herbicides, have been detected in the lake?s bottom sediments. Storm runoff contributed about 87percent of the total water discharge of the three main tributaries to Reelfoot Lake. South Reelfoot Creek contributed about 4.7 tons per acre per year of suspended sediment, while North Reelfoot Creek contributed about 1.9 tons per acre per year. Running Slough contributed only about 0.31 ton per acre per year of suspended sediment. Most of the suspended sediment was transported by storm runoff between October and March. About 80 percent of the annual streamflow of the three tributaries occurs during these months. The North Reelfoot Creek basin contributed 8.2 pounds per acre per year of total nitrogen and 2.4 pounds per acre per year of total phosphorus. South Reelfoot Creek basin contributed about 6.5 and 1.3 pounds per acre per year of total nitrogen and phosphorus, respectively, while Running Slough basin contributions were 3.4 and 0.86 pounds per acre per year, respectively. The differences in nutrient yields appear to result from more row-crop agriculture and the relatively steeply sloping agricultural land in the North Reelfoot Creek basin. Ninety-one percent of the total nitrogen load and 95 percent of the total phosphorus load in the three streams was transported by storm runof/ Significant diflerences in the mean concentrations of nutrients in runoff were defined between the active agricultural months (April through September) and the inactive months (October through March). Storm-runofS samples were analyzed for II selected triazine herbicides. Alachlor and atrazine were the most commonly detected herbicides. Thirty-two percent of the samples contained detectable levels of alachlor and 93 percent of the samples contained detectable levels of atrazine. Ninety percent of the samples collected during the active agricultural months contained detectable leveki of alachlor and all 29 samples contained detectable levels of atrazine. Sixteen samples exceeded lifetime health-advisory levels for atrazine in drinking water (3 micrograms per liter); two samples collected from the April IS, 1988, storm at North Reelfoot Creek and South Reelfoot Creek contained 42 and 57 micrograms per liter of atrazine, respectively. Concentrations of the other nine triazine herbicides were generally less than the level of detection (0.1 microgram per liter).

Influence of alcohol containing and alcohol free cosmetics on FAEE concentrations in hair. A performance evaluation of ethyl palmitate as sole marker, versus the sum of four FAEEs.

PubMed

Dumitrascu, C; Paul, R; Kingston, R; Williams, Rachel

2018-02-01

Fatty acid ethyl esters (FAEE) are direct metabolites of ethanol and have been shown to be suitable markers for the evaluation of alcohol consumption. Previous research has suggested that the regular use of alcohol containing cosmetic products can influence the concentration of FAEE detected in hair. In this study we investigated the influence of alcohol containing and alcohol free hair cosmetics (hairspray and waxes) on the FAEE concentrations in hair. The effect of cosmetic treatment was measured against the impact on ethyl palmitate in isolation as compared to the sum of four esters. 10 volunteers treated part of their scalp with cosmetic products every day during a 2 month period (alcohol free hairspray n=2, hairspray containing alcohol (42% by volume) n=3, alcohol free wax n=2, wax containing alcohol (11% by volume) n=3). After the 2 month period of cosmetic application hair samples from volunteers were collected from both sides of the scalp. Hair samples were washed with n-heptane, and then cut finely into small pieces. All samples were subjected to clean-up by HS-SPME and then GC PCI-MS/MS for analysis of FAEEs. Comparison of FAEE concentrations between treated and untreated hair showed in some instances that application of hair spray or wax products caused an increase in FAEE levels. Products containing alcohol caused a more substantial increase in alcohol metabolite concentrations in hair when compared to alcohol free products. Three volunteers using an alcohol based hairspray in the study experienced a significant increase in FAEE levels (+27.4%, +205.5%, and +1287.5%), with one of the volunteers showing levels below the cut off for 'abstinence' in the untreated scalp portion, and levels above the cut off for 'chronic excessive consumption' in the treated scalp portion. Performance evaluation of ethyl palmitate as sole marker, compared to the sum of four esters approach suggested that the two quantification approaches react in a very similar manner to the application of hair sprays and waxes. We would suggest that the interpretative value of FAEE hair measurements from people reporting the use of alcohol based hairsprays are treated with caution. Copyright © 2018 Elsevier B.V. All rights reserved.

Arsenic-induced health crisis in peri-urban Moyna and Ardebok villages, West Bengal, India: an exposure assessment study.

PubMed

Maity, Jyoti Prakash; Nath, Bibhash; Kar, Sandeep; Chen, Chien-Yen; Banerjee, Satabdi; Jean, Jiin-Shuh; Liu, Ming-Yie; Centeno, José A; Bhattacharya, Prosun; Chang, Christina L; Santra, Subhas Chandra

2012-10-01

Drinking of arsenic (As)-contaminated groundwater has adverse effects on health of millions of people worldwide. This study aimed to determine the degree of severity of As exposure from drinking water in peri-urban Moyna and Ardebok villages, West Bengal, India. Arsenic concentrations in hair, nail and urine samp les of the individuals were determined. Arsenical dermatosis, keratosis and melanosis were investigated through medical evaluation. We have evaluated the association between As exposure from drinking water, and keratosis and melanosis outcomes. The results showed that 82.7 % of the sampled tube wells contain As concentrations above 10 μg/L, while 57.7 % contain As concentrations above 50 μg/L. The hair, nail and urine As concentrations were positively correlated with As concentrations in drinking water. In our study population, we observed a strong association between As concentrations ranging 51-99 μg/L and keratosis and melanosis outcomes, although the probability decreases at higher concentration ranges perhaps due to switching away from the use of As-contaminated tube wells for drinking and cooking purposes. High As concentrations in hair, nail and urine were observed to be associated with the age of the study population. The level of As concentrations in hair, nail and urine samples of the study population indicated the degree of severity of As exposure in the study region.

Airborne asbestos exposures associated with work on asbestos fire sleeve materials.

PubMed

Blake, Charles L; Harbison, Stephen C; Johnson, Giffe T; Harbison, Raymond D

2011-11-01

Asbestos-containing fire sleeves have been used as a fire protection measure for aircraft fluid hoses. This investigation was conducted to determine the level of airborne asbestos fiber exposure experienced by mechanics who work with fire sleeve protected hoses. Duplicate testing was performed inside a small, enclosed workroom during the fabrication of hose assemblies. Personal air samples taken during this work showed detectable, but low airborne asbestos fiber exposures. Analysis of personal samples (n=9) using phrase contract microscopy (PCM) indicated task duration airborne fiber concentrations ranging from 0.017 to 0.063 fibers per milliliter (f/ml) for sampling durations of 167-198 min, and 0.022-0.14 f/ml for 30 min samples. Airborne chrysotile fibers were detected for four of these nine personal samples, and the resulting asbestos adjusted airborne fiber concentrations ranged from 0.014 to 0.025 f/ml. These results indicate that work with asbestos fire sleeve and fire sleeve protected hose assemblies, does not produce regulatory noncompliant levels of asbestos exposure for persons who handle, cut and fit these asbestos-containing materials. Copyright © 2011 Elsevier Inc. All rights reserved.

Small system for tritium accelerator mass spectrometry

DOEpatents

Roberts, M.L.; Davis, J.C.

1993-02-23

Apparatus for ionizing and accelerating a sample containing isotopes of hydrogen and detecting the ratios of hydrogen isotopes contained in the sample is disclosed. An ion source generates a substantially linear ion beam including ions of tritium from the sample. A radio-frequency quadrupole accelerator is directly coupled to and axially aligned with the source at an angle of substantially zero degrees. The accelerator accelerates species of the sample having different mass to different energy levels along the same axis as the ion beam. A spectrometer is used to detect the concentration of tritium ions in the sample. In one form of the invention, an energy loss spectrometer is used which includes a foil to block the passage of hydrogen, deuterium and [sup 3]He ions, and a surface barrier or scintillation detector to detect the concentration of tritium ions. In another form of the invention, a combined momentum/energy loss spectrometer is used which includes a magnet to separate the ion beams, with Faraday cups to measure the hydrogen and deuterium and a surface barrier or scintillation detector for the tritium ions.

Small system for tritium accelerator mass spectrometry

DOEpatents

Roberts, Mark L.; Davis, Jay C.

1993-01-01

Apparatus for ionizing and accelerating a sample containing isotopes of hydrogen and detecting the ratios of hydrogen isotopes contained in the sample is disclosed. An ion source generates a substantially linear ion beam including ions of tritium from the sample. A radio-frequency quadrupole accelerator is directly coupled to and axially aligned with the source at an angle of substantially zero degrees. The accelerator accelerates species of the sample having different mass to different energy levels along the same axis as the ion beam. A spectrometer is used to detect the concentration of tritium ions in the sample. In one form of the invention, an energy loss spectrometer is used which includes a foil to block the passage of hydrogen, deuterium and .sup.3 He ions, and a surface barrier or scintillation detector to detect the concentration of tritium ions. In another form of the invention, a combined momentum/energy loss spectrometer is used which includes a magnet to separate the ion beams, with Faraday cups to measure the hydrogen and deuterium and a surface barrier or scintillation detector for the tritium ions.

SEPARATION AND ISOLATION OF VOLATILE ORGANIC COMPOUNDS USING VACUUM DISTILLATION WITH GC/MS DETERMINATION

EPA Science Inventory

Vacuum distillation of water, soil, oil, and fish samples is presented as an alternative technique for determining volatile organic compounds (VOCs). Analyses of samples containing VOCs and non-VOCs at 50ppb concentrations were performed to evaluate method limitations. Analyte re...

Chemical composition of blood and bile of the shovelnose sturgeon

USGS Publications Warehouse

Hunn, J.B.; Christenson, L.M.

1977-01-01

Samples of gallbladder bile and blood from shovelnose sturgeons (Scaphirhynchus platorynchus) collected from the Chippewa River, Wisconsin, contained concentrations of Na+, K+, Ca++, Mg++, Cl-, inorganic phosphate, and total cholesterol closely comparable with those reported for similar samples from other species of freshwater sturgeons.

Ammonia concentrations in canine whole blood, EDTA-anticoagulated whole blood, and plasma measured by use of a point-of-care ammonia meter.

PubMed

Odunayo, Adesola; Tobias, Karen M; Okafor, Chika C; Flatland, Bente

2017-11-01

OBJECTIVE To investigate the use of canine whole blood (WB) for measurement of ammonia concentration by use of a point-of-care ammonia meter and to compare results of measuring ammonia concentrations in WB, EDTA-anticoagulated WB, and plasma. ANIMALS 40 client-owned dogs. PROCEDURES A blood sample (2 mL) was obtained from each dog. One drop of WB was immediately applied to a test strip for evaluation with an ammonia meter. The remainder of the blood sample was placed in an EDTA-containing tube, and 1 drop of EDTA-anticoagulated WB was applied to a test strip. The remaining EDTA-anticoagulated WB sample was centrifuged, and the plasma was harvested and placed on ice. One drop of plasma was applied to a test strip; the remainder of the plasma sample was transported on ice and used for ammonia measurement with a reference laboratory instrument. All samples were tested within 1 hour after sample collection. Results were evaluated to detect significant differences in ammonia concentration. RESULTS Ammonia concentrations did not differ significantly between WB and EDTA-anticoagulated WB and between plasma samples measured with the meter and reference laboratory instrument. However, median ammonia concentration was significantly higher in plasma than in WB or EDTA-anti-coagulated WB. CONCLUSIONS AND CLINICAL RELEVANCE Anticoagulant-free WB was a valid sample for measurement by use of the ammonia meter. Plasma samples had higher ammonia concentrations than did WB samples. Results for each sample type should be interpreted by use of specimen- and method-specific reference intervals.

Measurement of atmospheric mercury species with manual sampling and analysis methods in a case study in Indiana

USGS Publications Warehouse

Risch, M.R.; Prestbo, E.M.; Hawkins, L.

2007-01-01

Ground-level concentrations of three atmospheric mercury species were measured using manual sampling and analysis to provide data for estimates of mercury dry deposition. Three monitoring stations were operated simultaneously during winter, spring, and summer 2004, adjacent to three mercury wet-deposition monitoring stations in northern, central, and southern Indiana. The monitoring locations differed in land-use setting and annual mercury-emissions level from nearby sources. A timer-controlled air-sampling system that contained a three-part sampling train was used to isolate reactive gaseous mercury, particulate-bound mercury, and elemental mercury. The sampling trains were exchanged every 6 days, and the mercury species were quantified in a laboratory. A quality-assurance study indicated the sampling trains could be held at least 120 h without a significant change in reactive gaseous or particulate-bound mercury concentrations. The manual sampling method was able to provide valid mercury concentrations in 90 to 95% of samples. Statistical differences in mercury concentrations were observed during the project. Concentrations of reactive gaseous and elemental mercury were higher in the daytime samples than in the nighttime samples. Concentrations of reactive gaseous mercury were higher in winter than in summer and were highest at the urban monitoring location. The results of this case study indicated manual sampling and analysis could be a reliable method for measurement of atmospheric mercury species and has the capability for supplying representative concentrations in an effective manner from a long-term deposition-monitoring network. ?? 2007 Springer Science+Business Media B.V.

Nondestructive characterization of municipal-solid-waste-contaminated surface soil by energy-dispersive X-ray fluorescence and low-Z (atomic number) particle electron probe X-ray microanalysis.

PubMed

Gupta, Dhrubajyoti; Ghosh, Rita; Mitra, Ajoy K; Roy, Subinit; Sarkar, Manoranjan; Chowdhury, Subhajit; Bhowmik, Asit; Mukhopadhyay, Ujjal; Maskey, Shila; Ro, Chul-Un

2011-11-01

The long-term environmental impact of municipal solid waste (MSW) landfilling is still under investigation due to the lack of detailed characterization studies. A MSW landfill site, popularly known as Dhapa, in the eastern fringe of the metropolis of Kolkata, India, is the subject of present study. A vast area of Dhapa, adjoining the current core MSW dump site and evolving from the raw MSW dumping in the past, is presently used for the cultivation of vegetables. The inorganic chemical characteristics of the MSW-contaminated Dhapa surface soil (covering a 2-km stretch of the area) along with a natural composite (geogenic) soil sample (from a small countryside farm), for comparison, were investigated using two complementary nondestructive analytical techniques, energy-dispersive X-ray fluorescence (EDXRF) for bulk analysis and low-Z (atomic number) particle electron probe X-ray microanalysis (low-Z particle EPMA) for single-particle analysis. The bulk concentrations of K, Rb, and Zr remain almost unchanged in all the soil samples. The Dhapa soil is found to be polluted with heavy metals such as Cu, Zn, and Pb (highly elevated) and Ti, Cr, Mn, Fe, Ni, and Sr (moderately elevated), compared to the natural countryside soil. These high bulk concentration levels of heavy metals were compared with the Ecological Soil Screening Levels for these elements (U.S. Environment Protection Agency) to assess the potential risk on the immediate biotic environment. Low-Z particle EPMA results showed that the aluminosilicate-containing particles were the most abundant, followed by SiO2, CaCO3-containing, and carbonaceous particles in the Dhapa samples, whereas in the countryside sample only aluminosilicate-containing and SiO2 particles were observed. The mineral particles encountered in the countryside sample are solely of geogenic origin, whereas those from the Dhapa samples seem to have evolved from a mixture of raw dumped MSW, urban dust, and other contributing factors such as wind, precipitation, weather patterns, farming, and water logging, resulting in their diverse chemical compositions and the abundant observation of carbonaceous species. Particles containing C and P were more abundant in the Dhapa samples than in the countryside soil sample, suggesting that MSW-contaminated soils are more fertile. However, the levels of particles containing potentially toxic heavy metals such as Cr, Mn, Ni, Cu, Zn, and/or Pb in the Dhapa samples were significant, corroborated by their high bulk concentration levels (EDXRF), causing deep concern for the immediate environment and contamination of the food chain through food crops.

Field investigation of the quality of fresh and aged leachates from selected landfills receiving e-waste in an arid climate

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

Kiddee, Peeranart; Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, Mawson Lakes Campus, Adelaide 5095; Naidu, Ravi, E-mail: ravi.naidu@unisa.edu.au

Highlights: • E-waste comprises approximately 6% of the waste mass going to landfill in South Australia. • Significant amounts of metal(loids)s and PBDEs are released from e-waste mixed with municipal solid in landfill leachates. • Significantly elevated concentrations of lead and PBDEs are detected in groundwater wells downgradient of landfills. • Significant temporal variation exists in electrical conductivity and in the concentrations of As, Cd and Pb in leachates. - Abstract: The management of electronic waste (e-waste) is a serious problem worldwide and much of it is landfilled. A survey of four selected landfills in an arid region of Southmore » Australia was conducted to determine the proportion of e-waste in municipal waste and the properties of each landfill site. Leachate and groundwater samples were collected upgradient and downgradient of the landfills for analysis of polybrominated diphenyl ethers (PBDEs) and 14 metals and metalloids, including Al, As, Ba, Be, Cd, Co, Cr, Cu, Fe, Ni, Pb, Sb, V and Zn. Our data demonstrate that the selected landfills in South Australia continue to receive municipal waste containing in excess of 6%, or 25,000 tonnes per year, of e-waste. The leachates and groundwater collected from the landfills contained significantly elevated concentrations of Pb with the highest concentration in groundwater of 38 μg/l, almost four times higher than the Australian drinking water guideline of 10 μg/l. The presence of PBDEs was detected in both leachate and groundwater samples. Total PBDEs values of 2.13–59.75 ng/l in leachate samples were 10 times higher than in groundwater samples, which recorded a range of 0.41–6.53 ng/l at all sites. Moreover, the concentrations of metals and metalloids in sampled groundwater contained elevated levels of Al, As, Fe, Ni and Pb that exceeded Australian drinking water guideline values. For these reasons potential leaching of these contaminants is of concern and while difficult to attribute elevated contaminant levels to e-waste, we do not recommend continued disposal of e-waste in old landfills that were not originally designed to contain leachates. The survey also revealed temporal variation in the electrical conductivity and concentrations of As, Cd and Pb present in leachates of landfills in arid Mediterranean climates. These results are consistent with the marked variations in rainfall patterns observed for such climates. The solute concentration (EC and other ions including As, Cd and Pb) declines in the leachates during wet winter months (June to September), in contrast to tropical countries where such changes are observed during wet summer months.« less

[Concentration of biocides in indoor rooms using pyrethroids as an example].

PubMed

Walker, G; Keller, R; Beckert, J; Butte, W

1994-06-01

Pyrethroids are an analogous substance group to one of the oldest known, naturally occurring insecticides pyrethrum and have replaced a number of pesticides such as Lindane, DDT and PCP on the market. Biocides are more persistent indoors than in nature, which could lead to permanent health hazards for the people concerned. Within a few days after application pyrethroids are rarely detected in room air but can be traced for a long time on textiles, furniture and in dust particles (3, 8). The investigation results of approx. 100 analyses from dust and carpet samples show that approx. 1/3 of these samples are positive for at least one pyrethroid and contain a concentration of > 2 mg substance per kg sample. The evaluation of 35 air samples taken from rooms where substances containing pyrethroids had been used at least a month prior to the investigation (the samples were sampled on active charcoal or Chromosorb) showed that pyrethroids could no longer be traced above the detection limit of 0.05-0.1 micrograms/m3. We therefore think that when investigating a contamination of rooms by biocides it is more advisable to determine pyrethroid and its synergists in the suspended dust portion and corresponding dust sample rather than analysing air by adsorption to active charcoal, Chromosorb or other carrier materials. From the observed concentrations of biocides one could conclude that in an indoor setting secondary contamination by biocides plays a more significant role in the total-body-load than that of air contamination.

Origin of Tungsten Excess in Komatiites

NASA Astrophysics Data System (ADS)

Becker, H.; Brandon, A. D.; Walker, R. J.

2004-12-01

The limited database available for W abundances in komatiites (n=7, Newsom et al., 1996) suggests that when melting and fractional crystallization effects are filtered out, these komatiites have about 10 times higher W, compared to other mantle-derived mafic-ultramafic magmas (MORB, OIB). The excess of W in the komatiites relative to lithophile highly incompatible elements becomes obvious when compared with the low concentrations of the light REE Ce and Nd (about 1-2 ug/g in many komatiites, compared to > 10 ug/g in most MORB and OIB). In order to increase the komatiite W database, komatiite samples from Phanerozoic (Gorgona Island) and Archean terraines (Boston Creek/Canada, Belingwe/South Africa, 2.7 Ga) were dissolved and W was separated in order to obtain W concentrations by isotope dilution. Except for one sample from Gorgona Island with low W (23 ng/g), samples from all three locales show high W (516 to 2643 ng/g), with most samples containing near 700 ng/g W. Three Hawaiian picrites (H23, LO-02-04, MK-1-6) were also analyzed for comparative purposes and contain 75, 163 and 418 ng/g W, respectively. The W concentrations in the Hawaiian picrites are comparable or lower than W concentrations in Hawaiian tholeiites (Newsom et al., 1996). Mass balance considerations suggest that it is unlikely that the W excess in komatiites reflects W contributions to the mantle sources of komatiites from the outer core. The W enrichment could result from shallow-level alteration processes if primary W abundances of komatiites were low and W was added via fluids, containing W and other fluid-mobile elements derived from crustal rocks. Because most W in such samples would be of crustal origin, small contributions from the outer core may be difficult to detect using 182W systematics (Schersten et al., 2003).

Determination of 238u/235u, 236u/238u and uranium concentration in urine using sf-icp-ms and mc-icp-ms: an interlaboratory comparison.

PubMed

Parrish, Randall R; Thirlwall, Matthew F; Pickford, Chris; Horstwood, Matthew; Gerdes, Axel; Anderson, James; Coggon, David

2006-02-01

Accidental exposure to depleted or enriched uranium may occur in a variety of circumstances. There is a need to quantify such exposure, with the possibility that the testing may post-date exposure by months or years. Therefore, it is important to develop a very sensitive test to measure precisely the isotopic composition of uranium in urine at low levels of concentration. The results of an interlaboratory comparison using sector field (SF)-inductively coupled plasma-mass spectrometry (ICP-MS) and multiple collector (MC)-ICP-MS for the measurement of uranium concentration and U/U and U/U isotopic ratios of human urine samples are presented. Three urine samples were verified to contain uranium at 1-5 ng L and shown to have natural uranium isotopic composition. Portions of these urine batches were doped with depleted uranium (DU) containing small quantities of U, and the solutions were split into 100 mL and 400 mL aliquots that were subsequently measured blind by three laboratories. All methods investigated were able to measure accurately U/U with precisions of approximately 0.5% to approximately 4%, but only selected MC-ICP-MS methods were capable of consistently analyzing U/U to reasonable precision at the approximately 20 fg L level of U abundance. Isotope dilution using a U tracer demonstrates the ability to measure concentrations to better than +/-4% with the MC-ICP-MS method, though sample heterogeneity in urine samples was shown to be problematic in some cases. MC-ICP-MS outperformed SF-ICP-MS methods, as was expected. The MC-ICP-MS methodology described is capable of measuring to approximately 1% precision the U/U of any sample of human urine over the entire range of uranium abundance down to <1 ng L, and detecting very small amounts of DU contained therein.

A quality-assurance assessment for constituents reported by the national atmospheric deposition program and the national trends network

NASA Astrophysics Data System (ADS)

See, Randolph B.; Schroder, LeRoy J.; Willoughby, Timothy C.

A continuing quality-assurance program has been operated by the U.S. Geological Survey to evaluate any bias introduced by routine handling, shipping, and laboratory analyses of wet-deposition samples collected in the National Atmospheric Deposition Program (NADP) and National Trends Network (NTN). Blind-audit samples having a variety of constituent concentrations and values were selected. Only blind-audit samples with constituent concentrations and values less than the 95th-percentile concentration for natural wet-deposition samples were included in the analysis. Of the major ions, there was a significant increase of Ca 2+, Mg 2+, Na 2+, K +, SO 42- and Cl -1 in samples handled according to standard protocols and shipped in NADP/NTN sample-collection buckets. For 1979-1987, graphs of smoothed data showing the estimated contamination in blind-audit samples indicate a decrease in the median concentration and ranges of Ca 2+, Mg 2+ and SO 42- contamination of blind-audit samples shipped in sample-collection buckets. Part of the contamination detected in blind-audit samples can be attributed to contact with the sample-collection bucket and lid; however, additional sources also seem to contaminate the blind-audit sample. Apparent decreases in the magnitude and range of sample contamination may be caused by differences in sample-collection bucket- and lid-washing procedures by the NADP/NTN Central Analytical Laboratory. Although the degree of bias is minimal for most constituents, summaries of the NADP/NTN data base may contain overestimates of Ca 2+, Mg 2+, Na -, K + and SO 42- and Cl - concentrations, and underestimates of H + concentrations.

A quality-assurance assessment for constituents reported by the National Atmospheric Deposition Program and the National Trends Network

USGS Publications Warehouse

See, R.B.; Schroder, L.J.; Willoughby, T.C.

1989-01-01

A continuing quality-assurance program has been operated by the U.S. Geographical Survey to evaluate any bias introduced by routine handling, shipping, and laboratory analyses of wet-deposition samples collected in the National Atmospheric Deposition Program (NADP) and National Trends Network (NTN). Blind-audit samples having a variety of constituent concentrations and values were selected. Only blind-audit samples with constituent concentrations and values less than the 95th-percentile concentration for natural wet-deposition samples were included in the analysis. Of the major ions, there was a significant increase of Ca2+, Mg2+, K+ SO42+ and Cl- in samples handled according to standard protocols and shipped in NADP/NTN sample-collection buckets. For 1979-1987, graphs of smoothed data showing the estimated contaminations in blind-audit samples indicate a decrease in the median concentration and ranges of Ca2+, Mg2+ and SO42- contamination of blind-audit samples shipped in sample-collection buckets. Part of the contamination detected in blind-audit samples can be attributed to contact with the sample-collection bucket and lid; however, additional sources also seem to contaminate the blind-audit sample. Apparent decreases in the magnitude and range of sample contamination may be caused by differences in sample-collection bucket- and lid-washing procedures by the NADP/NTN Central Analytical Laboratory. Although the degree of bias is minimal for most constituents, summaries of the NADP/NTN data base may contain overestimates of Ca2+, Mg2+, Na-, K+, SO42- and Cl- concentrations, and underestimates of H+ concentrations.

Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Vermejo Project area and the Maxwell National Wildlife Refuge, Colfax County, northeastern New Mexico, 1993

USGS Publications Warehouse

Bartolino, J.R.; Garrabrant, L.A.; Wilson, Mark; Lusk, J.D.

1996-01-01

Based on findings of limited studies during 1989-92, a reconnaissance investigation was conducted in 1993 to assess the effects of the Vermejo Irrigation Project on water quality in the area of the project, including the Maxwell National Wildlife Refuge. This project was part of a U.S. Department of the Interior National Irrigation Water-Quality Program to determine whether irrigation drainage has caused or has the potential to cause significant harmful effects on human health, fish, and wildlife and whether irrigation drainage may adversely affect the suitability of water for other beneficial uses. For this study, samples of water, sediment, and biota were collected from 16 sites in and around the Vermejo Irrigation Project prior to, during the latter part of, and after the 1993 irrigation season (April, August-September, and November, respectively). No inorganic constituents exceeded U.S. Environmental Protection Agency drinking-water standards. The State of New Mexico standard of 750 micrograms per liter for boron in irrigation water was exceeded at three sites (five samples), though none exceeded the livestock water standard of 5,000 micrograms per liter. Selenium concentrations exceeded the State of New Mexico chronic standard of 2 micrograms per liter for wildlife and fisheries water in at least eight samples from five sites. Bottom-sediment samples were collected and analyzed for trace elements and compared to concentrations of trace elements in soils of the Western United States. Concentrations of three trace elements at eight sites exceeded the upper values of the expected 95-percent ranges for Western U.S. soils. These included molybdenum at one site, selenium at seven sites, and uranium at four sites. Cadmium and copper concentrations exceeded the National Contaminant Biomonitoring Program 85th percentile in fish from six sites. Average concentrations of selenium in adult brine flies (33.7 mg/g dry weight) were elevated above concentrations in other invertebrates. Concentrations of other elements were below their respective toxicity levels. Plants, invertebrates, fish, and fish fillets were collected and analyzed. These analyses were compared to diagnostic criteria and to each other to determine the extent of bioaccumulation of trace elements. Plants contained larger dry weight concentrations of aluminum, arsenic, boron, chromium, iron, lead, magnesium, manganese, nickel, and vanadium than invertebrates and fish. Adult brine flies, gathered from playas, contained larger geometric mean dry weight concentrations of boron, magnesium, and selenium than other invertebrates. Of all samples collected, the largest mercury concentrations were found in fish fillets, although these concentrations were below levels of concern. Mercury and selenium bioaccumulation was evident in various habitats of the study area. Biological samples from Natural playa, an endemic wetland, and Half playa, a playa that receives additional water through seepage and irrigation delivery canals, generally had elevated concentrations of boron, iron, magnesium, and selenium than samples from reservoir and river sites. Selenium concentrations were lowest in biota from the two reservoir sites, although a wetland immediately downstream from the dam impounding Lake No. 13 (created by seepage from the reservoir) had elevated concentrations of selenium in biota. The geometric mean selenium concentration of whole-fish samples, except those from Lakes No. 13 and No. 14, exceeded the 5-mg/g dry weight selenium concentration that demarcates the approximate lower limit of the threshold range of concentrations that have been associated with adverse effects on piscine reproduction. Biota collected on and in the area around Maxwell National Wildlife Refuge contained concentrations of selenium that are in the low

Thyroglobulin assay in fluids from lymph node fine needle-aspiration washout: influence of pre-analytical conditions.

PubMed

Casson, Florence Boux de; Moal, Valérie; Gauchez, Anne-Sophie; Moineau, Marie-Pierre; Sault, Corinne; Schlageter, Marie-Hélène; Massart, Catherine

2017-04-01

The aim of this study was to evaluate the pre-analytical factors contributing to uncertainty in thyroglobulin measurement in fluids from fine-needle aspiration (FNA) washout of cervical lymph nodes. We studied pre-analytical stability, in different conditions, of 41 samples prepared with concentrated solutions of thyroglobulin (FNA washout or certified standard) diluted in physiological saline solution or buffer containing 6% albumin. In this buffer, over time, no changes in thyroglobulin concentrations were observed in all storage conditions tested. In albumin free saline solution, thyroglobulin recovery rates depended on initial sample concentrations and on modalities of their conservation (in conventional storage tubes, recovery mean was 56% after 3 hours-storage at room temperature and 19% after 24 hours-storage for concentrations ranged from 2 to 183 μg/L; recovery was 95%, after 3 hours or 24 hours-storage at room temperature, for a concentration of 5,656 μg/L). We show here that these results are due to non-specific adsorption of thyroglobulin in storage tubes, which depends on sample protein concentrations. We also show that possible contamination of fluids from FNA washout by plasma proteins do not always adequately prevent this adsorption. In conclusion, non-specific adsorption in storage tubes strongly contributes to uncertainty in thyroglobulin measurement in physiological saline solution. It is therefore recommended, for FNA washout, to use a buffer containing proteins provided by the laboratory.

Application of a bacterial whole cell biosensor for the rapid detection of cytotoxicity in heavy metal contaminated seawater.

PubMed

Cui, Zhisong; Luan, Xiao; Jiang, Huichao; Li, Qian; Xu, Guangfei; Sun, Chengjun; Zheng, Li; Song, Yizhi; Davison, Paul A; Huang, Wei E

2018-06-01

A toxicity biosensor Acinetobacter baylyi Tox2 was constructed with the host strain A. baylyi ADP1 harboring a new and medium-copy-number plasmid pWH1274_lux, and was applied to detect the cytotoxicity of heavy metal contaminated seawater. The gene cassette luxCDABE was controlled by constitutively expressed promoter P tet on pWH1274_lux and the bioluminescence intensity of the biosensor reduces in proportional to the concentrations of toxic compounds. A. baylyi Tox2 exhibits tolerance to salinity, hence it is applicable to seawater samples. A. baylyi Tox2 and Mugilogobius chulae were exposed to different concentrations of heavy metals (Hg 2+ , Zn 2+ , Cu 2+ , and Cd 2+ ) in artificial seawater for performance comparison and Pearson correlation analysis showed a significant correlation (p < 0.01) between A. baylyi Tox2 toxicity detection and the fish (M. chulae) exposure test. This suggests that the performance of A. baylyi Tox2 is comparable to the conventional fish toxicity test in terms of cytotoxicity detection of heavy metal contaminated seawater. Furthermore, A. baylyi Tox2 was used to evaluate cytotoxicity of field-collected seawater samples. The results indicate that there was a significant correlation between the luminescence inhibition ratio (IR) of A. baylyi Tox2 and heavy metal concentrations detected by ICP-MS in the samples. Two seawater samples, which contained a high concentration of total heavy metals, exhibited stronger cytotoxicity than the samples containing low concentrations of heavy metals. In conclusion, A. baylyi Tox2 can be used as an alternative tool to aquatic animals for the evaluation of the cytotoxicity of heavy metal contamination in the marine environment. Copyright © 2018 Elsevier Ltd. All rights reserved.

Quality of water and bed material in streams of Logan Township, Gloucester County, New Jersey, 1984

USGS Publications Warehouse

Hochreiter, J.J.; Kozinski, Jane

1985-01-01

The surface water and surficial-bed material at seven stations on three streams in Logan Township, Gloucester County, New Jersey, were sampled in the fall of 1984. Samples of water were analyzed for volatile organic compounds, trace metals, and organochlorine and organophosphorous compounds. Surficial-bed material was analyzed for extractable trace metals and organochlorine compounds. Water samples from two closely spaced sampling locations along Raccoon Creek contained elevated concentrations of methylene chloride (455 and 1800 micrograms/L, respectively), a volatile organic solvent. Bed-material samples taken from Little Timber and Birch Creeks contained elevated levels of trace metals and organochlorine compounds, including polychlorinated biphenyls (PCB's). Contaminant concentrations in bed-material samples taken from Raccoon Creek were much lower than those found previously by the U.S. Geological Survey in 1980. Only a trace of PCB 's was detected in any bed material sample taken from Racoon Creek. Gas chromatographic flame-ionization detector scans, performed on solvent extracts of all water and sediment samples, were useful in characterizing the presence or absence of organic contaminants in those samples. Changes in the character of organic contamination along the reaches of two streams were apparent when the fingerprints of chromatograms representing upstream sites were compared to those representing downstream sites. (Author 's abstract)

Determination of alkylbenzenesulfonate surfactants in groundwater using macroreticular resins and carbon-13 nuclear magnetic resonance spectrometry

USGS Publications Warehouse

Thurman, E.M.; Willoughby, T.; Barber, L.B.; Thorn, K.A.

1987-01-01

Alkylbenzenesulfonate surfactants were determined in groundwater at concentrations as low as 0.3 mg/L. The method uses XAD-8 resin for concentration, followed by elution with methanol, separation of anionic and nonionic surfactants by anion exchange, quantitation by titration, and identification by 13C nuclear magnetic resonance spectrometry. Laboratory standards and field samples containing straight-chain and branched-chain alkylbenzenesulfonates, sodium dodecyl sulfate, and alkylbenzene ethoxylates were studied. The XAD-8 extraction of surfactants from groundwater was completed in the field, which simplified sample preservation and reduced the cost of transporting samples.

Recovery of Precious and Base Metals from Waste Printed Circuit Boards Using a Sequential Leaching Procedure

NASA Astrophysics Data System (ADS)

Batnasan, Altansukh; Haga, Kazutoshi; Shibayama, Atsushi

2018-02-01

This paper considers the issue of recycling of waste printed circuit boards (WPCBs) containing precious and base metals in appreciable amounts. High-pressure oxidative leaching (HPOL) with dilute sulfuric acid resulted in removal of a significant amount of base metals from a WPCB ash sample obtained by incineration at 800°C. The parameters investigated in the precious metal leaching from WPCB residue after HPOL included the sulfuric acid concentration, thiourea concentration, oxidant concentration, leaching temperature, and leaching time. Recovery of gold, silver, and palladium of 100%, 81%, and 13% from the WPCB residue sample was achieved by thiourea leaching under optimized conditions. The results show that the efficiency of precious metal dissolution from the WPCB sample using thiourea solution depended strongly on the concentration of both thiourea and oxidant.

Recovery of Precious and Base Metals from Waste Printed Circuit Boards Using a Sequential Leaching Procedure

NASA Astrophysics Data System (ADS)

Batnasan, Altansukh; Haga, Kazutoshi; Shibayama, Atsushi

2017-12-01

This paper considers the issue of recycling of waste printed circuit boards (WPCBs) containing precious and base metals in appreciable amounts. High-pressure oxidative leaching (HPOL) with dilute sulfuric acid resulted in removal of a significant amount of base metals from a WPCB ash sample obtained by incineration at 800°C. The parameters investigated in the precious metal leaching from WPCB residue after HPOL included the sulfuric acid concentration, thiourea concentration, oxidant concentration, leaching temperature, and leaching time. Recovery of gold, silver, and palladium of 100%, 81%, and 13% from the WPCB residue sample was achieved by thiourea leaching under optimized conditions. The results show that the efficiency of precious metal dissolution from the WPCB sample using thiourea solution depended strongly on the concentration of both thiourea and oxidant.

Application of Lemongrass Oil-Containing Polylactic Acid Films to the Packaging of Pork Sausages.

PubMed

Yang, Hyun-Ju; Song, Kyung Bin

2016-01-01

Polylactic acid (PLA) is a biodegradable and renewable polymer, which represents a valuable alternative to plastic packaging films, often associated with environmental problems. In this study, we tested the suitability of PLA as a biodegradable packaging film and assessed the antimicrobial activity of lemongrass oil (LO), incorporated into the PLA film in different concentrations. To obtain the optimal physical properties for PLA films, tensile strength, elongation at break, and water vapor permeability were measured under different preparation conditions. In addition, the antimicrobial activity of the LO contained in the PLA film against Listeria monocytogenes was investigated by disc diffusion and viable cell count. Among all concentrations tested, 2% LO was the most suitable in terms of antimicrobial activity and physical properties of the PLA film. Based on these results, we used the PLA film containing 2% LO to pack pork sausages; after 12 d of storage at 4℃, the population of inoculated L. monocytogenes in the sausage samples wrapped with the PLA film containing 2% LO was reduced by 1.47 Log CFU/g compared with the control samples. Our data indicate that PLA films containing 2% LO represent a valuable means for antimicrobial sausage packaging.

Application of Lemongrass Oil-Containing Polylactic Acid Films to the Packaging of Pork Sausages

PubMed Central

2016-01-01

Polylactic acid (PLA) is a biodegradable and renewable polymer, which represents a valuable alternative to plastic packaging films, often associated with environmental problems. In this study, we tested the suitability of PLA as a biodegradable packaging film and assessed the antimicrobial activity of lemongrass oil (LO), incorporated into the PLA film in different concentrations. To obtain the optimal physical properties for PLA films, tensile strength, elongation at break, and water vapor permeability were measured under different preparation conditions. In addition, the antimicrobial activity of the LO contained in the PLA film against Listeria monocytogenes was investigated by disc diffusion and viable cell count. Among all concentrations tested, 2% LO was the most suitable in terms of antimicrobial activity and physical properties of the PLA film. Based on these results, we used the PLA film containing 2% LO to pack pork sausages; after 12 d of storage at 4℃, the population of inoculated L. monocytogenes in the sausage samples wrapped with the PLA film containing 2% LO was reduced by 1.47 Log CFU/g compared with the control samples. Our data indicate that PLA films containing 2% LO represent a valuable means for antimicrobial sausage packaging. PMID:27433114

Characterization results for the October 2015-Tank for farm 3H evaporator overhead examples

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

Nicholson, J. C.

2016-01-28

This report contains the radioanalytical results of the 3H evaporator overhead sample received at SRNL on October 13, 2015. Specifically, concentrations of 137Cs, 90Sr, and 129I are reported and compared to the corresponding Waste Acceptance Criteria (WAC) limits of the Effluent Treatment Project (ETP) Waste Water Collection Tank (WWCT) (rev. 6). All of the radionuclide concentrations in the sample were found to be in compliance with the ETP WAC limits.

Concentration of trace elements on branded cigarette in Malaysia

NASA Astrophysics Data System (ADS)

Azman, Muhammad Azfar; Yasir, Muhamad Samudi; Rahman, Irman Abdul; Hamzah, Suhaimi; Rahman, Shamsiah Abdul; Elias, Md Suhaimi; Abdullah, Nazaratul Ashifa; Hashim, Azian; Shukor, Shakirah Abd

2016-01-01

Tobacco is a plant that is used as a recreational drug since the beginning of its use by the Native Americans. Now with the development of the tobacco industry, smoking has become a norm for the public in Malaysia. Trace elements in plants are mostly due to the uptake processes from the soils into the roots of the plants. The concentration of the elements may also be influenced by the elements contained in the water and also fertilizers. This paper aim to analyze the concentration of the trace elements contained in the branded cigarettes sold in Malaysia by utilizing the neutron activation analysis. The tobaccos were taken out from the cigarettes. The collected samples were air dried and passed through 2 mm sieve. Instrumental Neutron Activation Analysis (NAA) has been used for the determination of trace elements. Samples were activated in the Nuclear Malaysia Triga Mark II reactor with a neutron flux of 2.0 x 1012 n cm-2 s-1. The samples then were analyzed using ORTEC Gamma Spectrometer a co-axial n-type HPGe detector with resolution of 2.0 keV at 1332 keV and relative efficiency of 20%. The data obtained could help in assessing the concentration of the trace elements that complying with the standard limitation dose proposed by World Health Organization (WHO).

Neonicotinoid Insecticide Residues in Surface Water and Soil Associated with Commercial Maize (Corn) Fields in Southwestern Ontario

PubMed Central

Schaafsma, Arthur; Limay-Rios, Victor; Baute, Tracey; Smith, Jocelyn; Xue, Yingen

2015-01-01

Neonicotinoid insecticides have come under scrutiny for their potential unintended effects on non-target organisms, particularly pollinators in agro-ecosystems. As part of a larger study of neonicotinoid residues associated with maize (corn) production, 76 water samples within or around the perimeter of 18 commercial maize fields and neighbouring apiaries were collected in 5 maize-producing counties of southwestern Ontario. Residues of clothianidin (mean = 2.28, max. = 43.60 ng/mL) and thiamethoxam (mean = 1.12, max. = 16.50 ng/mL) were detected in 100 and 98.7% of the water samples tested, respectively. The concentration of total neonicotinoid residues in water within maize fields increased six-fold during the first five weeks after planting, and returned to pre-plant levels seven weeks after planting. However, concentrations in water sampled from outside the fields were similar throughout the sampling period. Soil samples from the top 5 cm of the soil profile were also collected in these fields before and immediately following planting. The mean total neonicotinoid residue was 4.02 (range 0.07 to 20.30) ng/g, for samples taken before planting, and 9.94 (range 0.53 to 38.98) ng/g, for those taken immediately after planting. Two soil samples collected from within an conservation area contained detectable (0.03 and 0.11 ng/g) concentrations of clothianidin. Of three drifted snow samples taken, the drift stratum containing the most wind-scoured soil had 0.16 and 0.20 ng/mL mainly clothianidin in the melted snow. The concentration was at the limit of detection (0.02 ng/mL) taken across the entire vertical profile. With the exception of one sample, water samples tested had concentrations below those reported to have acute, chronic or sublethal effects to honey bees. Our results suggest that neonicotinoids may move off-target by wind erosion of contaminated soil. These results are informative to risk assessment models for other non-target species in maize agro-ecosytems. PMID:25710560

Discrepant post filter ionized calcium concentrations by common blood gas analyzers in CRRT using regional citrate anticoagulation.

PubMed

Schwarzer, Patrik; Kuhn, Sven-Olaf; Stracke, Sylvia; Gründling, Matthias; Knigge, Stephan; Selleng, Sixten; Helm, Maximilian; Friesecke, Sigrun; Abel, Peter; Kallner, Anders; Nauck, Matthias; Petersmann, Astrid

2015-09-08

Ionized calcium (iCa) concentration is often used in critical care and measured using blood gas analyzers at the point of care. Controlling and adjusting regional citrate anticoagulation (RCA) for continuous renal replacement therapy (CRRT) involves measuring the iCa concentration in two samples: systemic with physiological iCa concentrations and post filter samples with very low iCa concentrations. However, modern blood gas analyzers are optimized for physiological iCa concentrations which might make them less suitable for measuring low iCa in blood with a high concentration of citrate. We present results of iCa measurements from six different blood gas analyzers and the impact on clinical decisions based on the recommendations of the dialysis' device manufacturer. The iCa concentrations of systemic and post filter samples were measured using six distinct, frequently used blood gas analyzers. We obtained iCa results of 74 systemic and 84 post filter samples from patients undergoing RCA for CRRT at the University Medicine of Greifswald. The systemic samples showed concordant results on all analyzers with median iCa concentrations ranging from 1.07 to 1.16 mmol/L. The medians of iCa concentrations for post filter samples ranged from 0.21 to 0.50 mmol/L. Results of >70% of the post filter samples would lead to major differences in decisions regarding citrate flow depending on the instrument used. Measurements of iCa in post filter samples may give misleading information in monitoring the RCA. Recommendations of the dialysis manufacturer need to be revised. Meanwhile, little weight should be given to post filter iCa. Reference methods for low iCa in whole blood containing citrate should be established.

Quality of ground water in the Puget sound region, Washington, 1981

USGS Publications Warehouse

Turney, G.L.

1986-01-01

Groundwater from more than 100 sites in the Puget Sound region, Washington, was sampled and analyzed in 1981 for pH, specific conductance, and concentrations of fecal coliform bacteria, major ions, and dissolved iron, manganese, and nitrate. 20% of the samples were analyzed for concentrations of dissolved trace metals including aluminum, arsenic, barium, cadmium, chromium, copper, lead, mercury, selenium, silver, and zinc. The predominant water types were calcium bicarbonate and calcium-magnesium bicarbonate. Some wells in San Juan and Island Counties contained sodium chloride as a result of seawater intrusion. Dissolved solids concentrations were generally < 150 mg/L. Iron concentrations > 300 micrograms/L in 14% of all samples. Manganese concentrations > 50 micrograms/L in 40% of all samples. Trace-metal concentrations were generally < 10 mg/L , except for barium, copper, lead, and zinc. Nitrate concentrations were < 1.0 mg/L in water for over 75% of the sites. Concentrations > 1.0 mg/L in samples from Skagit, Whatcom , and Pierce Counties, were probably due to agricultural activities or septic tanks. Fecal coliform bacteria were detected in isolated instances. EPA drinking water regulations were exceeded only in isolated instances, except for widespread excessive iron and manganese concentrations. The historical data for the region were also evaluated for the same constituents. There are quantitative differences between historical and 1981 data, but they may be due to inconsistencies in data collection and analytical methods. (Author 's abstract)

Cross Validation of Two Partitioning-Based Sampling Approaches in Mesocosms Containing PCB Contaminated Field Sediment, Biota, and Activated Carbon Amendment

EPA Science Inventory

The Gold Standard for determining freely dissolved concentrations (Cfree) of hydrophobic organic compounds in sediment interstitial water would be in situ deployment combined with equilibrium sampling, which is generally difficult to achieve. In the present study, ex situ equilib...

US EPA Base Study Standard Operating Procedure for Sampling Volatile Organic Compounds in Indoor Air Using Evacuated Canisters

EPA Pesticide Factsheets

The objective of this procedure is to collect a representative sample of air containing volatile organic compound (VOC) contaminants present in an indoor environment using an evacuated canister, and to subsequently analyze the concentration of VOCs, as selected by EPA.

Herbicides and degradates in shallow aquifers of Illinois: Spatial and temporal trends

USGS Publications Warehouse

Mills, P.C.; Kolpin, D.W.; Scribner, E.A.; Thurman, E.M.

2005-01-01

During the fall of 2000, the occurrence was examined of 16 herbicides and 13 herbicide degradates in samples from 55 wells in shallow aquifers underlying grain producing regions of Illinois. Herbicide compounds with concentrations above 0.05 ??g/L were detected in 56 percent of the samples. No concentrations exceeded regulatory drinking water standards. The six most frequently detected compounds were degradates. Water age was an important factor in determining vulnerability of ground water to transport of herbicide compounds. Unconsolidated aquifers, which were indicated to generally contain younger ground water than bedrock aquifers, had a higher occurrence of herbicides (73 percent of samples) than bedrock aquifers (22 percent). Temporal analysis to determine if changes in concentrations of selected herbicides and degradates could be observed over a near decadal period indicated a decrease in detection frequency (25 to 18 percent) between samplings in 1991 and 2000. Over this period, significant differences in concentrations were observed for atrazine (decrease) and total acetochlor (increase). The increase in acetochlor compound concentrations corresponds to an increase in acetochlor use during the study period, while the decrease in atrazine concentrations corresponds to relatively consistent use of atrazine. Changes in frequency of herbicide detection and concentration do not appear related to changes in land use near sampled wells.

Mineralogy and the release of trace elements from slag from the Hegeler Zinc smelter, Illinois (USA)

USGS Publications Warehouse

Piatak, Nadine M.; Seal, Robert R.

2010-01-01

Slag from the former Hegeler Zn-smelting facility in Illinois (USA) is mainly composed of spinifex Ca-rich plagioclase, fine-grained dendritic or coarse-grained subhedral to anhedral clinopyroxenes, euhedral to subhedral spinels, spherical blebs of Fe sulfides, silicate glass, and less commonly fayalitic olivine. Mullite and quartz were also identified in one sample as representing remnants of the furnace lining. Secondary phases such as goethite, hematite and gypsum are significant in some samples and reflect surficial weathering of the dump piles or represent byproducts of roasting. A relatively rare Zn-rich material contains anhedral willemite, subhedral gahnite, massive zincite, hardystonite and a Zn sulfate (brianyoungite), among other phases, and likely represents the molten content of the smelting furnace before Zn extraction. The bulk major-element chemistry of most slag samples is dominated by SiO2, Al2O3, Fe2O3 and CaO. The bulk composition of the slag suggests a high viscosity of the melt and the mineralogy suggests a high silica content of the melt. Bulk slag trace-element chemistry shows that the dominant metal is Zn with >28.4 wt.% in the Zn-rich material and between 212 and 14,900 mg/kg in the other slags. The concentrations of other trace elements reach the following: 45 mg/kg As, 1170 mg/kg Ba, 191 mg/kg Cd, 242 mg/kg Co, 103 mg/kg Cr, 6360 mg/kg Cu, 107 mg/kg Ni, and 711 mg/kg Pb.Zinc, as the dominant metal in the slags, is likely the most environmentally significant metal in these samples; Cd, Cu, and Pb are also of concern and their concentrations exceed US Environmental Protection Agency preliminary remediation goals for residential soils. Spinel was found to be the dominant concentrator of Zn for samples containing significant Zn (>1 wt.%); the silicate glass also contained relatively high concentrations of Zn compared to other phases. Zinc partitioned into the silicates and oxides in these samples is generally more resistant to weathering and therefore less leached when compared to the slag samples with lower bulk Zn concentrations where Zn is likely partitioned into volumetrically minor sulfides. This is confirmed by leachate tests that resulted in low leachate Zn concentrations for samples with Zn partitioned into spinel. In contrast, the concentrations of Zn and SO4 are close to those expected from the dissolution of stoichiometric ZnS in leachates from samples in which the dominant host of Zn is suspected to be sulfides. The fact that Zn and other metals occur commonly as sulfides, which are more reactive than the silicates and oxides into which they dominantly partition according to other slag studies, indicates the Hegeler slag pile may be more of an environmental concern than other slag piles.

Observation of residues in tissues of chickens exposed to low dietary concentrations of chloramphenicol.

PubMed

Rejtharová, Martina; Rejthar, Libor; Čačková, Katarína; Bureš, Jiří; Vernerová, Eva; Hera, Alfred

2017-04-01

To investigate potential residues in tissues arising from naturally occurring low levels of chloramphenicol in plant material, feeding studies were conducted with chickens. A common chicken feed was prepared containing 0, 10, 50 and 200 μg kg -1 chloramphenicol and levels were confirmed by LC-MS/MS. Four separate groups of broiler chickens, eight animals in each group, were fed all their 35-day life with this contaminated feed. They were allowed ad libitum access to this feed and fresh water. After slaughtering the chickens, the residues in muscle and liver tissues were determined using GC/MS-NCI method. No residues were detected in tissues of animals from groups fed with feed containing 0, 10 or 50 µg kg -1 . Low chloramphenicol residual concentrations were observed in a few of the muscle samples obtained from the group of chickens fed with feed containing chloramphenicol in added concentration 200 µg kg -1 . No residues were detected in the remaining samples of this group. These results indicate that when residues of chloramphenicol are detected it is in all probability through illegal use.

Validation of an automated fluorescein method for determining bromide in water

USGS Publications Warehouse

Fishman, M. J.; Schroder, L.J.; Friedman, L.C.

1985-01-01

Surface, atmospheric precipitation and deionized water samples were spiked with ??g l-1 concentrations of bromide, and the solutions stored in polyethylene and polytetrafluoroethylene bottles. Bromide was determined periodically for 30 days. Automated fluorescein and ion chromatography methods were used to determine bromide in these prepared samples. Analysis of the data by the paired t-test indicates that the two methods are not significantly different at a probability of 95% for samples containing from 0.015 to 0.5 mg l-1 of bromide. The correlation coefficient for the same sets of paired data is 0.9987. Recovery data, except for the surface water samples to which 0.005 mg l-1 of bromide was added, range from 89 to 112%. There appears to be no loss of bromide from solution in either type of container.Surface, atmospheric precipitation and deionized water samples were spiked with mu g l** minus **1 concentrations of bromide, and the solutions stored in polyethylene and polytetrafluoroethylene bottles. Bromide was determined periodically for 30 days. Automated fluorescein and ion chromatography methods were used to determine bromide in these prepared samples. Analysis of the data by the paired t-test indicates that the two methods are not significantly different at a probability of 95% for samples containing from 0. 015 to 0. 5 mg l** minus **1 of bromide. The correlation coefficient for the same sets of paired data is 0. 9987. Recovery data, except for the surface water samples to which 0. 005 mg l** minus **1 of bromide was added, range from 89 to 112%. Refs.

Argonne Geothermal Geochemical Database v2.0

DOE Data Explorer

Harto, Christopher

2013-05-22

A database of geochemical data from potential geothermal sources aggregated from multiple sources as of March 2010. The database contains fields for the location, depth, temperature, pH, total dissolved solids concentration, chemical composition, and date of sampling. A separate tab contains data on non-condensible gas compositions. The database contains records for over 50,000 wells, although many entries are incomplete. Current versions of source documentation are listed in the dataset.

The use of Vacutainer tubes for collection of soil samples for helium analysis

USGS Publications Warehouse

Hinkle, Margaret E.; Kilburn, James E.

1979-01-01

Measurements of the helium concentration of soil samples collected and stored in Vacutainer-brand evacuated glass tubes show that Vacutainers are reliable containers for soil collection. Within the limits of reproducibility, helium content of soils appears to be independent of variations in soil temperature, barometric pressure, and quantity of soil moisture present in the sample.

An assessment of nonpoint-source discharges, streamflow, and water quality in Onion River, Wisconsin

USGS Publications Warehouse

Field, S.J.; Lidwin, R.A.

1984-01-01

All samples at both Hingham and Sheboygan Falls contained concentrations of un-ionized ammonia that were less than the U.S. Environmental Protection Agency's criteria (0.02 milligrams per liter), except the March 1980 samples. No samples exceeded the Wisconsin Department of Natural Resources criteria for un-ionized ammonia (0.04 milligrams per liter).

A method for direct, semi-quantitative analysis of gas phase samples using gas chromatography-inductively coupled plasma-mass spectrometry

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

Carter, Kimberly E; Gerdes, Kirk

2013-07-01

A new and complete GC–ICP-MS method is described for direct analysis of trace metals in a gas phase process stream. The proposed method is derived from standard analytical procedures developed for ICP-MS, which are regularly exercised in standard ICP-MS laboratories. In order to implement the method, a series of empirical factors were generated to calibrate detector response with respect to a known concentration of an internal standard analyte. Calibrated responses are ultimately used to determine the concentration of metal analytes in a gas stream using a semi-quantitative algorithm. The method was verified using a traditional gas injection from a GCmore » sampling valve and a standard gas mixture containing either a 1 ppm Xe + Kr mix with helium balance or 100 ppm Xe with helium balance. Data collected for Xe and Kr gas analytes revealed that agreement of 6–20% with the actual concentration can be expected for various experimental conditions. To demonstrate the method using a relevant “unknown” gas mixture, experiments were performed for continuous 4 and 7 hour periods using a Hg-containing sample gas that was co-introduced into the GC sample loop with the xenon gas standard. System performance and detector response to the dilute concentration of the internal standard were pre-determined, which allowed semi-quantitative evaluation of the analyte. The calculated analyte concentrations varied during the course of the 4 hour experiment, particularly during the first hour of the analysis where the actual Hg concentration was under predicted by up to 72%. Calculated concentration improved to within 30–60% for data collected after the first hour of the experiment. Similar results were seen during the 7 hour test with the deviation from the actual concentration being 11–81% during the first hour and then decreasing for the remaining period. The method detection limit (MDL) was determined for the mercury by injecting the sample gas into the system following a period of equilibration. The MDL for Hg was calculated as 6.8 μg · m -3. This work describes the first complete GC–ICP-MS method to directly analyze gas phase samples, and detailed sample calculations and comparisons to conventional ICP-MS methods are provided.« less

Rural drinking water at supply and household levels: quality and management.

PubMed

Hoque, Bilqis A; Hallman, Kelly; Levy, Jason; Bouis, Howarth; Ali, Nahid; Khan, Feroze; Khanam, Sufia; Kabir, Mamun; Hossain, Sanower; Shah Alam, Mohammad

2006-09-01

Access to safe drinking water has been an important national goal in Bangladesh and other developing countries. While Bangladesh has almost achieved accepted bacteriological drinking water standards for water supply, high rates of diarrheal disease morbidity indicate that pathogen transmission continues through water supply chain (and other modes). This paper investigates the association between water quality and selected management practices by users at both the supply and household levels in rural Bangladesh. Two hundred and seventy tube-well water samples and 300 water samples from household storage containers were tested for fecal coliform (FC) concentrations over three surveys (during different seasons). The tube-well water samples were tested for arsenic concentration during the first survey. Overall, the FC was low (the median value ranged from 0 to 4 cfu/100ml) in water at the supply point (tube-well water samples) but significantly higher in water samples stored in households. At the supply point, 61% of tube-well water samples met the Bangladesh and WHO standards of FC; however, only 37% of stored water samples met the standards during the first survey. When arsenic contamination was also taken into account, only 52% of the samples met both the minimum microbiological and arsenic content standards of safety. The contamination rate for water samples from covered household storage containers was significantly lower than that of uncovered containers. The rate of water contamination in storage containers was highest during the February-May period. It is shown that safe drinking water was achieved by a combination of a protected and high quality source at the initial point and maintaining quality from the initial supply (source) point through to final consumption. It is recommended that the government and other relevant actors in Bangladesh establish a comprehensive drinking water system that integrates water supply, quality, handling and related educational programs in order to ensure the safety of drinking water supplies.

Ambient water quality in aquifers used for drinking-water supplies, Gem County, southwestern Idaho, 2015

USGS Publications Warehouse

Bartolino, James R.; Hopkins, Candice B.

2016-12-20

In recent years, the rapid population growth in Gem County, Idaho, has been similar to other counties in southwestern Idaho, increasing about 54 percent from 1990 to 2015. Because the entire population of the study area depends on groundwater for drinking water supply (either from self-supplied domestic, community, or municipal-supply wells), this population growth, along with changes in land use (including potential petroleum exploration and development), indicated to the public and local officials the need to assess the quality of groundwater used for human consumption. To this end, the U.S. Geological Survey, in cooperation with Gem County and the Idaho Department of Environmental Quality, assessed the quality of groundwater from freshwater aquifers used for domestic supply in Gem County. A total of 47 domestic or municipal wells, 1 spring, and 2 surface-water sites on the Payette River were sampled during September 8–November 19, 2015. The sampled water was analyzed for a variety of constituents, including major ions, trace elements, nutrients, bacteria, radionuclides, dissolved gasses, stable isotopes of water and methane, and either volatile organic compounds (VOCs) or pesticides.To better understand analytical results, a conceptual hydrogeologic framework was developed in which three hydrogeologic units were described: Quaternary-Tertiary deposits (QTd), Tertiary Idaho Group rocks (Tig), and Tertiary-Cretaceous igneous rocks (TKi). Water levels were measured in 30 wells during sampling, and a groundwater-level altitude map was constructed for the QTd and Tig units showing groundwater flow toward the Emmett Valley and Payette River.Analytical results indicate that groundwater in Gem County is generally of good quality. Samples collected from two wells contained water with fluoride concentrations greater than the U.S. Environmental Protection Agency (EPA) Maximum Contaminant Level (MCL) of 4 milligrams per liter (mg/L), six wells contained arsenic at concentrations greater than the EPA MCL of 10 micrograms per liter, and a sample from one well exceeded the MCL of 15 picocuries per liter for alpha particles. Although previous samples collected from some wells in Gem County contained nitrate concentrations greater than the MCL of 10 mg/L, the largest concentration detected in the current study was 5.2 mg/L. Total coliform bacteria was detected in four groundwater samples.Three volatile organic compounds (VOCs) were detected in samples collected from five wells, and five compounds of the triazine class of herbicides were detected in samples from five wells; no concentrations were greater than applicable EPA MCLs. Methane was detected in samples from 36 wells, with the concentration in 1 well large enough to be considered an explosion hazard by U.S. Office of Surface Mining guidelines. Stable isotope signatures of methane in six samples suggest that naturally occurring methane in Gem County is probably of both thermogenic and biogenic origin.

Continuous monitoring of L-glutamate released from cultured nerve cells by an online sensor coupled with micro-capillary sampling.

PubMed

Niwa, O; Horiuchi, T; Torimitsu, K

1997-01-01

A small volume L-glutamate online sensor was developed in order to monitor changes in the local concentration of L-glutamate released from cultured nerve cells. Syringe pump in the suction mode is used to sample extracellular fluid continuously from a glass micro-capillary and the concentration of L-glutamate can be determined by using a glassy carbon (GC) electrode modified with an Os-polyvinylpyridine mediator bottom film containing horseradish peroxidase and a bovine serum albumin top layer containing L-glutamate oxidase. The overall efficiency of L-glutamate detection with a sensor is 71% under optimum conditions due to an efficient enzymatic reaction at the modified electrode in the thin layer radial flow cell. As a result, we achieved a detection limit of 7-15 nM and a linear range of 50 nM to 10 microM. In an in vitro experiment, the extracellular fluid near a particular nerve cell can be sampled with this micro-pipet and continuously introduced into the modified GC electrode in the radial flow cell via suction provided by a syringe pump. The nerve cells are stimulated by the KCl in a glass capillary and the L-glutamate concentration change can be monitored by changing the distance between the sampling pipet and the nerve cells.

Characterization of long-term elution of platinum from carboplatin-impregnated calcium sulfate hemihydrate beads in vitro by two distinct sample collection methods.

PubMed

Tulipan, Rachel J; Phillips, Heidi; Garrett, Laura D; Dirikolu, Levent; Mitchell, Mark A

2017-05-01

OBJECTIVE To characterize long-term elution of platinum from carboplatin-impregnated calcium sulfate hemihydrate (CI-CSH) beads in vitro by comparing 2 distinct sample collection methods designed to mimic 2 in vivo environments. SAMPLES 162 CI-CSH beads containing 4.6 mg of carboplatin (2.4 mg of platinum/bead). PROCEDURES For method 1, which mimicked an in vivo environment with rapid and complete fluid exchange, each of 3 plastic 10-mL conical tubes contained 3 CI-CSH beads and 5 mL of PBS solution. Eluent samples were obtained by evacuation of all fluid at 1, 2, 3, 6, 9, and 12 hours and 1, 2, 3, 6, 9, 12, 15, 18, 22, 26, and 30 days. Five milliliters of fresh PBS solution was then added to each tube. For method 2, which mimicked an in vivo environment with no fluid exchange, each of 51 tubes (ie, 3 tubes/17 sample collection times) contained 3 CI-CSH beads and 5 mL of PBS solution. Eluent samples were obtained from the assigned tubes for each time point. All samples were analyzed for platinum content by inductively coupled plasma-mass spectrometry. RESULTS Platinum was released from CI-CSH beads for 22 to 30 days. Significant differences were found in platinum concentration and percentage of platinum eluted from CI-CSH beads over time for each method. Platinum concentrations and elution percentages in method 2 samples were significantly higher than those of method 1 samples, except for the first hour measurements. CONCLUSIONS AND CLINICAL RELEVANCE Sample collection methods 1 and 2 may provide estimates of the minimum and maximum platinum release, respectively, from CI-CSH beads in vivo.

Toxic metals in ayurvedic preparations from a public health lead poisoning cluster investigation.

PubMed

Mikulski, Marek A; Wichman, Michael D; Simmons, Donald L; Pham, Anthony N; Clottey, Valentina; Fuortes, Laurence J

2017-07-01

Background Herbal formulations, traditional medicine, and complementary and alternative medicine are used by the majority of the world's population. Toxicity associated with use of Ayurvedic products due to metal content is an increasingly recognized potential public health problem. Objectives Report on toxic metals content of Ayurvedic products obtained during an investigation of lead poisoning among users of Ayurvedic medicine. Methods Samples of Ayurvedic formulations were analyzed for metals and metalloids following established US. Environmental Protection Agency methods. Results Lead was found in 65% of 252 Ayurvedic medicine samples with mercury and arsenic found in 38 and 32% of samples, respectively. Almost half of samples containing mercury, 36% of samples containing lead and 39% of samples containing arsenic had concentrations of those metals per pill that exceeded, up to several thousand times, the recommended daily intake values for pharmaceutical impurities. Conclusions Lack of regulations regarding manufacturing and content or purity of Ayurvedic and other herbal formulations poses a significant global public health problem.

Widespread Use and Frequent Detection of Neonicotinoid Insecticides in Wetlands of Canada's Prairie Pothole Region

PubMed Central

Main, Anson R.; Headley, John V.; Peru, Kerry M.; Michel, Nicole L.; Cessna, Allan J.; Morrissey, Christy A.

2014-01-01

Neonicotinoids currently dominate the insecticide market as seed treatments on Canada's major Prairie crops (e.g., canola). The potential impact to ecologically significant wetlands in this dominantly agro-environment has largely been overlooked while the distribution of use, incidence and level of contamination remains unreported. We modelled the spatial distribution of neonicotinoid use across the three Prairie Provinces in combination with temporal assessments of water and sediment concentrations in wetlands to measure four active ingredients (clothianidin, thiamethoxam, imidacloprid and acetamiprid). From 2009 to 2012, neonicotinoid use was increasing; by 2012, applications covered an estimated ∼11 million hectares (44% of Prairie cropland) with >216,000 kg of active ingredients. Thiamethoxam, followed by clothianidin, were the dominant seed treatments by mass and area. Areas of high neonicotinoid use were identified as high density canola or soybean production. Water sampled four times from 136 wetlands (spring, summer, fall 2012 and spring 2013) across four rural municipalities in Saskatchewan similarly revealed clothianidin and thiamethoxam in the majority of samples. In spring 2012 prior to seeding, 36% of wetlands contained at least one neonicotinoid. Detections increased to 62% in summer 2012, declined to 16% in fall, and increased to 91% the following spring 2013 after ice-off. Peak concentrations were recorded during summer 2012 for both thiamethoxam (range:

Widespread use and frequent detection of neonicotinoid insecticides in wetlands of Canada's Prairie Pothole Region.

PubMed

Main, Anson R; Headley, John V; Peru, Kerry M; Michel, Nicole L; Cessna, Allan J; Morrissey, Christy A

2014-01-01

Neonicotinoids currently dominate the insecticide market as seed treatments on Canada's major Prairie crops (e.g., canola). The potential impact to ecologically significant wetlands in this dominantly agro-environment has largely been overlooked while the distribution of use, incidence and level of contamination remains unreported. We modelled the spatial distribution of neonicotinoid use across the three Prairie Provinces in combination with temporal assessments of water and sediment concentrations in wetlands to measure four active ingredients (clothianidin, thiamethoxam, imidacloprid and acetamiprid). From 2009 to 2012, neonicotinoid use was increasing; by 2012, applications covered an estimated ∼11 million hectares (44% of Prairie cropland) with >216,000 kg of active ingredients. Thiamethoxam, followed by clothianidin, were the dominant seed treatments by mass and area. Areas of high neonicotinoid use were identified as high density canola or soybean production. Water sampled four times from 136 wetlands (spring, summer, fall 2012 and spring 2013) across four rural municipalities in Saskatchewan similarly revealed clothianidin and thiamethoxam in the majority of samples. In spring 2012 prior to seeding, 36% of wetlands contained at least one neonicotinoid. Detections increased to 62% in summer 2012, declined to 16% in fall, and increased to 91% the following spring 2013 after ice-off. Peak concentrations were recorded during summer 2012 for both thiamethoxam (range:

Arsenic contamination of groundwater and its health impact on residents in a village in West Bengal, India.

PubMed Central

Rahman, Mohammad Mahmudur; Sengupta, Mrinal Kumar; Ahamed, Sad; Chowdhury, Uttam Kumar; Lodh, Dilip; Hossain, Amir; Das, Bhaskar; Roy, Niladri; Saha, Kshitish Chandra; Palit, Shyamal Kanti; Chakraborti, Dipankar

2005-01-01

An in-depth study was carried out in Rajapur, an arsenic-affected village in West Bengal, India, to determine the degree of groundwater contamination with arsenic and the impact of this contamination on residents. The flow injection hydride generation atomic absorption spectrometry (FI-HG-AAS) method was used to measure arsenic concentrations in water and biological samples. Dermatologists recorded the dermatological features of arsenicosis. Out of a total of 336 hand-pumped tube-wells in Rajapur, 91% (307/336) contained arsenic at concentrations > 10 microg/l, and 63% (213/336) contained arsenic at > 50 microg/l. The type of arsenic in groundwater, the variation in concentrations of arsenic as the depth of tube-wells changed, and the iron concentration in the wells were also measured. Altogether 825 of 3500 residents were examined for skin lesions; of these, 149 had lesions caused by exposure to arsenic. Of the 420 biological samples collected and analysed, 92.6% (389) contained arsenic at concentrations that were above normal. Thus many villagers might be subclinically affected. Although five arsenic-filtering devices had been installed in Rajapur, it appears that villagers are still exposed to raised concentrations of arsenic in their drinking-water. Detailed village-level studies of arsenic-affected areas in West Bengal are required in order to understand the magnitude of contamination and its effects on people. Villagers are ill-informed about the dangers of drinking arsenic-contaminated water. The contamination could be brought under control by increasing community awareness of the dangers and implementing proper watershed management techniques that involve local people. PMID:15682249

Effects of oral administration of a commercial activated charcoal suspension on serum osmolality and lactate concentration in the dog.

PubMed

Burkitt, Jamie M; Haskins, Steve C; Aldrich, Janet; Jandrey, Karl E; Rezende, Marlis L; Boyle, Jennifer E

2005-01-01

The purpose of this investigation was to determine the effects of an activated charcoal (AC) suspension containing propylene glycol and glycerol on serum osmolality, osmolal gap, and lactate concentration in dogs. Six healthy adult dogs were administered 4 g/kg AC in a commercially available suspension that contained propylene glycol and glycerol as vehicles. Blood samples were taken before and 1, 4, 6, 8, 12, and 24 hours after the administration of the test suspension. Samples were analyzed for osmolality, blood gases, and concentrations of lactate, sodium, potassium, serum urea nitrogen, and glucose. Osmolal gaps were calculated for each time point. Mean serum osmolality, osmolal gap, and lactate concentration were significantly increased after suspension administration compared to baseline. Serum osmolality increased from 311 mOsm/kg at baseline to 353 mOsm/kg, osmolal gap increased from 5 to 52 mOsm/kg, and lactate concentration increased from 1.9 to 4.5 mmol/L after suspension administration (all P < .01). Three of the 6 dogs vomited between 1 and 3 hours after the administration of the test suspension, and 4 of 6 dogs were lethargic. All dogs drank frequently after AC administration. Commercial AC suspension administered at a clinically relevant dose increases serum osmolality, osmolal gap, and lactate concentration in dogs. These laboratory measures and the clinical signs of vomiting, lethargy, and increased frequency of drinking might complicate the diagnosis or monitoring of some intoxications (such as ethylene glycol) in dogs that have previously received AC suspension containing propylene glycol, glycerol, or both as vehicles.

Stabilization of sulfuric acid dimers by ammonia, methylamine, dimethylamine, and trimethylamine

NASA Astrophysics Data System (ADS)

Jen, Coty N.; McMurry, Peter H.; Hanson, David R.

2014-06-01

This study experimentally explores how ammonia (NH3), methylamine (MA), dimethylamine (DMA), and trimethylamine (TMA) affect the chemical formation mechanisms of electrically neutral clusters that contain two sulfuric acid molecules (dimers). Dimers may also contain undetectable compounds, such as water or bases, that evaporate upon ionization and sampling. Measurements were conducted using a glass flow reactor which contained a steady flow of humidified nitrogen with sulfuric acid concentrations of 107 to 109 cm-3. A known molar flow rate of a basic gas was injected into the flow reactor. The University of Minnesota Cluster Chemical Ionization Mass Spectrometer was used to measure the resulting sulfuric acid vapor and cluster concentrations. It was found that, for a given concentration of sulfuric acid vapor, the dimer concentration increases with increasing concentration of the basic gas, eventually reaching a plateau. The base concentrations at which the dimer concentrations saturate suggest NH3 < MA < TMA ≲ DMA in forming stabilized sulfuric acid dimers. Two heuristic models for cluster formation by acid-base reactions are developed to interpret the data. The models provide ranges of evaporation rate constants that are consistent with observations and leads to an analytic expression for nucleation rates that is consistent with atmospheric observations.

Miniature Laboratory for Detecting Sparse Biomolecules

NASA Technical Reports Server (NTRS)

Lin, Ying; Yu, Nan

2005-01-01

A miniature laboratory system has been proposed for use in the field to detect sparsely distributed biomolecules. By emphasizing concentration and sorting of specimens prior to detection, the underlying system concept would make it possible to attain high detection sensitivities without the need to develop ever more sensitive biosensors. The original purpose of the proposal is to aid the search for signs of life on a remote planet by enabling the detection of specimens as sparse as a few molecules or microbes in a large amount of soil, dust, rocks, water/ice, or other raw sample material. Some version of the system could prove useful on Earth for remote sensing of biological contamination, including agents of biological warfare. Processing in this system would begin with dissolution of the raw sample material in a sample-separation vessel. The solution in the vessel would contain floating microscopic magnetic beads coated with substances that could engage in chemical reactions with various target functional groups that are parts of target molecules. The chemical reactions would cause the targeted molecules to be captured on the surfaces of the beads. By use of a controlled magnetic field, the beads would be concentrated in a specified location in the vessel. Once the beads were thus concentrated, the rest of the solution would be discarded. This procedure would obviate the filtration steps and thereby also eliminate the filter-clogging difficulties of typical prior sample-concentration schemes. For ferrous dust/soil samples, the dissolution would be done first in a separate vessel before the solution is transferred to the microbead-containing vessel.

Resuspension of ash after the 2014 phreatic eruption at Ontake volcano, Japan

NASA Astrophysics Data System (ADS)

Miwa, Takahiro; Nagai, Masashi; Kawaguchi, Ryohei

2018-02-01

We determined the resuspension process of an ash deposit after the phreatic eruption of September 27th, 2014 at Ontake volcano, Japan, by analyzing the time series data of particle concentrations obtained using an optical particle counter and the characteristics of an ash sample. The time series of particle concentration was obtained by an optical particle counter installed 11 km from the volcano from September 21st to October 19th, 2014. The time series contains counts of dust particles (ash and soil), pollen, and water drops, and was corrected to calculate the concentration of dust particles based on a polarization factor reflecting the optical anisotropy of particles. The dust concentration was compared with the time series of wind velocity. The dust concentration was high and the correlation coefficient with wind velocity was positive from September 28th to October 2nd. Grain-size analysis of an ash sample confirmed that the ash deposit contains abundant very fine particles (< 30 μm). Simple theoretical calculations revealed that the daily peaks of the moderate wind (a few m/s at 10 m above the ground surface) were comparable with the threshold wind velocity for resuspension of an unconsolidated deposit with a wide range of particle densities. These results demonstrate that moderate wind drove the resuspension of an ash deposit containing abundant fine particles produced by the phreatic eruption. Histogram of polarization factors of each species experimentally obtained. The N is the number of analyzed particles.

Screening of ground water samples for volatile organic compounds using a portable gas chromatograph

USGS Publications Warehouse

Buchmiller, R.C.

1989-01-01

A portable gas chromatograph was used to screen 32 ground water samples for volatile organic compounds. Seven screened samples were positive; four of the seven samples had volatile organic substances identified by second-column confirmation. Four of the seven positive, screened samples also tested positive in laboratory analyses of duplicate samples. No volatile organic compounds were detected in laboratory analyses of samples that headspace screening indicated to be negative. Samples that contained volatile organic compounds, as identified by laboratory analysis, and that contained a volatile organic compound present in a standard of selected compounds were correctly identified by using the portable gas chromatography. Comparisons of screened-sample data with laboratory data indicate the ability to detect selected volatile organic compounds at concentrations of about 1 microgram per liter in the headspace of water samples by use of a portable gas chromatography. -Author

Concentration and purification of HIV-1 virions by microfluidic separation of superparamagnetic nanoparticles

PubMed Central

Chen, Grace Dongqing; Alberts, Catharina Johanna

2009-01-01

The low concentration and complex sample matrix of many clinical and environmental viral samples presents a significant challenge in the development of low cost, point-of-care viral assays. To address this problem, we investigated the use of a microfluidic passive magnetic separator combined with on-chip mixer to both purify and concentrate whole particle HIV-1 virions. Virus-containing plasma samples are first mixed to allow specific binding of the viral particles with antibody-conjugated superparamagnetic nanoparticles, and several passive mixer geometries were assessed for their mixing efficiencies. The virus-nanoparticle complexes are then separated from the plasma in a novel magnetic separation chamber, where packed micron-sized ferromagnetic particles serve as high magnetic gradient concentrators for an externally applied magnetic field. Thereafter, a viral lysis buffer was flowed through the chip and the released HIV proteins were assayed off-chip. Viral protein extraction efficiencies of 62% and 45% were achieved at 10uL/min and 30uL/min throughputs respectively. More importantly, an 80-fold concentration was observed for an initial sample volume of 1mL, and a 44-fold concentration for an initial sample volume of 0.5mL. The system is broadly applicable to microscale sample preparation of any viral sample and can be used for nucleic acid extraction as well as 40–80 fold enrichment of target viruses. PMID:19954210

Measuring factor IX activity of nonacog beta pegol with commercially available one-stage clotting and chromogenic assay kits: a two-center study.

PubMed

Bowyer, A E; Hillarp, A; Ezban, M; Persson, P; Kitchen, S

2016-07-01

Essentials Validated assays are required to precisely measure factor IX (FIX) activity in FIX products. N9-GP and two other FIX products were assessed in various coagulation assay systems at two sites. Large variations in FIX activity measurements were observed for N9-GP using some assays. One-stage and chromogenic assays accurately measuring FIX activity for N9-GP were identified. Background Measurement of factor IX activity (FIX:C) with activated partial thromboplastin time-based one-stage clotting assays is associated with a large degree of interlaboratory variation in samples containing glycoPEGylated recombinant FIX (rFIX), i.e. nonacog beta pegol (N9-GP). Validation and qualification of specific assays and conditions are necessary for the accurate assessment of FIX:C in samples containing N9-GP. Objectives To assess the accuracy of various one-stage clotting and chromogenic assays for measuring FIX:C in samples containing N9-GP as compared with samples containing rFIX or plasma-derived FIX (pdFIX) across two laboratory sites. Methods FIX:C, in severe hemophilia B plasma spiked with a range of concentrations (from very low, i.e. 0.03 IU mL(-1) , to high, i.e. 0.90 IU mL(-1) ) of N9-GP, rFIX (BeneFIX), and pdFIX (Mononine), was determined at two laboratory sites with 10 commercially available one-stage clotting assays and two chromogenic FIX:C assays. Assays were performed with a plasma calibrator and different analyzers. Results A high degree of variation in FIX:C measurement was observed for one-stage clotting assays for N9-GP as compared with rFIX or pdFIX. Acceptable N9-GP recovery was observed in the low-concentration to high-concentration samples tested with one-stage clotting assays using SynthAFax or DG Synth, or with chromogenic FIX:C assays. Similar patterns of FIX:C measurement were observed at both laboratory sites, with minor differences probably being attributable to the use of different analyzers. Conclusions These results suggest that, of the reagents tested, FIX:C in N9-GP-containing plasma samples can be most accurately measured with one-stage clotting assays using SynthAFax or DG Synth, or with chromogenic FIX:C assays. © 2016 International Society on Thrombosis and Haemostasis.

Improvement of immunoassay detection system by using alternating current magnetic susceptibility

NASA Astrophysics Data System (ADS)

Kawabata, R.; Mizoguchi, T.; Kandori, A.

2016-03-01

A major goal with this research was to develop a low-cost and highly sensitive immunoassay detection system by using alternating current (AC) magnetic susceptibility. We fabricated an improved prototype of our previously developed immunoassay detection system and evaluated its performance. The prototype continuously moved sample containers by using a magnetically shielded brushless motor, which passes between two anisotropic magneto resistance (AMR) sensors. These sensors detected the magnetic signal in the direction where each sample container passed them. We used the differential signal obtained from each AMR sensor's output to improve the signal-to-noise ratio (SNR) of the magnetic signal measurement. Biotin-conjugated polymer beads with avidin-coated magnetic particles were prepared to examine the calibration curve, which represents the relation between AC magnetic susceptibility change and polymer-bead concentration. For the calibration curve measurement, we, respectively, measured the magnetic signal caused by the magnetic particles by using each AMR sensor installed near the upper or lower part in the lateral position of the passing sample containers. As a result, the SNR of the prototype was 4.5 times better than that of our previous system. Moreover, the data obtained from each AMR sensor installed near the upper part in the lateral position of the passing sample containers exhibited an accurate calibration curve that represented good correlation between AC magnetic susceptibility change and polymer-bead concentration. The conclusion drawn from these findings is that our improved immunoassay detection system will enable a low-cost and highly sensitive immunoassay.

Improvement of immunoassay detection system by using alternating current magnetic susceptibility.

PubMed

Kawabata, R; Mizoguchi, T; Kandori, A

2016-03-01

A major goal with this research was to develop a low-cost and highly sensitive immunoassay detection system by using alternating current (AC) magnetic susceptibility. We fabricated an improved prototype of our previously developed immunoassay detection system and evaluated its performance. The prototype continuously moved sample containers by using a magnetically shielded brushless motor, which passes between two anisotropic magneto resistance (AMR) sensors. These sensors detected the magnetic signal in the direction where each sample container passed them. We used the differential signal obtained from each AMR sensor's output to improve the signal-to-noise ratio (SNR) of the magnetic signal measurement. Biotin-conjugated polymer beads with avidin-coated magnetic particles were prepared to examine the calibration curve, which represents the relation between AC magnetic susceptibility change and polymer-bead concentration. For the calibration curve measurement, we, respectively, measured the magnetic signal caused by the magnetic particles by using each AMR sensor installed near the upper or lower part in the lateral position of the passing sample containers. As a result, the SNR of the prototype was 4.5 times better than that of our previous system. Moreover, the data obtained from each AMR sensor installed near the upper part in the lateral position of the passing sample containers exhibited an accurate calibration curve that represented good correlation between AC magnetic susceptibility change and polymer-bead concentration. The conclusion drawn from these findings is that our improved immunoassay detection system will enable a low-cost and highly sensitive immunoassay.

3H/3He age data in assessing the susceptibility of wells to contamination

USGS Publications Warehouse

Manning, Andrew H.; Solomon, D. Kip; Thiros, Susan A.

2005-01-01

Regulatory agencies are becoming increasingly interested in using young–ground water dating techniques, such as the 3H/3He method, in assessing the susceptibility of public supply wells (PSWs) to contamination. However, recent studies emphasize that ground water samples of mixed age may be the norm, particularly from long-screened PSWs, and tracer-based “apparent” ages can differ substantially from actual mean ages for mixed-age samples. We present age and contaminant data from PSWs in Salt Lake Valley, Utah, that demonstrate the utility of 3H and 3He measurements in evaluating well susceptibility, despite potential age mixing. Initial 3H concentrations (measured 3H + measured tritiogenic 3He) are compared to those expected based on the apparent 3H/3He age and the local precipitation 3H record. This comparison is used to determine the amount of modern water (recharged after ∼1950) vs. prebomb water (recharged before ∼1950) samples might contain. Concentrations of common contaminants were also measured using detection limits generally lower than those used for regulatory purposes. A clear correlation exists between the potential magnitude of the modern water fraction and both the occurrence and concentration of contaminants. For samples containing dominantly modern water based on their initial 3H concentrations, potential discrepancies between apparent 3H/3He ages and mean ages are explored using synthetic samples that are random mixtures of different modern waters. Apparent ages can exceed mean ages by up to 13 years for these samples, with an exponential age distribution resulting in the greatest discrepancies.

Leaching, transport, and methylation of mercury in and around abandoned mercury mines in the Humboldt River basin and surrounding areas, Nevada. Chapter C.

USGS Publications Warehouse

Gray, John E.; Stillings, Lisa L.

2003-01-01

Mercury and methylmercury concentrations were measured in mine wastes, stream sediments, and stream waters collected both proximal and distal from abandoned mercury mines to evaluate mercury contamination and mercury methylation in the Humboldt River system. The climate in the study area is arid, and due to the lack of mine-water runoff, water-leaching laboratory experiments were used to evaluate the potential of mine wastes to release mercury. Mine-waste calcine contains mercury concentrations as high as 14,000 ?g/g. Stream-sediment samples collected within 1 km of the mercury mines studied contain mercury concentrations as high as 170 ?g/g, but sediments collected from the Humboldt River and regional baseline sites have much lower mercury contents, less than 0.44 ?g/g. Similarly, methylmercury concentrations in mine-waste calcine are locally as high as 96 ng/g, but methylmercury contents in stream sediments collected down-stream from the mines and from the Humboldt River are lower (<0.05-0.95 ng/g). Stream-water samples collected below two mines studied contain mercury concentrations ranging from 6 to 2,000 ng/L, whereas mercury contents in Humboldt River and Rye Patch Reservoir water were generally lower, ranging from 2.1 to 9.0 ng/L. Methylmercury concentrations in Humboldt River system water were the lowest in this study (<0.02- 0.27 ng/L). Although mercury and methylmercury concentrations were elevated in some mine-waste calcine and mercury concentrations were locally high in mine-waste leachate samples, data show significant dilution of mercury and lower mercury methylation down gradient from the mines, especially in the sediments and water collected from the Humboldt River, which is more than 8 km from any mercury mines. Data show only minor, local transference of mercury and methylmercury from mine-waste calcine to stream sediment, and then onto the water column, and indicate little transference of mercury from the mine sites to the Humboldt River system.

High throughput liquid absorption preconcentrator sampling instrument

DOEpatents

Zaromb, Solomon; Bozen, Ralph M.

1992-01-01

A system for detecting trace concentrations of an analyte in air includes a preconcentrator for the analyte and an analyte detector. The preconcentrator includes an elongated tubular container comprising a wettable material. The wettable material is continuously wetted with an analyte-sorbing liquid which flows from one part of the container to a lower end. Sampled air flows through the container in contact with the wetted material with a swirling motion which results in efficient transfer of analyte vapors or aerosol particles to the sorbing liquid and preconcentration of traces of analyte in the liquid. The preconcentrated traces of analyte may be either detected within the container or removed therefrom for injection into a separate detection means or for subsequent analysis.

High-throughput liquid-absorption preconcentrator sampling methods

DOEpatents

Zaromb, Solomon

1994-01-01

A system for detecting trace concentrations of an analyte in air includes a preconcentrator for the analyte and an analyte detector. The preconcentrator includes an elongated tubular container comprising a wettable material. The wettable material is continuously wetted with an analyte-sorbing liquid which flows from one part of the container to a lower end. Sampled air flows through the container in contact with the wetted material with a swirling motion which results in efficient transfer of analyte vapors or aerosol particles to the sorbing liquid and preconcentration of traces of analyte in the liquid. The preconcentrated traces of analyte may be either detected within the container or removed therefrom for injection into a separate detection means or for subsequent analysis.

High throughput liquid absorption preconcentrator sampling instrument

DOEpatents

Zaromb, S.; Bozen, R.M.

1992-12-22

A system for detecting trace concentrations of an analyte in air includes a preconcentrator for the analyte and an analyte detector. The preconcentrator includes an elongated tubular container comprising a wettable material. The wettable material is continuously wetted with an analyte-sorbing liquid which flows from one part of the container to a lower end. Sampled air flows through the container in contact with the wetted material with a swirling motion which results in efficient transfer of analyte vapors or aerosol particles to the sorbing liquid and preconcentration of traces of analyte in the liquid. The preconcentrated traces of analyte may be either detected within the container or removed therefrom for injection into a separate detection means or for subsequent analysis. 12 figs.

High-throughput liquid-absorption preconcentrator sampling methods

DOEpatents

Zaromb, S.

1994-07-12

A system for detecting trace concentrations of an analyte in air includes a preconcentrator for the analyte and an analyte detector. The preconcentrator includes an elongated tubular container comprising a wettable material. The wettable material is continuously wetted with an analyte-sorbing liquid which flows from one part of the container to a lower end. Sampled air flows through the container in contact with the wetted material with a swirling motion which results in efficient transfer of analyte vapors or aerosol particles to the sorbing liquid and preconcentration of traces of analyte in the liquid. The preconcentrated traces of analyte may be either detected within the container or removed therefrom for injection into a separate detection means or for subsequent analysis. 12 figs.

Changes in sample collection and analytical techniques and effects on retrospective comparability of low-level concentrations of trace elements in ground water

USGS Publications Warehouse

Ivahnenko, T.; Szabo, Z.; Gibs, J.

2001-01-01

Ground-water sampling techniques were modified to reduce random low-level contamination during collection of filtered water samples for determination of trace-element concentrations. The modified sampling techniques were first used in New Jersey by the US Geological Survey in 1994 along with inductively coupled plasma-mass spectrometry (ICP-MS) analysis to determine the concentrations of 18 trace elements at the one microgram-per-liter (μg/L) level in the oxic water of the unconfined sand and gravel Kirkwood-Cohansey aquifer system. The revised technique tested included a combination of the following: collection of samples (1) with flow rates of about 2L per minute, (2) through acid-washed single-use disposable tubing and (3) a single-use disposable 0.45-μm pore size capsule filter, (4) contained within portable glove boxes, (5) in a dedicated clean sampling van, (6) only after turbidity stabilized at values less than 2 nephelometric turbidity units (NTU), when possible. Quality-assurance data, obtained from equipment blanks and split samples, indicated that trace element concentrations, with the exception of iron, chromium, aluminum, and zinc, measured in the samples collected in 1994 were not subject to random contamination at 1μg/L.Results from samples collected in 1994 were compared to those from samples collected in 1991 from the same 12 PVC-cased observation wells using the available sampling and analytical techniques at that time. Concentrations of copper, lead, manganese and zinc were statistically significantly lower in samples collected in 1994 than in 1991. Sampling techniques used in 1994 likely provided trace-element data that represented concentrations in the aquifer with less bias than data from 1991 when samples were collected without the same degree of attention to sample handling.

SEM/XPS analysis of fractured adhesively bonded graphite fibre-reinforced polyimide composites

NASA Technical Reports Server (NTRS)

Devilbiss, T. A.; Messick, D. L.; Wightman, J. P.; Progar, D. J.

1985-01-01

The surfaces of the graphite fiber-reinforced polyimide composites presently pretreated prior to bonding with polyimide adhesive contained variable amounts of a fluoropolymer, as determined by X-ray photoelectron spectroscopy. Lap shear strengths were determined for unaged samples and for those aged over 500- and 1000-hour periods at 177 and 232 C. Unaged sample lap strengths, which were the highest obtained, exhibited no variation with surface pretreatment, but a significant decrease is noted with increasing aging temperature. These thermally aged samples, however, had increased surface fluorine concentration, while a minimal concentration was found in unaged samples. SEM demonstrated a progressive shift from cohesive to adhesive failure for elevated temperature-aged composites.

Properties of protein powders from arrowtooth flounder (Atheresthes stomias) and herring (Clupea harengus) byproducts.

PubMed

Sathivel, Subramaniam; Bechtel, Peter J; Babbitt, Jerry; Prinyawiwatkul, Witoon; Negulescu, Ioan I; Reppond, Kermit D

2004-08-11

Functional, nutritional, and thermal properties of freeze-dried protein powders (FPP) from whole herring (WHP), herring body (HBP), herring head (HHP), herring gonad (HGP), and arrowtooth flounder fillets (AFP) were evaluated. The FPP samples have desirable nutritional and functional properties and contained 63-81.4% protein. All FPP samples had desirable essential amino acid profiles and mineral contents. The emulsifying and fat adsorption capacities of all FPP samples were higher than those of soy protein concentrate. The emulsifying stability of WHP was lower than that of egg albumin but greater than that of soy protein concentrate. Thermal stability of the FPP samples is in the following order: HGP > HBP > WHP > HHP > AFP.

Evaluation of National Atmospheric Deposition Program measurements for co-located Sites CO89 and CO98 at Rocky Mountain National Park, 2012

USGS Publications Warehouse

,

2013-01-01

Median weekly absolute percent differences for selected parameters including: sample volume, 8.0 percent; ammonium concentration, 9.1 percent; nitrate concentration, 8.5 percent; sulfate concentration, 10.2 percent. Annual precipitation-weighted mean concentrations were higher for CO98 compared to CO89 for all analytes. The chemical concentration record for CO98 contains more valid samples than the CO89 record. Therefore, the CO98 record is more representative of 2012 total annual deposition at Loch Vale. Daily precipitation-depth records for the co-located precipitation gages were 100 percent complete, and the total annual precipitation depths between the sites differed by 0.1 percent for the year (91.5 and 91.4 cm).

Botulinum Neurotoxins: Qualitative and Quantitative Analysis Using the Mouse Phrenic Nerve Hemidiaphragm Assay (MPN).

PubMed

Bigalke, Hans; Rummel, Andreas

2015-11-25

The historical method for the detection of botulinum neurotoxin (BoNT) is represented by the mouse bioassay (MBA) measuring the animal survival rate. Since the endpoint of the MBA is the death of the mice due to paralysis of the respiratory muscle, an ex vivo animal replacement method, called mouse phrenic nerve (MPN) assay, employs the isolated N. phrenicus-hemidiaphragm tissue. Here, BoNT causes a dose-dependent characteristic decrease of the contraction amplitude of the indirectly stimulated muscle. Within the EQuATox BoNT proficiency 13 test samples were analysed using the MPN assay by serial dilution to a bath concentration resulting in a paralysis time within the range of calibration curves generated with BoNT/A, B and E standards, respectively. For serotype identification the diluted samples were pre-incubated with polyclonal anti-BoNT/A, B or E antitoxin or a combination of each. All 13 samples were qualitatively correctly identified thereby delivering superior results compared to single in vitro methods like LFA, ELISA and LC-MS/MS. Having characterized the BoNT serotype, the final bath concentrations were calculated using the calibration curves and then multiplied by the respective dilution factor to obtain the sample concentration. Depending on the source of the BoNT standards used, the quantitation of ten BoNT/A containing samples delivered a mean z-score of 7 and of three BoNT/B or BoNT/E containing samples z-scores <2, respectively.

Radionuclides in ground water of the Carson River Basin, western Nevada and eastern California, U.S.A.

USGS Publications Warehouse

Thomas, J.M.; Welch, A.H.; Lico, M.S.; Hughes, J.L.; Whitney, R.

1993-01-01

Ground water is the main source of domestic and public supply in the Carson River Basin. Ground water originates as precipitation primarily in the Sierra Nevada in the western part of Carson and Eagle Valleys, and flows down gradient in the direction of the Carson River through Dayton and Churchill Valleys to a terminal sink in the Carson Desert. Because radionuclides dissolved in ground water can pose a threat to human health, the distribution and sources of several naturally occurring radionuclides that contribute to gross-alpha and gross-beta activities in the study area were investigated. Generally, alpha and beta activities and U concentration increase from the up-gradient to down-gradient hydrographic areas of the Carson River Basin, whereas 222Rn concentration decreases. Both 226Ra and 228Ra concentrations are similar throughout the study area. Alpha and beta activities and U concentration commonly exceed 100 pCi/l in the Carson Desert at the distal end of the flow system. Radon-222 commonly exceeds 2,000 pCi/l in the western part of Carson and Eagle Valleys adjacent to the Sierra Nevada. Radium-226 and 228Ra concentrations are <5 pCi/l. Four ground water samples were analyzed for 210Po and one sample contained a high concentration of 21 pCi/l. Seven samples were analyzed for 210Pb; six contained <3 pCi/l and one contained 12 pCi/l. Thorium-230 was detected at concentrations of 0.15 and 0.20 pCi/l in two of four samples. Alpha-emitting radionuclides in the ground water originated from the dissolution of U-rich granitic rocks in the Sierra Nevada by CO2, oxygenated water. Dissolution of primary minerals, mainly titanite (sphene) in the granitic rocks, releases U to the water. Dissolved U is probably removed from the water by adsorption on Fe- and Mn-oxide coatings on fracture surfaces and fine-grained sediment, by adsorption on organic matter, and by coprecipitation with Fe and Mn oxides. These coated sediments are transported throughout the basin by fluvial processes. Thus, U is transported as dissolved and adsorbed species. A rise in the water table in the Carson Desert because of irrigation has resulted in the oxidation of U-rich organic matter and dissolution of U-bearing coatings on sediments, producing unusually high U concentration in the ground water. Alpha activity in the ground water is almost entirely from the decay of U dissolved in the water. Beta activity in ground water samples is primarily from the decay of 40K dissolved in the water and ingrowth of 238U progeny in the sample before analysis. Approximately one-half of the measured beta activity may not be present in ground water in the aquifer, but instead is produced in the sample after collection and before analysis. Potassium-40 is primarily from the dissolution of K-containing minerals, probably K-feldspar and biotite. Radon-222 is primarily from the decay of 226Ra in the aquifer materials. Radium in the ground water is thought to be mainly from alpha recoil associated with the decay of Th in the aquifer material. Some Ra may be from dissolution (or desorption) or Ra-rich coatings on sediments. ?? 1993.

Temporal Variability of Microplastic Concentrations in Freshwater Streams

NASA Astrophysics Data System (ADS)

Watkins, L.; Walter, M. T.

2016-12-01

Plastic pollution, specifically the size fraction less than 5mm known as microplastics, is an emerging contaminant in waterways worldwide. The ability of microplastics to adsorb and transport contaminants and microbes, as well as be ingested by organisms, makes them a concern in both freshwater and marine ecosystems. Recent efforts to determine the extent of microplastic pollution are increasingly focused on freshwater systems, but most studies have reported concentrations at a single time-point; few have begun to uncover how plastic concentrations in riverine systems may change through time. We hypothesize the time of day and season of sampling influences the concentrations of microplastics in water samples and more specifically, that daytime stormflow samples contain the highest microplastic concentrations due to maximized runoff and wastewater discharge. In order to test this hypothesis, we sampled in two similar streams in Ithaca, New York using a 333µm mesh net deployed within the thalweg. Repeat samples were collected to identify diurnal patterns as well as monthly variation. Samples were processed in the laboratory following the NOAA wet peroxide oxidation protocol. This work improves our ability to interpret existing single-time-point survey results by providing information on how microplastic concentrations change over time and whether concentrations in existing stream studies are likely representative of their location. Additionally, these results will inform future studies by providing insight into representative sample timing and capturing temporal trends for the purposes of modeling and of developing regulations for microplastic pollution.

Surveillance of Strontium-90 in Foods after the Fukushima Daiichi Nuclear Power Plant Accident.

PubMed

Nabeshi, Hiromi; Tsutsumi, Tomoaki; Uekusa, Yoshinori; Hachisuka, Akiko; Matsuda, Rieko; Teshima, Reiko

2015-01-01

As a result of the Fukushima Daiichi nuclear power plant (NPP) accident, various radionuclides were released into the environment. In this study, we surveyed strontium-90 ((90)Sr) concentrations in several foodstuffs. Strontium-90 is thought to be the third most important residual radionuclide in food collected after the Fukushima Daiichi, NPP accident after following cesium-137 ((137)Cs) and cesium-134 ((134)Cs). Results of (90)Sr analyses indicated that (90)Sr was detect in 25 of the 40 radioactive cesium (r-Cs) positive samples collected in areas around the Fukushima Daiichi NPP, ranging in distance from 50 to 250 km. R-Cs positive samples were defined as containing both (134)Cs and (137)Cs which are considered to be indicators of the after-effects of the Fukushima Daiichi NPP accident. We also detected (90)Sr in 8 of 13 r-Cs negative samples, in which (134)Cs was not detected. Strontium-90 concentrations in the r-Cs positive samples did not significantly exceed the (90)Sr concentrations in r-Cs negative samples or the (90)Sr concentration ranges in comparable food groups found in previous surveys before the Fukushima Daiichi NPP accident. Thus, (90)Sr concentrations in r-Cs positive samples were indistinguishable from the background (90)Sr concentrations arising from global fallout prior to the Fukushima accident, suggesting that no marked increase of (90)Sr concentrations has occurred in r-Cs positive samples as a result of the Fukushima Daiichi NPP accident.

A new method for calculation of the chlorine demand of natural and treated waters.

PubMed

Warton, Ben; Heitz, Anna; Joll, Cynthia; Kagi, Robert

2006-08-01

Conventional methods of calculating chlorine demand are dose dependent, making intercomparison of samples difficult, especially in cases where the samples contain substantially different concentrations of dissolved organic carbon (DOC), or other chlorine-consuming species. Using the method presented here, the values obtained for chlorine demand are normalised, allowing valid comparison of chlorine demand between samples, independent of the chlorine dose. Since the method is not dose dependent, samples with substantially differing water quality characteristics can be reliably compared. In our method, we dosed separate aliquots of a water sample with different chlorine concentrations, and periodically measured the residual chlorine concentrations in these subsamples. The chlorine decay data obtained in this way were then fitted to first-order exponential decay functions, corresponding to short-term demand (0-4h) and long-term demand (4-168 h). From the derived decay functions, the residual concentrations at a given time within the experimental time window were calculated and plotted against the corresponding initial chlorine concentrations, giving a linear relationship. From this linear function, it was then possible to determine the residual chlorine concentration for any initial concentration (i.e. dose). Thus, using this method, the initial chlorine dose required to give any residual chlorine concentration can be calculated for any time within the experimental time window, from a single set of experimental data.

Lanthanide, yttrium, and zirconium anomalies in the Fire Clay coal bed, Eastern Kentucky

USGS Publications Warehouse

Hower, J.C.; Ruppert, L.F.; Eble, C.F.

1999-01-01

The Fire Clay coal bed in the Central Appalachian basin region contains a laterally-persistent tonstein that is found in the coal throughout most of its areal extent. The tonstein contains an array of minerals, including sanidine, ??-quartz, anatase and euhedral zircon, thhat constitutes strong evidence for a volcanic origin of the parting. For this study, five samples of the tonstein and four sets of coal samples underlying the tonstein were collected from five sites in eastern Kentucky. Inductively coupled plasma-mass spectroscopy (ICP-MS) analysis of the tonstein and underlying coal collected from four sites in eastern Kentucky show that although Zr concentrations are high in the tonstein (570-1820 ppm on a coal-ash basis (cab)), they are highest in the coal directly underlying the tonstein (2870-4540 ppm (cab)). A similar enrichment pattern is observed in the concentration of Y plus the sum of the rare earth elements (Y + ??REE): total Y + ??REE concentrations in the five tonstein samples range from 511 to 565 ppm (cab). However, Y + ??REE contents are highest in the coals directly underlying the tonsteins: values range from 1965 to 4198 ppm (cab). Scanning electron microscopy of samples from coal which directly underlies two of the tonstein samples show that REE-rich phosphate, tentatively identified as monazite, commonly infills cracks in clays and cells in clarain and vitrain. Zircon is rare and commonly subhedral. On the basis of coal chemistry and grain morphology, we suggest that volcanic components in the tonstein were leached by ground water. The leachate, rich in Y and REE precipitated as authigenic mineral phases in the underlying coal.The Fire Clay coal bed in the Central Appalachian basin region contains a laterally-persistent tonstein that is found in the coal throughout most of its areal extent. The tonstein contains an array of minerals, including sanidine, ??-quartz, anatase and euhedral zircon, that constitutes strong evidence for a volcanic origin of the parting. For this study, five samples of the tonstein and four sets of coal samples underlying the tonstein were collected from five sites in eastern Kentucky. Inductively coupled plasma-mass spectroscopy (ICP-MS) analysis of the tonstein and underlying coal collected from four sites in eastern Kentucky show that although Zr concentrations are high in the tonstein (570-1820 ppm on a coal-ash basis (cab)), they are highest in the coal directly underlying the tonstein (2870-4540 ppm (cab)). A similar enrichment pattern is observed in the concentration of Y plus the sum of the rare earth elements (Y+???REE): total Y+???REE concentrations in the five tonstein samples range from 511 to 565 ppm (cab). However, Y+???REE contents are highest in the coals directly underlying the tonsteins: values range from 1965 to 4198 ppm (cab). Scanning electron microscopy of samples from coal which directly underlies two of the tonstein samples show that REE-rich phosphate, tentatively identified as monazite, commonly infills cracks in clays and cells in clarain and vitrain. Zircon is rare and commonly subhedral. On the basis of coal chemistry and grain morphology, we suggest that volcanic components in the tonstein were leached by ground water. The leachate, rich in Y and REE precipitated as authigenic mineral phases in the underlying coal.

Development of a 100 nmol mol(-1) propane-in-air SRM for automobile-exhaust testing for new low-emission requirements.

PubMed

Rhoderick, George C

2007-04-01

New US federal low-level automobile emission requirements, for example zero-level-emission vehicle (ZLEV), for hydrocarbons and other species, have resulted in the need by manufacturers for new certified reference materials. The new emission requirement for hydrocarbons requires the use, by automobile manufacturing testing facilities, of a 100 nmol mol(-1) propane in air gas standard. Emission-measurement instruments are required, by federal law, to be calibrated with National Institute of Standards and Technology (NIST) traceable reference materials. Because a NIST standard reference material (SRM) containing 100 nmol mol(-1) propane was not available, the US Environmental Protection Agency (EPA) and the Automobile Industry/Government Emissions Research Consortium (AIGER) requested that NIST develop such an SRM. A cylinder lot of 30 gas mixtures containing 100 nmol mol(-1) propane in air was prepared in 6-L aluminium gas cylinders by a specialty gas company and delivered to the Gas Metrology Group at NIST. Another mixture, contained in a 30-L aluminium cylinder and included in the lot, was used as a lot standard (LS). Using gas chromatography with flame-ionization detection all 30 samples were compared to the LS to obtain the average of six peak-area ratios to the LS for each sample with standard deviations of <0.31%. The average sample-to-LS ratio determinations resulted in a range of 0.9828 to 0.9888, a spread of 0.0060, which corresponds to a relative standard deviation of 0.15% of the average for all 30 samples. NIST developed its first set of five propane in air primary gravimetric standards covering a concentration range 91 to 103 nmol mol(-1) with relative uncertainties of 0.15%. This new suite of propane gravimetric standards was used to analyze and assign a concentration value to the SRM LS. On the basis of these data each SRM sample was individually certified, furnishing the desired relative expanded uncertainty of +/-0.5%. Because automobile companies use total hydrocarbons to make their measurements, it was also vital to assign a methane concentration to the SRM samples. Some of the SRM samples were analyzed and found to contain 1.2 nmol mol(-1) methane. Twenty-five of the samples were certified and released as SRM 2765.

Chemotactic selection of pollutant degrading soil bacteria

DOEpatents

Hazen, Terry C.

1994-01-01

A method for identifying soil microbial strains which may be bacterial degraders of pollutants comprising the steps of placing a concentration of a pollutant in a substantially closed container, placing the container in a sample of soil for a period of time ranging from one minute to several hours, retrieving the container, collecting the contents of the container, and microscopically determining the identity of the bacteria present. Different concentrations of the pollutant can be used to determine which bacteria respond to each concentration. The method can be used for characterizing a polluted site or for looking for naturally occurring biological degraders of the pollutant. Then bacteria identified as degraders of the pollutant and as chemotactically attracted to the pollutant are used to inoculate contaminated soil. To enhance the effect of the bacteria on the pollutant, nutrients are cyclicly provided to the bacteria then withheld to alternately build up the size of the bacterial colony or community and then allow it to degrade the pollutant.

Integrated microfluidic systems for sample preparation and detection of respiratory pathogen Bordetella pertussis.

PubMed

de la Rosa, Carlos; Prakash, Ranjit; Tilley, Peter A; Fox, Julie D; Kaler, Karan V i S

2007-01-01

An integrated microfluidic system for combined manipulation, pre-concentration, and lysis of samples containing Bordetella pertussis by dielectrophoresis and electroporation has been developed and implemented. The microfluidic device was able to pre-concentrate the amount of B. pertussis cells present in 200 microl of a B. pertussis suspension stock into a 20 microl volume. The device exhibited optimal sample pre-concentration of 6.7x at a stock value of 10(3) cfu/ml and at a flow rate of 250 microl/h. Electro-disruption experiments showed that on-chip-based electroporation is an effective solution for lysis of B. pertussis cells that is easily integrated with dielectrophoresis assisted pre-concentration procedures. Pulsed voltage applied, number of pulses, and presence of potassium chloride in a B. pertussis suspension showed a reduction in B. pertussis cell viability by electroporation; and transmission electron microscopy confirmed B. pertussis cell disruption by electroporation. Genetic amplification and detection of the pre-concentrated sample employing an integrated chip-based system demonstrated a complete chip approach for pathogen detection.

Stability of ramipril in water, apple juice, and applesauce.

PubMed

Allen, L V; Stiles, M L; Prince, S J; McLaury, H J; Sylvestri, M F

1995-11-01

The stability of ramipril in water, in apple juice, and in applesauce was studied. The contents of a single capsule each of ramipril 1.25, 2.5, and 5 mg were mixed in glass beakers with 120 mL of deionized and filtered water, apple juice, or applesauce. Each mixture was apportioned into 10 120-mL amber polyethylene terephthalate (PET) containers. Five of the containers in each set were stored at 23 degrees C, and samples were taken at 0, 1, 2, 6, 12, and 24 hours. The other five containers were stored at 3 degrees C, and samples were taken at 4, 8, 12, 24, and 48 hours. The samples were analyzed for ramipril concentration by stability-indicating high-performance liquid chromatography (HPLC). The quantity of drug remaining in the PET container after "administration" was determined by mixing the contents of single 5-mg ramipril capsules with 60 mL of apple juice, pouring the mixture into a waste receptacle, rinsing the PET container three separate times with 10 mL of water, and analyzing the pooled fluid from these rinses for ramipril concentration by HPLC. Under no condition did the percentage of ramipril remaining drop below 90%. No peaks for degradation products appeared in the chromatograms. The mean +/- S.D. quantity of ramipril remaining in the PET containers after draining was 0.3 +/- 0.3% for the apple juice. Ramipril from 1.25-, 2.5-, and 5-mg capsules mixed in water, in apple juice, and in applesauce was stable for 24 hours at 23 degrees C and for 48 hours at 3 degrees C.

Effect of carrageenan addition on the rennet-induced gelation of skim milk.

PubMed

Wang, Fang; Zhang, Wei; Ren, Fazheng

2016-09-01

Carrageenan (CG) (κ-CG, ι-CG and λ-CG) was added to skim milk and the rennet-induced aggregation was studied. Caseinomacropeptide (CMP) release, diffusing wave spectroscopy (DWS) and rheology were used to follow the structural dynamics of casein micelles during gelation. The influence of carrageenan on the nature of protein interactions in the gels was investigated using a combination of ultracentrifugation and specific dissociating agents. For the recombined samples containing κ-CG and low concentrations of ι-CG and λ-CG, the CMP release was slowed down; however, the development of DWS and rheological parameters was similar to that of the control sample, and the increase in the incorporation of proteins through calcium bridges and hydrophobic interactions may be the most likely contributors. For the recombined samples containing high concentrations of ι-CG and λ-CG, other factors may impede the gel formation process. High concentrations of ι-CG and λ-CG strongly interfered with the rennet-induced aggregation, interrupted the interaction of caseins and therefore may contribute to good quality of low-fat cheese. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Aluminium (Al) speciation in serum and urine after subcutaneous venom immunotherapy with Al as adjuvant.

PubMed

Michalke, Bernhard; Kramer, Matthias F; Brehler, Randolf

2018-02-21

Aluminium is associated with disorders and is the commonly used vaccine adjuvant. Understanding the mechanisms of how Al is transported, metabolized or of its toxicity depends on the knowledge of Al-interactions with bioligands, i.e. Al-species. Al-speciation in serum is difficult because of low concentration and the risk of exogenous Al contamination. Furthermore, Al-measurements may be hampered according to various interferences. This study aims for developing quality controlled protocols for reliable Al- and Al-species determination and for investigating probable differences in Al (-speciation) after Al-containing subcutaneous immunotherapy (SIT). Sample donors were recruited either for the control group ("class-0", they never had been treated with SIT containing an Al-depot extract) or for the SIT-group ("class-1", they previously had been treated with SIT for insect venom allergy with an Al-depot extract). Blood was drawn for medical reasons and serum prepared. Additionally, some sample donors collected 24-h-urine. They had been informed (and they consented) about the scientific use of their samples. The study was approved by the ethic committee of the "Medical Association Westphalia-Lippe" and of the University of Münster, evaluating the study positively (No. 2013-667-f-S). We applied quality controlled sample preparation and interference-free Al detection by ICP sectorfield-mass spectrometry. Al-species were analysed using size-exclusion-chromatography-ICP-qMS. Al-concentrations or speciation in urine samples showed no differences between class-0 and class-1. Al-citrate was the main uric Al-species. In serum elevated Al-concentrations were found for both classes, with class-1 samples being significantly higher than class-0 (p = 0.041), but class-0 samples being approximately 10-fold too high compared to reference values from non-exposed persons. We identified gel-monovettes as contamination source. In contamination-free samples from HNO 3 -prewashed gel-free monovettes (n = 27) there was no difference in the serum Al concentration between the two patient groups (p = 0.669) INTERPRETATION: Thorough cleaning of sample preparation ware and use of gel-free monovettes is decisive for an accurate Al analysis in serum. Without these steps, wrong analysis and wrong conclusions are likely. We conclude that gel-monovettes are unsuitable for blood sampling with subsequent Al-analysis. Whether Al in serum is elevated after SIT treatment containing an Al-depot extract, or not, remains inconclusive as the non-contaminated sample size was small. Copyright © 2018 Elsevier GmbH. All rights reserved.

Photoreflectance measurements of unintentional impurity concentrations in undoped GaAs

NASA Astrophysics Data System (ADS)

Sydor, Michael; Angelo, James; Mitchel, William; Haas, T. W.; Yen, Ming-Yuan

1989-07-01

Modulated photoreflectance is used to measure the unintentional impurity concentrations in undoped epitaxial GaAs. A photoreflectance signal above the band gap spreads with the unintentional impurity concentrations and shows well-defined Franz-Keldysh peaks whose separation provide a good measure of the current carrier concentrations. In samples less than 3-micron thick, a photoreflectance signal at the band edge contains a substrate-epilayer interface effect which precludes the analysis of the data by using the customary third derivative functional fits for low electric fields.

Mg-containing hydroxyapatite coatings on Ti-6Al-4V alloy for dental materials

NASA Astrophysics Data System (ADS)

Yu, Ji-Min; Choe, Han-Cheol

2018-02-01

In this study, Mg-containing hydroxyapatite coatings on Ti-6A1-4 V alloy for dental materials were researched using various experimental instruments. Plasma electrolytic oxidation (PEO) was performed in electrolytes containing Mg (symbols of specimens: CaP, 5M%, 10M%, and 20M%) at 280 V for 3 min. The electrolyte used for PEO was produced by mixing Ca(CH3COO)2·H2O, C3H7NaCaO6P, and MgCl2·6H2O. The phases and composition of the oxide films were evaluated by X-ray diffraction and field-emission scanning electron microscopy with energy dispersive X-ray spectrometry. The irregularity of the surface, pore size, and number of pores decreased as the Mg concentration increased. The ratio of the areas occupied and not occupied by pores decreased as the Mg concentration increased, with the numbers of both large and small pores decreasing with increasing Mg concentration. The number of particles on the internal surfaces of pores was increased as the Mg content increased. Mg content of all samples containing Mg ions showed higher in the pore outside than that of pore inside, whereas the Ca content was higher inside the pores. The P content of samples with the addition of Mg ions showed higher values inside the pores than outside. The Ca/P and [Mg + Ca]/P molar ratios in the PEO films decreased with Mg content. The crystallite size of anatase was increased with increasing Mg concentration in the solution.

Reconnaissance geochemical survey of the At Taif-Al Bahah region, southern Hijaz, Kingdom of Saudi Arabia

USGS Publications Warehouse

Du Bray, E.A.; Doebrich, J.L.

1982-01-01

An area south of At Taif containing significant tungsten was confirmed and found to be larger than initially determined. A possible porphyry copper pluton was discovered 50 km south-southeast of At Taif. Thirty kilometers south of At Taif, a low-grade tin anomaly associated with an S-type granite was identified. In addition, the sampling identified seven anomalous areas attributable to rock geochemically atypical of the study region. Finally, although samples from the A1 Lith-Hajrah area collected for an earlier study were found to contain anomalous concentrations of tungsten, samples collected there during this study do not support those findings.

Reconnaissance of volatile organic compounds in the subsurface at Rutgers University, Busch Campus, Piscataway Township, New Jersey

USGS Publications Warehouse

dePaul, V.T.

1996-01-01

During 1991-92, the U.S. Geological Survey conducted a hydrogeologic reconnaissance at a site near the Rutgers University, Busch Campus, Chemical Engineering building, C-Wing. Results of analyses of the soil-gas samples, which were collected at 43 locations, indicated the presence of volatile organic compounds, primarily carbon tetrachloride, near the C-Wing building and about 550 feet downgradient from and southwest of the C-Wing building. Concentrations of the compound in soil-gas samples were highest (2.1 ug/L (micrograms per liter)) along the southwestern wall of the C-Wing building. Ground-water samples were collected at depths as great as 55 feet from five wells and piezometers near the C-Wing building. Samples collected along the southwestern wall of the building also contained the highest concentrations of volatile organic compounds. Concentrations of carbon tetrachloride in the ground-water samples ranged from < 0.35 ug/L to 3,400 ug/L, and concentrations of tetrachloro- ethylene ranged from < 0.28 ug/L to 85 ug/L. Ground-water samples collected at depths of 55 feet or more from two wells located on the Rutgers University Golf Course about 2,400 feet down- gradient from the C-Wing building contained concentrations of tetrachloroethylene as great as 17.7 ug/L. Water levels measured in six wells and six piezometers indicated that the general flow direction in the shallow part of the aquifer is to the southwest of the C-Wing building. An electrical-resistivity survey was conducted by azimuthal resistivity techniques. The results of the survey were consistent with field measurements, and the dominant vertical fractures near the Busch Campus trend northeast. An electromagnetic survey was ineffective as a result of cultural interferences and could not be used to determine the hydrogeologic characteristics of the site.

Occurrence of Fumigants and Hazardous Off-gassing Chemicals in Shipping Containers Arriving in Sweden

PubMed Central

Johanson, Gunnar

2017-01-01

Abstract Containerized cargo shipment makes up the backbone of international trade. The principal aim of this cross-sectional study was to establish a qualitative and quantitative description of gaseous fumigants and volatile off-gassing substances facing workers tasked with entering shipping containers. A total of 372 packed and 119 empty shipping containers were sampled in six ports and two distribution centers in Sweden. Fourier-transform infrared spectrometry (FTIR) and photoionization detection (PID) were the analytical methods applied to the bulk of samples. A small number of adsorbent samples were analyzed using gas chromatography–mass spectrometry (GC–MS). The results were compared to Swedish occupational exposure limits (OELs), the closest parallel to relevant work situations. Based on the FTIR analyses, 30 of 249 (12%) containers arrived with concentrations of fumigants and off-gassing substances above the 8-h OELs and close to 7% were above the short-term exposure limits. Eight detected chemicals were classified as carcinogens and 4% of the containers arrived with levels of carcinogens above the OELs, at a maximum 30 times the 8-h OEL. Considerable differences were observed between ports, ranging from 0 to 33% of containers arriving with concentrations above the OELs. It is believed that all observation results, apart from a single instance of a confirmed fumigant, phosphine, at 3 p.p.m., and possibly three instances of carbon dioxide, can be attributed to off-gassing substances. The FTIR methodology proved useful for quick preliminary checks and in-depth screening and identification. The PID method produced both false-negative and false-positive results where only 48% matched the FTIR observations. Adsorbent sampling with GC–MS analysis was useful for confirming volatile organic compounds but was deemed too slow for day-to-day screening. The high frequency of contaminated containers, the detection of several carcinogens, and the sporadic occurrences of high levels of fumigants are serious concerns that need to be properly recognized in order to protect the workers at risk. PMID:28395344

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

Andrews, V.E.

Naturally occurring radioactivity was measured in the atmospheric emissions and process materials of a thermal phosphate (elemental phosphorus) plant. Representative exhaust stack samples were collected from each process in the plant. The phosphate ore contained 12 to 20 parts per million uranium. Processes, emission points, and emission controls are described. Radioactivity concentrations and emission rates from the sources sampled are given.

40 CFR 98.154 - Monitoring and QA/QC requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... the concentrations of the process samples. (b) The mass flow of the product stream containing the HFC... concentration and volumetric flow rate determined by measurement of volumetric flow rate using EPA Method 2, 2A... volumetric flow rate at the inlet or by a metering device for HFC-23 sent to the device. Determine a new...

Major and trace elements in organically or conventionally produced milk.

PubMed

Hermansen, John E; Badsberg, Jens H; Kristensen, Troels; Gundersen, Vagn

2005-08-01

A total of 480 samples of milk from 10 organically and 10 conventionally producing dairy farms in Denmark and covering 8 sampling periods over 1 year (triplicate samplings) were analysed for 45 trace elements and 6 major elements by high-resolution inductively coupled plasma mass spectrometry and inductively coupled plasma atomic emission spectrometry. Sampling, sample preparation, and analysis of the samples were performed under carefully controlled contamination-free conditions. The dairy cattle breeds were Danish-Holstein or Jersey. Sources of variance were quantified, and differences between production systems and breeds were tested. The major source of variation for most elements was week of sampling. Concentrations of Al, Cu, Fe, Mo, Rb, Se, and Zn were within published ranges. Concentrations of As, Cd, Cr, Mn and Pb were lower, and concentrations of Co and Sr were higher than published ranges. Compared with Holsteins, Jerseys produced milk with higher concentrations of Ba, Ca, Cu, Fe, Mg, Mn, Mo, P, Rh, and Zn and with a lower concentration of Bi. The organically produced milk, compared with conventionally produced milk, contained a significantly higher concentration of Mo (48 v. 37 ng/g) and a lower concentration of Ba (43 v. 62 ng/g), Eu (4 v. 7 ng/g), Mn (16 v. 20 ng/g) and Zn (4400 v. 5150 ng/g respectively). The investigation yielded typical concentrations for the following trace elements in milk, for which no or very few data are available: Ba, Bi, Ce, Cs, Eu, Ga, Gd, In, La, Nb, Nd, Pd, Pr, Rh, Sb, Sm, Tb, Te, Th, Ti, Tl, U, V, Y, and Zr.

Stability of encapsulated beef-like flavourings prepared from enzymatically hydrolysed mushroom proteins with other precursors under conventional and microwave heating.

PubMed

Lotfy, Shereen N; Fadel, Hoda H M; El-Ghorab, Ahmed H; Shaheen, Mohamed S

2015-11-15

A comparative study was carried out between two beef-like flavourings prepared by conventional and microwave heating (CBF and MBF) of enzymatic hydrolysate of mushroom protein with other flavour precursors. GC-MS analysis of the isolated volatiles revealed that the thiol containing compounds were the predominate in both samples. However, MBF comprised higher concentration of these compounds (13.84 ± 0.06%) than CBF (10.74 ± 0.06%). The effect of microencapsulation with gum Arabic by using spray drying on the odour profile and volatile compounds of the two encapsulated samples (E-CBF and E-MBF) was investigated. The results revealed significant qualitative and quantitative variations in the volatiles of both samples. The highly volatile compounds decreased remarkably in concentration with encapsulation, while the pyrazines, thiazoles and disulphides showed opposite trend. The significant decrease in the thiol containing compounds in E-CBF and E-MBF were attributed to their oxidation to other compounds such as disulphide compounds which showed significant increase in the encapsulated samples. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect of salt concentrations and drying methods on the quality and formation of histamine in dried milkfish (Chanos chanos).

PubMed

Hwang, Chiu-Chu; Lin, Chia-Min; Kung, Hsien-Feng; Huang, Ya-Ling; Hwang, Deng-Fwu; Su, Yi-Cheng; Tsai, Yung-Hsiang

2012-11-15

The effects of salt concentrations (0-15.0%) and drying methods on the quality of dried milkfish were studied. The results showed that the levels of aerobic plate counts, total coliform, water activity, moisture contents, total volatile basic nitrogen (TVBN) and thiobarbituric acid (TBA) of the dried milkfish samples prepared with the same drying method decreased with increased salt concentrations. The samples prepared with the cold-air drying method had better quality in term of lower TVBN and TBA values than those of samples prepared with other drying methods. The histamine contents in all samples, except two, prepared with various salt concentrations by different drying methods were less than 1.9 mg/100 g. Two unsalted samples prepared with hot-air drying at 35 °C and sun drying methods were found to contain histamine at levels of 249.7 and 67.4 mg/100 g, respectively, which were higher than the potential hazard level of 50 mg/100 g. Copyright © 2012 Elsevier Ltd. All rights reserved.

STATISTICAL ANALYSIS OF TANK 5 FLOOR SAMPLE RESULTS

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

Shine, E.

2012-03-14

Sampling has been completed for the characterization of the residual material on the floor of Tank 5 in the F-Area Tank Farm at the Savannah River Site (SRS), near Aiken, SC. The sampling was performed by Savannah River Remediation (SRR) LLC using a stratified random sampling plan with volume-proportional compositing. The plan consisted of partitioning the residual material on the floor of Tank 5 into three non-overlapping strata: two strata enclosed accumulations, and a third stratum consisted of a thin layer of material outside the regions of the two accumulations. Each of three composite samples was constructed from five primarymore » sample locations of residual material on the floor of Tank 5. Three of the primary samples were obtained from the stratum containing the thin layer of material, and one primary sample was obtained from each of the two strata containing an accumulation. This report documents the statistical analyses of the analytical results for the composite samples. The objective of the analysis is to determine the mean concentrations and upper 95% confidence (UCL95) bounds for the mean concentrations for a set of analytes in the tank residuals. The statistical procedures employed in the analyses were consistent with the Environmental Protection Agency (EPA) technical guidance by Singh and others [2010]. Savannah River National Laboratory (SRNL) measured the sample bulk density, nonvolatile beta, gross alpha, radionuclide, inorganic, and anion concentrations three times for each of the composite samples. The analyte concentration data were partitioned into three separate groups for further analysis: analytes with every measurement above their minimum detectable concentrations (MDCs), analytes with no measurements above their MDCs, and analytes with a mixture of some measurement results above and below their MDCs. The means, standard deviations, and UCL95s were computed for the analytes in the two groups that had at least some measurements above their MDCs. The identification of distributions and the selection of UCL95 procedures generally followed the protocol in Singh, Armbya, and Singh [2010]. When all of an analyte's measurements lie below their MDCs, only a summary of the MDCs can be provided. The measurement results reported by SRNL are listed in Appendix A, and the results of this analysis are reported in Appendix B. The data were generally found to follow a normal distribution, and to be homogeneous across composite samples.« less

Statistical Analysis of Tank 5 Floor Sample Results

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

Shine, E. P.

2013-01-31

Sampling has been completed for the characterization of the residual material on the floor of Tank 5 in the F-Area Tank Farm at the Savannah River Site (SRS), near Aiken, SC. The sampling was performed by Savannah River Remediation (SRR) LLC using a stratified random sampling plan with volume-proportional compositing. The plan consisted of partitioning the residual material on the floor of Tank 5 into three non-overlapping strata: two strata enclosed accumulations, and a third stratum consisted of a thin layer of material outside the regions of the two accumulations. Each of three composite samples was constructed from five primarymore » sample locations of residual material on the floor of Tank 5. Three of the primary samples were obtained from the stratum containing the thin layer of material, and one primary sample was obtained from each of the two strata containing an accumulation. This report documents the statistical analyses of the analytical results for the composite samples. The objective of the analysis is to determine the mean concentrations and upper 95% confidence (UCL95) bounds for the mean concentrations for a set of analytes in the tank residuals. The statistical procedures employed in the analyses were consistent with the Environmental Protection Agency (EPA) technical guidance by Singh and others [2010]. Savannah River National Laboratory (SRNL) measured the sample bulk density, nonvolatile beta, gross alpha, and the radionuclide1, elemental, and chemical concentrations three times for each of the composite samples. The analyte concentration data were partitioned into three separate groups for further analysis: analytes with every measurement above their minimum detectable concentrations (MDCs), analytes with no measurements above their MDCs, and analytes with a mixture of some measurement results above and below their MDCs. The means, standard deviations, and UCL95s were computed for the analytes in the two groups that had at least some measurements above their MDCs. The identification of distributions and the selection of UCL95 procedures generally followed the protocol in Singh, Armbya, and Singh [2010]. When all of an analyte's measurements lie below their MDCs, only a summary of the MDCs can be provided. The measurement results reported by SRNL are listed, and the results of this analysis are reported. The data were generally found to follow a normal distribution, and to be homogenous across composite samples.« less

Statistical Analysis Of Tank 5 Floor Sample Results

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

Shine, E. P.

2012-08-01

Sampling has been completed for the characterization of the residual material on the floor of Tank 5 in the F-Area Tank Farm at the Savannah River Site (SRS), near Aiken, SC. The sampling was performed by Savannah River Remediation (SRR) LLC using a stratified random sampling plan with volume-proportional compositing. The plan consisted of partitioning the residual material on the floor of Tank 5 into three non-overlapping strata: two strata enclosed accumulations, and a third stratum consisted of a thin layer of material outside the regions of the two accumulations. Each of three composite samples was constructed from five primarymore » sample locations of residual material on the floor of Tank 5. Three of the primary samples were obtained from the stratum containing the thin layer of material, and one primary sample was obtained from each of the two strata containing an accumulation. This report documents the statistical analyses of the analytical results for the composite samples. The objective of the analysis is to determine the mean concentrations and upper 95% confidence (UCL95) bounds for the mean concentrations for a set of analytes in the tank residuals. The statistical procedures employed in the analyses were consistent with the Environmental Protection Agency (EPA) technical guidance by Singh and others [2010]. Savannah River National Laboratory (SRNL) measured the sample bulk density, nonvolatile beta, gross alpha, and the radionuclide, elemental, and chemical concentrations three times for each of the composite samples. The analyte concentration data were partitioned into three separate groups for further analysis: analytes with every measurement above their minimum detectable concentrations (MDCs), analytes with no measurements above their MDCs, and analytes with a mixture of some measurement results above and below their MDCs. The means, standard deviations, and UCL95s were computed for the analytes in the two groups that had at least some measurements above their MDCs. The identification of distributions and the selection of UCL95 procedures generally followed the protocol in Singh, Armbya, and Singh [2010]. When all of an analyte's measurements lie below their MDCs, only a summary of the MDCs can be provided. The measurement results reported by SRNL are listed in Appendix A, and the results of this analysis are reported in Appendix B. The data were generally found to follow a normal distribution, and to be homogenous across composite samples.« less

Variables controlling the recovery of ignitable liquid residues from simulated fire debris samples using solid-phase microextraction/gas chromatography

NASA Astrophysics Data System (ADS)

Furton, Kenneth G.; Almirall, Jose R.; Wang, Jing

1999-02-01

In this paper, we present data comparing a variety of different conditions for extracting ignitable liquid residues from simulated fire debris samples in order to optimize the conditions for using Solid Phase Microextraction. A simulated accelerant mixture containing 30 components, including those from light petroleum distillates, medium petroleum distillates and heavy petroleum distillates were used to study the important variables controlling Solid Phase Microextraction (SPME) recoveries. SPME is an inexpensive, rapid and sensitive method for the analysis of volatile residues from the headspace over solid debris samples in a container or directly from aqueous samples followed by GC. The relative effects of controllable variables, including fiber chemistry, adsorption and desorption temperature, extraction time, and desorption time, have been optimized. The addition of water and ethanol to simulated debris samples in a can was shown to increase the sensitivity when using headspace SPME extraction. The relative enhancement of sensitivity has been compared as a function of the hydrocarbon chain length, sample temperature, time, and added ethanol concentrations. The technique has also been optimized to the extraction of accelerants directly from water added to the fire debris samples. The optimum adsorption time for the low molecular weight components was found to be approximately 25 minutes. The high molecular weight components were found at a higher concentration the longer the fiber was exposed to the headspace (up to 1 hr). The higher molecular weight components were also found in higher concentrations in the headspace when water and/or ethanol was added to the debris.

Insights into controls on hexavalent chromium in groundwater provided by environmental tracers, Sacramento Valley, California, USA

USGS Publications Warehouse

Manning, Andrew H.; Mills, Christopher T.; Morrison, Jean M.; Ball, Lyndsay B.

2015-01-01

Environmental tracers are useful for determining groundwater age and recharge source, yet their application in studies of geogenic Cr(VI) in groundwater has been limited. Environmental tracer data from 166 wells located in the Sacramento Valley, northern California, were interpreted and compared to Cr concentrations to determine the origin and age of groundwater with elevated Cr(VI), and better understand where Cr(VI) becomes mobilized and how it evolves along flowpaths. In addition to major ion and trace element concentrations, the dataset includes δ18O, δ2H, 3H concentration, 14C activity (of dissolved inorganic C), δ13C, 3He/4He ratio, and noble gas concentrations (He, Ne, Ar, Kr, Xe). Noble gas recharge temperatures (NGTs) were computed, and age-related tracers were interpreted in combination to constrain the age distribution in samples and sort them into six different age categories spanning from <60 yr old to >10,000 yr old. Nearly all measured Cr is in the form of Cr(IV). Concentrations range from <1 to 46 μg L−1, with 10% exceeding the state of California’s Cr(VI) maximum contaminant level of 10 μg L−1. Two groups with elevated Cr(VI) (⩾5 μg L−1) were identified. Group 1 samples are from the southern part of the valley and contain modern (<60 yr old) water, have elevated NO3− concentrations (>3 mg L−1), and commonly have δ18O values enriched relative to local precipitation. These samples likely contain irrigation water and are elevated due to accelerated mobilization of Cr(VI) in the unsaturated zone (UZ) in irrigated areas. Group 2 samples are from throughout the valley and typically contain water 1000–10,000 yr old, have δ18O values consistent with local precipitation, and have unexpectedly warm NGTs. Chromium(VI) concentrations in Group 2 samples may be elevated for multiple reasons, but the hypothesis most consistent with all available data (notably, the warm NGTs) is a relatively long UZ residence time due to recharge through a deep UZ near the margin of the basin. A possible explanation for why Cr(VI) may be primarily mobilized in the UZ rather than farther along flowpaths in the oxic portion of the saturated zone is more dynamic cycling of Mn in the UZ due to transient moisture and redox conditions.

Water-Quality Conditions of Chester Creek, Anchorage, Alaska, 1998-2001

USGS Publications Warehouse

Glass, Roy L.; Ourso, Robert T.

2006-01-01

Between October 1998 and September 2001, the U.S. Geological Survey's National Water-Quality Assessment Program evaluated the water-quality conditions of Chester Creek, a stream draining forest and urban settings in Anchorage, Alaska. Data collection included water, streambed sediments, lakebed sediments, and aquatic organisms samples from urban sites along the stream. Urban land use ranged from less than 1 percent of the basin above the furthest upstream site to 46 percent above the most downstream site. Findings suggest that water quality of Chester Creek declines in the downstream direction and as urbanization in the watershed increases. Water samples were collected monthly and during storms at a site near the stream's mouth (Chester Creek at Arctic Boulevard) and analyzed for major ions and nutrients. Water samples collected during water year 1999 were analyzed for selected pesticides and volatile organic compounds. Concentrations of fecal-indicator bacteria were determined monthly during calendar year 2000. During winter, spring, and summer, four water samples were collected at a site upstream of urban development (South Branch of South Fork Chester Creek at Tank Trail) and five from an intermediate site (South Branch of South Fork Chester Creek at Boniface Parkway). Concentrations of calcium, magnesium, sodium, chloride, and sulfate in water increased in the downstream direction. Nitrate concentrations were similar at the three sites and all were less than the drinking-water standard. About one-quarter of the samples from the Arctic Boulevard site had concentrations of phosphorus that exceeded the U.S. Environmental Protection Agency (USEPA) guideline for preventing nuisance plant growth. Water samples collected at the Arctic Boulevard site contained concentrations of the insecticide carbaryl that exceeded the guideline for protecting aquatic life. Every water sample revealed a low concentration of volatile organic compounds, including benzene, toluene, tetrachloroethylene, methyl tert-butyl ether, and chloroform. No water samples contained volatile organic compounds concentrations that exceeded any USEPA drinking-water standard or guideline. Fecal-indicator bacteria concentrations in water from the Arctic Boulevard site commonly exceeded Federal and State guidelines for water-contact recreation. Concentrations of cadmium, copper, lead, and zinc in streambed sediments increased in the downstream direction. Some concentrations of arsenic, chromium, lead, and zinc in sediments were at levels that can adversely affect aquatic organisms. Analysis of sediment chemistry in successive lakebed-sediment layers from Westchester Lagoon near the stream's mouth provided a record of water-quality trends since about 1970. Concentrations of lead have decreased from peak levels in the mid-1970s, most likely because of removing lead from gasoline and lower lead content in other products. However, concen-trations in recently-deposited lakebed sediments are still about 10 times greater than measured in streambed sediments at the upstream Tank Trail site. Zinc concentrations in lakebed sediments also increased in the early 1970s to levels that exceeded guidelines to protect aquatic life and have remained at elevated but variable levels. Pyrene, benz[a]anthracene, and phenanthrene in lakebed sediments also have varied in concentrations and have exceeded protection guidelines for aquatic life since the 1970s. Concentrations of dichloro-diphenyl-trichloroethane, polychlorinated biphenyls (PCBs), or their by-products generally were highest in lakebed sediments deposited in the 1970s. More recent sediments have concentrations that vary widely and do not show distinct temporal trends. Tissue samples of whole slimy sculpin (Cottus cognatus), a non-migratory species of fish, showed con-centrations of trace elements and organic contaminants. Of the constituents analyzed, only selenium concentra-tions showed levels of potential concern for

Natural Arsenic in the Miocene Hawthorn Group, Florida: Wide Ranging Implications for ASR, Phosphate Mining, Private Well

NASA Astrophysics Data System (ADS)

Lazareva, O. V.; Pichler, T.

2004-12-01

In order to understand the mineralogical association and distribution of arsenic (As) in the Hawthorn Group we examined in detail the chemical and mineralogical composition of 370 samples that were collected from 16 cores in central Florida. In our study area the Hawthorn group consists primarily of a basal carbonate unit (the Arcadia Formation) and an upper siliciclastic unit (The Peace River Formation). The Peace River Formation contains appreciable amounts of phosphate and is currently being exploited for phosphate ore. Samples were taken for each Formation at intervals of 25ft. In addition to the interval samples we also took samples that contained visible pyrite crystals, iron oxides, green clays, phosphatic and organic material. These additional samples were collected because of their potential of high As concentrations. Arsenic concentrations were determined by hydride generation - atomic fluorescence spectrometry (HG-AFS) after digestion with aqua regia (3:1 HCl and HNO3). The elements Fe, Na, Al, Si, Mg, Ca, S, P, and K were measured on the same solutions by inductively coupled plasma optical emission spectrometry (ICP-OES). The identification of discrete minerals was aided by scanning electron microscopy (SEM) and chemical compositions were obtained by electron-probe microanalyses (EMPA). Our study indicates that the average As concentrations significantly change from 9.0 ppm in the Peace River Formation to 3.0 ppm in the Tampa Member of the Arcadia Formation. As concentrations for all Hawthorn samples vary from 0.07 to 68.98 ppm ( μ = 5.6, σ = 7.1). Our detailed mineralogical and geochemical study demonstrates that: (1) The As in the Hawthorn group varies from the formation to formation and is mostly concentrated in trace minerals, such as pyrite; (2) Concentrations of the As in pyrite crystals can vary drastically from a minimum of 0 ppm to a maximum of 8260 ppm; (3) Pyrite is an unevenly distributed throughout the Hawthorn Group; (4) Phosphate and organic material, clays, and iron oxides contain lower As concentrations contrasted to pyrite; (5) Pyrite occurs in framboidal and euhedral forms. Because phosphorous, arsenic and sulfur are chemically closely related, they often occur together in nature, thus posing a potential problem for the phosphate industry. There have been several occurrences of swine fatalities due to arsenic poisoning as a result of phosphate feed supplements. Information about the concentration, distribution and mineralogical association of naturally occurring As is important, because this is a first step to forecast its behavior during anthropogenic induced physico-chemical changes in the aquifer. Recently, aquifer storage and recovery (ASR) facilities in central Florida reported As concentrations in excess of 100 μ g/L in recovered water. The ASR storage zone is the Suwannee Limestone, which directly underlies the Hawthorn sediments. It is crucial to the future of ASR in this area to understand the source and distribution of arsenic in the overlying Hawthorn Group and the cycling of arsenic in the Florida platform.

PIXE analysis of sand and soil from Ulaanbaatar and Karakurum, Mongolia

NASA Astrophysics Data System (ADS)

Markwitz, A.; Barry, B.; Shagjjamba, D.

2008-09-01

Twenty-one sand and soil samples were collected at the surface from 22 to 25 June 2007 at sampling sites from Ulaanbaatar to Karakurum, Mongolia. The sand samples were collected from constantly changing sand dunes which may still contain salt from prehistoric oceans. The dry sand and soil samples were processed for PIXE and PIGE analyses. A clear division between soils and sand become apparent in the silicon results. Concentrations of all bulk elements in human habitation samples and of Si, Al, K and Fe in dry lake/flood plain samples are similar to those in the soils and sands. Among elements which could be regarded as being at trace concentrations the average S concentration in the soils is 0.9 g kg-1 whereas it is not detected in the sand samples. Zinc and Cu concentrations are both higher in the soils than the sands and are strongly correlated. A surprising presence of uranium at a concentration of 350 mg kg-1 was detected in the PIXE measurement on one of the dry lake samples. Gamma spectrometry confirmed the presence of U in this sample and also at a lower level in a sample from the lake shore, but in none of the other samples. Further, the gamma spectrometry showed that 238U decay products were present only at a level corresponding to about 3 mg kg-1 U for a system in radioactive equilibrium, a figure which is typical for U in the earth's crust. Disequilibria between 238U and its decay products occur naturally but such a high degree of separation at high concentration would be unique if confirmed. PIXE and PIGE measurements of these samples highlight the difficulty in correlating trace element measurements with occurrence of indicators of sea salt in air particulate samples.

Effects of sample handling methods on substance P concentrations and immunoreactivity in bovine blood samples.

PubMed

Mosher, Ruby A; Coetzee, Johann F; Allen, Portia S; Havel, James A; Griffith, Gary R; Wang, Chong

2014-02-01

To determine the effects of protease inhibitors and holding times and temperatures before processing on the stability of substance P in bovine blood samples. Blood samples obtained from a healthy 6-month-old calf. Blood samples were dispensed into tubes containing exogenous substance P and 1 of 6 degradative enzyme inhibitor treatments: heparin, EDTA, EDTA with 1 of 2 concentrations of aprotinin, or EDTA with 1 of 2 concentrations of a commercially available protease inhibitor cocktail. Plasma was harvested immediately following collection or after 1, 3, 6, 12, or 24 hours of holding at ambient (20.3° to 25.4°C) or ice bath temperatures. Total substance P immunoreactivity was determined with an ELISA; concentrations of the substance P parent molecule, a metabolite composed of the 9 terminal amino acids, and a metabolite composed of the 5 terminal amino acids were determined with liquid chromatography-tandem mass spectrometry. Regarding blood samples processed immediately, no significant differences in substance P concentrations or immunoreactivity were detected among enzyme inhibitor treatments. In blood samples processed at 1 hour of holding, substance P parent molecule concentration was significantly lower for ambient temperature versus ice bath temperature holding conditions; aprotinin was the most effective inhibitor of substance P degradation at the ice bath temperature. The ELISA substance P immunoreactivity was typically lower for blood samples with heparin versus samples with other inhibitors processed at 1 hour of holding in either temperature condition. Results suggested that blood samples should be chilled and plasma harvested within 1 hour after collection to prevent substance P degradation.

Exposure of school children to polycyclic aromatic hydrocarbons, heavy metals and radionuclides in the urban soil of Kragujevac city, Central Serbia.

PubMed

Stajic, J M; Milenkovic, B; Pucarevic, M; Stojic, N; Vasiljevic, I; Nikezic, D

2016-03-01

The concentrations of radionuclides, polycyclic aromatic hydrocarbons (PAHs) and heavy metals were measured in soil samples collected from school backyards and playgrounds in Kragujevac, one of the largest cities of Central Serbia. The activity concentrations of (226)Ra, (232)Th, (40)K and (137)Cs were determined using the HPGe semiconductor detector. The average values were 34.6, 44.7, 428.9 and 45.1 Bq kg(-1), respectively. The correlation between the activity concentrations of (226)Ra in the soil samples and the results of the previous measurement of (222)Rn concentrations in the indoor air was examined. The absorbed dose rates, the annual effective doses and excess lifetime cancer risk were also estimated. The activity concentrations of (226)Ra and (232)Th have shown normal distribution. The collected soil samples were analysed for PAHs by HPLC. All analysed soil samples contained PAHs, and their total amounts (for 15 measured compounds) were found to be between 0.038 and 3.136 mg kg(-1) of absolutely dry soil (a.d.s). In addition the concentrations of As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn were measured in the fourteen soil samples collected from the playgrounds of kindergartens. Copyright © 2015 Elsevier Ltd. All rights reserved.

Environmental contaminants in surrogates, foods, and feathers of California condors (Gymnogyps californianus)

USGS Publications Warehouse

Wiemeyer, Stanley N.; Jurek, R.M.; Moore, John F.

1986-01-01

California condor (Gymnogyps californianus) foods and feathers, and turkey vultures (Cathartes aura), common ravens (Corvus corax), and their eggs were collected within the condor range to determine exposure of condors to environmental contaminants. Samples were analyzed for organochlorines and trace elements. Food items contained low concentrations of organochlorines and generally low concentrations of lead. DDE was detected in all vulture carcasses and nearly all raven carcasses at generally moderate concentrations. Other organochlorines occurred infrequently in carcasses and generally at low concentrations. Turkey vulture eggshells were 16% thinner than the pre-DDT mean; there was no change in shell thickness of raven eggs. Vulture eggs contained an average of 6.9 ppm DDE and two contained excessive concentrations of endrin. DDE concentrations were low in raven eggs. Residues of As, Cd, Cr, Cu, Fe, Hg, Ni, Se, Tl, and Zn in tissues of vultures and ravens appeared normal when compared with reference values for other species. Lead concentrations in bone of turkey vultures and feathers of condors appeared to be elevated above normal background concentrations in some cases. Current exposure of condors to organochlorines appears low; however, we are concerned about the excessive exposure of turkey vultures to organochlorines, possibly in Central America. Lead exposure to vultures and condors has occurred, but its significance to their populations is unknown.

User's guide for polyethylene-based passive diffusion bag samplers to obtain volatile organic compound concentrations in wells. Part I, Deployment, recovery, data interpretation, and quality control and assurance

USGS Publications Warehouse

Vroblesky, Don A.

2001-01-01

Diffusion samplers installed in observation wells were found to be capable of yielding representative water samples for chlorinated volatile organic compounds. The samplers consisted of polyethylene bags containing deionized water and relied on diffusion of chlorinated volatile organic compounds through the polyethylene membrane. The known ability of polyethylene to transmit other volatile compounds, such as benzene and toluene, indicates that the samplers can be used for a variety of volatile organic compounds. In wells at the study area, the volatile organic compound concentrations in water samples obtained using the samplers without prior purging were similar to concentrations in water samples obtained from the respective wells using traditional purging and sampling approaches. The low cost associated with this approach makes it a viable option for monitoring large observation-well networks for volatile organic compounds.

User's guide for polyethylene-based passive diffusion bag samplers to obtain volatile organic compound concentrations in wells. Part 2, Field tests

USGS Publications Warehouse

Vroblesky, Don A.

2001-01-01

Diffusion samplers installed in observation wells were found to be capable of yielding representative water samples for chlorinated volatile organic compounds. The samplers consisted of polyethylene bags containing deionized water and relied on diffusion of chlorinated volatile organic compounds through the polyethylene membrane. The known ability of polyethylene to transmit other volatile compounds, such as benzene and toluene, indicates that the samplers can be used for a variety of volatile organic compounds. In wells at the study area, the volatile organic compound concentrations in water samples obtained using the samplers without prior purging were similar to concentrations in water samples obtained from the respective wells using traditional purging and sampling approaches. The low cost associated with this approach makes it a viable option for monitoring large observation-well networks for volatile organic compounds.

Benefaction studies on the Hasan Celebi magnetite deposit, Turkey

USGS Publications Warehouse

Pressler, Jean W.; Akar, Ali

1972-01-01

Bench-scale and semicontinuous tests were performed on surface, trench, and diamond drill core samples from the Hasan Celebi low-grade magnetite deposit to determine the optimum benefication procedures utilizing wet magnetic separation techniques. Composite core samples typically contain about 27 percent recoverable magnetite and require crushing and grinding through 1 mm in size to insure satisfactory separation of the gangue from the magnetite. Regrinding and cleaning the magnetite concentrate to 80 percent minus 150-mesh is necessary to obtain an optimum of 66 percent iron. Semicontinuous pilot-plant testing with the wet magnetic drum using the recycled middling technique indicates that as much as 83 percent of the acid-soluble iron can be recovered into a concentrate containing 66 percent iron, with minimum deleterious elements. This represents 27 weight percent of the original ore. Further tests will continue when the Maden Tetkik ve Arama Enstitusu (MTA) receives 24 tons of bulk sample from an exploratory drift and cross-cut now being driven through a section of the major reserve area.

Occurrence of Pharmaceuticals in Shallow Ground-Water of Suffolk County, New York, 2002-05

USGS Publications Warehouse

Benotti, Mark J.; Fisher, Shawn; Terracciano, Stephen

2006-01-01

Seventy (70) water samples were collected from 61 wells in the upper glacial and Magothy aquifers (9 wells were sampled twice) during 2002-05 and analyzed for 24 pharmaceuticals. Wells were selected for their proximity to known wastewater-treatment facilities that discharge to the shallow upper glacial aquifer. Pharmaceuticals were detected in 28 of the 70 samples, 19 of which contained one compound, and 9 of which contained two or more compounds. Concentrations of detected compounds were extremely low; most ranged from 0.001 to 0.1 microgram per liter (part per billion). The two most commonly detected compounds were carbamazepine (an antiepileptic drug) and sulfamethoxazole (an antibiotic). Occurrence of pharmaceutical compounds in Suffolk County ground-water is less prevalent than in susceptible streams of the United States that were tested in 1998-2000, but the similarity of median concentrations of the detected compounds of the two data sets indicates that current wastewater practices can serve to introduce pharmaceuticals to this shallow aquifer.

Assessment of surface acidity in mesoporous materials containing aluminum and titanium

NASA Astrophysics Data System (ADS)

Araújo, Rinaldo S.; Maia, Débora A. S.; Azevedo, Diana C. S.; Cavalcante, Célio L., Jr.; Rodríguez-Castellón, E.; Jimenez-Lopez, A.

2009-04-01

The surface acidity of mesoporous molecular sieves of aluminum and titanium was evaluated using four different techniques: n-butylamine volumetry, cyclohexylamine thermodesorption, temperature-programmed desorption of ammonia and adsorption of pyridine. The nature, strength and concentration of the acid sites were determined and correlated to the results of a probe reaction of anthracene oxidation to 9,10-anthraquinone (in liquid phase). In general, the surface acidity was highly influenced by the nature, location and coordination of the metal species (Al and Ti) in the mesoporous samples. Moderate to strong Brönsted acid sites were identified for the Al-MCM-41 sample in a large temperature range. For mesoporous materials containing Ti, the acidity was represented by a combination of weak to moderate Brönsted and Lewis acid sites. The Ti-HMS sample exhibits a higher acidity of moderate strength together with a well-balanced concentration of Brönsted and Lewis acid sites, which enhanced both conversion and selectivity in the oxidation reaction of anthracene.

Mercury in ground water, septage, leach-field effluent, and soils in residential areas, New Jersey coastal plain

USGS Publications Warehouse

Barringer, J.L.; Szabo, Z.; Schneider, D.; Atkinson, W.D.; Gallagher, R.A.

2006-01-01

Water samples were collected from domestic wells at an unsewered residential area in Gloucester County, New Jersey where mercury (Hg) concentrations in well water were known to exceed the USEPA maximum contaminant level (MCL) of 2000 ng/L. This residential area (the CSL site) is representative of more than 70 such areas in southern New Jersey where about 600 domestic wells, sampled previously by State and county agencies, yielded water containing Hg at concentrations that exceed the MCL. Recent studies indicate that background concentrations of Hg in water from this unconfined sand and gravel aquifer system are < 10 ng/L. Additional sampling was conducted at the CSL site in order to better understand sources of Hg and potential Hg transport mechanisms in the areas with Hg-contaminated ground water. At the CSL site, concentrations of Hg were substantially lower (although still exceeding the MCL in some cases) in filtered water samples than in the unfiltered water samples collected previously from the same wells. Surfactants and elevated concentrations of sodium, chloride, nitrate, ammonium, and phosphate in water from domestic and observation wells indicated septic-system effects on water quality; detections of sulfide indicated localized reducing conditions. Hg concentrations in septage and leach-field effluent sampled at several other households in the region were low relative to the contaminant-level Hg concentrations in water from domestic wells. Relations of Hg concentrations in leach-field effluent to iron concentrations indicate that reductive dissolution of iron hydroxides in soils may release Hg to the percolating effluent. ?? 2005 Elsevier B.V. All rights reserved.

Airborne asbestos in public buildings

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

Chesson, J.; Hatfield, J.; Schultz, B.

The U.S. Environmental Protection Agency sampled air in 49 government-owned buildings (six buildings with no asbestos-containing material, six buildings with asbestos-containing material in generally good condition, and 37 buildings with damaged asbestos-containing material). This is the most comprehensive study to date of airborne asbestos levels in U.S. public buildings during normal building activities. The air outside each building was also sampled. Air samples were analyzed by transmission electron microscopy using a direct transfer preparation technique. The results show an increasing trend in average airborne asbestos levels; outdoor levels are lowest and levels in buildings with damaged asbestos-containing material are highest.more » However, the measured levels and the differences between indoors and outdoors and between building categories are small in absolute magnitude. Comparable studies from Canada and the UK, although differing in their estimated concentrations, also conclude that while airborne asbestos levels may be elevated in buildings that contain asbestos, levels are generally low. This conclusion does not eliminate the possibility of higher airborne asbestos levels during maintenance or renovation that disturbs the asbestos-containing material.« less

Speciation of arsenic in biological samples.

PubMed

Mandal, Badal Kumar; Ogra, Yasumitsu; Anzai, Kazunori; Suzuki, Kazuo T

2004-08-01

Speciation of arsenicals in biological samples is an essential tool to gain insight into its distribution in tissues and its species-specific toxicity to target organs. Biological samples (urine, hair, fingernail) examined in the present study were collected from 41 people of West Bengal, India, who were drinking arsenic (As)-contaminated water, whereas 25 blood and urine samples were collected from a population who stopped drinking As contaminated water 2 years before the blood collection. Speciation of arsenicals in urine, water-methanol extract of freeze-dried red blood cells (RBCs), trichloroacetic acid treated plasma, and water extract of hair and fingernail was carried out by high-performance liquid chromatography (HPLC)-inductively coupled argon plasma mass spectrometry (ICP MS). Urine contained arsenobetaine (AsB, 1.0%), arsenite (iAs(III), 11.3), arsenate (iAs(V), 10.1), monomethylarsonous acid (MMA(III), 6.6), monomethylarsonic acid (MMA(V), 10.5), dimethylarsinous acid (DMA(III), 13.0), and dimethylarsinic acid (DMA(V), 47.5); fingernail contained iAs(III) (62.4%), iAs(V) (20.2), MMA(V) (5.7), DMA(III) (8.9), and DMA(V) (2.8); hair contained iAs(III) (58.9%), iAs(V) (34.8), MMA(V) (2.9), and DMA(V) (3.4); RBCs contained AsB (22.5%) and DMA(V) (77.5); and blood plasma contained AsB (16.7%), iAs(III) (21.1), MMA(V) (27.1), and DMA(V) (35.1). MMA(III), DMA(III), and iAs(V) were not found in any plasma and RBCs samples, but urine contained all of them. Arsenic in urine, fingernails, and hair are positively correlated with water As, suggesting that any of these measurements could be considered as a biomarker to As exposure. Status of urine and exogenous contamination of hair urgently need speciation of As in these samples, but speciation of As in nail is related to its total As (tAs) concentration. Therefore, total As concentrations of nails could be considered as biomarker to As exposure in the endemic areas.

Changes in metal mobility associated with bark beetle-induced tree mortality.

PubMed

Mikkelson, Kristin M; Bearup, Lindsay A; Navarre-Sitchler, Alexis K; McCray, John E; Sharp, Jonathan O

2014-05-01

Recent large-scale beetle infestations have caused extensive mortality to conifer forests resulting in alterations to dissolved organic carbon (DOC) cycling, which in turn can impact metal mobility through complexation. This study analyzed soil-water samples beneath impacted trees in concert with laboratory flow-through soil column experiments to explore possible impacts of the bark beetle infestation on metal release and transport. The columns mimicked field conditions by introducing pine needle leachate and artificial rainwater through duplicate homogenized soil columns and measuring effluent metal (focusing on Al, Cu, and Zn) and DOC concentrations. All three metals were consistently found in higher concentrations in the effluent of columns receiving pine needle leachate. In both the field and laboratory, aluminum mobility was largely correlated with the hydrophobic fraction of the DOC, while copper had the largest correlation with total DOC concentrations. Geochemical speciation modeling supported the presence of DOC-metal complexes in column experiments. Copper soil water concentrations in field samples supported laboratory column results, as they were almost twice as high under grey phase trees than under red phase trees further signifying the importance of needle drop. Pine needle leachate contained high concentrations of Zn (0.1 mg l(-1)), which led to high effluent zinc concentrations and sorption of zinc to the soil matrix representing a future potential source for release. In support, field soil-water samples underneath beetle-impacted trees where the needles had recently fallen contained approximately 50% more zinc as samples from under beetle-impacted trees that still held their needles. The high concentrations of carbon in the pine needle leachate also led to increased sorption in the soil matrix creating the potential for subsequent carbon release. While unclear if manifested in adjacent surface waters, these results demonstrate an increased potential for Zn, Cu, and Al mobility, along with increased deposition of metals and carbon beneath beetle-impacted trees.

Determination of endogenous concentrations of nitrites and nitrates in different types of cheese in the United States: method development and validation using ion chromatography.

PubMed

Genualdi, Susan; Jeong, Nahyun; DeJager, Lowri

2018-04-01

Nitrites and nitrates can be present in dairy products from both endogenous and exogenous sources. In the European Union (EU), 150 mg kg - 1 of nitrates are allowed to be added to the cheese milk during the manufacturing process. The CODEX General Standard for Food Additives has a maximum permitted level of 50 mg kg - 1 residue in cheese, while in the United States (U.S.) nitrates are unapproved for use as food additives in cheese. In order to be able to investigate imported cheeses for nitrates intentionally added as preservatives and the endogenous concentrations of nitrates and nitrites present in cheeses in the U.S. marketplace, a method was developed and validated using ion chromatography with conductivity detection. A market sampling of cheese samples purchased in the Washington DC metro area was performed. In 64 samples of cheese, concentrations ranged from below the method detection limit (MDL) to 26 mg kg - 1 for nitrates and no concentrations of nitrites were found in any of the cheese samples above the MDL of 0.1 mg kg - 1 . A majority of the samples (93%) had concentrations below 10 mg kg - 1 , which indicate the presence of endogenous nitrates. The samples with concentrations above 10 mg kg - 1 were mainly processed cheese spread, which can contain additional ingredients often of plant-based origin. These ingredients are likely the cause of the elevated nitrate concentrations. The analysis of 12 additional cheese samples that are liable to the intentional addition of nitrates, 9 of which were imported, indicated that in this limited study, concentrations of nitrate in the U.S.-produced cheeses did not differ from those in imported samples.

Influence of storage conditions on in vitro stability of atrial natriuretic peptide and of anesthesia on plasma atrial natriuretic peptide concentration in cats.

PubMed

Heishima, Yasuhiro; Hori, Yasutomo; Chikazawa, Seishiro; Kanai, Kazutaka; Hoshi, Fumio; Itoh, Naoyuki

2016-08-01

OBJECTIVE To investigate the in vitro stability of atrial natriuretic peptide (ANP) in plasma samples under various storage conditions and the influence of anesthesia on plasma ANP concentration in cats. ANIMALS 1 cat with congestive heart failure and 5 healthy adult mixed-breed cats. PROCEDURES A plasma sample from the cat with heart failure was serially diluted, and dilutional parallelism of ANP concentration was evaluated. Plasma samples containing aprotinin or serum samples from the 5 healthy cats were kept at room temperature (27°C) for ≤ 12 hours. Plasma samples from the same healthy cats were stored at -70°, -20°, or 4°C for ≤ 14 days. Plasma samples were obtained from the healthy cats before and during isoflurane anesthesia. Plasma ANP concentrations were measured at a commercial laboratory by use of a human ANP chemiluminescence assay. RESULTS Intra- and interassay coefficients of variation were 1.5% and 2.5%, respectively, and dilutional parallelism was established. Although ANP concentration decreased by 82.4 ± 13.6% (mean ± SD) after sample storage for 12 hours at room temperature, this decrease was prevented by aprotinin. Plasma ANP concentrations were stable for 7 days at -20°C and for 14 days at -70°C. However, concentrations decreased markedly to 57.6 ± 6.9% at -20°C and to 18.0 ± 3.0% at 4°C after 14 days. Plasma ANP concentration decreased significantly in cats during anesthesia and was correlated with blood pressure. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that aprotinin should be added routinely in preparation of plasma samples from cats for measurement of ANP concentration, and those samples, if stored, should be frozen immediately at ≤ -20°C. General anesthesia or systemic blood pressure may affect plasma ANP concentration in cats.

Freeze-drying of tert-butyl alcohol/water cosolvent systems: effects of formulation and process variables on residual solvents.

PubMed

Wittaya-Areekul, S; Nail, S L

1998-04-01

The objective of this study was to identify significant formulation and processing variables affecting levels of tert-butyl alcohol (TBA) and isopropyl alcohol (IPA) in freeze-dried solids prepared from TBA/water cosolvent systems. The variables examined were the physical state of the solute (crystalline vs amorphous), initial TBA concentration, freezing rate, cake thickness, and the temperature and duration of secondary drying. Sucrose and glycine were used as models for noncrystallizing and crystallizing solutes, respectively. The TBA concentration above which eutectic crystallization takes place was determined by differential scanning calorimetry. Model formulations were subjected to extremes of freezing rate by either dipping in liquid nitrogen or by slowly freezing on the shelf of a freeze-dryer. Dynamics of solvent loss during secondary drying was determined by withdrawing samples as a function of time at different shelf temperatures using a thief system. On the basis of these studies, the most important determinant of residual TBA level is the physical state of the solute. Freeze-dried glycine contained very low levels of residual TBA (0.01-0.03%) regardless of freezing rate or initial TBA concentration. For freeze-dried sucrose, residual TBA levels were approximately 2 orders of magnitude higher and were significantly affected by initial TBA concentration and freezing rate. For the sucrose/TBA/water system, relatively low residual TBA levels were obtained when the initial TBA level was above the threshold concentration for eutectic crystallization of TBA, whereas samples freeze-dried from solutions containing TBA concentrations below this threshold contained significantly higher levels of TBA. Residual IPA levels increased continuously with initial concentration of TBA in the sucrose/TBA/water system. Formulations of sucrose/TBA/water which were frozen rapidly contained residual TBA levels which were approximately twice those measured in the same formulation after slow freezing and drying under the same conditions. For the sucrose/TBA/water system, the temperature and time of secondary drying had only minimal influence on residual TBA in the freeze-dried solid. At low initial TBA concentrations (2%), residual TBA increases with increased cake thickness, perhaps because of the influence of depth of fill on effective freezing rate.

Tritium environmental transport studies at TFTR

NASA Astrophysics Data System (ADS)

Ritter, P. D.; Dolan, T. J.; Longhurst, G. R.

1993-06-01

Environmental tritium concentrations will be measured near the Tokamak Fusion Test Reactor (TFTR) to help validate dynamic models of tritium transport in the environment. For model validation the database must contain sequential measurements of tritium concentrations in key environmental compartments. Since complete containment of tritium is an operational goal, the supplementary monitoring program should be able to glean useful data from an unscheduled acute release. Portable air samplers will be used to take samples automatically every 4 hours for a week after an acute release, thus obtaining the time resolution needed for code validation. Samples of soil, vegetation, and foodstuffs will be gathered daily at the same locations as the active air monitors. The database may help validate the plant/soil/air part of tritium transport models and enhance environmental tritium transport understanding for the International Thermonuclear Experimental Reactor (ITER).

Occurrence of the angiotensin-converting enzyme inhibiting tripeptides Val-Pro-Pro and Ile-Pro-Pro in different cheese varieties of Swiss origin.

PubMed

Bütikofer, U; Meyer, J; Sieber, R; Walther, B; Wechsler, D

2008-01-01

The contents of the 2 antihypertensive peptides Val-Pro-Pro (VPP) and Ile-Pro-Pro (IPP) were determined in 101 samples from 10 different Swiss cheese varieties using HPLC with subsequent triple mass spectrometry. In the category of extra hard and hard cheeses, the Protected Denomination of Origin cheeses Berner Alpkäse and Berner Hobelkäse, L'Etivaz à rebibes, Le Gruyère, Sbrinz, Emmentaler (organic and conventional) and in the category of semihard cheeses, the varieties Tilsiter, Appenzeller 1/4 fat and full fat, Tête de Moine, and Vacherin fribourgeois were screened in the study. The average concentration of the sum of VPP and IPP in the screened cheese varieties varied to a large extent, and substantial variations were obtained for individual samples within the cheese varieties. The lowest average concentration of the 2 tri-petides was found in L'Etivaz à rebibes (n = 3) at 19.1 mg/kg, whereas Appenzeller 1/4 fat (n = 4) contained the greatest concentration at 182.2 mg/kg. In individual samples, the total concentration of VPP and IPP varied between 1.6 and 424.5 mg/kg. With the exception of a 10-yr-old cheese, VPP was always present at greater concentrations than IPP. Milk pretreatment, cultures, scalding conditions, and ripening time were identified as the key factors influencing the concentration of these 2 naturally occurring bioactive peptides in cheese. The results of the present study show that various traditional cheese varieties contain, on average, similar concentrations of the 2 antihypertensive peptides to the recently developed fermented milk products with blood pressure-lowering property. This may serve as a basis for the development of a functional cheese with blood pressure-lowering property.

Mass extraction container closure integrity physical testing method development for parenteral container closure systems.

PubMed

Yoon, Seung-Yil; Sagi, Hemi; Goldhammer, Craig; Li, Lei

2012-01-01

Container closure integrity (CCI) is a critical factor to ensure that product sterility is maintained over its entire shelf life. Assuring the CCI during container closure (C/C) system qualification, routine manufacturing and stability is important. FDA guidance also encourages industry to develop a CCI physical testing method in lieu of sterility testing in a stability program. A mass extraction system has been developed to check CCI for a variety of container closure systems such as vials, syringes, and cartridges. Various types of defects (e.g., glass micropipette, laser drill, wire) were created and used to demonstrate a detection limit. Leakage, detected as mass flow in this study, changes as a function of defect length and diameter. Therefore, the morphology of defects has been examined in detail with fluid theories. This study demonstrated that a mass extraction system was able to distinguish between intact samples and samples with 2 μm defects reliably when the defect was exposed to air, water, placebo, or drug product (3 mg/mL concentration) solution. Also, it has been verified that the method was robust, and capable of determining the acceptance limit using 3σ for syringes and 6σ for vials. Sterile products must maintain their sterility over their entire shelf life. Container closure systems such as those found in syringes and vials provide a seal between rubber and glass containers. This seal must be ensured to maintain product sterility. A mass extraction system has been developed to check container closure integrity for a variety of container closure systems such as vials, syringes, and cartridges. In order to demonstrate the method's capability, various types of defects (e.g., glass micropipette, laser drill, wire) were created in syringes and vials and were tested. This study demonstrated that a mass extraction system was able to distinguish between intact samples and samples with 2 μm defects reliably when the defect was exposed to air, water, placebo, or drug product (3 mg/mL concentration) solution. Also, it was verified that the method showed consistent results, and was able to determine the acceptance limit using 3σ for syringes and 6σ for vials.

Nutritional value of Kejeik: a dry fish product of the Sudan.

PubMed

Hassan, Zahra M A; Sulieman, Abdel Moneim E; Elkhalifa, Elamin A

2014-10-01

Kejeik product samples were collected from two different locations in Sudan including Singah city (Blue Nile) and Kusti city (White Nile). The contents of protein, moisture, ash, fat, crude fiber and carbohydrates varied considerably and ranged between 63.52-78.06, 5.37-6.69, 5.78-11.8, 9.04-16.13, 0.55-1.34 and 0.59-1.61% respectively, in the various Kejeik samples. However, the production area has a non-significant effect in most of the chemical components. All Kejeik samples contained appreciable amounts of macro-minerals and the calcium was the highest in all samples. In addition, Kejeik samples contained most of the micro-minerals, however, Nawk and Ijl Kejeik collected from Singah contained the lowest concentrations of iron. The study concluded that Kejeik is a safe food with a highly nutritive value which is recommended to be utilized in Sudanese meals especially during shortage of protein and other nutrients sources.

Large-volume constant-concentration sampling technique coupling with surface-enhanced Raman spectroscopy for rapid on-site gas analysis

NASA Astrophysics Data System (ADS)

Zhang, Zhuomin; Zhan, Yisen; Huang, Yichun; Li, Gongke

2017-08-01

In this work, a portable large-volume constant-concentration (LVCC) sampling technique coupling with surface-enhanced Raman spectroscopy (SERS) was developed for the rapid on-site gas analysis based on suitable derivatization methods. LVCC sampling technique mainly consisted of a specially designed sampling cell including the rigid sample container and flexible sampling bag, and an absorption-derivatization module with a portable pump and a gas flowmeter. LVCC sampling technique allowed large, alterable and well-controlled sampling volume, which kept the concentration of gas target in headspace phase constant during the entire sampling process and made the sampling result more representative. Moreover, absorption and derivatization of gas target during LVCC sampling process were efficiently merged in one step using bromine-thiourea and OPA-NH4+ strategy for ethylene and SO2 respectively, which made LVCC sampling technique conveniently adapted to consequent SERS analysis. Finally, a new LVCC sampling-SERS method was developed and successfully applied for rapid analysis of trace ethylene and SO2 from fruits. It was satisfied that trace ethylene and SO2 from real fruit samples could be actually and accurately quantified by this method. The minor concentration fluctuations of ethylene and SO2 during the entire LVCC sampling process were proved to be < 4.3% and 2.1% respectively. Good recoveries for ethylene and sulfur dioxide from fruit samples were achieved in range of 95.0-101% and 97.0-104% respectively. It is expected that portable LVCC sampling technique would pave the way for rapid on-site analysis of accurate concentrations of trace gas targets from real samples by SERS.

Large-volume constant-concentration sampling technique coupling with surface-enhanced Raman spectroscopy for rapid on-site gas analysis.

PubMed

Zhang, Zhuomin; Zhan, Yisen; Huang, Yichun; Li, Gongke

2017-08-05

In this work, a portable large-volume constant-concentration (LVCC) sampling technique coupling with surface-enhanced Raman spectroscopy (SERS) was developed for the rapid on-site gas analysis based on suitable derivatization methods. LVCC sampling technique mainly consisted of a specially designed sampling cell including the rigid sample container and flexible sampling bag, and an absorption-derivatization module with a portable pump and a gas flowmeter. LVCC sampling technique allowed large, alterable and well-controlled sampling volume, which kept the concentration of gas target in headspace phase constant during the entire sampling process and made the sampling result more representative. Moreover, absorption and derivatization of gas target during LVCC sampling process were efficiently merged in one step using bromine-thiourea and OPA-NH 4 + strategy for ethylene and SO 2 respectively, which made LVCC sampling technique conveniently adapted to consequent SERS analysis. Finally, a new LVCC sampling-SERS method was developed and successfully applied for rapid analysis of trace ethylene and SO 2 from fruits. It was satisfied that trace ethylene and SO 2 from real fruit samples could be actually and accurately quantified by this method. The minor concentration fluctuations of ethylene and SO 2 during the entire LVCC sampling process were proved to be <4.3% and 2.1% respectively. Good recoveries for ethylene and sulfur dioxide from fruit samples were achieved in range of 95.0-101% and 97.0-104% respectively. It is expected that portable LVCC sampling technique would pave the way for rapid on-site analysis of accurate concentrations of trace gas targets from real samples by SERS. Copyright © 2017 Elsevier B.V. All rights reserved.

Can groundwater sampling techniques used in monitoring wells influence methane concentrations and isotopes?

PubMed

Rivard, Christine; Bordeleau, Geneviève; Lavoie, Denis; Lefebvre, René; Malet, Xavier

2018-03-06

Methane concentrations and isotopic composition in groundwater are the focus of a growing number of studies. However, concerns are often expressed regarding the integrity of samples, as methane is very volatile and may partially exsolve during sample lifting in the well and transfer to sampling containers. While issues concerning bottle-filling techniques have already been documented, this paper documents a comparison of methane concentration and isotopic composition obtained with three devices commonly used to retrieve water samples from dedicated observation wells. This work lies within the framework of a larger project carried out in the Saint-Édouard area (southern Québec, Canada), whose objective was to assess the risk to shallow groundwater quality related to potential shale gas exploitation. The selected sampling devices, which were tested on ten wells during three sampling campaigns, consist of an impeller pump, a bladder pump, and disposable sampling bags (HydraSleeve). The sampling bags were used both before and after pumping, to verify the appropriateness of a no-purge approach, compared to the low-flow approach involving pumping until stabilization of field physicochemical parameters. Results show that methane concentrations obtained with the selected sampling techniques are usually similar and that there is no systematic bias related to a specific technique. Nonetheless, concentrations can sometimes vary quite significantly (up to 3.5 times) for a given well and sampling event. Methane isotopic composition obtained with all sampling techniques is very similar, except in some cases where sampling bags were used before pumping (no-purge approach), in wells where multiple groundwater sources enter the borehole.

Stability of i.v. admixture containing metoclopramide, diphenhydramine hydrochloride, and dexamethasone sodium phosphate in 0.9% sodium chloride injection.

PubMed

Kintzel, Polly E; Zhao, Ting; Wen, Bo; Sun, Duxin

2014-12-01

The chemical stability of a sterile admixture containing metoclopramide 1.6 mg/mL, diphenhydramine hydrochloride 2 mg/mL, and dexamethasone sodium phosphate 0.16 mg/mL in 0.9% sodium chloride injection was evaluated. Triplicate samples were prepared and stored at room temperature without light protection for a total of 48 hours. Aliquots from each sample were tested for chemical stability immediately after preparation and at 1, 4, 8, 24, and 48 hours using liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. Metoclopramide, diphenhydramine hydrochloride, and dexamethasone sodium phosphate were selectively monitored using multiple-reaction monitoring. Samples were diluted differently for quantitation using three individual LC-MS/MS methods. To determine the drug concentration of the three compounds in the samples, three calibration curves were constructed by plotting the peak area or the peak area ratio versus the concentration of the calibration standards of each tested compound. Apixaban was used as an internal standard. Linearity of the calibration curve was evaluated by the correlation coefficient r(2). Constituents of the admixture of metoclopramide 1.6 mg/mL, diphenhydramine hydrochloride 2 mg/mL, and dexamethasone sodium phosphate 0.16 mg/mL in 0.9% sodium chloride injection retained more than 90% of their initial concentrations over 48 hours of storage at room temperature without protection from light. The observed variability in concentrations of these three compounds was within the limits of assay variability. An i.v. admixture containing metoclopramide 1.6 mg/mL, diphenhydramine hydrochloride 2 mg/mL, and dexamethasone sodium phosphate 0.16 mg/mL in 0.9% sodium chloride injection was chemically stable for 48 hours when stored at room temperature without light protection. Copyright © 2014 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

Concentration of trace elements on branded cigarette in Malaysia

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

Azman, Muhammad Azfar, E-mail: m-azfar@nuclearmalaysia.gov.my; Hamzah, Suhaimi; Rahman, Shamsiah Abdul

Tobacco is a plant that is used as a recreational drug since the beginning of its use by the Native Americans. Now with the development of the tobacco industry, smoking has become a norm for the public in Malaysia. Trace elements in plants are mostly due to the uptake processes from the soils into the roots of the plants. The concentration of the elements may also be influenced by the elements contained in the water and also fertilizers. This paper aim to analyze the concentration of the trace elements contained in the branded cigarettes sold in Malaysia by utilizing themore » neutron activation analysis. The tobaccos were taken out from the cigarettes. The collected samples were air dried and passed through 2 mm sieve. Instrumental Neutron Activation Analysis (NAA) has been used for the determination of trace elements. Samples were activated in the Nuclear Malaysia Triga Mark II reactor with a neutron flux of 2.0 x 10{sup 12} n cm{sup -2} s{sup -1}. The samples then were analyzed using ORTEC Gamma Spectrometer a co-axial n-type HPGe detector with resolution of 2.0 keV at 1332 keV and relative efficiency of 20%. The data obtained could help in assessing the concentration of the trace elements that complying with the standard limitation dose proposed by World Health Organization (WHO)« less

Speciation of cadmium and zinc with application to soil solutions

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

Holm, P.E.; Christensen, T.H.; Tjell, J.C.

1995-01-01

A two-part method has been developed for determination of Cd and Zn species in 50-mL soil solution samples containing low concentrations of Cd and Zn (1-10 {mu}g Cd L{sup -1} and 50-1000 {mu}g Zn L{sup -1}). The method uses two cation exchange resins (Amberlite CG 120 and Chelex 100) in a batch-column-batch procedure and relies on analytical determinations of Cd and Zn by graphite furnace atomic absorption spectrophotometry. The first part (batch) of the method allows determination of free divalent Cd{sup 2+} and Zn{sup 2+}. This part is experimentally sensitive to cation concentrations and ionic strength and these parameters shouldmore » be controlled during the experimental procedures. However, it is shown that Cd and Zn concentrations and pH do not influence the method. Speciations performed on samples containing chloride and sulfate were in accordance with theoretical calculations. The second part (column-batch) of the method operationally separates the complexed fraction into labile complexes, slowly labile complexes, and stable complexes. Chloro complexes were identified as labile complexes, while EDTA complexes were identified as stable complexes. The method works well with relatively small volumes of sample solutions and at low metal concentrations and may be useful in characterization of Cd and Zn in soil solutions. 12 refs., 6 figs., 3 tabs.« less

Asbestos-containing materials and airborne asbestos levels in industrial buildings in Korea.

PubMed

Choi, Sangjun; Suk, Mee-Hee; Paik, Nam Won

2010-03-01

Recently in Korea, the treatment of asbestos-containing materials (ACM) in building has emerged as one of the most important environmental health issues. This study was conducted to identify the distribution and characteristics of ACM and airborne asbestos concentrations in industrial buildings in Korea. A total of 1285 presumed asbestos-containing material (PACM) samples were collected from 80 workplaces across the nation, and 40% of the PACMs contained more than 1% of asbestos. Overall, 94% of the surveyed workplaces contained ACM. The distribution of ACM did not show a significant difference by region, employment size, or industry. The total ACM area in the buildings surveyed was 436,710 m2. Ceiling tile ACM accounted for 61% (267,093 m2) of the total ACM area, followed by roof ACM (32%), surfacing ACM (6.1%), and thermal system insulation (TSI). In terms of asbestos type, 98% of total ACM was chrysotile, while crocidolite was not detected. A comparison of building material types showed that the material with the highest priority for regular management is ceiling tile, followed by roof, TSI, and surfacing material. The average airborne concentration of asbestos sampled without disturbing in-place ACM was 0.0028 fibers/cc by PCM, with all measurements below the standard of recommendation for indoor air quality in Korea (0.01 fibers/cc).

Screening for toxic phorbol esters in jerky pet treat products using LC-MS.

PubMed

Nishshanka, Upul; Jayasuriya, Hiranthi; Chattopadhaya, Chaitali; Kijak, Philip J; Chu, Pak-Sin; Reimschuessel, Renate; Tkachenko, Andriy; Ceric, Olgica; De Alwis, Hemakanthi G

2016-05-01

Since 2007, the U.S. FDA's Center for Veterinary Medicine (CVM) has been investigating reports of pets becoming ill after consuming jerky pet treats. Jerky used in pet treats contains glycerin, which can be made from vegetable oil or as a byproduct of biodiesel production. Because some biodiesel is produced using oil from Jatropha curcas, a plant that contains toxic compounds including phorbol esters, CVM developed a liquid chromatography-mass spectrometry (LC-MS) screening method to evaluate investigational jerky samples for the presence of these toxins. Results indicated that the samples analyzed with the new method did not contain Jatropha toxins at or above the lowest concentration tested. Published by Elsevier B.V.

Solvent Hold Tank Sample Results for MCU-16-1247-1248-1249: August 2016 Monthly Sample

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

Fondeur, F. F.; Jones, D. H.

Savannah River National Laboratory (SRNL) received one set of Solvent Hold Tank (SHT) samples (MCU-16-1247-1248-1249), pulled on 08/22/2016 for analysis. The samples were combined and analyzed for composition. Analysis of the composite sample MCU-16-1247-1248-1249 indicated the Isopar™L concentration is above its nominal level (101%). The extractant (MaxCalix) and the modifier (CS-7SB) are 7% and 9 % below their nominal concentrations. The suppressor (TiDG) is 63% below its nominal concentration. This analysis confirms the solvent may require the addition of TiDG, and possibly of modifier and MaxCalix to restore then to nominal levels. Based on the current monthly sample, the levelsmore » of TiDG, Isopar™L, MaxCalix, and modifier are sufficient for continuing operation but are expected to decrease with time. Periodic characterization and trimming additions to the solvent are recommended. At the time of writing this report, A solvent trim batch containing TiDG, modifier and MaxCalix, was added to the SHT (October 2016) and expect the concentration of these components to be at their nominal values.« less

Characterization of air contaminants formed by the interaction of lava and sea water.

PubMed

Kullman, G J; Jones, W G; Cornwell, R J; Parker, J E

1994-05-01

We made environmental measurements to characterize contaminants generated when basaltic lava from Hawaii's Kilauea volcano enters sea water. This interaction of lava with sea water produces large clouds of mist (LAZE). Island winds occasionally directed the LAZE toward the adjacent village of Kalapana and the Hawaii Volcanos National Park, creating health concerns. Environmental samples were taken to measure airborne concentrations of respirable dust, crystalline silica and other mineral compounds, fibers, trace metals, inorganic acids, and organic and inorganic gases. The LAZE contained quantifiable concentrations of hydrochloric acid (HCl) and hydrofluoric acid (HF); HCl was predominant. HCl and HF concentrations were highest in dense plumes of LAZE near the sea. The HCl concentration at this sampling location averaged 7.1 ppm; this exceeds the current occupational exposure ceiling of 5 ppm. HF was detected in nearly half the samples, but all concentrations were <1 ppm Sulfur dioxide was detected in one of four short-term indicator tube samples at approximately 1.5 ppm. Airborne particulates were composed largely of chloride salts (predominantly sodium chloride). Crystalline silica concentrations were below detectable limits, less than approximately 0.03 mg/m3 of air. Settled dust samples showed a predominance of glass flakes and glass fibers. Airborne fibers were detected at quantifiable levels in 1 of 11 samples. These fibers were composed largely of hydrated calcium sulfate. These findings suggest that individuals should avoid concentrated plumes of LAZE near its origin to prevent over exposure to inorganic acids, specifically HCl.

Effect of antacid on the bioavailabiity of lithium carbonate.

PubMed

Goode, D L; Newton, D W; Ueda, C T; Wilson, J E; Wulf, B G; Kafonek, D

1984-01-01

The effect of an antacid on the bioavailability of lithium carbonate was determined in six healthy men in a crossover study. The volunteers were given single 300-mg doses of lithium carbonate alone and with 30 ml of an antacid containing aluminum and magnesium hydroxides with simethicone. Blood samples were collected at various times for 0-24 hours after each dose. The plasma samples were analyzed for lithium using a spectrophotometer, and bioavailability variables were calculated from plasma lithium concentration-time curves. There were no significant differences in peak plasma lithium concentration, time to peak concentration, area under the concentration-time curve from 0 to 24 hours, first-order absorption rate constant, and first-order elimination rate constant between the two treatments. Concurrent administration of antacids and lithium carbonate should not affect lithium blood concentrations.

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.

Short communication: Macrocyclic lactone residues in butter from Brazilian markets.

PubMed

Macedo, Fabio; Marsico, Eliane Teixeira; Conte-Júnior, Carlos Adam; de Almeida Furtado, Leonardo; Brasil, Taila Figueredo; Pereira Netto, Annibal Duarte

2015-06-01

Macrocyclic lactones (ML) are commonly used in drug formulations for the treatment of parasites in cattle. In Brazil, except for drugs (or formulations) with long-term (half-life) effects, ML are registered for use in bovines. Indiscriminate use of ML may result in the presence of residues in milk and dairy products due to their lipophilic properties and thermal stability. This study applied a method of liquid chromatography with fluorimetric detection, recently developed and validated for the determination of residues of abamectin, doramectin, ivermectin, and moxidectin in butter. The method was applied to 38 samples of commercial butter purchased in the metropolitan area of Rio de Janeiro, Brazil, between June and September 2013, analyzed in triplicate. Ivermectin was detected in 89.5% of the samples, with concentrations between 0.3 and 119.4 µg/kg; 76.3% of the samples contained doramectin (0.6 to 64.7 µg/kg) and 55.2% contained abamectin (0.7 to 4.5 µg/kg). Most butter samples (76.3%) contained residues of more than 1 ML; however, no residues of moxidectin were detected. The results showed a high incidence of the presence of avermectins in butter samples. Butter is not included in the Brazilian National Plan for Control of Residues and Contaminants in Animal Products. As ML residues concentrate in lipophilic compounds, butter and other fatty dairy products should be screened for the presence of ML residues. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Evaluation of Selected Nutrients and Contaminants in Distillers Grains from Ethanol Production in Texas.

PubMed

Lee, Kyung-Min; Herrman, Timothy J; Post, Lynn

2016-09-01

This article contains the results of the evaluation of distillers grain (DG) coproducts from different ethanol plants around the United States and supplemented in animal diets in Texas, based on samples analyzed from 2008 to 2014. The samples were assessed for concentration, occurrence, and prevalence of selected nutrients and contaminants. Protein and sulfur contents of DG were largely different between maize and sorghum coproducts, as well as wet distillers grain with solubles (WDGS) and dried distillers grain with solubles (DDGS), indicating a significant effect of grain feedstock and dry grind process stream on DG composition and quality. Salmonella was isolated in 4 DDGS samples of a total of 157 DG samples, a percentage (2.5%) that is lower than the percentage of Salmonella -positive samples found in other feed samples analyzed during the same period. A small amount of virginiamycin residue was found in 24 maize DDGS, 1 maize WDGS, and 2 sorghum DDGS samples of 242 samples in total. One sorghum DDGS sample of 168 DG samples was contaminated with animal protein prohibited for use in ruminant feed and was channeled to poultry feed. The concentrations of aflatoxin and fumonisin DG coproducts averaged 3.4 μg/kg and 0.7 mg/kg, respectively. Among contaminated maize DG samples, five DDGS samples for aflatoxin contained a higher concentration than the U.S. Food and Drug Administration (FDA) minimum action level of 20 μg/kg for use in animal feed, whereas no sample for fumonisin was found above the action level of 5 mg/kg. The study provides the most current results involving DG coproducts and associated hazards that will assist development of food safety plans required by the FDA in their September 2015 rule titled "Current Good Manufacturing Practice Hazard Analysis and Risk Based Preventive Controls for Food for Animals."

Influence of storage conditions on aluminum concentrations in serum, dialysis fluid, urine, and tap water.

PubMed

Wilhelm, M; Ohnesorge, F K

1990-01-01

The influence of storage temperature, vessel type, and treatment on alterations of aluminum (Al) concentrations in serum, urine, and dialysis fluid samples was studied at three different concentrations for each sample over an 18-month period. Furthermore, the influence of acidification on Al levels in tap water, urine, and dialysis fluid samples was studied over a four-month period. Al was measured by atomic absorption spectrometry. Sample storage in glass vessels was unsuitable, whereas only minor alterations of Al levels were observed with storage in polypropylene tubes, polystyrene tubes, and Monovettes. By using appropriate plastic containers, acid washing of the vessels showed no improvement. Frozen storage was superior compared with 4 degrees C, whereas storage at -80 degrees C offered no advantage compared with storage at -20 degrees C. Acidification of tap water samples was necessary to stabilize Al levels during storage. No striking effect of acidification on Al levels in urine and dialysis fluid samples was found. It is concluded that longterm storage of serum, urine, tap water, and dialysis fluid samples is possible if appropriate conditions are used.

Radiochemical sampling and analysis of shallow ground water and sediment at the BOMARC Missile Facility, east-central New Jersey, 1999-2000

USGS Publications Warehouse

Szabo, Zoltan; Zapecza, Otto S.; Oden, Jeannette H.; Rice, Donald E.

2005-01-01

A field sampling experiment was designed using low-flow purging with a portable pump and sample-collection equipment for the collection of water and sediment samples from observation wells screened in the Kirkwood-Cohansey aquifer system to determine radionuclide or trace-element concentrations for various size fractions. Selected chemical and physical characteristics were determined for water samples from observation wells that had not been purged for years. The sampling was designed to define any particulate, colloidal, and solution-phase associations of radionuclides or trace elements in ground water by means of filtration and ultrafiltration techniques. Turbidity was monitored and allowed to stabilize before samples were collected by means of the low-flow purging technique rather than by the traditional method of purging a fixed volume of water at high-flow rates from the observation well. A minimum of four water samples was collected from each observation well. The samples of water from each well were collected in the following sequence. (1) A raw unfiltered sample was collected within the first minutes of pumping. (2) A raw unfiltered sample was collected after at least three casing volumes of water were removed and turbidity stabilized. (3) A sample was collected after the water was filtered with a 0.45-micron filter. (4) A sample was collected after the water passed through a 0.45-micron filter and a 0.003-micron tangential-flow ultrafilter in sequence. In some cases, a fifth sample was collected after the water passed through a 0.45-micron filter and a 0.05-micron filter in sequence to test for colloids of 0.003 microns to 0.05 microns in size. The samples were analyzed for the concentration of manmade radionuclides plutonium-238 and -239 plus -240, and americium-241. The samples also were analyzed for concentrations of uranium-234, -235, and -238 to determine whether uranium-234 isotope enrichment (resulting from industrial processing) is present. A subset of samples was analyzed for concentrations of thorium-232, -230, and -228 to determine if thorium-228 isotope enrichment, also likely to result from industrial processing, is present. Concentrations of plutonium isotopes and americium-241 in the water samples were less than 0.1 picocurie per liter, the laboratory reporting level for these manmade radionuclides, with the exception of one americium-241 concentration from a filtered sample. A sequential split sample from the same well did not contain a detectable concentration of americium-241, however. Other filtered and unfiltered samples of water from the same well did not contain quantities of americium-241 nearly as high as 0.1 pCi/L. Therefore, the presence of americium-241 in a quantifiable concentration in water samples from this well could not be confirmed. Neither plutonium nor americium was detected in samples of settled sediment collected from the bottom of the wells. Concentrations of uranium isotopes (maximum of 0.05 and 0.08 picocuries per liter of uranium-238 and uranium-234, respectively) were measurable in unfiltered samples of turbid water from one well and in the settled bottom sediment from 6 wells (maximum concentrations of 0.25 and 0.20 picocuries per gram of uranium-238 and uranium-234, respectively). The uranium-234/uranium-238 isotopic ratio was near 1:1, which indicates natural uranium. The analytical results, therefore, indicate that no manmade radionuclide contamination is present in any of the well-bottom sediments, or unfiltered or filtered water samples from any of the sampled wells. No evidence of manmade radionuclide contamination was observed in the aquifer as settled or suspended particulates, colloids, or in the dissolved phase.

Ferrographic and spectrographic analysis of oil sampled before and after failure of a jet engine

NASA Technical Reports Server (NTRS)

Jones, W. R., Jr.

1980-01-01

An experimental gas turbine engine was destroyed as a result of the combustion of its titanium components. Several engine oil samples (before and after the failure) were analyzed with a Ferrograph as well as plasma, atomic absorption, and emission spectrometers. The analyses indicated that a lubrication system failure was not a causative factor in the engine failure. Neither an abnormal wear mechanism, nor a high level of wear debris was detected in the oil sample from the engine just prior to the test in which the failure occurred. However, low concentrations of titanium were evident in this sample and samples taken earlier. After the failure, higher titanium concentrations were detected in oil samples taken from different engine locations. Ferrographic analysis indicated that most of the titanium was contained in spherical metallic debris after the failure.

Recovery of intrinsic fluorescence from single-point interstitial measurements for quantification of doxorubicin concentration.

PubMed

Baran, Timothy M; Foster, Thomas H

2013-10-01

We developed a method for the recovery of intrinsic fluorescence from single-point measurements in highly scattering and absorbing samples without a priori knowledge of the sample optical properties. The goal of the study was to demonstrate accurate recovery of fluorophore concentration in samples with widely varying background optical properties, while simultaneously recovering the optical properties. Tissue-simulating phantoms containing doxorubicin, MnTPPS, and Intralipid-20% were created, and fluorescence measurements were performed using a single isotropic probe. The resulting spectra were analyzed using a forward-adjoint fluorescence model in order to recover the fluorophore concentration and background optical properties. We demonstrated recovery of doxorubicin concentration with a mean error of 11.8%. The concentration of the background absorber was recovered with an average error of 23.2% and the scattering spectrum was recovered with a mean error of 19.8%. This method will allow for the determination of local concentrations of fluorescent drugs, such as doxorubicin, from minimally invasive fluorescence measurements. This is particularly interesting in the context of transarterial chemoembolization (TACE) treatment of liver cancer. © 2013 Wiley Periodicals, Inc.

Determination of primary aromatic amines in cold water extract of coloured paper napkin samples by liquid chromatography-tandem mass spectrometry.

PubMed

Yavuz, Oguzhan; Valzacchi, Sandro; Hoekstra, Eddo; Simoneau, Catherine

2016-06-01

The aim of this study was the optimisation of a multi-analyte method for the analysis of primary aromatic amines (PAAs) from napkins in order to support official controls and food safety. We developed a UHPLC-MS/MS method for the simultaneous determination of 36 toxicologically relevant PAAs for paper and board. Good regression coefficients of the calibration curves in a range of 0.992-0.999 and reproducibilities in a range of 2.3-15% were obtained. Limits of detections (LODs) were in the range of 0.03-1.4 µg l(-1) and recoveries were in a range of 21-110% for all the amines. A total of 93 coloured paper napkin samples from different European countries were bought and extracted with water to determine the PAAs. The results showed that 42 of 93 samples contained at least one PAA. More than half of the detected PAAs are considered as toxic, carcinogenic or probably carcinogenic to humans by the International Agency for Research on Cancer (IARC), or are classified as such in the European Union legislation on chemicals. Summed concentrations of PAAs in seven samples were higher than 10 µg l(-1), the limit of summed PAA in the European Union plastic food contact material regulation. Also, eight PAAs, classified as Category 1A and 1B carcinogen in the European Union legislation of chemicals, were detected at concentrations higher than 2 µg l(-1), exceeding the limit proposed by the Federal Institute for Risk Assessment in Germany. Aniline (n = 14) was most frequently present in higher concentrations followed by o-toluidine, o-anisidine, 2,4-dimethylaniline and 4-aminoazobenzene. Red, orange, yellow and multicoloured paper napkins contained the highest concentrations of total PAAs (> 10 µg l(-1)). Although the European Union has not harmonised the legislation of paper and board materials and, thus, there is no specific migration limit for PAAs from paper napkins, the present study showed that coloured paper napkins can contain toxic and carcinogenic PAAs at concentrations that are relevant for monitoring.

The effects of water sample treatment, preparation, and storage prior to cyanotoxin analysis for cylindrospermopsin, microcystin and saxitoxin.

PubMed

Kamp, Lisa; Church, Jennifer L; Carpino, Justin; Faltin-Mara, Erin; Rubio, Fernando

2016-02-25

Cyanobacterial harmful algal blooms occur in freshwater lakes, ponds, rivers, and reservoirs, and in brackish waters throughout the world. The wide variety of cyanotoxins and their congeners can lead to frequent exposure of humans through consumption of meat, fish, seafood, blue-green algal products and water, accidental ingestion of contaminated water and cyanobacterial scum during recreational activities, and inhalation of cyanobacterial aerosols. Cyanotoxins can also occur in the drinking water supply. In order to monitor human exposure, sensitive analytical methods such as enzyme linked immunosorbent assay and liquid chromatography-mass spectrometry are often used. Regardless of the analytical method of choice, some problems regularly occur during sample collection, treatment, storage, and preparation which cause toxin loss and therefore underestimation of the true concentration. To evaluate the potential influence of sample treatment, storage and preparation materials on surface and drinking water samples, the effects of different types of materials on toxin recovery were compared. Collection and storage materials included glass and various types of plastics. It was found that microcystin congeners LA and LF adsorbed to polystyrene, polypropylene, high density polyethylene and polycarbonate storage containers, leading to low recoveries (<70%), cylindrospermopsin and saxitoxin did not adsorb to the containers tested. Therefore, this study shows that glass or polyethylene terephthalate glycol containers are the materials of choice for collection and storage of samples containing the cyanotoxins cylindrospermopsin, microcystins, and saxitoxin. This study also demonstrated that after 15 min chlorine decreased the concentration of microcystin LR to <40%, microcystin LA and saxitoxin to <15%, therefore quenching of drinking water samples immediately upon sample collection is critical for accurate analysis. In addition, the effect of various drinking water treatment chemicals on toxin recovery and the behavior of those chemicals in the enzyme linked immunosorbent assays were also studied and are summarized. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Evaluation of Electronic Cigarette Liquids and Aerosol for the Presence of Selected Inhalation Toxins

PubMed Central

Kistler, Kurt A.; Gillman, Gene; Voudris, Vassilis

2015-01-01

Introduction: The purpose of this study was to evaluate sweet-flavored electronic cigarette (EC) liquids for the presence of diacetyl (DA) and acetyl propionyl (AP), which are chemicals approved for food use but are associated with respiratory disease when inhaled. Methods: In total, 159 samples were purchased from 36 manufacturers and retailers in 7 countries. Additionally, 3 liquids were prepared by dissolving a concentrated flavor sample of known DA and AP levels at 5%, 10%, and 20% concentration in a mixture of propylene glycol and glycerol. Aerosol produced by an EC was analyzed to determine the concentration of DA and AP. Results: DA and AP were found in 74.2% of the samples, with more samples containing DA. Similar concentrations were found in liquid and aerosol for both chemicals. The median daily exposure levels were 56 μg/day (IQR: 26–278 μg/day) for DA and 91 μg/day (IQR: 20–432 μg/day) for AP. They were slightly lower than the strict NIOSH-defined safety limits for occupational exposure and 100 and 10 times lower compared with smoking respectively; however, 47.3% of DA and 41.5% of AP-containing samples exposed consumers to levels higher than the safety limits. Conclusions: DA and AP were found in a large proportion of sweet-flavored EC liquids, with many of them exposing users to higher than safety levels. Their presence in EC liquids represents an avoidable risk. Proper measures should be taken by EC liquid manufacturers and flavoring suppliers to eliminate these hazards from the products without necessarily limiting the availability of sweet flavors. PMID:25180080

Identification of long-chain perfluorinated acids in biota from the Canadian Arctic.

PubMed

Martin, Jonathan W; Smithwick, Marla M; Braune, Birgit M; Hoekstra, Paul F; Muir, Derek C G; Mabury, Scott A

2004-01-15

Recently it was discovered that humans and animals from various urban and remote global locations contained a novel class of persistent fluorinated contaminants, the most pervasive of which was perfluorooctane sulfonate (PFOS). Lower concentrations of perfluorooctanoate, perfluorohexane sulfonate, and heptadecafluorooctane sulfonamide have also been detected in various samples. Although longer perfluoroalkyl carboxylates (PFCAs) are used in industry and have been detected in fish following a spill of aqueous film forming foam, no studies have been conducted to examine the widespread occurrence of long-chain PFCAs (e.g., CF3(CF2)xCOO-, where x > 6). To provide a preliminary assessment of fluorinated contaminants, including PFCAs, in the Canadian Arctic, polar bears, ringed seals, arctic fox, mink, common loons, northern fulmars, black guillemots, and fish were collected at various locations in the circumpolar region. PFOS was the major contaminant detected in most samples and in polar bear liver was the most prominent organohalogen (mean PFOS = 3.1 microg/g wet weight) compared to individual polychlorinated biphenyl congeners, chlordane, or hexachlorocyclohexane-related chemicals in fat. Using two independent mass spectral techniques, it was confirmed that all samples also contained ng/g concentrations of a homologous series of PFCAs, ranging in length from 9 to 15 carbons. Sum concentrations of PFCAs (sum(PFCAs)) were lower than total PFOS equivalents (sum(PFOS)) in all samples except for mink. In mink, perfluorononanoate (PFNA) concentrations exceeded PFOS concentrations, indicating that PFNA and other PFCAs should be considered in future risk assessments. Mammals feeding at higher trophic levels had greater concentrations of PFOS and PFCAs than mammals feeding at lower trophic positions. In general, odd-length PFCAs exceeded the concentration of even-length PFCAs, and concentrations decreased with increasing chain length in mammals. PFOS and PFCA concentrations were much lower for animals living in the Canadian Arctic than for the same species living in mid-latitude regions of the United States. Future studies should continue to monitor all fluorinated contaminants and examine the absolute and relative toxicities for this novel suite of PFCAs.

Extraction Efficiency of Different Solvents and LC-UV Determination of Biogenic Amines in Tea Leaves and Infusions

PubMed Central

Spizzirri, U. Gianfranco; Picci, Nevio

2016-01-01

Biogenic amines (BAs), that is, spermine, spermidine, putrescine, histamine, tyramine, β-phenylethylamine, cadaverine, and serotonin, have been determined in several samples of tea leaves, tea infusions, and tea drinks by LC-UV method after derivatization with dansyl chloride. Different extraction solvents have been tested and TCA 5% showed better analytical performances in terms of linearity, recovery percentages, LOD, LOQ, and repeatability than HCl 0.1 M and HClO4 0.1 M and was finally exploited for the quantitative determination of BAs in all samples. In tea leaves total BAs concentration ranged from 2.23 μg g−1 to 11.24 μg g−1 and PUT (1.05–2.25 μg g−1) and SPD (1.01–1.95 μg g−1) were always present, while SER (nd–1.56 μg g−1), HIS (nd–2.44 μg g−1), and SPM (nd–1.64 μg g−1) were detected more rarely. CAD and PHE were determined in few samples at much lower concentrations while none of the samples contained TYR. Tea infusions showed the same trend with total BAs concentrations never exceeding 80.7 μg L−1. Black teas showed higher amounts of BAs than green teas and organic and decaffeinated samples always contained much lower BAs levels than their conventional counterparts. PMID:27555979

Chemical fingerprinting identifies Echium vulgare, Eupatorium cannabinum and Senecio spp. as plant species mainly responsible for pyrrolizidine alkaloids in bee-collected pollen.

PubMed

Kast, Christina; Kilchenmann, Verena; Reinhard, Hans; Droz, Benoit; Lucchetti, Matteo Angelo; Dübecke, Arne; Beckh, Gudrun; Zoller, Otmar

2018-02-01

Various studies have shown that bee-collected pollen sold as nutritional supplements may contain toxic pyrrolizidine alkaloids (PAs) and, thus, pose a potential health risk for consumers. The level of contamination may vary according to its geographical and botanical origin. Here, the PA content of pollen produced in Switzerland was studied and 32 commercially available bee-collected pollen supplements produced between 2010 and 2014 were analysed. In addition, at what time period bees collect PA-containing pollen was investigated. Hence, this study looked into the occurrence of PAs in pollen samples collected daily during two-to-three consecutive seasons. Furthermore, the PA spectrum in pollen was compared to the spectrum found in flower heads of PA-plants to unambiguously identify plants responsible for PA contamination of pollen. The PA concentration of commercial and daily collected pollen was determined by target analysis using an HPLC-MS/MS system, allowing the detection of 18 different PAs and PA N-oxides found in the genera Echium, Eupatorium and Senecio, while the comparison of the PA spectrum in pollen and flower heads was performed by LC-HR-MS, allowing the detection of all PA types in a sample, including saturated, non-carcinogenic PAs. Of the commercially available pollen, 31% contained PAs with a mean concentration of 319 ng/g, mainly Echium- and Eupatorium-type PAs, while the PA concentrations were below the limit of quantitation (LOQ) in 69% of the pollen samples. Bees collected pollen containing Echium-type PAs mainly in June and July, while they gathered pollen containing Eupatorium-type PAs from mid-July to August. Senecio-type PAs appeared from June to September. Comparison of the PA array in pollen and plants identified E. vulgare and E. cannabinum as the main plants responsible for PA contamination of Swiss bee-collected pollen, and to a lesser extent also identified plants belonging to the genus Senecio.

Analyses and description of soil samples from Mountain Lake and Peters Mountain Wilderness Study areas, Virginia and West Virginia

USGS Publications Warehouse

Motooka, J.M.; Curtis, Craig A.; Lesure, Frank Gardner

1978-01-01

Semiquantitative emission spectrographic analyses for 30 elements and atomic absorption analysis for zinc on 98 soil samples are reported here in detail. Location for all samples are in Universal Transverse Mercator (UTM) coordinates. A few samples of soil developed on Lower Devonian sandstone and chert contain more barium and zinc than soils on other formations but do not suggest the occurrence of economic concentrations of either element.

A diurnal component to the variation in sieve tube amino acid content in wheat.

PubMed

Gattolin, Stefano; Newbury, H John; Bale, Jeffrey S; Tseng, Hua-Ming; Barrett, David A; Pritchard, Jeremy

2008-06-01

We have used high-sensitivity capillary electrophoresis coupled to a laser-induced fluorescence detection method to quantify 16 amino acids in wheat (Triticum aestivum) sieve tube (ST) samples as small as 2 nL collected by severing the stylets of feeding aphids. The sensitivity of the method was sufficient to determine a quantitative amino acid profile of individual STs without the need to bulk samples to produce larger volumes for analysis. This allowed the observation of the full range of variation that exists in individual STs. Some of the total concentrations of amino acids recorded are higher than those reported previously. The results obtained show variation in the concentrations of phenylalanine (Phe), histidine/valine (His/Val), leucine/isoleucine (Leu/Ile), arginine, asparagine, glutamine, tyrosine (Tyr), and lysine (Lys) across the ST samples. These could not be explained by plant-to-plant variation. Statistical analyses revealed five analytes (Tyr, Lys, Phe, His/Val, and Leu/Ile) that showed striking covariation in their concentrations across ST samples. A regression analysis revealed a significant relationship between the concentrations of Tyr, Lys, Phe, Leu/Ile, His/Val, asparagine, arginine, and proline and the time of collection of ST samples, with these amino acids increasing in concentration during the afternoon. This increase was confirmed to occur in individual STs by analyzing samples obtained from stylet bundles exuding for many hours. Finally, an apparent relationship between the exudation rate of ST sap and its total amino acid concentration was observed: samples containing higher total amino acid concentrations were observed to exude from the severed stylet bundles more slowly.

Roundup Ready soybean gene concentrations in field soil aggregate size classes.

PubMed

Levy-Booth, David J; Gulden, Robert H; Campbell, Rachel G; Powell, Jeff R; Klironomos, John N; Pauls, K Peter; Swanton, Clarence J; Trevors, Jack T; Dunfield, Kari E

2009-02-01

Roundup Ready (RR) soybeans containing recombinant Agrobacterium spp. CP4 5-enol-pyruvyl-shikimate-3-phosphate synthase (cp4 epsps) genes tolerant to the herbicide glyphosate are extensively grown worldwide. The concentration of recombinant DNA from RR soybeans in soil aggregates was studied due to the possibility of genetic transformation of soil bacteria. This study used real-time PCR to examine the concentration of cp4 epsps in four field soil aggregate size classes (>2000 microm, 2000-500 microm, 500-250 microm and <250 microm). Aggregates over 2000 microm in diameter had significantly greater gene concentrations than those with diameters under 2000 microm. The >2000 mum fraction contained between 66.62% and 99.18% of total gene copies, although it only accounted for about 30.00% of the sampled soil. Aggregate formation may facilitate persistence of recombinant DNA.

Determination of low-molecular-weight amines and ammonium in saline waters by ion chromatography after their extraction by steam distillation.

PubMed

Ferreira, Fernanda Nunes; Afonso, Julio Carlos; Pontes, Fernanda Veronesi Marinho; Carneiro, Manuel Castro; Neto, Arnaldo Alcover; Tristão, Maria Luiza Bragança; Monteiro, Maria Inês Couto

2016-04-01

A new method was developed for the determination of ammonium ion, monomethylamine and monoethylamine in saline waters by ion chromatography. Steam distillation was used to eliminate matrix interferences. Variables such as distillation time, concentration of sodium hydroxide solution and analyte mass were optimized by using a full two-level factorial (2(3) ) design. The influence of steam distillation on the analytical curves prepared in different matrices was also investigated. Limits of detection of 0.03, 0.05 and 0.05 mg/L were obtained for ammoniumion, monomethylamine and monoethylamine, respectively. Saline water samples from the Brazilian oil industry, containing sodium and potassium concentrations between 2.0-5.2% w/v and 96-928 mg/L, respectively, were analyzed. Satisfactory recoveries (90-105%) of the analytes were obtained for all spiked samples, and the precision was ≤ 7% (n = 3). The proposed method is adequate for analyzing saline waters containing sodium to ammoniumion, monomethylamine and monoethylamine concentration ratios up to 28 000:1 and potassium to ammonium, monomethylamine and monoethylamine concentration ratios up to 12 000:1. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Xylitol concentrations in artificial saliva after application of different xylitol dental varnishes

PubMed Central

PEREIRA, Agnes de Fátima Faustino; da SILVA, Thiago Cruvinel; da SILVA, Thelma Lopes; CALDANA, Magali de Lourdes; BASTOS, José Roberto Magalhães; BUZALAF, Marília Afonso Rabelo

2012-01-01

Objective The present study analyzed xylitol concentrations in artificial saliva over time after application of varnishes containing 10% and 20% xylitol. Material and Methods Fifteen bovine enamel specimens (8x4 mm) were randomly allocated to 3 groups (n=5/group), according to the type of varnish used: 10% xylitol, 20% xylitol and no xylitol (control). After varnish application (4 mg), specimens were immersed in vials containing 500 µL of artificial saliva. Saliva samples were collected in different times (1, 8, 12, 16, 24, 48 and 72 h) and xylitol concentrations were analyzed. Data were assessed by two-way repeated-measures ANOVA (p<0.05). Results Colorimetric analysis was not able to detect xylitol in saliva samples of the control group. Salivary xylitol concentrations were significantly higher up to 8 h after application of the 20% xylitol varnish. Thereafter, the 10% xylitol varnish released larger amounts of that polyol in artificial saliva. Conclusions Despite the results in short-term, sustained xylitol releases could be obtained when the 10% xylitol varnish was used. These varnishes seem to be viable alternatives to increase salivary xylitol levels, and therefore, should be clinically tested to confirm their effectiveness. PMID:22666828

DITT: a computer program for Data Interpretation for Torsional Tests

USGS Publications Warehouse

Chen, Albert T.F.

1979-01-01

Measurements of the helium concentration of soil samples collected and stored in Vacutainer-brand evacuated glass tubes show that Vacutainers are reliable containers for soil collection. Within the limits of reproducibility, helium content of soils appears to be independent of variations in soil temperature, barometric pressure, and quantity of soil moisture present in the sample.

Neutron attenuation characteristics of polyethylene, polyvinyl chloride, and heavy aggregate concrete and mortars.

PubMed

Abdul-Majid, S; Othman, F

1994-03-01

Polyethylene and polyvinyl chloride pellets were introduced into concrete to improve its neutron attenuation characteristics while several types of heavy coarse aggregates were used to improve its gamma ray attenuation properties. Neutron and gamma ray attenuation were studied in concrete samples containing coarse aggregates of barite, pyrite, basalt, hematite, and marble as well as polyethylene and polyvinyl chloride pellets in narrow-beam geometry. The highest neutron attenuation was shown by polyethylene mortar, followed by polyvinyl chloride mortar; barite and pyrite concrete showed higher gamma ray attenuation than ordinary concrete. Broad-beam and continuous (infinite) medium geometries were used to study the neutron attenuation of samples containing polymers at different concentrations with and without heavy aggregates, the fitting equations were established, and from these the neutron removal coefficients were deduced. In a radiation field of neutrons and gamma rays, the appropriate concentration of polymer and heavy aggregate can be selected to give the optimum total dose attenuation depending on the relative intensities of each type of radiation. This would give much better design flexibility over ordinary concrete. The compressive strength tests performed on mortar and concrete samples showed that their value, in general, decreases as polymer concentration increases and that the polyvinyl chloride mortar showed higher values than the polyethylene mortar. For general construction purposes, the compression strength was considered acceptable in these samples.

Microbiological and biochemical characteristics of ground beef as affected by gamma irradiation, food additives and edible coating film

NASA Astrophysics Data System (ADS)

Ouattara, B.; Giroux, M.; Yefsah, R.; Smoragiewicz, W.; Saucier, L.; Borsa, J.; Lacroix, M.

2002-03-01

The current interest in "minimally processed foods" has attracted the attention for combination of mild treatments to improve food safety and shelf-life extention. The present study was conducted to evaluate the combined effect of gamma irradiation and incorporation of naturally occurring antimicrobial compounds on microbial and biochemistry characteristics of ground beef. Ground beef patties (23% fat ) were purchased from a local grocery store (IGA, Laval, Que., Canada) and divided into 3 separate treatment groups: (i) control (ground beef without additive), (ii) ground beef with 0.5% (w/w) ascorbic acid, and (iii) ground beef with 0.5% ascorbic acid and coated with a protein-based coating containing selected spices. Samples were irradiated at 0, 1, 2, and 3 kGy final dose at the CIC. Samples were stored at 4°C and evaluated periodically for microbial growth, total thiobarbituric reactive substances (TBARS) and free sulfydryl content. At the end of the storage period, Enterobacteriaceae, Lactic acid bacteria, Pseudomonas and Brochothrix thermosphacta were enumerated. Regardless of the treatment group, irradiation significantly ( p⩽0.05) reduced the total aerobic plate counts (APC). Irradiation doses of 1, 2, and 3 kGy produced immediate reduction of 2, 3, and 4 log units of APCs, respectively. Also, shelf-life periods were higher for ground beef samples containing food additives. Lactic acid bacteria and Brochothrix thermosphacta were more resistant to irradiation than Enterobacteriaceae and Pseudomonas. Concentration of TBARS and free sulfydryl concentrations were stabilized during post-irradiation storage for samples containing ascorbic acid and coated with the protein-based coating containing spices.

Characterization of organic matter in cloud waters sampled at the puy de Dôme mountain using FT-ICR-MS

NASA Astrophysics Data System (ADS)

Bianco, A.; Chaumerliac, N.; Vaitilingom, M.; Deguillaume, L.; Bridoux, M. C.

2017-12-01

The chemical composition of organic matter in cloud water is highly complex. The organic species result from their dissolution from the gas phase or from the soluble fraction of the particle phase. They are also produced by aqueous phase reactivity. Several low molecular weight organic species have been quantified such as aldehydes and carboxylic acids. Recently, amino acids were also detected in cloud water and their presence is related to the presence of microorganisms. Compounds presenting similarities with high molecular weight organic substances or HULIS found in aerosols were also observed in clouds. Overall, these studies mainly focused on individual compounds or functional groups rather than the complex mixture at the molecular level. This study presents a non-targeted approach to characterize the organic matter in clouds. Samples were collected at the puy de Dôme Mountain (France). Two cloud water samples (June & July 2016) were analyzed using high resolution mass spectrometry (ESI-FT-ICR-MS 9.4T). A reversed solid phase extraction (SPE) procedure was performed to concentrate dissolved organic matter components. Composer (v.1.5.3) software was used to filter the mass spectral data, recalibrate externally the dataset and calculate all possible formulas for detected anions. The first cloud sample (June) resulted from air mass coming from the North (North Sea) while the second one (July) resulted from air mass coming from the West (Atlantic Ocean). Thus, both cloud events derived from marine air masses but were characterized by different hydrogen peroxide concentration and dissolved organic carbon content and were sampled at different periods during the day. Elemental compositions of 6487 and 3284 unique molecular species were identified in each sample. Nitrogen-containing compounds (CHNO compounds), sulfur-containing compounds (CHOS & CHNOS compounds) and other oxygen-containing compounds (CHO compounds) with molecular weights up to 800 Da were detected. The main class is CHNO (53% for both samples) while sulfur-containing compounds represent for the two samples respectively 21 & 14% of the total assigned molecular formulas. CHO compounds molecular formulas are respectively 25 & 32%. Among the two samples, only 2490 molecular formulas were found common to the two samples.

Nitrate Contamination in the groundwater of the Lake Acıgöl Basin, SW Turkey

NASA Astrophysics Data System (ADS)

Karaman, Muhittin; Budakoǧlu, Murat; Taşdelen, Suat

2017-04-01

The lacustrine Acıgöl basin, formed as an extensional half-graben, hosts various bodies of water, such as cold-hot springs, lakes, streams, and wells. The hydrologically closed basin contains a hypersaline lake (Lake Acıgöl) located in the southern part of the basin. The brackish springs and deep waters discharged along the Acıgöl fault zone in the southern part of the basin feed the hypersaline lake. Groundwater is used as drinking, irrigation, and domestic water in the closed Acıgöl Basin. Groundwater flows into the hypersaline lake from the highland. The Acıgöl basin hosts large plains (Hambat, Başmakçı, and Evciler). Waters in agricultural areas contain high amounts of nitrate; groundwater samples in agricultural areas contain nitrate levels higher than 10 mg/L. Nitrate concentrations in the groundwater samples varied from 0 to 487 mg/L (n=165); 25.4 % of the groundwater samples from the basin had nitrate concentrations above 10 mg/L (the WHO drinking guideline) and 52.2% of the groundwater samples from the basin had nitrate concentrations above 3.0 mg/L, and these high values were regarded as the result of human activity. The highest nitrate values were measured in the Hambat plain (480 and 100 mg/L) and Yirce Pinari spring (447 mg/L), which discharges along the Acıgöl fault zone in the southern part of the basin. The average multi-temporal nitrate concentration of the Yirce Pınarı spring was 3.3 mg/L. Extreme nitrate values were measured in the Yirce Pınarı spring during periods when sheep wool was washed (human activity). The lowest nitrate concentrations were observed in some springs that discharged along the Acıgöl fault zone in the southern part of the basin. Nitrate was not detected in deep groundwater discharged along the Acıgöl fault zone. Nitrate concentrations in deep groundwater and some springs discharged along the Acıgöl fault zone and those feeding the hypersaline lake were significantly affected by redox conditions. Nitrate in these reducing waters was transformed into ammonium. Nitrate concentrations in the Acıgöl Basin were enriched in groundwater beneath agricultural areas and this affected redox conditions. The main source of nitrate contamination was agricultural fertilizers. Elevated nitrate concentrations in groundwater, especially in agricultural areas of the Acigol Basin, can cause public health problems and environmental pollution.

Effects of acid-volatile sulfide on metal bioavailability and toxicity to midge (Chironomus tentans) larvae in black shale sediments

USGS Publications Warehouse

Ogendi, G.M.; Brumbaugh, W.G.; Hannigan, R.E.; Farris, J.L.

2007-01-01

Metal bioavailability and toxicity to aquatic organisms are greatly affected by variables such as pH, hardness, organic matter, and sediment acid-volatile sulfide (AVS). Sediment AVS, which reduces metal bioavailability and toxicity by binding and immobilizing metals as insoluble sulfides, has been studied intensely in recent years. Few studies, however, have determined the spatial variability of AVS and its interaction with simultaneously extracted metals (SEM) in sediments containing elevated concentrations of metals resulting from natural geochemical processes, such as weathering of black shales. We collected four sediment samples from each of four headwater bedrock streams in northcentral Arkansa (USA; three black shale-draining streams and one limestone-draining stream). We conducted 10-d acute whole-sediment toxicity tests using the midge Chironomus tentans and performed analyses for AVS, total metals, SEMs, and organic carbon. Most of the sediments from shale-draining streams had similar total metal and SEM concentrations but considerable differences in organic carbon and AVS. Zinc was the leading contributor to the SEM molar sum, averaging between 68 and 74%, whereas lead and cadmium contributed less than 3%. The AVS concentration was very low in all but two samples from one of the shale streams, and the sum of the SEM concentrations was in molar excess of AVS for all shale stream sediments. No significant differences in mean AVS concentrations between sediments collected from shale-draining or limestone-draining sites were noted (p > 0.05). Midge survival and growth in black shale-derived sediments were significantly less (p < 0.001) than that of limestone-derived sediments. On the whole, either SEM alone or SEM-AVS explained the total variation in midge survival and growth about equally well. However, survival and growth were significantly greater (p < 0.05) in the two sediment samples that contained measurable AVS compared with the two sediments from the same stream that contained negligible AVS. ?? 2007 SETAC.

Delineation of discharge areas of two contaminant plumes by use of diffusion samplers, Johns Pond, Cape Cod, Massachusetts, 1998

USGS Publications Warehouse

Savoie, Jennifer G.; LeBlanc, D.R.; Blackwood, D.S.; McCobb, T.D.; Rendigs, R. R.; Clifford, Scott

2000-01-01

Diffusion samplers were installed in the bottom of Johns Pond, Cape Cod, Massachusetts, to confirm that volatile organic compounds from the Storm Drain-5 (SD-5) plume emanating from the Massachusetts Military Reservation (MMR) were discharging into the pond. An array of 134 vapor-diffusion samplers was buried by divers about 0.5 feet below the pond bottom in the presumed discharge area of the SD-5 plume and left in place for about 2 weeks to equilibrate. Two areas of high concentrations of volatile organic compounds (VOCs) were identified. Samples from the first area contained trichloroethene (TCE) and tetrachloroethene with concentrations in vapor as high as 890 and 667 parts per billion by volume, respectively. This discharge area is about 1,000 feet wide, extends from 100 to 350 feet offshore, and is interpreted to be the discharge area of the SD-5 plume. Samples from the second area were located closer to shore than the discharge area of the SD-5 plume and contained unexpectedly high vapor concentrations of TCE (more than 40,000 parts per billion by volume). Ground-water samples collected with a drive-point sampler near the second area had aqueous TCE concentrations as high as 1,100 micrograms per liter. Subsequently, a more closely spaced array of 110 vapor-diffusion samplers was installed to map the area of elevated TCE concentrations . The discharge area detected with the samplers is about 75 feet wide and extends from about 25 to 200 feet offshore . TCE vapor concentrations in this area were as high as 42,800 parts per billion by volume. TCE concentrations in micrograms per liter in water-diffusion samples from 15 selected sites in the two discharge areas were about 35 times lower than the TCE concentrations in parts per billion by volume in corresponding vapor-diffusion samples. The difference in values is due to the volatile nature of TCE and the different units of measure. TCE was detected in diffusion samplers set in the pond water column above the plume discharge areas, but the TCE concentrations were 20 to 30 times lower than the corresponding levels in diffusion samplers buried in the pond bottom.

Mercury concentrations and distribution in soil, water, mine waste leachates, and air in and around mercury mines in the Big Bend region, Texas, USA.

PubMed

Gray, John E; Theodorakos, Peter M; Fey, David L; Krabbenhoft, David P

2015-02-01

Samples of soil, water, mine waste leachates, soil gas, and air were collected from areas mined for mercury (Hg) and baseline sites in the Big Bend area, Texas, to evaluate potential Hg contamination in the region. Soil samples collected within 300 m of an inactive Hg mine contained elevated Hg concentrations (3.8-11 µg/g), which were considerably higher than Hg in soil collected from baseline sites (0.03-0.05 µg/g) distal (as much as 24 km) from mines. Only three soil samples collected within 300 m of the mine exceeded the probable effect concentration for Hg of 1.06 µg/g, above which harmful effects are likely to be observed in sediment-dwelling organisms. Concentrations of Hg in mine water runoff (7.9-14 ng/L) were generally higher than those found in springs and wells (0.05-3.1 ng/L), baseline streams (1.1-9.7 ng/L), and sources of drinking water (0.63-9.1 ng/L) collected in the Big Bend region. Concentrations of Hg in all water samples collected in this study were considerably below the 2,000 ng/L drinking water Hg guideline and the 770 ng/L guideline recommended by the U.S. Environmental Protection Agency (USEPA) to protect aquatic wildlife from chronic effects of Hg. Concentrations of Hg in water leachates obtained from leaching of mine wastes varied widely from <0.001 to 760 µg of Hg in leachate/g of sample leached, but only one leachate exceeded the USEPA Hg industrial soil screening level of 31 µg/g. Concentrations of Hg in soil gas collected at mined sites (690-82,000 ng/m(3)) were highly elevated compared to soil gas collected from baseline sites (1.2-77 ng/m(3)). However, air collected from mined areas at a height of 2 m above the ground surface contained concentrations of Hg (4.9-64 ng/m(3)) that were considerably lower than Hg in soil gas from the mined areas. Although concentrations of Hg emitted from mine-contaminated soils and mine wastes were elevated, persistent wind in southwest Texas disperses Hg in the air within a few meters of the ground surface.

Groundwater quality and the relation between pH values and occurrence of trace elements and radionuclides in water samples collected from private wells in part of the Kickapoo Tribe of Oklahoma Jurisdictional Area, central Oklahoma, 2011

USGS Publications Warehouse

Becker, Carol J.

2013-01-01

From 1999 to 2007, the Indian Health Service reported that gross alpha-particle activities and concentrations of uranium exceeded the Maximum Contaminant Levels for public drinking-water supplies in water samples from six private wells and two test wells in a rural residential neighborhood in the Kickapoo Tribe of Oklahoma Jurisdictional Area, in central Oklahoma. Residents in this rural area use groundwater from Quaternary-aged terrace deposits and the Permian-aged Garber-Wellington aquifer for domestic purposes. Uranium and other trace elements, specifically arsenic, chromium, and selenium, occur naturally in rocks composing the Garber-Wellington aquifer and in low concentrations in groundwater throughout its extent. Previous studies have shown that pH values above 8.0 from cation-exchange processes in the aquifer cause selected metals such as arsenic, chromium, selenium, and uranium to desorb (if present) from mineral surfaces and become mobile in water. On the basis of this information, the U.S. Geological Survey, in cooperation with the Kickapoo Tribe of Oklahoma, conducted a study in 2011 to describe the occurrence of selected trace elements and radionuclides in groundwater and to determine if pH could be used as a surrogate for laboratory analysis to quickly and inexpensively identify wells that might contain high concentrations of uranium and other trace elements. The pH and specific conductance of groundwater from 59 private wells were measured in the field in an area of about 18 square miles in Lincoln and Pottawatomie Counties. Twenty of the 59 wells also were sampled for dissolved concentrations of major ions, trace elements, gross alpha-particle and gross beta-particle activities, uranium, radium-226, radium-228, and radon-222 gas. Arsenic concentrations exceeded the Maximum Contaminant Level of 10 micrograms per liter in one sample having a concentration of 24.7 micrograms per liter. Selenium concentrations exceeded the Maximum Contaminant Level of 50 micrograms per liter in one sample having a concentration of 147 micrograms per liter. Both samples had alkaline pH values, 8.0 and 8.4, respectively. Uranium concentrations ranged from 0.02 to 383 micrograms per liter with 5 of 20 samples exceeding the Maximum Contaminant Level of 30 micrograms per liter; the five wells with uranium concentrations exceeding 30 micrograms per liter had pH values ranging from 8.0 to 8.5. Concentrations of uranium and radon-222 and gross alpha-particle activity showed a positive relation to pH, with the highest concentrations and activity in samples having pH values of 8.0 or above. The groundwater samples contained dissolved oxygen and high concentrations of bicarbonate; these characteristics are also factors in increasing uranium solubility. Concentrations of radium-226 and radium-228 (combined) ranged from 0.03 to 1.7 picocuries per liter, with a median concentration of 0.45 picocuries per liter for all samples. Radon-222 concentrations ranged from 95 to 3,600 picocuries per liter with a median concentration of 261 picocuries per liter. Eight samples having pH values ranging from 8.0 to 8.7 exceeded the proposed Maximum Contaminant Level of 300 picocuries per liter for radon-222. Eight samples exceeded the 15 picocuries per liter Maximum Contaminant Level for gross alpha-particle activity at 72 hours (after sample collection) and at 30 days (after the initial count); those samples had pH values ranging from 8.0 to 8.5. Gross beta-particle activity increased in 15 of 21 samples during the interval from 72 hours to 30 days. The increase in gross beta-particle activity over time probably was caused by the ingrowth and decay of uranium daughter products that emit beta particles. Water-quality data collected for this study indicate that pH values above 8.0 are associated with potentially high concentrations of uranium and radon-222 and high gross alpha-particle activity in the study area. High pH values also are associated with potentially high concentrations of arsenic, chromium, and selenium in groundwater when these elements occur in the aquifer matrix along groundwater-flow paths.

Aroma Leakage from Orange Juice Packed in Gable-Top Paper Containers for Chilled Distribution.

PubMed

Aoki, Risa; Tokuda, Aika; Shigemura, Yasutaka; Mineki, Machiko; Sato, Yoshio

2017-01-01

We conducted a study to examine aroma leakage from orange juice packed in gable-top paper containers for chilled distribution. Limonene, an aromatic component of orange juice, was considered as an index compound of aroma leakage, and its seepage on the surface of the container and concentration in the orange juice were measured by GC-MS for 12 commercial samples. After 3 days of storage, limonene was detected on the surface of 8 orange juice containers, and the concentration of limonene in the orange juice was found to have decreased. Thus, limonene leaked through the container within a few days, and the extent of leakage differed between containers, presumably depending upon their barrier properties. In addition, limonene was detected in green tea and milk that was stored together with the unopened orange juice containers at 4℃. The transference of orange aroma into milk was significant, because the contamination of the milk was confirmed by subjective sensory evaluation. This study suggests the possibility of transfer of aroma compounds through paper containers to other beverages.

Geochemical Characteristics of Aquifer system in Taichung Area, Central Taiwan

NASA Astrophysics Data System (ADS)

Tsai, Jui-Fen; Chen, Cheng-Hong; Liu, Tsung-Kwei

2016-04-01

For understanding the relationship between water bodies and host rocks and getting more information for groundwater in Taichung area, Central Taiwan, we systematically analyzed the stable isotopes (hydrogen and oxygen), helium isotopes and radon concentrations of dissolved gases from 54 groundwater, 39 river and 4 rain samples collected from Taichung Basin in wet and dry seasons of the year 2015. In the δ18O vs. δD plot, all samples present a linear trend similar to local meteoric water, indicating a meteoric origin. However, river samples are relative lighter than rain samples, it appears that the rivers are mainly recharged from precipitation of high-elevation areas with a lighter isotopic composition. Because the seasonal isotopic variation of river samples is significant, we calculated relative contribution of precipitation by seasons using the mass balance equation. Results show that the precipitation in the rainy season is the major source of groundwater. The helium isotopic ratio in dissolved gases of most groundwater samples are close to 1 RA (RA = 3He/4He ratio of air), except the sample from Wu-Feng well that exhibits 0.3 RA. This sample also has an older C-14 age (˜27000 yrs.) than others (<200 yrs.), implying that the dissolved helium is likely affected by radiogenic 4He of surrounding rocks. The average concentration of radon for groundwater in the northern section of Taichung Basin is 20.3 Bq/L, which is higher than that of the southern section (14.5 Bq/L). Variations of radon concentrations in the two sections may be related to the different drainage systems (Paleo-Dajia River vs. Wu River), in which sediments from Paleo-Dajia River may contain higher uranium concentrations. On the other hand, water in rivers usually contains undetectable radon (<0.37 Bq/L) because it rapidly escapes to the atmosphere. However, river samples from the central part of basin have radon concentrations ranging between 1 and 3 Bq/L, reflecting that the sampling sites are in the vicinity of points of groundwater inflow. This study illustrates the utility of hydrogen and oxygen isotopes to trace the groundwater source and determine the seasonal contribution ratios of precipitation to groundwater recharge, and demonstrates the advantage of using dissolved gas to investigate the groundwater-host rocks interaction. Key words: Central Taiwan, groundwater, dissolved gas, helium isotope, hydrogen and oxygen isotopes, water radon

100 Area Columbia River sediment sampling

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

Weiss, S.G.

1993-09-08

Forty-four sediment samples were collected from 28 locations in the Hanford Reach of the Columbia River to assess the presence of metals and man-made radionuclides in the near shore and shoreline settings of the Hanford Site. Three locations were sampled upriver of the Hanford Site plutonium production reactors. Twenty-two locations were sampled near the reactors. Three locations were sampled downstream of the reactors near the Hanford Townsite. Sediment was collected from depths of 0 to 6 in. and between 12 to 24 in. below the surface. Samples containing concentrations of metals exceeding the 95 % upper threshold limit values (DOE-RLmore » 1993b) are considered contaminated. Contamination by arsenic, chromium, copper, lead, and zinc was found. Man-made radionuclides occur in all samples except four collected opposite the Hanford Townsite. Man-made radionuclide concentrations were generally less than 1 pCi/g.« less

Personal Breathing Zone Exposures among Hot-Mix Asphalt Paving Workers; Preliminary Analysis for Trends and Analysis of Work Practices That Resulted in the Highest Exposure Concentrations

PubMed Central

Osborn, Linda V.; Snawder, John E.; Kriech, Anthony J.; Cavallari, Jennifer M.; McClean, Michael D.; Herrick, Robert F.; Blackburn, Gary R.; Olsen, Larry D.

2015-01-01

An exposure assessment of hot-mix asphalt (HMA) paving workers was conducted to determine which of four exposure scenarios impacted worker exposure and dose. Goals of this report are to present the personal-breathing zone (PBZ) data, discuss the impact of substituting the releasing/cleaning agent, and discuss work practices that resulted in the highest exposure concentration for each analyte. One-hundred-seven PBZ samples were collected from HMA paving workers on days when diesel oil was used as a releasing/cleaning agent. An additional 36 PBZ samples were collected on days when B-100 (100% biodiesel, containing no petroleum-derived products) was used as a substitute releasing/cleaning agent. Twenty-four PBZ samples were collected from a reference group of concrete workers, who also worked in outdoor construction but had no exposure to asphalt emissions. Background and field blank samples were also collected daily. Total particulates and the benzene soluble fraction were determined gravimetrically. Total organic matter was determined using gas chromatography (GC) with flame ionization detection and provided qualitative information about other exposure sources contributing to worker exposure besides asphalt emissions. Thirty-three individual polycyclic aromatic compounds (PACs) were determined using GC with time-offlight mass spectrometry; results were presented as either the concentration of an individual PAC or a summation of the individual PACs containing either 2- to 3-rings or 4- to 6-rings. Samples were also screened for PACs containing 4- to 6-rings using fluorescence spectroscopy. Arithmetic means, medians, and box plots of the PBZ data were used to evaluate trends in the data. Box plots illustrating the diesel oil results were more variable than the B-100. Also, the highest diesel oil results were much higher in concentration than the highest B-100 results. An analysis of the highest exposure results and field notes revealed a probable association between these exposures and the use of diesel oil, use of a diesel-powered screed, elevated HMA paving application temperatures, lubricating and working on broken-down equipment, and operation of a broom machine. PMID:24195533

Personal breathing zone exposures among hot-mix asphalt paving workers; preliminary analysis for trends and analysis of work practices that resulted in the highest exposure concentrations.

PubMed

Osborn, Linda V; Snawder, John E; Kriech, Anthony J; Cavallari, Jennifer M; McClean, Michael D; Herrick, Robert F; Blackburn, Gary R; Olsen, Larry D

2013-01-01

An exposure assessment of hot-mix asphalt (HMA) paving workers was conducted to determine which of four exposure scenarios impacted worker exposure and dose. Goals of this report are to present the personal-breathing zone (PBZ) data, discuss the impact of substituting the releasing/cleaning agent, and discuss work practices that resulted in the highest exposure concentration for each analyte. One-hundred-seven PBZ samples were collected from HMA paving workers on days when diesel oil was used as a releasing/cleaning agent. An additional 36 PBZ samples were collected on days when B-100 (100% biodiesel, containing no petroleum-derived products) was used as a substitute releasing/cleaning agent. Twenty-four PBZ samples were collected from a reference group of concrete workers, who also worked in outdoor construction but had no exposure to asphalt emissions. Background and field blank samples were also collected daily. Total particulates and the benzene soluble fraction were determined gravimetrically. Total organic matter was determined using gas chromatography (GC) with flame ionization detection and provided qualitative information about other exposure sources contributing to worker exposure besides asphalt emissions. Thirty-three individual polycyclic aromatic compounds (PACs) were determined using GC with time-of-flight mass spectrometry; results were presented as either the concentration of an individual PAC or a summation of the individual PACs containing either 2- to 3-rings or 4- to 6-rings. Samples were also screened for PACs containing 4- to 6-rings using fluorescence spectroscopy. Arithmetic means, medians, and box plots of the PBZ data were used to evaluate trends in the data. Box plots illustrating the diesel oil results were more variable than the B-100. Also, the highest diesel oil results were much higher in concentration than the highest B-100 results. An analysis of the highest exposure results and field notes revealed a probable association between these exposures and the use of diesel oil, use of a diesel-powered screed, elevated HMA paving application temperatures, lubricating and working on broken-down equipment, and operation of a broom machine.

Liquid-absorption preconcentrator sampling instrument

DOEpatents

Zaromb, Solomon

1990-01-01

A system for detecting trace concentrations of an analyte in air and includes a preconcentrator for the analyte and an analyte detector. The preconcentrator includes an elongated tubular container in which is disposed a wettable material extending substantially the entire length of the container. One end of the wettable material is continuously wetted with an analyte-sorbing liquid, which flows to the other end of the container. Sample air is flowed through the container in contact with the wetted material for trapping and preconcentrating the traces of analyte in the sorbing liquid, which is then collected at the other end of the container and discharged to the detector. The wetted material may be a wick comprising a bundle of fibers, one end of which is immersed in a reservoir of the analyte-sorbing liquid, or may be a liner disposed on the inner surface of the container, with the sorbing liquid being centrifugally dispersed onto the liner at one end thereof. The container is preferably vertically oriented so that gravity effects the liquid flow.

Influence of container adsorption upon observed pyrethroid toxicity to Ceriodaphnia dubia and Hyalella azteca

PubMed Central

Wheelock, Craig E.; Miller, Jeff L.; Miller, Mike J.; Phillips, Bryn M.; Gee, Shirley J.; Tjeerdema, Ronald S.; Hammock, Bruce D.

2006-01-01

Pyrethroid insecticides are known for their potential toxicity to aquatic invertebrates and many fish species. A significant problem in the study of pyrethroid toxicity is their extreme hydrophobicity. They can adsorb to test container surfaces and many studies, therefore, report pyrethroid levels as nominal water concentrations. In this study, pyrethroid adsorption to sampling and test containers was measured and several container treatments were examined for their ability to decrease pyrethroid adsorption. None of the chemical treatments were successful at preventing pyrethroid loss from aqueous samples, but vortexing of containers served to resuspend pyrethroids. The effects of the observed adsorption on Ceriodaphnia dubia and Hyalella azteca permethrin toxicity were examined. Species-specific results showed a time-dependent decrease in toxicity following pyrethroid adsorption to test containers for C. dubia, but not for H. azteca. These results demonstrate that pyrethroid adsorption to containers can significantly affect the observed outcome in toxicity-testing and serves as a caution for researchers and testing laboratories. PMID:15951033

Liquid-absorption preconcentrator sampling instrument

DOEpatents

Zaromb, S.

1990-12-11

A system is described for detecting trace concentrations of an analyte in air and includes a preconcentrator for the analyte and an analyte detector. The preconcentrator includes an elongated tubular container in which is disposed a wettable material extending substantially the entire length of the container. One end of the wettable material is continuously wetted with an analyte-sorbing liquid, which flows to the other end of the container. Sample air is flowed through the container in contact with the wetted material for trapping and preconcentrating the traces of analyte in the sorbing liquid, which is then collected at the other end of the container and discharged to the detector. The wetted material may be a wick comprising a bundle of fibers, one end of which is immersed in a reservoir of the analyte-sorbing liquid, or may be a liner disposed on the inner surface of the container, with the sorbing liquid being centrifugally dispersed onto the liner at one end thereof. The container is preferably vertically oriented so that gravity effects the liquid flow. 4 figs.

Hydrogeology and water quality of five principal aquifers in the Lower Platte South Natural Resources District, eastern Nebraska, 1994

USGS Publications Warehouse

Druliner, A.D.; Mason, J.P.

2001-01-01

The U.S. Geological Survey, in cooperation with the Lower Platte South Natural Resources District, conducted a hydrogeologic and water-quality reconnaissance study of the five principal aquifers in deposits of Quaternary age in the Natural Resources District. The purpose of the study was to delineate the approximate extent of the aquifers, to estimate volumes of drainable water in three aquifers, to provide information that could be useful in designing future ground-water-quality monitoring, and to determine baseline water-quality conditions in the aquifers, focusing on nitrate concentrations. The approximate lateral boundaries of the Dwight-Valparaiso, Crete-Princeton-Adams, and Waverly aquifers were defined as areas in which the thickness of continuous sand and gravel deposits was less than 40 feet. The three aquifers were determined to contain about 1,340,000; 1,540,000; and 172,000 acre-feet of drainable water, respectively, assuming a specific yield of 0.20. During the summer of 1994, ground-water samples were collected from 46 wells in the five aquifers and analyzed for nitrate and screened for triazine herbicides. Additionally, water samples from 39 of these wells were analyzed for major ions, iron, and manganese, and 35 were analyzed for radon. Water-quality analyses revealed that the water in the five aquifers had specific conductances that ranged from 399 to 2,040 micro-siemens per centimeter and was a calcium-carbonate to calcium-magnesium-sodium carbonate type. The most mineralized water samples were from the Crete-Princeton-Adams aquifer, which contained a median concentration of dissolved solids of 520 milligrams per liter. Concentrations of nitrate in water samples from the aquifers ranged from less than 0.05 to 23 milligrams per liter as nitrogen, and only six water samples exceeded the Maximum Contaminant Level established by the U.S. Environmental Protection Agency of 10 milligrams per liter. The median concentration of radon for water samples from the five aquifers was 300 picocuries per liter, which is the proposed Maximum Contaminant Level. Water samples from the Crete-Princeton-Adams and Waverly aquifers had the largest concentrations of radon among the five aquifers. The Crete-Princeton-Adams aquifer had a median concentration of 440 picocuries per liter, and the Waverly aquifer had a median concentration of 390 picocuries per liter. Herbicides were detected in water from only six wells, which were in four of the five aquifers. Atrazine, metabolites of atrazine, metolachlor, and metribuzin were detected in concentrations generally less than 1.00 microgram per liter.

Iodine-129 in the eastern Snake River Plain aquifer at and near the Idaho National Laboratory, Idaho, 2010-12

USGS Publications Warehouse

Bartholomay, Roy C.

2013-01-01

From 1953 to 1988, approximately 0.941 curies of iodine-129 (129I) were contained in wastewater generated at the Idaho National Laboratory (INL) with almost all of this wastewater discharged at or near the Idaho Nuclear Technology and Engineering Center (INTEC). Most of the wastewater containing 129I was discharged directly into the eastern Snake River Plain (ESRP) aquifer through a deep disposal well until 1984; lesser quantities also were discharged into unlined infiltration ponds or leaked from distribution systems below the INTEC. During 2010–12, the U.S. Geological Survey in cooperation with the U.S. Department of Energy collected groundwater samples for 129I from 62 wells in the ESRP aquifer to track concentration trends and changes for the carcinogenic radionuclide that has a 15.7 million-year half-life. Concentrations of 129I in the aquifer ranged from 0.0000013±0.0000005 to 1.02±0.04 picocuries per liter (pCi/L), and generally decreased in wells near the INTEC, relative to previous sampling events. The average concentration of 129I in groundwater from 15 wells sampled during four different sample periods decreased from 1.15 pCi/L in 1990–91 to 0.173 pCi/L in 2011–12. All but two wells within a 3-mile radius of the INTEC showed decreases in concentration, and all but one sample had concentrations less than the U.S. Environmental Protection Agency maximum contaminant level of 1 pCi/L. These decreases are attributed to the discontinuation of disposal of 129I in wastewater and to dilution and dispersion in the aquifer. The decreases in 129I concentrations, in areas around INTEC where concentrations increased between 2003 and 2007, were attributed to less recharge near INTEC either from less flow in the Big Lost River or from less local snowmelt and anthropogenic sources. Although wells near INTEC sampled in 2011–12 showed decreases in 129I concentrations compared with previously collected data, some wells south and east of the Central Facilities Area, near the site boundary, and south of the INL showed small increases. These slight increases are attributed to variable discharge rates of wastewater that eventually moved to these well locations as a pulse of water from a particular disposal period. Wells sampled for the first time around the Naval Reactors Facility had 129I concentrations slightly greater than background concentrations in the ESRP aquifer. These concentrations are attributed to possible leakage from landfills at the Naval Reactors Facility or seepage from air emission deposits from INTEC, or both. In 2012, the U.S. Geological Survey collected discrete groundwater samples from 25 zones in 11 wells equipped with multilevel monitoring systems to help define the vertical distribution of 129I in the aquifer. Concentrations ranged from 0.000006±0.000004 to 0.082±0.003 pCi/L. Two new wells completed in 2012 showed variability of up to one order of magnitude of concentrations of 129I among various zones. Two other wells showed similar concentrations of 129I in all three zones sampled. Concentrations were well less than the maximum contaminant level in all zones.

Accurate mass replacement method for the sediment concentration measurement with a constant volume container

NASA Astrophysics Data System (ADS)

Ban, Yunyun; Chen, Tianqin; Yan, Jun; Lei, Tingwu

2017-04-01

The measurement of sediment concentration in water is of great importance in soil erosion research and soil and water loss monitoring systems. The traditional weighing method has long been the foundation of all the other measuring methods and instrument calibration. The development of a new method to replace the traditional oven-drying method is of interest in research and practice for the quick and efficient measurement of sediment concentration, especially field measurements. A new method is advanced in this study for accurately measuring the sediment concentration based on the accurate measurement of the mass of the sediment-water mixture in the confined constant volume container (CVC). A sediment-laden water sample is put into the CVC to determine its mass before the CVC is filled with water and weighed again for the total mass of the water and sediments in the container. The known volume of the CVC, the mass of sediment-laden water, and sediment particle density are used to calculate the mass of water, which is replaced by sediments, therefore sediment concentration of the sample is calculated. The influence of water temperature was corrected by measuring water density to determine the temperature of water before measurements were conducted. The CVC was used to eliminate the surface tension effect so as to obtain the accurate volume of water and sediment mixture. Experimental results showed that the method was capable of measuring the sediment concentration from 0.5 up to 1200 kg m-3. A good liner relationship existed between the designed and measured sediment concentrations with all the coefficients of determination greater than 0.999 and the averaged relative error less than 0.2%. All of these seem to indicate that the new method is capable of measuring a full range of sediment concentration above 0.5 kg m-3 to replace the traditional oven-drying method as a standard method for evaluating and calibrating other methods.

In vitro antibacterial and cytotoxicity assessments of an orthodontic bonding agent containing benzalkonium chloride.

PubMed

Saito, Kayo; Hayakawa, Tohru; Kawabata, Rihito; Meguro, Daijiro; Kasai, Kazutaka

2009-03-01

To assess the antibacterial activity and cytotoxicity of an orthodontic bonding material containing an antibacterial agent. Superbond C&B (4-methacryloxyethyl trimellitate anhydride/methyl methacrylate-tri-n-butyl borane [4-META/MMA-TBB]) resin was mixed with benzalkonium chloride (BAC) to obtain final BAC concentrations of 0.25%, 0.75%, 1.25%, 1.75%, 2.5%, and 5.0% (wt/ wt). Antibacterial activity against Streptococcus mutans and Streptococcus sobrinus was evaluated by soaking the BAC-resin in distilled water at 37 degrees C for periods of 30, 90, and 180 days. Antibacterial activity of the BAC-resin was measured by the disk diffusion method, and the inhibition zone around each sample was measured and recorded. For evaluation of cytotoxicity, BAC-resin samples were put into cell culture inserts placed above human gingival cells and were incubated at 37 degrees C for 1, 3, and 6 days. Cytotoxicity was assessed with a tetrazolium bromide reduction assay. The antibacterial activity of BAC-incorporated resin samples decreased significantly after immersion in water for 180 days, regardless of BAC concentration. The antibacterial activity of nonimmersed resin containing 0.25% or 1.75% BAC was comparable with that of 5.0% BAC-resin immersed for 180 days. In cytotoxicity tests, most cells died when exposed to resins containing 1.75%, 2.5%, and 5% BAC. No difference was observed between resins containing 0.25% and 0.75% BAC at 1, 3, and 6 days of culture. The addition of BAC to 4-META/MMA-TBB resin confers an antibacterial effect even after immersion in water, and 4-META/MMA-TBB resin containing 0.25% to 0.75% BAC has no significant cytotoxic effect.

Quality of water in the fractured-bedrock aquifer of New Hampshire

USGS Publications Warehouse

Moore, Richard Bridge

2004-01-01

Over the past few decades, New Hampshire has experienced considerable population growth, which is forcing some communities to look for alternative public and private water supplies in the bedrock aquifer. Because the quality of water from the aquifer can vary, the U.S. Geological Survey statistically analyzed well data from 1,353 domestic and 360 public-supply bedrock wells to characterize the ground water. The domestic-well data were from homeowner-collected samples analyzed by the New Hampshire Department of Environmental Services (NHDES) Environmental Laboratory from 1984 to 1994. Bedrock water in New Hampshire often contains high concentrations of iron, manganese, arsenic, and radon gas. Water samples from 21 percent of the domestic bedrock wells contained arsenic above the U.S. Environmental Protection Agency (USEPA) 10 micrograms per liter (?g/L) drinking-water standard for public-water supplies, and 96 percent had radon concentrations greater than the USEPA-proposed 300 picocurie per liter (pCi/L) standard for public-water supplies. Some elevated fluoride concentrations (2 percent of samples) were above the 4 milligrams per liter (mg/L) USEPA drinking-water standard for public-water supplies. Water from the bedrock aquifer also typically is soft to moderately hard, and has a pH greater than 7.0. Variations in bedrock water quality were discernable when the data were compared to lithochemical groupings of the bedrock, indicating that the type of bedrock has an effect on the quality of water in the bedrock aquifer of New Hampshire. Ground-water samples from the metasedimentary lithochemical group have greater concentrations of total iron and total manganese than do the felsic and mafic igneous lithochemical groups. Ground-water samples from the felsic igneous group have higher concentrations of total fluoride than do those from the other lithochemical groups. For arsenic, the calcareous metasedimentary group was identified, using the public-supply database, as having higher concentrations, on average, than the other lithochemical groups. The use of a radon-gas-potential classification of bedrock in the State indicated where high radon concentrations in the air and in water from private and public-supply wells were more likely to occur. In general, samples from the bedrock aquifer tend to have higher pH (are less acidic), greater hardness, much higher concentrations of iron, similar concentrations of manganese, and higher concentrations of fluoride and arsenic than do samples from stratified-drift aquifers in New Hampshire. An understanding of the water-quality conditions of water in bedrock aquifers is important from a public-health perspective because an increasing number of domestic bedrock wells are being drilled and relied upon as a source of drinking water in the State.

Gasoline-related organics in Lake Tahoe before and after prohibition of carbureted two-stroke engines

USGS Publications Warehouse

Lico, M.S.

2004-01-01

On June 1, 1999, carbureted two-stroke engines were banned on waters within the Lake Tahoe Basin of California and Nevada. The main gasoline components MTBE (methyl tert-butyl ether) and BTEX (benzene, toluene, ethylbenzene, and xylenes) were present at detectable concentrations in all samples taken from Lake Tahoe during 1997-98 prior to the ban. Samples taken from 1999 through 2001 after the ban contained between 10 and 60 percent of the pre-ban concentrations of these compounds, with MTBE exhibiting the most dramatic change (a 90 percent decrease). MTBE and BTEX concentrations in water samples from Lake Tahoe and Lower Echo Lake were related to the amount of boat use at the sampling sites. Polycyclic aromatic hydrocarbon (PAH) compounds are produced by high-temperature pyrolytic reactions. They were sampled using semipermeable membrane sampling devices in Lake Tahoe and nearby Donner Lake, where carbureted two-stroke engines are legal. PAHs were detected in all samples taken from Lake Tahoe and Donner Lake. The number of PAH compounds and their concentrations are related to boat use. The highest concentrations of PAH were detected in samples from two heavily used boating areas, Tahoe Keys Marina and Donner Lake boat ramp. Other sources of PAH, such as atmospheric deposition, wood smoke, tributary streams, and automobile exhaust do not contribute large amounts of PAH to Lake Tahoe. Similar numbers of PAH compounds and concentrations were found in Lake Tahoe before and after the ban of carbureted two-stroke engines. ?? by the North American Lake Management Society 2004.

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

Broxton, D.E.

A total of 338 water and 1877 sediment samples were collected over a 20,700-km/sup 2/ area from 2125 locations at a nominal density of one sample per 10 km/sup 2/. Water samples were collected from wells, streams, springs, and artificial ponds. Sediment samples were collected from streams, springs, natural ponds, and artificial ponds. Arbitrary anomaly thresholds of two standard deviations above the mean were chosen for both water and sediment sample populations. The U concentrations in waters collected in the Tularosa quadrangle range from below the detection limit of 0.2 parts per billion (ppB) to 57.8 ppB. Most clusters ofmore » water samples containing anomalously high uranium concentrations were collected from locations in uplifts underlain either by volcanic rocks of the mid-Tertiary Datil group or by sedimentary rocks of late Paleozoic and Mesozoic age. Other groups of anomalous waters are from wells that tap Cenozoic aquifers in the intermontane basins. In those areas where the water-sample location coverage is adequate, the known U occurrences are generally associated with high or anomalous U concentrations in water samples. With the exception of one sample with a U concentration of 67.7 ppM, sediments collected in this study have U concentrations that range between 0.2 and 15.2 ppM. Most sediments with U concentrations above the arbitrary anomaly threshold value are from locations which occur in or parallel outcrops of Precambrian crystalline rock exposed in the San Andres and Oscura Mountains. Other anomalous sediments occur as more discreet groups in areas underlain by mid-Tertiary volcanic rocks of the Datil group. Several anomalous samples from the Mogollon-Datil volcanic field were collected along ring fracture systems that surround large volcanic cauldrons.« less

Occurrence of microbial indicators and Clostridium perfringens in wastewater, water column samples, sediments, drinking water, and Weddell seal feces collected at McMurdo Station, Antarctica

USGS Publications Warehouse

Lisle, J.T.; Smith, J.J.; Edwards, D.D.; McFeters, G.A.

2004-01-01

McMurdo Station, Antarctica, has discharged untreated sewage into McMurdo Sound for decades. Previous studies delineated the impacted area, which included the drinking water intake, by using total coliform and Clostridium perfringens concentrations. The estimation of risk to humans in contact with the impacted and potable waters may be greater than presumed, as these microbial indicators may not be the most appropriate for this environment. To address these concerns, concentrations of these and additional indicators (fecal coliforms, Escherichia coli, enterococci, coliphage, and enteroviruses) in the untreated wastewater, water column, and sediments of the impacted area and drinking water treatment facility and distribution system at McMurdo Station were determined. Fecal samples from Weddell seals in this area were also collected and analyzed for indicators. All drinking water samples were negative for indicators except for a single total coliform-positive sample. Total coliforms were present in water column samples at higher concentrations than other indicators. Fecal coliform and enterococcus concentrations were similar to each other and greater than those of other indicators in sediment samples closer to the discharge site. C. perfringens concentrations were higher in sediments at greater distances from the discharge site. Seal fecal samples contained concentrations of fecal coliforms, E. coli, enterococci, and C. perfringens similar to those found in untreated sewage. All samples were negative for enteroviruses. A wastewater treatment facility at McMurdo Station has started operation, and these data provide a baseline data set for monitoring the recovery of the impacted area. The contribution of seal feces to indicator concentrations in this area should be considered.

Anthropogenic Organic Compounds in Ground Water and Finished Water of Community Water Systems near Dayton, Ohio, 2002-04

USGS Publications Warehouse

Thomas, Mary Ann

2007-01-01

Source water for 15 community-water-system (CWS) wells in the vicinity of Dayton, Ohio, was sampled to evaluate the occurrence of 258 anthropogenic compounds (AOCs). At least one AOC was detected in 12 of the 15 samples. Most samples contained a mixture of compounds (average of four compounds per sample). The compounds that were detected in more than 30 percent of the samples included three volatile organic compounds (VOCs) (trichloroethene, chloroform, and 1,1,1-trichloroethane) and four pesticides or pesticide breakdown products (prometon, simazine, atrazine, and deethylatrazine). In general, VOCs were detected at higher concentrations than pesticides were; among the VOCs, the maximum detected concentration was 4.8 ?g/L (for trichloroethene), whereas among the pesticides, the maximum detected concentration was 0.041 ?g/L (for atrazine). During a later phase of the study, samples of source water from five CWS wells were compared to samples of finished water associated with each well. In general, VOC detections were higher in finished water than in source water, primarily due to the occurrence of trihalomethanes, which are compounds that can form during the treatment process. In contrast, pesticide detections were relatively similar between source- and finished-water samples. To assess the human-health relevance of the data, concentrations of AOCs were compared to their respective human-health benchmarks. For pesticides, the maximum detected concentrations were at least 2 orders of magnitude less than the benchmark values. However, three VOCs - trichloroethene, carbon tetrachloride, and tetrachloromethane - were detected at concentrations that approach human-health benchmarks and therefore may warrant inclusion in a low-concentration, trends monitoring program.

Chlorinated hydrocarbons in livers of American mink (Mustela vison) and river otter (Lutra canadensis) from the Columbia and Fraser River Basins, 1990-1992

USGS Publications Warehouse

Elliott, J.E.; Henny, Charles J.; Harris, M.L.; Wilson, L.K.; Norstrom, R.J.

1999-01-01

We investigated chlorinated hydrocarbon contaminants in aquatic mustelid species on the Fraser and Columbia Rivers of northwestern North America. Carcasses of river otter (Lutra canadensis) (N=24) and mink (Mustela vison) (N=34) were obtained from commercial trappers during the winters of 1990-91 and 1991a??92. Pooled liver samples were analyzed for organochlorine pesticides, polychlorinated biphenyls (PCBs), including non-ortho congeners, polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs). Most samples contained detectable concentrations of DDE, PCBs, although there was substantial variability in patterns and trends among neighboring samples. Concentrations of DDE were in some mink and several otter samples from the lower Columbia River elevated (to 4700 g/kg wet weight); excluding one mink sample from the Wenatchee area, mean DDE levels generally decreased between 1978a??79 and 1990a??92. PCBs were present in all samples. PCB concentrations in otter livers collected from the lower Columbia were ten-fold lower than measured a decade previously; nevertheless, a sample taken near Portland had a mean concentration of 1500 g/kg, within a range of concentrations associated with reproductive effects in captive mink. Concentrations of 2,3,7,8-TCDD and TCDF were generally below detection limits, except for one otter collected near a pulp mill at Castlegar, on the upper Columbia, with 11 ng TCDD/kg in liver. Elevated concentrations of higher chlorinated PCDD/Fs, probably resulting from use of chlorophenolic wood preservatives, were found in both species; one otter sample from the lower Columbia had 2200 ng OCDD/kg. International TCDD toxic equivalent levels in mink (31 ng/kg) and otter (93 ng/kg) from the lower Columbia River approached toxicity thresholds for effects on reproduction in ranch mink.

Automated agar plate streaker: a linear plater on Society for Biomolecular Sciences standard plates.

PubMed

King, Gregory W; Kath, Gary S; Siciliano, Sal; Simpson, Neal; Masurekar, Prakash; Sigmund, Jan; Polishook, Jon; Skwish, Stephen; Bills, Gerald; Genilloud, Olga; Peláez, Fernando; Martín, Jesus; Dufresne, Claude

2006-09-01

Several protocols for bacterial isolation and techniques for aerobic plate counting rely on the use of a spiral plater to deposit concentration gradients of microbial suspensions onto a circular agar plate to isolate colony growth. The advantage of applying a gradient of concentrations across the agar surface is that the original microbiological sample can be applied at a single concentration rather than as multiple serial dilutions. The spiral plater gradually dilutes the sample across a compact area and therefore saves time preparing dilutions and multiple agar plates. Commercial spiral platers are not automated and require manual sample loading. Dispensing of the sample volume and rate of gradients are often very limited in range. Furthermore, the spiral sample application cannot be used with rectangular microplates. Another limitation of commercial spiral platers is that they are useful only for dilute, filtered suspensions and cannot plate suspensions of coarse organic particles therefore precluding the use of many kinds of microorganism-containing substrata. An automated agar plate spreader capable of processing 99 rectangular microplates in unattended mode is described. This novel instrument is capable of dispensing discrete volumes of sample in a linear pattern. It can be programmed to dispense a sample suspense at a uniform application rate or across a decreasing concentration gradient.

Residues of 2, 4-D in air samples from Saskatchewan: 1966-1975.

PubMed

Grover, R; Kerr, L A; Wallace, K; Yoshida, K; Maybank, J

1976-01-01

Residues of 2,4-D (2,4-dichlorophenoxyacetic acid) in air samples from several sampling sites in central and southern Saskatchewan during the spraying seasons in the 1966-68 and 1970-75 periods were determined by gas-liquid chromatographic techniques. Initially, individual esters of 2,4-D were characterized by retention times and confirmed further by co-injection and dual column procedures. Since 1973, however, only total 2,4-D acid levels in air samples have been determined after esterification to the methyl ester and confirmed by gc/ms techniques whenever possible. Up to 50% of the daily samples collected during the spraying season at any of the locations and during any given year contained 2,4-D, with butyl esters being found most frequently. The daily 24-hr mean atmospheric concentrations of 2,4-D ranged from 0.01 to 1.22 mug/m3, 0.01 to 13.50 mug/m3, and 0.05 to 0.59 mug/m3 for the iso-propyl, mixed butyl and iso-octyl esters, respectively. Even when the samples were analysed for the total 2,4-D content, i.e. from 1973 onwards, the maximum level of the total acid reached only 23.14 mug/m3. In any given year and at any of the sampling sites, about 30% of the samples contained less than 0.01 mug/m3 of 2,4-D. In another 40% of the samples, the levels of 2,4-D ranged from 0.01 to 0.099 mug/m3. Only about 30% of the samples contained 2,4-D concentrations higher than 0.1 mug/m3, with only 10% or less exceeding 1 mug/m3. None of the samples, obtained with the high volume particulate sampler, showed any detectable levels of 2,4-D, indicating little or no transport of 2,4-D adsorbed on dust particles or as crystals of amine salts.

Alaska Geochemical Database - Mineral Exploration Tool for the 21st Century - PDF of presentation

USGS Publications Warehouse

Granitto, Matthew; Schmidt, Jeanine M.; Labay, Keith A.; Shew, Nora B.; Gamble, Bruce M.

2012-01-01

The U.S. Geological Survey has created a geochemical database of geologic material samples collected in Alaska. This database is readily accessible to anyone with access to the Internet. Designed as a tool for mineral or environmental assessment, land management, or mineral exploration, the initial version of the Alaska Geochemical Database - U.S. Geological Survey Data Series 637 - contains geochemical, geologic, and geospatial data for 264,158 samples collected from 1962-2009: 108,909 rock samples; 92,701 sediment samples; 48,209 heavy-mineral-concentrate samples; 6,869 soil samples; and 7,470 mineral samples. In addition, the Alaska Geochemical Database contains mineralogic data for 18,138 nonmagnetic-fraction heavy mineral concentrates, making it the first U.S. Geological Survey database of this scope that contains both geochemical and mineralogic data. Examples from the Alaska Range will illustrate potential uses of the Alaska Geochemical Database in mineral exploration. Data from the Alaska Geochemical Database have been extensively checked for accuracy of sample media description, sample site location, and analytical method using U.S. Geological Survey sample-submittal archives and U.S. Geological Survey publications (plus field notebooks and sample site compilation base maps from the Alaska Technical Data Unit in Anchorage, Alaska). The database is also the repository for nearly all previously released U.S. Geological Survey Alaska geochemical datasets. Although the Alaska Geochemical Database is a fully relational database in Microsoft® Access 2003 and 2010 formats, these same data are also provided as a series of spreadsheet files in Microsoft® Excel 2003 and 2010 formats, and as ASCII text files. A DVD version of the Alaska Geochemical Database was released in October 2011, as U.S. Geological Survey Data Series 637, and data downloads are available at http://pubs.usgs.gov/ds/637/. Also, all Alaska Geochemical Database data have been incorporated into the interactive U.S. Geological Survey Mineral Resource Data web portal, available at http://mrdata.usgs.gov/.

Evaluation of Optimum Dietary Threonine Requirement by Plasma Free Threonine and Ammonia Concentrations in Surgically Modified Rainbow Trout, Oncorhynchus mykiss

PubMed Central

Yun, Hyeonho; Park, Gunjun; Ok, Imho; Katya, Kumar; Heung, Silas; Bai, Sungchul C.

2015-01-01

This study was carried out to evaluate the dietary threonine requirement by measuring the plasma free threonine and ammonia concentrations in rainbow trout, Oncorhynchus mykiss after dorsal aorta cannulation. A total of 70 fish (average initial weight 506±8.2 g) were randomly distributed into each of the 14 net cages (5 fish/cage). After 48 hours (h) of feed deprivation, each group was intubated at 1% body weight with one of the seven L-amino acid based diets containing graded levels of threonine (0.42%, 0.72%, 0.92%, 1.12%, 1.32%, 1.52%, or 1.82% of diet, dry matter basis). Blood samples were taken at 0, 5, and 24 h after intubation. Post-prandial plasma free threonine concentrations (PPthr) of fish 5 h after intubation with diets containing 1.32% or more threonine were significantly higher than those of fish intubated with diets containing 1.12% or less threonine (p<0.05). Post-absorptive free threonine concentrations (PAthr) after 24 h of intubation of the fish with diets containing 0.92% or more threonine were significantly higher than those of fish intubated with diets containing 0.72% or less threonine. Post-prandial plasma ammonia concentrations (PPA, 5 h after intubation) were not significantly different among fish intubated with diets containing 1.12% or less threonine, except the PPA of fish intubated with diet containing 0.42% threonine. Broken-line model analyses of PPthr, PAthr, and PPA indicated that the dietary threonine requirement of rainbow trout should be between 0.95% (2.71) and 1.07% (3.06) of diet (% of dietary protein on a dry matter basis). PMID:25656187

Okara promoted acrylamide and carboxymethyl-lysine formation in bakery products.

PubMed

Palermo, Mariantonella; Fiore, Alberto; Fogliano, Vincenzo

2012-10-10

Soybeans are widely used in bakery products because of their technological advantages and, recently, soybean-containing products have been marketed as functional foods thanks to several health benefits. Okara is a soybean-based ingredient obtained after elimination of the water-soluble component from ground soybeans. In this paper the effect of okara addition to bakery products on the formation of some potentially harmful Maillard reaction products was evaluated. Cookies obtained by replacing 15% of wheat flour with okara showed a visible browning increase and a more intense Maillard reaction development as shown by higher concentrations of 5-hydroxymethyl-2-furaldehyde (HMF) (+100%), acrylamide (+60%), and carboxymethyl-lysine (CML) (+400%) with respect to the control. This phenomenon could be related to the presence in okara of about 50% of insoluble dietary fiber: the fiber reduces water activity during cooking, thus promoting Maillard reaction. To confirm this hypothesis, cookies obtained by replacing 7% of wheat flour with three different types of dietary fiber (cellulose, chitosan, and pea fiber) were prepared: these experimental cookies showed higher Maillard reaction product concentration with respect to the control and, in particular, HMF and CML values were directly related to the fiber water-holding capacity (WHC). To extend the observation to the food market, a sampling of soybean-containing commercial bakery products was analyzed by comparing the concentrations of Maillard reaction products with those of similar bakery products without soy. Soybean-containing samples showed higher concentrations of acrylamide and CML than corresponding controls.

Inhibition of Sodium Benzoate on Stainless Steel in Tropical Seawater

NASA Astrophysics Data System (ADS)

Seoh, S. Y.; Senin, H. B.; Nik, W. N. Wan; Amin, M. M.

2007-05-01

The inhibition of sodium benzoate for stainless steel controlling corrosion was studied in seawater at room temperature. Three sets of sample have been immersed in seawater containing sodium benzoate with the concentrations of 0.3M, 0.6M and 1.0M respectively. One set of sample has been immersed in seawater without adding any sodium benzoate. It was found that the highest corrosion rate was observed for the stainless steel with no inhibitor was added to the seawater. As the concentration of sodium benzoate being increased, the corrosion rate is decreases. Results show that by the addition of 1.0M of sodium benzoate in seawater samples, it giving ≥ 90% efficiencies.

Manifold and method of batch measurement of Hg-196 concentration using a mass spectrometer

DOEpatents

Grossman, Mark W.; Evans, Roger

1991-01-01

A sample manifold and method of its use has been developed so that milligram quantities of mercury can be analyzed mass spectroscopically to determine the .sup.196 Hg concentration to less than 0.02 atomic percent. Using natural mercury as a standard, accuracy of .+-.0.002 atomic percent can be obtained. The mass spectrometer preferably used is a commercially available GC/MS manufactured by Hewlett Packard. A novel sample manifold is contained within an oven allowing flow rate control of Hg into the MS. Another part of the manifold connects to an auxiliary pumping system which facilitates rapid clean up of residual Hg in the manifold. Sample cycle time is about 1 hour.

Environmental geochemistry of abandoned mercury mines in West-Central Nevada, USA

USGS Publications Warehouse

Gray, J.E.; Crock, J.G.; Fey, D.L.

2002-01-01

The Humboldt River is a closed basin and is the longest river in Nevada. Numerous abandoned Hg mines are located within the basin, and because Hg is a toxic heavy metal, the potential transport of Hg from these mines into surrounding ecosystems, including the Humboldt River, is of environmental concern Samples of ore, sediment, water, calcines (roasted ore), and leachates of the calcines were analyzed for Hg and other heavy metals to evaluate geochemical dispersion from the mines. Cinnabar-bearing ore samples collected from the mines contain highly elevated Hg concentrations, up to 6.9 %, whereas calcines collected from the mines contain up to 2000 mg Hg/kg. Stream-sediment samples collected within 1 km of the mines contain as much as 170 mg Hg/kg, but those collected distal from the mines (> 5 km) contain 8 km from the Humboldt River, and Hg is transported and diluted through a large volume of pediment before it reaches the Humboldt River. ?? 2002 Elsevier Science Ltd. All rights reserved.

Innovations in Sampling Pore Fluids From Deep-Sea Hydrate Sites

NASA Astrophysics Data System (ADS)

Lapham, L. L.; Chanton, J. P.; Martens, C. S.; Schaefer, H.; Chapman, N. R.; Pohlman, J. W.

2003-12-01

We have developed a sea-floor probe capable of collecting and returning undecompressed pore water samples at in situ pressures for determination of dissolved gas concentrations and isotopic values in deep-sea sediments. In the summer of 2003, we tested this instrument in sediments containing gas hydrates off Vancouver Island, Cascadia Margin from ROPOS (a remotely operated vehicle) and in the Gulf of Mexico from Johnson-Sea-Link I (a manned submersible). Sediment push cores were collected alongside the probe to compare methane concentrations and stable carbon isotope compositions in decompressed samples vs. in situ samples obtained by probe. When sufficient gas was available, ethane and propane concentrations and isotopes were also compared. Preliminary data show maximum concentrations of dissolved methane to be 5mM at the Cascadia Margin Fish Boat site (850m water depth) and 12mM in the Gulf of Mexico Bush Hill hydrate site (550m water depth). Methane concentrations were, on average, five times as high in probe samples as in the cores. Carbon isotopic values show a thermogenic input and oxidative effects approaching the sediment-water interface at both sites. This novel data set will provide information that is critical to the understanding of the in situ processes and environmental conditions controlling gas hydrate occurrences in sediments.

Maps showing mineralogical data for nonmagnetic heavy-mineral concentrates in the Talkeetna Quadrangle, Alaska

USGS Publications Warehouse

Tripp, R.B.; Karlson, R.C.; Curtin, G.C.

1978-01-01

Reconnaissance geochemical and mineralogical sampling was done in the Talkeetna Quadrangle during 1975 and 1976 as part of the Alaska Mineral Resource Assessment Program (AMRAP). These maps show the distribution of gold, scheelite, chalcopyrite, arsenopyrite, galena, fluorite, cinnabar, and malachite in the nonmagnetic fraction of heavy-mineral concentrates. Heavy-mineral concentrate samples were collected at 812 sites from active stream channels. The heavy-mineral concentrates were obtained by panning stream sediment in the field to remove most of the light minerals. The panned samples were then sieved through a 20-mesh (0.8 mm) sieve in the laboratory, and the minus-20-mesh fraction was further separated with bromoform (specific gravity, 2.86) to remove any remaining light-mineral grains. Magnetite and other strongly magnetic heavy minerals were removed from the heavy-mineral fraction by use of a hand magnet. The remaining sample was passed through a Frantz Isodynamic Separator and a nonmagnetic fraction was examined for its mineralogical content with the aid of a binocular microscope and an x-ray diffractometer. The nonmagnetic concentrates primarily contain phyllite fragments, muscovite, sphene, zircon, apatite, tourmaline, rutile, and anatase. Most ore and ore-related minerals also occur in this fraction.

Quality assurance in RT-PCR-based BCR/ABL diagnostics--results of an interlaboratory test and a standardization approach.

PubMed

Burmeister, T; Maurer, J; Aivado, M; Elmaagacli, A H; Grünebach, F; Held, K R; Hess, G; Hochhaus, A; Höppner, W; Lentes, K U; Lübbert, M; Schäfer, K L; Schafhausen, P; Schmidt, C A; Schüler, F; Seeger, K; Seelig, R; Thiede, C; Viehmann, S; Weber, C; Wilhelm, S; Christmann, A; Clement, J H; Ebener, U; Enczmann, J; Leo, R; Schleuning, M; Schoch, R; Thiel, E

2000-10-01

Here we describe the results of an interlaboratory test for RT-PCR-based BCR/ABL analysis. The test was organized in two parts. The number of participating laboratories in the first and second part was 27 and 20, respectively. In the first part samples containing various concentrations of plasmids with the ela2, b2a2 or b3a2 BCR/ABL transcripts were analyzed by PCR. In the second part of the test, cell samples containing various concentrations of BCR/ABL-positive cells were analyzed by RT-PCR. Overall PCR sensitivity was sufficient in approximately 90% of the tests, but a significant number of false positive results were obtained. There were significant differences in sensitivity in the cell-based analysis between the various participants. The results are discussed, and proposals are made regarding the choice of primers, controls, conditions for RNA extraction and reverse transcription.

Preliminary evaluation of optical glucose sensing in red cell concentrations using near-infrared diffuse-reflectance spectroscopy

NASA Astrophysics Data System (ADS)

Suzuki, Yusuke; Maruo, Katsuhiko; Zhang, Alice W.; Shimogaki, Kazushige; Ogawa, Hideto; Hirayama, Fumiya

2012-01-01

Bacterial contamination of blood products is one of the most frequent infectious complications of transfusion. Since glucose levels in blood supplies decrease as bacteria proliferate, it should be possible to detect the presence of bacterial contamination by measuring the glucose concentrations in the blood components. Hence this study is aimed to serve as a preliminary study for the nondestructive measurement of glucose level in transfusion blood. The glucose concentrations in red blood cell (RBC) samples were predicted using near-infrared diffuse-reflectance spectroscopy in the 1350 to 1850 nm wavelength region. Furthermore, the effects of donor, hematocrit level, and temperature variations among the RBC samples were observed. Results showed that the prediction performance of a dataset which contained samples that differed in all three parameters had a standard error of 29.3 mg/dL. Multiplicative scatter correction (MSC) preprocessing method was also found to be effective in minimizing the variations in scattering patterns created by various sample properties. The results suggest that the diffuse-reflectance spectroscopy may provide another avenue for the detection of bacterial contamination in red cell concentrations (RCC) products.

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.

Proton Induced X-Ray Emission (PIXE): Determining the Concentration of Samples

NASA Astrophysics Data System (ADS)

McCarthy, Mallory; Rodriguez Manso, Alis; Pajouhafsar, Yasmin; J Yennello, Sherry

2017-09-01

We used Proton Induced X-ray Emission (PIXE) as an analysis technique to determine the composition of samples, in particular, the elemental constituents and the concentrations. Each of the samples are bombarded with protons, which in result displaces a lower level electron and causes a higher level electron to fall into its place. This displacement produces characteristic x-rays that are `fingerprints' for each element. The protons supplied for the bombardment are produced and accelerated by the K150 proton beam in the Cyclotron Institute at Texas A&M University. The products are detected by three x-ray detectors: XR-100CR Si-PIN, XR-100SDD, and XR-100T CdTe. The peaks of the spectrum are analyzed using a software analysis tool, GUPIXWIN, to determine the concentration of the known elements of each particular sample. The goals of this work are to test run the Proton Induced X-Ray Emission experimental set up at Texas A&M University (TAMU) and to determine the concentration of thin films containing KBr given by the TAMU Chemical Engineering Department.

Exploring the use of environmental DNA to determine the species of salmon redds

USGS Publications Warehouse

Strobel, Burke; Laramie, Matthew; Pilliod, David S.

2017-01-01

Annual redd counts are used to monitor the status and trends of salmonid populations, but methods to easily and reliably determine which of sympatric species made specific redds are lacking. We explored whether environmental DNA (eDNA) analysis might prove useful for determining the species of salmon redds. We collected eDNA samples from the interstitial spaces of redds of Chinook Salmon Oncorhynchus tshawytscha, redds of Coho Salmon O. kisutch, and areas of undisturbed gravel (n = 10, each), as well as from the water column adjacent to each of those sites in the Sandy River basin, Oregon, USA during the fall of 2013. The concentrations of Chinook and Coho eDNA were quantified within each sample using real-time PCR. The water in the interstitial spaces of redds contained significantly higher eDNA concentrations of the species that made the redd than (1) the other species and (2) the adjacent water column. In contrast, neither Chinook nor Coho eDNA was significantly more concentrated than the other in the water from the interstitial spaces of undisturbed gravel. The interstitial water of undisturbed gravel contained significantly higher eDNA concentrations of Coho than the adjacent water column. In contrast, Chinook eDNA concentration was similar in the interstitial water of undisturbed gravel and the adjacent water column. Both species’ redds had significantly higher concentrations of their respective species’ eDNA than did undisturbed gravel, but conclusions were confounded by differences in the timing and locations of sampling. This initial investigation highlights the potential value and some of the complexity of using eDNA analysis to indicate redd species.

Boron contents and isotopic compositions of hog manure, selected fertilizers, and water in Minnesota

USGS Publications Warehouse

Komor, S.C.

1997-01-01

Boron-isotope (δ11B) values may be useful as surrogate tracers of contaminants and indicators of water mixing in agricultural settings. This paper characterizes the B contents and isotopic compositions of hog manure and selected fertilizers, and presents δ11B data for ground and surface water from two agricultural areas. Boron concentrations in dry hog manure averaged 61 mg/kg and in commercial fertilizers ranged from below detection limits in some brands of ammonium nitrate and urea to 382 mg/kg in magnesium sulfate. Values of δ11B of untreated hog manure ranged from 7.2 to 11.2o/oo and of N fertilizers were −2.0 to 0.7o/oo. In 22 groundwater samples from a sand-plain aquifer in east-central Minnesota, B concentrations averaged 0.04 mg/L and δ11B values ranged from 2.3 to 41.5o/oo. Groundwater beneath a hog feedlot and a cultivated field where hog manure was applied had B-isotope compositions consistent with the water containing hog-manure leachate. In a 775-km2 watershed with silty-loam soils in southcentral Minnesota: 18 samples of subsurface drainage from corn (Zea mays L.) and soybean (Glycine max L. Merr.) fields had average B concentrations of 0.06 mg/L and δ11B values of 5.3 to 15.1o/oo; 27 stream samples had average B concentrations of 0.05 mg/L and δ11B values of 1.0 to 19.0o/oo; and eight groundwater samples had average B concentrations of 0.09 mg/L and δ11B values of −0.3 to 23.0o/oo. Values of δ11B and B concentrations, when plotted against one another, define a curved mixing trend that suggests subsurface drainage and stream water contain mixtures of B from shallow and deep groundwater.

Trace Chemical Analysis Methodology

DTIC Science & Technology

1980-04-01

oxidation of nitrite-containing species. Calibration studies were then made in preparation for the analysis of unknown samples of nitrate in urine and...the procedure for nitrate determination was made on two types of samples : human urine , and drinking water from a city water supply. Five samples of...AND URINE Concentration Standard Sample type of NO3, ppm deviation Drinking water 1.29 ±0 04 1.20 ±0.09 1.29 ±0.14 1.15 ±0.08 0.88 ±0.07 Human urine

Immunoglobulin E-reactive proteins in cashew (Anacardium occidentale) apple juice concentrate.

PubMed

Comstock, Sarah S; Robotham, Jason M; Tawde, Pallavi; Kshirsagar, Harshal; Sathe, Shridhar K; Roux, Kenneth H; Teuber, Suzanne S

2008-07-23

Cashew apple juice has the potential to be a natural source of vitamin C and sugar in processed foods. The juice of the cashew apple is obtained by pressing the fleshy peduncle or receptacle, which forms a rounded apple that sits above the true fruit, the cashew nut. Cashew nut allergy is the second most commonly reported tree nut allergy in the United States. To determine if cashew apple juice contains cashew nut allergens, immunoblotting was performed using a cashew apple juice 6X concentrate that was extracted and further concentrated through dialysis, lyophilization, and resuspension. Serum IgE of individuals allergic to cashew nut bound proteins in the cashew apple juice concentrate extract. For some serum samples, IgE reactivity could be inhibited by preincubation of the serum with cashew nut extract, suggesting the presence of cashew nut-related allergens. Using monoclonal antibodies specific for cashew nut allergens, the concentrate was found to contain Ana o 1 (vicilin) and Ana o 2 (legumin). Neither IgE from cashew nut allergic sera nor the monoclonal antibodies bound any peptides in 5 kDa filtered cashew apple juice concentrate. The cashew apple juice concentrate used in these studies contains proteins with IgE-reactive epitopes, including cashew nut legumin and vicilin. No IgE-binding peptides remained after 5 kDa filtration of the concentrate.

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.

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.

Arsenic, Lead, and Cadmium in U.S. Mushrooms and Substrate in Relation to Dietary Exposure.

PubMed

Seyfferth, Angelia L; McClatchy, Colleen; Paukett, Michelle

2016-09-06

Wild mushrooms can absorb high quantities of metal(loid)s, yet the concentration, speciation, and localization of As, Pb, and Cd in cultivated mushrooms, particularly in the United States, are unresolved. We collected 40 samples of 12 types of raw mushrooms from 2 geographic locations that produce the majority of marketable U.S. mushrooms and analyzed the total As, Pb, and Cd content, the speciation and localization of As in select samples, and assessed the metal sources and substrate-to-fruit transfer at one representative farm. Cremini mushrooms contained significantly higher total As concentrations than Shiitake and localized the As differently; while As in Cremini was distributed throughout the fruiting body, it was localized to the hymenophore region in Shiitake. Cd was significantly higher in Royal Trumpet than in White Button, Cremini, and Portobello, while no difference was observed in Pb levels among the mushrooms. Concentrations of As, Pb, and Cd were less than 1 μg g(-1) d.w. in all mushroom samples, and the overall risk of As, Cd, and Pb intake from mushroom consumption is low in the U.S. However, higher percentages of tolerable intake levels are observed when calculating risk based on single serving-sizes or when substrate contains elevated levels of metal(loid)s.

Characterization of aerosols produced by cell sorters and evaluation of containment

PubMed Central

Holmes, Kevin L.

2011-01-01

In spite of the recognition by the flow cytometry community of potential aerosol hazards associated with cell sorting, there has been no previous study that has thoroughly characterized the aerosols that can be produced by cell sorters. In this study an Aerodynamic Particle Sizer was used to determine the concentration and aerodynamic diameter of aerosols produced by a FACS Aria II cell sorter under various conditions. Aerosol containment and evacuation was also evaluated using this novel methodology. The results showed that high concentrations of aerosols in the range of 1–3 μm can be produced in fail mode and that with decreased sheath pressure, aerosol concentration decreased and aerodynamic diameter increased. Although the engineering controls of the FACS Aria II for containment were effective, sort chamber evacuation of aerosols following a simulated nozzle obstruction was ineffective. However, simple modifications to the FACS Aria II are described that greatly improved sort chamber aerosol evacuation. The results of this study will facilitate the risk assessment of cell sorting potentially biohazardous samples by providing much needed data regarding aerosol production and containment. PMID:22052694

Human biomonitoring of aluminium after a single, controlled manual metal arc inert gas welding process of an aluminium-containing worksheet in nonwelders.

PubMed

Bertram, Jens; Brand, Peter; Hartmann, Laura; Schettgen, Thomas; Kossack, Veronika; Lenz, Klaus; Purrio, Ellwyn; Reisgen, Uwe; Kraus, Thomas

2015-10-01

Several existing field studies evaluate aluminium welding works but no thoroughly controlled exposure scenario for welding fume has been described yet. This study provides information about the uptake and elimination of aluminium from welding fumes under controlled conditions. In the Aachen Workplace Simulation Laboratory, we are able to generate welding fumes of a defined particle mass concentration. We exposed 12, until then occupationally unexposed participants with aluminium-containing welding fumes of a metal inert gas (MIG) welding process of a total dust mass concentration of 2.5 mg/m(3) for 6 h. Room air filter samples were collected, and the aluminium concentration in air derived. Urine and plasma samples were collected directly before and after the 6-h lasting exposure, as well as after 1 and 7 days. Human biomonitoring methods were used to determine the aluminium content of the samples with high-resolution continuum source atomic absorption spectrometry. Urinary aluminium concentrations showed significant changes after exposure compared to preexposure levels (mean t(1) (0 h) 13.5 µg/L; mean t(2) (6 h) 23.5 µg/L). Plasma results showed the same pattern but pre-post comparison did not reach significance. We were able to detect a significant increase of the internal aluminium burden of a single MIG aluminium welding process in urine, while plasma failed significance. Biphasic elimination kinetic can be observed. The German BAT of 60 µg/g creatinine was not exceeded, and urinary aluminium returned nearly to baseline concentrations after 7 days.

An analysis of using semi-permeable membrane devices to assess persistent organic pollutants in ambient air of Alaska

NASA Astrophysics Data System (ADS)

Wu, Ted Hsin-Yeh

A region of concern for persistent organic pollutants (POPS) contamination is the Arctic, because of POPs' ability to migrate long distances through the atmosphere toward cold regions, condense out of the atmosphere in those region, deposit in sensitive arctic ecosystems and bioaccumulate in Arctic species. Thus, monitoring of POP concentrations in the Arctic is necessary. However, traditional active air monitoring techniques for POPs may not be feasible in the Arctic, because of logistics and cost. While these issues may be overcome using passive air sampling devices, questions arise about the interpretation of the contaminant concentrations detected using the passive air samplers. In this dissertation semi-permeable membrane devices (SPMDs) containing triolein were characterized and evaluated for use in sampling the ambient air of Alaska for three classes of POPS (organochlorines [OCs], polychlorinated biphenyls [PCBs] and polyaromatic hydrocarbons [PAHs]). In addition, a SPMD-based sampling campaign for POPS was conducted simultaneously at five sites in Alaska during a one-year period. The POP concentrations obtained from the SPMDs were examined to determine the spatial and seasonal variability at the locations. POP concentrations detected in SPMDs were influenced by exposure to sunlight, concentrations of particulate-bound contaminants and changes in temperature. PAH concentrations in a SPMD mounted in a sunlight-blocking deployment unit were higher than in a SPMD exposed to sunlight (P = 0.007). PCB concentrations in SPMD exposed to filtered and non-filtered air were significantly different (P < 0.0001). Derived PAH air concentrations measured using SPMD were within a factor of approximately 7 of those obtained from an air sampler in Barrow, Alaska. The field study showed three distinct groups of samples. Barrow was separated from the sub-Arctic samples and a Homer sample (September-December) was distinct from the sub-Arctic samples. The separations suggest different air masses are being sampled by SPMDs. Lower concentrations of total POPs were measured at the coastal sites than the Interior sites.

Radioactivity concentration in liquid and solid phases of scale and sludge generated in the petroleum industry.

PubMed

Paranhos Gazineu, Maria Helena; de Araújo, Andressa Arruda; Brandão, Yana Batista; Hazin, Clovis Abrahão; de O Godoy, José Marcos

2005-01-01

Scales and sludge generated during oil extraction and production can contain uranium, thorium, radium and other natural radionuclides, which can cause exposure of maintenance personnel. This work shows how the oil content can influence the results of measurements of radionuclide concentration in scale and sludge. Samples were taken from a PETROBRAS unit in Northeast Brazil. They were collected directly from the inner surface of water pipes or from barrels stored in the waste storage area of the E&P unit. The oil was separated from the solids with a Soxhlet extractor by using aguarras at 90+/-5 degrees C as solvent. Concentrations of 226Ra and 228Ra in the samples were determined before and after oil extraction by using an HPGe gamma spectrometric system. The results showed an increase in the radionuclide concentration in the solid (dry) phase, indicating that the above radionuclides concentrate mostly in the solid material.

Marine sediment sample preparation for analysis for low concentrations of fine detrital gold

USGS Publications Warehouse

Clifton, H. Edward; Hubert, Arthur; Phillips, R. Lawrence

1967-01-01

Analyses by atomic absorption for detrital gold in more than 2,000 beach, offshore, marine-terrace, and alluvial sands from southern Oregon have shown that the values determined from raw or unconcentrated sediment containing small amounts of gold are neither reproducible nor representative of the initial sample. This difficulty results from a 'particle sparsity effect', whereby the analysis for gold in a given sample depends more upon the occurrence of random flakes of gold in the analyzed portion than upon the actual gold content of the sample. The particle sparsity effect can largely be eliminated by preparing a gold concentrate prior to analysis. A combination of sieve, gravimetric, and magnetic separation produces a satisfactory concentrate that yields accurate and reproducible analyses. In concentrates of nearly every marine and beach sand studied, the gold occurs in the nonmagnetic fraction smaller than 0.124 mm and with a specific gravity greater than 3.3. The grain size of gold in stream sediments is somewhat more variable. Analysis of concentrates provides a means of greatly increasing the sensitivity of the analytical technique in relation to the initial sample. Gold rarely exceeds 1 part per million in even the richest black sand analyzed; to establish the distribution of gold (and platinum) in marine sediments and its relationship to source and environmental factors, one commonly needs to know their content to the part per billion range. Analysis of a concentrate and recalculation to the value in the initial sample permits this degree of sensitivity.

Oxidation and mobilization of selenium by nitrate in irrigation drainage

USGS Publications Warehouse

Wright, W.G.

1999-01-01

Selenium (Se) can be oxidized by nitrate (NO3-) from irrigation on Cretaceous marine shale in western Colorado. Dissolved Se concentrations are positively correlated with dissolved NO3- concentrations in surface water and ground water samples from irrigated areas. Redox conditions dominate in the mobilization of Se in marine shale hydrogeologic settings; dissolved Se concentrations increase with increasing platinum-electrode potentials. Theoretical calculations for the oxidation of Se by NO3- and oxygen show favorable Gibbs free energies for the oxidation of Se by NO3-, indicating NO3- can act as an electron acceptor for the oxidation of Se. Laboratory batch experiments were performed by adding Mancos Shale samples to zero- dissolved-oxygen water containing 0, 5, 50, and 100 mg/L NO3- as N (mg N/L). Samples were incubated in airtight bottles at 25??C for 188 d; samples collected from the batch experiment bottles show increased Se concentrations over time with increased NO3- concentrations. Pseudo first-order rate constants for NO3- oxidation of Se ranged from 0.0007 to 0.0048/d for 0 to 100 mg N/L NO3- concentrations, respectively. Management of N fertilizer applications in Cretaceous shale settings might help to control the oxidation and mobilization of Se and other trace constituents into the environment.

Radionuclides, inorganic constitutents, organic compounds, and bacteria in water from selected wells and springs from the southern boundary of the Idaho National Engineering Laboratory to the Hagerman Area, Idaho, 1992

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

Bartholomay, R.C.; Edwards, D.D.; Campbell, L.J.

1994-11-01

The U.S. Geological Survey and the Idaho Department of Water Resources, in response to a request from the U.S. Department of Energy, sampled 18 sites as part of a long-term project to monitor water quality of the Snake River Plain aquifer from the southern boundary of the Idaho National Engineering Laboratory to the Hagerman area. Water samples were collected and analyzed for selected radionuclides, inorganic constituents, organic compounds, and bacteria. The samples were collected from 13 irrigation wells, 1 domestic well, 1 spring, 2 stock wells, and 1 public supply well. Quality assurance samples also were collected and analyzed. Nonemore » of the samples analyzed for radionuclides, inorganic constituents, or organic compounds exceeded the established maximum contaminant levels for drinking water. Most of the radionuclide and inorganic constituent concentrations exceeded their respective reporting levels. Most of the samples analyzed for surfactants and dissolved organic carbon had concentrations that exceeded their reporting levels. None of the samples contained reportable concentrations of purgeable organic compounds or pesticides. Total coliform bacteria was present in nine samples.« less

Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of organophosphate pesticides in filtered water by gas chromatography with flame photometric detection

USGS Publications Warehouse

Jha, Virendra K.; Wydoski, Duane S.

2002-01-01

A method for the isolation of 20 parent organophosphate pesticides and 5 pesticide degradates from filtered natural-water samples is described. Seven of these compounds are reported permanently with an estimated concentration because of performance issues. Water samples are filtered to remove suspended particulate matter, and then 1 liter of filtrate is pumped through disposable solid-phase extraction columns that contain octadecyl-bonded porous silica to extract the compounds. The C-18 columns are dried with nitrogen gas, and method compounds are eluted from the columns with ethyl acetate. The extract is analyzed by dual capillary-column gas chromatography with flame photometric detection. Single-operator method detection limits in all three water-matrix samples ranged from 0.004 to 0.012 microgram per liter. Method performance was validated by spiking all compounds into three different matrices at three different concentrations. Eight replicates were analyzed at each concentration level in each matrix. Mean recoveries of method compounds spiked in surface-water samples ranged from 39 to 149 percent and those in ground-water samples ranged from 40 to 124 percent for all pesticides except dimethoate. Mean recoveries of method compounds spiked in reagent-water samples ranged from 41 to 119 percent for all pesticides except dimethoate. Dimethoate exhibited reduced recoveries (mean of 43 percent in low- and medium-concentration level spiked samples and 20 percent in high-concentration level spiked samples) in all matrices because of incomplete collection on the C-18 column. As a result, concen-trations of dimethoate and six other compounds (based on performance issues) in samples are reported in this method with an estimated remark code.

Chemical and biological quality of surface water at the U.S. Army Atterbury Reserve Forces Training Area near Edinburgh, Indiana, September 2000 through July 2001

USGS Publications Warehouse

Risch, Martin R.

2004-01-01

A base-wide assessment of surface-water quality at the U.S. Army Atterbury Reserve Forces Training Area near Edinburgh, Indiana, examined short-term and long-term quality of surface water flowing into, across, and out of a 33,760-acre study area. The 30-day geometric-mean concentrations of fecal-indicator bacteria (Escherichia coli) in water samples from all 16 monitoring sites on streams in the study area were greater than the Indiana recreational water-quality standard. None of the bacteria concentrations in samples from four lakes exceeded the standard. Half the samples with bacteria concentrations greater than the single-sample standard contained chemical tracers potentially associated with human sewage. Increased turbidity of water samples was related statistically to increased bacteria concentration. Lead concentrations ranging from 0.5 to 2.0 micrograms per liter were detected in water samples at seven monitoring sites. Lead in one sample collected during high-streamflow conditions was greater than the calculated Indiana water-quality standard. With the exception of Escherichia coli and lead, 211 of 213 chemical constituents analyzed in water samples did not exceed Indiana water-quality standards. Out of 131 constituents analyzed in streambed-sediment and fish-tissue samples from three sites in the Common Impact Area for weapons training, the largest concentrations overall were detected for copper, lead, manganese, strontium, and zinc. Fish-community integrity, based on diversity and pollution tolerance, was rated poor at one of those three sites. Compared with State criteria, the fish-community data indicated 8 of 10 stream reaches in the study area could be categorized as "fully supporting" aquatic-life uses.

Chemistry and origin of minor and trace elements in selected vitrinite concentrates from bituminous and anthracitic coals

USGS Publications Warehouse

Palmer, C.A.; Lyons, P.C.

1990-01-01

Twelve hand-picked vitrinite concentrates and companion whole-coal samples were analyzed for trace and minor elements by instrumental neutron activation analysis (INAA) and direct-current-arc spectrographic techniques (DCAS). The vitrinite concentrates contained 94 to nearly 100 vol.% vitrinite compared to 71-95 vol.% in the companion whole coals. The ash contents of the vitrinite concentrates were 2 to more than 190 times less than the ash contents of the companion whole coals. Organic and inorganic affinities were determined by comparing the elemental concentrations in the vitrinite concentrates to the concentrations in the companion whole coals. The ratios of these concentrations for 33 selected elements are shown in Figure 1. Ratios greater than 1 indicate organic affinity, and ratios less than 1 indicate inorganic affinity. Br and W generally showed organic affinity in all samples in this study. In the nine samples from the eastern United States (Fig. 1A-C) less than one-fourth of the trace elements show organic affinity compared to nearly one-half for the three English and Australian samples (Fig. 1D). The elements that generally show organic affinity in the non-U.S.A. samples studied include As, Cs, Hf, and Ni, which have generally inorganic affinities in the U.S.A. samples, and Cr, Sb, Se, and U, which have mixed (both organic and inorganic) affinities, in the U.S.A. coals studied, has an inorganic affinity in the English coals studied. B shows organic affinity in the samples from the Illinois basin (Fig. 1C). For the samples studied, Ba shows organic affinity in the Appalachian basin bituminous coals (Fig. 1B), inorganic affinity in the Illinois basin coals, and overall mixed affinities. In all the samples studied, Cu, Mn, Na, Sr, Ta, V, and Zn show mixed affinities, and A1, Co, Eu, Fe, Ga, K, La, Mg, Sc, Si, Th, Ti, and Ub have generally inorganic affinity. ?? 1990.

Phenotypic and genotypic bacterial antimicrobial resistance in liquid pig manure is variously associated with contents of tetracyclines and sulfonamides.

PubMed

Hölzel, C S; Harms, K S; Küchenhoff, H; Kunz, A; Müller, C; Meyer, K; Schwaiger, K; Bauer, J

2010-05-01

Antibiotic residues as well as antibiotic-resistant bacteria in environmental samples might pose a risk to human health. This study aimed to investigate the association between antibiotic residues and bacterial antimicrobial resistance in liquid pig manure used as fertilizer. Concentrations of tetracyclines (TETs) and sulfonamides (SULs) were determined by liquid chromatography-mass spectrometry in 305 pig manure samples; antibiotic contents were correlated to the phenotypic resistance of Escherichia coli (n = 613) and enterococci (n = 564) towards up to 24 antibiotics. In 121 samples, the concentration of the TET resistance genes tet(M), tet(O) and tet(B) was quantified by real-time-PCR. TETs were found in 54% of the samples. The median sum concentration of all investigated TETs in the positive samples was 0.73 mg kg(-1). SULs were found with a similar frequency (51%) and a median sum concentration of 0.15 mg kg(-1) in the positive samples. Associated with the detection of TETs and/or SULs, resistance rates were significantly elevated for several substances - some of them not used in farm animals, e.g. chloramphenicol and synercid. In addition, multiresistant isolates were found more often in samples containing antibiotics. Analysis of the resistance genes tet(M) and tet(O) already showed a significant increase in their concentrations - but not in tet(B) - in the lowest range of total TET concentration. Mean tet(M) concentrations increased by the factor of 4.5 in the TET concentration range of 0.1-1 mg kg(-1), compared to negative manure samples. Antibiotic contamination of manure seems to be associated with a variety of changes in bacterial resistance, calling for a prudent use of antibiotics in farm animals. This study provides an interdisciplinary approach to assess antimicrobial resistance by combining the microbiological analysis of bacterial resistance with high quality chemical analysis of antibiotic residues in a representative number of environmental samples.

High resolution analysis of soil elements with laser-induced breakdown

DOEpatents

Ebinger, Michael H [Santa Fe, NM; Harris, Ronny D [Los Alamos, NM

2010-04-06

The invention is a system and method of detecting a concentration of an element in a soil sample wherein an opening or slot is formed in a container that supports a soil sample that was extracted from the ground whereupon at least a length of the soil sample is exposed via the opening. At each of a plurality of points along the exposed length thereof, the soil sample is ablated whereupon a plasma is formed that emits light characteristic of the elemental composition of the ablated soil sample. Each instance of emitted light is separated according to its wavelength and for at least one of the wavelengths a corresponding data value related to the intensity of the light is determined. As a function of each data value a concentration of an element at the corresponding point along the length of the soil core sample is determined.

Ground-water quality of the southern High Plains aquifer, Texas and New Mexico, 2001

USGS Publications Warehouse

Fahlquist, Lynne

2003-01-01

In 2001, the U.S. Geological Survey National Water-Quality Assessment Program collected water samples from 48 wells in the southern High Plains as part of a larger scientific effort to broadly characterize and understand factors affecting water quality of the High Plains aquifer across the entire High Plains. Water samples were collected primarily from domestic wells in Texas and eastern New Mexico. Depths of wells sampled ranged from 100 to 500 feet, with a median depth of 201 feet. Depths to water ranged from 34 to 445 feet below land surface, with a median depth of 134 feet. Of 240 properties or constituents measured or analyzed, 10 exceeded U.S. Environmental Protection Agency public drinking-water standards or guidelines in one or more samples - arsenic, boron, chloride, dissolved solids, fluoride, manganese, nitrate, radon, strontium, and sulfate. Measured dissolved solids concentrations in 29 samples were larger than the public drinking-water guideline of 500 milligrams per liter. Fluoride concentrations in 16 samples, mostly in the southern part of the study area, were larger than the public drinking-water standard of 4 milligrams per liter. Nitrate was detected in all samples, and concentrations in six samples were larger than the public drinking-water standard of 10 milligrams per liter. Arsenic concentrations in 14 samples in the southern part of the study area were larger than the new (2002) public drinking-water standard of 10 micrograms per liter. Radon concentrations in 36 samples were larger than a proposed public drinking-water standard of 300 picocuries per liter. Pesticides were detected at very small concentrations, less than 1 microgram per liter, in less than 20 percent of the samples. The most frequently detected compounds were atrazine and breakdown products of atrazine, a finding similar to those of National Water-Quality Assessment aquifer studies across the Nation. Four volatile organic compounds were detected at small concentrations in six water samples. About 70 percent of the 48 primarily domestic wells sampled contained some fraction of recently (less than about 50 years ago) recharged ground water, as indicated by the presence of one or more pesticides, or tritium or nitrate concentrations greater than threshold levels.

A Comparative study of microwave-induced pyrolysis of lignocellulosic and algal biomass.

PubMed

Wang, Nan; Tahmasebi, Arash; Yu, Jianglong; Xu, Jing; Huang, Feng; Mamaeva, Alisa

2015-08-01

Microwave (MW) pyrolysis of algal and lignocellulosic biomass samples were studied using a modified domestic oven. The pyrolysis temperature was recorded continuously by inserting a thermocouple into the samples. Temperatures as high as 1170 and 1015°C were achieved for peanut shell and Chlorella vulgaris. The activation energy for MW pyrolysis was calculated by Coats-Redfern method and the values were 221.96 and 214.27kJ/mol for peanut shell and C. vulgaris, respectively. Bio-oil yields reached to 27.7wt.% and 11.0wt.% during pyrolysis of C. vulgaris and peanut shell, respectively. The bio-oil samples from pyrolysis were analyzed by a gas chromatography-mass spectrometry (GC-MS). Bio-oil from lignocellulosic biomass pyrolysis contained more phenolic compounds while that from microalgae pyrolysis contained more nitrogen-containing species. Fourier transform infrared spectroscopy (FTIR) analysis results showed that concentration of OH, CH, CO, OCH3, and CO functional groups in char samples decreased significantly after pyrolysis. Copyright © 2015 Elsevier Ltd. All rights reserved.

High concentrations of furan fatty acids in organic butter samples from the German market.

PubMed

Wendlinger, Christine; Vetter, Walter

2014-08-27

Furan fatty acids (F-acids) are valuable antioxidants containing a furan moiety in the central part of the molecule. They occur in the lipids of different foodstuffs and plants, with grass being the main source for their presence in milk fat and butter. Because cows from organic farming receive higher portions of grass-based feed, it was tested whether organic butter samples (n = 26) contain more F-acids than conventional ones (n = 25) in Germany. For this purpose, samples were melted, and the lipid phase was separated and transesterified into methyl esters, which were enriched using silver ion chromatography and analyzed by GC-EI/MS in the selected ion monitoring (SIM) mode. Levels of F-acids in butter were higher in summer than in winter, and in both seasons, organic samples contained significantly higher levels of F-acids than conventional ones (one-way ANOVA: p < 0.001). Furthermore, the daily intake of F-acids via milk fat and other foodstuffs was calculated.

Determining baseline element composition of lichens. II. Hypogymnia enteromorpha and Usnea spp. at Redwood National Park, California

USGS Publications Warehouse

Gough, L.P.; Jackson, L.L.; Sacklin, J.A.

1988-01-01

Hypogymnia enteromorpha and Usnea spp. were collected in the Little Bald Hills ultramafic region of Redwood National Park, California, to establish element-concentration norms. Baselines are presented for Ba, Ca, Cu, Mn, Ni, P, Sr, V, and Zn for both lichen species; for Li, Mg, and K for H. enteromorpha; and for Al, Ce, Cr, Co, Fe, Na, and Ti for Usnea. Element concentrations of future collections of this same material can be used to monitor possible air quality changes anticipated from mining activities planned nearby. The variability in the element concentrations was partitioned between geographical distance increments and sample preparation and analysis procedures. In general, most of this variability was found in samples less than a few hundreds of meters apart rather than those at about 1 km apart. Therefore, except for Ba and Co, no large geographical element-concentration trends were observed. Samples of both species contained elevated levels of Ni and Mg, which probably reflect the ultramafic terrain over which they occur.

Fate of pharmaceutical and trace organic compounds in three septic system plumes, Ontario, Canada.

PubMed

Carrara, Cherilyn; Ptacek, Carol J; Robertson, William D; Blowes, David W; Moncur, Michael C; Sverko, Ed; Backus, Sean

2008-04-15

Three high volume septic systems in Ontario, Canada, were examined to assess the potential for onsite wastewatertreatment systems to release pharmaceutical compounds to the environment and to evaluate the mobility of these compounds in receiving aquifers. Wastewater samples were collected from the septic tanks, and groundwater samples were collected below and down gradient of the infiltration beds and analyzed for a suite of commonly used pharmaceutical and trace organic compounds. The septic tank samples contained elevated concentrations of several pharmaceutical compounds. Ten of the 12 compounds analyzed were detected in groundwater at one or more sites at concentrations in the low ng L(-1) to low microg L(-1) range. Large differences among the sites were observed in both the number of detections and the concentrations of the pharmaceutical compounds. Of the compounds analyzed, ibuprofen, gemfibrozil, and naproxen were observed to be transported atthe highest concentrations and greatest distances from the infiltration source areas, particularly in anoxic zones of the plumes.

BOREAS TGB-5 Dissolved Organic Carbon Data from NSA Beaver Ponds

NASA Technical Reports Server (NTRS)

Bourbonniere, Rick; Hall, Forrest G. (Editor); Conrad, Sara K. (Editor)

2000-01-01

The BOReal Ecosystem-Atmosphere Study Trace Gas Biogeochemistry (BOREAS TGB-5) team collected several data sets related to carbon and trace gas fluxes and concentrations in the Northern Study Area (NSA). This data set contains concentrations of dissolved organic and inorganic carbon species from water samples collected at various NSA sites. In particular, this set covers the NSA Tower Beaver Pond Site and the NSA Gillam Road Beaver Pond Site, including data from all visits to open water sampling locations during the BOREAS field campaigns from April to September 1994. The data are provided in tabular ASCII files.

[Antimony and other heavy metals in metallic kitchen ware].

PubMed

Ishiwata, H; Sugita, T; Yoshihira, K

1989-01-01

The antimony in metallic kitchen ware was determined. The content of this element in metals used for the production or repairing of utensils, containers and packaging which come in contact with foods is regulated and should be less than 5% in under the Japanese Food Sanitation Law. In eight metallic samples, antimony was detected in solder used for the production of a can for green tea and an eggbeater. The contents were 1.30% in the former and 1.90% in the latter. No antimony was detected in solder used for a cookie cutter. A sample of solder used for electric work, not for food utensils, contained 0.81% of antimony. In other metallic utensils which come in contact with food such as aluminum foil, a brass spoon, a stainless steel fork, a wire netting, and an iron rock for vegetable color stabilizing, antimony was not detected at a 0.05% detection limit. A qualitative test using rhodamine B also showed positive results in only three solder samples. Lead concentrations in solder used for the kitchen ware were from 39.3 to 51.3%. These concentrations were higher than the limit (20%) of lead content by the Law. No cadmium was detected in any samples.

A simple bubbling system for measuring radon (222Rn) gas concentrations in water samples based on the high solubility of radon in olive oil.

PubMed

Al-Azmi, D; Snopek, B; Sayed, A M; Domanski, T

2004-01-01

Based on the different levels of solubility of radon gas in organic solvents and water, a bubbling system has been developed to transfer radon gas, dissolving naturally in water samples, to an organic solvent, i.e. olive oil, which is known to be a good solvent of radon gas. The system features the application of a fixed volume of bubbling air by introducing a fixed volume of water into a flask mounted above the system, to displace an identical volume of air from an air cylinder. Thus a gravitational flow of water is provided without the need for pumping. Then, the flushing air (radon-enriched air) is directed through a vial containing olive oil, to achieve deposition of the radon gas by another bubbling process. Following this, the vial (containing olive oil) is measured by direct use of gamma ray spectrometry, without the need of any chemical or physical processing of the samples. Using a standard solution of 226Ra/222Rn, a lowest measurable concentration (LMC) of radon in water samples of 9.4 Bq L(-1) has been achieved (below the maximum contaminant level of 11 Bq L(-1)).

Mercury Speciation by X-ray Absorption Fine Structure Spectroscopy and Sequential Chemical Extractions: A Comparison of Speciation Methods

USGS Publications Warehouse

Kim, C.S.; Bloom, N.S.; Rytuba, J.J.; Brown, Gordon E.

2003-01-01

Determining the chemical speciation of mercury in contaminated mining and industrial environments is essential for predicting its solubility, transport behavior, and potential bioavailability as well as for designing effective remediation strategies. In this study, two techniques for determining Hg speciation-X-ray absorption fine structure (XAFS) spectroscopy and sequential chemical extractions (SCE)-are independently applied to a set of samples with Hg concentrations ranging from 132 to 7539 mg/kg to determine if the two techniques provide comparable Hg speciation results. Generally, the proportions of insoluble HgS (cinnabar, metacinnabar) and HgSe identified by XAFS correlate well with the proportion of Hg removed in the aqua regia extraction demonstrated to remove HgS and HgSe. Statistically significant (> 10%) differences are observed however in samples containing more soluble Hg-containing phases (HgCl2, HgO, Hg3S2O 4). Such differences may be related to matrix, particle size, or crystallinity effects, which could affect the apparent solubility of Hg phases present. In more highly concentrated samples, microscopy techniques can help characterize the Hg-bearing species in complex multiphase natural samples.

Evaluation of needle trap micro-extraction and automatic alveolar sampling for point-of-care breath analysis.

PubMed

Trefz, Phillip; Rösner, Lisa; Hein, Dietmar; Schubert, Jochen K; Miekisch, Wolfram

2013-04-01

Needle trap devices (NTDs) have shown many advantages such as improved detection limits, reduced sampling time and volume, improved stability, and reproducibility if compared with other techniques used in breath analysis such as solid-phase extraction and solid-phase micro-extraction. Effects of sampling flow (2-30 ml/min) and volume (10-100 ml) were investigated in dry gas standards containing hydrocarbons, aldehydes, and aromatic compounds and in humid breath samples. NTDs contained (single-bed) polymer packing and (triple-bed) combinations of divinylbenzene/Carbopack X/Carboxen 1000. Substances were desorbed from the NTDs by means of thermal expansion and analyzed by gas chromatography-mass spectrometry. An automated CO2-controlled sampling device for direct alveolar sampling at the point-of-care was developed and tested in pilot experiments. Adsorption efficiency for small volatile organic compounds decreased and breakthrough increased when sampling was done with polymer needles from a water-saturated matrix (breath) instead from dry gas. Humidity did not affect analysis with triple-bed NTDs. These NTDs showed only small dependencies on sampling flow and low breakthrough from 1-5 %. The new sampling device was able to control crucial parameters such as sampling flow and volume. With triple-bed NTDs, substance amounts increased linearly with increasing sample volume when alveolar breath was pre-concentrated automatically. When compared with manual sampling, automatic sampling showed comparable or better results. Thorough control of sampling and adequate choice of adsorption material is mandatory for application of needle trap micro-extraction in vivo. The new CO2-controlled sampling device allows direct alveolar sampling at the point-of-care without the need of any additional sampling, storage, or pre-concentration steps.

Characterization Results for the March 2016 H-Tank Farm 2H Evaporator Overhead Samples

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

Nicholson, J. C.

This report contains the radioanalytical results of the 2H evaporator overhead sample received at SRNL on March 16, 2016. Specifically, concentrations of 137Cs, 90Sr, and 129I are reported and compared to the corresponding Waste Acceptance Criteria (WAC) limits of the Effluent Treatment Project (ETP) Waste Water Collection Tank (WWCT) (rev. 6). All of the radionuclide concentrations in the sample were found to be in compliance with the ETP WAC limits. Revision 1 of this document corrects the cumulative beta count initially reported for 90Sr content with the sole 90Sr count obtained after recharacterization of the sample. The initial data wasmore » found to be a cumulative beta count rather than the 90Sr count requested.« less

U-Th-Pb systematics of some Apollo 16 lunar samples

NASA Technical Reports Server (NTRS)

Nunes, P. D.; Tatsumoto, M.; Knight, R. J.; Unruh, D. M.; Doe, B. R.

1973-01-01

U, Th, and Pb concentrations and lead isotopic compositions of Apollo 16 samples are interpreted as follows: (1) an early period of lunar differentiation of either global or regional scale occurred about 4.47 b.y. ago; (2) the Imbrian impact event affected many Apollo 16 samples about 3.99 b.y. ago; (3) some Apollo 16 metaclastic rocks and breccias contain a large amount of KREEP-like material; (4) lead produced in the early history of the moon has been concentrated in lunar highland soils yielding high Pb-207/Pb-206 ratios corresponding to apparent ages of more than 4.8 b.y.; and (5) South Ray Crater soils reflect the approximately 2-b.y.-old event previously proposed for the Apollo 12 and 14 samples.

Occurrence of organophosphorus and carbamate pesticide residues in surface water samples from the Rangpur district of Bangladesh.

PubMed

Chowdhury, Alamgir Zaman; Jahan, Salina Akter; Islam, Mohammad Nazrul; Moniruzzaman, Mohammed; Alam, Mohammad Khorshed; Zaman, Mohammad A; Karim, Nurul; Gan, Siew Hua

2012-07-01

We report the presence of organophosphorus and carbamate residues in 24 surface water samples and five ground water samples from Pirgacha Thana, Rangpur district, Bangladesh using high-performance liquid chromatography. A number of samples of surface water from paddy fields were found to contain chlorpyriphos, carbofuran and carbaryl at concentrations ranging from 0-1.189, 0-3.395 and 0-0.163 μg/L, respectively. Surface water from the lakes had chlorpyriphos, carbofuran and carbaryl at concentrations ranging from 0.544-0.895, 0.949-1.671 and 0-0.195 μg/L, respectively. This result indicates that the general public living in the area of Rangpur is at high risk of pesticide exposure from contaminated waters in the environment.

Water quality in Lake Lanier

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

Callaham, M.A.

1991-04-01

Thirteen water quality tests measuring five categories of pollution were conducted twice monthly from May, 1987 to April, 1990 at eight locations on Lake Sidney Lanier to establish baseline data and detect trends. Additionally, sediment and water samples were analyzed for ten toxic metals. Sampling stations were located at or near the point of entry of streams into the Lake. Oxygen demanding pollutants were highest in urban streams and phosphorus and nitrogen concentrations were highest in streams having poultry processing operations within their watersheds. Indicators of siltation increased coincidentally with highway construction in one watershed. Fecal coliform bacteria counts decreasedmore » at Flat Creek and increased in the Chattahoochee River. Zinc and copper occurred in water samples at levels of detectability. Sediment samples from several locations contained metal concentrations which warrant further study.« less

Selenium in waters in and adjacent to the Kendrick Project, Natrona County, Wyoming

USGS Publications Warehouse

Crist, Marvin A.

1975-01-01

Selenium in concentrations exceeding the maximum limit, 0.01 milligrams per liter or 10 micrograms per liter, recommended by the U.S. Public Health Service in 'Drinking-Water Standards, 1962,' Public Health Pub. 956, is present in waters in areas near Casper, Wyo. Some streams containing selenium flow into the North Platte River upstream from several municipalities that obtain water from the river and the alluvium along the river. The area of this investigation includes about 725 square miles in Natrona County in central Wyoming. Study effort was most intensive within the area bounded by the North Platte River, Casper Creek, and Casper Canal, the approximate boundaries of the Kendrick irrigation project. Geologic formations in the area contain selenium that may have been derived from deposits of seleniferous material or from volcanic emanations brought down by rain. Formations older than Cretaceous age were not considered as important sources of selenium in waters of the area, because no irrigation water is applied to areas underlain by these rocks. The selenium concentration in 82 samples of Cretaceous rocks ranged from less than 10 to 4,200 ?g/kg (micrograms per kilogram of sample); no correlation was found between selenium concentration and the depth at which the sample was collected. Of four samples of Tertiary rocks analyzed, three contained no selenium and one had a selenium concentration of 40 ?g/kg. The selenium concentration in 93 samples of Quaternary rocks ranged from less than 10 to 52.0 ?g/kg, and the highest selenium concentration was generally found at depths less than 4 feet. No geologic formation has consistently high concentrations of selenium, but high concentrations were found at points throughout the study area. Probably the rocks in any locality could be the source of selenium in the water in the surrounding vicinity. The selenium concentration in water from some wells fluctuates widely. It is concluded that the selenium concentrations in the ground water in these areas have not reached a state of equilibrium in the aquifer. It is possible that such nonequilibrium conditions exist in aquifers throughout much of the area. If so, statements in this report concerning- trends of selenium concentration in ground water are somewhat speculative.Poison Spring Creek, Poison Spider Creek, Oregon Trail Drain, and Casper Creek are the principal tributaries that contribute selenium to the North Platte River. The selenium load, expressed in pounds per day, in Poison Spring Creek and Poison Spider Creek decreased slightly during the first year of sampling and increased slightly during the second year of sampling. The selenium load in Oregon Trail Drain is greatest in late winter and early spring during the period of low flow; the selenium load in Casper Creek varies, but shows no correlation with season and little correlation with stream discharge. The North Platte River above and below the irrigation project had consistently low selenium concentrations, 10 ?g/l (micrograms per liter) or less, in the period April 1968 through June 1969. The total selenium load contributed to the North Platte River from tributaries in the study area is almost undetectable after mixing with the river water. From the fall of 1968 .to the spring of 1969, results of water sampling in areas influenced by irrigation show that the selenium concentration increased at 29 percent of the locations (average net increase of 64 ?g/l), decreased at 34 percent of the locations (average net decrease of 80 ?g/l), and had little (10 ?g/l or .less) or no change at 37 percent of the locations. As a comparison, results of water sampling in areas not influenced by irrigation showed that the selenium concentration increased at 2 percent of the locations (average net increase of 30 ?g/l), decreased at 26 percent of the locations (average net decrease of 30?g/l), and had little or no change at 72 percent of the locations. It is not possible to

Gas sampling system for reactive gas-solid mixtures

DOEpatents

Daum, Edward D.; Downs, William; Jankura, Bryan J.; McCoury, Jr., John M.

1989-01-01

An apparatus and method for sampling a gas containing a reactive particulate solid phase flowing through a duct and for communicating a representative sample to a gas analyzer. A sample probe sheath 32 with an angular opening 34 extends vertically into a sample gas duct 30. The angular opening 34 is opposite the gas flow. A gas sampling probe 36 concentrically located within sheath 32 along with calibration probe 40 partly extend in the sheath 32. Calibration probe 40 extends further in the sheath 32 than gas sampling probe 36 for purging the probe sheath area with a calibration gas during calibration.

Gas sampling system for reactive gas-solid mixtures

DOEpatents

Daum, Edward D.; Downs, William; Jankura, Bryan J.; McCoury, Jr., John M.

1990-01-01

An apparatus and method for sampling gas containing a reactive particulate solid phase flowing through a duct and for communicating a representative sample to a gas analyzer. A sample probe sheath 32 with an angular opening 34 extends vertically into a sample gas duct 30. The angular opening 34 is opposite the gas flow. A gas sampling probe 36 concentrically located within sheath 32 along with calibration probe 40 partly extends in the sheath 32. Calibration probe 40 extends further in the sheath 32 than gas sampling probe 36 for purging the probe sheath area with a calibration gas during calibration.

Freeze-Drying as Sample Preparation for Micellar Electrokinetic Capillary Chromatography – Electrochemical Separations of Neurochemicals in Drosophila Brains

PubMed Central

Berglund, E. Carina; Kuklinski, Nicholas J.; Karagündüz, Ekin; Ucar, Kubra; Hanrieder, Jörg; Ewing, Andrew G.

2013-01-01

Micellar electrokinetic capillary chromatography with electrochemical detection has been used to quantify biogenic amines in freeze-dried Drosophila melanogaster brains. Freeze drying samples offers a way to preserve the biological sample while making dissection of these tiny samples easier and faster. Fly samples were extracted in cold acetone and dried in a rotary evaporator. Extraction and drying times were optimized in order to avoid contamination by red-pigment from the fly eyes and still have intact brain structures. Single freeze-dried fly-brain samples were found to produce representative electropherograms as a single hand-dissected brain sample. Utilizing the faster dissection time that freeze drying affords, the number of brains in a fixed homogenate volume can be increased to concentrate the sample. Thus, concentrated brain samples containing five or fifteen preserved brains were analyzed for their neurotransmitter content, and five analytes; dopamine N-acetyloctopamine, Nacetylserotonin, N-acetyltyramine, N-acetyldopamine were found to correspond well with previously reported values. PMID:23387977

Ground-water quality in the Central High Plains Aquifer, Colorado, Kansas, New Mexico, Oklahoma, and Texas, 1999

USGS Publications Warehouse

Becker, Mark F.; Bruce, Breton W.; Pope, Larry M.; Andrews, William J.

2002-01-01

A network of 74 randomly distributed domestic water-supply wells completed in the central High Plains aquifer was sampled and analyzed from April to August 1999 as part of the High Plains Regional Ground-Water Study conducted by the U. S. Geological Survey National Water-Quality Assessment Program to provide a broad-scale assessment of the ground-water-quality in this part of the High Plains aquifer. Water properties were relatively consistent across the aquifer, with water being alkaline and well oxidized. Water was mostly of the calcium and magnesium-bicarbonate type and very hard. Sulfate concentrations in water from three wells and chloride concentration in water from one well exceeded Secondary Maximum Contaminant Levels. Fluoride concentration was equal to the Maximum Contaminant Level in one sample. Nitrate concentrations was relatively small in most samples, with the median concentration of 2.3 milligrams per liter. Dissolved organic carbon concentration was relatively low, with a median concentration of 0.5 milligram per liter. The Maximum Contaminant Level set by the U.S. Environmental Protection Agency for nitrate as nitrogen of 10 milligrams per liter was exceeded by water samples from three wells. Most samples contained detectable concentrations of the trace elements aluminum, arsenic, barium, chromium, molybdenum, selenium, zinc, and uranium. Only a few samples had trace element concentrations exceeding Maximum Contaminant Levels. Fifty-five of the samples had radon concentrations exceeding the proposed Maximum Contaminant Level of 300 picocuries per liter. The greatest radon concentrations were detected where the Ogallala Formation overlies sandstones, shales and limestones of Triassic, Jurassic, or Cretaceous age. Volatile organic compounds were detected in 9 of 74 samples. Toluene was detected in eight of those nine samples. All volatile organic compound concentrations were substantially less than Maximum Contaminant Levels. Detections of toluene may have been artifacts of the sampling and analytical processes. Pesticides were detected in 18 of the 74 water samples. None of the pesticide concentrations exceeded Maximum Contaminant Levels. The most frequently detected pesticides were atrazine and its metabolite deethylatrazine, which were detected in water from 15 and 17 wells, respectively. Most of the samples with a detectable pesticide had at least two detectable pesticides. Six of the samples had more than two detectable pesticides. Tritium concentrations was greater than 0.5 tritium unit in 10 of 51 samples, indicating recent recharge to the aquifer. Twenty-one of the samples that had nitrate concentrations greater than 4.0 milligrams per liter were assumed to have components of recent recharge. Detection of volatile organic compounds was not associated with those indicators of recent recharge, with most of volatile organic compounds being detected in water from wells with small tritium and nitrate concentrations. Detection of pesticides was associated with greater tritium or nitrate concentrations, with 16 of the 18 wells producing water with pesticides also having tritium or nitrate concentrations indicating recent recharge.

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.

Trapped noble gases indicate lunar origin for Antarctic meteorite

NASA Technical Reports Server (NTRS)

Bogard, D. D.; Johnson, P.

1983-01-01

The isotopic abundances of the noble gases (He, Ne, Ar, Kr, Xe) are reported for Antarctic ALHA 81005. It contains solar wind-implanted gases whose absolute and relative concentrations are quite similar to lunar regolith samples but not to other meteorites. ALHA 81005 also contains a large excess Ar-40 component which is identical to the component in lunar fines implanted from the lunar atmosphere. Large concentrations of cosmogenic Ne-21, Kr-82, and Xe-126 in ALHA 81005 indicate a total cosmic ray exposure age of at least 200 million years. The noble gas data alone are strong evidence for a lunar origin of this meteorite.

Concentration of infectious aquatic rhabdoviruses from freshwater and seawater using ultrafiltration.

PubMed

Grant, Amelia A M; Jakob, Eva; Richard, Jon; Garver, Kyle A

2011-12-01

Infectious hematopoietic necrosis virus (IHNV), viral hemorrhagic septicemia virus, and spring viremia of carp virus were concentrated and detected from freshwater and seawater samples by using hollow-fiber ultrafiltration. Within 60 min, virus in a 50-L freshwater or saltwater sample was concentrated more than 70-fold, and virus retention efficiencies were consistently greater than 88%. Retention efficiency was highly dependent upon concentrations of column blocking and sample stabilization solutions. A large column with a surface area of 1.15 m2 and a filtration capacity of 5-200 L exhibited optimal viral retention when blocked with 2% fetal bovine serum (FBS) and when the samples were supplemented with 0.1% FBS. Conversely, a small column with 100-fold less surface area and a filtering capacity of 0.5-2.0 L was optimized when blocked with 1% FBS and when the samples were supplemented with 0.1% FBS. The optimized ultrafiltration procedure was further validated with water from a tank that contained IHNV-exposed juvenile sockeye salmon Oncorhynchus nerka, resulting in an average virus retention efficiency of 91.6 +/- 4.1% (mean +/- SE). Virus quantification of concentrated samples demonstrated that IHNV shedding in sockeye salmon preceded mortality; shedding of the virus was observed to increase significantly as early as 7 d postchallenge and peaked at day 14, when virus levels reached 4.87 x 10(3) plaque-forming units/mL. We conclude that ultrafiltration is a reliable and effective method for concentrating viable aquatic rhabdoviruses from large volumes of water and has application for the analysis of environmental water samples.

Exposure to airborne asbestos in buildings

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

Lee, R.J.; Van Orden, D.R.; Corn, M.

The concentration of airborne asbestos in buildings and its implication for the health of building occupants is a major public health issue. A total of 2892 air samples from 315 public, commercial, residential, school, and university buildings has been analyzed by transmission electron microscopy. The buildings that were surveyed were the subject of litigation related to suits alleging the general building occupants were exposed to a potential health hazard as a result of exposure to the presence of asbestos containing materials (ACM). The average concentration of all asbestos structures was 0.02 structures/ml (s/ml) and the average concentration of asbestos greatermore » than or equal to 5 microns long was 0.00013 fibers/ml (f/ml). The concentration of asbestos was higher in schools than in other buildings. In 48% of indoor samples and 75% of outdoor samples, no asbestos fibers were detected. The observed airborne concentration in 74% of the indoor samples and 96% of the outdoor samples is below the Asbestos Hazard Emergency Response Act clearance level of 0.01 s/ml. Finally, using those fibers which could be seen optically, all indoor samples and all outdoor samples are below the Occupational Safety and Health Administration permissible exposure level of 0.1 f/ml for fibers greater than or equal to 5 microns in length. These results provide substantive verification of the findings of the U.S. Environmental Protection Agency public building study which found very low ambient concentrations of asbestos fibers in buildings with ACM, irrespective of the condition of the material in the buildings.« less

A Comparison Study of Sampling and Analyzing Volatile Organic Compounds in Air in Kuwait by Using Tedlar Bags/Canisters and GC-MS with a Cryogenic Trap

PubMed Central

Tang, Hongmao; Beg, Khaliq R.; Al-Otaiba, Yousef

2006-01-01

Kuwait experiences desert climatic weather. Due to the extreme hot and dry conditions in this country, some analytical phenomena have been discovered. Therefore, a systematic study of sampling and analyzing volatile organic compounds in air by using GC-MS with a cryogenic trap is reported in this paper. This study included comparisons of using different sample containers such as Tedlar bags and SUMMA canisters, and different cryogenic freezing-out air volumes in the trap. Calibration curves for different compounds and improvement of replicated analysis results were also reported here. The study found that using different sample containers produced different results. Analysis of ambient air samples collected in Tedlar bags obtained several volatile organic compounds with large concentrations compared to using SUMMA canisters. Therefore, to choose a sample container properly is a key element for successfully completing a project. Because GC-MS with a cryogenic trap often generates replicated results with poor agreement, an internal standard added to gas standards and air samples by using a gas syringe was tested. The study results proved that it helped to improve the replicated results. PMID:16699723

A comparison study of sampling and analyzing volatile organic compounds in air in Kuwait by using Tedlar bags/canisters and GC-MS with a cryogenic trap.

PubMed

Tang, Hongmao; Beg, Khaliq R; Al-Otaiba, Yousef

2006-05-12

Kuwait experiences desert climatic weather. Due to the extreme hot and dry conditions in this country, some analytical phenomena have been discovered. Therefore, a systematic study of sampling and analyzing volatile organic compounds in air by using GC-MS with a cryogenic trap is reported in this paper. This study included comparisons of using different sample containers such as Tedlar bags and SUMMA canisters, and different cryogenic freezing-out air volumes in the trap. Calibration curves for different compounds and improvement of replicated analysis results were also reported here. The study found that using different sample containers produced different results. Analysis of ambient air samples collected in Tedlar bags obtained several volatile organic compounds with large concentrations compared to using SUMMA canisters. Therefore, to choose a sample container properly is a key element for successfully completing a project. Because GC-MS with a cryogenic trap often generates replicated results with poor agreement, an internal standard added to gas standards and air samples by using a gas syringe was tested. The study results proved that it helped to improve the replicated results.

Suitability of shredded tyres as a substitute for a landfill leachate collection medium.

PubMed

Park, Jae K; Edil, Tuncer B; Kim, Jae Y; Huh, Mock; Lee, Sung Ho; Lee, Jung Jun

2003-06-01

A series of tests were conducted to investigate the fate of heavy metals and gasoline components in a simulated landfill, consisting of a 30 cm thick clay liner and a leachate collection layer containing tyres as well as in two test cells installed in a landfill. Arsenic, selenium, mercury, barium, and lead concentrations were lower while zinc concentration was higher in the tank containing tyre-chips than the tank without tyre-chips. When samples were filtered, however, concentrations of zinc as well as other inorganics were lower in the tank containing tyre-chips, indicating that metals in the leachate exposed to tyre-chips travel more slowly in a subsurface environment due to filtering effect. In a test cell study, arsenic, cobalt, lead and nickel concentrations were lower in the cell containing tyre-chips than in the cell without tyre-chips, except iron and zinc. Both tests indicate that some inorganic contaminants are sorbed to tyre-chips. Gasoline components were also significantly sorbed by tyre-chips in field cell tests. Although tyre-chips are known to leach organic and inorganic contaminants, concentrations in field conditions will be lower than the reported experimental results since the tests were performed under worst-case scenarios. If tyre-chips are used in areas where contamination levels are high, then they can be used as a sorbent for environmental clean-up.

Data on Streamflow and Quality of Water and Bottom Sediment in and near Humboldt Wildlife Management Area, Churchill and Pershing Counties, Nevada, 1998-2000

USGS Publications Warehouse

Paul, Angela P.; Thodal, Carl E.

2003-01-01

This study was initiated to expand upon previous findings that indicated concentrations of dissolved solids, arsenic, boron, mercury, molybdenum, selenium, and uranium were either above geochemical background concentrations or were approaching or exceeding ecological criteria in the lower Humboldt River system. Data were collected from May 1998 to September 2000 to further characterize streamflow and surface-water and bottom-sediment quality in the lower Humboldt River, selected agricultural drains, Upper Humboldt Lake, and Lower Humboldt Drain (ephemeral outflow from Humboldt Sink). During this study, flow in the lower Humboldt River was either at or above average. Flows in Army and Toulon Drains generally were higher than reported in previous investigations. An unnamed agricultural drain contributed a small amount to the flow measured in Army Drain. In general, measured concentrations of sodium, chloride, dissolved solids, arsenic, boron, molybdenum, and uranium were higher in water from agricultural drains than in Humboldt River water during this study. Mercury concentrations in water samples collected during the study period typically were below the laboratory reporting level. However, low-level mercury analyses showed that samples collected in August 1999 from Army Drain had higher mercury concentrations than those collected from the river or Toulon Drain or the Lower Humboldt Drain. Ecological criteria and effect concentrations for sodium, chloride, dissolved solids, arsenic, boron, mercury, and molybdenum were exceeded in some water samples collected as part of this study. Although water samples from the agricultural drains typically contained higher concentrations of sodium, chloride, dissolved solids, arsenic, boron, and uranium, greater instantaneous loads of these constituents were carried in the river near Lovelock than in agricultural drains during periods of high flow or non-irrigation. During this study, the high flows in the lower Humboldt River produced the maximum instantaneous loads of sodium, chloride, dissolved solids, arsenic, boron, molybdenum, and uranium at all river-sampling sites, except molybdenum near Imlay. Nevada Division of Environmental Protection monitoring reports on mine-dewatering discharge for permitted releases of treated effluent to the surface waters of the Humboldt River and its tributaries were reviewed for reported discharges and trace-element concentrations from June 1998 to September 1999. These data were compared with similar information for the river near Imlay. In all bottom sediments collected for this study, arsenic concentrations exceeded the Canadian Freshwater Interim Sediment-Quality Guideline for the protection of aquatic life and probable-effect level (concentration). Sediments collected near Imlay, Rye Patch Reservoir, Lovelock, and from Toulon Drain and Army Drain were found to contain cadmium and chromium concentrations that exceeded Canadian criteria. Chromium concentrations in sediments collected from these sites also exceeded the consensus-based threshold-effect concentration. The Canadian criterion for sediment copper concentration was exceeded in sediments collected from the Humboldt River near Lovelock and from Toulon, Army, and the unnamed agricultural drains. Mercury in sediments collected near Imlay and from Toulon Drain in August 1999 exceeded the U.S. Department of the Interior sediment probable-effect level. Nickel concentrations in sediments collected during this study were above the consensus-based threshold-effect concentration. All other river and drain sediments had constituent concentrations below protective criteria and toxicity thresholds. In Upper Humboldt Lake, chloride, dissolved solids, arsenic, boron, molybdenum, and uranium concentrations in surface-water samples collected near the mouth of the Humboldt River generally were higher than in samples collected near the mouth of Army Drain. Ecological criteria or effect con

Acquisition of Cry1Ac Protein by Non-Target Arthropods in Bt Soybean Fields

PubMed Central

Yu, Huilin; Romeis, Jörg; Li, Yunhe; Li, Xiangju; Wu, Kongming

2014-01-01

Soybean tissue and arthropods were collected in Bt soybean fields in China at different times during the growing season to investigate the exposure of arthropods to the plant-produced Cry1Ac toxin and the transmission of the toxin within the food web. Samples from 52 arthropod species/taxa belonging to 42 families in 10 orders were analysed for their Cry1Ac content using enzyme-linked immunosorbent assay (ELISA). Among the 22 species/taxa for which three samples were analysed, toxin concentration was highest in the grasshopper Atractomorpha sinensis and represented about 50% of the concentration in soybean leaves. Other species/taxa did not contain detectable toxin or contained a concentration that was between 1 and 10% of that detected in leaves. These Cry1Ac-positive arthropods included a number of mesophyll-feeding Hemiptera, a cicadellid, a curculionid beetle and, among the predators, a thomisid spider and an unidentified predatory bug belonging to the Anthocoridae. Within an arthropod species/taxon, the Cry1Ac content sometimes varied between life stages (nymphs/larvae vs. adults) and sampling dates (before, during, and after flowering). Our study is the first to provide information on Cry1Ac-expression levels in soybean plants and Cry1Ac concentrations in non-target arthropods in Chinese soybean fields. The data will be useful for assessing the risk of non-target arthropod exposure to Cry1Ac in soybean. PMID:25110881

In situ Spectroscopic Analysis and Quantification of [Tc(CO)3]+ in Hanford Tank Waste.

PubMed

Branch, Shirmir D; French, Amanda D; Lines, Amanda M; Soderquist, Chuck Z; Rapko, Brian M; Heineman, William R; Bryan, Samuel A

2018-06-12

The quantitative conversion of non-pertechnetate [Tc(CO)3]+ species in nuclear waste storage tank 241-AN-102 at the Hanford Site is demonstrated. A waste sample containing the [Tc(CO)3]+ species is added to a developer solution that rapidly converts the non-emissive species into a luminescent complex, which is detected spectroscopically. This method was first demonstrated using a [Tc(CO)3]+ sample non-waste containing matrix to determine a detection limit (LOD), resulting in a [Tc(CO)3]+ LOD of 2.20 × 10-7 M, very near the LOD of the independently synthesized standard (2.10 × 10-7 M). The method was then used to detect [Tc(CO)3]+ in a simulated waste using the standard addition method, resulting in a [Tc(CO)3]+ concentration of 1.89 × 10-5 M (within 27.7% of the concentration determined by β- liquid scintillation counting). Three samples from 241-AN-102 were tested by the standard addition method: (1) a 5 M Na adjusted fraction, (2) a fraction depleted of 137Cs, (3) and an acid-stripped eluate. The concentrations of [Tc(CO)3]+ in these fractions were determined to be 9.90 × 10-6 M (1), 0 M (2), and 2.46 × 10-6 M (3), respectively. The concentration of [Tc(CO)3]+ in the as-received AN-102 tank waste supernatant was determined to be 1.84 × 10-5 M.

Drinking water fluoride levels for a city in northern Mexico (durango) determined using a direct electrochemical method and their potential effects on oral health.

PubMed

Molina Frechero, Nelly; Sánchez Pérez, Leonor; Castañeda Castaneira, Enrique; Oropeza Oropeza, Anastasio; Gaona, Enrique; Salas Pacheco, José; Bologna Molina, Ronell

2013-01-01

Fluoride is ingested primarily through consuming drinking water. When drinking water contains fluoride concentrations>0.7 parts per million (ppm), consuming such water can be toxic to the human body; this toxicity is called "fluorosis." Therefore, it is critical to determine the fluoride concentrations in drinking water. The objective of this study was to determine the fluoride concentration in the drinking water of the city of Durango. The wells that supply the drinking water distribution system for the city of Durango were studied. One hundred eighty-nine (189) water samples were analyzed, and the fluoride concentration in each sample was quantified as established by the law NMX-AA-077-SCFI-2001. The fluoride concentrations in such samples varied between 2.22 and 7.23 ppm with a 4.313±1.318 ppm mean concentration. The highest values were observed in the northern area of the city, with a 5.001±2.669 ppm mean value. The samples produced values that exceeded the national standard for fluoride in drinking water. Chronic exposure to fluoride at such concentrations produces harmful health effects, the first sign of which is dental fluorosis. Therefore, it is essential that the government authorities implement water defluoridation programs and take preventative measures to reduce the ingestion of this toxic halogen.

Drinking Water Fluoride Levels for a City in Northern Mexico (Durango) Determined Using a Direct Electrochemical Method and Their Potential Effects on Oral Health

PubMed Central

Molina Frechero, Nelly; Sánchez Pérez, Leonor; Castañeda Castaneira, Enrique; Oropeza Oropeza, Anastasio; Gaona, Enrique; Salas Pacheco, José; Bologna Molina, Ronell

2013-01-01

Fluoride is ingested primarily through consuming drinking water. When drinking water contains fluoride concentrations >0.7 parts per million (ppm), consuming such water can be toxic to the human body; this toxicity is called “fluorosis.” Therefore, it is critical to determine the fluoride concentrations in drinking water. The objective of this study was to determine the fluoride concentration in the drinking water of the city of Durango. The wells that supply the drinking water distribution system for the city of Durango were studied. One hundred eighty-nine (189) water samples were analyzed, and the fluoride concentration in each sample was quantified as established by the law NMX-AA-077-SCFI-2001. The fluoride concentrations in such samples varied between 2.22 and 7.23 ppm with a 4.313 ± 1.318 ppm mean concentration. The highest values were observed in the northern area of the city, with a 5.001 ± 2.669 ppm mean value. The samples produced values that exceeded the national standard for fluoride in drinking water. Chronic exposure to fluoride at such concentrations produces harmful health effects, the first sign of which is dental fluorosis. Therefore, it is essential that the government authorities implement water defluoridation programs and take preventative measures to reduce the ingestion of this toxic halogen. PMID:24348140

Detection of zinc oxide and cerium dioxide nanoparticles during drinking water treatment by rapid single particle ICP-MS methods.

PubMed

Donovan, Ariel R; Adams, Craig D; Ma, Yinfa; Stephan, Chady; Eichholz, Todd; Shi, Honglan

2016-07-01

Nanoparticles (NPs) entering water systems are an emerging concern as NPs are more frequently manufactured and used. Single particle inductively coupled plasma-mass spectrometry (SP-ICP-MS) methods were validated to detect Zn- and Ce-containing NPs in surface and drinking water using a short dwell time of 0.1 ms or lower, ensuring precision in single particle detection while eliminating the need for sample preparation. Using this technique, information regarding NP size, size distribution, particle concentration, and dissolved ion concentrations was obtained simultaneously. The fates of Zn- and Ce-NPs, including those found in river water and added engineered NPs, were evaluated by simulating a typical drinking water treatment process. Lime softening, alum coagulation, powdered activated carbon sorption, and disinfection by free chlorine were simulated sequentially using river water. Lime softening removed 38-53 % of Zn-containing and ZnO NPs and >99 % of Ce-containing and CeO2 NPs. Zn-containing and ZnO NP removal increased to 61-74 % and 77-79 % after alum coagulation and disinfection, respectively. Source and drinking water samples were collected from three large drinking water treatment facilities and analyzed for Zn- and Ce-containing NPs. Each facility had these types of NPs present. In all cases, particle concentrations were reduced by a minimum of 60 % and most were reduced by >95 % from source water to finished drinking water. This study concludes that uncoated ZnO and CeO2 NPs may be effectively removed by conventional drinking water treatments including lime softening and alum coagulation.

Soil data from Picea mariana stands near delta junction, Alaska of different ages and soil drainage type

USGS Publications Warehouse

Manies, Kristen L.; Harden, Jennifer W.; Silva, Steven R.; Briggs, Paul H.; Schmid, Brian M.

2004-01-01

The U.S. Geological Survey project Fate of Carbon in Alaskan Landscapes (FOCAL) is studying the effect of fire and soil drainage on soil carbon storage in the boreal forest. This project has selected several sites to study within central Alaska of varying ages (time since fire) and soil drainage types. This report describes the location of these sampling sites, as well as the procedures used to describe, sample, and analyze the soils. This report also contains data tables with this information, including, but not limited to field descriptions, bulk density, particle size distribution, moisture content, carbon (C) concentration, nitrogen (N) concentration, isotopic data for C, and major, minor and trace elemental concentration.

Variation in aluminum, iron, and particle concentrations in oxic groundwater samples collected by use of tangential-flow ultrafiltration with low-flow sampling

NASA Astrophysics Data System (ADS)

Szabo, Zoltan; Oden, Jeannette H.; Gibs, Jacob; Rice, Donald E.; Ding, Yuan

2002-02-01

Particulates that move with ground water and those that are artificially mobilized during well purging could be incorporated into water samples during collection and could cause trace-element concentrations to vary in unfiltered samples, and possibly in filtered samples (typically 0.45-um (micron) pore size) as well, depending on the particle-size fractions present. Therefore, measured concentrations may not be representative of those in the aquifer. Ground water may contain particles of various sizes and shapes that are broadly classified as colloids, which do not settle from water, and particulates, which do. In order to investigate variations in trace-element concentrations in ground-water samples as a function of particle concentrations and particle-size fractions, the U.S. Geological Survey, in cooperation with the U.S. Air Force, collected samples from five wells completed in the unconfined, oxic Kirkwood-Cohansey aquifer system of the New Jersey Coastal Plain. Samples were collected by purging with a portable pump at low flow (0.2-0.5 liters per minute and minimal drawdown, ideally less than 0.5 foot). Unfiltered samples were collected in the following sequence: (1) within the first few minutes of pumping, (2) after initial turbidity declined and about one to two casing volumes of water had been purged, and (3) after turbidity values had stabilized at less than 1 to 5 Nephelometric Turbidity Units. Filtered samples were split concurrently through (1) a 0.45-um pore size capsule filter, (2) a 0.45-um pore size capsule filter and a 0.0029-um pore size tangential-flow filter in sequence, and (3), in selected cases, a 0.45-um and a 0.05-um pore size capsule filter in sequence. Filtered samples were collected concurrently with the unfiltered sample that was collected when turbidity values stabilized. Quality-assurance samples consisted of sequential duplicates (about 25 percent) and equipment blanks. Concentrations of particles were determined by light scattering.

Improved COD Measurements for Organic Content in Flowback Water with High Chloride Concentrations.

PubMed

Cardona, Isabel; Park, Ho Il; Lin, Lian-Shin

2016-03-01

An improved method was used to determine chemical oxygen demand (COD) as a measure of organic content in water samples containing high chloride content. A contour plot of COD percent error in the Cl(-)-Cl(-):COD domain showed that COD errors increased with Cl(-):COD. Substantial errors (>10%) could occur in low Cl(-):COD regions (<300) for samples with low (<10 g/L) and high chloride concentrations (>25 g/L). Applying the method to flowback water samples resulted in COD concentrations ranging in 130 to 1060 mg/L, which were substantially lower than the previously reported values for flowback water samples from Marcellus Shale (228 to 21 900 mg/L). It is likely that overestimations of COD in the previous studies occurred as result of chloride interferences. Pretreatment with mercuric sulfate, and use of a low-strength digestion solution, and the contour plot to correct COD measurements are feasible steps to significantly improve the accuracy of COD measurements.

Tracing the origin of pollution in French Alpine snow and aerosols using lead isotopic ratios.

PubMed

Veysseyre, A M; Bollhöfer, A F; Rosman, K J; Ferrari, C P; Boutron, C F

2001-11-15

Fresh snow samples collected at 15 remote locations and aerosols collected at one location in the French Alps between November 1998 and April 1999 have been analyzed for Pb concentration and isotopic composition by thermal ionization mass spectrometry. The snow samples contained 19-1300 pg/g of Pb with isotopic ratios 206Pb/207Pb (208Pb/207Pb) of 1.1279-1.1607 (2.3983-2.4302). Airborne Pb concentrations at one sampling site ranged from 0.42 to 6.0 ng/m3 with isotopic ratios of 1.1321-1.1427 (2.4029-2.4160). Air mass trajectory analysis combined with isotopic compositions of potential source regions did not show discernible evidence of the long-range atmospheric transport of pollutants. Isotopic ratios in the Alpine snow samples and thus the free troposphere were generally higher than airborne Pb isotopic ratios in urban France, which coupled with the relatively high Pb concentrations suggested a regional anthropogenic Pb source, probably Italy but possibly Eastern Europe.

Elemental concentrations and bioaccessibilities in beached plastic foam litter, with particular reference to lead in polyurethane.

PubMed

Turner, Andrew; Lau, Kwan S

2016-11-15

Seventy samples of foamed plastic collected from a high-energy, sandy beach in SW England have been characterised by FTIR and XRF. Most samples were polyurethane (PU; n=39) or polystyrene (PS; n=27) that were associated with variable concentrations of Br-Cl, Fe and Zn, indicative of the presence of halogenated flame retardants, iron oxides and Zn-based additives, respectively. Many samples of rigid PU contained Pb, historically used as a catalyst, at concentrations of up to 16,000μgg -1 . A physiological extraction test that simulates the conditions in the gizzard of plastic-ingesting seabirds was applied to selected samples and results revealed that while Br and Zn were not measurably bioaccessible, Pb mobilisation progressed logarithmically over a period of time with maximum accessibilities after 220h of ~10% of total metal. Foamed PU is a source of bioaccessible Pb in the marine environment that has not previously been documented. Copyright © 2016 Elsevier Ltd. All rights reserved.

Variation in commercial smoking mixtures containing third-generation synthetic cannabinoids.

PubMed

Frinculescu, Anca; Lyall, Catherine L; Ramsey, John; Miserez, Bram

2017-02-01

Variation in ingredients (qualitative variation) and in quantity of active compounds (quantitative variation) in herbal smoking mixtures containing synthetic cannabinoids has been shown for older products. This can be dangerous to the user, as accurate and reproducible dosing is impossible. In this study, 69 packages containing third-generation cannabinoids of seven brands on the UK market in 2014 were analyzed both qualitatively and quantitatively for variation. When comparing the labels to actual active ingredients identified in the sample, only one brand was shown to be correctly labelled. The other six brands contained less, more, or ingredients other than those listed on the label. Only two brands were inconsistent, containing different active ingredients in different samples. Quantitative variation was assessed both within one package and between several packages. Within-package variation was within a 10% range for five of the seven brands, but two brands showed larger variation, up to 25% (Relative Standard Deviation). Variation between packages was significantly higher, with variation up to 38% and maximum concentration up to 2.7 times higher than the minimum concentration. Both qualitative and quantitative variation are common in smoking mixtures and endanger the user, as it is impossible to estimate the dose or to know the compound consumed when smoking commercial mixtures. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.