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1

ANALYTICAL REFERENCE STANDARDS AND SUPPLEMENTAL DATA FOR PESTICIDES AND OTHER ORGANIC COMPOUNDS  

EPA Science Inventory

;Contents: List of available pesticide standards and ordering information; Compounds deleted from 1978 stock and name changes; List of non-pesticide organic chemical standards; Safe handling of primary reference standards; Preparation and storage of reference standards; Decoding ...

2

Organic Pesticide Ingredients  

MedlinePLUS

... Organic and Conventionally Grown Food Food Safety Minimizing Pesticide Residues in Food Share this page: We are open from 8:00am to 12:00pm Pacific time Mon. — Fri. Please read our disclaimer | Contact ... objective, science-based information about pesticides and pesticide-related topics to enable people to ...

3

Relations between Land Use and Organochlorine Pesticides, PCBs, and Semi-Volatile Organic Compounds in Streambed Sediment and Fish on the Island of Oahu, Hawaii  

USGS Publications Warehouse

Bed-sediment and/or fish samples were collected from 27 sites around the island of Oahu (representing urban, agricultural, mixed, and forested land use) to determine the occurrence and distribution of hydrophobic organic compounds including organochlorine pesticides, polychlorinated biphenyls (PCBs), and semi-volatile organic compounds (SVOCs). Of the 28 organochlorine compounds analyzed in the fish, 14 were detected during this study. Nineteen of the 31 organochlorine compounds and 40 of the 65 SVOCs were detected in the sediment. Urban sites had the highest number of detections and tended to have the highest concentrations of pesticides. Chlordane compounds were the most frequently detected constituents at urban sites, followed by dieldrin, polycyclic aromatic hydrocarbons (PAHs), and DDT compounds. PAHs were the most frequently detected constituents in watersheds with mixed (urban and agricultural) land use. The only pesticides detected at agricultural sites were DDT and its degradation products, DDD and DDE. No pesticides or PCBs were detected at the forested sites, but a few ubiquitous SVOCs were found in sediments at some forested sites. In general, concentrations of the most frequently detected pesticides were higher in fish than in sediment. Following a trend that has been observed elsewhere in the nation, concentrations of most organochlorine pesticides and PCBs are decreasing in Hawaii.

Brasher, A.M.D.; Wolff, R.H.

2004-01-01

4

Applicability of Polar Organic Compounds Integrative Samplers for monitoring pesticides in groundwater  

E-print Network

in groundwater Catherine Berho*a , Anne Togola a , Charlotte Coureau a , Jean-Philippe Ghestem a , Laurence Chemical Integrative Samplers (POCIS) for the monitoring of polar pesticides in groundwater were tested-flow conditions for a relevant quantification of pesticides in groundwater and to establish more representative

Paris-Sud XI, Université de

5

Occurrence of Selected Pharmaceuticals, Personal-Care Products, Organic Wastewater Compounds, and Pesticides in the Lower Tallapoosa River Watershed near Montgomery, Alabama, 2005  

USGS Publications Warehouse

Synthetic and natural organic compounds derived from agricultural operations, residential development, and treated and untreated sanitary and industrial wastewater discharges can contribute contaminants to surface and ground waters. To determine the occurrence of these compounds in the lower Tallapoosa River watershed, Alabama, new laboratory methods were used that can detect human and veterinary antibiotics; pharmaceuticals; and compounds found in personal-care products, food additives, detergents and their metabolites, plasticizers, and other industrial and household products in the environment. Well-established methods for detecting 47 pesticides and 19 pesticide degradates also were used. In all, 186 different compounds were analyzed by using four analytical methods. The lower Tallapoosa River serves as the water-supply source for more than 100,000 customers of the Montgomery Water Works and Sanitary Sewer Board. Source-water protection is a high priority for the Board, which is responsible for providing safe drinking water. The U.S. Geological Survey, in cooperation with the Montgomery Water Works and Sanitary Sewer Board, conducted this study to provide baseline data that could be used to assess the effects of agriculture and residential development on the occurrence of selected organic compounds in the lower Tallapoosa River watershed. Twenty samples were collected at 10 sites on the Tallapoosa River and its tributaries. Ten samples were collected in April 2005 during high base streamflow, and 10 samples were collected in October 2005 when base streamflow was low. Thirty-two of 186 compounds were detected in the lower Tallapoosa River watershed. Thirteen compounds, including atrazine, 2-chloro-4-isopropylamino-6-amino-s-triazine (CIAT), hexazinone, metalaxyl, metolachlor, prometryn, prometon, simazine, azithromycin, oxytetracycline, sulfamethoxazole, trimethoprim, and tylosin, had measurable concentrations above their laboratory reporting levels. Concentrations were estimated for an additional 19 compounds that were detected below their laboratory reporting levels. The two most frequently detected compounds were the pesticides atrazine (19 of 20 samples) and simazine (13 of 20 samples). Tylosin, a veterinary antibiotic, was detected in 8 of 20 samples. Other compounds frequently detected at very low concentrations included CIAT and hexazinone (a degradate of atrazine and a pesticide, respectively); camphor (derived from personal-care products or flavorants), para-cresol (various uses including solvent, wood preservative, and in household cleaning products), and N,N-diethyl-m-toluamide (DEET, an insect repellent).

Oblinger, Carolyn J.; Gill, Amy C.; McPherson, Ann K.; Meyer, Michael T.; Furlong, Edward T.

2007-01-01

6

Data on dissolved pesticides and volatile organic compounds in surface and ground waters in the San Joaquin-Tulare basins, California, water years 1992-1995  

USGS Publications Warehouse

This report contains pesticide, volatile organic compound, major ion, nutrient, tritium, stable isotope, organic carbon, and trace-metal data collected from 149 ground-water wells, and pesticide data collected from 39 surface-water stream sites in the San Joaquin Valley of California. Included with the ground-water data are field measurements of pH, specific conductance, alkalinity, temperature, and dissolved oxygen. This report describes data collection procedures, analytical methods, quality assurance, and quality controls used by the National Water-Quality Assessment Program to ensure data reliability. Data contained in this report were collected during a four year period by the San Joaquin?Tulare Basins Study Unit of the United States Geological Survey's National Water-Quality Assessment Program. Surface-water-quality data collection began in April 1992, with sampling done three times a week at three sites as part of a pilot study conducted to provide background information for the surface-water-study design. Monthly samples were collected at 10 sites for major ions and nutrients from January 1993 to March 1995. Additional samples were collected at four of these sites, from January to December 1993, to study spatial and temporal variability in dissolved pesticide concentrations. Samples for several synoptic studies were collected from 1993 to 1995. Ground-water-quality data collection was restricted to the eastern alluvial fans subarea of the San Joaquin Valley. Data collection began in 1993 with the sampling of 21 wells in vineyard land-use settings. In 1994, 29 wells were sampled in almond land-use settings and 9 in vineyard land-use settings; an additional 11 wells were sampled along a flow path in the eastern Fresno County vineyard land-use area. Among the 79 wells sampled in 1995, 30 wells were in the corn, alfalfa, and vegetable land-use setting, and 1 well was in the vineyard land-use setting; an additional 20 were flow-path wells. Also sampled in 1995 were 28 wells used for a regional assessment of ground-water quality in the eastern San Joaquin Valley.

Kinsey, Willie B.; Johnson, Mark V.; Gronberg, JoAnn M.

2005-01-01

7

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

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.

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

2000-01-01

8

Interaction of pesticides with natural organic material  

USGS Publications Warehouse

Two examples of the interaction of pesticides with natural organic materials have been investigated. Sodium humate solubilizes DDT in water and humic acid strongly sorbs 2,4,5-T. These two types of interactions are indicative of the types that one would expect when any organic pesticide is applied to a natural soil-water system.

Wershaw, R.L.; Burcar, P.J.; Goldberg, M.C.

1969-01-01

9

Multi-organ Dysfunction Syndrome with Dual Organophosphate Pesticides Poisoning  

PubMed Central

Organophosphate (OP) pesticide self-poisoning is common in developing countries. Poisoning with dual OP compounds is rare. Multi-organ dysfunction after OP poisoning has a high mortality rate. We report the case of a 27-year-old man who developed multi-organ dysfunction syndrome with fatal outcome after intentional ingestion of 50:50 mixture of two OP compounds, dichlorvos and profenofos. PMID:24403738

Mishra, Ajay; Pandya, Himanshu V.; Dave, Nikhil; Mehta, Manan

2013-01-01

10

Measurement and estimated health risks of semivolatile organic compounds (PCBs, PAHs, pesticides, and phthalates) in ambient air at the Hanford Site  

SciTech Connect

Air samples for polychlorinated biphenyls (PCBs), chlorinated pesticides, phthalate plasticizers, and polycyclic aromatic hydrocarbons (PAHs) were collected at three Hanford Site locations (300-Area South Gate, southeast of 200-East Area, and a background location near Rattlesnake Springs). Samples were collected using high-volume air samplers equipped with a glass fiber filter and polyurethane foam plug sampling train. Target compounds were extracted from the sampling trains and analyzed using capillary gas chromatography with either electron capture detection or mass selective detection. Twenty of the 28 PCB congeners analyzed were found above the detection limits, with 8 of the congeners accounting for over 80% of the average PCB concentrations. The average sum of all individual PCB congeners ranged from 500-740 pg/m{sup 3}, with little apparent difference between the sampling locations. Twenty of the 25 pesticides analyzed were found above the detection limits, with endosulfan I, endosulfan II, and methoxychlor having the highest average concentrations. With the exception of the endosulfans, all other average pesticide concentrations were below 100 pg/m{sup 3}. There was little apparent difference between the air concentrations of pesticides measured at each location. Sixteen of the 18 PAHs analyzed were found above the detection limit. Phenanthrene, fluoranthene, pyrene, fluorene, chrysene, benzo(b)fluoranthene, and naphthalene were the only PAHs with average concentrations above 100 pg/m{sup 3}. Overall, the 300 Area had higher average PAH concentrations compared to the 200-East Area and the background location at Rattlesnake Springs; however, the air concentrations at the 300-Area also are influenced by sources on the Hanford Site and from nearby communities.

Patton, G.W.; Cooper, A.T.; Blanton, M.L.; Lefkovitz, L.F.; Gilfoil, T.J.

1997-09-01

11

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

USGS Publications Warehouse

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

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

1998-01-01

12

SIMULTANEOUS SORPTION OF PESTICIDES AND HEAVY METALS BY MONTMORILLONITE MODIFIED WITH NATURAL ORGANIC CATIONS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Contamination of natural ecosystems by inorganic and organic pollutants is of growing concern. For environmental remediation, a strategy to improve the sorption capacity of clay minerals for organic compounds, including pesticides, and for inorganic compounds, such as heavy metals, could be the repl...

13

Pesticides  

SciTech Connect

This review covers the literature on pesticide analysis published or abstracted in the period between December 15, 1984, and December 15, 1986. The major sources of information were the primary abstracting journals Chemical Abstracts and Analytical Abstracts. Journals that were searched directly include the Journal of the Association of Official Analytical Chemists, Journal of Agricultural and Food Chemistry, Bulletin of Environmental Contamination and Toxicology, Analytical Chemistry, and the Journal of Chromatography (including its bibliography issues). The review is devoted mainly to methods for the determination of residues of pesticides and related compounds in a wide variety of samples and the analysis of pesticide standards. Analyses of pesticide formulations are not covered. The attempt was made to choose the most important publications describing methodology, instrumentation, and applications that would be readily available to readers to this Journal. Abstract citations are given for references from the more obscure journals and those not published in English.

Sherma, J.

1987-06-15

14

40 CFR 455.30 - Applicability; description of the metallo-organic pesticide chemicals manufacturing subcategory.  

...description of the metallo-organic pesticide chemicals manufacturing subcategory. 455.30 Section...GUIDELINES AND STANDARDS (CONTINUED) PESTICIDE CHEMICALS Metallo-Organic Pesticide Chemicals Manufacturing Subcategory § 455.30...

2014-07-01

15

Organic Compounds in Carbonaceous Meteorites  

NASA Technical Reports Server (NTRS)

Carbonaceous meteorites are relatively enriched in soluble organic compounds. To date, these compounds provide the only record available to study a range of organic chemical processes in the early Solar System chemistry. The Murchison meteorite is the best-characterized carbonaceous meteorite with respect to organic chemistry. The study of its organic compounds has related principally to aqueous meteorite parent body chemistry and compounds of potential importance for the origin of life. Among the classes of organic compounds found in Murchison are amino acids, amides, carboxylic acids, hydroxy acids, sulfonic acids, phosphonic acids, purines and pyrimidines (Table 1). Compounds such as these were quite likely delivered to the early Earth in asteroids and comets. Until now, polyhydroxylated compounds (polyols), including sugars (polyhydroxy aldehydes or ketones), sugar alcohols, sugar acids, etc., had not been identified in Murchison. Ribose and deoxyribose, five-carbon sugars, are central to the role of contemporary nucleic acids, DNA and RNA. Glycerol, a three-carbon sugar alcohol, is a constituent of all known biological membranes. Due to the relative lability of sugars, some researchers have questioned the lifetime of sugars under the presumed conditions on the early Earth and postulated other (more stable) compounds as constituents of the first replicating molecules. The identification of potential sources and/or formation mechanisms of pre-biotic polyols would add to the understanding of what organic compounds were available, and for what length of time, on the ancient Earth.

Cooper, Grorge

2001-01-01

16

Identification and measurement of chlorinated organic pesticides in water by electron-capture gas chromatography  

USGS Publications Warehouse

Pesticides, in minute quantities, may affect the regimen of streams, and because they may concentrate in sediments, aquatic organisms, and edible aquatic foods, their detection and their measurement in the parts-per-trillion range are considered essential. In 1964 the U.S. Geological Survey at Menlo Park, Calif., began research on methods for monitoring pesticides in water. Two systems were selected--electron-capture gas chromatography and microcoulometric-titration gas chromatography. Studies on these systems are now in progress. This report provides current information on the development and application of an electron-capture gas chromatographic procedure. This method is a convenient and extremely sensitive procedure for the detection and measurement of organic pesticides having high electron affinities, notably the chlorinated organic pesticides. The electron-affinity detector is extremely sensitive to these substances but it is not as sensitive to many other compounds. By this method, the chlorinated organic pesticide may be determined on a sample of convenient size in concentrations as low as the parts-per-trillion range. To insure greater accuracy in the identifications, the pesticides reported were separated and identified by their retention times on two different types of gas chromatographic columns.

Lamar, William L.; Goerlitz, Donald F.; Law, LeRoy M.

1965-01-01

17

Xenobiotic organic compounds in runoff from fields irrigated with treated wastewater.  

PubMed

Investigations of agricultural nonpoint source pollution typically focus on a relatively narrow range of targeted toxic and biostimulatory compounds (e.g., specific pesticides, nutrients). Regular application of numerous other organic compounds to agricultural fields in pesticide formulations, irrigation water, soil amendments, and fertilizers may result in their transport into surface waters via runoff. We examined whether potentially toxic dissolved and particle-associated "nontarget" organic compounds were present in surface runoff from agricultural fields irrigated with disinfected tertiary recycled water or wastewater effluent-dominated streamwater. Gas chromatographic-mass spectrometric analyses of filtered runoff samples revealed the presence of numerous nontarget compounds of potential toxicological significance including pesticide transformation products, pesticide adjuvant chemicals, plasticizers, flame retardants, pharmaceuticals, and personal care product ingredients. Although the toxicity of many of these compounds is poorly characterized, some may elicit subtle but profound toxicological effects. Agricultural runoff also represented a source of allochthonous natural organic matter to the stream system. PMID:12590482

Pedersen, Joel A; Yeager, Matt A; Suffet, I H

2003-02-26

18

Choosing Organic Pesticides over Synthetic Pesticides May Not Effectively Mitigate Environmental Risk in Soybeans  

PubMed Central

Background Selection of pesticides with small ecological footprints is a key factor in developing sustainable agricultural systems. Policy guiding the selection of pesticides often emphasizes natural products and organic-certified pesticides to increase sustainability, because of the prevailing public opinion that natural products are uniformly safer, and thus more environmentally friendly, than synthetic chemicals. Methodology/Principal Findings We report the results of a study examining the environmental impact of several new synthetic and certified organic insecticides under consideration as reduced-risk insecticides for soybean aphid (Aphis glycines) control, using established and novel methodologies to directly quantify pesticide impact in terms of biocontrol services. We found that in addition to reduced efficacy against aphids compared to novel synthetic insecticides, organic approved insecticides had a similar or even greater negative impact on several natural enemy species in lab studies, were more detrimental to biological control organisms in field experiments, and had higher Environmental Impact Quotients at field use rates. Conclusions/Significance These data bring into caution the widely held assumption that organic pesticides are more environmentally benign than synthetic ones. All pesticides must be evaluated using an empirically-based risk assessment, because generalizations based on chemical origin do not hold true in all cases. PMID:20582315

Bahlai, Christine A.; Xue, Yingen; McCreary, Cara M.; Schaafsma, Arthur W.; Hallett, Rebecca H.

2010-01-01

19

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

USGS Publications Warehouse

One of the most frequently detected organic chemicals in a nationwide study concerning the effects of wastewater on stream water quality conducted in the year 2000 was the widely used insect repellant N,N-diethyl-m-toluamide (DEET). It was detected at levels of 0.02 ??g/L or greater in 73% of the stream sites sampled, with the selection of sampling sites being biased toward streams thought to be subject to wastewater contamination (i.e., downstream from intense urbanization and livestock production). Although DEET frequently was detected at all sites, the median concentration was low (0.05 ??g/L). The highest concentrations of DEET were found in streams from the urban areas (maximum concentration, 1.1 ??g/L). The results of the present study suggest that the movement of DEET to streams through wastewater-treatment systems is an important mechanism that might lead to the exposure of aquatic organisms to this chemical. ?? 2005 SETAC.

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

2005-01-01

20

PERSISTENT PERFLUORINATED ORGANIC COMPOUNDS  

EPA Science Inventory

Perfluorinated compounds (PFCs) have gained notoriety in the recent past. Global distribution of PFCs in wildlife, environmental samples and humans has sparked a recent increase in new investigations concerning PFCs. Historically PFCs have been used in a wide variety of consume...

21

Organic Compounds in Stardust  

NASA Technical Reports Server (NTRS)

The successful return of the STARDUST spacecraft provides a unique opportunity to investigate the nature and distribution of organic matter in cometary dust particles collected from Comet 81P/Wild-2. Analysis of individual cometary impact tracks in silica aerogel using the technique of two-step laser mass spectrometry (L2MS) demonstrates the presence of complex aromatic organic matter. While concerns remain as to the organic purity of the aerogel collection medium and the thermal effects associated with hypervelocity capture, the majority of the observed organic species appear indigenous to the impacting particles and are hence of cometary origin. While the aromatic fraction of the total organic matter present is believed to be small, it is notable in that it appears to be N-rich. Spectral analysis in combination with instrumental detection sensitivities suggest that N is incorporated predominantly in the form of aromatic nitriles (R-C N). While organic species in the STARDUST samples do share some similarities with those present in the matrices of carbonaceous chondrites, the closest match is found with stratospherically collected interplanetary dust particles. These findings are consistent with the notion that a fraction of interplanetary dust is of cometary origin. The presence of complex organic N-containing species in comets has astrobiological implications since comets are likely to have contributed to the prebiotic chemical inventory of both the Earth and Mars.

McKay, David S.; Clemett. Simon J.; Sandford, Scott A.; Nakamura-Messenger, Keiko; Hoerz, Fredrich

2011-01-01

22

Photochemical dimerization of organic compounds  

DOEpatents

At least one of selectivity and reaction rate of photosensitized vapor phase dimerizations, including dehydrodimerizations, hydrodimerizations and cross-dimerizations of saturated and unsaturated organic compounds is improved by conducting the dimerization in the presence of hydrogen or nitrous oxide.

Crabtree, Robert H. (Bethany, CT); Brown, Stephen H. (Princeton, NJ); Muedas, Cesar A. (New Haven, CT); Ferguson, Richard R. (Branford, CT)

1992-01-01

23

Semivolatile organic compounds in indoor environments  

NASA Astrophysics Data System (ADS)

Semivolatile organic compounds (SVOCs) are ubiquitous in indoor environments, redistributing from their original sources to all indoor surfaces. Exposures resulting from their indoor presence contribute to detectable body burdens of diverse SVOCs, including pesticides, plasticizers, and flame retardants. This paper critically examines equilibrium partitioning of SVOCs among indoor compartments. It proceeds to evaluate kinetic constraints on sorptive partitioning to organic matter on fixed surfaces and airborne particles. Analyses indicate that equilibrium partitioning is achieved faster for particles than for typical indoor surfaces; indeed, for a strongly sorbing SVOC and a thick sorptive reservoir, equilibrium partitioning is never achieved. Mass-balance considerations are used to develop physical-science-based models that connect source- and sink-rates to airborne concentrations for commonly encountered situations, such as the application of a pesticide or the emission of a plasticizer or flame retardant from its host material. Calculations suggest that many SVOCs have long indoor persistence, even after the primary source is removed. If the only removal mechanism is ventilation, moderately sorbing compounds ( Koa > 10 10) may persist indoors for hundreds to thousands of hours, while strongly sorbing compounds ( Koa > 10 12) may persist for years. The paper concludes by applying the newly developed framework to explore exposure pathways of building occupants to indoor SVOCs. Accumulation of SVOCs as a consequence of direct air-to-human transport is shown to be potentially large, with a maximum indoor-air processing rate of 10-20 m 3/h for SVOC uptake by human skin, hair and clothing. Levels on human skin calculated with a simple model of direct air-to-skin transfer agree remarkably well with levels measured in dermal hand wipes for SVOCs possessing a wide range of octanol-air partition coefficients.

Weschler, Charles J.; Nazaroff, William W.

24

Extraterrestrial Organic Compounds in Meteorites  

NASA Technical Reports Server (NTRS)

Many organic compounds or their precursors found in meteorites originated in the interstellar or circumstellar medium and were later incorporated into planetesimals during the formation of the solar system. There they either survived intact or underwent further processing to synthesize secondary products on the meteorite parent body. The most distinct feature of CI and CM carbonaceous chondrites, two types of stony meteorites, is their high carbon content (up to 3% of weight), either in the form of carbonates or of organic compounds. The bulk of the organic carbon consists of an insoluble macromolecular material with a complex structure. Also present is a soluble organic fraction, which has been analyzed by several separation and analytical procedures. Low detection limits can be achieved by derivatization of the organic molecules with reagents that allow for analysis by gas chromatography/mass spectroscopy and high performance liquid chromatography. The CM meteorite Murchison has been found to contain more than 70 extraterrestrial amino acids and several other classes of compounds including carboxylic acids, hydroxy carboxylic acids, sulphonic and phosphonic acids, aliphatic, aromatic and polar hydrocarbons, fullerenes, heterocycles as well as carbonyl compounds, alcohols, amines and amides. The organic matter was found to be enriched in deuterium, and distinct organic compounds show isotopic enrichments of carbon and nitrogen relative to terrestrial matter.

Botta, Oliver; Bada, Jeffrey L.; Meyer, Michael (Technical Monitor)

2003-01-01

25

Biomedical Compounds from Marine organisms  

PubMed Central

The Ocean, which is called the ‘mother of origin of life’, is also the source of structurally unique natural products that are mainly accumulated in living organisms. Several of these compounds show pharmacological activities and are helpful for the invention and discovery of bioactive compounds, primarily for deadly diseases like cancer, acquired immuno-deficiency syndrome (AIDS), arthritis, etc., while other compounds have been developed as analgesics or to treat inflammation, etc. The life-saving drugs are mainly found abundantly in microorganisms, algae and invertebrates, while they are scarce in vertebrates. Modern technologies have opened vast areas of research for the extraction of biomedical compounds from oceans and seas.

Jha, Rajeev Kumar; Zi-rong, Xu

2004-01-01

26

Extraterrestrial Organic Compounds in Meteorites  

Microsoft Academic Search

Many organic compounds or their precursorsfound in meteorites originated in the interstellar or circumstellarmedium and were later incorporated intoplanetesimals during the formation of thesolar system. There they either survivedintact or underwent further processing tosynthesize secondary products on themeteorite parent body.The most distinct feature of CI and CM carbonaceouschondrites, two typesof stony meteorites, is their high carbon content(up to 3% of

OLIVER BOTTAand; Jeffrey L. Bada

2002-01-01

27

Extraterrestrial Organic Compounds in Meteorites  

NASA Astrophysics Data System (ADS)

Many organic compounds or their precursorsfound in meteorites originated in the interstellar or circumstellarmedium and were later incorporated intoplanetesimals during the formation of thesolar system. There they either survivedintact or underwent further processing tosynthesize secondary products on themeteorite parent body.The most distinct feature of CI and CM carbonaceouschondrites, two typesof stony meteorites, is their high carbon content(up to 3% of weight), either in theform of carbonates or of organic compounds. The bulkof the organic carbon consistsof an insoluble macromolecular material with a complexstructure. Also present is asoluble organic fraction, which has been analyzedby several separation and analyticalprocedures. Low detection limits can be achievedby derivatization of the organicmolecules with reagents that allow for analysisby gas chromatography/massspectroscopy and high performance liquidchromatography. The CM meteoriteMurchison has been found to contain more than70 extraterrestrial amino acids andseveral other classes of compounds includingcarboxylic acids, hydroxy carboxylicacids, sulphonic and phosphonic acids, aliphatic,aromatic and polar hydrocarbons,fullerenes, heterocycles as well as carbonylcompounds, alcohols, amines and amides.The organic matter was found to be enriched indeuterium, and distinct organiccompounds show isotopic enrichments of carbon andnitrogen relative to terrestrialmatter.

Botta, Oliver; Bada, Jeffrey L.

28

Volatile Organic Compounds in Uremia  

PubMed Central

Background Although “uremic fetor” has long been felt to be diagnostic of renal failure, the compounds exhaled in uremia remain largely unknown so far. The present work investigates whether breath analysis by ion mobility spectrometry can be used for the identification of volatile organic compounds retained in uremia. Methods Breath analysis was performed in 28 adults with an eGFR ?60 ml/min per 1.73 m2, 26 adults with chronic renal failure corresponding to an eGFR of 10–59 ml/min per 1.73 m2, and 28 adults with end-stage renal disease (ESRD) before and after a hemodialysis session. Breath analysis was performed by ion mobility spectrometryafter gas-chromatographic preseparation. Identification of the compounds of interest was performed by thermal desorption gas chromatography/mass spectrometry. Results Breath analyses revealed significant differences in the spectra of patients with and without renal failure. Thirteen compounds were chosen for further evaluation. Some compounds including hydroxyacetone, 3-hydroxy-2-butanone and ammonia accumulated with decreasing renal function and were eliminated by dialysis. The concentrations of these compounds allowed a significant differentiation between healthy, chronic renal failure with an eGFR of 10–59 ml/min, and ESRD (p<0.05 each). Other compounds including 4-heptanal, 4-heptanone, and 2-heptanone preferentially or exclusively occurred in patients undergoing hemodialysis. Conclusion Impairment of renal function induces a characteristic fingerprint of volatile compounds in the breath. The technique of ion mobility spectrometry can be used for the identification of lipophilic uremic retention molecules. PMID:23049998

Seifert, Luzia; Slodzinski, Rafael; Jankowski, Joachim; Zidek, Walter; Westhoff, Timm H.

2012-01-01

29

Pesticides.  

ERIC Educational Resources Information Center

This review is devoted to methods for the determination of residues of pesticides and some related industrial chemicals. Topics include: residue methods, sampling, chromatography, organochlorine pesticides, organophosphorus pesticides, carbamate insecticides, herbicides, fungicides, pyrethrins, fumigants, and related chemicals. (MVL)

Sherma, Joseph

1989-01-01

30

Pesticides  

MedlinePLUS

... pesticides are applied during farming and how much pesticide residue can remain in foods sold in stores. Exposure ... Parents who handle or are otherwise exposed to pesticides at work ... any residue from their skin, and removing their clothes and ...

31

40 CFR Table 2 to Part 455 - Organic Pesticide Active Ingredient Effluent Limitations Best Available Technology Economically...  

Code of Federal Regulations, 2010 CFR

... 2010-07-01 false Organic Pesticide Active Ingredient Effluent Limitations...EFFLUENT GUIDELINES AND STANDARDS PESTICIDE CHEMICALS Pt. 455, Table 2 Table 2 to Part 455—Organic Pesticide Active Ingredient Effluent...

2010-07-01

32

40 CFR Table 2 to Part 455 - Organic Pesticide Active Ingredient Effluent Limitations Best Available Technology Economically...  

Code of Federal Regulations, 2011 CFR

... 2011-07-01 false Organic Pesticide Active Ingredient Effluent Limitations...EFFLUENT GUIDELINES AND STANDARDS PESTICIDE CHEMICALS Pt. 455, Table 2 Table 2 to Part 455—Organic Pesticide Active Ingredient Effluent...

2011-07-01

33

40 CFR Table 3 to Part 455 - Organic Pesticide Active Ingredient New Source Performance Standards (NSPS) and Pretreatment...  

Code of Federal Regulations, 2011 CFR

... 2011-07-01 false Organic Pesticide Active Ingredient New Source Performance...EFFLUENT GUIDELINES AND STANDARDS PESTICIDE CHEMICALS Pt. 455, Table 3 Table 3 to Part 455—Organic Pesticide Active Ingredient New Source...

2011-07-01

34

Efficiency of conventional drinking-water-treatment processes in removal of pharmaceuticals and other organic compounds  

Microsoft Academic Search

Samples of water and sediment from a conventional drinking-water-treatment (DWT) plant were analyzed for 113 organic compounds (OCs) that included pharmaceuticals, detergent degradates, flame retardants and plasticizers, polycyclic aromatic hydrocarbons (PAHs), fragrances and flavorants, pesticides and an insect repellent, and plant and animal steroids. 45 of these compounds were detected in samples of source water and 34 were detected in

Paul E. Stackelberg; Jacob Gibs; Edward T. Furlong; Michael T. Meyer; Steven D. Zaugg; R. Lee Lippincott

2007-01-01

35

AUTOMATED ANALYSIS OF AQUEOUS SAMPLES CONTAINING PESTICIDES, ACIDIC/BASIC/NEUTRAL SEMIVOLATILES AND VOLATILE ORGANIC COMPOUNDS BY SOLID PHASE EXTRACTION COUPLED IN-LINE TO LARGE VOLUME INJECTION GC/MS  

EPA Science Inventory

Data is presented on the development of a new automated system combining solid phase extraction (SPE) with GC/MS spectrometry for the single-run analysis of water samples containing a broad range of organic compounds. The system uses commercially available automated in-line 10-m...

36

Pesticides  

MedlinePLUS

... or cause harm to crops, people, or animals. Pesticides can help get rid of them. Pesticides are not just insect killers. They also include ... mildew, germs, and more. Many household products contain pesticides. Pesticides can protect your health by killing germs, ...

37

Volatile organic compound sensing devices  

DOEpatents

Apparatus employing vapochromic materials in the form of inorganic double complex salts which change color reversibly when exposed to volatile organic compound (VOC) vapors is adapted for VOC vapor detection, VOC aqueous matrix detection, and selective VOC vapor detection. The basic VOC vapochromic sensor is incorporated in various devices such as a ground probe sensor, a wristband sensor, a periodic sampling monitor, a soil/water penetrometer, an evaporative purge sensor, and various vacuum-based sensors which are particularly adapted for reversible/reusable detection, remote detection, continuous monitoring, or rapid screening of environmental remediation and waste management sites. The vapochromic sensor is used in combination with various fiber optic arrangements to provide a calibrated qualitative and/or quantitative indication of the presence of VOCs. 15 figs.

Lancaster, G.D.; Moore, G.A.; Stone, M.L.; Reagen, W.K.

1995-08-29

38

Volatile organic compound sensing devices  

DOEpatents

Apparatus employing vapochromic materials in the form of inorganic double complex salts which change color reversibly when exposed to volatile organic compound (VOC) vapors is adapted for VOC vapor detection, VOC aqueous matrix detection, and selective VOC vapor detection. The basic VOC vapochromic sensor is incorporated in various devices such as a ground probe sensor, a wristband sensor, a periodic sampling monitor, a soil/water penetrometer, an evaporative purge sensor, and various vacuum-based sensors which are particularly adapted for reversible/reusable detection, remote detection, continuous monitoring, or rapid screening of environmental remediation and waste management sites. The vapochromic sensor is used in combination with various fiber optic arrangements to provide a calibrated qualitative and/or quantitative indication of the presence of VOCs.

Lancaster, Gregory D. (Idaho Falls, ID); Moore, Glenn A. (Idaho Falls, ID); Stone, Mark L. (Idaho Falls, ID); Reagen, William K. (Stillwater, MN)

1995-01-01

39

Determination of organic compounds in bottled waters  

Microsoft Academic Search

The presence of organic compounds in bottled waters available in the Greek market and their fate when the representative samples exposed at different conditions were the main purposes of this study. The determination of the organic compounds was performed by gas chromatography–mass spectrometry techniques. Disinfection by-products compounds, such as trihalomethanes (THMs) and haloacetic acids (HAAs), were detected at low concentrations

Stavroula V. Leivadara; Anastasia D. Nikolaou; Themistokles D. Lekkas

2008-01-01

40

Chlorobenzenes, chlorinated pesticides, coplanar chlorobiphenyls and other organochlorine compounds in Greenland biota  

Microsoft Academic Search

This paper summarises the levels and composition of chlorobenzenes, chlorinated pesticides, coplanar polychlorinated biphenyls (PCBs) and the chlorinated compounds octachlorostyrene (OCS), hexachlorocyclobutadiene (HCBD) and pentachloro-anisole (PCA) in biota from the terrestrial, freshwater and marine environment of Greenland. The data were obtained during the second phase of the Arctic Monitoring and Assessment Programme (AMAP). Of the chlorobenzenes, hexachlorobenzene was the main

Katrin Vorkamp; Frank Riget; Marianne Glasius; Maria Pécseli; Michel Lebeuf; Derek Muir

2004-01-01

41

40 CFR Table 1 to Part 455 - List of Organic Pesticide Active Ingredients  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false List of Organic Pesticide Active Ingredients...Table 1 to Part 455—List of Organic Pesticide Active Ingredients...3,6-Trichlorophenylacetic acid] 00085-34-7 14 ...5-Trichlorophenoxyacetic acid] 00093-76-5 15...

2011-07-01

42

SORPTION OF HYDROPHOBIC ORGANIC COMPOUNDS BY SEDIMENTS  

EPA Science Inventory

Thermodynamic and kinetic principles which govern the uptake of nonionic, hydrophobic organic chemicals by sediments in aqueous systems are summarized. Sorption onto organic-rich sediments can be modeled as a process where the hydrophobic compound partitions into the organic matt...

43

A Reconnaissance of selected organic compounds in streams in tribal lands in Central Oklahoma, January-February 2009  

USGS Publications Warehouse

The U.S. Geological Survey worked in cooperation with the U.S. Environmental Protection Agency and the Kickapoo Tribe of Oklahoma on two separate reconnaissance projects carried out concurrently. Both projects entailed the use of passive samplers as a sampling methodology to investigate the detection of selected organic compounds at stream sites in jurisdictional areas of several tribes in central Oklahoma during January-February 2009. The focus of the project with the U.S. Environmental Protection Agency was the detection of pesticides and pesticide metabolites using Semipermeable Membrane Devices at five stream sites in jurisdictional areas of several tribes. The project with the Kickapoo Tribe of Oklahoma focused on the detection of pesticides, pesticide metabolites, polycyclic aromatic hydrocarbons, polychlorinated biphenyl compounds, and synthetic organic compounds using Semipermeable Membrane Devices and Polar Organic Chemical Integrative Samplers at two stream sites adjacent to the Kickapoo tribal lands. The seven stream sites were located in central Oklahoma on the Cimarron River, Little River, North Canadian River, Deep Fork, and Washita River. Extracts from SPMDs submerged at five stream sites, in cooperation with the U.S. Environmental Protection Agency, were analyzed for 46 pesticides and 6 pesticide metabolites. Dacthal, a pre-emergent herbicide, was detected at all five sites. Pendimethalin, also a pre-emergent, was detected at one site. The insecticides chlorpyrifos and dieldrin were detected at three sites and p,p'-DDE, a metabolite of the insecticide DDT, also was detected at three sites. SPMDs and POCIS were submerged at the upstream edge and downstream edge of the Kickapoo tribal boundaries. Both sites are downstream from the Oklahoma City metropolitan area and multiple municipal wastewater treatment plants. Extracts from the passive samplers were analyzed for 62 pesticides, 10 pesticide metabolites, 3 polychlorinated biphenyl compounds, 35 polycyclic aromatic hydrocarbons, and 49 synthetic organic compounds. Ten pesticides and four pesticide metabolites were detected at the upstream site and seven pesticides and four pesticide metabolites were detected at the downstream site. Pesticides detected at both sites were atrazine, chlorpyrifos, dacthal, dieldrin, metolachlor, pendimethalin, and trans-nonachlor. Additionally at the upstream site, heptachlor, pentachlorophenol, and prometon were detected. The pesticide metabolites p,p'-DDE, cis-chlordane, and trans-chlordane also were detected at both sites. Polychlorinated biphenyl compounds aroclor-1016/1242, aroclor-1254, and aroclor-1260 were detected at both sites. The upstream site had 16 polycyclic aromatic hydrocarbon detections and the downstream site had 8 detections. Because of chromatographic interference during analysis, a positive identification of 17 polycyclic aromatic hydrocarbons could not be made. Consequently, there may have been a greater number of these compounds detected at both sites. A total of 36 synthetic organic compounds were detected at the two sites adjacent to the Kickapoo tribal lands. The upstream site had 21 synthetic organic compound detections: three detergent metabolites, two fecal indicators, three flame retardants, seven industrial compounds, five compounds related to personal care products, and beta-sitosterol, a plant sterol. Fifteen synthetic organic compounds were detected at the downstream site and included: one fecal indicator, three flame retardants, six industrial compounds, and five compounds related to personal care products.

Becker, Carol J.

2010-01-01

44

Characterization of polar organic compounds in the organic film on indoor and outdoor glass windows.  

PubMed

Organic films on an impervious surface (window glass) were sampled at paired indoor-outdoor sites in July 2000 and characterized for their paraffinic and polar organic compositions along an urban-rural transect. Four classes of polar compounds (C11-C31 aliphatic monocarboxylic, C6-C14 dicarboxylic, nine aromatic polycarboxylic, and five terpenoid acids) constituted between 81 and 95% (w/w) of the total organic fraction analyzed comprising n-alkanes (C10-C36), 46 PAH, 97 PCBs, and 18 OC pesticides. Concentrations of the polar compounds plus their precursors, n-alkanes, ranged from 8 to 124 microg m(-20 and were dominated by monocarboxylic acids (67-89%, w/w). On outdoor windows, n-alkanes, aromatic acids, and terpenoid acids decreased in concentration along the urban-rural transect. The carbon preference index values and the interpretations of individual compounds indicate that the main sources of n-alkanes were plant waxes followed by petrogenic sources; monocarboxylic and dicarboxylic acids were from plant waxes and animal fats. Results of principal component analysis showed closer correspondence between outdoor and indoor signatures than among locations. In outdoor films, these compounds are suggested to play an important role in mediating chemical fate in urban areas by air-film exchange and facilitating "wash-off" due to their surfactant-like properties. In indoor films, these compounds provide a medium for the accumulation of more toxic compounds. PMID:12831015

Liu, Qin-Tao; Chen, Rachel; McCarry, Brian E; Diamond, Miriam L; Bahavar, Bagher

2003-06-01

45

Methods for the determination of organic compounds in drinking water  

SciTech Connect

Thirteen analytical methods for the identification and measurement of organic compounds in drinking water are described in detail. Six of the methods are for volatile organic compounds (VOCs) and certain disinfection by-products. These methods were cited in the Federal Register of July 8, 1987, under the National Primary Drinking Water Regulations. The other seven methods are designed for the determination of a variety of synthetic organic compounds and pesticides, and these methods were cited in proposed drinking-water regulations in the Federal Register of May 22, 1989. Five of the methods utilize the inert gas purge-and-trap extraction procedure for VOCs, six methods employ a classical liquid-liquid extraction, one method uses a new liquid-solid extraction technique, and one method is for direct aqueous analysis. Of the 13 methods, 12 use either packed or capillary gas-chromatography column separations followed by detection with mass spectrometry or a selective gas-chromatography detector. One method is based on a high-performance liquid-chromatography separation.

Not Available

1988-12-01

46

Microwave spectra of some volatile organic compounds  

NASA Technical Reports Server (NTRS)

A computer-controlled microwave (MRR) spectrometer was used to catalog reference spectra for chemical analysis. Tables of absorption frequency, peak absorption intensity, and integrated intensity are included for 26 volatile organic compounds, all but one of which contain oxygen.

White, W. F.

1975-01-01

47

Alkylation of organic aromatic compounds  

DOEpatents

Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C[sub 2] to C[sub 10] olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80 C to 500 C, using as the catalyst a molecular sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene to about the mid point of the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms. 1 figures.

Smith, L.A. Jr.; Arganbright, R.P.; Hearn, D.

1993-09-07

48

Alkylation of organic aromatic compounds  

DOEpatents

Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C[sub 2] to C[sub 10] olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80 C to 500 C, using as the catalyst a molecular sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene below the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms. 1 fig.

Smith, L.A. Jr.; Arganbright, R.P.; Hearn, D.

1994-06-14

49

Alkylation of organic aromatic compounds  

DOEpatents

Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C.sub.2 to C.sub.10 olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80.degree. C. to 500.degree. C., using as the catalyst a mole sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene below the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms.

Smith, Jr., Lawrence A. (Houston, TX)

1989-01-01

50

Alkylation of organic aromatic compounds  

DOEpatents

Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C[sub 2] to C[sub 10] olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80 C to 500 C, using as the catalyst a mole sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene below the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms. 1 fig.

Smith, L.A. Jr.

1989-07-18

51

Alkylation of organic aromatic compounds  

DOEpatents

Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C.sub.2 to C.sub.10 olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80.degree. C. to 500.degree. C., using as the catalyst a mole sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene to about the mid point of the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms.

Smith, Jr., Lawrence A. (Bellaire, TX); Arganbright, Robert P. (Seabrook, TX); Hearn, Dennis (Houston, TX)

1993-01-01

52

Alkylation of organic aromatic compounds  

DOEpatents

Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C.sub.2 to C.sub.10 olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80.degree. C. to 500.degree. C., using as the catalyst a mole sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene below the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms.

Smith, Jr., Lawrence A. (Bellaire, TX); Arganbright, Robert P. (Seabrook, TX); Hearn, Dennis (Houston, TX)

1994-01-01

53

Clean process to destroy arsenic-containing organic compounds with recovery of arsenic  

DOEpatents

A reduction method is provided for the treatment of arsenic-containing organic compounds with simultaneous recovery of pure arsenic. Arsenic-containing organic compounds include pesticides, herbicides, and chemical warfare agents such as Lewisite. The arsenic-containing compound is decomposed using a reducing agent. Arsine gas may be formed directly by using a hydrogen-rich reducing agent, or a metal arsenide may be formed using a pure metal reducing agent. In the latter case, the arsenide is reacted with an acid to form arsine gas. In either case, the arsine gas is then reduced to elemental arsenic. 1 fig.

Upadhye, R.S.; Wang, F.T.

1996-08-13

54

Clean process to destroy arsenic-containing organic compounds with recovery of arsenic  

DOEpatents

A reduction method is provided for the treatment of arsenic-containing organic compounds with simultaneous recovery of pure arsenic. Arsenic-containing organic compounds include pesticides, herbicides, and chemical warfare agents such as Lewisite. The arsenic-containing compound is decomposed using a reducing agent. Arsine gas may be formed directly by using a hydrogen-rich reducing agent, or a metal arsenide may be formed using a pure metal reducing agent. In the latter case, the arsenide is reacted with an acid to form arsine gas. In either case, the arsine gas is then reduced to elemental arsenic.

Upadhye, Ravindra S. (Pleasanton, CA); Wang, Francis T. (Danville, CA)

1996-01-01

55

(CHINA) PERFLUORINATED ORGANIC COMPOUND EXPOSURE ASSESSMENT RESEARCH  

EPA Science Inventory

A wide range of perfluorinated organic compounds (PFCs) has been used in a variety of industrial processes and consumer products. The most commonly studied PFCs include perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), but there are many more compounds in this c...

56

PERFLUORINATED ORGANIC COMPOUND EXPOSURE ASSESSMENT RESEARCH  

EPA Science Inventory

A wide range of perfluorinated organic compounds (PFCs) has been used in a variety of industrial processes and consumer products. The most commonly studied PFCs include perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), but there are many more compounds in this c...

57

VOLATILE ORGANIC COMPOUNDS (VOCS) CHAPTER 31.  

EPA Science Inventory

The term "volatile organic compounds' (VOCs) was originally coined to refer, as a class, to carbon-containing chemicals that participate in photochemical reactions in the ambient (outdoor) are. The regulatory definition of VOCs used by the U.S. EPA is: Any compound of carbon, ex...

58

Volatile organic compounds of Schenella pityophilus.  

PubMed

Volatile organic compounds of Schenella pityophilus have been identified via solid-phase microextraction-gas chromatography-mass spectrometry analysis. Ten compounds have been identified, in which 3-methylthio-1-propene was the most significant component. Some other components were previously identified in Tuber aestivum and Tuber melanosporum. PMID:22236093

D'Auria, Maurizio; Racioppi, Rocco; Rana, Gian Luigi

2013-01-01

59

Organic compounds passage through RO membranes  

Microsoft Academic Search

Organic solute permeation, sorption, and rejection by reverse osmosis membranes, from aqueous solutions, were studied experimentally and via artificial neural networks (ANN)-based quantitative structure–property relations (QSPR), for a set of fifty organic compounds for polyamide and cellulose acetate membranes. Membrane solute sorption and passage for dead-end filtration model experiments were quantified based on radioactivity measurements for radiolabeled compounds in the

Dan Libotean; Jaume Giralt; Robert Rallo; Yoram Cohen; Francesc Giralt; Harry F. Ridgway; Grisel Rodriguez; Don Phipps

2008-01-01

60

EXPOSURE OF AMPHIBIANS TO SEMI-VOLATILE ORGANIC COMPOUNDS IN THE SIERRA NEVADA MOUNTAINS AND CALIFORNIA CASCADES: RELATIONSHIP BETWEEN TADPOLE TISSUE AND SEDIMENT CONCENTRATIONS  

EPA Science Inventory

Pesticides and other semi-volatile organic compounds (SOCs) undergo regional and longrange atmospheric transport. One such example is the transport of current-use pesticides from the intensely cultivated Central Valley of California into the adjacent Sierra Nevada and Cascade Mou...

61

Biogeochemical processes governing exposure and uptake of organic pollutant compounds in aquatic organisms.  

PubMed Central

This paper reviews current knowledge of biogeochemical cycles of pollutant organic chemicals in aquatic ecosystems with a focus on coastal ecosystems. There is a bias toward discussing chemical and geochemical aspects of biogeochemical cycles and an emphasis on hydrophobic organic compounds such as polynuclear aromatic hydrocarbons, polychlorinated biphenyls, and chlorinated organic compounds used as pesticides. The complexity of mixtures of pollutant organic compounds, their various modes of entering ecosystems, and their physical chemical forms are discussed. Important factors that influence bioavailability and disposition (e.g., organism-water partitioning, uptake via food, food web transfer) are reviewed. These factors include solubilities of chemicals; partitioning of chemicals between solid surfaces, colloids, and soluble phases; variables rates of sorption, desorption; and physiological status of organism. It appears that more emphasis on considering food as a source of uptake and bioaccumulation is important in benthic and epibenthic ecosystems when sediment-associated pollutants are a significant source of input to an aquatic ecosystem. Progress with mathematical models for exposure and uptake of contaminant chemicals is discussed briefly. PMID:1904812

Farrington, J W

1991-01-01

62

Alkylation of organic aromatic compounds  

DOEpatents

Aromatic compounds are alkylated in a combination reactor/distillation column comprising a vessel suitable for operating between 70 C and 500 C and from 0.5 to 20 atmospheres pressure; an inert distillation packing in the lower one-third of said vessel; solid acidic catalytic material such as zeolites or an acidic cation exchange resin supported in the middle one-third of said vessel; and inert distillation packing in the upper one-third of said vessel. A benzene inlet is located near the upper end of the vessel; an olefin inlet is juxtaposed with said solid acidic catalytic material; a bottoms outlet is positioned near the bottom of said vessel for removing said cumene and ethyl benzene; and an overhead outlet is placed at the top of said vessel for removing any unreacted benzene and olefin.

Smith, L.A. Jr.; Arganbright, R.P.; Hearn, D.

1993-01-05

63

Alkylation of organic aromatic compounds  

DOEpatents

Aromatic compounds are alkylated in a combination reactor/distillation column comprising a vessel suitable for operating between 70.degree. C. and 500.degree. C. and from 0.5 to 20 atmospheres pressure; an inert distillation packing in the lower one-third of said vessel; solid acidic catalytic material such as zeolites or an acidic cation exchange resin supported in the middle one-third of said vessel; and inert distillation packing in the upper one-third of said vessel. A benzene inlet is located near the upper end of the vessel; an olefin inlet is juxtaposed with said solid acidic catalytic material; a bottoms outlet is positioned near the bottom of said vessel for removing said cumene and ethyl benzene; and an overhead outlet is placed at the top of said vessel for removing any unreacted benzene and olefin.

Smith, Jr., Lawrence A. (Bellaire, TX); Arganbright, Robert P. (Seabrook, TX); Hearn, Dennis (Houston, TX)

1993-01-01

64

Organic mercury compounds and autoimmunity  

Microsoft Academic Search

Based on in vitro studies and short-term in vivo studies, all mercurials were for a long time considered as prototypic immunosuppressive substances. Recent studies have confirmed that organic mercurials such as methyl mercury (MeHg) and ethyl mercury (EtHg) are much more potent immunosuppressors than inorganic mercury (Hg). However, Hg interacts with the immune system in the presence of a susceptible

Said Havarinasab; Per Hultman

2005-01-01

65

Reflectance spectroscopy of organic compounds: 1. Alkanes  

USGS Publications Warehouse

Reflectance spectra of the organic compounds comprising the alkane series are presented from the ultraviolet to midinfrared, 0.35 to 15.5 /??m. Alkanes are hydrocarbon molecules containing only single carbon-carbon bonds, and are found naturally on the Earth and in the atmospheres of the giant planets and Saturn's moon, Titan. This paper presents the spectral properties of the alkanes as the first in a series of papers to build a spectral database of organic compounds for use in remote sensing studies. Applications range from mapping the environment on the Earth, to the search for organic molecules and life in the solar system and throughout the. universe. We show that the spectral reflectance properties of organic compounds are rich, with major diagnostic spectral features throughout the spectral range studied. Little to no spectral change was observed as a function of temperature and only small shifts and changes in the width of absorption bands were observed between liquids and solids, making remote detection of spectral properties throughout the solar system simpler. Some high molecular weight organic compounds contain single-bonded carbon chains and have spectra similar to alkanes even ' when they fall into other families. Small spectral differences are often present allowing discrimination among some compounds, further illustrating the need to catalog spectral properties for accurate remote sensing identification with spectroscopy.

Clark, R.N.; Curchin, J.M.; Hoefen, T.M.; Swayze, G.A.

2009-01-01

66

40 CFR Table 3 to Part 455 - Organic Pesticide Active Ingredient New Source Performance Standards (NSPS) and Pretreatment...  

Code of Federal Regulations, 2010 CFR

...NSPS) and Pretreatment Standards for New Sources (PSNS) 3 Table 3 to Part 455 Protection of Environment ENVIRONMENTAL PROTECTION...GUIDELINES AND STANDARDS PESTICIDE CHEMICALS Pt. 455, Table 3 Table 3 to Part 455—Organic Pesticide Active...

2010-07-01

67

MODIFICATION AND EVALUATION OF A HIGH-VOLUME AIR SAMPLER FOR PESTICIDES AND SEMIVOLATILE INDUSTRIAL ORGANIC CHEMICALS  

EPA Science Inventory

Previously we reported the development and evaluation of a high-volume air sampler for pesticides and other semivolatile industrial organic chemicals (1). This sampler has proved useful for monitoring airborne pesticides associated with agricultural applications (2) and polychlor...

68

Origin of organic compounds in carbonaceous chondrites  

NASA Astrophysics Data System (ADS)

Carbonaceous chondrites, a class of primitive meteorite, have long been known to contain their complement of carbon largely in the form of organic, i.e., hydrocarbon-related, matter. Both discrete organic compounds and an insoluble, macromolecular material are present. Several characteristics of these materials provide evidence for their abiotic origin. The principal formation hypothesis have invoked chemistry occurring either in the solar nebula or on the parent body. However, recent stable isotope analyses of the meteorite carboxylic acids and amino acids indicate that they may be related to interstellar cloud compounds. These results suggest a formation scheme in which interstellar compounds were incorporated into the parent body and subsequently converted to the present suite of meteorite organics by the hydrothermal process believed to have formed the clay minerals of the meteorite matrix.

Cronin, J. R.

69

Catalyst for Oxidation of Volatile Organic Compounds  

NASA Technical Reports Server (NTRS)

Disclosed is a process for oxidizing volatile organic compounds to carbon dioxide and water with the minimal addition of energy. A mixture of the volatile organic compound and an oxidizing agent (e.g. ambient air containing the volatile organic compound) is exposed to a catalyst which includes a noble metal dispersed on a metal oxide which possesses more than one oxidation state. Especially good results are obtained when the noble metal is platinum, and the metal oxide which possesses more than one oxidation state is tin oxide. A promoter (i.e., a small amount of an oxide of a transition series metal) may be used in association with the tin oxide to provide very beneficial results.

Wood, George M. (Inventor); Upchurch, Billy T. (Inventor); Schryer, David R. (Inventor); Davis, Patricia P. (Inventor); Kielin, Erik J. (Inventor); Brown, Kenneth G. (Inventor); Schyryer, Jacqueline L. (Inventor); DAmbrosia, Christine M. (Inventor)

2000-01-01

70

ORGANIC PESTICIDE MODIFICATION OF SPECIES INTERACTIONS USING ANNUAL PLANT COMMUNITIES  

EPA Science Inventory

A method is proposed and tested for assessing multispecies responses to three pesticides (atrazine, 2,4,D and malathion). Pesticides were applied at two concentrations, mon model plant communities grown in raised beds using soil containing a natural weed bank. over by species was...

71

A PILOT STUDY OF CHILDREN'S TOTAL EXPOSURE TO PERSISTENT PESTICIDES AND OTHER PERSISTENT ORGANIC POLLUTANTS (CTEPP)  

EPA Science Inventory

The Pilot Study of Children's Total Exposure to Persistent Pesticides and Other Persistent Organic Pollutants (CTEPP) investigated the aggregate exposures of 257 preschool children and their primary adult caregivers to pollutants commonly detected in their everyday environments. ...

72

Metastable Equilibria Among Aqueous Organic Compounds  

NASA Astrophysics Data System (ADS)

Metastable equilibrium states exist when reactions among a subset of compounds in a chemical system are reversible even though other irreversible reactions exist in the same system. The existence of metastable equilibrium among organic compounds was initially detected by comparing ratios of organic acid concentrations reported for oil-field brines (Shock, 1988, Geology 16, 886-890; Shock, 1989, Geology 17, 572-573), and calculating the same ratios for likely oxidation states determined by mineral assemblages and mixtures of hydrocarbons in coexisting petroleum (Shock, 1994, in: The Role of Organic Acids in Geological Processes, Springer). This led to the notion of extending the concept of metastable equilibrium states to explicitly account for petroleum compositions (Helgeson et al., 1993, GCA, 57, 3295-3339), which eventually yielded the concept of hydrolytic disproportionation of kerogens to produce petroleum and CO2(g) (Helgeson et al., 2009, GCA, 73, 594-695). Experimental tests of metastable equilibrium among organic compounds began with the identification of reversible reactions between alkanes and alkenes that are dependent on the H2 fugacity of the experimental system (Seewald, 1994, Nature 370, 285-287). These were followed with a comprehensive series of long-term experiments leading to the hypothesis that reversible reactions include alkanes, alkenes, alcohol, aldehydes, ketones and carboxylic acids (e.g., Seewald, 2001, GCA 65, 1641-1664; 2003, Nature 426, 327-333; McCollom & Seewald, 2003, GCA 67, 3645-3664). We have conducted sets of hydrothermal organic transformation experiments that test the extent to which these reactions are indeed reversible using aromatic and cyclic compounds. Results demonstrate reversibility for reactions among dibenzyl ketone, 1,3-diphenyl-2-propanol, 1,3-diphenylpropene and 1,3-diphenylpropane, as well as among methylcyclohexanes, methylcyclohexenes, methylcyclohexanols, methylcyclohexanones and methylcyclohexadienes. The compounds chosen for study include structural features that provide mechanistic insight into the reactions. By including cyclic and aromatic compounds, these results expand the diversity of organic compounds that react reversibly in geochemical processes. It follows that metastable equilibria among organic compounds may be inescapable during hydrothermal alteration and petroleum generation.

Shock, E.; Shipp, J.; Yang, Z.; Gould, I. R.

2011-12-01

73

Emerging Control Technologies for Volatile Organic Compounds  

Microsoft Academic Search

Environmental problems associated with volatile organic compounds (VOCs) in the atmosphere have provided the driving force for sustained fundamental and applied research in the area of environmental remediation. Conventional methods currently used to treat VOCs include incineration, condensation, adsorption, and absorption. Incineration and condensation are cost-effective only for moderate to high VOC concentrations. Adsorption and absorption do not destroy VOCs

Geeta Rani Parmar; N. N. Rao

2008-01-01

74

Ozone Production Potential of Volatile Organic Compounds  

Microsoft Academic Search

Calculation of the ozone production potential of Volatile Organic Compounds (VOC) has traditionally been performed using so-called incremental reactivity techniques. Here were present a new approach to this problem using a photochemical box model with a tagged chemical mechanism. The results of our approach are consistent with previous work, but deliver much more detailed information about the VOC intermediate oxidation

T. Butler; M. G. Lawrence; J. Lelieveld

2010-01-01

75

Fate and Transfer of Semivolatile Organic Compounds in a Multi-Compartment Environment  

Microsoft Academic Search

\\u000a Semivolatile organic compounds (SVOCs) comprise many priority pollutants such as polycyclic aromatic hydrocarbons (PAHs),\\u000a organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs). These pollutants can be introduced into the environment\\u000a via the atmosphere, for example, in the emissions of incomplete combustion of fossil fuels (e.g. PAHs), out-gassing from pollutant-containing\\u000a media such as paints, transformers and capacitors etc. (e.g. PCBs) and by

Rajasekhar Balasubramanian; Jun He

76

Levels of selected organic compounds in materials for candle production and human exposure to candle emissions  

Microsoft Academic Search

Polychlorinated dibenzo-p-dioxins (PCDD), dibenzofurans (PCDF) selected chlorinated pesticides, polycyclic aromatic hydrocarbons (PAH) and some volatile organic compounds (VOC) were analysed in the exhaust fumes of candles made from different waxes and finishing materials. To guarantee defined burning conditions a chamber was developed for the sampling of the exhaust fumes. Using a simple exposure model, the inhalative uptake of PCDD\\/PCDF by

C. Lau; H. Fiedler; O. Hutzinger; K.-H. Schwind; J. Hosseinpour

1997-01-01

77

Global Exposure Modelling of Semivolatile Organic Compounds  

NASA Astrophysics Data System (ADS)

Organic compounds which are persistent and toxic as the agrochemicals ?-hexachlorocyclohexane (?-HCH, lindane) and dichlorodiphenyltrichloroethane (DDT) pose a hazard for the ecosystems. These compounds are semivolatile, hence multicompartmental substances and subject to long-range transport (LRT) in atmosphere and ocean. Being lipophilic, they accumulate in exposed organism tissues and biomagnify along food chains. The multicompartmental global fate and LRT of DDT and lindane in the atmosphere and ocean have been studied using application data for 1980, on a decadal scale using a model based on the coupling of atmosphere and (for the first time for these compounds) ocean General Circulation Models (ECHAM5 and MPI-OM). The model system encompasses furthermore 2D terrestrial compartments (soil and vegetation) and sea ice, a fully dynamic atmospheric aerosol (HAM) module and an ocean biogeochemistry module (HAMOCC5). Large mass fractions of the compounds are found in soil. Lindane is also found in comparable amount in ocean. DDT has the longest residence time in almost all compartments. The sea ice compartment locally almost inhibits volatilization from the sea. The air/sea exchange is also affected , up to a reduction of 35 % for DDT by partitioning to the organic phases (suspended and dissolved particulate matter) in the global oceans. Partitioning enhances vertical transport in the sea. Ocean dynamics are found to be more significant for vertical transport than sinking associated with particulate matter. LRT in the global environment is determined by the fast atmospheric circulation. Net meridional transport taking place in the ocean is locally effective mostly via western boundary currents, upon applications at mid- latitudes. The pathways of the long-lived semivolatile organic compounds studied include a sequence of several cycles of volatilisation, transport in the atmosphere, deposition and transport in the ocean (multihopping substances). Multihopping is more significant for DDT than for lindane. It enhances the LRT potential for both compounds.

Guglielmo, F.; Lammel, G.; Maier-Reimer, E.

2008-12-01

78

Nonvolatile organic compounds in treated waters.  

PubMed Central

Over the past decade much information has been published on the analysis of organics extracted from treated water. Certain of these organics have been shown to be by-products of the chlorination disinfection process and to possess harmful effects at high concentrations. This has resulted in increased interest in alternative disinfection processes, particularly ozonation. The data on organics had been largely obtained by using gas chromatography-mass spectrometry, which is only capable of analyzing, at best, 20% of the organics present in treated water. Research in key areas such as mutagenicity testing of water and characterization of chlorination and ozonation by-products has emphasized the need for techniques suitable for analysis of the remaining nonvolatile organics. Several methods for the isolation of nonvolatile organics have been evaluated and, of these, freeze-drying followed by methanol extraction appears the most suitable. Reverse-phase HPLC was used for separation of the methanol extract, but increased resolution for separation of the complex mixtures present is desirable. In this context, high resolution size exclusion chromatography shows promise. Characterization of separated nonvolatiles is possible by the application of state-of-the-art mass spectrometric techniques. Results obtained by these techniques have shown that the nonvolatile organic fraction of chlorinated drinking water consists of many discrete compounds. Among these, some of the chlorinated compounds are almost certainly by-products of disinfection. Studies of the by-products of ozonation of fulvic and humic acids isolated from river waters have indicated a similar proportion of nonvolatile organics. Further, ozonation can result in the release of compounds that are trapped in the macromolecules. PMID:6759110

Watts, C D; Crathorne, B; Fielding, M; Killops, S D

1982-01-01

79

Pesticide safety risk, food chain organization, and the adoption of sustainable farming practices. The case of Moroccan early tomatoes  

E-print Network

1 Pesticide safety risk, food chain organization, and the adoption of sustainable farming practices practices within the greenhouses owned by private packers. Key-words Food safety, pesticides, integrated Fresh produce pesticide safety risk has grown into a major concern of north European consumers

Paris-Sud XI, Université de

80

Organic photosensitive devices using subphthalocyanine compounds  

DOEpatents

An organic photosensitive optoelectronic device, having a donor-acceptor heterojunction of a donor-like material and an acceptor-like material and methods of making such devices is provided. At least one of the donor-like material and the acceptor-like material includes a subphthalocyanine, a subporphyrin, and/or a subporphyrazine compound; and/or the device optionally has at least one of a blocking layer or a charge transport layer, where the blocking layer and/or the charge transport layer includes a subphthalocyanine, a subporphyrin, and/or a subporphyrazine compound.

Rand, Barry (Princeton, NJ); Forrest, Stephen R. (Ann Arbor, MI); Mutolo, Kristin L. (Hollywood, CA); Mayo, Elizabeth (Alhambra, CA); Thompson, Mark E. (Anaheim Hills, CA)

2011-07-05

81

Toxic organic compounds from energy production  

SciTech Connect

The US Department of Energy's Office of Health and Environmental Research (OHER) has supported work in our laboratory since 1977. The general theme of this program has been the identification of potentially toxic organic compounds associated with various combustion effluents, following the fates of these compounds in the environment, and improving the analytical methodology for making these measurements. The projects currently investigation include: an improved sampler for semi-volatile compounds in the atmosphere; the wet and dry deposition of dioxins and furans from the atmosphere; the photodegradation and mobile sources of dioxins and furans; and the bioaccumulation of PAH by tree bark. These projects are all responsive to OHER's interest in the pathways and mechanisms by which energy-related agents move through and are modified by the atmosphere''. The projects on gas chromatographic and liquid chromatographic tandem mass spectrometry are both responsive to OHER's interest in new and more sensitive technologies for chemical measurements''. 35 refs., 9 figs.

Hites, R.A.

1991-09-20

82

A model-based assessment of the potential use of compound-specific stable isotope analysis in river monitoring of diffuse pesticide pollution  

NASA Astrophysics Data System (ADS)

Compound-specific stable isotope analysis (CSIA) has, in combination with model-assisted interpretation, proven to be a valuable approach to quantify the extent of organic contaminant degradation in groundwater systems. CSIA data may also provide insights into the origin and transformation of diffuse pollutants, such as pesticides and nitrate, at the catchment scale. While CSIA methods for pesticides have increasingly become available, they have not yet been deployed to interpret isotope data of pesticides in surface water. We applied a coupled subsurface-surface reactive transport model (HydroGeoSphere) at the hillslope scale to investigate the usefulness of CSIA in the assessment of pesticide degradation. We simulated the transport and transformation of a pesticide in a hypothetical but realistic two-dimensional hillslope transect. The steady-state model results illustrate a strong increase of isotope ratios at the hillslope outlet, which resulted from degradation and long travel times through the hillslope during average hydrological conditions. In contrast, following an extreme rainfall event that induced overland flow, the simulated isotope ratios dropped to the values of soil water in the pesticide application area. These results suggest that CSIA can help to identify rainfall-runoff events that entail significant pesticide transport to the stream via surface runoff. Simulations with daily rainfall and evapotranspiration data and one pesticide application per year resulted in small seasonal variations of concentrations and isotope ratios at the hillslope outlet, which fell within the uncertainty range of current CSIA methods. This implies a good reliability of in-stream isotope data in the absence of transport via surface runoff or other fast transport routes, since the time of measurement appears to be of minor importance for the assessment of pesticide degradation. The analysis of simulated isotope ratios also allowed quantification of the contribution of two different reaction pathways (aerobic and anaerobic) to overall degradation, which gave further insight into the transport routes in the modelled system. The simulations supported the use of the commonly applied Rayleigh equation for the interpretation of CSIA data, since this led to an underestimation of the real extent of degradation of less than 12% at the hillslope outlet. Overall, this study emphasizes the applicability and usefulness of CSIA in the assessment of diffuse river pollution, and represents a first step towards a theoretical framework for the interpretation of CSIA data in agricultural catchments.

Lutz, S. R.; van Meerveld, H. J.; Waterloo, M. J.; Broers, H. P.; van Breukelen, B. M.

2013-11-01

83

Organic compounds and trace elements in the Pocomoke River and its tributaries  

USGS Publications Warehouse

In response to concern about recent blooms of the dinoflagellate, Pfiesteria piscicida, samples of sediment and water were collected from the lower Pocomoke River Basin and were screened for trace elements, pesticides, and other organic compounds. A large group of steroid and fatty acid methyl-ester compounds was detected in streamwater using gas chromatography/mass spectroscopy in scan mode. Some of these steroid compounds have been identified and further quantified in bed-sediment extracts. Spatial patterns of the concentrations of cholesterol suggest that these compounds are linked to the runoff of animal wastes into the river. Many of the organic compounds found in the Pocomoke River sediments have not yet been identified, but at least several are in the class of hormone compounds related to estradiols and have the potential to promote endocrine-disrupting effects in aquatic life. Particulate forms of arsenic and zinc are slightly elevated above normal levels for streams, but the sources for these elements are still undetermined. Several pesticides were found in low, parts-per-trillion concentrations, but were within the ranges commonly found in streams of this region.

Miller, Cherie V.; Foster, Gregory D.; Huff, Thomas B.; Garbarino, John R.

1999-01-01

84

Organic compounds in star forming regions.  

PubMed

The influence of complex dust composition on the general chemical evolution of a prestellar core and the content of complex organic compounds is studied. It is shown that various component groups respond differently to the presence of a small dust population. At early stages the difference is determined primarily by changes in the balance of photo processes due to effective absorption of ultraviolet photons by small dust grains of the second population and collisional reactions with dust particles. At later stages differences are also caused by the growing dominance of additional reaction channels related to surface organic synthesis. PMID:25515345

Kochina, O; Wiebe, D

2014-09-01

85

Metabolic Reactions among Organic Sulfur Compounds  

NASA Technical Reports Server (NTRS)

Sulfur is central to the metabolisms of many organisms that inhabit extreme environments. Numerous authors have addressed the energy available from a variety of inorganic sulfur redox pairs. Less attention has been paid, however, to the energy required or gained from metabolic reactions among organic sulfur compounds. Work in this area has focused on the oxidation of alkyl sulfide or disulfide to thiol and formaldehyde, e.g. (CH3)2S + H2O yields CH3SH + HCHO + H2, eventually resulting in the formation of CO2 and SO4(-2). It is also found that reactions among thiols and disulfides may help control redox disequilibria between the cytoplasm and the periplasm. Building on our earlier efforts for thiols, we have compiled and estimated thermodynamic properties for alkyl sulfides. We are investigating metabolic reactions among various sulfur compounds in a variety of extreme environments, ranging from sea floor hydrothermal systems to organic-rich sludge. Using thermodynamic data and the revised HKF equation of state, along with constraints imposed by the geochemical environments sulfur-metabolizing organisms inhabit, we are able to calculate the amount of energy available to these organisms.

Schulte, M.; Rogers, K.

2005-01-01

86

If your budget balks at organic food prices, here is a guide to the best choices based on pesticide residue levels typically  

E-print Network

) The following foods consistently have HIGH levels of pesticide residues -- choose organic or other low-pesticide options when possible. The following foods consistently have LOW levels of pesticide residues. BioIf your budget balks at organic food prices, here is a guide to the best choices based on pesticide

87

Self assembly properties of primitive organic compounds  

NASA Technical Reports Server (NTRS)

A central event in the origin of life was the self-assembly of amphiphilic, lipid-like compounds into closed microenvironments. If a primitive macromolecular replicating system could be encapsulated within a vesicular membrane, the components of the system would share the same microenvironment, and the result would be a step toward true cellular function. The goal of our research has been to determine what amphiphilic molecules might plausibly have been available on the early Earth to participate in the formation of such boundary structures. To this end, we have investigated primitive organic mixtures present in carbonaceous meteorites such as the Murchison meteorite, which contains 1-2 percent of its mass in the form of organic carbon compounds. It is likely that such compounds contributed to the inventory of organic carbon on the prebiotic earth, and were available to participate in chemical evolution leading to the emergence of the first cellular life forms. We found that Murchison components extracted into non-polar solvent systems are surface active, a clear indication of amphiphilic character. One acidic fraction self-assembles into vesicular membranes that provide permeability barriers to polar solutes. Other evidence indicates that the membranes are bimolecular layers similar to those formed by contemporary membrane lipids. We conclude that bilayer membrane formation by primitive amphiphiles on the early Earth is feasible. However, only a minor fraction of acidic amphiphiles assembles into bilayers, and the resulting membranes require narrowly defined conditions of pH and ionic composition to be stable. It seems unlikely, therefore, that meteoritic infall was a direct source of membrane amphiphiles. Instead, the hydrocarbon components and their derivatives more probably would provide an organic stock available for chemical evolution. Our current research is directed at possible reactions which would generate substantial quantities of membranogenic amphiphiles. One possibility is photochemical oxidation of hydrocarbons.

Deamer, D. W.

1991-01-01

88

Effects of an Organochlorine Pesticide on Different Levels of Biological Organization in Daphnia  

Microsoft Academic Search

The toxicity of the organochlorine pesticide, endosulfan, toDaphnia carinatawas measured at three levels of biological organization: allocation of resources to reproduction, growth and reproductive rates, and population dynamics. The mechanisms by which responses at one level of organization manifest at higher levels are discussed. Two experiments were performed: in the first experiment, groups ofDaphniawere exposed to endosulfan at one of

Michael J. Barry

1996-01-01

89

Production of volatile organic compounds by mycobacteria.  

PubMed

The need for improved rapid diagnostic tests for tuberculosis disease has prompted interest in the volatile organic compounds (VOCs) emitted by Mycobacterium tuberculosis complex bacteria. We have investigated VOCs emitted by Mycobacterium bovis BCG grown on Lowenstein-Jensen media using selected ion flow tube mass spectrometry and thermal desorption-gas chromatography-mass spectrometry. Compounds observed included dimethyl sulphide, 3-methyl-1-butanol, 2-methyl-1-propanol, butanone, 2-methyl-1-butanol, methyl 2-methylbutanoate, 2-phenylethanol and hydrogen sulphide. Changes in levels of acetaldehyde, methanol and ammonia were also observed. The compounds identified are not unique to M. bovis BCG, and further studies are needed to validate their diagnostic value. Investigations using an ultra-rapid gas chromatograph with a surface acoustic wave sensor (zNose) demonstrated the presence of 2-phenylethanol (PEA) in the headspace of cultures of M. bovis BCG and Mycobacterium smegmatis, when grown on Lowenstein-Jensen supplemented with glycerol. PEA is a reversible inhibitor of DNA synthesis. It is used during selective isolation of gram-positive bacteria and may also be used to inhibit mycobacterial growth. PEA production was observed to be dependent on growth of mycobacteria. Further study is required to elucidate the metabolic pathways involved and assess whether this compound is produced during in vivo growth of mycobacteria. PMID:22224870

McNerney, Ruth; Mallard, Kim; Okolo, Phyllis Ifeoma; Turner, Claire

2012-03-01

90

Environmental exposure to pesticides and cancer risk in multiple human organ systems.  

PubMed

There is growing evidence on the association between long-term exposure to pesticides in occupational settings and an elevated rate of chronic diseases, including different types of cancer. However, data on non-occupational exposures are scarce to draw any conclusion. The objective of this study was to investigate the putative associations of environmental pesticide exposures in the general population with several cancer sites and to discuss potential carcinogenic mechanisms by which pesticides develop cancer. A population-based case-control study was conducted among people residing in 10 Health districts from Andalusia (South Spain) to estimate the risk of cancer at different sites. Health districts were categorized into areas of high and low environmental pesticide exposure based on two quantitative criteria: number of hectares devoted to intensive agriculture and pesticide sales per capita. The study population consisted of 34,205 cancer cases and 1,832,969 age and health district matched controls. Data were collected by computerized hospital records (minimum dataset) between 1998 and 2005. Prevalence rates and the risk of cancer at most organ sites were significantly higher in districts with greater pesticide use related to those with lower pesticide use. Conditional logistic regression analyses showed that the population living in areas with high pesticide use had an increased risk of cancer at all sites studied (odds ratios between 1.15 and 3.45) with the exception of Hodgkin's disease and non-Hodgkin lymphoma. The results of this study support and extend previous evidence from occupational studies indicating that environmental exposure to pesticides may be a risk factor for different types of cancer at the level of the general population. PMID:24269242

Parrón, Tesifón; Requena, Mar; Hernández, Antonio F; Alarcón, Raquel

2014-10-15

91

Organic compounds in White River water used for public supply near Indianapolis, Indiana, 2002-05  

USGS Publications Warehouse

The National Water-Quality Assessment (NAWQA) Program of the U.S. Geological Survey (USGS) characterized the occurrence of 277 organic compounds in source water (stream water collected before treatment) and finished water (treated water before distribution) from the White River North treatment plant, one of several community water systems that use the White River as its primary water supply (fig. 1). Samples were collected at least monthly during 2002-05 and included 30 source- and 13 finished-water samples. The samples were analyzed for pesticides and selected pesticide degradates (or 'breakdown products'), solvents, gasoline hydrocarbons, disinfection by-products, personal-care and domestic-use products, and other organic compounds. Community water systems are required to monitor for compounds regulated under the Safe Drinking Water Act. Most of the compounds tested in this study are not regulated under U.S. Environmental Protection Agency (USEPA) federal drinking-water standards (U.S. Environmental Protection Agency, 2007a). The White River study is part of the ongoing Source Water-Quality Assessment (SWQA) investigation of community water systems that withdraw from rivers across the United States. More detailed information and references on the sampling-design methodology, specific compounds monitored, and the national study are described by Carter and others (2007).

Lathrop, Tim; Moran, Dan

2011-01-01

92

Selected phenolic compounds in cultivated plants: ecologic functions, health implications, and modulation by pesticides.  

PubMed Central

Phenolic compounds are widely distributed in the plant kingdom. Plant tissues may contain up to several grams per kilogram. External stimuli such as microbial infections, ultraviolet radiation, and chemical stressors induce their synthesis. The phenolic compounds resveratrol, flavonoids, and furanocoumarins have many ecologic functions and affect human health. Ecologic functions include defense against microbial pathogens and herbivorous animals. Phenolic compounds may have both beneficial and toxic effects on human health. Effects on low-density lipoproteins and aggregation of platelets are beneficial because they reduce the risk of coronary heart disease. Mutagenic, cancerogenic, and phototoxic effects are risk factors of human health. The synthesis of phenolic compounds in plants can be modulated by the application of herbicides and, to a lesser extent, insecticides and fungicides. The effects on ecosystem functioning and human health are complex and cannot be predicted with great certainty. The consequences of the combined natural and pesticide-induced modulating effects for ecologic functions and human health should be further evaluated. PMID:10229712

Daniel, O; Meier, M S; Schlatter, J; Frischknecht, P

1999-01-01

93

Palladium catalyzed hydrogenation of bio-oils and organic compounds  

DOEpatents

The invention provides palladium-catalyzed hydrogenations of bio-oils and certain organic compounds. Experimental results have shown unexpected and superior results for palladium-catalyzed hydrogenations of organic compounds typically found in bio-oils.

Elliott, Douglas C. (Richland, WA); Hu, Jianli (Kennewick, WA); Hart, Todd R. (Kennewick, WA); Neuenschwander, Gary G. (Burbank, WA)

2008-09-16

94

40 CFR 60.742 - Standards for volatile organic compounds.  

Code of Federal Regulations, 2011 CFR

... 2011-07-01 false Standards for volatile organic compounds. 60.742 Section 60.742 Protection of Environment...Substrates Facilities § 60.742 Standards for volatile organic compounds. (a) Each owner or operator of an affected...

2011-07-01

95

40 CFR 60.392 - Standards for volatile organic compounds  

Code of Federal Regulations, 2011 CFR

... 2011-07-01 false Standards for volatile organic compounds 60.392 Section 60.392 Protection of Environment...Coating Operations § 60.392 Standards for volatile organic compounds On and after the date on which the initial...

2011-07-01

96

40 CFR 60.492 - Standards for volatile organic compounds.  

Code of Federal Regulations, 2010 CFR

... 2010-07-01 false Standards for volatile organic compounds. 60.492 Section 60.492 Protection of Environment...Coating Industry § 60.492 Standards for volatile organic compounds. On or after the date on which the initial...

2010-07-01

97

40 CFR 60.392 - Standards for volatile organic compounds  

Code of Federal Regulations, 2010 CFR

... 2010-07-01 false Standards for volatile organic compounds 60.392 Section 60.392 Protection of Environment...Coating Operations § 60.392 Standards for volatile organic compounds On and after the date on which the initial...

2010-07-01

98

40 CFR 60.492 - Standards for volatile organic compounds.  

Code of Federal Regulations, 2011 CFR

... 2011-07-01 false Standards for volatile organic compounds. 60.492 Section 60.492 Protection of Environment...Coating Industry § 60.492 Standards for volatile organic compounds. On or after the date on which the initial...

2011-07-01

99

Anthropogenic Organic Compounds in Ground Water and Finished Water of Community Water Systems near Dayton, Ohio, 2002-04  

USGS Publications Warehouse

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.

Thomas, Mary Ann

2007-01-01

100

Synthetic organic compounds and their transformation products in groundwater: occurrence, fate and mitigation.  

PubMed

Groundwater constitutes the main source of public drinking water supply in many regions. Thus, the contamination of groundwater resources by organic chemicals is a matter of growing concern because of its potential effects on public health. The present manuscript compiles the most recent works related to the study of synthetic organic compounds (SOCs) in groundwater, with special focus on the occurrence of contaminants not or barely covered by previously published reviews, e.g., pesticide and pharmaceutical transformation products, lifestyle products, and industrial chemicals such as corrosion inhibitors, brominated and organophosphate flame retardants, plasticizers, volatile organic compounds (VOCs), and polycyclic aromatic hydrocarbons (PAHs). Moreover, the main challenges in managed aquifer recharge, i.e., reclaimed water injection and infiltration, and riverbank filtration, regarding natural attenuation of organic micropollutants are discussed, and insights into the future chemical quality of groundwater are provided. PMID:24974362

Postigo, Cristina; Barceló, Damià

2015-01-15

101

Rate coefficients of hydroxyl radical reactions with pesticide molecules and related compounds: A review  

NASA Astrophysics Data System (ADS)

Rate coefficients published in the literature on hydroxyl radical reactions with pesticides and related compounds are discussed together with the experimental methods and the basic reaction mechanisms. Recommendations are made for the most probable values. Most of the molecules whose rate coefficients are discussed have aromatic ring: their rate coefficients are in the range of 2×109-1×1010 mol-1 dm3 s-1. The rate coefficients show some variation with the electron withdrawing-donating nature of the substituent on the ring. The rate coefficients for triazine pesticides (simazine, atrazine, prometon) are all around 2.5×109 mol-1 dm3 s-1. The values do not show variation with the substituent on the s-triazine ring. The rate coefficients for the non-aromatic molecules which have C=C double bonds or several C-H bonds may also be above 1×109 mol-1 dm3 s-1. However, the values for molecules without C=C double bonds or several C-H bonds are in the 1×107-1×109 mol-1 dm3 s-1 range.

Wojnárovits, László; Takács, Erzsébet

2014-03-01

102

Biogenic volatile organic compounds - small is beautiful  

NASA Astrophysics Data System (ADS)

While canopy and regional scale flux measurements of biogenic volatile organic compounds (bVOCs) are essential to obtain an integrated picture of total compound reaching the atmosphere, many fascinating and important emission details are waiting to be discovered at smaller scales, in different ecological and functional compartments. We concentrate on bVOCs below ground to <2m above ground level. Emissions at leaf scale are well documented and widely presented, and are not discussed here. Instead we describe some details of recent research on rhizosphere bVOCs, and bVOCs associated with pollination of flowers. Although bVOC emissions from soil surfaces are small, bVOCs are exuded by roots of some plant species, and can be extracted from decaying litter. Naturally occurring monoterpenes in the rhizosphere provide a specialised carbon source for micro-organisms, helping to define the micro-organism community structure, and impacting on nutrient cycles which are partly controlled by microorganisms. Naturally occurring monoterpenes in the soil system could also affect the aboveground structure of ecosystems because of their role in plant defence strategies and as mediating chemicals in allelopathy. A gradient of monoterpene concentration was found in soil around Pinus sylvestris and Pinus halepensis, decreasing with distance from the tree. Some compounds (?-pinene, sabinene, humulene and caryophyllene) in mineral soil were linearly correlated with the total amount of each compound in the overlying litter, indicating that litter might be the dominant source of these compounds. However, ?-pinene did not fall within the correlation, indicating a source other than litter, probably root exudates. We also show that rhizosphere bVOCs can be a carbon source for soil microbes. In a horizontal gradient from Populus tremula trees, microbes closest to the tree trunk were better enzymatically equipped to metabolise labeled monoterpene substrate. Monoterpenes can also increase the degradation rate in soil of the persistant organic pollutants, likely acting as analogues for the cometabo-lism of polychlorinated biphenyls (PCBs) Flowers of a ginger species (Alpinia kwangsiensis) and a fig species (Ficus hispida) showed different bVOC signals pre- and post pollination. For Ficus hispida, there are three floral stages of a fig-wasp dependency mechanism: receptive, post pollinator and interfloral. Of 28 compounds detected, transcaryophyllene with trans-?-farnesene were the most important at the receptor stage, trans-caryophyllene was the most abundant at the post-pollinator stage, and isoprene was the most abundant in the interfloral stage. Alpinia kwangsiensis presents two morphologies for the reproductive parts of the flower. The "anaflexistyle" morphology has the flower style lowered in the morning and raised in the afternoon. This is reversed for the "cataflexistyle" morphology. The bVOC mixture emitted by each morphology in morning and afternoon was complex. However for compounds showing a difference (cis-ocimene and Z + E epoxy -ocimene), the emissions from the anaflexistyle were greater than from the cataflexistyle, and were greater in the afternoon compared with the morning emissions. Where large flowering plant species are abundant, big changes in monoterpene emissions at < 2m above ground level over relatively small periods of time during pollination are likely to be missed in larger scale integrated flux measurements.

Owen, S. M.; Asensio, D.; Li, Q.; Penuelas, J.

2012-12-01

103

Actellic 2% Dust as Pesticide in Feed Ingredients: Post-Weaning Tolerance, Growth Performance and Organ Weights of Growing Rabbits  

Microsoft Academic Search

The study was designed to evaluate the tolerance, survivability and performance of weaner rabbits fed varying levels of actellic dust. The pathological effects of the pesticide on the animals were also appraised. A uniform diet was compounded from ingredients certified to be apparently pesticide residue-free. This diet was partitioned into 5 sub-diets. The first partition A had no residue, serving

J. M. Omoyakhi; A. M. Orheruata

2009-01-01

104

THE DETERMINATION OF NON-PESTICIDAL AND PESTICIDAL ORGANOTIN COMPOUNDS IN WATER BY GAS CHROMATOGRAPHY WITH [PULSED] FLAME PHOTOMETRIC DETECTION (GS/PFPD): THE EFFECTS OF "MASS" DISCRIMINATION  

EPA Science Inventory

Capillary gas chromatography with GC/PFPD was used in the development of analytical methodology for determining both non-pesticidal and pesticidal organotin compounds in drinking water and other aqueous matrices. The method involves aqueous ethylation of organotin analytes with ...

105

Volatile Organic Compound Analysis in Istanbul  

NASA Astrophysics Data System (ADS)

Volatile Organic Compound Analysis in Istanbul Ö. Çapraz1, A. Deniz1,3, A. Ozturk2, S. Incecik1, H. Toros1 and, M. Coskun1 (1) Istanbul Technical University, Faculty of Aeronautics and Astronautics, Department of Meteorology, 34469, Maslak, Istanbul, Turkey. (2) Istanbul Technical University, Faculty of Chemical and Metallurgical, Chemical Engineering, 34469, Maslak, Istanbul, Turkey. (3) Marmara Clean Air Center, Ministry of Environment and Urbanization, Ni?anta??, 34365, ?stanbul, Turkey. One of the major problems of megacities is air pollution. Therefore, investigations of air quality are increasing and supported by many institutions in recent years. Air pollution in Istanbul contains many components that originate from a wide range of industrial, heating, motor vehicle, and natural emissions sources. VOC, originating mainly from automobile exhaust, secondhand smoke and building materials, are one of these compounds containing some thousands of chemicals. In spite of the risks to human health, relatively little is known about the levels of VOC in Istanbul. In this study, ambient air quality measurements of 32 VOCs including hydrocarbons, halogenated hydrocarbons and carbonyls were conducted in Ka??thane (Golden Horn) region in Istanbul during the winter season of 2011 in order to develop the necessary scientific framework for the subsequent developments. Ka??thane creek valley is the source part of the Golden Horn and one of the most polluted locations in Istanbul due to its topographical form and pollutant sources in the region. In this valley, horizontal and vertical atmospheric motions are very weak. The target compounds most commonly found were benzene, toluene, xylene and ethyl benzene. Concentrations of total hydrocarbons ranged between 1.0 and 10.0 parts per billion, by volume (ppbv). Ambient air levels of halogenated hydrocarbons appeared to exhibit unique spatial variations and no single factor seemed to explain trends for this group of compounds. N-octane, 3-methylheptane, n-nonane, 2,3,4-trimethylpentane and n-hexane parameters ranged between 3 ppbv and maximum value of 10 ppbv. The other VOC parameters are measured below 3 ppbv value. At participating urban locations for the year of data considered, levels of carbonyls were higher than the level of the other organic compound groups, suggesting that emissions from motor vehicles and photochemical reactions strongly in?uence ambient air concentrations of carbonyls. Of the most prevalent carbonyls, formaldehyde and acetaldehyde were the dominant compounds, ranging from 1.5-7.4 ppbv for formaldehyde, to 0.8-2.7 ppbv for acetaldehyde. Keywords: Air quality, Volatile Organic Compounds (VOC), industry, meteorology, urban, Ka??thane, ?stanbul. Acknowledgment: This work was part of the TUJJB-TUMEHAP-01-10 and Turkish Scientific and Technical Research Council Project No: 109Y132.

?apraz, Ö.; Deniz, A.; Öztürk, A.; Incecik, S.; Toros, H.; Co?kun, M.

2012-04-01

106

Study on the distribution of organic carbon in soil fractions and its reaction potential of binding the pesticides  

NASA Astrophysics Data System (ADS)

STUDY ON THE DISTRIBUTION OF ORGANIC CARBON IN SOIL FRACTIONS AND ITS REACTION POTENTIAL OF BINDING THE PESTICIDES **SUMITRA ROY1, SANKHAJIT ROY1, *ASHIM CHOWDHURY2, SASWATI PRADHAN2 and PETER BURAUEL3 1Department of Agricultural Chemicals, Bidhan Chandra Krishi Viswavidyalay, Mohanpur, West Bengal, India. 2Department of Agricultural Chemistry and Soil Science, University of Calcutta, West Bengal, India. 3Institute of Chemical Dynamics & Geosphere, FZ-Juelich, Germany. *Correspondence: ashimkly@hotmail.com **Research work carried out as DAAD Sandwich research fellow at FZ- Juelich, Germany Soil is the ultimate sink of all selectively applied pesticides. In addition to the basic physicochemical data of an active ingredient, the fate of the various compounds is largely determined by the type of application. Finally, pesticide and their metabolites, as well as structural elements, remain in the native carbon reserves of the soil or are sorbed & fixed to clay minerals and clay- humus complexes. Soil organic matter (SOM) and the soil microbial community are the crucial components which regulate soil processes and contribute towards the stability of the soil ecosystem. It is an energy source for biological mineralization processes, functions as a buffer and participates in chemical reaction. Knowledge is essential to understand the extent to which the SOM influences the mobilization and immobilization processes of foreign substance in soil and the substance transport and pollutant decomposition in soil. The freshly incorporated organic matter undergoes mineralization and the non mineralized carbon fraction is of special relevance with respect to soil stability in general and decisive for the fate and particular the persistence of xenobiotics in soil. The biological and physicochemical interactions establishing equilibrium between the organic matter bound, fixed or complexed to the soil matrix and that dissolve in the soil solution must be understood in detail to realize soil and groundwater conservation. The radio-tracer technology emerged as the latest technology in agriculture, which helps in studying the translocation of pesticide along with the organic matter and furthermore, the distribution of the pesticide in the soil phases. For the elucidation of these relationships and distribution of organic carbon in soil fractions and its reaction potential of binding the pesticides, the present laboratory study was undertaken using 14C-enriched and non labeled maize straw as a source of fresh SOM in different soil fractions vis-à-vis its effect on distribution of 14C-labeled benazolin and non labeled benazolin (a selective, post emergence herbicide) as a xenobiotics throughout the soil system. To determine the turnover of SOM fractionation of top layer of the both the benazolin treated soil column was done followed by determination of 14C content in four different soil phases obtained from fraction, characterization of different phase and identification of the metabolites with TLC, HPLC and GC-MS. The result clearly indicated that where soil columns received non- labeled maize straw and 14C-benazolin as well as 14C-labeled maize straw and nonlabeled benazolin; the unit weight distribution study of radioactivity in benazolin followed the decreasing trend in different phases in following order of electrolyte>colloidal> micro aggregate > sediment phases respectively. The percentage distribution of maize straw (fresh organic matter) was also found highest in electrolyte phase followed the same order as in the case of benazolin. It was observed in phase-wise distribution study that radioactivity either of 14C-maize straw or 14C-benazolin was mostly concentrated in the sediment phase followed by micro aggregate, colloidal and electrolyte phase. From this it was clear that the soil columns, which received maize straw, have bound the pesticide benazolin and hindered the translocation to the lower layers leading to higher percentage of recovered radioactivity at top layer. Thus, these two results can be correlated in

Chowdhury, Ashim

2010-05-01

107

Water solubility enhancement of some organic pollutants and pesticides by dissolved humic and fulvic acids  

Microsoft Academic Search

Water solubility enhancements by dissolved humic and fulvic acids from soil and aquatic origins and by synthetic organic polymers have been determined for selected organic pollutants and pesticides (p,p'-DDT,2,4,5,2',5'-PCB, 2,4,4'-PCB, 1,2,3,-trichlorobenzene, and lindane). Significant solubility enhancements of relatively water-insoluble solutes by dissolved organic matter (DOM) of soil and aquatic origins may be described in terms of a partition-like interaction of

Cary T. Chiou; Ronald L. Malcolm; Terry I. Brinton; Daniel E. Kile

1986-01-01

108

Pesticide Use and Toxicology in Relation to Wildlife: Organophosphorus and Carbamate , Compounds  

Microsoft Academic Search

The use of organophosphorus and carbamate pesticides has increased markedly during the past two decades. Currently, more than 100 different organophosphorus and carbamate chemicals are registered as the active ingredients in thousands of different pesticide products in the United States. More than 160 million acre-treatments of these pesticides are estimated to be applied to agricultural crops and forests each year.

Gregory J. Smith

1987-01-01

109

Distribution of organic and organometallic compounds in sediments from the Louisianian Province  

SciTech Connect

In 1994, over 200 sediment samples were collected in accordance with EPA`s EMAP probabilistic sampling protocol from coastal and estuarine areas in the Louisianian Province (Gulf of Mexico). These samples represent a homogenate of 3 to 5 grabs from which the top 2 cm of surficial sediments were extracted. These samples were frozen and shipped to the Skidaway Institute of Oceanography for analysis of metal and organic constituents. Frozen sediments were freeze dried and up to 40 g were soxhlet extracted with CH{sub 2}Cl{sub 2}. This extract was then divided into several sub-aliquots for analysis of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides, organophosphate pesticides and organotin (butyl- and phenyltins) compounds. Interferences were removed using packed column chromatography and split extracts were analyzed by GC with the appropriate detection technique.

Maruya, K.; Ertel, J.; Loganathan, B. [Skidaway Inst. of Oceanography, Savannah, GA (United States)] [and others

1996-12-31

110

Pesticides and other micro-organic contaminants in freshwater sedimentary environments—a review  

Microsoft Academic Search

A wide range of issues relating to the presence and fate of pesticides and other micro-organic contaminants (MOCs) in surface freshwater sedimentary environments is reviewed. These issues include the sources, transport and occurrence of MOCs in freshwater environments; their ecological effects; their interaction with sedimentary material; and a range of processes related to their fate, including degradation, diffusion in bed

N. Warren; I. J. Allan; J. E. Carter; W. A. House; A. Parker

2003-01-01

111

Antioxidant substances and pesticide in parts of beet organic and conventional manure  

Microsoft Academic Search

Organic agriculture together with sustainable management systems are growing in the world due to concerns about the environment and the health of the populace: being real and exhaustively documented the damages caused by pesticides. The aim of this work was to observe the possible differences in the concentrations of free radical scavengers and substances recently classified as functional, in different

Maria Rosecler Miranda Rossetto; Fabio Vianello; Suraya Abdallah da Rocha; Giuseppina Pace; Pereira Lima

112

Charge Ordering in Organic ET Compounds  

NASA Astrophysics Data System (ADS)

The charge ordering phenomena in quasi two-dimensional 1/4-filled organic compounds (ET)2X (ET=BEDT-TTF) are investigated theoreticallyfor the ? and ?-type structures, based on the Hartree approximation for the extended Hubbard models with both on-site and intersite Coulomb interactions.It is found that charge ordered states of stripe-type are stabilized for the relevant values of Coulomb energies, while the spatial pattern of the stripes sensitively depends on the anisotropy of the models. By comparing the results of calculations with the experimental facts, where the effects of quantum fluctuation is incorporated by mapping the stripe-type charge ordered states to the S=1/2 Heisenberg Hamiltonians, the actual charge patterns in the insulating phases of ?-(ET)2MM'(SCN)4 and ?-(ET)2I3 are deduced. Furthermore, to obtain a unified view among the ?, ? and ?-(ET)2X families, the stability of the charge ordered state in competition with the dimeric antiferromagnetic state viewed as the Mott insulating state, which is typically realized in ?-type compounds, and with the paramagnetic metallic state, is also pursued by extracting essential parameters.

Seo, Hitoshi

2000-03-01

113

Efficiency of conventional drinking-water-treatment processes in removal of pharmaceuticals and other organic compounds  

USGS Publications Warehouse

Samples of water and sediment from a conventional drinking-water-treatment (DWT) plant were analyzed for 113 organic compounds (OCs) that included pharmaceuticals, detergent degradates, flame retardants and plasticizers, polycyclic aromatic hydrocarbons (PAHs), fragrances and flavorants, pesticides and an insect repellent, and plant and animal steroids. 45 of these compounds were detected in samples of source water and 34 were detected in samples of settled sludge and (or) filter-backwash sediments. The average percent removal of these compounds was calculated from their average concentration in time-composited water samples collected after clarification, disinfection (chlorination), and granular-activated-carbon (GAC) filtration. In general, GAC filtration accounted for 53% of the removal of these compounds from the aqueous phase; disinfection accounted for 32%, and clarification accounted for 15%. The effectiveness of these treatments varied widely within and among classes of compounds; some hydrophobic compounds were strongly oxidized by free chlorine, and some hydrophilic compounds were partly removed through adsorption processes. The detection of 21 of the compounds in 1 or more samples of finished water, and of 3 to 13 compounds in every finished-water sample, indicates substantial but incomplete degradation or removal of OCs through the conventional DWT process used at this plant. ?? 2007 Elsevier B.V. All rights reserved.

Stackelberg, P.E.; Gibs, J.; Furlong, E.T.; Meyer, M.T.; Zaugg, S.D.; Lippincott, R.L.

2007-01-01

114

Human Semen Quality in Relation to Dietary Pesticide Exposure and Organic Diet  

Microsoft Academic Search

.   The objective of the study was to corroborate or refute the hypothesis that farmers having a high intake of organic grown\\u000a commodities have a high semen quality due to their expected lower level of dietary pesticides intake. Food frequency data\\u000a and semen were collected from 256 farmers (171 traditional farmers and 85 organic farmers, overall participation rate: 32%)\\u000a who

R. K. Juhler; S. B. Larsen; O. Meyer; N. D. Jensen; M. Spanò; A. Giwercman; J. P. Bonde

1999-01-01

115

ACUTE TOXICITY OF SELECTED ORGANIC COMPOUNDS TO FATHEAD MINNOWS  

EPA Science Inventory

Static nonrenewal laboratory bioassays were conducted with 26 organic compounds commonly used by industry. The selected compounds represented the five following chemical classes: acids, alcohols, hydrocarbons, ketones and aldehydes, and phenols. Juvenile fathead minnows (Pimephal...

116

Use of Polar Organic Chemical Integrative Samplers to assess the effects of chronic pesticide exposure on biofilms  

E-print Network

conditions (reference site) and in sites exposed to pesticides (contaminated site). The exposure imposed 1 Use of Polar Organic Chemical Integrative Samplers to assess the effects of chronic pesticide exposure on biofilms Soizic Morin1, Stéphane Pesce2, Sandra KimTiam1, Xavier Libert1, Marina

Paris-Sud XI, Université de

117

ANALYTICAL METHODS DEVELOPED FOR THE CHILDREN'S TOTAL EXPOSURES TO PERSISTENT PESTICIDES AND OTHER PERSISTENT ORGANIC POLLUTANTS (CTEPP) STUDY  

EPA Science Inventory

The Children's Total Exposure to Persistent Pesticides and Other Persistent Organic Pollutants (CTEPP) study was designed by the U.S. EPA to collect data on young children's exposures to pesticides and other pollutants in their everyday environments in support of the Food Quality...

118

Soluble organic compounds in the Tagish Lake meteorite  

NASA Astrophysics Data System (ADS)

The C2 ungrouped Tagish Lake meteorite preserves a range of lithologies, reflecting variable degrees of parent-body aqueous alteration. Here, we report on soluble organic compounds, including aliphatic and aromatic hydrocarbons, monocarboxylic acids, and amino acids, found within specimens representative of the range of aqueous alteration. We find that differences in soluble organic compounds among the lithologies may be explained by oxidative, fluid-assisted alteration, primarily involving the derivation of soluble organic compounds from macromolecular material. In contrast, amino acids probably evolved from precursor molecules, albeit in parallel with other soluble organic compounds. Our results demonstrate the role of parent-body alteration in the modification of organic matter and generation of prebiotic compounds in the early solar system, and have implications for interpretation of the complement of soluble organic compounds in carbonaceous chondrites.

Hilts, Robert W.; Herd, Christopher D. K.; Simkus, Danielle N.; Slater, Greg F.

2014-04-01

119

Current challenges in compound-specific stable isotope analysis of environmental organic contaminants.  

PubMed

Compound-specific stable-isotope analysis (CSIA) has greatly facilitated assessment of sources and transformation processes of organic pollutants. Multielement isotope analysis is one of the most promising applications of CSIA because it even enables distinction of different transformation pathways. This review introduces the essential features of continuous-flow isotope-ratio mass spectrometry (IRMS) and highlights current challenges in environmental analysis as exemplified for the isotopes of nitrogen, hydrogen, chlorine, and oxygen. Strategies and recent advances to enable isotopic measurements of polar contaminants, for example pesticides or pharmaceuticals, are discussed with special emphasis on possible solutions for analysis of low concentrations of contaminants in environmental matrices. Finally, we discuss different levels of calibration and referencing and point out the urgent need for compound-specific isotope standards for gas chromatography-isotope-ratio mass spectrometry (GC-IRMS) of organic pollutants. PMID:22302163

Elsner, Martin; Jochmann, Maik A; Hofstetter, Thomas B; Hunkeler, Daniel; Bernstein, Anat; Schmidt, Torsten C; Schimmelmann, Arndt

2012-07-01

120

Pesticide residues in conventional, integrated pest management (IPM)-grown and organic foods: insights from three US data sets  

Microsoft Academic Search

An analysis of pesticide residue data was performed to describe and quantify differences between organically grown and non-organic fresh fruits and vegetables. Data on residues in foods from three different market categories (conventionally grown, integrated pest management (IPM)-grown\\/no detectable residues (NDR), and organically grown) were compared using data from three test programmes: The Pesticide Data Program of the US Department

B. P. Bakery; C. M. Benbrook; E. Groth III; K. Lutz Benbrook

2002-01-01

121

Method and reaction pathway for selectively oxidizing organic compounds  

DOEpatents

A method of selectively oxidizing an organic compound in a single vessel comprises: a) combining an organic compound, an acid solution in which the organic compound is soluble, a compound containing two oxygen atoms bonded to one another, and a metal ion reducing agent capable of reducing one of such oxygen atoms, and thereby forming a mixture; b) reducing the compound containing the two oxygen atoms by reducing one of such oxygen atoms with the metal ion reducing agent to, 1) oxidize the metal ion reducing agent to a higher valence state, and 2) produce an oxygen containing intermediate capable of oxidizing the organic compound; c) reacting the oxygen containing intermediate with the organic compound to oxidize the organic compound into an oxidized organic intermediate, the oxidized organic intermediate having an oxidized carbon atom; d) reacting the oxidized organic intermediate with the acid counter ion and higher valence state metal ion to bond the acid counter ion to the oxidized carbon atom and thereby produce a quantity of an ester incorporating the organic intermediate and acid counter ion; and e) reacting the oxidized organic intermediate with the higher valence state metal ion and water to produce a quantity of alcohol which is less than the quantity of ester, the acid counter ion incorporated in the ester rendering the carbon atom bonded to the counter ion less reactive with the oxygen containing intermediate in the mixture than is the alcohol with the oxygen containing intermediate.

Camaioni, Donald M. (Richland, WA); Lilga, Michael A. (Richland, WA)

1998-01-01

122

Molecular Models of Volatile Organic Compounds  

NSDL National Science Digital Library

This month's Featured Molecules come from the Report from Other Journals column, Nature: Our Atmosphere in the Year of Planet Earth, and the summary found there of the paper by Lelieveld et al. (1, 2) Added to the collection are several volatile organic compounds (VOCs) that are emitted by a variety of plants. The term VOCs is a common one in environmental chemistry, and is interpreted quite broadly, typically referring to any organic molecule with a vapor pressure sufficiently high to allow for part-per-billion levels in the atmosphere. Common VOCs include methane (the most prevalent VOC), benzene and benzene derivatives, chlorinated hydrocarbons, and many others. The source may be natural, as in the case of the plant emissions, or anthropogenic, as in the case of a molecule such as the gasoline additive methyl tert-butyl ether (MTBE).The oxidation of isoprene in the atmosphere has been a source of interest for many years. Several primary oxidation products are included in the molecule collection, although a number of isomeric forms are also possible (3).The area of VOCs provides innumerable topics for students research papers and projects at all levels of the curriculum from high-school chemistry through the undergraduate courses in chemistry and environmental science. Along the way students have the opportunity for exposure to fields such as epidemiology and toxicology, that may be new to them, but are of increasing importance in the environmental sciences. The MTBE story is an interesting one for students to discover, as it once again emphasizes the role that unintended consequences play in life. An exploration of the sources, structures, reactivity, health and environmental effects and ultimate fate of various VOCs reinforces in students minds just how interconnected the chemistry of the environment is, a lesson that bears repeating frequently.

123

Molecular classification of pesticides including persistent organic pollutants, phenylurea and sulphonylurea herbicides.  

PubMed

Pesticide residues in wine were analyzed by liquid chromatography-tandem mass spectrometry. Retentions are modelled by structure-property relationships. Bioplastic evolution is an evolutionary perspective conjugating effect of acquired characters and evolutionary indeterminacy-morphological determination-natural selection principles; its application to design co-ordination index barely improves correlations. Fractal dimensions and partition coefficient differentiate pesticides. Classification algorithms are based on information entropy and its production. Pesticides allow a structural classification by nonplanarity, and number of O, S, N and Cl atoms and cycles; different behaviours depend on number of cycles. The novelty of the approach is that the structural parameters are related to retentions. Classification algorithms are based on information entropy. When applying procedures to moderate-sized sets, excessive results appear compatible with data suffering a combinatorial explosion. However, equipartition conjecture selects criterion resulting from classification between hierarchical trees. Information entropy permits classifying compounds agreeing with principal component analyses. Periodic classification shows that pesticides in the same group present similar properties; those also in equal period, maximum resemblance. The advantage of the classification is to predict the retentions for molecules not included in the categorization. Classification extends to phenyl/sulphonylureas and the application will be to predict their retentions. PMID:24905607

Torrens, Francisco; Castellano, Gloria

2014-01-01

124

Volatile Organic Compound Emissions by Agricultural Crops  

NASA Astrophysics Data System (ADS)

Biogenic Volatile Organic Compounds (BVOCs) participate in ozone and aerosol formation, and comprise a substantial fraction of reactive VOC emission inventories. In the agriculturally intensive Central Valley of California, emissions from crops may substantially influence regional air quality, but emission potentials have not been extensively studied with advanced instrumentation for many important crops. Because crop emissions may vary according to the species, and California emission inventories are constructed via a bottom-up approach, a better knowledge of the emission rate at the species-specific level is critical for reducing uncertainties in emission inventories and evaluating emission model performance. In the present study we identified and quantified the BVOCs released by dominant agricultural crops in California. A screening study to investigate both volatile and semivolatile BVOC fractions (oxygenated VOCs, isoprene, monoterepenes, sesquiterpenes, etc.) was performed for 25 crop species (at least 3 replicates plants each), including branch enclosures of woody species (e.g. peach, mandarin, grape, pistachio) and whole plant enclosures for herbaceous species (e.g. onion, alfalfa, carrot), through a dynamic cuvette system with detection by PTRMS, in-situ GCMS/FID, and collection on carbon-based adsorbents followed by extraction and GCMS analysis. Emission data obtained in this study will allow inclusion of these crops in BVOC emission inventories and air quality simulations.

Ormeno, E.; Farres, S.; Gentner, D.; Park, J.; McKay, M.; Karlik, J.; Goldstein, A.

2008-12-01

125

FIELD SCREENING FOR HALOGENATED VOLATILE ORGANIC COMPOUNDS  

SciTech Connect

Western Research Institute (WRI) initiated exploratory work towards the development of new field screening methodology and a test kit to measure halogenated volatile organic compounds (VOCs) in the field. Heated diode and corona discharge sensors are commonly used to detect leaks of refrigerants from air conditioners, freezers, and refrigerators. They are both selective to the presence of carbon-halogen bonds. Commercially available heated diode and corona discharge leak detectors were procured and evaluated for halogenated VOC response. The units were modified to provide a digital readout of signal related to VOC concentration. Sensor response was evaluated with carbon tetrachloride and tetrachloroethylene (perchloroethylene, PCE), which represent halogenated VOCs with and without double bonds. The response characteristics were determined for the VOCs directly in headspace in Tedlar bag containers. Quantitation limits in air were estimated. Potential interferences from volatile hydrocarbons, such as toluene and heptane, were evaluated. The effect of humidity was studied also. The performance of the new devices was evaluated in the laboratory by spiking soil samples and monitoring headspace for halogenated VOCs. A draft concept of the steps for a new analytical method was outlined. The results of the first year effort show that both devices show potential utility for future analytical method development work towards the goal of developing a portable test kit for screening halogenated VOCs in the field.

John F. Schabron; Joseph F. Rovani Jr.; Theresa M. Bomstad

2002-06-01

126

Volatile organic compound remedial action project  

SciTech Connect

This Environmental Assessment (EA) reviews a proposed project that is planned to reduce the levels of volatile organic compound (VOC) contaminants present in the Mound domestic water supply. The potable and industrial process water supply for Mound is presently obtained from a shallow aquifer via on-site production wells. The present levels of VOCs in the water supply drawn from the on-site wells are below the maximum contaminant levels (MCLs) permissible for drinking water under Safe Drinking Water Act (SDWA; 40 CFR 141); however, Mound has determined that remedial measures should be taken to further reduce the VOC levels. The proposed project action is the reduction of the VOC levels in the water supply using packed tower aeration (PTA). This document is intended to satisfy the requirements of the National Environmental Policy Act (NEPA) of 1969 and associated Council on Environmental Quality regulations (40 CFR parts 1500 through 1508) as implemented through U.S. Department of Energy (DOE) Order 5440.1D and supporting DOE NEPA Guidelines (52 FR 47662), as amended (54 FR 12474; 55 FR 37174), and as modified by the Secretary of Energy Notice (SEN) 15-90 and associated guidance. As required, this EA provides sufficient information on the probable environmental impacts of the proposed action and alternatives to support a DOE decision either to prepare an Environmental Impact Statement (EIS) or issue a Finding of No Significant Impact (FONSI).

NONE

1991-12-01

127

Pesticide mobility and leachate toxicity in two abandoned mine soils. Effect of organic amendments.  

PubMed

Abandoned mine areas, used in the past for the extraction of minerals, constitute a degraded landscape which needs to be reintegrated to productive or leisure activities. However these soils, mainly composed by silt or sand and with low organic matter content, are vulnerable to organic and inorganic pollutants posing a risk to the surrounding ecosystems and groundwater. Soils from two mining areas from Andalusia were evaluated: one from Nerva (NCL) in the Iberian Pyrite Belt (SW Andalusia) and another one from the iron Alquife mine (ALQ) (SE Andalusia). To improve soil properties and fertility two amendments, stabilised sewage sludge (SSL) and composted sewage sludge (CSL), were selected. The effect of amendment addition on the mobility of two model pesticides, thiacloprid and fenarimol, was assessed using soil columns under non-equilibrium conditions. Fenarimol, more hydrophobic than thiacloprid, only leached from native ALQ, a soil with lower organic carbon (OC) content than NCL (0.21 and 1.4%, respectively). Addition of amendments affected differently pesticide mobility: thiacloprid in the leachates was reduced by 14% in NCL-SSL and by 4% in ALQ-CSL. Soil OC and dissolved OC were the parameters which explained pesticide residues in soil. Chemical analysis revealed that leachates from the different soil columns did not contain toxic element levels, except As in NCL soil. Finally ecotoxicological data showed moderate toxicity in the initial leachates, with an increase coinciding with pesticide maximum concentration. The addition of SSL slightly reduced the toxicity towards Vibrio fischeri, likely due to enhanced retention of pesticides by amended soils. PMID:25169870

Rodríguez-Liébana, José Antonio; Mingorance, M Dolores; Peña, Aránzazu

2014-11-01

128

Effect of washing treatments on pesticide residues and antioxidant compounds in Yuja ( Citrus junos Sieb ex Tanaka)  

Microsoft Academic Search

This study investigated the removal efficiency of pesticide residues and microorganisms, and changes of the amount of antioxidant\\u000a compounds on yuja (Citrus junos Sieb ex Tanaka) by various washing methods. The washing methods were mechanical washing (MW), mechanical washing after soaking\\u000a in SAcEW, strong acidic electrolyzed water (SAcEW+MW), and soaking detergent solution (DW), with a tap water washing (TW)\\u000a as

Jung-Min Sung; Ki-Hyun Kwon; Jong-Hoon Kim; Jin-Woong Jeong

2011-01-01

129

Effect of Endocrine Disruptor Pesticides: A Review  

PubMed Central

Endocrine disrupting chemicals (EDC) are compounds that alter the normal functioning of the endocrine system of both wildlife and humans. A huge number of chemicals have been identified as endocrine disruptors, among them several pesticides. Pesticides are used to kill unwanted organisms in crops, public areas, homes and gardens, and parasites in medicine. Human are exposed to pesticides due to their occupations or through dietary and environmental exposure (water, soil, air). For several years, there have been enquiries about the impact of environmental factors on the occurrence of human pathologies. This paper reviews the current knowledge of the potential impacts of endocrine disruptor pesticides on human health. PMID:21776230

Mnif, Wissem; Hassine, Aziza Ibn Hadj; Bouaziz, Aicha; Bartegi, Aghleb; Thomas, Olivier; Roig, Benoit

2011-01-01

130

Lysis of cyanobacteria with volatile organic compounds.  

PubMed

One of bacteria collected from Lake Sagami, Japan, Brevibacillus sp., was found to have a lytic activity of cyanobacteria, but did not produce active compounds. Instead, the co-culturing of Microcystis with the Brevibacillus sp. enhanced the production of two volatile compounds, beta-cyclocitral and 3-methyl-1-butanol, and the former had a characteristic lytic activity. It was confirmed that these volatile compounds were derived from the cyanobacteria themselves. beta-Ionone, geosmin and 2-methylisoborneol derived from cyanobacteria and similar volatile compounds, terpenoids, produced by plants also had a lytic activity. The minimum inhibitory concentration values of the cyanobacterial metabolites were estimated to be higher than those of compounds from plants except for a few compounds. Among them, beta-cyclocitral only produced a characteristic color change of culture broth from green to blue. This color change is similar to the phenomenon observed when a sudden decline in growth of cyanobacteria begins in a natural environment. PMID:18179811

Ozaki, Keiko; Ohta, Akemi; Iwata, Chieko; Horikawa, Aki; Tsuji, Kiyomi; Ito, Emiko; Ikai, Yoshitomo; Harada, Ken-Ichi

2008-04-01

131

High Arctic Biogenic Volatile Organic Compound emissions  

NASA Astrophysics Data System (ADS)

Biogenic volatile organic compounds (BVOCs) emitted from terrestrial vegetation participate in oxidative reactions, affecting the tropospheric ozone concentration and the lifetimes of greenhouse gasses such as methane. Also, they affect the formation of secondary organic aerosols. BVOCs thus provide a strong link between the terrestrial biosphere, the atmosphere and the climate. Global models of BVOC emissions have assumed minimal emissions from the high latitudes due to low temperatures, short growing seasons and sparse vegetation cover. However, measurements from this region of the world are lacking and emissions from the High Arctic have not been published yet. The aim of this study was to obtain the first estimates for BVOC emissions from the High Arctic. Hereby, we wish to add new knowledge to the understanding of global BVOC emissions. Measurements were conducted in NE Greenland (74°30' N, 20°30' W) in four vegetation communities in the study area. These four vegetation communities were dominated by Cassiope tetragona, Salix arctica, Vaccinium uliginosum and Kobresia myosuroides/Dryas octopetela/Salix arctica, respectively. Emissions were measured by enclosure technique and collection of volatiles into adsorbent cartridges in August 2009. The volatiles were analyzed by gas chromatography-mass spectrometry following thermal desorption. Isoprene showed highest emissions in S. arctica-dominated heath, where it was the dominant single BVOC. However, isoprene emission decreased below detection limit in the end of August when the temperature was at or below 10°C. According to a principal component analysis, monoterpene and sesquiterpene emissions were especially associated with C. tetragona-dominated heath. Especially S. arctica and C. tetragona dominated heaths showed distinct patterns of emitted BVOCs. Emissions of BVOC from the studied high arctic heaths were clearly lower than the emissions observed previously in subarctic heaths with more dense vegetation and higher ambient temperature. However, high arctic BVOC emissions are expected to increase in the future as a result of the predicted pronounced climate warming effects in the High Arctic. Therefore, we suggest that further studies should be conducted to investigate the effects of climate changes in the region in order to gain new knowledge and understanding of future global BVOC emissions.

Schollert, Michelle; Buchard, Sebrina; Faubert, Patrick; Michelsen, Anders; Rinnan, Riikka

2013-04-01

132

Adsorption study of low-cost and locally available organic substances and a soil to remove pesticides from aqueous solutions  

NASA Astrophysics Data System (ADS)

Sorption and desorption of chlorfenvinphos, chlorpyrifos, simazine and trifluralin on sunflower seed shells, rice husk, composted sewage sludge and an agricultural soil was studied. Film diffusion and sorption pointed to be related with pesticide physicochemical characteristics. Trifluralin and chlorpyrifos were the pesticides which showed the fastest sorption kinetics and the best sorption capacities when sorbed on all organic wastes. Rice husk revealed as the best adsorbent for simazine. Chlorfenvinphos showed comparable adsorption levels for all sorbents. Koc and Kf values suggested that not only the organic matter content but also the nature of the organic matter and other factors, such as physicochemical characteristics of the surface could be play a significant role in pesticide adsorption. Low desorption percentages were detected; nevertheless Kfd and H values reveal a weak and reversible adsorption. The studied organic residues can be used as an effective and alternative adsorbent for removing pesticides, because of their high adsorption capacity, being natural and economic.

Rojas, Raquel; Morillo, José; Usero, José; Vanderlinden, Eva; El Bakouri, Hicham

2015-01-01

133

CTEPP OVERVIEW: A PILOT STUDY OF CHILDREN'S TOTAL EXPOSURE TO PERSISTENT PESTICIDES AND OTHER PERSISTENT ORGANIC POLLUTANTS  

EPA Science Inventory

The research study, "Children's Total Exposure to Persistent Pesticides and Other Persistent Organic Pollutants," (CTEPP) is a pilot-scale project involving about 260 children in their everyday surroundings. The objectives of CTEPP are twofold: (1) To measure the agg...

134

REACTIVITY OF NITROGENOUS AND OTHER ORGANIC COMPOUNDS WITH AQUEOUS CHLORINE  

EPA Science Inventory

A protocol for determining the chlorine demand of organic compounds was developed and tested. Organics were reacted with chlorine at mole ratios of 1:05, 1:1, and 1:3 at pH values of 6, 7, and 8 over a one week period. Compounds tested were drawn mainly from the EPA Register of O...

135

A Systematic Presentation of Organic Phosphorus and Sulfur Compounds.  

ERIC Educational Resources Information Center

Because the names, interrelations, and oxidation levels of the organic compounds of phosphorus and sulfur tend to confuse students, a simple way to organize these compounds has been developed. The system consists of grouping them by oxidation state and extent of carbon substitution. (JN)

Hendrickson, James B.

1985-01-01

136

40 CFR 60.542 - Standards for volatile organic compounds.  

Code of Federal Regulations, 2011 CFR

... 2011-07-01 false Standards for volatile organic compounds. 60.542 Section 60.542 Protection of Environment...Manufacturing Industry § 60.542 Standards for volatile organic compounds. (a) On and after the date on which the initial...

2011-07-01

137

40 CFR 60.442 - Standard for volatile organic compounds.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Standard for volatile organic compounds. 60.442 Section 60.442 Protection of Environment...Coating Operations § 60.442 Standard for volatile organic compounds. (a) On and after the date on which the...

2011-07-01

138

40 CFR 60.452 - Standard for volatile organic compounds.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Standard for volatile organic compounds. 60.452 Section 60.452 Protection of Environment...Large Appliances § 60.452 Standard for volatile organic compounds. On or after the date on which the performance test...

2010-07-01

139

40 CFR 60.462 - Standards for volatile organic compounds.  

Code of Federal Regulations, 2011 CFR

... 2011-07-01 false Standards for volatile organic compounds. 60.462 Section 60.462 Protection of Environment...Surface Coating § 60.462 Standards for volatile organic compounds. (a) On and after the date on which § 60.8...

2011-07-01

140

40 CFR 60.452 - Standard for volatile organic compounds.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Standard for volatile organic compounds. 60.452 Section 60.452 Protection of Environment...Large Appliances § 60.452 Standard for volatile organic compounds. On or after the date on which the performance test...

2011-07-01

141

40 CFR 60.582 - Standard for volatile organic compounds.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Standard for volatile organic compounds. 60.582 Section 60.582 Protection of Environment...and Printing § 60.582 Standard for volatile organic compounds. (a) On and after the date on which the...

2011-07-01

142

40 CFR 60.432 - Standard for volatile organic compounds.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Standard for volatile organic compounds. 60.432 Section 60.432 Protection of Environment...Rotogravure Printing § 60.432 Standard for volatile organic compounds. During the period of the performance test required...

2010-07-01

143

40 CFR 60.442 - Standard for volatile organic compounds.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Standard for volatile organic compounds. 60.442 Section 60.442 Protection of Environment...Coating Operations § 60.442 Standard for volatile organic compounds. (a) On and after the date on which the...

2010-07-01

144

Organic Diets Significantly Lower Children’s Dietary Exposure to Organophosphorus Pesticides  

Microsoft Academic Search

We used a novel study design to measure dietary organophosphorus pesticide exposure in a group of 23 elementary school-age children through urinary biomonitoring. We substituted most of chil- dren's conventional diets with organic food items for 5 consecutive days and collected two spot daily urine samples, first-morning and before-bedtime voids, throughout the 15-day study period. We found that the median

Chensheng Lu; Kathryn Toepel; Rene Irish; Richard A. Fenske; Dana B. Barr; Roberto Bravo

2006-01-01

145

EPIDEMIOLOGY OF SUICIDES AMONG WORKERS EXPOSED OCCUPATIONALLY TO ELECTROMAGNETIC FIELDS, ORGANIC SOLVENTS AND PESTICIDES  

Microsoft Academic Search

Summary. We present an epidemiological study on a possible association between suicide and occupational exposure to electromagnetic fields, pesticides and organic solvents. A total of 7,512 deaths within the period 1994-2002 were analyzed. The assessment of occupational exposure was based on the job title reported in death certificates and medical protocols. The exposed group comprised 5,762 deaths (1,890 workers exposed

Aleksandra Arizanovi?

2004-01-01

146

FIELD SCREENING FOR HALOGENATED VOLATILE ORGANIC COMPOUNDS  

SciTech Connect

Western Research Institute (WRI) is continuing work toward the development of new screening methodology and a test kit to measure halogenated volatile organic compounds (VOCs) in the field. Heated diode and corona discharge sensors are commonly used to detect leaks of refrigerants from air conditioners, freezers, and refrigerators. They are both selective to the presence of halogens. In prior work, the devices were tested for response to carbon tetrachloride, heptane, toluene, and water vapors. In the current work, sensor response was evaluated with sixteen halogenated VOCs relative to carbon tetrachloride. The results show that the response of the various chlorinated VOCs is within an order of magnitude of the response to carbon tetrachloride for each of the sensors. Thus, for field screening a single response factor can be used. Both types of leak detectors are being further modified to provide an on-board LCD signal readout, which is related to VOC concentration. The units will be fully portable and will operate with 115-V line or battery power. Signal background, noise level, and response data on the Bacharach heated diode detector and the TIF corona discharge detector show that when the response curves are plotted against the log of concentration, the plot is linear to the upper limit for the particular unit, with some curvature at lower levels. When response is plotted directly against concentration, the response is linear at the low end and is curved at the high end. The dynamic ranges for carbon tetrachloride of the two devices from the lower detection limit (S/N=2) to signal saturation are 4-850 vapor parts per million (vppm) for the corona discharge unit and 0.01-70 vppm for the heated diode unit. Additional circuit modifications are being made to lower the detection limit and increase the dynamic response range of the corona discharge unit. The results indicate that both devices show potential utility for future analytical method development work toward the goal of developing a portable test kit for screening halogenated VOCs in the field.

John F. Schabron; Joseph F. Rovani, Jr.; Theresa M. Bomstad

2003-07-01

147

Interaction of organophosphate pesticides and related compounds with the androgen receptor.  

PubMed Central

Identification of several environmental chemicals capable of binding to the androgen receptor (AR) and interfering with its normal function has heightened concern about adverse effects across a broad spectrum of environmental chemicals. We previously demonstrated AR antagonist activity of the organophosphate (OP) pesticide fenitrothion. In this study, we characterized AR activity of analogues of fenitrothion to probe the structural requirements for AR activity among related chemicals. AR activity was measured using HepG2 human hepatoma cells transfected with human AR plus an androgen-responsive luciferase reporter gene, MMTV-luc. AR antagonist activity decreased as alkyl chain length of the phosphoester increased, whereas electron-donating properties of phenyl substituents of the tested compounds did not influence AR activity. Oxon derivatives of fenitrothion, which are more likely to undergo hydrolytic degradation, had no detectable AR antagonist activity. Molecular modeling results suggest that hydrogen-bond energies and the maximum achievable interatomic distance between two terminal H-bond capable sites may influence both the potential to interact with the AR and the nature of the interaction (agonist vs. antagonist) within this series of chemicals. This hypothesis is supported by the results of recent AR homology modeling and crystallographic studies relative to agonist- and antagonist-bound AR complexes. The present results are placed in the context of structure-activity knowledge derived from previous modeling studies as well as studies aimed toward designing nonsteroidal antiandrogen pharmaceuticals. Present results extend understanding of the structural requirements for AR activity to a new class of nonsteroidal, environmental, OP-related chemicals. PMID:12676613

Tamura, Hiroto; Yoshikawa, Hiromichi; Gaido, Kevin W; Ross, Susan M; DeLisle, Robert K; Welsh, William J; Richard, Ann M

2003-01-01

148

Sediment contamination of residential streams in the metropolitan Kansas City area, USA: Part I. Distribution of polycyclic aromatic hydrocarbon and pesticide-related compounds.  

PubMed

This is the first part of a study that evaluates the influence of nonpoint-source contaminants on the sediment quality of five streams within the metropolitan Kansas City area, central United States. Surficial sediment was collected in 2003 from 29 sites along five streams with watersheds that extend from the core of the metropolitan area to its development fringe. Sediment was analyzed for 16 polycyclic aromatic hydrocarbons (PAHs), 3 common polychlorinated biphenyl mixtures (Aroclors), and 25 pesticiderelated compounds of eight chemical classes. Multiple PAHs were detected at more than 50% of the sites, and concentrations of total PAHs ranged from 290 to 82,150 microg/kg (dry weight). The concentration and frequency of detection of PAHs increased with increasing urbanization of the residential watersheds. Four- and five-ring PAH compounds predominated the PAH composition (73-100%), especially fluoranthene and pyrene. The PAH composition profiles along with the diagnostic isomer ratios [e.g., anthracene/(anthracene + phenanthrene), 0.16 +/- 0.03; fluoranthene/(fluoranthene + pyrene), 0.55 +/- 0.01)] indicate that pyrogenic sources (i.e., coal-tar-related operations or materials and traffic-related particles) may be common PAH contributors to these residential streams. Historicaluse organochlorine insecticides and their degradates dominated the occurrences of pesticide-related compounds, with chlordane and dieldrin detected in over or nearly 50% of the samples. The occurrence of these historical organic compounds was associated with past urban applications, which may continue to be nonpoint sources replenishing local streams. Concentrations of low molecular weight (LMW; two or three rings) and high molecular weight (HMW; four to six rings) PAHs covaried along individual streams but showed dissimilar distribution patterns between the streams, while the historical pesticide-related compounds generally increased in concentration downstream. Correlations were noted between LMW and HMW PAHs for most of the streams and between historical-use organochlorine compounds and total organic carbon and clay content of sediments for one of the streams (Brush Creek). Stormwater runoff transport modes are proposed to describe how the two groups of contaminants migrated and distributed in the streambed. PMID:20390412

Tao, J; Huggins, D; Welker, G; Dias, J R; Ingersoll, C G; Murowchick, J B

2010-10-01

149

Distinct bioaccumulation profile of pesticides and dioxin-like compounds by mollusk bivalves reared in polluted and unpolluted tropical bays: consumption risk and seasonal effect.  

PubMed

Mariculture activity has increased its production along the Atlantic Coast of Brazil over the last years. This protein source for human consumption may also represent risks due to the exposure to bioaccumulated contaminants in the tissues of organisms reared in polluted shallow waters. This study evaluated the bioaccumulation of pesticides and dioxin-like compounds in two commercial marine bivalve species reared at different sites along the Rio de Janeiro State coast (SE-Brazil). We observed distinct contamination profiles in bivalve tissues reared at each sampling site, which may be related to human activities historically developed in those areas. A pronounced tendency for higher contamination levels in animals sampled in the last month of winter (September) is discussed as being likely due to environmental issues, rather than biological factors. Based on Minimal Risk Level, Maximum Residue, Acceptable Daily Intake and Toxic Equivalent, bivalves are classified as safe for human consumption. PMID:23442654

Galvao, Petrus; Henkelmann, Bernhard; Longo, Renan; Lailson-Brito, José; Torres, João Paulo Machado; Schramm, Karl-Werner; Malm, Olaf

2012-10-15

150

Quantifying commuter exposures to volatile organic compounds  

NASA Astrophysics Data System (ADS)

Motor-vehicles can be a predominant source of air pollution in cities. Traffic-related air pollution is often unavoidable for people who live in populous areas. Commuters may have high exposures to traffic-related air pollution as they are close to vehicle tailpipes. Volatile organic compounds (VOCs) are one class of air pollutants of concern because exposure to VOCs carries risk for adverse health effects. Specific VOCs of interest for this work include benzene, toluene, ethylbenzene, and xylenes (BTEX), which are often found in gasoline and combustion products. Although methods exist to measure time-integrated personal exposures to BTEX, there are few practical methods to measure a commuter's time-resolved BTEX exposure which could identify peak exposures that could be concealed with a time-integrated measurement. This study evaluated the ability of a photoionization detector (PID) to measure commuters' exposure to BTEX using Tenax TA samples as a reference and quantified the difference in BTEX exposure between cyclists and drivers with windows open and closed. To determine the suitability of two measurement methods (PID and Tenax TA) for use in this study, the precision, linearity, and limits of detection (LODs) for both the PID and Tenax TA measurement methods were determined in the laboratory with standard BTEX calibration gases. Volunteers commuted from their homes to their work places by cycling or driving while wearing a personal exposure backpack containing a collocated PID and Tenax TA sampler. Volunteers completed a survey and indicated if the windows in their vehicle were open or closed. Comparing pairs of exposure data from the Tenax TA and PID sampling methods determined the suitability of the PID to measure the BTEX exposures of commuters. The difference between BTEX exposures of cyclists and drivers with windows open and closed in Fort Collins was determined. Both the PID and Tenax TA measurement methods were precise and linear when evaluated in the laboratory using standard BTEX gases. The LODs for the Tenax TA sampling tubes (determined with a sample volume of 1,000 standard cubic centimeters which is close to the approximate commuter sample volumes collected) were orders of magnitude lower (0.04 to 0.7 parts per billion (ppb) for individual compounds of BTEX) compared to the PIDs' LODs (9.3 to 15 ppb of a BTEX mixture), which makes the Tenax TA sampling method more suitable to measure BTEX concentrations in the sub-parts per billion (ppb) range. PID and Tenax TA data for commuter exposures were inversely related. The concentrations of VOCs measured by the PID were substantially higher than BTEX concentrations measured by collocated Tenax TA samplers. The inverse trend and the large difference in magnitude between PID responses and Tenax TA BTEX measurements indicates the two methods may have been measuring different air pollutants that are negatively correlated. Drivers in Fort Collins, Colorado with closed windows experienced greater time-weighted average BTEX exposures than cyclists (p: 0.04). Commuter BTEX exposures measured in Fort Collins were lower than commuter exposures measured in prior studies that occurred in larger cities (Boston and Copenhagen). Although route and intake may affect a commuter's BTEX dose, these variables are outside of the scope of this study. Within the limitations of this study (including: small sample size, small representative area of Fort Collins, and respiration rates not taken into account), it appears health risks associated with traffic-induced BTEX exposures may be reduced by commuting via cycling instead of driving with windows closed and living in a less populous area that has less vehicle traffic. Although the PID did not reliably measure low-level commuter BTEX exposures, the Tenax TA sampling method did. The PID measured BTEX concentrations reliably in a controlled environment, at high concentrations (300-800 ppb), and in the absence of other air pollutants. In environments where there could be multiple chemicals present that may produce a PID signal (such a

Kayne, Ashleigh

151

Volatile organic compounds and some very volatile organic compounds in new and recently renovated buildings in Switzerland  

NASA Astrophysics Data System (ADS)

Indoor air in new of recently renovated buildings was analysed by using different sorbents and analytical methods. Increased values of total volatile organic compounds (TVOC) were found on Tenax TA (1.6-31.7 mg m -3). Compared to older buildings, the amount of oxygen-containing compounds (aldehydes, ketones, alcohols) especially was elevated. High hexanal concentrations were measured in a significant amount of the houses. Differences of compound patterns were found from building to building. Complaints about discomfort and negative health effects are expected due to volatile organic compounds (VOC) and very volatile organic compounds (VVOC), as well as from low natural ventilation rates in some newly occupied buildings. Odorous compounds (naphthalene, higher aldehydes and alcohols, capronic acid, etc.) were found mainly, but some irritants and suspected sensitizing agents were also found. At the present state of our investigation chemicals causing other known toxic effects do not seem to increase the toxic risk substantially.

Rothweiler, Heinz; Wäger, Patrick A.; Schlatter, Christian

152

MICROBIAL TRANSFORMATION KINETICS OF ORGANIC COMPOUNDS  

EPA Science Inventory

One process determining the fate of xenobiotics (organics not natural to a system) in environmental waters is bacterial transformation. Bacteria are one of the most metabolically active groups of organisms in the environment. They can degrade and derive energy from a variety of o...

153

Rationale for Selection of Pesticides, Herbicides, and Related Compounds from the Hanford SST/DST Waste Considered for Analysis in Support of the Regulatory DQO (Privatization)  

SciTech Connect

Regulated pesticides, herbicides, miticides, and fungicides were evaluated for their potential past and current use at the Hanford Site. The starting list of these compounds is based on regulatory analyte input lists discussed in the Regulatory DQO. Twelve pesticide, herbicide, miticide, and fungicide compounds are identified for analysis in the Hanford SST and DST waste in support of the Regulatory DQO. The compounds considered for additional analyses are non-detected, considered stable in the tank waste matrix, and of higher toxicity/carcinogenicity.

Wiemers, K.D.; Daling, P.; Meier, K.

1999-01-04

154

Applying pesticides  

NSDL National Science Digital Library

Fertilizer is one way to provide crops with the nutrients they need. Pesticides can also be applied to crops to keep them healthy and free of insects. However, applying too much fertilizer or pesticide protection could harm the environment and organisms.

Scott Bauer (USDA-ARS; Yakima Agricultural Research Laboratory)

2006-05-23

155

Estimating pesticide sampling rates by the polar organic chemical integrative sampler (POCIS) in the presence of natural organic matter and varying hydrodynamic conditions  

USGS Publications Warehouse

The polar organic chemical integrative sampler (POCIS) was calibrated to monitor pesticides in water under controlled laboratory conditions. The effect of natural organic matter (NOM) on the sampling rates (Rs) was evaluated in microcosms containing -1 of total organic carbon (TOC). The effect of hydrodynamics was studied by comparing Rs values measured in stirred (SBE) and quiescent (QBE) batch experiments and a flow-through system (FTS). The level of NOM in the water used in these experiments had no effect on the magnitude of the pesticide sampling rates (p > 0.05). However, flow velocity and turbulence significantly increased the sampling rates of the pesticides in the FTS and SBE compared to the QBE (p < 0.001). The calibration data generated can be used to derive pesticide concentrations in water from POCIS deployed in stagnant and turbulent environmental systems without correction for NOM.

Charlestra, Lucner; Amirbahman, Aria; Courtemanch, David L.; Alvarez, David A.; Patterson, Howard

2012-01-01

156

Enantiomeric and Isotopic Analysis of Organic Compounds in Carbonaceous Meteorites  

NASA Technical Reports Server (NTRS)

Carbonaceous meteorites are relatively enriched in soluble organic compounds. The Murchison and Murray meteorites contain numerous compounds of interest in the study of early solar system organic chemistry and organic compounds of potential importance for the origin of life. These include: amino acids, amides, carboxylic acids, and polyols. This talk will focus on the enantiomeric and isotopic analysis of individual meteoritic compounds - primarily polyol acids. The analyses will determine if, in addition to certain amino acids from Murchison, another potentially important class of prebiotic compounds also contains enantiomeric excesses, i.e., excesses that could have contributed to the current homochirality of life. Preliminary enantiomeric and isotopic (C- 13) measurements of Murchison glyceric acid show that it is indeed extraterrestrial. C-13 and D isotope analysis of meteoritic sugar alcohols (glycerol, threitol, ribitol, etc.) has shown that they are also indigenous to the meteorite.

Cooper, George

2004-01-01

157

Evaluation of persistent hydrophobic organic compounds in the Columbia River Basin using semipermeable-membrane devices  

USGS Publications Warehouse

Persistent hydrophobic organic compounds are of concern in the Columbia River because they have been correlated with adverse effects on wildlife. We analysed samples from nine main-stem and six tributary sites throughout the Columbia River Basin (Washington and Oregon) for polychlorinated dibenzo-p-dioxins, dibenzofurans, polychlorinated biphenyls, organochlorine pesticides, and priority-pollutant polycyclic aromatic hydrocarbons. Because these compounds may have important biological consequences at aqueous concentrations well below the detection limits associated with conventional sampling methods, we used semipermeable-membrane devices to sample water and achieved parts-per-quintillion detection limits. All of these compound classes were prevalent within the basin, but concentrations of many analytes were highest in the vicinity of Portland-Vancouver, indicating that the Willamette subbasin-and perhaps the urban area in particular-is an important source of these compounds. Data collected during basin low-flow conditions in 1997 and again during basin high-flow conditions in 1998 indicate that in-stream processes such as dilution by relatively clean inflow, and flow through island hyporheic zones may be important mechanisms for attenuating dissolved concentrations of hydrophobic compounds.

McCarthy, K.A.; Gale, R.W.

2001-01-01

158

GLOBAL INVENTORY OF VOLATILE ORGANIC COMPOUND EMISSIONS FROM ANTHROPOGENIC SOURCES  

EPA Science Inventory

The paper discusses the development of a global inventory of anthropogenic volatile organic compound (VOC) emissions. t includes VOC estimates for seven classes of VOCs: paraffins, olefins, aromatics (benzene, toluene, xylene), formaldehyde, other aldehydes, other aromatics, and ...

159

40 CFR 60.462 - Standards for volatile organic compounds.  

Code of Federal Regulations, 2010 CFR

...CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Metal Coil Surface Coating § 60.462 Standards for volatile organic compounds. (a) On and after the date on which §...

2010-07-01

160

SEPARATION OF VOLATILE ORGANIC COMPOUNDS FROM SURFACTANT SOLUTIONS BY PERVAPORATION  

EPA Science Inventory

Pervaporation is gradually becoming an accepted and practical method for the recovery of volatile organic compounds (VOCs) from aqueous process and waste streams. As the technolog has matured, new applications for pervaporation have emerged. One such application is the separati...

161

40 CFR 60.582 - Standard for volatile organic compounds.  

Code of Federal Regulations, 2010 CFR

... STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Flexible Vinyl and Urethane Coating and Printing § 60.582 Standard for volatile organic compounds. (a) On and after the date on which the performance test...

2010-07-01

162

40 CFR 60.432 - Standard for volatile organic compounds.  

Code of Federal Regulations, 2011 CFR

...OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for the Graphic Arts Industry: Publication Rotogravure Printing § 60.432 Standard for volatile organic compounds. During the period of the performance test required to be...

2011-07-01

163

40 CFR 60.432 - Standard for volatile organic compounds.  

...OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for the Graphic Arts Industry: Publication Rotogravure Printing § 60.432 Standard for volatile organic compounds. During the period of the performance test required to be...

2014-07-01

164

40 CFR 60.432 - Standard for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for the Graphic Arts Industry: Publication Rotogravure Printing § 60.432 Standard for volatile organic compounds. During the period of the performance test required to be...

2013-07-01

165

40 CFR 60.392 - Standards for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Automobile and Light Duty Truck Surface Coating Operations § 60.392 Standards for volatile organic compounds. On and...

2013-07-01

166

SYNTHESIZING ORGANIC COMPOUNDS USING LIGHT-ACTIVATED TIO2  

EPA Science Inventory

High-value organic compounds have been synthesized successfully from linear and cyclic hydrocarbons, by photocatalytic oxidation using a semiconductor material, titanium dioxide (TiO2). Various hydrocarbons were partially oxgenated in both liquid and gaseous phase reactors usi...

167

ESTIMATION OF PHYSIOCHEMICAL PROPERTIES OF ORGANIC COMPOUNDS BY SPARC  

EPA Science Inventory

The computer program SPARC (SPARC Performs Automated Reasoning in Chemistry) has been under development for several years to estimate physical properties and chemical reactivity parameters of organic compounds strictly from molecular structure. SPARC uses computational algorithms...

168

40 CFR 60.392 - Standards for volatile organic compounds.  

...CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Automobile and Light Duty Truck Surface Coating Operations § 60.392 Standards for volatile organic compounds. On and...

2014-07-01

169

IMPROVEMENT IN AIR TOXICS METHODS FOR VOLATILE ORGANIC COMPOUNDS  

EPA Science Inventory

Innovative and customized monitoring methods for air toxic volatile organic compounds (VOCs) are being developed for applications in exposure and trends monitoring. This task addresses the following applications of specific interest: o Contributions to EPA Regional Monit...

170

VOCs, Pesticides, Nitrate, and Their Mixtures in Groundwater Used for  

E-print Network

of intensive current research. The effects of multicontaminant exposure on humans are uncertain, and additionalVOCs, Pesticides, Nitrate, and Their Mixtures in Groundwater Used for Drinking Water in the United areas. For each sample, as many as 60 volatile organic compounds (VOCs), 83 pesticides, and nitrate were

171

CHARACTERIZATION OF VOLATILE ORGANIC COMPOUNDS IN AIRBORNE DUST  

Technology Transfer Automated Retrieval System (TEKTRAN)

Three methods of extracting volatile organic compounds (VOC's) adsorbed on the airborne dust in a swine finishing building were investigated. Airborne dust was collected in pre-baked glass fiber filters (GFF's) and the compounds were extracted by solvent extraction using dichloromethane, solid phas...

172

INDOOR AIR QUALITY DATA BASE FOR ORGANIC COMPOUNDS  

EPA Science Inventory

The report gives results of the compilation of a data base for concentrations of organic compounds measured indoors. ased on a review of the literature from 1979 through 1990, the data base contains information on over 220 compounds ranging in molecular weight from 30 to 446. he ...

173

Sorption Dynamics of Organic and Inorganic Phosphorus Compounds in Soil  

Microsoft Academic Search

Phosphorus retention in soils is influenced by the form of P added. The potential impact of one P compound on the sorption of other P compounds in soils has not been widely reported. Sorption isotherms were utilized to quantify P retention by benchmark soils from Indiana, Missouri, and North Carolina when P was added as inorganic P (Pi) or organic

A. S. Berg; B. C. Joern

2006-01-01

174

Current Status and Regulatory Aspects of Pesticides Considered to be Persistent Organic Pollutants (POPs) in Taiwan  

PubMed Central

Organochlorine pesticides (OCPs) are capable of persisting in the environment, transporting between phase media and accumulating to high levels, implying that they could pose a risk of causing adverse effects to human health and the environment. Consequently, most OCPs are designated as persistent organic pollutants (POPs) and even as endocrine disrupting chemicals (EDCs). The objective of this paper was to review the current status of pesticide POPs in Taiwan, including aldrin, chlordane, chlordecone, DDT, dieldrin, endrin, heptachlor, hexachlorobenzene, ?/?-hexachlorocyclohexanes, lindane, mirex, pentachloro-benzene, and toxaphene. The information about their environmental properties, banned use, carcinogenic toxicity and environmental levels, can be connected with the regulatory infrastructure, which has been established by the joint-venture of the central competent authorities (i.e., Environmental Protection Administration, Department of Health, Council of Agriculture, and Council of Labor Affairs). The significant progress to be reported is that the residual levels of these pesticide-POPs, ranging from trace amounts to a few ppb, have declined notably in recent years. PMID:21139852

Tsai, Wen-Tien

2010-01-01

175

Process for reducing organic compounds with calcium, amine, and alcohol  

DOEpatents

Olefins are produced by contacting an organic compound having at least one benzene ring with calcium metal, ethylenediamine, a low molecular weight aliphatic alcohol, and optionally a low molecular weight aliphatic primary amine, and/or an inert, abrasive particulate substance. The reduction is conducted at temperatures ranging from about [minus]10 C to about 30 C or somewhat higher. Substantially all of the organic compounds are converted to corresponding cyclic olefins, primarily diolefins.

Benkeser, R.A.; Laugal, J.A.; Rappa, A.

1985-08-06

176

Scientists Probe Pesticide Dynamics  

ERIC Educational Resources Information Center

Summarizes discussions of a symposium on pesticide environmental dynamics with emphases upon pesticide transport processes, environmental reactions, and partitioning in air, soil, water and living organisms. Indicates that the goal is to attain knowledge enough to predict pesticide behavior and describe pesticide distribution with models and…

Chemical and Engineering News, 1974

1974-01-01

177

Transport, behavior, and fate of volatile organic compounds in streams  

USGS Publications Warehouse

Volatile organic compounds (VOCs) are compounds with chemical and physical properties that allow the compounds to move freely between the water and air phases of the environment. VOCs are widespread in the environment because of this mobility. Many VOCs have properties making them suspected or known hazards to the health of humans and aquatic organisms. Consequently, understanding the processes affecting the concentration and distribution VOCs in the environment is necessary. The U.S. Geological Survey selected 55 VOCs for study. This report reviews the characteristics of the various process that could affect the transport, behavior, and fate of these VOCs in streams.

Rathbun, R.E.

1998-01-01

178

Volatile Organic Compound Detection Using Nanostructured Copolymers  

E-print Network

such as SnO2 and ZnO, have been widely used in commercial chemical vapor sensors. A big drawback crystalline nanostructures are shown to hold considerable promise as the active layer in volatile organic tested analytes. Conductive polymers with alternating single and double carbon-carbon bonds have recently

Weiss, Lee E.

179

Analysis of volatile organic compounds from illicit cocaine samples  

SciTech Connect

Detection of illicit cocaine hydrochloride shipments can be improved if there is a greater understanding of the identity and quantity of volatile compounds present. This study provides preliminary data concerning the volatile organic compounds detected in a limited Set of cocaine hydrochloride samples. In all cases, cocaine was one of the major volatile compounds detected. Other tropeines were detected in almost all samples. Low concentrations of compounds that may be residues of processing solvents were observed in some samples. The equilibrium emissivity of. cocaine from cocaine hydrochloride was investigated and a value of 83 parts-per-trillion was determined.

Robins, W.H.; Wright, B.W.

1994-07-01

180

MANUAL OF ANALYTICAL QUALITY CONTROL FOR PESTICIDES AND RELATED COMPOUNDS IN HUMAN AND ENVIRONMENTAL SAMPLES  

EPA Science Inventory

This manual provides the pesticide chemist with a systematic protocol for the quality control of analytical procedures and the problems that arise in the analysis of human or environmental media. It also serves as a guide to the latest and most reliable methodology available for ...

181

Prevention of marine biofouling using natural compounds from marine organisms.  

PubMed

All surfaces that are submerged in the sea rapidly become covered by a biofilm. This process, called biofouling, has substantial economic consequences. Paints containing tri-butyl-tin (TBT) and copper compounds are used to protect marine structures by reducing biofouling. However, these compounds have damaging effects on the marine environment, as they are not biodegradable. It has been noted that many seaweeds and invertebrates found in the sea are not covered by a mature biofilm. This is due to the release of compounds into the surrounding seawater that deter the settlement of fouling organisms. In addition, seaweeds and invertebrates have bacteria on their surfaces that produce compounds to deter settling organisms. The production of compounds by bacteria and their living hosts work in concert to protect the hosts' surfaces. All of these compounds can be collected so they may be natural alternatives to TBT and copper compounds. However, the benefits associated with the use of bacteria as sources of these compounds means that bacteria are the organisms of choice for obtaining natural products for antifouling coatings. PMID:11193296

Armstrong, E; Boyd, K G; Burgess, J G

2000-01-01

182

Chiral pesticides: identification, description, and environmental implications.  

PubMed

Of the 1,693 pesticides considered in this review, 1,594 are organic chemicals, 47 are inorganic chemicals, 53 are of biological origin (largely non chemical; insect,fungus, bacteria, virus, etc.), and 2 have an undetermined structure. Considering that the EPA's Office of Pesticide Programs found 1,252 pesticide active ingredients(EPA Pesticides Customer Service 2011), we consider this dataset to be comprehensive; however, no direct comparison of the compound lists was undertaken. Of all pesticides reviewed, 482 (28%) are chiral; 30% are chiral when considering only the organic chemical pesticides. A graph of this distribution is shown in Fig. 7a. Each pesticide is classified with up to three pesticidal utilities (e.g., fungicide, plant growth regulator, rodenticide, etc.), taken first from the Pesticide Manual as a primary source, and the Compendium of Common Pesticide Names website as a secondary source. Of the chiral pesticides, 195 (34%) are insecticides (including attractants, pheromones, and repellents), 150 (27%) are herbicides (including plant growth regulators and herbicide safeners), 104 (18%) are fungicides, and 55 (10%)are acaricides. The distribution of chiral pesticides by utility is shown in Fig. 7b,including categories of pesticides that make up 3%t or less of the usage categories.Figure 7c shows a similar distribution of non chiral pesticide usage categories. Of the chiral pesticides, 270 (56%) have one chiral feature, 105 (22%) have two chiral features, 30 (6.2%) have three chiral features, and 29 (6.0%) have ten or more chiral features.Chiral chemicals pose many difficulties in stereospecific synthesis, characterization, and analysis. When these compounds are purposely put into the environment,even more interesting complications arise in tracking, monitoring, and predicting their fate and risks. More than 475 pesticides are chiral, as are other chiral contaminants such as pharmaceuticals, polychlorinated biphenyls, brominated flame retardants, synthetic musks, and their degradates (Kallenborn and Hiihnerfuss 2001;Heeb et al. 2007; Hihnerfuss and Shah 2009). The stereoisomers of pesticides can have widely different efficacy, toxicity to nontarget organisms, and metabolic rates in biota. For these reasons, it is important to first be aware of likely fate and effect differences, to incorporate molecular asymmetry insights into research projects, and to study the individual stereoisomers of the applied pesticide material.With the advent of enantioselective chromatography techniques, the chirality of pesticides has been increasingly studied. While the ChirBase (Advanced ChemistryDevelopment 1997-2010) database does not include all published chiral analytical separations, it does contain more than 3,500 records for 146 of the 482 chiral pesticides (30%). The majority of the records are found in the liquid chromatography database (2,677 or 76%), followed by the gas chromatography database (652 or 18%),and the capillary electrophoresis database (203 or 6%). The finding that only 30% of the chiral pesticides covered in this review have entries in ChirBase highlights the need for expanded efforts to develop additional enantioselective chromatographic methods. Other techniques (e.g., nuclear magnetic resonance and other spectroscopy)are available for investigation of chiral compounds, but often are not utilized because of cost, complexity, or simply not recognizing that a pesticide is chiral.In this review, we have listed and have briefly described the general nature of chiral fungicides, herbicides, insecticides, and other miscellaneous classes. A data-set generated for this review contains 1,693 pesticides, the number of enantioselective separation records in ChirBase, pesticide usage class, SMILES structure string and counts of stereogenic centers. This dataset is publically available for download at the following website: http://www.epa.gov/heasd/products/products.html. With the information herein coupled to the publically accessible dataset, we can begin to develop the tools to handle molecular asymmetry as

Ulrich, Elin M; Morrison, Candice N; Goldsmith, Michael R; Foreman, William T

2012-01-01

183

Anthropogenic Organic Compounds in Ground Water and Finished Water of Community Water Systems in the Greater Twin Cities Metropolitan Area, Minnesota and Wisconsin, 2004-05  

USGS Publications Warehouse

As part of the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program, two Source Water-Quality Assessments (SWQAs) were conducted during 2004-05 in unconfined parts of the glacial aquifer system and in unconfined parts of the Prairie du Chien-Jordan aquifer in the Greater Twin Cities metropolitan area of Minnesota and Wisconsin. SWQAs are two-phased sampling activities in the NAWQA Program. The first phase evaluated the occurrence of 265 (258 are included in this report) anthropogenic organic compounds (AOCs) through monitoring source water in 30 of the largest-producing community water system wells completed in the aquifers underlying the Greater Twin Cities metropolitan area. The AOCs included volatile organic compounds (VOCs), pesticides, and other AOCs. During the second phase of the study, 15 of the original community water system wells, those with the greatest number of AOC detections, were resampled along with associated finished water. Results from the first phase of sampling indicated that 40 AOCs were detected, and 83 percent of the samples had at least one detected AOC. Concentrations of AOCs detected in the source water generally were low (defined in this report as concentrations less than 1.0 microgram per liter). Human-health benchmarks for these compounds (Maximum Contaminant Levels for regulated compounds or Health-Based Screening Levels for unregulated compounds, when they existed) typically were not exceeded. Fifteen VOCs were detected in the source-water samples. However, concentrations were low. Seventeen pesticide compounds were detected generally at concentrations less than concentrations for VOCs. Most of the pesticide compounds detected were triazine- or alachlor-parent compounds or their breakdown products. Eight other AOCs were detected in the source-water samples but generally at low concentrations. Results from the second phase of sampling indicated a total of 13 and 12 VOCs were detected in source-water and in finished-water samples, respectively. Most of the VOCs, except for those associated with disinfection by-products, were detected more frequently in source-water samples than in finished- water samples. Concentrations of most VOCs detected in either source water or finished water were less than human-health benchmarks. Twenty-one pesticide compounds were detected in either source water or finished water. Concentrations of detected pesticides in source-water and finished-water samples were low. The most frequently detected compounds in both the source and finished water were triazine-parent pesticides or their breakdown products and breakdown products of alachlor and metolachlor. In general, pesticides, if detected in source water, also were detected in the corresponding finished water. Concentrations of pesticides detected were less than human-health benchmarks in both source and finished water. A total of nine other AOCs were detected in the source-water or finished-water samples, and about the same number of compounds was detected in each of the sample groups in either source water or finished water. Detected concentrations of other AOCs were low. Water-quality results from source-water samples were compared to characterize differences between aquifers. VOC and other AOC detections were more frequent in water from the Prairie du Chien-Jordan aquifer compared to the glacial aquifer. Pesticides, however, were detected more frequently in the glacial aquifer. On the basis of study results, the hydrogeologic setting, land use, and aquifer productivity are important in explaining the occurrence of AOCs in community water system wells. Results of this study indicate that monitoring for pesticides in source water generally indicates the potential occurrence of pesticides in finished water but that this is not necessarily true of VOCs. Additional monitoring is needed to better understand the occurrence of other AOCs in source and finished waters.

Tornes, Lan H.; Stark, James R.; Hoard, Christopher J.; Smith, Erik A.

2007-01-01

184

40 CFR 60.502 - Standard for Volatile Organic Compound (VOC) emissions from bulk gasoline terminals.  

Code of Federal Regulations, 2011 CFR

...false Standard for Volatile Organic Compound (VOC) emissions from bulk gasoline...502 Standard for Volatile Organic Compound (VOC) emissions from bulk gasoline...designed to collect the total organic compounds vapors displaced from tank trucks...

2011-07-01

185

BIOCONCENTRATION FACTORS FOR VOLATILE ORGANIC COMPOUNDS IN VEGETATION  

EPA Science Inventory

Samples of air and leaves were taken at the University of Nevada-Las Vegas campus and analyzed for volatile organic compounds using vacuum distillation coupled with gas chromatography/mass spectrometry. The data were used to estimate the bioconcentration of volatile organic compo...

186

IDENTIFICATION OF ORGANIC COMPOUNDS IN INDUSTRIAL EFFLUENT DISCHARGES  

EPA Science Inventory

Samples of 63 effluent and 22 intake waters were collected from a wide range of chemical manufacturers in areas across the United States. The samples were analyzed for organic compounds in an effort to identify previously unknown and potentially hazardous organic pollutants. Each...

187

COMPARISON OF AMBIENT AIR SAMPLING TECHNIQUES FOR VOLATILE ORGANIC COMPOUNDS  

EPA Science Inventory

A series of fourteen experimental sampling runs were carried out at a field site to collect data from several ambient air monitoring methods for volatile organic compounds (VOCs). Ambient air was drawn through a sampling manifold and was continuously spiked with volatile organic ...

188

Students' Understanding of Molecular Structure and Properties of Organic Compounds.  

ERIC Educational Resources Information Center

The purpose of this study was to investigate senior high school students' difficulties predicting the existence of hydrogen bridge bonds between organic molecules, investigate students' difficulties predicting the relative boiling points of simple organic compounds, and develop test questions that enable teachers to quickly get information about…

Schmidt, Hans-Jurgen

189

Highly stable meteoritic organic compounds as markers of asteroidal delivery  

NASA Astrophysics Data System (ADS)

Multiple missions to search for water-soluble organic compounds on the surfaces of Solar System bodies are either current or planned and, if such compounds were found, it would be desirable to determine their origin(s). Asteroid or comet material is likely to have been components of all surface environments throughout Solar System history. To simulate the survival of meteoritic compounds both during impacts with planetary surfaces and under subsequent (possibly) harsh ambient conditions, we subjected known meteoritic compounds to comparatively high impact-shock pressures (>30 GPa) and/or to extremely oxidizing/corrosive acid solution. Consistent with past impact experiments, ?-amino acids survived only at trace levels above ?18 GPa. Polyaromatic hydrocarbons (PAHs) survived at levels of 4-8% at a shock pressure of 36 GPa. Lower molecular weight sulfonic and phosphonic acids (S&P) had the highest degree of impact survival of all tested compounds at higher pressures. Oxidation of compounds was done with a 3:1 mixture of HCl:HNO3, a solution that generates additional strong oxidants such as Cl2 and NOCl. Upon oxidation, keto acids and ?-amino acids were the most labile compounds with proline as a significant exception. Some fraction of the other compounds, including non-? amino acids and dicarboxylic acids, were stable during 16-18 hours of oxidation. However, S&P quantitatively survived several months (at least) under the same conditions. Such results begin to build a profile of the more robust meteoritic compounds: those that may have survived, i.e., may be found in, the more hostile Solar System environments. In the search for organic compounds, one current mission, NASA's Mars Science Laboratory (MSL), will use analytical procedures similar to those of this study and those employed previously on Earth to identify many of the compounds described in this work. The current results may thus prove to be directly relevant to potential findings of MSL and other missions designed for extraterrestrial organic analysis.

Cooper, George; Horz, Friedrich; Spees, Alanna; Chang, Sherwood

2014-01-01

190

Can volatile organic compounds be markers of sea salt?  

PubMed

Sea salt is a handmade food product that is obtained by evaporation of seawater in saltpans. During the crystallisation process, organic compounds from surroundings can be incorporated into sea salt crystals. The aim of this study is to search for potential volatile markers of sea salt. Thus, sea salts from seven north-east Atlantic Ocean locations (France, Portugal, Continental Spain, Canary Islands, and Cape Verde) were analysed by headspace solid-phase microextraction combined with comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry. A total of 165 compounds were detected, ranging from 32 to 71 compounds per salt. The volatile composition revealed the variability and individuality of each salt, and a set of ten compounds were detected in all samples. From these, seven are carotenoid-derived compounds that can be associated with the typical natural surroundings of ocean hypersaline environment. These ten compounds are proposed as potential volatile markers of sea salt. PMID:25236204

Silva, Isabel; Coimbra, Manuel A; Barros, António S; Marriott, Philip J; Rocha, Sílvia M

2015-02-15

191

Semivolatile organic compounds in indoor air and settled dust in 30 French dwellings.  

PubMed

Semivolatile organic compounds (SVOCs) are ubiquitous contaminants in indoor environments, emanating from different sources and partitioning among several compartments, including the gas phase, airborne particles, and settled dust. Nevertheless, simultaneous measurements in the three compartments are rarely reported. In this study, we investigated indoor concentrations of a wide range of SVOCs in 30 French dwellings. In settled dust, 40 out of 57 target compounds were detected. The highest median concentrations were measured for phthalates and to a lesser extent for bisphenol A, synthetic musks, some pesticides, and PAHs. Di(2-ethylhexyl)phthalate (DEHP) and diisononyl phthalate (DINP) were the most abundant compounds. A total of 34 target compounds were detected both in the gas phase and airborne particles. The highest concentrations were measured for diisobutyl phthalate (DiBP), diethyl phthalate (DEP), dibutyl phthalate (DBP), and synthetic musks in the gas phase and for DEHP, DiBP, DBP, and DINP in the airborne particles. This is the first study on the indoor concentrations of a wide range of SVOCs in settled dust, gas phase, and airborne particles collected simultaneously in each dwelling. PMID:24588211

Blanchard, Olivier; Glorennec, Philippe; Mercier, Fabien; Bonvallot, Nathalie; Chevrier, Cécile; Ramalho, Olivier; Mandin, Corinne; Bot, Barbara Le

2014-04-01

192

Polar Organic Compounds in Surface Waters Collected Near Lead-Zinc Mine and Milling Operations in Missouri  

NASA Astrophysics Data System (ADS)

Surface-water samples were collected near a lead mine and mill tailings about 70 miles southwest of St. Louis, Missouri, during the summer of 2006. The purpose of this sampling was to determine if polar organic compounds were present that could be a cause of documented negative impacts to biota downstream. Water samples contained relatively high concentrations of dissolved organic carbon for surface waters (greater than 20 mg/L), but were colorless, which precluded naturally occurring aquatic humic or fulvic acids. Previous analysis indicated that samples were devoid of pesticides and acid/base/neutral extractable semi-volatile organic compounds, such as polycyclic aromatic hydrocarbons. After isolation by three different types of solid phase extraction, samples were analyzed by electrospray ionization/mass spectrometry. Polar organic compounds commonly used in the milling process, such as alkyl xanthates, were not found; however, xanthate degradation products were detected. Most of the polar organic compounds identified contained sulfonate groups, which are characteristic of some of the reagents used in the milling process. Sulfonate compounds may have low sorption onto soil or sediments and be mobile in the aqueous environment.

Rostad, C. E.; Schmitt, C. J.; Schumacher, J. G.; Leiker, T. J.

2007-12-01

193

Measurements of bromine containing organic compounds at the tropical tropopause  

Microsoft Academic Search

The amount of bromine entering the stratosphere from organic source gases is a primary factor involved in determining the magnitude of bromine catalyzed loss of ozone. Thirty two whole air samples were collected at the tropical tropopause during the NASA STRAT Campaign in Feb., Aug., and Dec., 1996 and were analyzed for brominated organic compounds. Total organic bromine was 17.4+\\/-0.9ppt

S. M. Schauffler; E. L. Atlas; F. Flocke; R. A. Lueb; V. Stroud; W. Travnicek

1998-01-01

194

Determination of pesticide residues and related compounds in water and industrial effluent by solid-phase extraction and gas chromatography coupled to triple quadrupole mass spectrometry.  

PubMed

Pollution of drinking water supplies from industrial waste is a result of several industrial processes and disposal practices, and the establishment of analytical methods for monitoring organic compounds related to environmental and health problems is very important. In this work, a method using solid-phase extraction (SPE) and gas chromatography coupled to triple quadrupole tandem mass spectrometry (GC-QqQ-MS/MS) was developed and validated for the simultaneous determination of pesticide residues and related compounds in drinking and surface water as well as in industrial effluent. Optimization of the method was achieved by using a central composite design approach on parameters such as the sample pH and SPE eluent composition. A single SPE consisting of the loading on a polymeric sorbent of 100 mL of sample adjusted to pH 3 and elution with methanol/methylene chloride (10:90, v/v) permitted the obtaining of acceptable recoveries in most cases. The concentration factor associated with sensitivity of the chromatographic analysis permitted the achievement of the method limit of detection values between 0.01 and 0.25 ?g L(-1). Recovery assays presented mean recoveries between 70 and 120% for most of the compounds with very good precision, despite the different chemical nature of the compounds analyzed. The selectivity of the method, evaluated through the relative intensity of quantification and qualification ions obtained by GC-QqQ-MS/MS, was considered adequate. The developed method was finally applied to the determination of target analytes in real samples. River water and treated industrial effluent samples presented residues of some compounds, but no detectable residues were found in the drinking water samples evaluated. PMID:23995504

Martins, Manoel L; Donato, Filipe F; Prestes, Osmar D; Adaime, Martha B; Zanella, Renato

2013-09-01

195

Geosynthesis of organic compounds: I. Alkylphenols  

NASA Astrophysics Data System (ADS)

Methylation, isopropylation, and sec-butylation are proposed as geosynthetic processes to account for the alkylphenol compositions of crude oils with phenol distributions dominated by ortho and para substituted compounds. Phenol distributions in eleven crude oils and four kerogen pyrolysates were analysed using GC-MS (gas chromatography-mass spectrometry). Ten of the crude oils show high relative abundances of ortho and para substituted phenol isomers and some were also enriched in C 3-C 5 alkylphenols compared to the kerogen pyrolysates. Because the distributions of products obtained from the laboratory alkylation of cresols closely resemble those of phenols in these crude oils, we propose that similar alkylation processes occur in source rocks. Alkylation ratios reflecting the degree of methylation, isopropylation, and sec-butylation, which were based on the relative abundance of the dominant alkylation products compared to their likely precursor ortho-cresol, indicate that high levels of methylation occurred in crude oils over a wide range of maturities, whereas high levels of isopropylation and sec-butylation were observed only in mature samples. Dissolution of the phenols in crude oils by water contact was discounted as an explanation for the observed phenol distributions based on the relative distribution coefficients of phenols between a hydrocarbon phase and water.

Ioppolo-Armanios, Marisa; Alexander, Robert; Kagi, Robert I.

1995-07-01

196

Emission of volatile organic compounds to the atmosphere in the solvent sublation process. II. Volatile chlorinated organic compounds  

SciTech Connect

The mass of trichloroethylene, chlorobenzene, and 1,3-dichlorobenzene removed from an aqueous solution and emitted to the atmosphere during solvent sublation was determined experimentally. It was shown that the emission of these compounds in solvent sublation was reduced by 30 to 85% over air stripping under the same experimental conditions. The efficiency of removal of these compounds from water was also studied. The reduction of emissions over air stripping was more effective for the more hydrophobic and less volatile compounds. Emissions are reduced as the thickness of organic layer on the top of the column is increased. The use of decyl alcohol as the layer compound decreases emissions to a greater extent than does paraffin oil. Removal of these chlorinated volatile organic compounds from water by solvent sublation at an elevated temperature of 45{degrees}C is significantly faster than at room temperature. However, the emissions to the atmosphere are also increased.

Ososkov, V.; Kebbekus, B.; Chou, C.C. [New Jersey Inst. of Technology, Newark, NJ (United States)

1996-06-01

197

STUDIES OF PRESCHOOL CHILDREN'S EXPOSURES TO PESTICIDES  

EPA Science Inventory

Young children, especially those of the preschool ages, are hypothesized to have greater exposures than do older children or adults to persistent organic pesticides and other persistent organic pollutants, including some compounds that may have endocrine-disrupting effects or d...

198

GROUNDWATER TRANSPORT OF HYDROPHOBIC ORGANIC COMPOUNDS IN THE PRESENCE OF DISSOLVED ORGANIC MATTER  

EPA Science Inventory

The effects of dissolved organic matter (DOM) on the transport of hydrophobic organic compounds in soil columns were investigated. Three compounds (naphthalene, phenanthrene and DDT) that spanned three orders of magnitude in water solubility were used. Instead of humic matter, mo...

199

GROUND WATER TRANSPORT OF HYDROPHOBIC ORGANIC COMPOUNDS IN THE PRESENCE OF DISSOLVED ORGANIC MATTER  

EPA Science Inventory

The effects of dissolved organic matter (DOM) on the transport of hydrophobic organic compounds in soil columns were investigated. hree compounds (naphthalene, phenathrene, and DDT) that spanned three orders of magnitude in water solubility were used. nstead of humic matter, mole...

200

Microflow liquid chromatography coupled to mass spectrometry-an approach to significantly increase sensitivity, decrease matrix effects, and reduce organic solvent usage in pesticide residue analysis.  

PubMed

This manuscript reports a new pesticide residue analysis method employing a microflow-liquid chromatography system coupled to a triple quadrupole mass spectrometer (microflow-LC-ESI-QqQ-MS). This uses an electrospray ionization source with a narrow tip emitter to generate smaller droplets. A validation study was undertaken to establish performance characteristics for this new approach on 90 pesticide residues, including their degradation products, in three commodities (tomato, pepper, and orange). The significant benefits of the microflow-LC-MS/MS-based method were a high sensitivity gain and a notable reduction in matrix effects delivered by a dilution of the sample (up to 30-fold); this is as a result of competition reduction between the matrix compounds and analytes for charge during ionization. Overall robustness and a capability to withstand long analytical runs using the microflow-LC-MS system have been demonstrated (for 100 consecutive injections without any maintenance being required). Quality controls based on the results of internal standards added at the samples' extraction, dilution, and injection steps were also satisfactory. The LOQ values were mostly 5 ?g kg(-1) for almost all pesticide residues. Other benefits were a substantial reduction in solvent usage and waste disposal as well as a decrease in the run-time. The method was successfully applied in the routine analysis of 50 fruit and vegetable samples labeled as organically produced. PMID:25495653

Uclés Moreno, Ana; Herrera López, Sonia; Reichert, Barbara; Lozano Fernández, Ana; Hernando Guil, María Dolores; Fernández-Alba, Amadeo Rodríguez

2015-01-20

201

Predicting the environmental distribution of compounds with unknown physicochemical properties from known pesticide properties  

Microsoft Academic Search

This study examines how pesticide characteristics such as water solubility, molecular weight, bioconcentration, volatility, and soil absorption affect soil-to-water mobility, water-to-air dissipation, and water-to-biota accumulation when present in the environmental medium of preferred residence. The study concludes that chemicals that have low water solubilities tend to adsorb to soil, those that have low vapor pressures tend to dissipate slowly from

Prasad

1991-01-01

202

Pesticide Residues in Conventional, IPM-grown and Organic Foods: Insights from Three U.S. Data Sets  

NSDL National Science Digital Library

The above mentioned report by Brian P. Baker, Charles M. Benbrook, Edward Groth III, and Karen Lutz Benbrook was published in the May 2002 edition of Food Additives and Contaminants, Volume 19, No. 5. The Consumers Union (an independent nonprofit testing, educational, and information organization) has released a summary of this report for Internet viewers. According to the Consumer Union (CU), this report is the first detailed analysis of pesticide residue data in foods grown organically and conventionally. The report reveals that consumers who purchase organic fruits and vegetables are exposed to only one-third as many residues as in conventionally grown foods. The authors gathered and analyzed test data on pesticide residues in organic and non-organic foods from three independent sources: tests done on selected foods by CU in 1997; surveys of residues in foods in the US market conducted by the Pesticide Data Program of the US Department of Agriculture in 1994 through 1999; and surveys of residues in foods sold in California, tested by the California Department of Pesticide Regulation in 1989 through 1998. The combined residue data sets covered more than 94,000 food samples from more than 20 different crops of which 1,291 were organically grown. A complete copy of the paper may be purchased from the publishers of Food Additives and Contaminants.

Baker, Brian P., 1958-; Benbrook, Charles.; Benbrook, Karen L.; Groth, Edward, 1944-

2002-01-01

203

Determination of traces of several pesticides in sunflower oil using organic phase immuno electrodes (OPIEs).  

PubMed

Testing for traces of different pesticides (triazinic, organophosphates and chlorurates), present in hydrophobic matrices such as sunflower oil was checked using new immunosensors working in organic solvent mixtures (OPIEs). The competitive process took place in an n-hexane-chloroform 75% (V/V) mixture, while the subsequent final enzymatic measurement was performed in decane using tert-butylhydroperoxide as substrate of the enzymatic reaction. A Clark electrode was used as transducer and peroxidase enzyme as marker. A linear response of between about 10nM and 4?M was usually obtained in the presence of sunflower oil. Immunosensors show satisfactory selectivity and precision and recovery tests carried out on commercial sunflower oil samples gave excellent results. Lastly, theoretical confirmation of the possibility that immunosensors can act positively in organic solvent mixtures was discussed on the basis of Hill?s coefficient values. PMID:25476337

Martini, Elisabetta; Tomassetti, Mauro; Campanella, Luigi

2015-01-15

204

SDBS: Integrated Spectral Data Base System for Organic Compounds  

NSDL National Science Digital Library

Provided by Agency of Industrial Science and Technology of Japan, the Integrated Spectral Data Base System for Organic Compounds is a database of mass spectral, NMR (proton and carbon), and infrared spectra data. As of March 1999, the database contains 19,600 spectra of MS, 11,000 spectra of ^13 C NMR, 13,500 spectra of ^1 H NMR, 2,000 spectra of ESR, 47,500 spectra of IR, 3,500 spectra of Raman, and 30,000 compounds in the Compound Dictionary. A search engine (Frames) for the database allows the following fields to be specified: Compound Name, Molecular Formula, Number of Atoms (Carbon, Hydrogen, Oxygen, and Nitrogen), Molecular Weight, CAS Registry Number, and SDBS Number. Access is free; however, no more than 50 spectra and/or compound files may be downloaded in one day.

205

Sorption kinetics of hydrophobic organic compounds onto organic modified surfaces  

Microsoft Academic Search

The sorption of five chlorinated benzenes and sixteen other organic solutes was investigated by determining the extent and rate of sorption in a series of 40 batch and 139 column experiments using surface-modified silica of known chemical composition. These surfaces represented important functional groups in soil and consisted of porous silica with patchy surface coatings of aliphatic chains (Câ, Câ,

Szecsoedy

1988-01-01

206

Dosimeter for monitoring vapors and aerosols of organic compounds  

DOEpatents

A dosimeter is provided for collecting and detecting vapors and aerosols of organic compounds. The dosimeter comprises a lightweight, passive device that can be conveniently worn by a person as a badge or placed at a stationary location. The dosimeter includes a sample collector comprising a porous web treated with a chemical for inducing molecular displacement and enhancing phosphorescence. Compounds are collected onto the web by molecular diffusion. The web also serves as the sample medium for detecting the compounds by a room temperature phosphorescence technique. 7 figs.

Vo-Dinh, T.

1987-07-14

207

Dosimeter for monitoring vapors and aerosols of organic compounds  

DOEpatents

A dosimeter is provided for collecting and detecting vapors and aerosols of organic compounds. The dosimeter comprises a lightweight, passive device that can be conveniently worn by a person as a badge or placed at a stationary location. The dosimeter includes a sample collector comprising a porous web treated with a chemical for inducing molecular displacement and enhancing phosphorescence. Compounds are collected onto the web by molecular diffusion. The web also serves as the sample medium for detecting the compounds by a room temperature phosphorescence technique.

Vo-Dinh, Tuan (625 Gulfwood Rd., Knoxville, TN 37923)

1987-01-01

208

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

USGS Publications Warehouse

Concern over the presence of contaminants of emerging concern, such as pharmaceutical compounds, hormones, and organic wastewater compounds (OWCs), in waters of the United States and elsewhere is growing. Laboratory techniques developed within the last decade or new techniques currently under development within the U.S. Geological Survey now allow these compounds to be measured at concentrations in nanograms per liter. These new laboratory techniques were used in a reconnaissance study conducted by the U.S. Geological Survey, in cooperation with the Pennsylvania Department of Environmental Protection, to determine the occurrence of contaminants of emerging concern in streams, streambed sediment, and groundwater of Pennsylvania. Compounds analyzed for in the study are pharmaceuticals (human and veterinary drugs), hormones (natural and synthetic), and OWCs (detergents, fragrances, pesticides, industrial compounds, disinfectants, polycyclic aromatic hydrocarbons, fire retardants and plasticizers). Reconnaissance sampling was conducted from 2006 to 2009 to identify contaminants of emerging concern in (1) groundwater from wells used to supply livestock, (2) streamwater upstream and downstream from animal feeding operations, (3) streamwater upstream from and streamwater and streambed sediment downstream from municipal wastewater effluent discharges, (4) streamwater from sites within 5 miles of drinking-water intakes, and (5) streamwater and streambed sediment where fish health assessments were conducted. Of the 44 pharmaceutical compounds analyzed in groundwater samples collected in 2006 from six wells used to supply livestock, only cotinine (a nicotine metabolite) and the antibiotics tylosin and sulfamethoxazole were detected. The maximum concentration of any contaminant of emerging concern was 24 nanograms per liter (ng/L) for cotinine, and was detected in a groundwater sample from a Lebanon County, Pa., well. Seven pharmaceutical compounds including acetaminophen, caffeine, carbamazepine, and the four antibiotics tylosin, sulfadimethoxine, sulfamethoxazole, and oxytetracycline were detected in streamwater samples collected in 2006 from six paired stream sampling sites located upstream and downstream from animal-feeding operations. The highest reported concentration of these seven compounds was for the antibiotic sulfamethoxazole (157 ng/L), in a sample from the downstream site on Snitz Creek in Lancaster County, Pa. Twenty-one pharmaceutical compounds were detected in streamwater samples collected in 2006 from five paired stream sampling sites located upstream or downstream from a municipal wastewater-effluent-discharge site. The most commonly detected compounds and maximum concentrations were the anticonvulsant carbamazepine, 276 ng/L; the antihistamine diphenhydramine, 135 ng/L; and the antibiotics ofloxacin, 329 ng/L; sulfamethoxazole, 1,340 ng/L; and trimethoprim, 256 ng/L. A total of 51 different contaminants of emerging concern were detected in streamwater samples collected from 2007 through 2009 at 13 stream sampling sites located downstream from a wastewater-effluent-discharge site. The concentrations and numbers of compounds detected were higher in stream sites downstream from a wastewater-effluent-discharge site than in stream sites upstream from a wastewater-effluent-discharge site. This finding indicates that wastewater-effluent discharges are a source of contaminants of emerging concern; these contaminants were present more frequently in the streambed-sediment samples than in streamwater samples. Antibiotic compounds were often present in both the streamwater and streambed-sediment samples, but many OWCs were present exclusively in the streambed-sediment samples. Compounds with endocrine disrupting potential including detergent metabolites, pesticides, and flame retardants, were present in the streamwater and streambed-sediment samples. Killinger Creek, a stream where wastewater-effluent discharges contribute a large percentage of the total flow, stands out as a stream with particularly high numbers of compound

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

2012-01-01

209

Catalytic combustion of volatile organic compounds.  

PubMed

Despite the success of adsorption and thermal incineration of (C)VOC emissions, there is still a need for research on techniques which are both economically more favorable and actually destroy the pollutants rather than merely remove them for recycling elsewhere in the biosphere. The catalytic destruction of (C)VOC to CO2, H2O and HCl/Cl2 appears very promising in this context and is the subject of the present paper. The experiments mainly investigate the catalytic combustion of eight target compounds, all of which are commonly encountered in (C)VOC emissions and/or act as precursors for the formation of PCDD/F. Available literature on the different catalysts active in the oxidation of (C)VOC is reviewed and the transition metal oxide complex V2O5-WO3/TiO2 appears most suitable for the current application. Different reactor geometries (e.g. fixed pellet beds, honeycombs, etc.) are also described. In this research a novel catalyst type is introduced, consisting of a V2O5-WO3/TiO2 coated metal fiber fleece. The conversion of (C)VOC by thermo-catalytic reactions is governed by both reaction kinetics and reaction equilibrium. Full conversion of all investigated VOC to CO2, Cl2, HCl and H2O is thermodynamically feasible within the range of experimental conditions used in this work (260-340 degrees C, feed concentrations 30-60 ppm). A first-order rate equation is proposed for the (C)VOC oxidation reactions. The apparent rate constant is a combination of reaction kinetics and mass transfer effects. The oxidation efficiencies were measured with various (C)VOC in the temperature range of 260-340 degrees C. Literature data for oxidation reactions in fixed beds and honeycomb reactors are included in the assessment. Mass transfer resistances are calculated and are generally negligible for fleece reactors and fixed pellet beds, but can be of importance for honeycomb monoliths. The experimental investigations demonstrate: (i) that the conversion of the hydrocarbons is independent of the oxygen concentration, corresponding to a zero-order dependency of the reaction rate; (ii) that the conversion of the hydrocarbons is a first-order reaction in the (C)VOC; (iii) that the oxidation of the (C)VOC proceeds to a higher extent with increasing temperature, with multiple chlorine substitution enhancing the reactivity; (iv) that the reaction rate constant follows an Arrhenius dependency. The reaction rate constant kr (s(-1)) and the activation energy E (kJ/mol) are determined from the experimental results. The activation energy is related to the characteristics of the (C)VOC under scrutiny and correlated in terms of the molecular weight. The kr-values are system-dependent and hence limited in design application to the specific VOC-catalyst combination being studied. To achieve system-independency, kr-values are transformed into an alternative kinetic constant K (m3/(m2u)) expressed per unit of catalyst surface and thus independent of the amount of catalyst present in the reactor. Largely different experimental data can be fitted in terms of this approach. Results are thereafter used to define the Arrhenius pre-exponential factor A*, itself expressed in terms of the activation entropy. Destruction efficiencies for any given reactor set-up can be predicted from E- and A*-correlations. The excellent comparison of predicted and measured destruction efficiencies for a group of chlorinated aromatics stresses the validity of the design approach. Since laboratory-scale experiments using PCDD/F are impossible, pilot and full-scale tests of PCDD/F oxidation undertaken in Flemish MSWIs and obtained from literature are reported. From the data it is clear that: (i) destruction efficiencies are normally excellent; (ii) the efficiencies increase with increasing operating temperature; (iii) the higher degree of chlorination does not markedly affect the destruction efficiency. Finally, all experimental findings are used in design recommendations for the catalytic oxidation of (C)VOC and PCDD/F. Predicted values of the a)VOC and PCDD/F. Predicted values of the a

Everaert, K; Baeyens, J

2004-06-18

210

Efficiency dependence on alkali metal compound/Al bilayer cathode in organic light-emitting diodes  

NASA Astrophysics Data System (ADS)

The use of alkali metal compound/Al bilayer cathodes of LiF/Al and Liq/Al caused a dramatic luminous efficiency change of one order of magnitude in organic light-emitting diodes (OLEDs) comprising 2-methyl-9,10-bis(naphthalene-2-yl)anthracene (MADN) as an electron-transporting layer (ETL). In contrast, the use of the same two electrodes yielded similar efficiency in OLEDs comprising of tris(8-hydroxyquinoline) aluminum(III) (Alq3) as an ETL. The dramatic change is attributed to different behaviors of LiF/Al and Liq/Al cathodes toward the ETL. It is revealed that organic alkali metal complex/Al, such as Liq/Al, is superior to inorganic alkali metal compound/Al, such as LiF/Al, as a standard bilayer cathode to investigate the effectiveness of electron-transporting materials for high-efficiency OLEDs.

Zhou, D. Y.; Cai, S. D.; Gu, W.; Liao, L. S.; Lee, S. T.

2010-11-01

211

Influence of alternating soil drying and wetting on the desorption and distribution of aged 14C-labeled pesticide residues in soil organic fractions  

NASA Astrophysics Data System (ADS)

A laboratory experiment was conducted to evaluate the effect of alternating soil drying and wetting on the release of aged 14C-labeled pesticide residues and their distribution in soil organic fractions (humic acids, fulvic acids, and humin substances). The used soils (gleyic cambisol; Corg 1.2%, pH 7.2) were obtained from the upper soil layer of two individual outdoor lysimeter studies containing either environmentally long-term aged 14C residues of the herbicide ethidimuron (ETD; 0-10 cm depth; time of aging: 9 years) or methabenzthiazuron (MBT; 0-30 cm depth; time of aging: 17 years). Triplicate soil samples (10 g dry soil equivalents) were (A=dry/wet) previously dried (45° C) or (B=wet/wet) directly mixed with pure water (1+2, w:w), shaken (150 rpm, 1 h), and centrifuged (~2000 g). The resulting supernatant was removed, filtered (0.45 ?m) and subjected to 14C activity analysis via liquid scintillation counter (LSC), dissolved organic carbon (DOC) analysis, and LC-MS-MS analysis. This extraction procedure was repeated 15 individual times, for both setups (A) and (B). To determine the distribution of the aged 14C labelled pesticide residues in the soil organic matter fractions, the soil samples were subject to humic and fulvic acids fractionations at cycles 0, 4, 10, and 15. The residual pesticide 14C activity associated with the humic, fulvic, and humin substances (organic fraction remaining in the soil) fractions was determined via LSC. The water-extracted residual 14C activity was significantly higher in the extracts of the dry/wet, compared to the wet/wet soil samples for both pesticides. The total extracted 14C activity in the dry/wet soil extracts accounted for 51.0% (ETD) and 15.4% (MBT) in contrast to 19.0% (ETD) and 4.7% (MBT) in the wet/wet extracts after 15 water extractions. LC-MS-MS analysis revealed the parent compound ETD 27.9 ?g kg-1 soil (dry/wet) and 10.7 ?g kg-1 soil (wet/wet), accounting for 3.45 and 1.35% of total parent compound initially applied after a total of 10 water extractions, respectively. MBT was detected but not quantified, whereas its metabolite MABT (2-methylamino-benzothiazole) was detected (0.8 vs 0.3 ?g kg-1, in dry/wet vs wet/wet soil water extracts, respectively) after 10 water extractions. These results demonstrate the long-term persistence of ETD and MBT and metabolites and their remobilization potential facilitated by soil drying and rewetting. For all samples, the DOC content was significantly higher for the water extracts obtained after dry/wet cycles compared to values obtained from the constantly moistened soil samples. The DOC and water extracted residual 14C activity correlated positively. This result indicates that pesticide residues are associated with DOC which might function as a shuttle for the distribution of pesticide residues. This molecular association can be released into solution where it might be degraded co-metabolically. Overall, the results suggest that intermittent soil drying and rewetting alters the disaggregation of soil aggregates, resulting in a release of entrapped organic carbon and pesticide molecules. Furthermore, analysis of the organic fractions obtained from the 14C pesticide residues containing soil revealed that 14C residues were mainly associated with the humin fraction. The analysis of the organic fractions revealed that extractable residual 14C activity of ETD was more associated with the fulvic acid fraction compared to the residual pesticide 14C activity of MBT, being more associated with the humic acid fraction. For 14C MBT residues, the distribution of the 14C residues in the organic fractions remained rather equal throughout the water extraction cycles. This observation can be supported by the non-mobile character of MBT in soil and its higher KOC value of 247-587 compared to the rather mobile pesticide ETD with a KOC value of 37.1-149. However, for both pesticides a decrease of residual 14C activity in the humic and fulvic acid fractions throughout the water extractions cycles was observed. This observation was more pronounced

Jablonowski, N. D.; Mucha, M.; Thiele, B.; Hofmann, D.; Burauel, P.

2012-04-01

212

Acute toxicity assessment of Osthol content in bio-pesticides using two aquatic organisms  

PubMed Central

Objectives This study focused on the assessment of acute toxicity caused by Osthol, a major component of environment-friendly biological pesticides, by using two aquatic organisms. Methods The assessment of acute toxicity caused by Osthol was conducted in Daphnia magna and by examining the morphological abnormalities in Danio rerio embryos. Results The median effective concentration value of Osthol in D. magna 48 hours after inoculation was 19.3 ?M. The median lethal concentration of D. rerio embryo at 96 hours was 30.6 ?M. No observed effect concentration and predicted no effect concentration values of Osthol in D. magna and D. rerio were calculated as 5.4 and 0.19 ?M, respectively. There was an increase in the morphological abnormalities in D. rerio embryo due to Osthol over time. Coagulation, delayed hatching, yolk sac edema, pericardial edema, and pigmentation were observed in embryos at 24–48 hours. Symptoms of scoliosis and head edema occurred after 72 hours. In addition, bent tails, ocular defects, and symptoms of collapse were observed in fertilized embryo tissue within 96 hours. Ocular defects and pigmentation were the additional symptoms observed in this study. Conclusions Because Osthol showed considerable toxicity levels continuous toxicity evaluation in agro-ecosystems is necessary when bio-pesticides containing Osthol are used. PMID:25518842

Yim, Eun-Chae; Kim, Hyeon Joe; Kim, Seong-Jun

2014-01-01

213

Calibration and field application of passive sampling for episodic exposure to polar organic pesticides in streams.  

PubMed

Rainfall-triggered runoff is a major driver of pesticide input in streams. Only few studies have examined the suitability of passive sampling to quantify such episodic exposures. In this study, we used Empore™ styrene-divinylbenzene reverse phase sulfonated disks (SDB disks) and event-driven water samples (EDS) to assess exposure to 15 fungicides and 4 insecticides in 17 streams in a German vineyard area during 4 rainfall events. We also conducted a microcosm experiment to determine the SDB-disk sampling rates and provide a free-software solution to derive sampling rates under time-variable exposure. Sampling rates ranged from 0.26 to 0.77 L d(-1) and time-weighted average (TWA) concentrations from 0.05 to 2.11 ?g/L. The 2 sampling systems were in good agreement and EDS exceeded TWA concentrations on average by a factor of 3. Our study demonstrates that passive sampling is suitable to quantify episodic exposures from polar organic pesticides. PMID:25150453

Fernández, Diego; Vermeirssen, Etiënne L M; Bandow, Nicole; Muñoz, Katherine; Schäfer, Ralf B

2014-11-01

214

EVALUATION OF FARMERS APPRECIATION IN REDUCING PESTICIDE BY ORGANIC FARMING PRACTICE  

Microsoft Academic Search

Vegetables and dairy milk are important commodities in Panga- lengan and Lembang, West Java. However, agrochemicals are used intensively and excessively in production system. There- fore, pesticide residues and contamination commonly occurred in agricultural products and environments. The study aimed to assess farmers' attitudes on pesticide toxicity and reducing pesticide residues in animal and food crops products, and investigate the

Raphaella Widiastuti; Jalan R. E. Martadinata

215

Monitoring of some pesticides residues in different samples of meat and some organs of cattle.  

PubMed

Intensive use of pesticides for controlling pests in Egypt resulted in presence of minute amount of their residue in animal feeds and consequently in animal tissues. The present study aimed to monitor the residue of some commonly used pesticides in different samples of animal tissues obtained from rural areas. The results revealed high concentration of pesticides residue in liver and kidney. PMID:17217017

el-Aziz, T A

1996-01-01

216

Sensing based on Mach-Zehnder interferometer and hydrophobic thin films used on volatile organic compounds detection  

NASA Astrophysics Data System (ADS)

This paper presents the project, optimization, design details, and fabrication of an optical chemical sensor based on a Mach-Zehnder interferometer (MZI), fabricated with metal-oxide semiconductor compatible processes and materials. The sensing material is hexamethyldissilazane (HMDS) plasma polymerized thin film, which exhibits hydrophobic characteristics, high resistance to acid or basic solution, and adsorption of polar and nonpolar organic compounds. Both reference and sensor arms of the fabricated MZIs are covered with HMDS thin film in order to keep the device balanced. Different substances, such as water, 2-propanol, and hexane vapors are investigated. The high sensitivity of the MZI structure, associated with refractive index variations of about 10-4, paves the way for a myriad of sensor applications, such as humidity, organic compounds, proteins, antibodies (antigens), enzymes, pesticides, and others. The minimum detectable measurements were 4.6 mg/min for n-hexane and 0.2 mg/min for 2-propanol.

Siarkowski, Acácio Luiz; Hernandez, Leonardo Frois; Borges, Ben-Hur Viana; Morimoto, Nilton Itiro

2012-05-01

217

ABSTRACT: Organophosphate (OP) compounds are present in house-hold and agricultural pesticides as well as in nerve agents. The toxic effects  

E-print Network

ABSTRACT: Organophosphate (OP) compounds are present in house- hold and agricultural pesticides INDICATOR OF ORGANOPHOSPHATES IN THE BODY CARLO J. DE LUCA, PhD,1 JERRY J. BUCCAFUSCO, PhD,2 SERGE H. ROY Accepted 22 September 2005 Organophosphate (OP) cholinesterase inhibitors form the active ingredient

De Luca, Carlo J.

218

Trace element, semivolatile organic, and chlorinated organic compound concentrations in bed sediments of selected streams at Fort Gordon, Georgia, February-April 2010  

USGS Publications Warehouse

A spatial survey of streams was conducted from February to April 2010 to assess the concentrations of major ions, selected trace elements, semivolatile organic compounds, organochlorine pesticides, and polychlorinated biphenyls associated with the bed sediments of surface waters at Fort Gordon military installation near Augusta, Georgia. This investigation expanded a previous study conducted in May 1998 by the U.S. Geological Survey, in cooperation with the U.S. Department of the Army Environmental and Natural Resources Management Office of the U.S. Army Signal Center and Fort Gordon, that evaluated the streambed sediment quality of selected surface waters at Fort Gordon. The data presented in this report are intended to help evaluate bed sediment quality in relation to guidelines for the protection of aquatic life, and identify temporal trends in trace elements and semivolatile organic compound concentrations at streambed sites previously sampled. Concentrations of 34 major ions and trace elements and 102 semivolatile organic, organochlorine pesticide, and polychlorinated biphenyl compounds were determined in the fine-grained fraction of bed sediment samples collected from 13 of the original 29 sites in the previous study, and 22 additional sites at Fort Gordon. Three of the sites were considered reference sites as they were presumed to be located away from potential sources of contaminants and were selected to represent surface waters flowing onto the fort, and the remaining 32 nonreference sites were presumed to be located within the contamination area at the fort. Temporal trends in trace elements and semivolatile organic compound concentrations also were evaluated at 13 of the 32 nonreference sites to provide an assessment of the variability in the number of detections and concentrations of constituents in bed sediment associated with potential sources, accumulation, and attenuation processes. Major ion and trace element concentrations in fine-grained bed sediment samples from most nonreference sites exceeded concentrations in samples from reference sites at Fort Gordon. Bed sediments from one of the nonreference sites sampled contained the highest concentrations of copper and lead with elevated levels of zinc and chromium relative to reference sites. The percentage change of major ions, trace elements, and total organic carbon that had been detected at sites previously sampled in May 1998 and current bed sediment sites ranged from -4 to 8 percent with an average percentage change of less than 1 percent. Concentrations of major ions and trace elements in bed sediments exceeded probable effect levels for aquatic life (based on the amphipod Hyalella azteca) established by the U.S. Environmental Protection Agency at 46 and 69 percent of the current and previously sampled locations, respectively. The greatest frequency of exceedances for major ions and trace elements in bed sediments was observed for lead. Concentrations of semivolatile organic compounds, organochlorine pesticides, and polychlorinated biphenyls were detected in bed sediment samples at 94 percent of the sites currently sampled. Detections of these organic compounds were reported with greater frequency in bed sediments at upstream sampling locations, when compared to downstream locations. The greatest number of detections of these compounds was reported for bed sediment samples collected from two creeks above a lake. The percentage change of semivolatile organic compounds detected at previously sampled and current bed sediment sites ranged from -68 to 100 percent with the greatest percentage increase reported for one of the creeks above the lake. Concentrations of semivolatile organic compounds and polychlorinated biphenyls in bed sediments exceeded aquatic life criteria established by the U.S. Environmental Protection Agency at three sites. Contaminant compounds exceeding aquatic life criteria included fluoranthene, phenanthrene, anthracene, benzo(a)anthracene

Thomas, Lashun K.; Journey, Celeste A.; Stringfield, Whitney J.; Clark, Jimmy M.; Bradley, Paul M.; Wellborn, John B.; Ratliff, Hagan; Abrahamsen, Thomas A.

2011-01-01

219

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

USGS Publications Warehouse

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

Banks, William S.L.; Reyes, Betzaida

2009-01-01

220

Organic Compounds in Elm Fork Trinity River Water Used for Public Supply near Carrollton, Texas, 2002-05  

USGS Publications Warehouse

Organic compounds studied in this U.S. Geological Survey (USGS) assessment generally are man-made, including pesticides, solvents, gasoline hydrocarbons, personal-care and domestic-use products, refrigerants, and propellants. A total of 103 of 277 compounds were detected at least once among the 30 samples of source water for a community water system on the Elm Fork Trinity River near Carrollton, Texas, collected approximately monthly during 2002-05. The diversity of compounds detected indicates a variety of different sources and uses (including wastewater discharge, industrial, agricultural, domestic, and others) and different pathways (including overland runoff and groundwater discharge) to drinking-water supplies. Nine compounds were detected year-round in source-water samples, including chloroform, methyl tert-butyl ether (MTBE), and selected herbicide compounds commonly used in the Trinity River Basin and in other urban areas across the United States. About 90 percent of the 42 compounds detected most frequently in source water (in at least 20 percent of the samples) also were detected most frequently in finished water (after treatment but before distribution). Concentrations for all detected compounds in source and finished water generally were less than 0.1 microgram per liter and always less than human-health benchmarks, which are available for about one-half of the detected compounds.

Ging, Patricia B.; Delzer, Gregory C.; Hamilton, Pixie A.

2009-01-01

221

Analysis of Organic Compounds in Mars Analog Samples  

NASA Technical Reports Server (NTRS)

The detailed characterization of organic compounds that might be preserved in rocks, ices, or sedimentary layers on Mars would be a significant step toward resolving the question of the habitability and potential for life on that planet. The fact that the Viking gas chromatograph mass spectrometer (GCMS) did not detect organic compounds should not discourage further investigations since (a) an oxidizing environment in the near surface fines analyzed by Viking is likely to have destroyed many reduced carbon species; (b) there are classes of refractory or partially oxidized species such as carboxylic acids that would not have been detected by the Viking GCMS; and (c) the Viking landing sites are not representative of Mars overall. These factors motivate the development of advanced in situ analytical protocols to carry out a comprehensive survey of organic compounds in martian regolith, ices, and rocks. We combine pyrolysis GCMS for analysis of volatile species, chemical derivatization for transformation of less volatile organics, and laser desorption mass spectrometry (LDMS) for analysis of elements and more refractory, higher-mass organics. To evaluate this approach and enable a comparison with other measurement techniques we analyze organics in Mars simulant samples.

Mahaffy, P. R.; Brinckerhoff, W. B.; Buch, A.; Cabane, M.; Coll, P.; Demick, J.; Glavin, D. P.

2004-01-01

222

Key volatile organic compounds emitted from swine nursery house  

NASA Astrophysics Data System (ADS)

This study was carried out to quantify the concentration and emission levels of key volatile organic compounds (VOCs) - sulfides, indolics, phenolics and volatile fatty acids (VFA) - emitted from swine nursery house, and assess the effect of microclimate (including temperature, relative humidity and air speed) on the key odorous compounds. Samples were collected from the Experimental Farm of Seoul National University in Suwon, South Korea. And the collection took place for four seasons and the sampling time was fixed at 10:30 in the morning. The application of one-way ANOVA and Bonferroni t analyses revealed that, most of the odorous compound concentrations, such as dimethyl sulfide (DMS), dimethyl disulfide (DMDS), indole, p-cresol and all the volatile fatty acids were lowest during the summer ( P < 0.01). Meanwhile, negative correlations were observed between temperature and odorants, as well as air speed and odorants. A possible reason was that high ventilation transferred most of the odors out of the house during the summer. From the whole year data, non-linear multiple regressions were conducted and the equations were proposed depending upon the relationships between microclimate parameters and odorous compounds. The equations were applied in hope of easily calculating the concentrations of the odorous compounds in the commercial farms. The results obtained in this study should be used for reducing the volatile organic compounds by controlling microclimate parameters and also could be helpful in setting a guideline for good management practices in nursery house.

Yao, H. Q.; Choi, H. L.; Zhu, K.; Lee, J. H.

2011-05-01

223

Detection limits of organochlorine pesticides and related compounds in blood serum  

SciTech Connect

Determinations of organochlorine pesticides and similar chemical residues in blood serum have often reported detection limits of 1 ng/mL. When a study group has incurred body burdens lower than this, underestimates and misclassifications of exposure may occur because persons with pesticide residue concentration below the limit of detection are usually treated as zeros.' Thus in order to more accurately assess exposures in such populations, analysis of adipose tissue has been done. Recently, with TCDD, use of a sufficient volume of serum, as much as 0.5 L, in conjunction with appropriate analytical techniques has been shown to achieve detection limits necessary for epidemiological assessments, i.e., comparable to analysis of adipose tissue. In a population-based study involving children in which the authors were involved, it was not feasible to obtain specimens of either adipose or a large volume of serum. There was no compelling health motivation for such measures, nor did they wish to impair participation rates. Therefore, they chose to optimize the existing serum analysis, in order to achieve a detection limit low enough to assess reasonably the anticipated exposures.

Wolff, M.S.; Rivera, M.; Baker, D.B. (Mount Sinai School of Medicine, New York, NY (United States))

1991-10-01

224

VOLATILE ORGANIC COMPOUND MODEL (VERSION 1.8) (FOR MICROCOMPUTERS)  

EPA Science Inventory

Future emissions of volatile organic compounds (VOCs) and costs of their control can be estimated by applying growth factors, emission constraints, control cost functions, and capacity retirement rates to the base line estimates of VOC emissions and industrial VOC source capacity...

225

The Survival of Meteorite Organic Compounds with Increasing Impact Pressure  

NASA Technical Reports Server (NTRS)

The majority of carbonaceous meteorites studied today are thought to originate in the asteroid belt. Impacts among asteroidal objects generate heat and pressure that may have altered or destroyed pre-existing organic matter in both targets and projectiles to a greater or lesser degree depending upon impact velocities. Very little is known about the shock related chemical evolution of organic matter relevant to this stage of the cosmic history of biogenic elements and compounds. The present work continues our study of the effects of shock impacts on selected classes of organic compounds utilizing laboratory shock facilities. Our approach was to subject mixtures of organic compounds, embedded in a matrix of the Murchison meteorite, to a simulated hypervelocity impact. The molecular compositions of products were then analyzed to determine the degree of survival of the original compounds. Insofar as results associated with velocities < 8 km/sec may be relevant to impacts on planetary surfaces (e.g., oblique impacts, impacts on small outer planet satellites) or grain-grain collisions in the interstellar medium, then our experiments will be applicable to these environments as well.

Cooper, George; Horz, Friedrich; Oleary, Alanna; Chang, Sherwood; DeVincenzi, Donald L. (Technical Monitor)

2000-01-01

226

NATIONAL AMBIENT VOLATILE ORGANIC COMPOUNDS (VOCS) DATA BASE UPDATE, DOCUMENTATION  

EPA Science Inventory

Data on the observed concentrations of three hundred twenty (320) volatile organic compounds (VOCs) were compiled, critically evaluated, and assembled into a relational data base. Ambient (i.e., outdoor) measurements, indoor data, and data collected with personal monitors are inc...

227

Volatile Organic Compounds in Untreated Ambient Groundwater of  

E-print Network

Volatile Organic Compounds in Untreated Ambient Groundwater of the United States, 1985-1995 P A U L, ambient groundwater of the conterminous United States was conducted based on samples collected from 2948-chloropropane, which had a reporting level of 1.0 µg/L. Because ambient groundwater was targeted, areas of known

228

Modeling emissions of volatile organic compounds from silage  

Technology Transfer Automated Retrieval System (TEKTRAN)

Photochemical smog is a major air pollution problem and a significant cause of premature death in the U.S. Smog forms in the presence of volatile organic compounds (VOCs), which are emitted primarily from industry and motor vehicles in the U.S. However, dairy farms may be an important source in so...

229

A global model of natural volatile organic compound emissions  

Microsoft Academic Search

Numerical assessments of global air quality and potential changes in atmospheric chemical constituents require estimates of the surface fluxes of a variety of trace gas species. We have developed a global model to estimate emissions of volatile organic compounds from natural sources (NVOC). Methane is not considered here and has been reviewed in detail elsewhere. The model has a highly

Alex Guenther; C. Nicholas Hewitt; David Erickson; Ray Fall; Chris Geron; Tom Graedel; Peter Harley; Lee Klinger; Manuel Lerdau; W. A. McKay; Tom Pierce; Bob Scholes; Rainer Steinbrecher; Raja Tallamraju; John Taylor; Pat Zimmerman

1995-01-01

230

Who Took Jerell's iPod? -- An Organic Compound Mystery  

NSDL National Science Digital Library

In this activity, students learn how to test for triglycerides, glucose, starch, and protein and then use these tests to solve a mystery. The activity reinforces students understanding of the biological functions and food sources of these different types of organic compounds.

Doherty, Jennifer; Waldron, Ingrid

231

MICROBIAL VOLATILE ORGANIC COMPOUND EMISSION RATES AND EXPOSURE MODEL  

EPA Science Inventory

This paper presents the results from a study that examined microbial volatile organic compound (MVOC) emissions from six fungi and one bacterial species (Streptomyces spp.) commonly found in indoor environments. Data are presented on peak emission rates from inoculated agar plate...

232

ABSORPTION OF SOME ORGANIC COMPOUNDS THROUGH THE SKIN IN MAN  

Microsoft Academic Search

We studied the percutaneous penetration of 21 organic chemicals. The experimental method consisted of the application of the chemical to the human forearm and quantitating its penetration through the skin by its appearance in urine.There was a great diversity in the ability of the chemicals to penetrate human skin. Compounds such as hippuric acid, nicotinic acid, and nitrobenzene support the

Robert J. Feldmann; Howard I. Maibach

1970-01-01

233

Volatile Organic Compound Emissions from Dairy Cows and  

E-print Network

Volatile Organic Compound Emissions from Dairy Cows and Their Waste as Measured by Proton California dairies house approximately 1.8 million lactating and 1.5 million dry cows and heifers. State air from lactating and dry dairy cowsandtheirwasteusinganenvironmentalchamber.Carbon dioxide and methane

Goldstein, Allen

234

PHOTOTHERMAL DESTRUCTION OF THE VAPOR OF ORGANIC COMPOUNDS  

EPA Science Inventory

The results of thermal and photothermal destruction of the vapors of organic compounds were compared by conducting tests in a photothermal detoxification unit. enon are lamp was used as the irradiation source. he tests were conducted on trichlorethylene (TCE), 1,2-dichlorobenzene...

235

FIELD-DEPLOYABLE MONITORS FOR VOLATILE ORGANIC COMPOUNDS IN AIR  

EPA Science Inventory

Volatile organic compounds in ambient air are usually estimated by trapping them from air or collecting whole air samples and returning them to a laboratory for analysis by gas chromatography using selective detection. ata do not appear for several days, during which sample integ...

236

AERATION TO REMOVE VOLATILE ORGANIC COMPOUNDS FROM GROUND WATER  

EPA Science Inventory

The interim report presents general information on the use of aeration to remove volatile organic compounds from drinking water for public health reasons. The report illustrates the types of aerators, shows where they are being used, presents a means of estimating aeration perfor...

237

Concentrations of volatile organic compounds (VOCs) at an oil refinery  

Microsoft Academic Search

This study measured and analysed individual volatile organic compounds (VOCs), total hydrocarbon and total VOCs at an oil refinery. Measurements were taken at various workplace locations, of the ambient air and at some off?site facilities such as its gantry terminals, ETP and tank farms. The study also identified certain pollutants that are difficult to measure routinely but could give an

G. H. Pandya; A. G. Gavane; A. D. Bhanarkar; V. K. Kondawar

2006-01-01

238

MEASUREMENT OF ORGANIC COMPOUND EMISSIONS USING SMALL TEST CHAMBERS  

EPA Science Inventory

Organic compounds emitted from a variety of indoor materials have been measured using small (166 L) environmental test chambers. The paper discusses: a) factors to be considered in small chamber testing; b) parameters to be controlled; c) the types of results obtained. The follow...

239

Problems in determining the water solubility of organic compounds  

Microsoft Academic Search

We have been concerned for some time about the reliability of published water solubility data for organic compounds with low solubility. The problem was illustrated by the results of our studies on the solubility of the liquid trichlorobenzene (TCB). We found that the apparent solubility is strongly dependent on the method of introducing the solute into the water (Orr 1980).

A. Bharath; C. Mallard; D. Orr; G. Ozburn; A. Smith

1984-01-01

240

Volatile organic compounds in indoor air: Types, sources, and characteristics  

Microsoft Academic Search

Examples are given of occupant activities and consumer and construction products inside residences that cause transient and persistent emissions of volatile organic compounds (VOC). Transient emissions arise from window cleaning, carpet laying, smoking, and automobile operations. Persistent VOC emitters include gasoline, mothballs and pressed-wood products containing urea-formaldehyde resins. Simple screening methods are given for making indoor measurements of VOC. Detailed

R. B. Gammage; T. G. Matthews

1987-01-01

241

Biogenic volatile organic compounds in the Earth system.  

PubMed

Biogenic volatile organic compounds produced by plants are involved in plant growth, development, reproduction and defence. They also function as communication media within plant communities, between plants and between plants and insects. Because of the high chemical reactivity of many of these compounds, coupled with their large mass emission rates from vegetation into the atmosphere, they have significant effects on the chemical composition and physical characteristics of the atmosphere. Hence, biogenic volatile organic compounds mediate the relationship between the biosphere and the atmosphere. Alteration of this relationship by anthropogenically driven changes to the environment, including global climate change, may perturb these interactions and may lead to adverse and hard-to-predict consequences for the Earth system. PMID:19422541

Laothawornkitkul, Jullada; Taylor, Jane E; Paul, Nigel D; Hewitt, C Nicholas

2009-01-01

242

Thermodynamic equilibrium and the inorganic origin of organic compounds.  

PubMed

Theoretical and experimental support is presented for the hypothesis that many organic compounds may form under conditions of thermodynamic equilibrium. This possibility must be considered along with special effects of selective catalysts, radiation, and degradation from biological matter, in explaining the origin of organic compounds in carbonaceous chondrites. Similar considerations may apply to solar nebulas and planetary atmospheres. The equilibrium distribution of organic compounds at temperatures between 300 degrees K and 1000 degrees K and pressures of 10-(6) to 50 atm for the C-H-O system have been computed. At moderate temperatures and low pressures, conditions where graphite production is inhibited, aromatic compounds may form even in the presence of large excesses of hydrogen. Such conditions exist in the solar nebula and in the atmospheres of some of the major planets. Equilibrium concentrations of a large number of compounds at 1000 degrees K with nitrogen, sulfur, and chlorine added to the system have also been determined. In some cases, a limited equilibrium method is employed in which those few compounds which form with the most difficulty are excluded from the computations, while representatives of all other families of compounds are included. This approach is shown to be useful in the interpretation of certain experimental data in which complete equilibrium has not been attained. We have also found that gases, activated to the plasma state by a high-energy radio frequency field, recombine on cooling to yield product mixtures which are in qualitative agreement with those predicted by the equilibrium computations. We believe that such products can be profitably studied as if at a metastable limited equilibrium. PMID:17757236

Eck, R V; Lippincott, E R; Dayhoff, M O; Pratt, Y T

1966-08-01

243

Composition of volatile organic compounds in flowers of Astragalus sahendi.  

PubMed

A hydrodistillation sampling method, coupled to gas chromatography-mass spectrometry, was used in monitoring the volatile organic compounds in flowers of Astragalus sahendi. Accordingly, a total of 48 compounds were recognised, which were united by their terpenoid or aliphatic skeletons and low molecular weight. Above all, the significant presence of some insect-favoured terpenoid compounds, such as farnesol, cis- and trans-geraniol, alpha-bisabolol, nerolidol isomer, alpha-terpineol, alpha-terpinolene and thymol was significant. These findings confer a better understanding of pollination processes in the giant genus Astragalus. Furthermore, the results add to an increasing quantity of data corroborating the ecologic and evolutionary correlation between the floral bioactive compounds of plant species and their special types of pollinators. PMID:20803377

Movafeghi, A; Delazar, A; Amini, M; Asnaashari, S; Nazifi, E

2010-09-01

244

Water solubility enhancement of some organic pollutants and pesticides by dissolved humic and fulvic acids  

USGS Publications Warehouse

Water solubility enhancements by dissolved humic and fulvic acids from soil and aquatic origins and by synthetic organic polymers have been determined for selected organic pollutants and pesticides (p,p???-DDT, 2,4,5,2???,5???-PCB, 2,4,4???-PCB, 1,2,3-trichlorobenzene, and lindane). Significant solubility enhancements of relatively water-insoluble solutes by dissolved organic matter (DOM) of soil and aquatic origins may be described in terms of a partition-like interaction of the the solutes with the microscopic organic environment of the high-molecular-weight DOM species; the apparent solute solubilities increase linearly with DOM concentration and show no competitive effect between solutes. With a given DOM sample, the solute partition coefficient (Kdom) increases with a decrease of solute solubility (Sw) or with an increase of the solute's octanol-water partition coefficient (Kow). The Kdom values of solutes with soil-derived humic acid are approximately 4 times greater than with soil fulvic acid and 5-7 times greater than with aquatic humic and fulvic acids. The effectiveness of DOM in enhancing solute solubility appears to be largely controlled by the DOM molecular size and polarity. The relative inability of high-molecular-weight poly(acrylic acids) to enhance solute solubility is attributed to their high polarities and extended chain structures that do not permit the formation of a sizable intramolecular nonpolar environment.

Chiou, C.T.; Malcolm, R.L.; Brinton, T.I.; Kile, D.E.

1986-01-01

245

Water solubility enhancement of some organic pollutants and pesticides by dissolved humic and fulvic acids  

SciTech Connect

Water solubility enhancements by dissolved humic and fulvic acids from soil and aquatic origins and by synthetic organic polymers have been determined for selected organic pollutants and pesticides (p,p'-DDT,2,4,5,2',5'-PCB, 2,4,4'-PCB, 1,2,3,-trichlorobenzene, and lindane). Significant solubility enhancements of relatively water-insoluble solutes by dissolved organic matter (DOM) of soil and aquatic origins may be described in terms of a partition-like interaction of the solutes with the microscopic organic environment of the high-molecular-weight DOM species; the apparent solute solubilities increase linearly with DOM concentration and show no competitive effect between solutes. The K/sub dom/ values of solutes with soil-derived humic acid are approximately 4 times greater than with soil fulvic acid and 5-7 times greater than with aquatic humic and fulvic acids. The effectiveness of DOM in enhancing solute solubility appears to be largely controlled by the DOM molecular size and polarity. The relative inability of high-molecular-weight poly(acrylic acids) to enhance solute solubility is attributed to their high polarities and extended chain structures that do not permit the formation of a sizable intramolecular nonpolar environment. 41 references, 6 figures, 3 tables.

Chiou, C.T.; Malcolm, R.L.; Brinton, T.I.; Kile, D.E.

1986-05-01

246

Organic compounds as indicators for transport in an urban characterized complex karst system  

NASA Astrophysics Data System (ADS)

In northern Hesse (Germany), sediments of the Upper Permian (Zechstein-Formations) are outcropping in a coastal facies along the western rim of the Rhenish Massif. The geologic section is characterized by a sequence of carbonate rocks (carbonates of the Werra-, Staßfurt- and Leine-Formations) and predominantly fine clastic sediments. The carbonate aquifers of the Werra-Formation and the Leine-Formation are used for drinking water abstraction of a provincial town and surrounding communities. Concurrently, the urban area is characterized by industrial and commercial uses. The groundwater flow system is composed of three potential karst aquifers, aquitards and aquicludes within a complex tectonically faulted area. The study area is divided into three spring catchment areas. However, the locations of the subsurface water divides are unknown. Traditional methods to determine the catchment areas (e.g. artificial tracer tests) are difficult to apply, due to a lack of adequate injection points. The presented work deals with the use of organic compounds as indicators for subsurface flow paths. Medical drugs, pesticides, corrosion inhibitors and such typical waste water compounds as caffeine (NÖDLER ET AL. 2010) are observed in approximately fifty groundwater observation points by regular sampling. The seasonal variability of the distribution pattern of organic compounds is low. The most common compounds are atrazine and its metabolites desethylatrazine and desisopropylatrazine, as well as the corrosion inhibitor 1H-benzotriazole. Since these substances are applied in different regions different input functions can be assumed. However, the highest concentrations are detected along a North-orientated axis, which also exhibits the greatest compound variety. This distribution pattern indicates preferential flow and transport pathways in the subsurface. The absence of organic compounds in other parts of the investigation area implies the existence of a water divide between these areas. The occurence of atrazine in groundwater samples denotes the existence of a water component with a transit time of more than 20 years because the use of atrazine as a pesticide has been banned in Germany since 1991. Furthermore, since atrazine and 1H-benzotriazole are found in all investigated aquifers, the presence of hydraulic connections between the aquifers (e.g. associated to faults) is likely. In addition to the long-term flow component, the periodic detection of such antibiotics as erythromycine, after strong recharge events (for example snow-melt events), suggests also the presence of a short-term flow component in the aquifer system. Consequently, the observation of organic compounds is an appropriate method to determine subsurface flow paths within complex aquifer systems. Furthermore, such a method can also be employed in the subsurface to approximate transit times and to identify mixing zones. Lecture NÖDLER, K., LICHA, T., BESTER, B., K. SAUTER, M. (2010): Development of a multi-residue analytical method, based on liquid chromatography-tandem mass spectrometry, for the simultaneous determination of 46 micro-contaminants in aqueous samples.- Journal of Chromatography A, 1217 (2010) 6511-6521.

Reh, R.; Licha, T.; Nödler, K.; Geyer, T.; Sauter, M.

2012-04-01

247

Measurements of halogenated organic compounds near the tropical tropopause  

NASA Technical Reports Server (NTRS)

The amount of organic chlorine and bromine entering the stratosphere have a direct influence on the magnitude of chlorine and bromine catalyzed ozone losses. Twelve organic chlorine species and five organic bromine species were measured from 12 samples collected near the tropopause between 23.8 deg N and 25.3 deg N during AASE 2. The average mixing ratios of total organic chlorine and total organic bromine were 3.50 +/- 0.06 ppbv and 21.1 +/- 0.8 pptv, respectively. CH3Cl represented 15.1% of the total organic chlorine, with CFC 11 (CCl3F) and CFC 12 (CCl2F2) accounting for 22.6% and 28.2%, respectively, with the remaining 34.1% primarily from CCl4, CH3CCl3, and CFC 113 (CCl2FCClF2). CH3Br represented 54% of the total organic bromine. The 95% confidence intervals of the mixing ratios of all but four of the individual compounds were within the range observed in low and mid-latitude mid-troposphere samples. The four compounds with significantly lower mixing ratios at the tropopause were CHCl3, CH2Cl2, CH2Br2, and CH3CCl3. The lower mixing ratios may be due to entrainment of southern hemisphere air during vertical transport in the tropical region and/or to exchange of air across the tropopause between the lower stratosphere and upper troposphere.

Schauffler, S. M.; Heidt, L. E.; Pollock, W. H.; Gilpin, T. M.; Vedder, J. F.; Solomon, S.; Lueb, R. A.; Atlas, E. L.

1993-01-01

248

Measurements of Halogenated Organic Compounds near the Tropical Tropopause  

NASA Technical Reports Server (NTRS)

The amount of organic chlorine and bromine entering the stratosphere have a direct influence on the magnitude of chlorine and bromine catalyzed ozone losses. Twelve organic chlorine species and five organic bromine species were measured from 12 samples collected near the tropopause between 23.8 deg N and 25.3 deg N during AASE 2. The average mixing ratios of total organic chlorine and total organic bromine were 3.50 +/- 0.06 ppbv and 21.1 +/- 0.8 pptv, respectively. CH3Cl represented 15.1% of the total organic chlorine, with CFC 11 (CCl3F) and CFC 12 (CCl2F2) accounting for 22.6% and 28.2%, respectively, with the remaining 34.1% primarily from CCl4, CH3CCl3, and CFC 113 (CCl2FCClF2). CH3Br represented 54% of the total organic bromine. The 95% confidence intervals of the mixing ratios of all but four of the individual compounds were within the range observed in low and mid-latitude midtroposphere samples. The four compounds with significantly lower mixing ratios at the tropopause were CHCl3, CH2Cl2, CH2Br2, and CH3CCl3. The lower mixing ratios may be due to entrainment of southern hemisphere air during vertical transport in the tropical region and/or to exchange of air across the tropopause between the lower stratosphere and upper troposphere.

Schauffler, S. M.; Heidt, L. E.; Pollock, W. H.; Gilpin, T. M.; Vedder, J. F.; Solomon, S.; Leub, R. A.; Atlas, E. L.

1993-01-01

249

REVIEW OF SEPARATION TECHNOLOGIES FOR TREATING PESTICIDE-CONTAMINATED SOIL  

EPA Science Inventory

Pesticide contamination results from manufacturing, improper storage, handling, or disposal of pesticides, and from agricultural processes. Since most pesticides are mixtures of different compounds, selecting a remedy for pesticide-contaminated soils can be a complicated process....

250

A Review of the Tissue Residue Approach for Organic and Organometallic Compounds in Aquatic Organisms  

EPA Science Inventory

This paper reviews the tissue residue approach (TRA) for toxicity assessment as it applies to organic chemicals and some organometallic compounds (tin, mercury, and lead). Specific emphasis was placed on evaluating key factors that influence interpretation of critical body resid...

251

Anthropogenic Organic Compounds in Source and Finished Water from Community Water System Wells in Western and Central Connecticut, 2002-2004  

USGS Publications Warehouse

A water-quality assessment by the U.S. Geological Survey (USGS) determined the occurrence of anthropogenic (manmade) organic compounds (AOCs) in water from 15 community water system (CWS) wells and associated finished drinking water. The study, which focused on water from the unconfined glacial stratified aquifer in western and central Connecticut, was conducted as part of the USGS National Water-Quality Assessment Program (NAWQA) Source Water-Quality Assessment (SWQA) project and included analysis of water samples for 88 volatile organic compounds (VOCs), 120 pesticides, and 50 other anthropogenic organic compounds (OAOCs). During Phase I of the study, 25 AOCs were detected (12 VOCs, 10 pesticides, and 3 OAOCs) in source-water samples collected from 15 CWS wells sampled once from October 2002 to May 2003. Although concentrations generally were low (less than 1 microgram per liter), four compounds were detected at higher concentrations in ground water from four wells. The most frequently occurring AOCs were detected in more than half of the samples and included chloroform (87 percent), methyl tert-butyl ether (MTBE, 80 percent), 1,1,1-trichloroethane (67 percent), atrazine (60 percent), deethylatrazine (60 percent), perchloroethene (PCE, 53 percent), and simazine (53 percent). Trichloroethene (TCE) was detected in 47 percent of samples. Samples generally contained a mixture of compounds ranging from 2 to 19 detected compounds, with an average of 8 detected compounds per sample. During Phase II of the study, 42 AOCs were detected in source-water samples collected from 10 resampled CWS wells or their associated finished water. Trihalomethanes accounted for most of the VOCs detections with all concentrations less than 1 microgram per liter. Chloroform, the most frequently detected VOC, was found in all source-water and all finished-water samples. As with the Phase I samples, other frequently detected VOCs included MTBE, and the solvents 1,1,1-trichloroethane, PCE, and TCE. Triazine herbicides and their degradation products accounted for most of the detected pesticides.

Trombley, Thoams J.; Brown, Craig J.; Delzer, Gregory C.

2007-01-01

252

Biodiversity of volatile organic compounds from five French ferns.  

PubMed

Five French ferns belonging to different families were investigated for volatile organic compounds (VOC) by GC-MS using organic solvent extraction. Fifty-five VOC biosynthesized from the shikimic, lipidic and terpenic pathways including monoterpenes, sesquiterpenes and carotenoid-type compounds were identified. The main volatile compound of Adiantum capillus-veneris L. (Pteridaceae) was (E)-2-decenal with a plastic or "stink bug" odor. The volatile profiles of Athyrium filix-femina (L.) Roth (Woodsiaceae) and Blechnum spicant (L.) Roth (Blechnaceae) showed similarities, with small amounts of isoprenoids and the same main volatile compounds, i.e., 2-phenylethanal (odor of lilac and hyacinth) and 1-octen-3-ol (mushroom-like odor). The main volatile compound of Dryopteris filix-mas (L.) Schott (Dryopteridaceae) was (E)-nerolidol with a woody or fresh bark note. Polyketides, as acylfilicinic acids, were mainly identified in this fern. Oreopteris limbosperma (Bellardi ex. All.) J. Holub (Thelypteridaceae), well-known for its lemon smell, contained the highest biodiversity of VOC. Eighty percent of the volatiles was issued from the terpenic pathway. The main volatiles were (E)-nerolidol, alpha-terpineol, beta-caryophyllene and other minor monoterpenes (for example, linalool, pinenes, limonene, and gamma-terpinen-7-al). It was also the fern with the highest number of carotenoid-type derivatives, which were identified in large amounts. Our results were of great interest underlying new industrial valorisation for ferns based on their broad spectrum of volatiles. PMID:21121267

Fons, Françoise; Froissard, Didier; Bessière, Jean-Marie; Buatois, Bruno; Rapior, Sylvie

2010-10-01

253

Biological organisms as volatile compound detectors: a review.  

PubMed

The detection and identification of volatile compounds is essential to the successful undertaking of numerous forensic analyses. Biological olfactory systems possess the extraordinary ability to not only detect many thousands of distinct volatile compounds (odors) but also to discriminate between them. Whole-organism biological sensors, such as detection canines, have been employed in forensic science as volatile compound detectors for many years. A variety of insects including bees, wasps, and moths, which have also been shown to detect volatile compounds of forensic significance, have been investigated for their potential application in field-based detection systems. While the fundamental aim for many developers of portable instruments is to replicate the remarkable ability of biological olfactory systems, such analytical equipment is yet to possess the detection and discriminatory powers achieved by biological sensors. Recent literature reveals an increasing interest in olfactory receptors - the biological components that impart olfactory ability - for detecting volatile compounds associated with forensically significant substances such as explosives and illicit drugs. This paper reviews the literature regarding the current, and potential future, use of biological organisms as sensors for forensic science applications. PMID:24053870

Leitch, Olivia; Anderson, Alisha; Kirkbride, K Paul; Lennard, Chris

2013-10-10

254

DISTRIBUTION OF HYDROPHOBIC IONOGENIC ORGANIC COMPOUNDS BETWEEN OCTANOL AND WATER: ORGANIC ACIDS  

EPA Science Inventory

The octanol-water distributions of 10 environmentally significant organic acid compounds were determined as a function of aqueous-phase salt concentration (0.05-0.2 M LiCl, NaCl, KCl, CaCl2, or MgCl2) and pH. he compounds were pentachlorophenol 2,3,4,5-tetrachlorophenol, (2,4,5-t...

255

78 FR 24990 - Approval and Promulgation of Implementation Plans; Ohio; Volatile Organic Compound Emission...  

Federal Register 2010, 2011, 2012, 2013

...Implementation Plans; Ohio; Volatile Organic Compound Emission Control Measures for...Implementation Plan (SIP), several volatile organic compound (VOC) rules that were submitted...stationary sources, storage of volatile organic liquids, industrial cleaning...

2013-04-29

256

Group extraction of organic compounds present in liquid samples  

NASA Technical Reports Server (NTRS)

An extraction device is disclosed comprising a tube containing a substantially inert, chemically non-reactive packing material with a large surface area to volume ratio. A sample which consists of organic compounds dissolved in a liquid, is introduced into the tube. As the sample passes through the packing material it spreads over the material's large surface area to form a thin liquid film which is held on the packing material in a stationary state. A particular group or family of compounds is extractable from the sample by passing a particular solvent system consisting of a solvent and selected reagents through the packing material. The reagents cause optimum conditions to exist for the compounds of the particular family to pass through the phase boundary between the sample liquid and the solvent of the solvent system. Thus, the compounds of the particular family are separated from the sample liquid and become dissolved in the solvent of the solvent system. The particular family of compounds dissolved in the solvent, representing an extract, exits the tube together with the solvent through the tube's nozzle, while the rest of the sample remains on the packing material in a stationary state. Subsequently, a different solvent system may be passed through the packing material to extract another family of compounds from the remaining sample on the packing material.

Jahnsen, Vilhelm J. (Inventor)

1976-01-01

257

Natural organic compounds as tracers for biomass combustion in aerosols  

SciTech Connect

Biomass combustion is an important primary source of carbonaceous particles in the global atmosphere. Although various molecular markers have already been proposed for this process, additional specific organic tracers need to be characterized. The injection of natural product organic tracers to smoke occurs primarily by direct volatilization/steam stripping and by thermal alteration based on combustion temperature. The degree of alteration increases as the burn temperature rises and the moisture content of the fuel decreases. Although the molecular composition of organic matter in smoke particles is highly variable, the molecular structures of the tracers are generally source specific. The homologous compound series and biomarkers present in smoke particles are derived directly from plant wax, gum and resin by volatilization and secondarily from pyrolysis of biopolymers, wax, gum and resin. The complexity of the organic components of smoke aerosol is illustrated with examples from controlled burns of temperate and tropical biomass fuels. Burning of biomass from temperate regions (i.e., conifers) yields characteristic tracers from diterpenoids as well as phenolics and other oxygenated species, which are recognizable in urban airsheds. The major organic components of smoke particles from tropical biomass are straight-chain, aliphatic and oxygenated compounds and triterpenoids. The precursor-to-product approach of organic geochemistry can be applied successfully to provide tracers for studying smoke plume chemistry and dispersion.

Simoneit, B.R.T. [Brookhaven National Lab., Upton, NY (United States)]|[Oregon State Univ., Corvallis, OR (United States). Coll. of Oceanic and Atmospheric Sciences; Abas, M.R. bin [Brookhaven National Lab., Upton, NY (United States)]|[Univ. of Malaya, Kuala Lumpur (Malaysia); Cass, G.R. [Brookhaven National Lab., Upton, NY (United States)]|[California Inst. of Tech., Pasadena, CA (United States). Environmental Engineering Science Dept.; Rogge, W.F. [Brookhaven National Lab., Upton, NY (United States)]|[Florida International Univ., University Park, FL (United States). Dept. of Civil and Environmental Engineering; Mazurek, M.A. [Brookhaven National Lab., Upton, NY (United States); Standley, L.J. [Academy of Natural Sciences, Avondale, PA (United States). Stroud Water Research Center; Hildemann, L.M. [Stanford Univ., CA (United States). Dept. of Civil Engineering

1995-08-01

258

Pesticide use in agriculture.  

PubMed Central

During the last three decades, the use of modern organic synthetic pesticides has increased about 40-fold. Total U.S. production, for domestic and expert use, in 1976 was about 1.4 million pounds. Crops receiving the most intensive application of various pesticides were cotton for insecticides, corn for herbicides, and fruits and vegetables for fungicides. Examination of use trends of pesticides indicates that the volume in pounds of herbicides used on crops is increasing, whereas the quantities of insecticides and fungicides remain stable. New chemical classes of compounds such as the synthetic pyrethroid insecticides are being introduced, but are not yet significant in terms of their share of the market. The increased usage of pesticides, together with knowledge of some of their adverse effects, has alerted the public to the need for regulation. To assist in the regulatory decision-making process, emphasis is being placed on benefit-cost analyses. Additional and improved biological inputs and methodologies are needed to provide accurate analyses. PMID:104870

Ridgway, R L; Tinney, J C; MacGregor, J T; Starler, N J

1978-01-01

259

Differential swimming performance of two natricine snakes exposed to a cholinesterase-inhibiting pesticide  

E-print Network

-inhibiting pesticides (i.e., organophos- phates and carbamates) are among the most widely used compounds for pest cholinesterase activity in organisms exposed to organophosphates and carbamates, but such studies provide limited

Hopkins, William A.

260

Identification and Quantification of Volatile Organic Compounds at a Dairy  

NASA Astrophysics Data System (ADS)

Livestock operations in the United States are an escalating environmental concern. The increasing density of livestock within a farm results in an increased emission of odorous gases, which have gained considerable attention by the public in recent years (National Research Council (NRC), 2002). Odorous compounds such as ammonia (NH3), volatile organic compounds (VOC's), and hydrogen sulfide (H2S) were reported to have a major effect on the quality of life of local residents living near livestock facilities (NRC, 2002). There has been little data collected related to identification and quantification of gaseous compounds collected from open stall dairy operations in the United States. The research to be presented identifies and quantifies VOCs produced from a dairy operation that contribute to odor and other air quality problems. Many different VOCs were identified in the air downwind of an open lactating cow stall area and near a waste lagoon at the Washington State University dairy using Gas Chromatography Mass Spectroscopy (GC-MS) analysis techniques. Identified compounds were very diverse and included many alcohols, aldehydes, amines, aromatics, esters, ethers, a fixed gas, halogenated hydrocarbons, hydrocarbons, ketones, other nitrogen containing compounds, sulfur containing compounds, and terpenes. The VOCs directly associated with cattle waste were dependent on ambient temperature, with the highest emissions produced during the summer months. Low to moderate wind speeds were ideal for VOC collection. Concentrations of quantified compounds were mostly below odor detection thresholds found in the literature, however the combined odor magnitude of the large number of compounds detected was most likely above any minimum detection threshold.

Filipy, J.; Mount, G.; Westberg, H.; Rumburg, B.

2003-12-01

261

Factors influencing degradation of pesticides in soil.  

PubMed

Degradation and sorption of six acidic pesticides (2,4-D, dicamba, fluroxypyr, fluazifop-P, metsulfuron-methyl, and flupyrsulfuron-methyl) and four basic pesticides (metribuzin, terbutryn, pirimicarb, and fenpropimorph) were determined in nine temperate soils. Results were submitted to statistical analyses against a wide range of soil and pesticide properties to (i) identify any commonalities in factors influencing rate of degradation and (ii) determine whether there was any link between sorption and degradation processes for the compounds and soils studied. There were some marked differences between the soils in their ability to degrade the different pesticides. The parameters selected to explain variations in degradation rates depended on the soil-pesticide combination. The lack of consistent behavior renders a global approach to prediction of degradation unrealistic. The soil organic carbon content generally had a positive influence on degradation. The relationship between pH and degradation rates depended on the dominant mode of degradation for each pesticide. There were positive relationships between sorption and rate of degradation for metsulfuron-methyl, pirimicarb, and all acidic pesticides considered together (all P < 0.001) and for dicamba and all bases considered together (P < 0.05). No relationship between these processes was observed for the remaining seven individual pesticides. PMID:17488087

Kah, Melanie; Beulke, Sabine; Brown, Colin D

2007-05-30

262

Transpacific and regional atmospheric transport of anthropogenic semivolatile organic compounds to Cheeka Peak Observatory during the spring of 2002  

NASA Astrophysics Data System (ADS)

Ambient high-volume (hi-vol) air samples were collected between 15 March and 30 May 2002, at Cheeka Peak Observatory (CPO), located on the tip of the Olympic Peninsula, Washington State. This sampling campaign was in conjunction with the Intercontinental Transport and Chemical Transformation 2002 (ITCT 2K2) campaign and the Photochemical Ozone Budget of the Eastern North Pacific Atmosphere 2 (PHOEBA2) experiment. The anthropogenic semivolatile organic compounds (SOCs) measured during this time period included polycyclic aromatic hydrocarbons (PAHs) and various U.S. current-use and historical-use pesticides. The total PAH concentration ranged from 0.480 to 4.49 ng/m3, which is comparable to other remote sites throughout the globe. Ten pesticides (hexachlorobenzene, dacthal, chlorothalonil, heptachlor, trans-nonachlor, cis-nonachlor, endosulfan I, triallate, trifluralin, and mirex) were also measured, and their concentrations (0.104-57.0 pg/m3) were comparable to other remote sites and less than agricultural areas. Gas-phase/particle-phase partitioning was explored, with significant correlation to temperature found with endosulfan I and retene and the possible relationship at CPO of low TSP concentration and the concentration of nonexchangeable compounds in the particle phase. Principal component analysis, as well as a t-test, showed that there were elevated concentrations of anthropogenic SOCs measured during possible transpacific events on 15-16 March, 27-28 March, and 22-23 April 2002 that were identified using the GEOS-CHEM model. The potential sources of these compounds at CPO were determined using diagnostic ratios of their concentrations, back trajectories calculated using Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT4), local meteorological conditions, and U.S. pesticide use data. Additional data are needed to confirm the sources of anthropogenic SOCs at CPO during regional and transpacific atmospheric transport events.

Killin, Robert K.; Simonich, Staci L.; Jaffe, Daniel A.; Deforest, Cindy L.; Wilson, Glenn R.

2004-12-01

263

Monitoring of heavy metal and organic compound levels along the Eastern Aegean coast with transplanted mussels.  

PubMed

Within the framework of the MYTITURK project, heavy metals and organic compounds contaminations were assessed in transplanted mussels in eight different bays from the Eastern Aegean coast. Izmir Bay, Canakkale Strait entrance, Saros and Candarli Bay were defined low pollution extent according to Principal Component Analysis taking into metal accumulation. PAHs (Polycyclic Aromatic Hydrocarbons) levels in the range of 29.4-64.2 ng g(-1) (dry weight) indicated that PAH contamination level classified as low along the Aegean coast. Concentrations of Aroclor1254 and 1260 were higher in transplanted mussels from Canakkale Strait Outlet due to industrial activities was originated from Marmara Sea. The organochlorinated pesticides such as heptachlor (<0.4 ng g(-1)), aldrin (<0.30 ng g(-1)), dieldrin (<0.75 ng g(-1)), endrin (<2.3 ng g(-1)) concentrations were homogeneous however, HCB (Hexachlorobenzene) and lindane concentrations were found undetectable level along the coast. DDE/DDT ratio in the caged mussels form Gulluk and Gokova Bay indicated recent DDT (Dikloro difenil trikloroethan) usage in these areas. The residues of organochlorinated compounds in transplanted mussels confirm the long persistence of DDTs. According to world health authorities, the concentration of heavy metals in mussels for the study area can generally be considered not to be at levels posing a health risk except Zn. The levels of POPs indicated that transplanted mussels have a lack of risk for the human health. PMID:23972908

Kucuksezgin, Filiz; Pazi, Idil; Yucel-Gier, Guzel; Akcali, Baris; Galgani, François

2013-11-01

264

Identification of volatile organic compounds in flowers of Astragalus lagopoides.  

PubMed

Composition of volatile organic compounds (VOCs) in flowers of Astragalus lagopoides was studied using a hydrodistillation extraction procedure coupled with gas chromatography-mass spectrometry. The analyses allowed the identification of a number of 25 compounds, among which the presence of several bioactive aromatic derivatives such as guaiacol, eugenol, linalool, ?- and 4-terpineol as well as nerol was attention-grabbing. Moreover, some other compounds like cyclohexane, 2-bromoethyl with repellent function also appeared to be present in the flower. As a result, the floral VOCs profile of A. lagopoides might reflect an adaptation to attract specialised pollinator insects. These findings provide important information for advances in understanding the ecological and evolutionary perspectives of pollination biology of the giant genus Astragalus. PMID:21878004

Movafeghi, Ali; Delazar, Abbas; Amini, Majid; Asnaashari, Solmaz

2012-01-01

265

Optical D-fiber-based volatile organic compound sensor  

NASA Astrophysics Data System (ADS)

A fiber-optic sensor used to detect volatile organic compounds is described. The sensor consists of a single-mode D-fiber with a 2.5 ?m polydimethylsiloxane layer. The layer is applied to the fiber flat after removal of a section of the fiber's cladding to increase evanescent interaction of the light with the layer. Absorption of volatile organic compounds into the polymer alters the refractive index of the layer, resulting in a birefringent change of the fiber. This change is observed as a shift in polarization of the light carried by the fiber. The sensor has a short length of 3 cm and a response time of around 1 s. The sensor is naturally reversible and gives an exponential response for gas and liquid concentrations of dichloromethane and acetone, respectively.

Gordon, John D.; Lowder, Tyson L.; Selfridge, Richard H.; Schultz, Stephen M.

2007-11-01

266

Organic compounds assessed in Chattahoochee River water used for public supply near Atlanta, Georgia, 2004-05  

USGS Publications Warehouse

An investigation by the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Program characterized the occurrence of 266 organic compounds in source water and finished water from the Chattahoochee River, which is the main water-supply source for the Atlanta metropolitan area. Source water is stream water collected at a surface-water intake prior to water treatment, and finished water is water that has passed through treatment processes prior to distribution. Samples were collected approximately monthly during 2004-05 and included 15 paired source-water and finished-water samples. Samples were collected during winter-spring high flow and summer-fall low flow, but storm events were not targeted during this Source Water-Quality Assessment (SWQA) study. Samples were analyzed for pesticides and degradates, gasoline hydrocarbons, solvents, disinfection by-products, personal care and domestic-use products, and other organic compounds. Community water systems are required to monitor regulated organic compounds under the Safe Drinking Water Act of 1996 (U.S. Environmental Protection Agency, 1998); however, most compounds included in this study are not regulated by Federal drinking-water standards (U.S. Environmental Protection Agency, 2007a). The Chattahoochee River study is part of an ongoing NAWQA investigation of community water systems across the United States. Additional details about the national study are given in Carter and others (2007).

Hughes, W. Brian; Younker, Cristal L.

2011-01-01

267

Sugar-Related Organic Compounds in Carbonaceous Meteorites  

NASA Technical Reports Server (NTRS)

Sugars and related polyols are critical components of all organisms and may have been necessary for the origin of life. To date, this class of organic compounds had not been definitively identified in meteorites. This study was undertaken to determine if polyols were present in the early Solar System as constituents of carbonaceous meteorites. Results of analyses of the Murchison and Murray meteorites indicate that formaldehyde and sugar chemistry may be responsible for the presence of a variety of polyols. We conclude that polyols were present on the early Earth through delivery by asteroids and possibly comets.

Cooper, G.; Kimmich, N.; Belisle, W.; Sarinana, J.; Brabham, K.; Garrel, L.; DeVincenzi, Donald L. (Technical Monitor)

2001-01-01

268

Trees and VOCs: Measuring volatile organic compounds from urban forests  

NSDL National Science Digital Library

This web site describes a research project to measure volatile organic compounds emitted from species of trees and shrubs found in urban areas. Topics include a description of the project and a section on trees and air quality. A page updated each month or so reports field and lab work on the project. There is also a glossary, profiles of community partners, and profiles of the scientists and students involved in the project.

Institute of Arctic and Alpine Research (INSTAAR) at the University of Colorado-Boulder

269

Control of spider mites on cotton by organic sulphur compounds  

E-print Network

COMTBOL OF SPIDER MITES ON COTTON BY ORGANIC SULPHUR COMPOUNDS A Dissertation Bor CHARLES EDWARD KING Approved as to style and content lay* (Chairman of Committee) 10 (Head of Dwpartaent or Student Advisor) CONTROL OF SPIDER MITES ON COTTON... of two species of spider mites using 8 gallons of spray per acre. . 57 10. Results of laboratory ovicidal tests for control of two species of spider mites using 100 gallons of spray per acre.................................................. 59 11...

King, Charles Edward

2013-10-04

270

Artificial Neural Network Electronic Nose for Volatile Organic Compounds  

Microsoft Academic Search

Advanced microsystems that include, sensors, interface-circuits, and pattern-recognition integrated monolithically or in a hybrid module are needed for civilian, military, and space applications. These include: automotive, medical applications, environmental engineering, and manufacturing automation. ASICs with Artificial Neural Networks (ANN) are considered in this paper, with the objective of recognizing air-borne volatile organic compounds, especially alcohols, ethers, esters, halocarbons, NH3, NO2,

Hoda S. Abdel-aty-zohdy

1998-01-01

271

DEVELOPMENT OF OZONE REACTIVITY SCALES FOR VOLATILE ORGANIC COMPOUNDS  

Microsoft Academic Search

Methods for ranking photochemical ozone formation reactivities of volatile organic compounds(VOCs) are discussed. Photochemical mechanisms for the atmospheric reactions of 118 VOCs were usedto calculate their effects on ozone formation under various NO x conditions in model scenarios representing39 different urban areas. Their effects on ozone were used to derive 18 different ozone reactivity scales,one of which is the Maximum

William P. L. Carter

1994-01-01

272

Antarctic macroalgae — Sources of volatile halogenated organic compounds  

Microsoft Academic Search

Twenty-eight different species of Antarctic macroalgae were collected from December 1991 to February 1992 at King George Island, South Shetlands, and investigated for their release of volatile halogenated organic compounds (VHOCs). Dibromomethane, bromoform, dibromochloromethane, bromodichloromethane, diiodomethane and chloroiodomethane were identified and their rates of release determined. For the first time the release of 1,2-dibromoethane from macroalgae is reported. Of all

Frank Laturnus; Christian Wiencke; Heinz Klöser

1996-01-01

273

Degradation of volatile organic compounds with thermally activated persulfate oxidation  

Microsoft Academic Search

This study investigated the extent and treatability of the degradation of 59 volatile organic compounds (VOCs) listed in the EPA SW-846 Method 8260B with thermally activated persulfate oxidation. Data on the degradation of the 59 VOCs (in mixture) reacted with sodium persulfate in concentrations of 1gl?1 and 5gl?1 and at temperatures of 20°C, 30°C, and 40°C were obtained. The results

Kun-Chang Huang; Zhiqiang Zhao; George E. Hoag; Amine Dahmani; Philip A. Block

2005-01-01

274

Removal of volatile organic compound by activated carbon fiber  

Microsoft Academic Search

Experiments were carried out to study adsorption\\/desorption of volatile organic compound (VOC) on the activated carbon fiber (ACF) under dynamic conditions. The primary objective was to experimentally demonstrate the suitability of ACF in effectively adsorbing VOCs from inert gaseous stream under varying operating conditions, and compare its performance vis-à-vis that of the other commercially available adsorbents, such as granular activated

Debasish Das; Vivekanand Gaur; Nishith Verma

2004-01-01

275

Airborne concentrations of volatile organic compounds in neonatal incubators  

Microsoft Academic Search

Objective:To identify and quantify airborne volatile organic compounds (VOCs) inside neonatal incubators during various modes of operation within the neonatal intensive care unit (NICU) environment.Study Design:Air samples were taken from 10 unoccupied incubators in four operational settings along with ambient air samples using air sampling canisters. The samples were analyzed following EPA TO-15 using a Tekmar AutoCan interfaced to Agilent

P Prazad; D R Cortes; B L Puppala; R Donovan; S Kumar; A Gulati

2008-01-01

276

Water Pollution: Organic Compounds in the Charles River, Boston  

Microsoft Academic Search

The major lipophilic organic compounds present in water collected during November and December 1971 from the Charles River Basin (Boston) are as follows: normal alkanes (C15 to C31), alkyl naphthalenes, alkyl anthracenes or phenanthrenes, pyrene, fluoranthene, dibutyl phthalate, and di(2-ethylhexyl) phthalate. The concentration of the naphthalenes (determined by liquid chromatography) correlates with the effective storm-water runoff content of the river.

Ronald A. Hites; K. Biemann

1972-01-01

277

Solubility of volatile organic compounds in aqueous ammonia solution  

Microsoft Academic Search

The Ostwald solubility coefficient, L of 17 volatile organic compounds (VOCs) from the gas phase into water and dilute aqueous ammonia solutions was determined by the equilibrium partitioning in closed system-solid phase micro extraction (EPICS-SPME) method at 303K and at 0–2.5moldm?3 ammonia concentrations. Ammonia increased the solubility of all VOCs nearly linearly, but to a different extent. The difference in

Miklós Görgényi; Jo Dewulf; Herman Van Langenhove; Zoltán Király

2005-01-01

278

Identification and quantification of volatile organic compounds from a dairy  

NASA Astrophysics Data System (ADS)

Volatile organic compounds (VOCs) that contribute to odor and air quality problems have been identified from the Washington State University Knott Dairy Farm using gas chromatography-mass spectroscopy (GC-MS). Eighty-two VOCs were identified at a lactating cow open stall and 73 were detected from a slurry wastewater lagoon. These compounds included alcohols, aldehydes, ketones, esters, ethers, aromatic hydrocarbons, halogenated hydrocarbons, terpenes, other hydrocarbons, amines, other nitrogen containing compounds, and sulfur-containing compounds. The concentration of VOCs directly associated with cattle waste increased with ambient air temperature, with the highest concentrations present during the summer months. Concentrations of most detected compounds were below published odor detection thresholds. Emission rates of ethanol (1026±513 ?g cow -1 s -1) and dimethyl sulfide (DMS) (13.8±10.3 ?g cow -1 s -1) were measured from the lactating stall area using an atmospheric tracer method and concentrations were plotted using data over a 2-year period. Emission rates of acetone (3.03±0.85 ng cow -1 s -1), 2-butanone (145±35 ng cow -1 s -1), methyl isobutyl ketone (3.46±1.11 ng cow -1 s -1), 2-methyl-3-pentanone (25.1±8.0 ng cow -1 s -1), DMS (2.19±0.92 ng cow -1 s -1), and dimethyl disulfide (DMDS) (16.1±3.9 ng cow -1 s -1) were measured from the slurry waste lagoon using a laboratory emission chamber.

Filipy, Jenny; Rumburg, Brian; Mount, George; Westberg, Hal; Lamb, Brian

279

Nonaqueous and aqueous-organic media for the enantiomeric separations of neutral organophosphorus pesticides by CE.  

PubMed

The enantiomeric separation of some poorly water-soluble organophosphorus pesticides (OPs) has been investigated using nonaqueous solvent and aqueous-organic solvent systems. In this work, sodium cholate (SC) either with SDS or gamma-CD was used to achieve enantiomeric separations of four neutral and poorly water-soluble OPs, i.e., profenofos, prothiofos, sulprofos, and pyraclofos. Electrophoretic medium consisted of a mixture of methanol (MeOH) with ACN (4:1 v/v) or a mixture of MeOH with H(2)O and ACN (5:4:1 v/v/v). On one hand, NACE was applied for enantiomeric separation of pyraclofos using a large amount of chiral and achiral surfactants (SC and SDS). On the other hand, H(2)O was added to act as a solvent additive to increase the solubility of gamma-CD in the organic solvents such as MeOH and ACN, in which the solubility of gamma-CD was very low. The presence of H(2)O was found to be particularly useful for the enantiomeric separation of profenofos, prothiofos, and sulprofos. In this way, the range of application of the neutral CDs in CE has been extended. In addition, SC was used as the only electrolyte. The proposed method has been applied for the analysis of soil samples. PMID:17592615

Huang, Lu; Lin, Jinming; Xu, Liangjun; Chen, Guonan

2007-08-01

280

Speciation of volatile organic compounds from poultry production  

NASA Astrophysics Data System (ADS)

Volatile organic compounds (VOCs) emitted from poultry production are leading source of air quality problems. However, little is known about the speciation and levels of VOCs from poultry production. The objective of this study was the speciation of VOCs from a poultry facility using evacuated canisters and sorbent tubes. Samples were taken during active poultry production cycle and between production cycles. Levels of VOCs were highest in areas with birds and the compounds in those areas had a higher percentage of polar compounds (89%) compared to aliphatic hydrocarbons (2.2%). In areas without birds, levels of VOCs were 1/3 those with birds present and compounds had a higher total percentage of aliphatic hydrocarbons (25%). Of the VOCs quantified in this study, no single sampling method was capable of quantifying more than 55% of compounds and in several sections of the building each sampling method quantified less than 50% of the quantifiable VOCs. Key classes of chemicals quantified using evacuated canisters included both alcohols and ketones, while sorbent tube samples included volatile fatty acids and ketones. The top five compounds made up close to 70% of VOCs and included: 1) acetic acid (830.1 ?g m -3); 2) 2,3-butanedione (680.6 ?g m -3); 3) methanol (195.8 ?g m -3); 4) acetone (104.6 ?g m -3); and 5) ethanol (101.9 ?g m -3). Location variations for top five compounds averaged 49.5% in each section of the building and averaged 87% for the entire building.

Trabue, Steven; Scoggin, Kenwood; Li, Hong; Burns, Robert; Xin, Hongwei; Hatfield, Jerry

2010-09-01

281

Results of the monitoring program of pesticide residues in organic food of plant origin in Lombardy (Italy).  

PubMed

Organic agriculture, with its restrictions on the use of synthetic chemical inputs, seems to offer a low-residue alternative to conventional methods. In Europe, the Council Regulation n. 2092/91/EEC regulates the production and trade of organic products and foodstuffs; national and regional legislation in Italy gives specific guidance on the surveillance of organic agriculture. However, monitoring of specific chemical residues in organic foodstuffs is part of the regular controls on food, aiming to safeguard consumer's health. Monitoring programs are coordinated at the national level by the Ministry of Health and at local level by Regional authorities. In Lombardy, in accordance with the provisions of the General Directorate of Health of the Region and under the supervision of the 15 Local Health Units, a monitoring program of pesticide residues in food of plant origin is undertaken every year. The International Centre for Pesticides and Health Risk Prevention (ICPS), on behalf of the General Directorate of Health of the Region of Lombardy, has been collecting and elaborating the data resulting from the analysis of food samples, carried out by the local laboratories. During the period 2002-2005, a total of 3508 samples food of plant origin were analyzed for pesticide residues, among which were 266 samples of organic farming products. Commodities were classified into groups (citrus fruits, legumes, vegetables, potatoes, processed products, cereals, and fruit other than citrus) and the outcomes of the analyses were reported by year, origin of the sample and presence/absence of pesticide residues. Results showed that the vast majority of organic farming products were in conformity with the relevant legislation and did not contain detectable pesticide residues. A limited amount of samples had residues at concentration below the Maximum Residue Limit (MRL). Only in one sample the residue level was above the MRL, however it did not pose a concern for public health, as demonstrated by the outcomes of dietary risk assessment. Organic fruits and vegetables can be expected to contain fewer agrochemical residues than conventionally grown alternatives. There is a widespread belief that organic agriculture products are safer and healthier than conventional foods. It is difficult to come to conclusions, but what should be made clear to the consumer is that "organic" does not automatically equal "safe". In the absence of adequate comparative data, additional studies in this area of research are required. PMID:17763041

Tasiopoulou, Stavroula; Chiodini, Alessandro M; Vellere, Francesca; Visentin, Sara

2007-01-01

282

Significance of urban and agricultural land use for biocide and pesticide dynamics in surface waters  

Microsoft Academic Search

Biocides and pesticides are designed to control the occurrence of unwanted organisms. From their point of application, these substances can be mobilized and transported to surface waters posing a threat to the aquatic environment. Historically, agricultural pesticides have received substantially more attention than biocidal compounds from urban use, despite being used in similar quantities.This study aims at improving our understanding

I. K. Wittmer; H.-P. Bader; R. Scheidegger; H. Singer; A. Lück; I. Hanke; C. Carlsson; C. Stamm

2010-01-01

283

Biodegradation of organic compounds in vadose zone and aquifer sediments  

SciTech Connect

The microbial processes that occur in the subsurface under a typical Midwest agricultural soil were studied. A 26-m bore was installed in November of 1988 at a site of the Purdue University Agronomy Research Center. Aseptic collections of soil materials were made at 17 different depths. Physical analysis indicated that the site contained up to 14 different strata. The site materials were primarily glacial tills with a high carbonate content. The N,P, and organic C contents of sediments tended to decrease with depth. Ambient water content was generally less than the water content, which corresponds to a -0.3-bar equivalent. No pesticides were detected in slurry incubations of up to 128 days. The sorption of atrazine and metolachlor was correlated with the clay content of the sediments. Microbial biomass (determined by direct microscopic count, viable count, and phospholipid assay) in the tills was lower than in either the surface materials or the aquifer located at 25 m. The biodegradation of glucose and phenol occurred rapidly and without a lag in samples from the aquifer capillary fringe, saturated zone, and surface soils. In contrast, lag periods and smaller biodegradation rates were found in the till samples. Subsurface sediments are rich in microbial numbers and activity. The most active strata appear to be transmissive layers in the saturated zone. This implies that the availability of water may limit activity in the profile.

Konopka, A.; Turco, R. (Purdue Univ., West Lafayette, Indiana (USA))

1991-08-01

284

Emissions of volatile organic compounds and carbonyl compounds from residential coal combustion in China  

Microsoft Academic Search

Emissions of volatile organic compounds (VOCs) and carbonyls from residential coal combustion of five coals with different\\u000a maturities were studied in a simulated room. The coals were burned in form of honeycomb briquettes in a domestic coal stove,\\u000a one of the most common fuel\\/stove combinations in China. Through a dilution system, VOCs and carbonyls samples were collected\\u000a by canisters and

Yan-li Feng; Bin Xiong; Cui-cui Mu; Ying-jun Chen

2010-01-01

285

Characterisation of polar organic compounds in fog water  

NASA Astrophysics Data System (ADS)

In this paper the results of a systematic liquid chromatographic investigation are described to characterise water-soluble organic compounds in fog. A diode array detector is used to record the UV spectrum of the components during separation and a mass spectrometer is applied to obtain information on the ion masses of the constituents. The combination of UV and mass spectra reveal that the organic carbon content of fog water is distributed among a great number of acidic compounds which have polar functional groups and polyconjugated systems absorbing up to 500 nm. Due to the complexity of the organic fraction in fog water an unresolved hump of ions was recorded by the mass spectrometer from m/ z=100-600 the most intense peaks being detected around m/ z=200-250. Tannin and fulvic acid were also examined under the same conditions. In terms of complexity and ion distribution the mass spectrum of the organic fraction was similar to that of a fulvic acid reference material rather than to that of tannin.

Kiss, Gyula; Varga, Bálint; Gelencsér, András; Krivácsy, Zoltán; Molnár, Ágnes; Alsberg, Tomas; Persson, Linn; Hansson, Hans-Christen; Cristina Facchini, Maria

286

Simulation of Comet Impact and Survivability of Organic Compounds  

SciTech Connect

Comets have long been proposed as a potential means for the transport of complex organic compounds to early Earth. For this to be a viable mechanism, a significant fraction of organic compounds must survive the high temperatures due to impact. We have undertaken three-dimensional numerical simulations to track the thermodynamic state of a comet during oblique impacts. The comet was modeled as a 1-km water-ice sphere impacting a basalt plane at 11.2 km/s; impact angles of 15{sup o} (from horizontal), 30{sup o}, 45{sup o}, 65{sup o}, and 90{sup o} (normal impact) were examined. The survival of organic cometary material, modeled as water ice for simplicity, was calculated using three criteria: (1) peak temperatures, (2) the thermodynamic phase of H{sub 2}O, and (3) final temperature upon isentropic unloading. For impact angles greater than or equal to 30{sup o}, no organic material is expected to survive the impact. For the 15{sup o} impact, most of the material survives the initial impact and significant fractions (55%, 25%, and 44%, respectively) satisfy each survival criterion at 1 second. Heating due to deceleration, in addition to shock heating, plays a role in the heating of the cometary material for nonnormal impacts. This effect is more noticeable for more oblique impacts, resulting in significant deviations from estimates using scaling of normal impacts. The deceleration heating of the material at late times requires further modeling of breakup and mixing.

Liu, B T; Lomov, I N; Blank, J G; Antoun, T H

2007-07-18

287

Characteristics of the volatile organic compounds -- Arid Integrated Demonstration Site  

SciTech Connect

The Volatile Organic Compounds -- Arid Integrated Demonstration Program (VOC-Arid ID) is targeted at demonstration and testing of technologies for the evaluation and cleanup of volatile organic compounds and associated contaminants at arid DOE sites. The initial demonstration site is an area of carbon tetrachloride (CCl{sub 4}) contamination located near the center of the Hanford Site. The movement of CCl{sub 4} and other volatile organic contaminants in the subsurface is very complex. The problem at the Hanford Site is further complicated by the concurrent discharge of other waste constituents including acids, lard oil, organic phosphates, and transuranic radionuclides. In addition, the subsurface environment is very complex, with large spatial variabilities in hydraulic properties. A thorough understanding of the problem is essential to the selection of appropriate containment, retrieval, and/or in situ remedial technologies. The effectiveness of remedial technologies depends on knowing where the contaminants are, how they are held up in a given physical and chemical subsurface environment; and knowing the physical, chemical, and microbiological changes that are induced by the various remedial technologies.

Last, G.V.; Lenhard, R.J.; Bjornstad, B.N.; Evans, J.C.; Roberson, K.R.; Spane, F.A.; Amonette, J.E.; Rockhold, M.L.

1991-10-01

288

Biodegradable material for the absorption of organic compounds and nanoparticles.  

PubMed

Contaminants in water streams, in the form of oily/organic phases or nanoparticles, affect a large variety of activities, from laboratory practice up to environmental systems. To date, a large number of materials for the absorption and retention of these pollutants have been developed. Such materials, however, rarely conjugate high oil uptake, nanoparticle sequestration, biodegradability, and cost effectiveness simultaneously. In this work, we exploited the structural properties of dermal collagen networks and simple chemical manipulations to fabricate an original material that proved effective in separating water from organic and nanoparticulated contaminants. Our material is reusable, biodegradable, safe, and cost-effective and shows a high absorptive capacity of a large variety of organic compounds; it is also able to capture metallic nanoparticles. These features allow our material to effectively separate water from oily/nanoparticulate phases, thus making it an appropriate absorber for chemical processes and environmental protection. PMID:25054655

Ortega, Francisco J; Ventre, Maurizio; Netti, Paolo A

2014-09-01

289

Pesticide Exposure, Safety Issues, and Risk Assessment Indicators  

PubMed Central

Pesticides are widely used in agricultural production to prevent or control pests, diseases, weeds, and other plant pathogens in an effort to reduce or eliminate yield losses and maintain high product quality. Although pesticides are developed through very strict regulation processes to function with reasonable certainty and minimal impact on human health and the environment, serious concerns have been raised about health risks resulting from occupational exposure and from residues in food and drinking water. Occupational exposure to pesticides often occurs in the case of agricultural workers in open fields and greenhouses, workers in the pesticide industry, and exterminators of house pests. Exposure of the general population to pesticides occurs primarily through eating food and drinking water contaminated with pesticide residues, whereas substantial exposure can also occur in or around the home. Regarding the adverse effects on the environment (water, soil and air contamination from leaching, runoff, and spray drift, as well as the detrimental effects on wildlife, fish, plants, and other non-target organisms), many of these effects depend on the toxicity of the pesticide, the measures taken during its application, the dosage applied, the adsorption on soil colloids, the weather conditions prevailing after application, and how long the pesticide persists in the environment. Therefore, the risk assessment of the impact of pesticides either on human health or on the environment is not an easy and particularly accurate process because of differences in the periods and levels of exposure, the types of pesticides used (regarding toxicity and persistence), and the environmental characteristics of the areas where pesticides are usually applied. Also, the number of the criteria used and the method of their implementation to assess the adverse effects of pesticides on human health could affect risk assessment and would possibly affect the characterization of the already approved pesticides and the approval of the new compounds in the near future. Thus, new tools or techniques with greater reliability than those already existing are needed to predict the potential hazards of pesticides and thus contribute to reduction of the adverse effects on human health and the environment. On the other hand, the implementation of alternative cropping systems that are less dependent on pesticides, the development of new pesticides with novel modes of action and improved safety profiles, and the improvement of the already used pesticide formulations towards safer formulations (e.g., microcapsule suspensions) could reduce the adverse effects of farming and particularly the toxic effects of pesticides. In addition, the use of appropriate and well-maintained spraying equipment along with taking all precautions that are required in all stages of pesticide handling could minimize human exposure to pesticides and their potential adverse effects on the environment. PMID:21655127

Damalas, Christos A.; Eleftherohorinos, Ilias G.

2011-01-01

290

Effects of the benzoxazolinone BOA, selected degradation products and structure related pesticides on soil organisms.  

PubMed

The benzoxazolinone BOA and the degradation products APO, AAPO and HPAA, as well as four structure related compounds to BOA, were tested for their lethal and sublethal effects on the collembola Folsomia candida and on the carabid beetle Poecilus cupreus applying validated standard laboratory methods. According to the results of the recommended risk assessment for plant protection products (EPPO, 2003), BOA and its structure related compounds carbendazim, benoxacor and benazolin (and additionally the formulated product Cresopur) were classified as low risk compounds for both test organisms. Phosalone was of high risk for F. candida. APO, AAPO and HPAA were of medium risk for F. candida, but were rated as low risk compounds for P. cupreus at the tested rates of about 2 mg/kg substrate. However, as the BOA degradation products have been found to occur at field rates below 0.2 mg/kg substrate or are often even not detectable, it is assumed that their potential risk for both non-target soil organisms in the field will be acceptable. PMID:16344919

Coja, Tamara; Idinger, Jacqueline; Blümel, Sylvia

2006-02-01

291

Occurrence and accumulation of pesticides and organic contaminants in river sediment, water and clam tissues from the San Joaquin River and tributaries, California  

USGS Publications Warehouse

A study was conducted in 1992 to assess the effects of anthropogenic activities and land use on the water quality of the San Joaquin River and its major tributaries. This study focused on pesticides and organic contaminants, looking at distributions of contaminants in water, bed and suspended sediment, and the bivalve Corbicula fluminea. Results indicated that this river system is affected by agricultural practices and urban runoff. Sediments from Dry Creek contained elevated concentrations of polycyclic aromatic hydrocarbons (PAHs), possibly derived from urban runoff from the city of Modesto; suspended sediments contained elevated amounts of chlordane. Trace levels of triazine herbicides atrazine and simazine were present in water at most sites. Sediments, water, and bivalves from Orestimba Creek, a westside tributary draining agricultural areas, contained the greatest levels of DDT (1,1,1-trichloro-2-2-bis[p-chlorophenyl]ethane), and its degradates DDD (1,1-dichloro-2,2-bis[p-chlorophenyl]ethane), and DDE (1,1-dichloro-2,2- bis[p-chlorophenyl]ethylene). Sediment adsorption co efficients (K(oc)), and bioconcentration factors (BCF) in Corbicula of DDT, DDD, and DDE at Orestimba Creek were greater than predicted values. Streams of the western San Joaquin Valley can potentially transport significant amounts of chlorinated pesticides to the San Joaquin River, the delta, and San Francisco Bay. Organochlorine compounds accumulate in bivalves and sediment and may pose a problem to other biotic species in this watershed.

Pereira, W.E.; Domagalski, J.L.; Hostettler, F.D.; Brown, L.R.; Rapp, J.B.

1996-01-01

292

Transport, behavior, and fate of volatile organic compounds in streams  

USGS Publications Warehouse

Volatile organic compounds (VOCs) are compounds with chemical and physical properties that allow the compounds to move freely between the water and air phases of the environment. VOCs are widespread in the environment because of this mobility. Many VOCs have properties that make them suspected or known hazards to the health of humans and aquatic organisms. Consequently, understanding the processes affecting the concentration and distribution of VOCs in the environment is necessary. The transport, behavior, and fate of VOCs in streams are determined by combinations of chemical, physical, and biological processes. These processes are volatilization, absorption, wet and dry deposition, microbial degradation, sorption, hydrolysis, aquatic photolysis, oxidation, chemical reaction, biocon-centration, advection, and dispersion. The relative importance of each of these processes depends on the characteristics of the VOC and the stream. The U.S. Geological Survey National Water-Quality Assessment Program selected 55 VOCs for study. This article reviews the characteristics of the various processes that could affect the transport, behavior, and fate of these VOCs in streams.

Rathbun, R.E.

2000-01-01

293

Pesticide residues determination in Polish organic crops in 2007-2010 applying gas chromatography-tandem quadrupole mass spectrometry.  

PubMed

A sensitive, accurate and reliable multiresidue method based on the application of gas chromatography-tandem quadrupole mass spectrometry (GC-QqQ-MS/MS) has been established for screening, identification and quantification of a large number of pesticide residues in produce. The method was accredited in compliance with PN-EN ISO/IEC 17025:2005 standard and it was operated under flexible scope as PB-11 method. The flexible scope of accreditation allowed for minor modifications and extension of the analytical scope while using the same analytical technique. During the years 2007-2010, the method was used for the purpose of verification of organic crop production by multiresidue analysis for the presence of pesticides. A total of 528 samples of differing matrices such as fruits, vegetables, cereals, plant leaves and other green parts were analysed, of which 4.4% samples contained pesticide residues above the threshold value of 0.01 mg/kg. A total of 20 different pesticide residues were determined in the samples. PMID:23561134

Walorczyk, Stanis?aw; Dro?d?y?ski, Dariusz; Kowalska, Jolanta; Remlein-Starosta, Dorota; Zió?kowski, Andrzej; Przewo?niak, Monika; Gnusowski, Bogus?aw

2013-08-15

294

A study of pesticide residue levels and insecticide resistance in selected aquatic organisms occurring around the Bryan-College Station agricultural production areas  

E-print Network

populations of mosquitofish, Gambusia affinis (Baird and Girard) was conducted from August, 1970 to January, 1971. The study 1nvolving DDT accumulation in non-target aquatic organisms consisted of selecting bodies of water that were subject to acc1dental... 14 Procedure for bioassay of mosquitofish, Cambusia affinis . 27 Results. Pesticide res1due accumulation in the organisms sampled. . 29 Bioassay of mosqui tofi sh Gambusi a aff1ni s . Discussion 38 43 Pesticide residue accumulation 1n non...

Dziuk, Larry James

2012-06-07

295

Antioxidant combinations of molybdenum complexes and organic sulfur compounds for lubricating oils  

SciTech Connect

An antioxidant additive combination for lubricating oils is prepared by combining (a) a sulfur containing molybdenum compound prepared by reacting an ammonium tetrathiomolybdate, and a basic nitrogen compound, with (b) an organic sulfur compound.

deVries, L.; King, J.M.

1983-09-06

296

Characterization of organochlorine pesticides, brominated flame retardants and dioxin-like compounds in shellfish and eel from Fiji.  

PubMed

This article gives an overview of a range of persistent organic pollutant chemical levels in shellfish (Batissa violacea and Anadara antiquata) species and eel (Gymnothorax flavimarginatus) from Fiji. As there is limited data in published literature to date, this paper reports first data on a range of persistent organic pollutants and highlights the more prominent POP chemicals present in marine biota in Fiji. A significant number of POP chemicals were detected (e.g. 17 PCDD/PCDF, 12dl-PCBs, organochlorine pesticides and brominated flame retardants), the concentrations found were generally low (e.g. parts per billion level). The low levels of contamination are indicative of a low input from long range and short-range transport as well as few local point sources. Also concentrations of POPs in eel and shellfish from Fiji are low in comparison to wild species in other regions and are within acceptable limits for POP chemicals in fish and fishery products set by the European Union. It describes also results of early studies on basic POPs levels in shellfish in several Pacific Island Countries, which generally show relatively low levels. PMID:24568747

Lal, Vincent; Bridgen, Phil; Votadroka, Waisea; Raju, Rupantri; Aalbersberg, William

2014-09-01

297

Volatile organic compounds from a Tuber melanosporum fermentation system.  

PubMed

A total of 59 volatile organic compounds (VOCs) were identified from Tuber melanosporum fermentation: 53 from its fermented mycelia and 32 from the fermentation broth. Alcohol-derived compounds were predominant in both the fermentation mycelia and the broth, although long chain fatty acids and isoprenoids were, for the first time, also found in the mycelia. The intense wine bouquet properties of the broth arose from several specific flavor substances, including sulfur compounds, pyrazines, furans and jasmones. Comparing the VOCs identified in this work with those previously reported, our results are more similar to the composition of the Tuber fruiting-body than previous Tuber fermentations. The composition and accumulation of flavor volatiles (e.g., pyrazines, sulfur compounds, and esters) and major constituents (e.g., 3-methyl-1-butanol and 2-phenylethanol) in this fermentation were significantly influenced by the sucrose concentration in the medium. The obtained information could therefore be useful in applications to convert the flavors of truffle mycelia similar to those of the fruiting-body by optimising the fermentation process. PMID:22980851

Li, Yuan-Yuan; Wang, Guan; Li, Hong-Mei; Zhong, Jian-Jiang; Tang, Ya-Jie

2012-12-15

298

75 FR 24404 - Approval and Promulgation of Air Quality Implementation Plans; Indiana; Volatile Organic Compound...  

Federal Register 2010, 2011, 2012, 2013

...Indiana; Volatile Organic Compound Automobile Refinishing Rules for Indiana AGENCY...Plan (SIP) amendments to Indiana's automobile refinishing rule. These rule revisions...approved volatile organic compound (VOC) automobile refinishing rules to all persons...

2010-05-05

299

75 FR 2090 - Approval and Promulgation of Air Quality Implementation Plans; Indiana; Volatile Organic Compound...  

Federal Register 2010, 2011, 2012, 2013

...Indiana; Volatile Organic Compound Automobile Refinishing Rules for Indiana AGENCY...submitted amendments to Indiana's automobile refinishing rule for approval into its...approved volatile organic compound (VOC) automobile refinishing rules to all persons...

2010-01-14

300

EVALUATION OF CRYOGENIC TRAPPING AS A MEANS FOR COLLECTING ORGANIC COMPOUNDS IN AMBIENT AIR  

EPA Science Inventory

The methodology used in reduced temperature preconcentration of volatile organic compounds has been tested using a prototype automated gas chromatographic system. Mixtures of sixteen volatile organic compounds in humidified zero air were passed through a Nafion tube dryer and the...

301

Odors and volatile organic compounds released from ventilation filters  

NASA Astrophysics Data System (ADS)

Used supply air filters were studied by sensory and chemical methods. In addition, filter dust was examined by thermodesorption/cold trap (TCT) and headspace (HS) devices connected to a GC-MS. The prefilter was the main odor source in the ventilation unit, but when humidifier was turned on odor was released mainly from the fine filter. However, the effect of the relative humidity (RH) was only temporary. At the same time, there was an increase in the concentration of aldehydes after the filters. Aldehydes, carboxylic acids, and nitrogen-containing organic compounds were the main emission products in the thermodesorption analyses of the filter dust. Many of these compounds have low odor threshold values and, therefore, contribute to the odor released from the filters. Especially, the role of aldehydes seems to be important in the odor formation.

Hyttinen, Marko; Pasanen, Pertti; Björkroth, Marko; Kalliokoski, Pentti

302

Molar extinction coefficients of solutions of some organic compounds  

NASA Astrophysics Data System (ADS)

Molar extinction coefficients of aqueous solutions of some organic compounds, viz. formamide (CH_{3}NO), N-methylformamide (C_{2}H_{5}NO), NN-dimethylformamide (C_{3}H_{7}NO), NN-dimethylacetamide (C_{4}H_{9}NO), 1,4-dioxane (C_{4}H_{8}O_{2}), succinimide (C_{4}H_{5}NO_{2}) and solutions of acetamide (C_{2}H_{5}NO) and benzoic acid (C_{7}H_{6}O_{2}) in 1,4-dioxane (C_{4}H_{8}O_{2}) have been determined by narrow beam gamma-ray transmission method at 81, 356, 511, 662, 1173 and 1332 keV. The experimental values of mass attenuation coefficients of these compounds have been used to calculate effective atomic numbers and electron densities. The additivity rule earlier used for aqueous solution has been extended to non-aqueous (1,4-dioxane) solutions.

Singh, Kulwant; Sandhu, G. K.; Lark, B. S.

2004-05-01

303

Bioavailability of pesticides to benthic invertebrates.  

E-print Network

??In agricultural landscapes, pesticides are frequently contaminating nearby aquatic ecosystems. Unlike most other contaminants, pesticides are targeted against specific organism groups, but will also have… (more)

Lundqvist, Anna

2011-01-01

304

Freshwater mussels as biomonitors for organic industrial contaminants and pesticides in the St. Lawrence River.  

PubMed

Native mussels (Elliptio complanata and Lampsilis radiata radiata) were collected from 17 stations in the St. Lawrence River between Lake Ontario and Trois Rivières and from three stations in a major tributary, the Ottawa River, in October, 1985. Mussels were solvent-extracted and analyzed individually by dual capillary column gas chromatography for seven organochlorine pesticides, 11 chlorobenzenes, octachlorostyrene and 63 PCB congeners. Bioconcentration patterns for contaminants in mussel tissues implicated Lake Ontario as the source of Mirex and DDT derivatives to the system and the Grass River as the major source of PCBs. Numbers of PCB congeners in mussels increased from 21-27 in the upper river to 56-59 in the Cornwall/Massena industrial core, mainly due to the appearance of di-, tri- and tetrachlorobiphenyls; an average of 43 congeners persisted as far downstream as Lac Saint-Pierre. Concentrations of most contaminants in mussels from the Ottawa River were 50-75% lower than the lowest values reported for the St. Lawrence River. This study provides information on the origin, bioavailability and persistence of organic contaminants in the St. Lawrence River ecosystem. PMID:2128132

Metcalfe, J L; Charlton, M N

1990-11-01

305

Heterogeneous reactions of volatile organic compounds in the atmosphere  

NASA Astrophysics Data System (ADS)

Volatile organic compounds (VOCs) are of central importance in the atmosphere because of their close relation to air quality and climate change. As a significant sink for VOCs, the fate of VOCs via heterogeneous reactions may explain the big gap between field and model studies. These reactions play as yet unclear but potentially crucial role in atmospheric processes. In order to better evaluate this reaction pathway, we present the first specific review for the progress of heterogeneous reaction studies on VOCs, including carbonyl compounds, organic acids, alcohols, and so on. Our review focuses on the processes for heterogeneous reactions of VOCs under varying experimental conditions, as well as their implications for trace gas and HOx budget, secondary organic aerosol (SOA) formation, physicochemical properties of aerosols, and human health. Finally, we propose the future direction for laboratory studies of heterogeneous chemistry of VOCs that should be carried out under more atmospherically relevant conditions, with a special emphasis on the effects of relative humidity and illumination, the multicomponent reaction systems, and reactivity of aged and authentic particles. In particular, more reliable uptake coefficients, based on the abundant elaborate laboratory studies, appropriate calibration, and logical choice criterion, are urgently required in atmospheric models.

Shen, Xiaoli; Zhao, Yue; Chen, Zhongming; Huang, Dao

2013-04-01

306

Organic Compounds in Running Gutter Brook Water Used for Public Supply near Hatfield, Massachusetts, 2003-05  

USGS Publications Warehouse

The 258 organic compounds studied in this U.S. Geological Survey (USGS) assessment generally are man-made, including pesticides, solvents, gasoline hydrocarbons, personal-care and domestic-use products, and pavement and combustion-derived compounds. Of these 258 compounds, 26 (about 10 percent) were detected at least once among the 31 samples collected approximately monthly during 2003-05 at the intake of a flowthrough reservoir on Running Gutter Brook in Massachusetts, one of several community water systems on tributaries of the Connecticut River. About 81 percent of the watershed is forested, 14 percent is agricultural land, and 5 percent is urban land. In most source-water samples collected at Running Gutter Brook, fewer compounds were detected and their concentrations were low (less than 0.1 micrograms per liter) when compared with compounds detected at other stream sites across the country that drain watersheds that have a larger percentage of agricultural and urban areas. The relatively few compounds detected at low concentrations reflect the largely undeveloped land use at Running Gutter Brook. Despite the absence of wastewater discharge points on the stream, however, the compounds that were detected could indicate different sources and uses (point sources, precipitation, domestic, and agricultural) and different pathways to drinking-water supplies (overland runoff, groundwater discharge, leaking of treated water from distribution lines, and formation during treatment). Six of the 10 compounds detected most commonly (in at least 20 percent of the samples) in source water also were detected commonly in finished water (after treatment but prior to distribution). Concentrations in source and finished water generally were below 0.1 micrograms per liter and always less than humanhealth benchmarks, which are available for about one-half of the compounds detected. On the basis of this screening-level assessment, adverse effects to human health are expected to be negligible (subject to limitations of available humanhealth benchmarks).

Brown, Craig J.; Trombley, Thomas J.

2009-01-01

307

Anthropogenic Organic Compounds in Source Water of Selected Community Water Systems that Use Groundwater, 2002-05  

USGS Publications Warehouse

Source water, defined as groundwater collected from a community water system well prior to water treatment, was sampled from 221 wells during October 2002 to July 2005 and analyzed for 258 anthropogenic organic compounds. Most of these compounds are unregulated in drinking water and include pesticides and pesticide degradates, gasoline hydrocarbons, personal-care and domestic-use products, and solvents. The laboratory analytical methods used in the study have detection levels that commonly are 100 to 1,000 times lower than State and Federal standards and guidelines for protecting water quality. Detections of anthropogenic organic compounds do not necessarily indicate a concern to human health but rather help to identify emerging issues and track changes in occurrence and concentrations over time. Less than one-half (120) of the 258 compounds were detected in at least one source-water sample. Chloroform, in 36 percent of samples, was the most commonly detected of the 12 compounds that were in about 10 percent or more of source-water samples. The herbicides atrazine, metolachlor, prometon, and simazine also were among the commonly detected compounds. The commonly detected degradates of atrazine - deethylatrazine and deisopropylatrazine - as well as degradates of acetochlor and alachlor, generally were detected at concentrations similar to or greater than concentrations of the parent herbicide. The compounds perchloroethene, trichloroethene, 1,1,1-trichloroethane, methyl tert-butyl ether, and cis-1,2-dichloroethene also were detected commonly. The most commonly detected compounds in source-water samples generally were among those detected commonly across the country and reported in previous studies by the U.S. Geological Survey's National Water-Quality Assessment Program. Relatively few compounds were detected at concentrations greater than human-health benchmarks, and 84 percent of the concentrations were two or more orders of magnitude less than benchmarks. Five compounds (perchloroethene, trichloroethene, 1,2-dibromoethane, acrylonitrile, and dieldrin) were detected at concentrations greater than their human-health benchmark. The human-health benchmarks used for comparison were U.S. Environmental Protection Agency Maximum Contaminant Levels (MCLs) for regulated compounds and Health-Based Screening Levels developed by the U.S. Geological Survey in collaboration with the U.S. Environmental Protection Agency and other agencies for unregulated compounds. About one-half of all detected compounds do not have human-health benchmarks or adequate toxicity information to evaluate results in a human-health context. Ninety-four source-water and finished-water (water that has passed through all the treatment processes but prior to distribution) sites were sampled at selected community water systems during June 2004 to September 2005. Most of the samples were analyzed for compounds that were detected commonly or at relatively high concentrations during the initial source-water sampling. The majority of the finished-water samples represented water blended with water from one or more other wells. Thirty-four samples were from water systems that did not blend water from sampled wells with water from other wells prior to distribution. The comparison of source- and finished-water samples represents an initial assessment of whether compounds present in source water also are present in finished water and is not intended as an evaluation of water-treatment efficacy. The treatment used at the majority of the community water systems sampled is disinfection, which, in general, is not designed to remove the compounds monitored in this study. Concentrations of all compounds detected in finished water were less than their human-health benchmarks. Two detections of perchloroethene and one detection of trichloroethene in finished water had concentrations within an order of magnitude of the MCL. Concentrations of disinfection by-products were

Hopple, Jessica A.; Delzer, Gregory C.; Kingsbury, James A.

2009-01-01

308

Ambient gas/particle partitioning. 3. Estimating partition coefficients of apolar, polar, and ionizable organic compounds by their molecular structure.  

PubMed

Equilibrium gas/particle partitioning coefficients of terrestrial aerosols, Kip, are dependent on various intermolecular interactions that can be quantified by experimentally determined compound-specific descriptors. For many compounds of environmental interest, such as emerging contaminants and atmospheric phototransformation products, these compound-specific descriptors are unknown or immeasurable. Often, only the molecular structure is known. Here we present the ability of two computer programs to predict equilibrium partitioning to terrestrial aerosols solely on the basis of molecular structure: COSMOtherm and SPARC. The greatest hurdle with designing such an approach is to identify suitable molecular surrogates to represent the dominating sorbing phases, which for ambient terrestrial aerosols are the water insoluble organic matter (WIOM) phase and the mixed-aqueous phase. For the WI0M phase, hypothetical urban secondary organic aerosol structural units from Kalberer et al. Science 2004, 303, 1659-1662 were investigated as input surrogates, and for the mixed-aqueous phase mildly acidic water was used as a surrogate. Using a validation data set of more than 1400 experimentally determined Kip values for polar, apolar, and ionic compounds ranging over 9 orders of magnitude (including semivolatile compounds such as PCDD/Fs, pesticides, and PBDEs), SPARC and COSMOtherm were generally able to predict Kip values well within an order of magnitude over an ambient range of temperature and relative humidity. This is remarkable as these two models were not fitted or calibrated to any experimental data. As these models can be used for potentially any organic molecule, they are particularly recommended for environmental screening purposes and for use when experimental compound descriptor data are not available. PMID:19368193

Arp, Hans Peter H; Gosses, Kai-Uwe

2009-03-15

309

Volatile organic compounds in the unsaturated zone from radioactive wastes.  

PubMed

Volatile organic compounds (VOCs) are often comingled with low-level radioactive wastes (LLRW), but little is known about subsurface VOC emanations from LLRW landfills. The current study systematically quantified VOCs associated with LLRW over an 11-yr period at the USGS Amargosa Desert Research Site (ADRS) in southwestern Nevada. Unsaturated-zone gas samples of VOCs were collected by adsorption on resin cartridges and analyzed by thermal desorption and GC/MS. Sixty of 87 VOC method analytes were detected in the 110-m-thick unsaturated zone surrounding a LLRW disposal facility. Chlorofluorocarbons (CFCs) were detected in 100% of samples collected. Chlorofluorocarbons are powerful greenhouse gases, deplete stratospheric ozone, and are likely released from LLRW facilities worldwide. Soil-gas samples collected from a depth of 24 m and a horizontal distance 100 m south of the nearest waste-disposal trench contained >60,000 ppbv total VOCs, including >37,000 ppbv CFCs. Extensive sampling in the shallow unsaturated zone (0-2 m deep) identified areas where total VOC concentrations exceeded 5000 ppbv at the 1.5-m depth. Volatile organic compound concentrations exceeded background levels up to 300 m from the facility. Maximum vertical diffusive fluxes of total VOCs were estimated to be 1 g m yr. Volatile organic compound distributions were similar but not identical to those previously determined for tritium and elemental mercury. To our knowledge, this study is the first to characterize the unsaturated zone distribution of VOCs emanating from a LLRW landfill. Our results may help explain anomalous transport of radionuclides at the ADRS and elsewhere. PMID:22751077

Baker, Ronald J; Andraski, Brian J; Stonestrom, David A; Luo, Wentai

2012-01-01

310

Organic marker compounds in surface soils of crop fields from the San Joaquin Valley fugitive dust characterization study  

NASA Astrophysics Data System (ADS)

Fugitive dust from the erosion of arid and fallow land, after harvest and during agricultural activities, can at times be the dominant source of airborne particulate matter. In order to assess the source contributions to a given site, chemical mass balance (CMB) modeling is typically used together with source-specific profiles for organic and inorganic constituents. Yet, the mass balance closure can be achieved only if emission profiles for all major sources are considered. While a higher degree of mass balance closure has been achieved by adding individual organic marker compounds to elements, ions, EC, and organic carbon (OC), major source profiles for fugitive dust are not available. Consequently, neither the exposure of the population living near fugitive dust sources from farm land, nor its chemical composition is known. Surface soils from crop fields are enriched in plant detritus from both above and below ground plant parts; therefore, surface soil dust contains natural organic compounds from the crops and soil microbiota. Here, surface soils derived from fields growing cotton, safflower, tomato, almonds, and grapes have been analyzed for more than 180 organic compounds, including natural lipids, saccharides, pesticides, herbicides, and polycyclic aromatic hydrocarbon (PAH). The major result of this study is that selective biogenically derived organic compounds are suitable markers of fugitive dust from major agricultural crop fields in the San Joaquin Valley. Aliphatic homologs exhibit the typical biogenic signatures of epicuticular plant waxes and are therefore indicative of fugitive dust emissions and mechanical abrasion of wax protrusions from leaf surfaces. Saccharides, among which ?- and ?-glucose, sucrose, and mycose show the highest concentrations in surface soils, have been proposed to be generic markers for fugitive dust from cultivated land. Similarly, steroids are strongly indicative of fugitive dust. Yet, triterpenoids reveal the most pronounced distribution differences for all types of cultivated soils examined here and are by themselves powerful markers for fugitive dust that allow differentiation between the types of crops cultivated. PAHs are also found in some surface soils, as well as persistent pesticides, e.g., DDE, Fosfall, and others.

Rogge, Wolfgang F.; Medeiros, Patricia M.; Simoneit, Bernd R. T.

311

Thermodynamics of Aqueous Organic Sulfur Compounds: A Key to the Organic Geochemistry of Hydrothermal Systems?  

NASA Technical Reports Server (NTRS)

Hydrothermal environments are locations of varied geochemistry due to the disequilibrium between vent fluids and seawater. The disequilibrium geochemistry has been hypothesized to include reactions to synthesize organic compounds. Observations of the organic geochemistry of hydrothermal vent sites has received little attention. Experimental simulations of these environments, however, indicate that organic compounds may have difficulty forming in a purely aqueous environment. On the other hand, thiols. thioesters and disulfides have been implicated as reaction intermediates between CO or CO2 in experiments of carbon reduction in hydrothermal environments as well as in a variety of biological processes and other abiotic reactions (Wachtershauser, 1990, OLEB 20, 173; Heinen and Lauwers, 1996, OLEB 26, 13 1, Huber and Wachtershauser, 1997, Science 276, 245; Russell et al., 1998, in Thermophiles: The keys to molecular evolution and the origin of life?). The reduction of CO2 to thiols, for example, is observed using the FeS-H2S/FeS2 couple to provide the reducing power (see Schoonen et al., 1999, OLEB 29, 5). In addition, the enzyme involved in final stage of methanogenesis, coenzyme-M, is itself a thiol. Thus, organic sulfur compounds may hold the key to the organic chemistry leading to the origin of life at high temperatures. Understanding the biochemical processes of microorganisms that can live to temperatures at least as high as 113 C (Blochl et al., 1996, Extremophiles 1, 14) requires knowledge of the properties of the chemical reactions involved. In order to assess the role of aqueous organic sulfur compounds in hydrothermal organic geochemistry, we have been attempting to determine their thermodynamic properties. We have culled the literature to obtain the properties of organic sulfur compounds. We are able to calculate a number of essential properties, such as free energies of formation, from solubility data available in the literature together with standard properties of organic sulfur gases. However, a number of the properties for aqueous organic sulfur compounds have not been experimentally determined. Furthermore, most of thermodynamic data that are available are for 25 C and 1 bar. In order to determine reaction properties to temperatures and pressures appropriate to the hydrothermal conditions in which thermophilic organisms actually live, we use equations of state developed by Helgeson and co-workers (Helgeson et al., 1981, AJS 281, 1249). A key piece of information needed to go up in temperature is the partial molal heat capacity, which is one of the properties for which experimental data are unavailable for nearly all organic sulfur compounds. We have used correlation methods to determine the partial molal heat capacities and volumes of many organic solutes. These estimates allow us to asses the role of organic sulfur compounds during the reduction of carbon in hydrothermal settings. We will present these data, along with examples of the thermodynamic properties of reactions involving aqueous organic sulfur compounds.

Schulte, Mitchell; Rogers, Karyn L.; DeVincenzi, Donald L. (Technical Monitor)

2000-01-01

312

Process for removing an organic compound from water  

DOEpatents

A process for removing organic compounds from water is disclosed. The process involves gas stripping followed by membrane separation treatment of the stripping gas. The stripping step can be carried out using one or multiple gas strippers and using air or any other gas as stripping gas. The membrane separation step can be carried out using a single-stage membrane unit or a multistage unit. Apparatus for carrying out the process is also disclosed. The process is particularly suited for treatment of contaminated groundwater or industrial wastewater.

Baker, Richard W. (Palo Alto, CA); Kaschemekat, Jurgen (Palo Alto, CA); Wijmans, Johannes G. (Menlo Park, CA); Kamaruddin, Henky D. (San Francisco, CA)

1993-12-28

313

The synthesis of organic and inorganic compounds in evolved stars.  

PubMed

Recent isotopic analysis of meteorites and interplanetary dust has identified solid-state materials of pre-solar origin. We can now trace the origin of these inorganic grains to the circumstellar envelopes of evolved stars. Moreover, organic (aromatic and aliphatic) compounds have been detected in proto-planetary nebulae and planetary nebulae, which are the descendants of carbon stars. This implies that molecular synthesis is actively happening in the circumstellar environment on timescales as short as several hundred years. The detection of stellar grains in the Solar System suggests that they can survive their journey through the interstellar medium and that they are a major contributor of interstellar grains. PMID:15329712

Kwok, Sun

2004-08-26

314

Organic compounds in produced waters from shale gas wells.  

PubMed

A detailed analysis is reported of the organic composition of produced water samples from typical shale gas wells in the Marcellus (PA), Eagle Ford (TX), and Barnett (NM) formations. The quality of shale gas produced (and frac flowback) waters is a current environmental concern and disposal problem for producers. Re-use of produced water for hydraulic fracturing is being encouraged; however, knowledge of the organic impurities is important in determining the method of treatment. The metal content was determined by inductively coupled plasma optical emission spectrometry (ICP-OES). Mineral elements are expected depending on the reservoir geology and salts used in hydraulic fracturing; however, significant levels of other transition metals and heavier main group elements are observed. The presence of scaling elements (Ca and Ba) is related to the pH of the water rather than total dissolved solids (TDS). Using gas chromatography mass spectrometry (GC/MS) analysis of the chloroform extracts of the produced water samples, a plethora of organic compounds were identified. In each water sample, the majority of organics are saturated (aliphatic), and only a small fraction comes under aromatic, resin, and asphaltene categories. Unlike coalbed methane produced water it appears that shale oil/gas produced water does not contain significant quantities of polyaromatic hydrocarbons reducing the potential health hazard. Marcellus and Barnett produced waters contain predominantly C6-C16 hydrocarbons, while the Eagle Ford produced water shows the highest concentration in the C17-C30 range. The structures of the saturated hydrocarbons identified generally follows the trend of linear > branched > cyclic. Heterocyclic compounds are identified with the largest fraction being fatty alcohols, esters, and ethers. However, the presence of various fatty acid phthalate esters in the Barnett and Marcellus produced waters can be related to their use in drilling fluids and breaker additives rather than their presence in connate fluids. Halogen containing compounds are found in each of the water samples, and although the fluorocarbon compounds identified are used as tracers, the presence of chlorocarbons and organobromides formed as a consequence of using chlorine containing oxidants (to remove bacteria from source water), suggests that industry should concentrate on non-chemical treatments of frac and produced waters. PMID:25162586

Maguire-Boyle, Samuel J; Barron, Andrew R

2014-10-01

315

ORGANIC CATION EFFECTS ON THE SORPTION OF METALS AND NEUTRAL ORGANIC COMPOUNDS ON AQUIFER MATERIAL (JOURNAL VERSION)  

EPA Science Inventory

Sorption of ethylhexadecyldimethylammonium (EHDDMA+), a large organic cation, and three neutral organic compounds (NOC's) on two low organic carbon aquifer materials was studied using a soil batch equilibration technique. EHDDMA+ competed effectively with metals for exchange site...

316

Source apportionment of airborne particulate matter using organic compounds as tracers  

Microsoft Academic Search

A chemical mass balance receptor model based on organic compounds has been developed that relates sours; contributions to airborne fine particle mass concentrations. Source contributions to the concentrations of specific organic compounds are revealed as well. The model is applied to four air quality monitoring sites in southern California using atmospheric organic compound concentration data and source test data collected

Bernd R. T. Simoneit; WOLFGANG F. ROGGE; LYNN M. HILDEMANN; MONICA A. MAZUREK; GLEN R. CASS

1996-01-01

317

Biological degradation of some organic compounds involved in the paper industry  

Microsoft Academic Search

An evaluation of the biodegradation by aerobic microorganisms was investigated for some organic compounds occurring in paper manufacturing technology. Lines of biodegradation for nine organic compounds, as a percentage removal of chemical oxygen demand (COD), were detected over seven days incubation. The results of the biodegradability test clearly revealed that some of the organic compounds under investigation were highly biodegradable

Rifaat Abdel Wahaab

2002-01-01

318

40 CFR 60.502 - Standard for Volatile Organic Compound (VOC) emissions from bulk gasoline terminals.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Standard for Volatile Organic Compound (VOC) emissions from bulk gasoline...Terminals § 60.502 Standard for Volatile Organic Compound (VOC) emissions from bulk gasoline...collection system designed to collect the total organic compounds vapors displaced from tank...

2010-07-01

319

Cyclodextrin-based microsensors for volatile organic compounds  

SciTech Connect

Host-guest chemistry and self-assembly techniques are being explored to develop species selective thin-films for real-time sensing of volatile organic compounds (VOCs). Cyclodextrin (CD) and calixarene (CA) molecules are known to form guest-host inclusion complexes with a variety of organic molecules. Through the control of the cavity size and chemical functionality on the rims of these bucket-like molecules, the binding affinities for formation of inclusion complexes can be controlled and optimized for specific agents. Self-assembly techniques are used to covalently bond these reagent molecules to the surface of acoustic transducers to create dense, highly oriented, and stable thin films. Self-assembly techniques have also been used to fabricate multilayer thin film containing molecular recognition reagents through alternating adsorption of charged species in aqueous solutions. Self-assembly of polymeric molecules of the SAW device was also explored for fabricating species selective interfaces.

Swanson, B.; Johnson, S.; Shi, J.; Yang, Xiaoguang

1997-10-01

320

Volatilization modeling of semivolatile organic compounds during solidification processes  

SciTech Connect

Technical information is provided on the effects of temperature elevation on increasing the volatility of semivolatile organic compounds (SVOCs) in stabilization media. A chemical diffusion model was developed (1) to establish a technical basis for determining maximum treatment temperatures above which SVOCs should not be exposed during solidification processes to reduce the potential for unacceptable releases; and (2) to prescribe types of binders with sufficiently low heat output to stabilize organics that have potential for volatilizing with moderate heating, and to recommend against use of others that may not maintain the mixture at sufficiently low temperatures. A non-steady-state model for linear diffusion in the aqueous and vapor phase was used because the SVOC dynamics of diffusion are controlled by resistances in both pore water and air. The results of volatilization calculations performed are presented.

Sass, B.M.; Smith, L.A. Huang, W.M.C.; Rosansky, S.H.; Drescher, E. [Battelle Memorial Inst. (BMI), Columbus, OH (United States). Environmental Technology Dept.

1996-12-31

321

Laboratory Studies of Organic Compounds With Reflectance Spectroscopy  

NASA Astrophysics Data System (ADS)

In order to properly interpret reflectance spectra of any solar system surface from the earth to the Oort cloud, laboratory spectra of candidate materials for comparative analysis are needed. Although the common cosmochemical species (H2O, CO2, CO, NH3, and CH4) are well represented in the spectroscopic literature, comparatively little reflectance work has been done on organics from room to cryogenic temperatures at visible to near infrared wavelengths. Reflectance spectra not only enhance weak or unseen transmission features, they are also more analogous to spectra obtained by spacecraft that are imaging such bodies as giant planet moons, kuiper belt objects, centaurs, comets and asteroids, as well as remote sensing of the earth. The USGS Spectroscopy Laboratory is measuring reflectance spectra of organic compounds from room to cryogenic temperatures over the spectral range of 0.35 to 15.5 microns. This region encompasses the fundamental absorptions and many overtones and combinations of C, H, O, and N molecular bonds. Because most organic compounds belong to families whose members have similar structure and composition, individual species identification within a narrow wavelength range may be ambiguous. By measuring spectral reflectance of the pure laboratory samples from the visible through the near and mid-infrared, absorption bands unique to each can be observed, cataloged, and compared to planetary reflectance data. We present here spectra of organic compounds belonging to five families: the alkanes, alkenes, alkynes, aromatics, and cyanides. Common to all of these are the deep C-H stretch fundamental absorptions, which shift shortward from 3.35+ microns in alkanes to 3.25+ microns in aromatics, to 3.2+ microns in alkenes, and down to 3.0+ microns in alkynes. Mid-IR absorptions due to C-H bending deformations at 6.8+ and 7.2+ microns are also identified. In the near infrared these stretching and bending fundamentals yield a diagnostic set of combination absorptions at approximately 2.3 microns, as well as the first C-H stretching overtones at 1.6 to 1.7 microns, and even the second stretching overtones at 1.2+ microns. Additionally, the spectral properties of these organic materials have applications to remote sensing of terrestrial environments, including hazardous waste and disaster site characterization.

Curchin, J. M.; Clark, R. N.; Hoefen, T. M.

2007-12-01

322

Pesticides and the Third World.  

PubMed

Many developing countries are importing industrial processes that make use of toxic chemicals. By the same token, pesticides, which are toxic by design, are also used increasingly in agriculture and in public health programs to control pests and vector-borne diseases. Recent estimates suggest that pesticides account for more than 20,000 fatalities yearly, and that most of these will have occurred in developing countries. This may actually be a gross underreporting. Although organophosphate and carbamate insecticides are still responsible for many of those poisoning cases, herbicides such as paraquat are also increasingly being implicated in fatal poisoning cases. Newer pesticides such as the synthetic derivatives of pyrethrin, which were believed to be relatively safe to humans, now appear to be implicated in some serious cases of intoxication. Community-based pest control using locally available botanical pesticides could have severe consequences unless the toxicity of these compounds is carefully assessed relative to nontarget organisms. A high proportion of pesticide intoxications appear to be due to lack of knowledge, unsafe attitudes, and dangerous practices. The technology available to small farmers for pesticide application is often inappropriate: faulty sprayers, lack of protective equipment adapted to tropical conditions, nonexistent first-aid provisions. Agricultural extension is often not oriented to the transfer of information relative to the dangers inherent in the use of pesticides. The lack of information at all levels may be one of the most important causative factors of chemical intoxication in developing countries. Research should at this time concentrate on behaviors leading to chemical intoxication. This should be done concurrently with proper prospective and retrospective surveys of poisonings in developing country communities. More information should be sought relative to the decision processes of import, legislation, and licensing. Research and development efforts in appropriate technology and safety devices are also critically needed. PMID:1987360

Forget, G

1991-01-01

323

Emissions and Secondary Organic Aerosol Production from Semivolatile and Intermediate Volatility Organic Compounds  

NASA Astrophysics Data System (ADS)

Organic aerosols are a highly-dynamic system dominated by both variable gas-particle partitioning and chemical evolution. Important classes of organics include semivolatile and intermediate volatility organic compounds (SVOC and IVOC, respectively). SVOCs are compounds that exist in both the gas and particle phases at typical atmospheric conditions while IVOC are low-volatility vapors that exist exclusively in the gas phase. Both classes have saturation concentrations that are orders of magnitude lower than volatile organic compounds (VOC) that are the traditional subjects of atmosphere chemistry, such as monoterpenes, alkyl benzenes, etc. The SVOC and IVOC are poorly represented for in current atmospheric chemistry models. Source testing indicates that SVOC and IVOC emissions from biomass combustion, diesel engines and other sources exceed the primary organic aerosol emissions; thus the oxidation of these vapors could serve as a significant source of organic aerosol in the atmosphere. The formation of secondary organic aerosol (SOA) from the reactions between OH radicals and SVOCs and IVOCs was investigated in the Carnegie Mellon University smog chamber. Experiments were conducted with n-alkanes and emission surrogates (diesel fuel and lubricating oil). SVOC oxidation produces oxidized organic aerosol but little new organic aerosol mass. This behavior can be explained by the coupled effects of partitioning and aging. Oxidation of SVOC vapors creates low volatility species that partition into the condensed phase; this oxidation also reduces the SVOC vapor concentration which, in turn, requires particle-phase SVOC to evaporate to maintain phase equilibrium. In contrast, oxidation of IVOC results in sustained production of SOA consistent with a reaction with relatively slow kinetics and high mass yield. Aerosol Mass Spectrometer data indicates that the SOA formed from IVOC has a mass spectrum that is quite similar to the oxygenated organic aerosol factor observed in field studies.

Robinson, A. L.; Presto, A. A.; Miracolo, M. A.; Donahue, N. M.; Kroll, J. H.; Worsnop, D. R.

2008-12-01

324

Impact of Pesticides as Organic Micro-Pollutants on the Environment and Risks for Mankind  

Microsoft Academic Search

\\u000a Because of health concerns, persistence, and long-term environmental effects, the impact of pesticides on agriculture and\\u000a public health has been the subject of considerable research. Organophosphorus pesticides exert their acute effects by inhibiting\\u000a acetylcholinesterase in the nervous system with subsequent accumulation of toxic levels of acetylcholine. Herbicides have\\u000a widely variable toxicity. In addition to acute toxicity from high exposures, there

Faruk Bozoglu

325

Pesticides and inner-city children: exposures, risks, and prevention.  

PubMed Central

Six million children live in poverty in America's inner cities. These children are at high risk of exposure to pesticides that are used extensively in urban schools, homes, and day-care centers for control of roaches, rats, and other vermin. The organophosphate insecticide chlorpyrifos and certain pyrethroids are the registered pesticides most heavily applied in cities. Illegal street pesticides are also in use, including tres pasitos (a carbamate), tiza china, and methyl parathion. In New York State in 1997, the heaviest use of pesticides in all counties statewide was in the urban boroughs of Manhattan and Brooklyn. Children are highly vulnerable to pesticides. Because of their play close to the ground, their hand-to-mouth behavior, and their unique dietary patterns, children absorb more pesticides from their environment than adults. The long persistence of semivolatile pesticides such as chlorpyrifos on rugs, furniture, stuffed toys, and other absorbent surfaces within closed apartments further enhances urban children's exposures. Compounding these risks of heavy exposures are children's decreased ability to detoxify and excrete pesticides and the rapid growth, development, and differentiation of their vital organ systems. These developmental immaturities create early windows of great vulnerability. Recent experimental data suggest, for example, that chlorpyrifos may be a developmental neurotoxicant and that exposure in utero may cause biochemical and functional aberrations in fetal neurons as well as deficits in the number of neurons. Certain pyrethroids exert hormonal activity that may alter early neurologic and reproductive development. Assays currently used for assessment of the toxicity of pesticides are insensitive and cannot accurately predict effects to children exposed in utero or in early postnatal life. Protection of American children, and particularly of inner-city children, against the developmental hazards of pesticides requires a comprehensive strategy that monitors patterns of pesticide use on a continuing basis, assesses children's actual exposures to pesticides, uses state-of-the-art developmental toxicity testing, and establishes societal targets for reduction of pesticide use. Images Figure 1 Figure 2 PMID:10346991

Landrigan, P J; Claudio, L; Markowitz, S B; Berkowitz, G S; Brenner, B L; Romero, H; Wetmur, J G; Matte, T D; Gore, A C; Godbold, J H; Wolff, M S

1999-01-01

326

Life cycle toxicity assessment of pesticides used in integrated and organic production of oranges in the Comunidad Valenciana, Spain.  

PubMed

The relative impacts of 25 pesticides including acaricides, fungicides, herbicides, insecticides, and post-harvest fungicides, used in the production of oranges in Spain were assessed with current life cycle impact assessment (LCIA) tools. Chemical specific concentrations were combined with pesticide emission data and information on chemical toxicity to assess human toxicity and freshwater ecotoxicity impacts. As a case study, the relative impacts of two orange production systems in the region of Valencia, integrated pest management (IP) and organic production (OP), were assessed. The evaluation of active ingredients showed that on average acaricides have the highest human toxicity impact scores, while for freshwater ecotoxicity insecticides show the highest impact. In both impact categories the lowest impact scores were calculated for herbicides. In the production of 1 kg of orange fruits, where several kinds of pesticides are combined, results show that post-harvest fungicides can contribute more than 95% to the aggregate human toxicity impacts. More than 85% of aquatic ecotoxicity is generated by fungicides applied before harvest. The potential to reduce impacts on freshwater ecosystems is seven orders of magnitude, while impacts on human health can be reduced by two orders of magnitude. Hence, this stresses the importance of a careful pre-selection of active ingredients. In both impact categories, organic production represents the least toxic pest-control method. PMID:21075421

Juraske, Ronnie; Sanjuán, Neus

2011-02-01

327

Biofiltration for control of volatile organic compounds (VOCS)  

SciTech Connect

Air biofiltration is a promising technology for control of air emissions of biodegradable volatile organic compounds (VOCs). In conjunction with vacuum extraction of soils or air stripping of ground water, it can be used to mineralize VOCs removed from contaminated soil or groundwater. The literature describes three major biological systems for treating contaminated air bioscrubbers, biotrickling filters and biofilters. Filter media can be classified as: bioactive fine or irregular particulates, such as soil, peat, compost or mixtures of these materials; pelletized, which are randomly packed in a bed; and structured, such as monoliths with defined or variable passage size and geometry. The media can be made of sorbing and non-absorbing materials. Non-bioactive pelletized and structured media require recycled solutions of nutrients and buffer for efficient microbial activity and are thus called biotrickling filters. Extensive work has been conducted to improve biofiltration by EPA`s Risk Reduction Engineering Laboratory and the University of Cincinnati in biofilters using pelletized and structured media and improved operational approaches. Representative VOCs in these studies included compounds with a range of aqueous solubilities and octanol-water partition coefficients. The compounds include iso-pentane, toluene, methylene chloride, trichloroethylene (TCE), ethyl benzene, chlorobenzene and perchloroethylene (PCE) and alpha ({alpha}-) pinene. Comparative studies were conducted with peat/compost biofilters using isopentane and {alpha}-pinene. Control studies were also conducted to investigate adsorption/desorption of contaminants on various media using mercuric chloride solution to insure the absence of bioactivity.

Bishop, D.F. [Environmental Protection Agency, Cincinnati, OH (United States); Govind, R. [Univ. of Cincinnati, OH (United States)

1995-10-01

328

EVALUATION OF MOBILITY OF PESTICIDES IN SOIL USING U.S. EPA (ENVIRONMENTAL PROTECTION AGENCY) METHODOLOGY (JOURNAL VERSION)  

EPA Science Inventory

A methodology developed by the U.S. Environmental Protection Agency for evaluating the mass transport potential of hazardous organic compounds through environmental pathways is used to determine the potential mobility of eight chlorinated and organophosphorus pesticides in soil s...

329

Biogenic volatile organic compound emissions from vegetation fires  

PubMed Central

The aim of this paper was to provide an overview of the current state of the art on research into the emission of biogenic volatile organic compounds (BVOCs) from vegetation fires. Significant amounts of VOCs are emitted from vegetation fires, including several reactive compounds, the majority belonging to the isoprenoid family, which rapidly disappear in the plume to yield pollutants such as secondary organic aerosol and ozone. This makes determination of fire-induced BVOC emission difficult, particularly in areas where the ratio between VOCs and anthropogenic NOx is favourable to the production of ozone, such as Mediterranean areas and highly anthropic temperate (and fire-prone) regions of the Earth. Fire emissions affecting relatively pristine areas, such as the Amazon and the African savannah, are representative of emissions of undisturbed plant communities. We also examined expected BVOC emissions at different stages of fire development and combustion, from drying to flaming, and from heatwaves coming into contact with unburned vegetation at the edge of fires. We conclude that forest fires may dramatically change emission factors and the profile of emitted BVOCs, thereby influencing the chemistry and physics of the atmosphere, the physiology of plants and the evolution of plant communities within the ecosystem. PMID:24689733

CICCIOLI, PAOLO; CENTRITTO, MAURO; LORETO, FRANCESCO

2014-01-01

330

Determination of selenium and its compounds in marine organisms.  

PubMed

In this study, we investigate the type and quantity of selenium compounds in fish and marine organisms, using ion-pair reversed phase LC–ICP-MS, developed and applied for the analysis of Atlantic cod, Atlantic salmon, Greenland halibut, Atlantic herring, blue mussel, common crab, scallop, calanus, and Euphasia super. Of the samples examined, the lowest level of selenium was found in farmed Atlantic salmon (0.17 mg Se kg(?1) dm). The total selenium extraction efficiency by phosphate buffer was 2.5 times higher in sea plankton and shellfish samples than in fish samples. Analysis of Se species in each hydrolysate obtained by proteolysis showed the presence of selenomethionine, which constituted 41.5% of the selenium compounds detected in hydrolysates of Atlantic herring and 98.4% of those in extracts of Atlantic salmon. Inorganic compounds, such as selenates and selenites, were detected mainly in sea plankton and shellfish samples (<0.13 mg Se kg(?1) wm), although no correlation was found between the presence of inorganic compounds and total selenium concentration. The accuracy of the total selenium determination was validated using a certified reference material (oyster tissue (NIST 1566b)). A lyophilised powder of cod (Gadus morhua) was used to validate speciation analysis, enzymatic hydrolysis of lyophilised powder of cod recovered 54 ± 6% of total selenium, and SeMet constituted 83.5 ± 5.28% of selenium detected in hydrolysates. The chromatographic detection limits were, respectively, 0.30 ng mL(?1), 0.43 ng mL(?1), 0.54 ng mL(?1), 0.55 ng mL(?1), 0.57 ng mL(?1) and 0.72 ng mL(?1) for selenate, selenomethionine, selenite, Se-methyl-selenocysteine, selenocystine and selenomethionine selenoxide.The data on selenium concentrations and speciation presented here could be useful in estimating levels of selenium intake by seafood consumption. PMID:25468190

Bryszewska, Ma?gorzata Anita; Måge, Amund

2015-01-01

331

40 CFR Table 1 to Subpart B of... - Volatile Organic Compound (VOC) Content Limits for Automobile Refinish Coatings  

Code of Federal Regulations, 2010 CFR

...Organic Compound (VOC) Content Limits for Automobile Refinish Coatings 1 Table 1 to Subpart...Organic Compound Emission Standards for Automobile Refinish Coatings Pt. 59, Subpt...Organic Compound (VOC) Content Limits for Automobile Refinish Coatings Coating...

2010-07-01

332

Man-Made Organic Compounds in Source Water of Nine Community Water Systems that Withdraw from Streams, 2002-05  

USGS Publications Warehouse

Initial findings from a national study by the National Water-Quality Assessment (NAWQA) Program of the U.S. Geological Survey (USGS) characterize the occurrence of about 250 anthropogenic organic compounds in source water (defined as water collected at a surface-water intake prior to water treatment) at nine community water systems in nine States in the Nation. The organic compounds analyzed in this study are primarily man-made and include pesticides, solvents, gasoline hydrocarbons, personal-care and domestic-use products, disinfection by-products, and manufacturing additives. The study also describes and compares the occurrence of selected compounds detected in source water with their occurrence in finished water, which is defined as water that has passed through treatment processes but prior to distribution. This fact sheet summarizes major findings and implications of the study and serves as a companion product to two USGS reports that present more detailed and technical information for the nine systems studied during 2002-05 (Carter and others, 2007; Kingsbury and others, 2008).

Kingsbury, James A.; Delzer, Gregory C.; Hamilton, Pixie A.

2008-01-01

333

Removal of gasoline volatile organic compounds via air biofiltration  

SciTech Connect

Volatile organic compounds (VOCs) generated by vapor extraction and air-stripping systems can be biologically treated in an air biofiltration unit. An air biofilter consists of one or more beds of packing material inoculated with heterotrophic microorganisms capable of degrading the organic contaminant of concern. Waste gases and oxygen are passed through the inoculated packing material, where the microorganisms will degrade the contaminant and release CO{sub 2} + H{sub 2}O. Based on data obtained from a treatability study, a full-scale unit was designed and constructed to be used for treating gasoline vapors generated by a vapor-extraction and groundwater-treatment system at a site in California. The unit is composed of two cylindrical reactors with a total packing volume of 3 m{sup 3}. Both reactors are packed with sphagnum moss and inoculated with hydrocarbon-degrading microorganisms of Pseudomonas and Arthrobacter spp. The two reactors are connected in series for air-flow passage. Parallel lines are used for injection of water, nutrients, and buffer to each reactor. Data collected during the startup program have demonstrated an air biofiltration unit with high organic-vapor-removal efficiency.

Miller, R.S.; Saberiyan, A.G.; Esler, C.T. [AGRA Earth and Environmental, Inc., Portland, OR (United States); DeSantis, P. [BP Oil Co., Renton, WA (United States); Andrilenas, J.S. [AGRA Earth and Environmental, Inc., Phoenix, AZ (United States)

1995-12-31

334

Occurrence of Pharmaceutical and Other Organic Compounds in Ground Water in Ten Regions of California, USA  

NASA Astrophysics Data System (ADS)

A State-wide assessment of the occurrence of pharmaceuticals, pesticides, and other anthropogenic and natural constituents in ground-water aquifers that are used for public supply is being made as part of the California Ground-Water Assessment and Monitoring Program (http:ca.water.usgs.gov/gama/). During the first three years of the program, a total of 682 wells were sampled in ten areas of California representing a wide range of climatic, land-use, population density, and hydrogeologic conditions. Although the wells were generally deep (greater than 100 meters below land surface), the percent of wells containing at least one pesticide ranged from 15 to 88 in the ten study areas. In contrast, the detection frequency of pharmaceuticals ranged from 5 to 22 percent. Concentrations of pharmaceutical compounds were generally less than 50 parts per trillion. Of the 14 pharmaceutical compounds investigated, only 3 were detected in more than half of the study areas (carbamazapine, acetaminophen, and sulfmethoxazole) and only one was detected in more than 2 percent of the wells (carbamapazine). These 3 compounds have low soil-water partition coefficients (Kd) and are presumably less degradable, with respect to the time of transport to the sampled portion of the aquifer, compared to the other compounds. These 3 compounds are also a subset of the pharmaceuticals that have been detected most frequently in surface water. Several other pharmaceutical compounds that are frequently detected in surface water but not abundant in this study have high Kd values, suggesting sorption onto aquifer solids may limit their sub- surface transport, or have faster degradation rates. The occurrence of pharmaceutical compounds is not well correlated with that of pesticides, but may be related to land-use as the highest detection frequency occurred in the study unit with the highest urban density.

Domagalski, J.; Belitz, K.; Furlong, E. T.

2007-05-01

335

Distribution and trend of organochlorine pesticides in Galicia coast using mussels as bioindicator organisms. Possible relationship to biological parameters.  

PubMed

Contamination of organochlorine pesticides (OCPs) such as DDT and its metabolites (?DDs), ?-HCH (hexachlorocyclohexane), HCB (hexachlorobenzene), aldrin, endrin, isodrin and trans-nonachlor were investigated in wild mussels (Mytilus galloprovincialis) collected from Galician Rías (Rías of Ferrol, A Coruña, Muros, Arousa, Pontevedra and Vigo) during the period 1998-2012. Biological parameters, lipid content, shell length and condition index, were also studied. The OCPs levels in the wild mussel were in the order ?DDs>?-HCH>HCB. The other pesticides, aldrin, endrin, isodrin and trans-nonachlor, were not detected or were below the analytical detection limit. All concentrations found in these samples were below the allowable limits for human consumption (Regulation (EC) no. 396/2005). Univariate analysis confirmed that levels of some compounds presented significant relation with biological parameters. Multivariate analysis of the OCPs levels revealed significantly differences between studied Rías, samples from Ría of Ferrol had the highest levels of these compounds (values of ?DDs ranged from 3.9 to 4.2 ng g(-1) ww) and samples from Ría of Arousa, the lowest levels (values of ?DDs from 1.3 to 2.4 ng g(-1) ww). Temporal trends showed a decrease of OCPs levels along the studied period 1998-2012 in the Galician Rías. PMID:24374186

Carro, N; Cobas, J; García, I; Ignacio, M; Mouteira, A

2014-05-01

336

Degradation of chlorotriazine pesticides by sulfate radicals and influence of organic matter.  

PubMed

Atrazine, propazine, and terbuthylazine are chlorotriazine herbicides that have been frequently used in agriculture and thus are potential drinking water contaminants. Hydroxyl radicals produced by advanced oxidation processes can degrade these persistent compounds. These herbicides are also very reactive with sulfate radicals (2.2-4.3 × 109 M-1 s-1). However, the dealkylated products of chlorotriazine pesticides are less reactive towards sulfate radicals (e.g., desethyl-desisopropyl-atrazine (DEDIA; 1.5 × 108 M-1 s -1). The high reactivity of the herbicides is largely due to the ethyl- or isopropyl group. For example, desisopropyl-atrazine (DIA) reacts quickly (k = 2 × 109 M-1 s-1), whereas desethyl-atrazine (DEA) reacts more slowly (k = 9.6 × 108 M-1 s-1). The tert-butyl group does not have a strong effect on reaction rate, as shown by the similar second order reaction rates between desethyl-terbuthylazine (DET; k = 3.6 × 108 M-1 s-1) and DEDIA. Sulfate radicals degrade a significant proportion of atrazine (63%) via dealkylation, in which deethylation significantly dominates over deisopropylation (10:1). Sulfate- and hydroxyl radicals react at an equally fast rate with atrazine (k (hydroxyl radical + atrazine) = 3 × 109 M-1 s-1). However, sulfate- and hydroxyl radicals differ considerably in their reaction rates with humic acids (k (sulfate radical + humic acids) = 6.6 × 103 L mg C-1 s-1; k (hydroxyl radical + humic acids) = 1.4 × 104 L mg C-1 s-1). Thus, in the presence of humic acids, atrazine is degraded more efficiently by sulfate radicals than by hydroxyl radicals. PMID:25347797

Lutze, Holger V; Bircher, Stephanie; Rapp, Insa; Kerlin, Nils; Bakkour, Rani; Geisler, Melanie; von Sonntag, Clemens; Schmidt, Torsten C

2014-10-27

337

Effect of water saturation in soil organic matter on the partition of organic compounds  

USGS Publications Warehouse

The sorption of benzene, trichloroethylene, and carbon tetrachloride at room temperature from water solution and from vapor on two high-organic-content soils (peat and muck) was determined in order to evaluate the effect of water saturation on the solute partition in soil organic matter (SOM). The uptake of water vapor was similarly determined to define the amounts of water in the saturated soil samples. In such high-organic-content soils the organic vapor sorption and the respective solute sorption from water exhibit linear isotherms over a wide range of relative concentrations. This observation, along with the low BET surface areas of the samples, suggests that partition in the SOM of the samples is the dominant process in the uptake of these liquids. A comparison of the sorption from water solution and from vapor phase shows that water saturation reduces the sorption (partition) efficiency of SOM by ?? 42%; the saturated water content is ??38% by weight of dry SOM. This reduction is relatively small when compared with the almost complete suppression by water of organic compound adsorption on soil minerals. While the effect of water saturation on solute uptake by SOM is much expected in terms of solute partition in SOM, the influence of water on the solubility behavior of polar SOM can be explained only qualitatively by regular solution theory. The results suggest that the major effect of water in a drying-wetting cycle on the organic compound uptake by normal low-organic-content soils (and the associated compound's activity) is the suppression of adsorption by minerals rather than the mitigation of the partition effect in SOM.

Rutherford, D.W.; Chlou, G.T.

1992-01-01

338

Source apportionment of ambient volatile organic compounds in Beijing.  

PubMed

The ambient air quality standard for ozone is frequently exceeded in Beijing in summer and autumn. Source apportionments of volatile organic compounds (VOCs), which are precursors of ground-level ozone formation, can be helpful to the further study of tropospheric ozone formation. In this study, ambient concentrations of VOCs were continuously measured with a time resolution of 30 min in August 2005 in Beijing. By using positive matrix factorization (PMF), eight sources for the selected VOC species were extracted. Gasoline-related emissions (the combination of gasoline exhaust and gas vapor), petrochemicals, and liquefied petroleum gas (LPG) contributed 52, 20, and 11%, respectively, to total ambient VOCs. VOC emissions from natural gas (5%), painting (5%), diesel vehicles (3%), and biogenic emissions (2%) were also identified. The gasoline-related, petrochemical, and biogenic sources were estimated to be the major contributors to ozone formation potentials in Beijing. PMID:17626435

Song, Yu; Shao, Min; Liu, Ying; Lu, Sihua; Kuster, William; Goldan, Paul; Xie, Shaodong

2007-06-15

339

Indoor volatile organic compounds and chemical sensitivity reactions.  

PubMed

Studies of unexplained symptoms observed in chemically sensitive subjects have increased the awareness of the relationship between neurological and immunological diseases due to exposure to volatile organic compounds (VOCs). However, there is no direct evidence that links exposure to low doses of VOCs and neurological and immunological dysfunction. We review animal model data to clarify the role of VOCs in neuroimmune interactions and discuss our recent studies that show a relationship between chronic exposure of C3H mice to low levels of formaldehyde and the induction of neural and immune dysfunction. We also consider the possible mechanisms by which VOC exposure can induce the symptoms presenting in patients with a multiple chemical sensitivity. PMID:24228055

Win-Shwe, Tin-Tin; Fujimaki, Hidekazu; Arashidani, Keiichi; Kunugita, Naoki

2013-01-01

340

Detection of volatile organic compounds using surface enhanced Raman scattering  

SciTech Connect

The authors present the detection of volatile organic compounds directly in their vapor phase by surface-enhanced Raman scattering (SERS) substrates based on lithographically-defined two-dimensional rectangular array of nanopillars. The type of nanopillars is known as the tapered pillars. For the tapered pillars, SERS enhancement arises from the nanofocusing effect due to the sharp tip on top. SERS experiments were carried out on these substrates using various concentrations of toluene vapor. The results show that SERS signal from a toluene vapor concentration of ppm level can be achieved, and the toluene vapor can be detected within minutes of exposing the SERS substrate to the vapor. A simple adsorption model is developed which gives results matching the experimental data. The results also show promising potential for the use of these substrates in environmental monitoring of gases and vapors.

Chang, A S; Maiti, A; Ileri, N; Bora, M; Larson, C C; Britten, J A; Bond, T C

2012-03-22

341

Microscale solvent extraction methods for organic compound analyses  

SciTech Connect

The use of microscale solvent extraction (MSE) methods has several advantages over conventional methods. For example, MSE methods use much less solvent and generate much less waste. Because of the small scale equipment and glassware and the decreased solvent, MSE methods are more easily adaptable for on-site use, and can result in reduced costs for field sampling and analysis programs. Several MSE methods have been evaluated by META Environmental, Inc. (META) for the Electric Power Research Institute (EPRI) for the determination of selected organic compounds in various matrices. One method was developed for the simultaneous determination of monocyclic aromatic hydrocarbons (MAHs) and polycyclic aromatic hydrocarbons (PAHs) in soil. Tests of precision, recovery, and comparability to standard methods have been completed, and the results compare favorably with standard methods. The method has been applied successfully to environmental studies of sites containing wood preservative chemicals, former manufactured gas plant (MGP) wastes, and other MAH/PAH-containing contaminants.

Mauro, D.M.; Young, M.S.; Taylor, B.B. [META Environmental, Inc., Watertown, MA (United States); Murarka, I.P. [Electric Power Research Inst., Palo Alto, CA (United States)

1994-12-31

342

Flux Measurements of Volatile Organic Compounds from an Urban Landscape  

SciTech Connect

Direct measurements of volatile organic compound (VOC) emissions that include all anthropogenic and biogenic emission sources in urban areas are a missing requirement to evaluate emission inventories and constrain current photochemical modelling practices. Here we demonstrate the use of micrometeorological techniques coupled with fast-response sensors to measure urban VOC fluxes from a neighborhood of Mexico City, where the spatial variability of surface cover and roughness is high. Fluxes of olefins, methanol, acetone, toluene and C2-benzenes were measured and compared with the local gridded emission inventory. VOC fluxes exhibited a clear diurnal pattern with a strong relationship to vehicular traffic. Recent photochemical modeling results suggest that VOC emissions are significantly underestimated in Mexico City1, but the measured VOC fluxes described here indicate that the official emission inventory2 is essentially correct. Thus, other explanations are needed to explain the photochemical modelling results.

Velasco, E.; Lamb, Brian K.; Pressley, S.; Allwine, Eugene J.; Westberg, Halvor; Jobson, B Tom T.; Alexander, M. Lizabeth; Prazeller, Peter; Molina, Luisa; Molina, Mario J.

2005-10-19

343

Source apportionment of volatile organic compounds in Tehran, Iran.  

PubMed

Identifying the sources of volatile organic compounds (VOCs) is key issue to reducing ground-level ozone and PAN. A multivariate receptor model (Unmix) was used for the determination of the contributions of VOCs sources in Tehran-Iran. Concentrations of ambient C2-C10 VOCs were measured continuously and online at the center of Tehran city during the winter of 2012. A high correlation coefficient existed between measured and predicted values (R (2) = 0.99), indicating that the data were well modeled. Five possible VOCs source categories were identified and mobile sources such as vehicle exhaust (61 %) and fuel evaporation (12 %) more than half of the total VOC concentration. City gas and CNG sources, biogenic source, and industrial solvent source categories accounted for 17 %, 8 % and 2 % of the total VOC, respectively. Result showed Unmix for VOCs source apportionment can be used to analyze and generate air pollution control strategies and policies. PMID:23283536

Sarkhosh, Maryam; Mahvi, Amir Hossein; Yunesian, Masud; Nabizadeh, Ramin; Borji, Saeedeh Hemmati; Bajgirani, Ali Ghiami

2013-04-01

344

Exposure to volatile organic compounds: Comparison among different transportation modes  

NASA Astrophysics Data System (ADS)

The increasing trend of promoting public transportation (bus tram, metro, train) and more environmental friendly and sustainable non fossil-fuel alternatives (walking, cycling etc) as substitutes for auto vehicles brings forward new questions with regard to pollutant levels to which commuters are exposed. In this study, three transportation modes (tram, auto vehicle and bicycle) are studied and concentration levels of 84 volatile organic compounds (VOCs) (hydrocarbons, aromatic hydrocarbons, oxygen containing hydrocarbons, terpenes and halogenated compounds) are measured along a route in the city of Ghent, Belgium. The concentration levels are obtained by active sampling on Tenax TA sorbent tubes followed by thermal desorption gas chromatography mass spectrometry (TD-GC-MS) using deuterated toluene as an internal standard. The median total VOC concentrations for the tram mode (33 ?g/m³) is 1.7 times higher than that of the bicycle mode (20 ?g/m³) and 1.5 times higher than for the car mode (22 ?g/m³). It is found that aromatic hydrocarbons account for a significant proportion in the total VOCs concentration (TVOCs) being as high as 41-57%, 59-72% and 58-72% for the tram, car and bicycle respectively. In all transportation modes, there was a high (r > 0.6) degree of correlation between BTEX compounds, isopropylbenzene, n-propylbenzene, 1,3,5-trimethylbenzene and 1,2,4-trimethylbenzene. When comparing time weighed average concentrations along a fixed route in Ghent, it is found that commuters using the tram mode experience the highest TVOCs concentration levels. However, next to the concentration level to which commuters are exposed, the physical activity level involving the mode of transportation is important to assess the exposure to toxic VOCs. It is proven that the commuter using a bicycle (4.3 ± 1.5 ?g) inhales seven and nine times more benzene compared to the commuter using the car and tram respectively, when the same route is followed.

Do, Duc Hoai; Van Langenhove, Herman; Chigbo, Stephen Izuchukwu; Amare, Abebech Nuguse; Demeestere, Kristof; Walgraeve, Christophe

2014-09-01

345

Constituents of volatile organic compounds of evaporating essential oil  

NASA Astrophysics Data System (ADS)

Essential oils containing aromatic compounds can affect air quality when used indoors. Five typical and popular essential oils—rose, lemon, rosemary, tea tree and lavender—were investigated in terms of composition, thermal characteristics, volatile organic compound (VOC) constituents, and emission factors. The activation energy was 6.3-8.6 kcal mol -1, the reaction order was in the range of 0.6-0.8, and the frequency factor was 0.01-0.24 min -1. Toluene, 1,2,3-trimethylbenzene, 1,2,4-trimethylbenzene, n-undecane, p-diethylbenzene and m-diethylbenzene were the predominant VOCs of evaporating gas of essential oils at 40 °C. In addition, n-undecane, p-diethylbenzene, 1,2,4-trimethylbenzene, m-diethylbenzene, and 1,2,3-trimethylbenzene revealed high emission factors during the thermogravimetric (TG) analysis procedures. The sequence of the emission factors of 52 VOCs (137-173 mg g -1) was rose ? rosemary > tea tree ? lemon ? lavender. The VOC group fraction of the emission factor of aromatics was 62-78%, paraffins were 21-37% and olefins were less than 1.5% during the TG process. Some unhealthy VOCs such as benzene and toluene were measured at low temperature; they reveal the potential effect on indoor air quality and human health.

Chiu, Hua-Hsien; Chiang, Hsiu-Mei; Lo, Cho-Ching; Chen, Ching-Yen; Chiang, Hung-Lung

2009-12-01

346

Membrane bioreactor for control of volatile organic compound emissions  

SciTech Connect

A membrane bioreactor system that overcomes many of the limitations of conventional compost biofilters is described. The system utilizes microporous hydrophobic hollow fiber membranes for mass transfer of volatile organic compounds (VOCs) from the gas phase to a microbially active liquid phase. The reactor design provides a high biomass concentration, a method for wasting biomass, and a method for addition of pH buffers, nutrients, cometabolites, and/or other amendments. A theoretical model is developed, describing mass transfer and biodegradation in the membrane bioreactor. Reactor performance was determined in a laboratory scale membrane bioreactor over a range of gas loading rates using toluene as a model VOC. Toluene removal efficiency was greater than 98% at an inlet concentration of 100 ppm, and a gas residence time of less than 2 s. Factors controlling bioreactor performance were determined through both experiments and theoretical modeling to include: compound Henry`s law constant, membrane specific surface area, gas and VOC loading rates, liquid phase turbulence, and biomass substrate utilization rate.

Ergas, S.J. [Univ. of Massachusetts, Amherst, MA (United States). Dept. of Civil and Environmental Engineering; McGrath, M.S. [Monsanto Enviro-Chem Systems Inc., Chesterfield, MO (United States)

1997-06-01

347

Pesticide analysis by MEKC on a microchip with hydrodynamic injection from organic extract.  

PubMed

An integrated microchip for monitoring carbamate pesticides in environmental water using continuous flow chemical processes is under development, i. e., the integration of hydrolysis, azo-derivatization, liquid-liquid extraction, electrophoretic separation, and quantification. The separation of the derivatives of four carbamate pesticides (carbaryl, carbofuran, propoxur, and bendiocarb) extracted in the continuous flow of a 1-butanol phase was studied in a silica microchip using micellar EKC. A baseline separation of four pesticide derivatives was achieved on a silica chip using hydrodynamic injection with electroosmotic gating. Detection using a thermal lens microscope showed good linearity in the concentration range of 10(-6 )-10(-5 )M with an LOD of 5 x 10(-7) M, which is superior to that of conventional CE with UV absorption detection at a level of 10(-4) M. PMID:18300211

Smirnova, Adelina; Shimura, Kiyohito; Hibara, Akihide; Proskurnin, Mikhail A; Kitamori, Takehiko

2008-03-01

348

A SURVEY ON RESEARCH NEEDS ON PERSONAL SAMPLERS FOR TOXIC ORGANIC COMPOUNDS  

EPA Science Inventory

A survey is presented on the research and development needs for personal monitoring devices for toxic organic compounds in the ambient atmosphere. This survey includes a description of organic compounds and their ambient concentrations, individual compounds of high priority, a su...

349

Exchange of volatile organic compounds in the boreal forest floor  

NASA Astrophysics Data System (ADS)

Terrestrial ecosystems, mainly plants, emit large amounts of volatile organic compounds (VOCs) into the atmosphere. In addition to plants, VOCs also have less-known sources, such as soil. VOCs are a very diverse group of reactive compounds, including terpenoids, alcohols, aldehydes and ketones. Due to their high reactivity, VOCs take part in formation and growth of secondary organic aerosols in the atmosphere and thus affect also Earth's radiation balance (Kulmala et al. 2004). We have studied boreal soil and forest floor VOC fluxes with chamber and snow gradient techniques we were developed. Spatial and temporal variability in VOC fluxes was studied with year-round measurements in the field and the sources of boreal soil VOCs in the laboratory with fungal isolates. Determination of the compounds was performed mass spectrometrically. Our results reveal that VOCs from soil are mainly emitted by living roots, above- and belowground litter and microbes. The strongest source appears to be litter, in which both plant residuals and decomposers play a role in the emissions. Soil fungi showed high emissions of lighter VOCs, like acetone, acetaldehyde and methanol, from isolates. Temperature and moisture are the most critical physical factors driving VOC fluxes. Since the environment in boreal forests undergoes strong seasonal changes, the VOC flux strength of the forest floor varies markedly during the year, being highest in spring and autumn. The high spatial heterogeneity of the forest floor was also clearly visible in VOC fluxes. The fluxes of other trace gases (CO2, CH4 and N2O) from soil, which are also related to the soil biological activity and physical conditions, did not show correlations with the VOC fluxes. These results indicate that emissions of VOCs from the boreal forest floor account for as much as several tens of percent, depending on the season, of the total forest ecosystem VOC emissions. This emphasises that forest floor compartment should be taken into consideration when assessing ecosystem level VOC fluxes. These results can be utilized also in air chemistry models, which are almost entirely lacking the below-canopy compartment. Kulmala, M., Suni, T., Lehtinen, K.E.J., Dal Maso, M., Boy, M., Reissell, A., Rannik, Ü., Aalto, P., Keronen, P., Hakola, H., Bäck, J., Hoffmann, T., Vesala, T. & Hari, P. 2004. A new feedback mechanism linking forests, aerosols, and climate. Atmospheric Chemistry and Physics 4: 557-562.

Aaltonen, Hermanni; Bäck, Jaana; Pumpanen, Jukka; Pihlatie, Mari; Hakola, Hannele; Hellén, Heidi; Aalto, Juho; Heinonsalo, Jussi; Kajos, Maija K.; Kolari, Pasi; Taipale, Risto; Vesala, Timo

2013-04-01

350

The seasonal variation in bioactive compounds content in juice from organic and non-organic tomatoes.  

PubMed

A specific objective of this paper was to evaluate seasonal changes in bioactive compounds level (carotenoids and polyphenols) in juice prepared from organic and non-organic tomatoes in Poland. In the examined tomato juice, the content of dry matter, vitamin C, carotenoids as well as polyphenols (by HPLC method) has been measured. The presented results indicate the impact of the growing system and the year of production on the composition of tomato juice. The organic tomato juice contained significantly more beta-carotene, chlorogenic acid, rutin as well as more total phenolic acids, gallic acid, p-coumaric acid, total flavonoids, quercetin-3-O-glucoside and quercetin in comparison with the non-organic. The tomato juice from 2008 contained significantly more carotenoids and some flavonoids compared to the one produced in 2009, which contained significantly more dry matter, vitamin C, as well as quercetin and it derivatives. PMID:23609833

Hallmann, Ewelina; Lipowski, Janusz; Marsza?ek, Krystian; Rembia?kowska, Ewa

2013-06-01

351

Identification of volatile organic compounds in human cerumen.  

PubMed

We report here the initial examination of volatile organic compounds (VOCs) emanating from human earwax (cerumen). Recent studies link a single nucleotide polymorphism (SNP) in the adenosine triphosphate (ATP) binding cassette, sub-family C, member 11 gene (ABCC11) to the production of different types of axillary odorants and cerumen. ABCC11 encodes an ATP-driven efflux pump protein that plays an important function in ceruminous apocrine glands of the auditory canal and the secretion of axillary odor precursors. The type of cerumen and underarm odor produced by East Asians differ markedly from that produced by non-Asians. In this initial report we find that both groups emit many of the same VOCs but differ significantly in the amounts produced. The principal odorants are volatile organic C2-to-C6 acids. The physical appearance of cerumen from the two groups also matches previously reported ethnic differences, viz., cerumen from East Asians appears dry and white while that from non-Asians is typically wet and yellowish-brown. PMID:24572763

Prokop-Prigge, Katharine A; Thaler, Erica; Wysocki, Charles J; Preti, George

2014-03-15

352

DDTs and other chlorinated organic pesticides and polychlorinated biphenyls pollution in the surface sediments of Keratsini harbour, Saronikos gulf, Greece.  

PubMed

Sediment samples were collected from Keratsini harbour, Saronikos gulf, Greece and were analysed for chlorinated organic pesticides (DDTs, HCB, Lindane) and polychlorinated biphenyls (PCBs). High total DDTs values were detected in all the sediments samples ranging from 9.1 to 75.6 mug/g, dry weight. PCBs concentrations range from 47.8 to 351.8 ng/g. The results and especially the high concentrations of DDTs reflect the influence of the industrial and urban wastes in the pollution for the Keratsini harbour environment. PMID:15907494

Galanopoulou, Stavroula; Vgenopoulos, Andreas; Conispoliatis, Nikolaos

2005-05-01

353

TOXICOLOGY OF PESTICIDES  

EPA Science Inventory

This report includes the results of five toxicological studies of pesticide compounds conducted by the Institute for Medical Research and Occupational Health, Zagreb, Yugoslavia. In the first study, the reactions of two groups of esterases (cholinesterases and arylesterases) with...

354

Biodegradation of organic compounds sequestered in organic solids or in nanopores within silica particles  

Microsoft Academic Search

A study was conducted using model solids to determine whether the time-dependent decline in availability for biodegradation of organic pollutants in soil might result from the entrapment of these compounds in porous or nonporous solids. A strain of Pseudomonas mineralized phenanthrene in solid alkanes containing 18 to 32 carbons, three waxes, and low-molecular-weight polycaprolactone, polyethylene, and polypropylene. The rates were

Paul B. Hatzinger; Martin Alexander

1997-01-01

355

Emission and Chemical Transformation of Biogenic Volatile Organic Compounds (echo)  

NASA Astrophysics Data System (ADS)

Forests are complex sources of biogenic volatile organic compounds (VOC) in the planetary boundary layer. The impact of biogenic VOC on tropospheric photochem- istry, air quality, and the formation of secondary products affects our climate on a regional and global scale but is far from being understood. A considerable lack of knowledge exists concerning a forest stand as a net source of reactive trace com- pounds, which are transported directly into the planetary boundary layer (PBL). In particular, little is known about the amounts of VOC which are processed within the canopy. The goal of ECHO, which is presented in this poster, is to investigate these questions and to improve our understanding of biosphere-atmosphere interactions and their effects on the PBL. The investigation of emissions, chemical processing and vertical transport of biogenic VOC will be carried out in and above a mixed forest stand in Jülich, Germany. A large set of trace gases, free radicals and meteorologi- cal parameters will be measured at different heights in and above the canopy, covering concentrations of VOC, CO, O3, organic nitrates und NOx as well as organic aerosols. For the first time concentration profiles of OH, HO2, RO2 und NO3 radicals will be measured as well together with the actinic UV radiation field and photolysis frequen- cies of all relevant radical precursors (O3, NO2, peroxides, oxygenated VOC). The different tasks of the field experiments will be supported by simulation experiments investigating the primary emission and the uptake of VOC by the plants in stirred tank reactors, soil parameters and soil emissions in lysimeter experiments, and the chem- ical processing of the trace gases as observed in and above the forest stand in the atmosphere simulation chamber SAPHIR. The planning and interpretation of the field experiments is supported by simulations of the field site in a wind tunnel.

Koppmann, R.; Hoffmann, T.; Kesselmeier, J.; Schatzmann, M.

356

FACTORS CONTROLLING THE EMISSIONS OF MONOTERPENES AND OTHER VOLATILE ORGANIC COMPOUNDS  

EPA Science Inventory

Plants contain a number of volatile organic compounds, including isoprene, mono- and sesquiterpenes, alcohols, aldehydes, ketones, and esters. ndividual plant species have unique combinations of these compounds; consequently, the emission pattern for each species is also specific...

357

Assessing Diet as a Modifiable Risk Factor for Pesticide Exposure  

PubMed Central

The effects of pesticides on the general population, largely as a result of dietary exposure, are unclear. Adopting an organic diet appears to be an obvious solution for reducing dietary pesticide exposure and this is supported by biomonitoring studies in children. However, results of research into the effects of organic diets on pesticide exposure are difficult to interpret in light of the many complexities. Therefore future studies must be carefully designed. While biomonitoring can account for differences in overall exposure it cannot necessarily attribute the source. Due diligence must be given to appropriate selection of participants, target pesticides and analytical methods to ensure that the data generated will be both scientifically rigorous and clinically useful, while minimising the costs and difficulties associated with biomonitoring studies. Study design must also consider confounders such as the unpredictable nature of chemicals and inter- and intra-individual differences in exposure and other factors that might influence susceptibility to disease. Currently the most useful measures are non-specific urinary metabolites that measure a range of organophosphate and synthetic pyrethroid insecticides. These pesticides are in common use, frequently detected in population studies and may provide a broader overview of the impact of an organic diet on pesticide exposure than pesticide-specific metabolites. More population based studies are needed for comparative purposes and improvements in analytical methods are required before many other compounds can be considered for assessment. PMID:21776202

Oates, Liza; Cohen, Marc

2011-01-01

358

Selective Sorption of Dissolved Organic Carbon Compounds by Temperate Soils  

PubMed Central

Background Physico-chemical sorption onto soil minerals is one of the major processes of dissolved organic carbon (OC) stabilization in deeper soils. The interaction of DOC on soil solids is related to the reactivity of soil minerals, the chemistry of sorbate functional groups, and the stability of sorbate to microbial degradation. This study was conducted to examine the sorption of diverse OC compounds (D-glucose, L-alanine, oxalic acid, salicylic acid, and sinapyl alcohol) on temperate climate soil orders (Mollisols, Ultisols and Alfisols). Methodology Equilibrium batch experiments were conducted using 0–100 mg C L?1 at a solid-solution ratio of 1?60 for 48 hrs on natural soils and on soils sterilized by ?-irradiation. The maximum sorption capacity, Qmax and binding coefficient, k were calculated by fitting to the Langmuir model. Results Ultisols appeared to sorb more glucose, alanine, and salicylic acid than did Alfisols or Mollisols and the isotherms followed a non-linear pattern (higher k). Sterile experiments revealed that glucose and alanine were both readily degraded and/or incorporated into microbial biomass because the observed Qmax under sterile conditions decreased by 22–46% for glucose and 17–77% for alanine as compared to non-sterile conditions. Mollisols, in contrast, more readily reacted with oxalic acid (Qmax of 886 mg kg?1) and sinapyl alcohol (Qmax of 2031 mg kg?1), and no degradation was observed. The reactivity of Alfisols to DOC was intermediate to that of Ultisols and Mollisols, and degradation followed similar patterns as for Ultisols. Conclusion This study demonstrated that three common temperate soil orders experienced differential sorption and degradation of simple OC compounds, indicating that sorbate chemistry plays a significant role in the sorptive stabilization of DOC. PMID:23209742

Jagadamma, Sindhu; Mayes, Melanie A.; Phillips, Jana R.

2012-01-01

359

Quantum Magnetism and possible BEC in an organic Nickel compound  

NASA Astrophysics Data System (ADS)

I will review recent experimental and theoretical work on the S=1 quantum magnet, NiCl2-4SC(NH2)2. [1] This compound exhibits field-induced XY antiferromagnetism for magnetic fields along the tetragonal c-axis between Hc1 = 2.1 and Hc2 = 12.6 T. The axial symmetry of the spin environment allows us to understand the quantum phase transitions at Hc1 and Hc2 in terms of Bose-Einstein condensation (BEC) of spin levels. Here the tuning parameter for BEC transition is the magnetic field and not the temperature. Specific heat, magnetocaloric effect, and magnetization data at low temperatures confirm the predicted behavior for a BEC: Hc-Hc1˜ T^? and M(Hc1) ˜ T^? where ? = 3/2. I will also present magnetostriction data [2] taken at dilution refrigerator temperatures that show significant magnetoelastic coupling and magnetic-order-induced modifications of the lattice parameters in this soft organic compound. The data are well-described by Quantum Monte Carlo calculations, allowing us to make a quantitative determination of the magnetoelastic coupling, and also extract the spin-spin correlation function from the magnetostriction data. [1] V. S. Zapf, D. Zocco, B. R. Hansen, M. Jaime, N. Harrison, C. D. Batista, M. Kenzelmann, C. Niedermayer, A. Lacerda, and A. Paduan-Filho, Phys. Rev. Lett. 96, 077204 (2006).[2] V. S. Zapf, V. Correa, C. D. Batista, T. Murphy, E. D. Palm, M. Jaime, S. Tozer, A. Lacerda, A. Paduan-Filho, ``Magnetostriction in the Bose-Einstein Condensate quantum magnet NiCl2-4SC(NH2)2,'' cond-mat/0611229.

Zapf, Vivien

2007-03-01

360

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

USGS Publications Warehouse

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

Buchmiller, R.C.

1989-01-01

361

Reactivity of group IV (100) semiconductor surfaces towards organic compounds  

NASA Astrophysics Data System (ADS)

The reactions of simple and multifunctional organic compounds with the clean silicon, germanium, and diamond (100)-2 x 1 semiconductor surfaces have been investigated using a combination of multiple internal reflection infrared spectroscopy and quantum chemistry density functional theory calculations. From these studies, an improved understanding of the atomic level reactivity of these semiconductor surfaces has been obtained, along with insights into how to achieve their selective coupling with organics of desired and varied functionality. In addition to the Si(100) and Ge(100) surfaces, our results show that cycloaddition chemistry can also be extended to the diamond (100) surface. At room temperature, 1,3-butadiene was found to form a Diels-Alder product with the diamond (100) surface, as evidenced by isotopic substitution experiments and comparison of the surface adduct with its direct molecular analogue, cyclohexene. The reactions of other classes of molecules in addition to alkenes on the Si(100) and Ge(100) surfaces, including a series of five-membered cyclic amines, were also examined. For tertiary aliphatic amines on Si(100) and both secondary and tertiary aliphatic amines on Ge(100), a majority of the molecules were observed to become stably trapped in dative-bonded precursor states rather than form energetically favorable dissociation products. For pyrrole, aromaticity was found to play a defining role in its reactivity, and a comparison of its molecular and surface reactivity reveals interesting similarities. To probe the factors controlling the selectivity of organic reactions on clean semiconductor surfaces, the adsorption of acetone and a series of unsaturated ketones was also investigated. The reaction of acetone on Ge(100) was found to be under thermodynamic control at room temperature, resulting in the formation of an "ene" product rather than the kinetically favored [2+2] C=O cycloaddition product previously observed on the Si(100) surface. In contrast to the silicon and diamond surfaces, thermodynamic control on the germanium surface is facilitated by the reversibility of weak adsorption. For the unsaturated ketones, enhanced selectivity on Ge(100) in comparison with Si(100) was observed. The results can be explained by differences between the two surfaces in both thermodynamic and kinetic factors, and suggest that germanium may be a superior material for selective organic functionalization.

Wang, George T.

362

Characterization of selected volatile organic compounds, polycyclic aromatic hydrocarbons and carbonyl compounds at a roadside monitoring station  

NASA Astrophysics Data System (ADS)

Volatile organic compounds (VOCs), PAHs and carbonyl compounds are the major toxic components in Hong Kong. Emissions from motor vehicles have been one of the primary pollution sources in the metropolitan areas throughout Hong Kong for a long time. A 1-yr monitoring program for VOCs, PAHs and carbonyl compounds had been performed at a roadside urban station at Hong Kong Polytechnic University in order to determine the variations and correlations of each selected species (VOCs, PAHs and carbonyl compounds). This study is aimed to analyze toxic volatile organic compounds (benzene, toluene, ethylbenzene and xylene), two carbonyl compounds (formaldehyde, acetaldehyde), and selective polycyclic aromatic hydrocarbons. The monitoring program started from 16 April 1999 to 30 March 2000. Ambient VOC concentrations, many of which originate from the same sources as particulate PAHs and carbonyls compounds, show significant quantities of benzene, toluene and xylenes. Correlations and multivariate analysis of selected gaseous and particulate phase organic pollutants were performed. Source identification by principle component analysis and hierarchical cluster analysis allowed the identification of four sources (factors) for the roadside monitoring station. Factor 1 represents the effect of diesel vehicle exhaust. Factor 2 shows the contribution of aromatic compounds. Factor 3 explains photochemical products—formaldehyde and acetaldehyde. Factor 4 explains the effect of gasoline vehicle exhaust.

Ho, K. F.; Lee, S. C.; Chiu, Gloria M. Y.

363

Adsorption of volatile organic compounds in porous metal-organic frameworks functionalized by polyoxometalates  

SciTech Connect

The functionalization of porous metal-organic frameworks (Cu{sub 3}(BTC){sub 2}) was achieved by incorporating Keggin-type polyoxometalates (POMs), and further optimized via alkali metal ion-exchange. In addition to thermal gravimetric analysis, IR, single-crystal X-ray diffraction, and powder X-ray diffraction, the adsorption properties were characterized by N{sub 2} and volatile organic compounds (VOCs) adsorption measurements, including short-chain alcohols (C<4), cyclohexane, benzene, and toluene. The adsorption enthalpies estimated by the modified Clausius-Clapeyron equation provided insight into the impact of POMs and alkali metal cations on the adsorption of VOCs. The introduction of POMs not only improved the stability, but also brought the increase of adsorption capacity by strengthening the interaction with gas molecules. Furthermore, the exchanged alkali metal cations acted as active sites to interact with adsorbates and enhanced the adsorption of VOCs. - Graphical Abstract: The adsorption behavior of volatile organic compounds in porous metal-organic frameworks functionalized by polyoxometalates has been systematically evaluated. Highlights: > Functionalization of MOFs was achieved by incorporating Keggin-type POMs. > Introduction of POMs improved the thermal stability and adsorption capacity. > Alkali metal ion-exchange modified the inclusion state and also enhanced the adsorption. > Adsorption enthalpies were estimated to study the impact of POMs and alkali metal cations.

Ma Fengji [Key Laboratory of Polyoxometalates Science of the Ministry of Education, College of Chemistry, Northeast Normal University, Changchun 130024 (China); Liu Shuxia, E-mail: liusx@nenu.edu.cn [Key Laboratory of Polyoxometalates Science of the Ministry of Education, College of Chemistry, Northeast Normal University, Changchun 130024 (China); Liang Dadong; Ren Guojian; Wei Feng; Chen Yaguang; Su Zhongmin [Key Laboratory of Polyoxometalates Science of the Ministry of Education, College of Chemistry, Northeast Normal University, Changchun 130024 (China)

2011-11-15

364

IDENTIFICATION AND QUANTIFICATION OF AEROSOL POLAR OXYGENATED COMPOUNDS BEARING CARBOXYLIC OR HYDROXYL GROUPS. 2. ORGANIC TRACER COMPOUNDS FROM MONOTERPENES  

EPA Science Inventory

A comparison was made of polar organic compounds found in the field with those produced in secondary organic aerosol from laboratory irradiations of natural hydrocarbons and oxides of nitrogen. The field samples comprised atmospheric particulate matter (PM2.5) collect...

365

TREATMENT OF VOLATILE ORGANIC COMPOUNDS IN DRINKING WATER  

EPA Science Inventory

Volatile chlorinated and non-chlorinated compounds occur in both untreated and treated drinking water. Because volatilization is restricted, ground waters rather than surface waters are more likely to have high concentrations of these compounds. This document reviews properties, ...

366

Precipitate hydrolysis process for the removal of organic compounds from nuclear waste slurries  

DOEpatents

A process for removing organic compounds from a nuclear waste slurry comprising reacting a mixture of radioactive waste precipitate slurry and an acid in the presence of a catalytically effective amount of a copper(II) catalyst whereby the organic compounds in the precipitate slurry are hydrolyzed to form volatile organic compounds which are separated from the reacting mixture. The resulting waste slurry, containing less than 10 percent of the original organic compounds, is subsequently blended with high level radioactive sludge land transferred to a vitrification facility for processing into borosilicate glass for long-term storage. 2 figs., 3 tabs.

Doherty, J.P.; Marek, J.C.

1987-02-25

367

Precipitate hydrolysis process for the removal of organic compounds from nuclear waste slurries  

DOEpatents

A process for removing organic compounds from a nuclear waste slurry comprising reacting a mixture of radioactive waste precipitate slurry and an acid in the presence of a catalytically effective amount of a copper (II) catalyst whereby the organic compounds in the precipitate slurry are hydrolyzed to form volatile organic compounds which are separated from the reacting mixture. The resulting waste slurry, containing less than 10 percent of the orginal organic compounds, is subsequently blended with high level radioactive sludge and transferred to a virtrification facility for processing into borosilicate glass for long-term storage.

Doherty, Joseph P. (Elkton, MD); Marek, James C. (Augusta, GA)

1989-01-01

368

Secondary organic aerosol formation from intermediate-volatility organic compounds: cyclic, linear, and branched alkanes.  

PubMed

Intermediate volatility organic compounds (IVOCs) are an important class of secondary organic aerosol (SOA) precursors that have not been traditionally included in chemical transport models. A challenge is that the vast majority of IVOCs cannot be speciated using traditional gas chromatography-based techniques; instead they are classified as an unresolved complex mixture (UCM) that is presumably made up of a complex mixture of branched and cyclic alkanes. To better understand SOA formation from IVOCs, a series of smog chamber experiments was conducted with different alkanes, including cyclic, branched, and linear compounds. The experiments focused on freshly formed SOA from hydroxyl (OH) radical-initiated reactions under high-NO(x) conditions at typical atmospheric organic aerosol concentrations (C(OA)). SOA yields from cyclic alkanes were comparable to yields from linear alkanes three to four carbons larger in size. For alkanes with equivalent carbon numbers, branched alkanes had the lowest SOA mass yields, ranging between 0.05 and 0.08 at a C(OA) of 15 ?g m(-3). The SOA yield of branched alkanes also depends on the methyl branch position on the carbon backbone. High-resolution aerosol mass spectrometer data indicate that the SOA oxygen-to-carbon ratios were largely controlled by the carbon number of the precursor compound. Depending on the precursor size, the mass spectrum of SOA produced from IVOCs is similar to the semivolatile-oxygenated and hydrocarbon-like organic aerosol factors derived from ambient data. Using the new yield data, we estimated SOA formation potential from diesel exhaust and predict the contribution from UCM vapors to be nearly four times larger than the contribution from single-ring aromatics and comparable to that of polycyclic aromatic hydrocarbons after several hours of oxidation at typical atmospheric conditions. Therefore, SOA from IVOCs may be an important contributor to urban OA and should be included in SOA models; the yield data presented in this study are suitable for such use. PMID:22823284

Tkacik, Daniel S; Presto, Albert A; Donahue, Neil M; Robinson, Allen L

2012-08-21

369

Flux measurements of volatile organic compounds from an urban landscape  

NASA Astrophysics Data System (ADS)

Direct measurements of volatile organic compound (VOC) emissions that include all sources in urban areas are a missing requirement to evaluate emission inventories and constrain current photochemical modelling practices. Here we demonstrate the use of micrometeorological techniques coupled with fast-response sensors to measure urban VOC fluxes from a neighbourhood of Mexico City, where the spatial variability of surface cover and roughness is high. Fluxes of olefins, methanol, acetone, toluene and C2-benzenes were measured and compared with the local gridded emissions inventory. VOC fluxes exhibited a clear diurnal pattern with a strong relationship to vehicular traffic. Recent photochemical modelling results suggest that VOC emissions are significantly underestimated in Mexico City, but for the olefin class, toluene, C2-benzenes, and acetone fluxes measured in this work, the results show general agreement with the gridded emissions inventory. While these measurements do not address the full suite of VOC emissions, the comparison with the inventory suggests that other explanations may be needed to explain the photochemical modelling results.

Velasco, E.; Lamb, B.; Pressley, S.; Allwine, E.; Westberg, H.; Jobson, B. T.; Alexander, M.; Prazeller, P.; Molina, L.; Molina, M.

2005-10-01

370

Elimination of volatile organic compounds by biofiltration: a review.  

PubMed

Volatile organic compounds (VOCs) are pollutants that are responsible for the formation of the tropospheric ozone, one of the precursors of smog. VOCs are emitted by various industries including chemical plants, pulp and paper mills, pharmaceuticals, cosmetics, electronics and agri-food industries. Some VOCs cause odor pollution while many of them are harmful to environment and human or animal health. For the removal of VOCs, biofiltration, a biological process, has proved to be reliable when properly operated. This process has therefore been widely applied in Europe and North America. The main advantages associated with the use of biofiltration are related to its set-up, maintenance, and operating costs which are usually lower than those related to other VOCs control technologies and because it is less harmful for the environment than conventional processes like incineration. In the present paper, the main parameters (type, moisture, pH, and temperature of filter bed, microbial population, nutrients concentrations, and VOCs' inlet load) to be controlled during the biofiltration are identified and described in detail. The main phenomena involved in biofiltration are also discussed. For improving the efficiency of VOC control biotechnology, new techniques are now proposed that include the use of membranes, biphasic reactors, UV photolysis, and many others. PMID:18351227

Nikiema, Josiane; Dastous, Paul-André; Heitz, Michèle

2007-01-01

371

Development of novel biofilters for treatment of volatile organic compounds  

SciTech Connect

Biofiltration involves contacting a contaminated gas stream with immobilized microorganisms in a contactor to biodegrade the contaminants. It is emerging as an attractive technology for removing low concentrations (i.e., less than 800 ppmv) of volatile organic chemicals (VOCs) from air. Compared with other technologies, biofiltration fully mineralizes the contaminants, is inexpensive and reliable, and requires no posttreatment. In the study described in this paper, four types of media consisting of porous ceramic monoliths with several straight passages were studied to determine the effects of adsorptive and nonadsorptive media on biofilter startup time, dynamic response to step changes in inlet substrate concentration, biofilm adherence, and overall VOC-removal efficiency. Volatile compounds studied were benzene, toluene, ethylbenzene, m-xylene, and o-xylene. Adsorbing media such as activated carbon, when compared with nonadsorbing media such as ceramic, exhibit faster biofilter startup, are more stable to dynamic changes in inlet concentration, and attain higher VOC-removal efficiencies due to better adherence of biofilm on media surfaces.

Bishop, D.F. [Environmental Protection Agency, Cincinnati, OH (United States). National Risk Management Research Lab.; Govind, R. [Univ. of Cincinnati, OH (United States). Dept. of Chemical Engineering

1995-12-31

372

Volatile organic compound monitoring by photo acoustic radiometry  

SciTech Connect

Two methods for sampling and analyzing volatile organics in subsurface pore gas were developed for use at the Hazardous Waste Disposal Site at Los Alamos National Laboratory. One is Thermal Desorption Gas Chromatography Mass Spectrometry (TDGCMS), the other is Photoacoustic Radiometry (PAR). Presented here are two years worth of experience and lessons learned as both techniques matured. The sampling technique is equally as important as the analysis method. PAR is a nondispersive infrared technique utilizing band pass filters in the region from 1 to 15 {mu}m. A commercial instrument, the Model 1302 Multigas Analyzer, made by Bruel and Kjaer, was adapted for field use. To use the PAR there must be some a priori knowledge of the constellation of analytes to be measured. The TDGCMS method is sensitive to 50 analytes. Hence TDGCMS is used in an initial survey of the site to determine what compounds are present and at what concentration. Once the major constituents of the soil-gas vapor plume are known the PAR can be configured to monitor for the five analytes of most interest. The PAR can analyse a sample in minutes, while in the field. The PAR is also quite precise in controlled situations.

Sollid, J.E.; Trujillo, V.L.; Limback, S.P.; Woloshun, K.A.

1995-12-01

373

Cellular uptake of lipoproteins and persistent organic compounds-An update and new data  

SciTech Connect

There are a number of interactions related to the transport of lipophilic xenobiotic compounds in the blood stream of mammals. This paper will focus on the interactions between lipoproteins and persistent organic pollutants (POPs) and how these particles are taken up by cells. A number of POPs including the pesticide p,p'-dichlorodiphenyltrichloroethane (DDT), and especially its metabolite p,p'-dichlorodiphenyldichloroethene (DDE), interacts with nuclear hormone receptors causing these to malfunction, which in turn results in a range of deleterious health effects in humans. The aim of the present study was to determine the role of lipoprotein receptors in mouse embryonic fibroblast (MEF) cells in conjunction with uptake of DDT-lipoprotein complexes from supplemented media in vitro. Uptake of DDT by MEF cells was investigated using MEF1 cells carrying the receptors low-density lipoprotein receptor-related protein (LRP) and low-density lipoprotein receptor (LDLR) present and MEF4 cells with no LRP and LDLR expression. Cells were incubated together with the complex of low-density lipoproteins (LDL) and [{sup 14}C]DDT. The receptor function was further evaluated by adding the 40 kDa receptor-associated protein (RAP) which blocks receptor activity. The results showed that [{sup 14}C]DDT uptake was decreasing when the LDL concentration was increasing. There was no strong evidence for a receptor-mediated uptake of the [{sup 14}C]DDT-lipoprotein complex. To conclude, DDT travels in the blood stream and can cross cell membranes while being transported as a DDT-lipoprotein complex. The lipoproteins do not need receptors to cross cell membranes since passive diffusion constitutes a major passageway.

Hjelmborg, Philip Sebastian [Department of Environmental and Occupational medicine, Unit of Cellular and Molecular Toxicology, Institute of Public Health, University of Aarhus, Aarhus, Vennelyst Boulevard 6, Bygn 1260, 8000 Aarhus C, DK (Denmark); Andreassen, Thomas Kjaergaard [Institute of Medical Biochemistry, University of Aarhus, Aarhus (Denmark); Bonefeld-Jorgensen, Eva Cecilie [Department of Environmental and Occupational medicine, Unit of Cellular and Molecular Toxicology, Institute of Public Health, University of Aarhus, Aarhus, Vennelyst Boulevard 6, Bygn 1260, 8000 Aarhus C, DK (Denmark)], E-mail: ebj@mil.au.dk

2008-10-15

374

Enantiomer distribution of major chiral volatile organic compounds in selected types of herbal honeys.  

PubMed

In this article, volatile organic compounds in 14 honey samples (rosemary, eucalyptus, orange, thyme, sage, and lavender) were identified. Volatile organic compounds were extracted using a solid phase microextraction method followed by gas chromatography connected with mass spectrometry analysis. The studied honey samples were compared based on their volatile organic compounds composition. In total, more than 180 compounds were detected in the studied samples. The detected compounds belong to various chemical classes such as terpenes, alcohols, acids, aldehydes, ketones, esters, norisoprenoids, benzene and furane derivatives, and organic compounds containing sulfur and nitrogen heteroatom. Ten chiral compounds (linalool, trans-linalool oxide, cis-linalool oxide, 4-terpineol, ?-terpineol, hotrienol, and four stereoisomers of lilac aldehydes) were selected for further chiral separation. PMID:25099214

Pažitná, Alexandra; Džúrová, Jana; Spánik, Ivan

2014-10-01

375

Determination of the pesticides considered as endocrine-disrupting compounds (EDCs) by solid-phase extraction followed by gas chromatography with electron capture and mass spectrometric detection.  

PubMed

An SPE method followed by GC-electron capture detection (ECD) with confirmation by MS for the trace determination of four pesticides considered as endocrine-disrupting compounds (EDCs) in natural waters and sediments has been developed. Target analytes, fenarimol, fenvalerate, pendimethalin, and vinclozolin, belong to different chemical groups and are used mainly in agriculture. In the present study, analysis employs an offline SPE step for the extraction of the target analytes from natural waters. Sonication and subsequent SPE clean-up was used for extraction and purification of the sediment samples which were finally treated with activated copper powder. The type of SPE disk, eluents as well as solution parameters including pH value, and concentrations of salts and humic substances were examined for the efficiency of the method. The recoveries of all pesticides were in relatively high levels, ranging from 75 to 97% for waters and 71 to 84% for sediment samples. Both methods were applied to real water and sediment samples and the presence of the tested compounds was investigated. PMID:17638344

Valsamaki, Vasiliki I; Sakkas, Vasilios A; Albanis, Triantafyllos A

2007-08-01

376

Volatile organic compounds of polyethylene vinyl acetate plastic are toxic to living organisms.  

PubMed

Volatile organic compounds (VOCs) in polyvinyl chloride (PVC) plastic products readily evaporate; as a result, hazardous gases enter the ecosystem, and cause cancer in humans and other animals. Polyethylene vinyl acetate (PEVA) plastic has recently become a popular alternative to PVC since it is chlorine-free. In order to determine whether PEVA is harmful to humans, this research employed the freshwater oligochaete Lumbriculus variegatus as a model to compare their oxygen intakes while they were exposed to the original stock solutions of PEVA, PVC or distilled water at a different length of time for one day, four days or eight days. During the exposure periods, the oxygen intakes in both PEVA and PVC groups were much higher than in the distilled water group, indicating that VOCs in both PEVA and PVC were toxins that stressed L. variegatus. Furthermore, none of the worms fully recovered during the24-hr recovery period. Additionally, the L. variegatus did not clump together tightly after four or eight days' exposure to either of the two types of plastic solutions, which meant that both PEVA and PVC negatively affected the social behaviors of these blackworms. The LD50 tests also supported the observations above. For the first time, our results have shown that PEVA plastic has adverse effects on living organisms, and therefore it is not a safe alternative to PVC. Further studies should identify specific compounds causing the adverse effects, and determine whether toxic effect occurs in more complex organisms, especially humans. PMID:25242410

Meng, Tingzhu Teresa

2014-01-01

377

Effects of polar and nonpolar groups on the solubility of organic compounds in soil organic matter  

USGS Publications Warehouse

Vapor sorption capacities on a high-organic-content peat, a model for soil organic matter (SOM), were determined at room temperature for the following liquids: n-hexane, 1,4-dioxane, nitroethane, acetone, acetonitrile, 1-propanol, ethanol, and methanol. The linear organic vapor sorption is in keeping with the dominance of vapor partition in peat SOM. These data and similar results of carbon tetrachloride (CT), trichloroethylene (TCE), benzene, ethylene glycol monoethyl ether (EGME), and water on the same peat from earlier studies are used to evaluate the effect of polarity on the vapor partition in SOM. The extrapolated liquid solubility from the vapor isotherm increases sharply from 3-6 wt % for low-polarity liquids (hexane, CT, and benzene) to 62 wt % for polar methanol and correlates positively with the liquid's component solubility parameters for polar interaction (??P) and hydrogen bonding (??h). The same polarity effect may be expected to influence the relative solubilities of a variety of contaminants in SOM and, therefore, the relative deviations between the SOM-water partition coefficients (Kom) and corresponding octanol-water partition coefficients (Kow) for different classes of compounds. The large solubility disparity in SOM between polar and nonpolar solutes suggests that the accurate prediction of Kom from Kow or Sw (solute water solubility) would be limited to compounds of similar polarity.

Chiou, C.T.; Kile, D.E.

1994-01-01

378

Respiration corrections for bacterial uptake of dissolved organic compounds in natural waters  

Microsoft Academic Search

The uptake of %-labeled organic compounds has been used by many workers to study heterotrophic microorganisms in natural waters. IIowevcr, if flux rates of organic com- pounds are to be mcasurcd, the loss of '\\

JOHN E. HOBBIE; CLAUDE C. CRAWFORD

1969-01-01

379

EVALUATION OF THE WALKTHROUGH SURVEY METHOD FOR DETECTION OF VOLATILE ORGANIC COMPOUND LEAKS  

EPA Science Inventory

During 1978 and 1979, the Emission Standards and Engineering Division of EPA's Office of Air Quality Planning and Standards conducted a fugitive volatile organic compound (VOC) emission sampling program in organic chemical manufacturing plants and petroleum refineries. As a part ...

380

Sediment-deposition rates and organic compounds in bottom sediment at four sites in Lake Mead, Nevada, May 1998  

USGS Publications Warehouse

In May 1998 the U.S. Geological Survey, in cooperation with the University of Nevada, Las Vegas, investigated rates of sediment deposition and concentrations of selected synthetic organic compounds at four sites in Lake Mead. Sediment cores were extracted from two sites (one shallow and one deep) in Las Vegas Bay, from one site in the Overton Arm, and from one site near the historic confluence of the Colorado and Virgin Rivers. The sediment cores were age-dated using cesium-137 and were analyzed for the presence of organochlorine compounds (pesticides and degradation products, polychlorinated biphenyls, dioxins, and furans) and for semivolatile organic compounds (polycyclic aromatic hydrocarbons and phenols). Sediment-deposition rates after impoundment of the Colorado River by Hoover Dam were determined by measuring the accumulation of mass during three different periods: (1) from the approximate impoundment date for each site (1935-37) to the initial occurrence of cesium-137 in the atmosphere (1952); (2) from 1952 to the maximum concentration of cesium-137 in the atmosphere (1964); and (3) from 1964 to the collection date of the sample (1998). Sediment-deposition rates for the entire post-impoundment period (1935-98) averaged 1.45 (g/cm2)/yr (grams per square centimeter per year) at the Las Vegas Bay shallow site, 1.25 (g/cm2)/yr at the Las Vegas Bay deep site, 0.80 (g/cm2)/yr at the Overton Arm site, and 0.65 (g/cm2)/yr at the Colorado and Virgin Rivers confluence site. Sediment-deposition rates after impoundment of the Colorado River by Hoover Dam were determined by measuring the accumulation of mass during three different periods: (1) from the approximate impoundment date for each site (1935-37) to the initial occurrence of cesium-137 in the atmosphere (1952); (2) from 1952 to the maximum concentration of cesium-137 in the atmosphere (1964); and (3) from 1964 to the collection date of the sample (1998). Sediment-deposition rates for the entire post-impoundment period (1935-98) averaged 1.45 (g/cm2)/yr (grams per square centimeter per year) at the Las Vegas Bay shallow site, 1.25 (g/cm2)/yr at the Las Vegas Bay deep site, 0.80 (g/cm2)/yr at the Overton Arm site, and 0.65 (g/cm2)/yr at the Colorado and Virgin Rivers confluence site. Total numbers of synthetic organic compounds detected in sediment samples were 48 at the Las Vegas Bay shallow site, 57 at the Las Vegas Bay deep site, 26 at the Overton Arm site, and 31 at the Colorado and Virgin Rivers confluence site. The most commonly detected organochlorine pesticide and polychlorinated biphenyl compounds were dichlorodiphenyldichloroethane and dichlorodiphenyldichloroethylene. The most commonly detected dioxin compounds were tetrachlorodibenzo-p-dioxin and octochlorodibenzo-p-dioxin. The most commonly detected furan compounds were tetrachlorodibenzofuran and octochlorodibenzofuran. The most commonly detected polycyclic aromatic hydrocarbons included perylene, benzo[g,h,i]perylene, 2,6-dimethylnaphthalene, and indeno[1,2,3-c,d]pyrene. The most commonly detected phenol compound was phenol.

Covay, K.J.; Beck, D.A.

2001-01-01

381

Geochemistry of volatile organic compounds in seawater: Mesocosm experiments with 14C-model compounds  

NASA Astrophysics Data System (ADS)

A series of ten radiotracer experiments were conducted in controlled experimental ecosystems (mesocosms) to investigate the behavior of volatile organic compounds (VOC) in seawater. Time-series measurements of the redistribution of 14C-activity within several major pools - dissolved, particulate, intermediate metabolite, and CO 2 - in the ecosystem made possible an evaluation of the rates of processes - volatilization, biodegradation, Sorption and sedimentation - acting to remove VOC from seawater in summer. The behavior of the model 14C-VOC fell into three categories. Aromatic hydrocarbons (benzene, toluene, naphthalene) were subject to both volatilization and biodegradation, with mineralization dominating in summer. Chlorinated C 2-hydrocarbons (tetrachloroethylene) and chlorinated benzenes (chlorobenzene, 1,4-dichlorobenzene, and 1,2,4-trichlorobenzene) were affected only by volatilization and were relatively resistant to biodegradation. Of all the model VOC studied, only aliphatic hydrocarbons (decane and octadecane) were sorbed onto suspended paniculate matter; however, the primary route of loss from the water column appeared to be biodegradation rather than sedimentation. The mesocosm-derived removal rate constants were then applied to estimate summer VOC residence times in Narragansett Bay, Rhode Island of about 1 day for aromatic hydrocarbons, 1 week for the chlorinated VOC and about 1 day for aliphatic hydrocarbons. Residence times in winter might be on the order of 1 week for all VOC.

Wakeham, Stuart G.; Canuel, Elizabeth A.; Doering, Peter H.

1986-06-01

382

Collapsing Aged Culture of the Cyanobacterium Synechococcus elongatus Produces Compound(s) Toxic to Photosynthetic Organisms  

PubMed Central

Phytoplankton mortality allows effective nutrient cycling, and thus plays a pivotal role in driving biogeochemical cycles. A growing body of literature demonstrates the involvement of regulated death programs in the abrupt collapse of phytoplankton populations, and particularly implicates processes that exhibit characteristics of metazoan programmed cell death. Here, we report that the cell-free, extracellular fluid (conditioned medium) of a collapsing aged culture of the cyanobacterium Synechococcus elongatus is toxic to exponentially growing cells of this cyanobacterium, as well as to a large variety of photosynthetic organisms, but not to eubacteria. The toxic effect, which is light-dependent, involves oxidative stress, as suggested by damage alleviation by antioxidants, and the very high sensitivity of a catalase-mutant to the conditioned medium. At relatively high cell densities, S. elongatus cells survived the deleterious effect of conditioned medium in a process that required de novo protein synthesis. Application of conditioned medium from a collapsing culture caused severe pigment bleaching not only in S. elongatus cells, but also resulted in bleaching of pigments in a cell free extract. The latter observation indicates that the elicited damage is a direct effect that does not require an intact cell, and therefore, is mechanistically different from the metazoan-like programmed cell death described for phytoplankton. We suggest that S. elongatus in aged cultures are triggered to produce a toxic compound, and thus, this process may be envisaged as a novel regulated death program. PMID:24959874

Cohen, Assaf; Sendersky, Eleonora; Carmeli, Shmuel; Schwarz, Rakefet

2014-01-01

383

Emission of volatile organic compounds from silage: Compounds, sources, and implications  

NASA Astrophysics Data System (ADS)

Silage, fermented cattle feed, has recently been identified as a significant source of volatile organic compounds (VOCs) to the atmosphere. A small number of studies have measured VOC emission from silage, but not enough is known about the processes involved to accurately quantify emission rates and identify practices that could reduce emissions. Through a literature review, we have focused on identifying the most important compounds emitted from corn silage (the most common type of silage in the US) and the sources of these compounds by quantifying their production and emission potential in silage and describing production pathways. We reviewed measurements of VOC emission from silage and assessed the importance of individual silage VOCs through a quantitative analysis of VOC concentrations within silage. Measurements of VOC emission from silage and VOCs present within silage indicated that alcohols generally make the largest contribution to emission from corn silage, in terms of mass emitted and potential ozone formation. Ethanol is the dominant alcohol in corn silage; excluding acids, it makes up more than half of the mean mass of VOCs present. Acids, primarily acetic acid, may be important when emission is high and all VOCs are nearly depleted by emission. Aldehydes and esters, which are more volatile than acids and alcohols, are important when exposure is short, limiting emission of more abundant but less volatile compounds. Variability in silage VOC concentrations is very high; for most alcohols and acids, tolerance intervals indicate that 25% of silages have concentrations a factor of two away from median values, and possibly much further. This observation suggests that management practices can significantly influence VOC concentrations. Variability also makes prediction of emissions difficult. The most important acids, alcohols, and aldehydes present in silage are probably produced by bacteria (and, in the case of ethanol, yeasts) during fermentation and storage of silage. Aldehydes may also be produced aerobically by spoilage microorganisms through the oxidation of alcohols. Abiotic reactions may be important for production of methanol and esters. Although silage additives appear to affect VOC production in individual studies, bacterial inoculants have not shown a consistent effect on ethanol, and effects on other VOCs have not been studied. Production of acetic acid is understood, and production could be minimized, but a decrease could lead to an increase in other, more volatile and more reactive, VOCs. Chemical additives designed for controlling yeasts and undesirable bacteria show promise for reducing ethanol production in corn silage. More work is needed to understand silage VOC production and emission from silage, including: additional measurements of VOC concentrations or production in silage of all types, and an exploration of the causes of variability; accurate on-farm measurements of VOC emission, including an assessment of the importance of individual ensiling stages and practices that could reduce emission of existing VOCs; and work on understanding the sources of silage VOCs and possible approaches for reducing production.

Hafner, Sasha D.; Howard, Cody; Muck, Richard E.; Franco, Roberta B.; Montes, Felipe; Green, Peter G.; Mitloehner, Frank; Trabue, Steven L.; Rotz, C. Alan

2013-10-01

384

Profiling contents of water-soluble metabolites and mineral nutrients to evaluate the effects of pesticides and organic and chemical fertilizers on tomato fruit quality.  

PubMed

In this study, the contents of water-soluble metabolites and mineral nutrients were measured in tomatoes cultured using organic and chemical fertilizers, with or without pesticides. Mineral nutrients and water-soluble metabolites were determined by inductively coupled plasma-atomic emission spectrometry and (1)H nuclear magnetic resonance spectrometry, respectively, and results were analysed by principal components analysis (PCA). The mineral nutrient and water-soluble metabolite profiles differed between organic and chemical fertilizer applications, which accounted for 88.0% and 55.4%, respectively, of the variation. (1)H-(13)C-hetero-nuclear single quantum coherence experiments identified aliphatic protons that contributed to the discrimination of PCA. Pesticide application had little effect on mineral nutrient content (except Fe and P), but affected the correlation between mineral nutrients and metabolites. Differences in the content of mineral nutrients and water-soluble metabolites resulting from different fertilizer and pesticide applications probably affect tomato quality. PMID:25236242

Watanabe, Masami; Ohta, Yuko; Licang, Sun; Motoyama, Naoki; Kikuchi, Jun

2015-02-15

385

Volatile organic compound emissions from dry mill fuel ethanol production.  

PubMed

Ethanol fuel production is growing rapidly in the rural Midwest, and this growth presents potential environmental impacts. In 2002, the U.S. Environmental Protection Agency (EPA) and the Minnesota Pollution Control Agency (MPCA) entered into enforcement actions with 12 fuel ethanol plants in Minnesota. The enforcement actions uncovered underreported emissions and resulted in consent decrees that required pollution control equipment be installed. A key component of the consent decrees was a requirement to conduct emissions tests for volatile organic compounds (VOCs) with the goal of improving the characterization and control of emissions. The conventional VOC stack test method was thought to underquantify total VOC emissions from ethanol plants. A hybrid test method was also developed that involved quantification of individual VOC species. The resulting database of total and speciated VOC emissions from 10 fuel ethanol plants is relatively small, but it is the most extensive to date and has been used to develop and gauge compliance with permit limits and to estimate health risks in Minnesota. Emissions were highly variable among facilities and emissions units. In addition to the variability, the small number of samples and the presence of many values below detection limits complicate the analysis of the data. To account for these issues, a nested bootstrap procedure on the Kaplan-Meier method was used to calculate means and upper confidence limits. In general, the fermentation scrubbers and fluid bed coolers emitted the largest mass of VOC emissions. Across most facilities and emissions units ethanol was the pollutant emitted at the highest rate. Acetaldehyde, acetic acid, and ethyl acetate were also important emissions from some units. Emissions of total VOCs, ethanol, and some other species appeared to be a function of the beer feed rate, although the relationship was not reliable enough to develop a production rate-based emissions factor. PMID:17912928

Brady, Daniel; Pratt, Gregory C

2007-09-01

386

Peat fires and air quality: volatile organic compounds and particulates.  

PubMed

There are numerous localized peat deposits on the Swan Coastal Plain, an urban and rural bioregion otherwise dominated by wetland ecosystems in southwestern Australia. Hydrological change is significant in the bioregion: urban development encroaches on wetlands, groundwater extraction provides the city population with most of its water, and rainfall declines will not recharge aquifers in the future. The wetland processes which contribute to the formation of these peat deposits have therefore changed and are becoming vulnerable to fire events with residents increasingly exposed to peat smoke. There is an imperative to characterise this peat smoke to determine if exposures are harmful or toxic, and opportunities to do so in this setting arise due to the absence of bushfire smoke which has confounded other international studies. We have measured volatile organic compounds (VOCs) and particulate concentrations from an opportunistic assessment of two peat fires. SUMMA canister grab samples and a portable GCMS were used to determine the VOCs with high 1h benzene concentrations of 16 and 30 ppm v/v. PM10 and PM2.5 particulate data were collected using an Osiris continuous analyser with 24h concentrations recorded at varying time periods (within a 5 months timeframe) ranging from 1h maximums of between 23-37 microgm(-3) for PM10 and 50.5-106 microgm(-3) for PM2.5. While the 24h averages were generally below national air quality standards, elevated 1h concentrations were observed on numerous occasions and on most days. Given the proximity of residential development to many peat deposits, a drying climate and the increased risk of arson in peri-urban environments, the health impacts of exposure to peat smoke need to be determined and if necessary measures developed to prevent exposure (which would include maintaining wetland sediment integrity so as to reduce its vulnerability to fire). PMID:19394676

Blake, D; Hinwood, A L; Horwitz, P

2009-07-01

387

Sources of Volatile Organic Compounds (VOCs) in the UAE  

NASA Astrophysics Data System (ADS)

The gas chromatography-flame ionization detection/mass spectrometry system has been used to identify major volatile organic compounds (VOCs) sources in the UAE (latitude 24.45N; longitude 54.22E). VOCs are emitted from an extensive number of sources in urban environments including fuel production, distribution, and consumption. Transport sources contribute a substantial portion of the VOC burden to the urban atmosphere in developed regions. UAE is located at the edge of the Persian Gulf and is highly affected by emissions from petrochemical industries in neighbouring Saudi Arabia, Qatar, and Iran. VOCs emerging from these industries can be transported to the UAE with jet streams. The analysis of the collected air samples at three locations in Sharjah, UAE during the autumn and winter seasons indicates the presence of more than 100 VOC species. The concentrations of these species vary in magnitudes but the most prominent are: acetylene, ethane, propane, butane, pentane, benzene, and toluene. The possible tracers for various emission sources have also been identified such as 2-methylpentane, 1, 3-butadiene and 2, 2-dimethlybutane for vehicle exhaust, the light hydrocarbons, namely n-butane, trans-2-butene, and n-pentane for gasoline vapor, and n-nonane, n-decane, and n-undecane for diesel vapor and asphalt application processes. As various emission sources are characterized by overlapping VOC species, the ratio of possible VOC tracers are used to quantify the contribution of different sources. Our aim in this paper is to explore and discuss possible impacts of transported emissions on the local VOC emission inventory from various sources for the UAE. This work is partially supported by Office of Development and Alumni Affairs at the American University of Sharjah, U.A.E.

Abbasi, Naveed; Majeed, Tariq; Iqbal, Mazhar; Riemer, Daniel; Apel, Eric; Lootah, Nadia

388

Quantitative determination of volatile organic compounds in indoor dust using gas chromatography-UV spectrometry  

Microsoft Academic Search

A novel technique, gas chromatography-UV spectrometry (GC-UV), was used to quantify volatile organic compounds (VOCs) in settled dust from 389 residences in Sweden. The dust samples were thermally desorbed in an inert atmosphere and evaporated compounds were concentrated by solid phase micro extraction and separated by capillary GC. Eluting compounds were then detected, identified, and quantified using a diode array

Anders Nilsson; Verner Lagesson; Carl-Gustaf Bornehag; Jan Sundell; Christer Tagesson

2005-01-01

389

Chlorinated and brominated persistent organic compounds in biological samples from the environment  

Microsoft Academic Search

Eleven selected biological samples representing different ecosystems, trophic levels, and areas mainly in Sweden have been analyzed for 31 halogenated organic compounds or compound groups. The multiresidue analytical method provides a good opportunity to compare the concentrations of the different compounds in the investigated samples. By the use of ratios of these concentrations, comparisons can be done between species and

Bo Jansson; Renate Andersson; Lillemor Asplund; K. Litzen; Kerstin Nylund; U. Sellstroem; Ulla-Britt Uvemo; Cajsa Wahlberg; Ulla Wideqvist; T. Odsjoe; Mats Olsson

1993-01-01

390

Detection of volatile organic compounds by weight-detectable sensors coated with metal-organic frameworks.  

PubMed

Detection of volatile organic compounds (VOCs) using weight-detectable quartz microbalance and silicon-based microcantilever sensors coated with crystalline metal-organic framework (MOF) thin films is described in this paper. The thin films of two MOFs were grown from COOH-terminated self-assembled monolayers onto the gold electrodes of sensor platforms. The MOF layers worked as the effective concentrators of VOC gases, and the adsorption/desorption processes of the VOCs could be monitored by the frequency changes of weight-detectable sensors. Moreover, the MOF layers provided VOC sensing selectivity to the weight-detectable sensors through the size-selective adsorption of the VOCs within the regulated nanospace of the MOFs. PMID:25175808

Yamagiwa, Hiroki; Sato, Seiko; Fukawa, Tadashi; Ikehara, Tsuyoshi; Maeda, Ryutaro; Mihara, Takashi; Kimura, Mutsumi

2014-01-01

391

Detection of Volatile Organic Compounds by Weight-Detectable Sensors coated with Metal-Organic Frameworks  

NASA Astrophysics Data System (ADS)

Detection of volatile organic compounds (VOCs) using weight-detectable quartz microbalance and silicon-based microcantilever sensors coated with crystalline metal-organic framework (MOF) thin films is described in this paper. The thin films of two MOFs were grown from COOH-terminated self-assembled monolayers onto the gold electrodes of sensor platforms. The MOF layers worked as the effective concentrators of VOC gases, and the adsorption/desorption processes of the VOCs could be monitored by the frequency changes of weight-detectable sensors. Moreover, the MOF layers provided VOC sensing selectivity to the weight-detectable sensors through the size-selective adsorption of the VOCs within the regulated nanospace of the MOFs.

Yamagiwa, Hiroki; Sato, Seiko; Fukawa, Tadashi; Ikehara, Tsuyoshi; Maeda, Ryutaro; Mihara, Takashi; Kimura, Mutsumi

2014-09-01

392

Adsorption of volatile organic compounds in porous metal-organic frameworks functionalized by polyoxometalates  

NASA Astrophysics Data System (ADS)

The functionalization of porous metal-organic frameworks (Cu 3( BTC) 2) was achieved by incorporating Keggin-type polyoxometalates (POMs), and further optimized via alkali metal ion-exchange. In addition to thermal gravimetric analysis, IR, single-crystal X-ray diffraction, and powder X-ray diffraction, the adsorption properties were characterized by N 2 and volatile organic compounds (VOCs) adsorption measurements, including short-chain alcohols ( C<4), cyclohexane, benzene, and toluene. The adsorption enthalpies estimated by the modified Clausius-Clapeyron equation provided insight into the impact of POMs and alkali metal cations on the adsorption of VOCs. The introduction of POMs not only improved the stability, but also brought the increase of adsorption capacity by strengthening the interaction with gas molecules. Furthermore, the exchanged alkali metal cations acted as active sites to interact with adsorbates and enhanced the adsorption of VOCs.

Ma, Feng-Ji; Liu, Shu-Xia; Liang, Da-Dong; Ren, Guo-Jian; Wei, Feng; Chen, Ya-Guang; Su, Zhong-Min

2011-11-01

393

Detection of Volatile Organic Compounds by Weight-Detectable Sensors coated with Metal-Organic Frameworks  

PubMed Central

Detection of volatile organic compounds (VOCs) using weight-detectable quartz microbalance and silicon-based microcantilever sensors coated with crystalline metal-organic framework (MOF) thin films is described in this paper. The thin films of two MOFs were grown from COOH-terminated self-assembled monolayers onto the gold electrodes of sensor platforms. The MOF layers worked as the effective concentrators of VOC gases, and the adsorption/desorption processes of the VOCs could be monitored by the frequency changes of weight-detectable sensors. Moreover, the MOF layers provided VOC sensing selectivity to the weight-detectable sensors through the size-selective adsorption of the VOCs within the regulated nanospace of the MOFs. PMID:25175808

Yamagiwa, Hiroki; Sato, Seiko; Fukawa, Tadashi; Ikehara, Tsuyoshi; Maeda, Ryutaro; Mihara, Takashi; Kimura, Mutsumi

2014-01-01

394

Rejection of organic micropollutants (disinfection by-products, endocrine disrupting compounds, and pharmaceutically active compounds) by NF\\/RO membranes  

Microsoft Academic Search

The growing demand on water resources has increased interest in wastewater reclamation for potable reuse, in which rejection of organic micropollutants such as disinfection by-products (DBPs), endocrine disrupting compounds (EDCs), and pharmaceutically active compounds (PhACs) is of great concern. The objective of this study was to investigate the rejection of DBPs, EDCs, and PhACs by nanofiltration (NF) and reverse osmosis

Katsuki Kimura; Gary Amy; Jörg E. Drewes; Thomas Heberer; Tae-Uk Kim; Yoshimasa Watanabe

2003-01-01

395

Information-retrieval facilities for identifying organic compounds from infrared spectra  

SciTech Connect

The authors consider the features of an IRS designed for an ES-1010 microcomputer and intended for identifying organic compounds from their IR spectra, and in particular, trace organic compounds in a natural waters and effluents after isolation in the pure state.

Antipova-Karataeva, I.I.; Rykova, E.A.; Kazanova, N.N.

1986-07-10

396

SOIL SORPTION OF VOLATILE AND SEMIVOLATILE ORGANIC COMPOUNDS IN A MIXTURE  

EPA Science Inventory

Studies were conducted to evaluate lipophilicity as a predictor of sorption for a mixture of organic compounds with high vapor pressures commonly present at hazardous waste sites. orption partition coefficients (Kp) for the mixture of 16 volatile and semivolatile organic compound...

397

Characterization of microbial species in a regenerative bio-filter system for volatile organic compound removal  

Microsoft Academic Search

Effective removal of volatile organic compounds is critical for indoor air quality control. The performance of traditional technologies of volatile organic compound removal is limited by inadequate selection of filter media, poor airflow management inside the cleaning devices, insufficient catalytic reaction surface area, and poor distribution of UV light irradiation. In comparison, the relatively new regenerative air filtration systems use

Wen-Hsuan Huang; Zhiqiang Wang; Geetika Choudhary; Beverly Guo; Jianshun Zhang; Dacheng Ren

2012-01-01

398

The effect of concentration polarization on the separation of volatile organic compounds from water by pervaporation  

Microsoft Academic Search

Concentration polarization dominates the separation of dissolved volatile organic compounds from water by pervaporation. This is particularly true with hydrophobic organics, such as toluene and trichloroethylene, for which concentration polarization is severe even in highly turbulent membrane modules. With these compounds, measured separation factors can be 10 to 20% of the intrinsic separation factors in the absence of concentration polarization.

R. W. Baker; J. G. Wijmans; A. L. Athayde; R. Daniels; J. H. Ly; M. Le

1997-01-01

399

40 CFR 60.112 - Standard for volatile organic compounds (VOC).  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Standard for volatile organic compounds (VOC). 60.112 Section 60.112 Protection of Environment...May 19, 1978 § 60.112 Standard for volatile organic compounds (VOC). (a) The owner or operator of any storage...

2010-07-01

400

40 CFR 60.542a - Alternate standard for volatile organic compounds.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Alternate standard for volatile organic compounds. 60.542a Section 60.542a Protection of Environment...Industry § 60.542a Alternate standard for volatile organic compounds. (a) On and after the date on which the...

2010-07-01

401

40 CFR 60.312 - Standard for volatile organic compounds (VOC).  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Standard for volatile organic compounds (VOC). 60.312 Section 60.312 Protection of Environment...Metal Furniture § 60.312 Standard for volatile organic compounds (VOC). (a) On and after the date on which the...

2011-07-01

402

40 CFR 60.112 - Standard for volatile organic compounds (VOC).  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Standard for volatile organic compounds (VOC). 60.112 Section 60.112 Protection of Environment...May 19, 1978 § 60.112 Standard for volatile organic compounds (VOC). (a) The owner or operator of any storage...

2011-07-01

403

40 CFR 60.312 - Standard for volatile organic compounds (VOC).  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Standard for volatile organic compounds (VOC). 60.312 Section 60.312 Protection of Environment...Metal Furniture § 60.312 Standard for volatile organic compounds (VOC). (a) On and after the date on which the...

2010-07-01

404

40 CFR 60.542a - Alternate standard for volatile organic compounds.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Alternate standard for volatile organic compounds. 60.542a Section 60.542a Protection of Environment...Industry § 60.542a Alternate standard for volatile organic compounds. (a) On and after the date on which the...

2011-07-01

405

Effects of predator cues on pesticide toxicity: toward an understanding of the mechanism of the interaction.  

PubMed

Pesticide toxicity may be modified by a number of co-occurring environmental and ecological stressors. Coexposure to predator cues has been shown to potentiate and/or synergize toxicity of pesticides. However, the mechanisms behind these interactions are not well understood. Here we examine the effects of fish predator (bluegill, Lepomis macrochirus) cues on toxicity of five different pesticides to the freshwater cladoceran, Ceriodaphnia dubia. The purpose for examining patterns among pesticides was to test the idea that the mechanism of the interaction could be explained by a general stress response; that is, the interaction patterns would be similar regardless of the pesticide's mechanism of action [MOA]). Acute 96-h concentration-response experiments were conducted for pesticides with and without fish cues. Predator cues influenced the toxicity of pesticides and the interaction patterns varied among pesticides. Fipronil exhibited a synergistic interaction, while predator cues interacted antagonistically for bifenthrin and thiacloprid. Other compounds previously reported to potentiate toxicity (malathion) were found to act additively. The results demonstrate that factors such as pesticide bioavailability, K(OC) , and exposure concentration may be important for predicting the occurrence of these interactions and that patterns were not consistent among pesticides varying in MOA. Predator stress is an important component for structuring communities and ecosystem processes. Fully understanding how this process may interact with organic contaminants may best be achieved by examination at toxicokinetic and toxicodynamic scales. PMID:21560149

Qin, Guangqiu; Presley, Steven M; Anderson, Todd A; Gao, Weimin; Maul, Jonathan D

2011-08-01

406

METABOLISM OF PESTICIDES BY PLANTS AND PROKARYOTES  

Technology Transfer Automated Retrieval System (TEKTRAN)

The metabolism of pesticides by plants is a key factor in the susceptibility and tolerance of a species to a given pesticide, whereas metabolism by prokaryotes is often a key determinant in the environmental fate of that pesticide. Thus, understanding pesticide metabolism in both groups of organisms...

407

Distributions of pesticides and organic contaminants between water and suspended sediment, San Francisco Bay, California  

SciTech Connect

Suspended-sediment and water samples were collected from San Francisco Bay in 1991 during low river discharge and after spring rains. All samples were analyzed for organophosphate, carbamate, and organochlorine pesticides; petroleum hydrocarbons; biomarkers; and polynuclear aromatic hydrocarbons. The objective were to determine the concentrations of these contaminants in water and suspended sediment during two different hydrologic conditions and to determine partition coefficients of the contaminants between water and sediment. Concentrations of hydrophobic contaminants, such as polynuclear aromatic hydrocarbons, varied with location of sample collection, riverine discharge, and tidal cycle. Concentrations of hydrophobic contaminants in suspended sediments were highest during low river discharge but became diluted as agricultural soils entered the bay after spring rains. Polynuclear aromatic hydrocarbons defined as dissolved in the water column were not detected. The concentrations sorbed on suspended sediments were variable and were dependent on sediment transport patterns in the bay. In contrast, the relatively hydrophilic organophosphate pesticides, such as chlorpyrifos and diazinon, had a ore uniform concentration in suspended sediment. These pesticides were detected only after spring rains. Most of the measured diazinon, at least 98% for all samples, was in the dissolved phase. Measured partition coefficients for diazinon generally were uniform, which suggest that suspended-sediment concentrations were close to equilibrium with dissolved concentrations. The concentration of diazinon sorbed to suspended sediments, at any given sampling site, was driven primarily by the more abundant solution concentration. The concentrations of diazinon sorbed to suspended sediments, therefore, were independent of the patterns of sediment movement. 27 refs., 5 figs., 4 tabs.

Domagalski, J.L.; Kuivila, K.M. (Department of the Interior, Sacramento, CA (United States))

1993-12-01

408

Chemical process for the catalytic oxidation of formaldehyde and other organic compounds  

SciTech Connect

The invention discusses a chemical process for the catalytic oxidation of formaldehyde and other organic compounds contained in a dilute aqueous solution, particularly waste water. The inventive feature resides in the use of a cobalt catalyst to increase the rate of oxidation of the organic compounds when hypochlorous acid is the oxidant. The latter may be provided by a chlorine compound, such as sodium hypochlorite, calcium hypochlorite or chlorine gas dissolved in water.

Murphy, A.P.

1991-01-01

409

[Influence of exogenous sulfur-containing compounds on the exchange fluxes of volatile organic sulfur compounds].  

PubMed

The influences of cysteine, sodium sulfide (Na2S) and sodium sulfate (Na2SO4) on the soil-air exchange fluxes of volatile organic sulfur compounds (VOSCs), including carbonyl sulfide (COS), dimethyl sulfide (DMS), carbon disulfide (CS2) and dimethyl disulfide (DMDS), were studied employing static chamber enclosure followed by laboratory determination using an Entech 7100 preconcentrator coupled with an Agilent 5973 GC-MSD. The results showed that after the addition of cysteine, the soil for the exchange fluxes of COS and CS2 shifted to be the source from sink and the emissions of DMS and DMDS increased significant. The emission amount of DMS and CS2 accounted for 89.2% to the total VOSCs after the addition of cysteine, implying that cysteine is an important precursor for DMS and CS2 in the soil. The amount of DMDS accounted for 93.2% to the total sulfur from the soil after addition of Na2S, indicating that Na2S is a key precursor for DMDS. No significant difference of VOSCs fluxes was found between the controlled soil and the soil with addition of Na2SO4, suggesting Na2SO4 was not the direct precursor for VOSCs in soil. VOSCs exchange rates reached the maximum at 6 to 8 days after addition of cysteine. As for addition of Na2S, the maximal emission rates of different VOSCs appeared at different dates, and the dates differed significantly from those after addition of cysteine, implying that the formation process of VOSCs from the soil with addition of Na2S was more complex and different from the soil with addition of cysteine. PMID:22619943

Yi, Zhi-Gang; Wang, Xin-Ming

2011-08-01

410

Enhancement effect of water associated with natural organic matter (NOM) on organic compound–NOM interactions: A case study with carbamazepine  

Microsoft Academic Search

Natural organic matter (NOM) in soils and sediments is recognized to strongly affect environmental distributions of organic compounds. Water associated with NOM may have a significant impact on NOM–organic compound interactions. The objectives of this research were (1) to determine the effect of hydration of a model NOM sorbent on interactions with a probe organic compound, carbamazepine (CBZ), and (2)

Mikhail Borisover; Maggie Sela; Benny Chefetz

2011-01-01

411

Nano porous silicon microcavity sensor for determination organic solvents and pesticide in water  

NASA Astrophysics Data System (ADS)

In this paper we present a sensing method using nano-porous silicon microcavity sensor, which was developed in order to obtain simultaneous determination of two volatile substances with different solvent concentrations as well as very low pesticide concentration in water. The temperature of the solution and the velocity of the air stream flowing through the solution have been used to control the response of the sensor for different solvent solutions. We study the dependence of the cavity-resonant wavelength shift on solvent concentration, velocity of the airflow and solution temperature. The wavelength shift depends linearly on concentration and increases with solution temperature and velocity of the airflow. The dependence of the wavelength shift on the solution temperature in the measurement contains properties of the temperature dependence of the solvent vapor pressure, which characterizes each solvent. As a result, the dependence of the wavelength shift on the solution temperature discriminates between solutions of ethanol and acetone with different concentrations. This suggests a possibility for the simultaneous determination of the volatile substances and their concentrations. On the other hand, this method is able to detect the presence of atrazine pesticide by the shift of the resonant wavelength, with good sensitivity (0.3 nm pg?1 ml) and limit of detection (LOD) (0.8–1.4 pg ml?1), that we tested for concentrations in the range from 2.15 to 21.5 pg ml?1, which is the range useful for monitoring acceptable water for human consumption.

Pham, Van Hoi; Van Nguyen, Thuy; Nguyen, The Anh; Pham, Van Dai; Bui, Huy

2014-12-01

412

The composition of the primitive atmosphere and the synthesis of organic compounds on the early Earth  

NASA Technical Reports Server (NTRS)

The generally accepted theory for the origin of life on the Earth requires that a large variety of organic compounds be present to form the first living organisms and to provide the energy sources for primitive life either directly or through various fermentation reactions. This can provide a strong constraint on discussions of the formation of the Earth and on the composition of the primitive atmosphere. In order for substantial amounts of organic compounds to have been present on the prebiological Earth, certain conditions must have existed. There is a large body of literature on the prebiotic synthesis of organic compounds in various postulated atmospheres. In this mixture of abiotically synthesized organic compounds, the amino acids are of special interest since they are utilized by modern organisms to synthesize structural materials and a large array of catalytic peptides.

Bada, J. L.; Miller, S. L.

1985-01-01

413

Photocatalytic oxidation of volatile organic compounds using fluorescent visible light.  

PubMed

Photocatalytic oxidation (PCO) of volatile organic compounds (VOCs) is a highly attractive alternative technology for purification and deodorization of indoor air. The main objectives of this study were to demonstrate that a common fluorescent visible light (FVL) lamp can be used to effectively remove by PCO low concentrations of VOCs from slightly contaminated air and to provide some fundamental and technical details on the process. The target VOC was n-butanol, which is a standard reference odorant. Its PCO was studied under a long residence time in a 3.7-L cylindrical reactor with commercial titanium dioxide (TiO2) as the reference photocatalyst and using mostly FVL for illumination. For comparison only, a UV (black) light lamp was used. The gas-phase products were detected and quantified online by gas chromatography (GC). The effects of reactor residence time, of inlet concentration, and of the relative light intensity on the efficiency of the process were also evaluated. At a high n-butanol concentration (0.1 vol %), butanal and propanal were identified as the intermediate products of the process; ethanal appeared when the initial concentration was < or = 850 ppm(v). This indicates that PCO leading to CO2 and H2O is relatively slow and proceeds in a stepwise manner. Although the efficiency of the process with an FVL lamp was significantly lower than when using a UV black light, complete PCO of low concentrations was achieved for 100 ppm(v). In a search for a material with photoactivation extended to higher wavelengths or increased photoactivity, several samples of transition metal- or silver ion-doped (2 atomic %) TiO2 as well as SrTi(1-x-)Fe(x)O3 (x = 0.1 and 0.15) perovskites were included in the study. None of these materials was more active than pure TiO2. The results of this study open new horizons in the area of in door air quality (IAQ) control. PMID:12139349

Chapuis, Yannick; Klvana, Danilo; Guy, Christophe; Kirchnerova, Jitka

2002-07-01

414

Volatile Organic Compound Investigation Results, 300 Area, Hanford Site, Washington  

SciTech Connect

Unexpectedly high concentrations of volatile organic compounds (VOC) were discovered while drilling in the unconfined aquifer beneath the Hanford Site’s 300 Area during 2006. The discovery involved an interval of relatively finer-grained sediment within the unconfined aquifer, an interval that is not sampled by routine groundwater monitoring. Although VOC contamination in the unconfined aquifer has been identified and monitored, the concentrations of newly discovered contamination are much higher than encountered previously, with some new results significantly higher than the drinking water standards. The primary contaminant is trichloroethene, with lesser amounts of tetrachloroethene. Both chemicals were used extensively as degreasing agents during the fuels fabrication process. A biological degradation product of these chemicals, 1,2-dichloroethene, was also detected. To further define the nature and extent of this contamination, additional characterization drilling was undertaken during 2007. Four locations were drilled to supplement the information obtained at four locations drilled during the earlier investigation in 2006. The results of the combined drilling indicate that the newly discovered contamination is limited to a relatively finer-grained interval of Ringold Formation sediment within the unconfined aquifer. The extent of this contamination appears to be the area immediately east and south of the former South Process Pond. Samples collected from the finer-grained sediment at locations along the shoreline confirm the presence of the contamination near the groundwater/river interface. Contamination was not detected in river water that flows over the area where the river channel potentially incises the finer-grained interval of aquifer sediment. The source for this contamination is not readily apparent. A search of historical documents and the Hanford Waste Information Data System did not provide definitive clues as to waste disposal operations and/or spills that might have resulted in groundwater contamination in this sediment, although several relatively small accidental releases of VOCs have occurred in the past in the northern portion of the 300 Area. It is likely that large quantities of degreasing solutions were disposed to the North and South Process Ponds during the 1950s and 1960s, and that evidence for them in the upper portion of the unconfined aquifer has been removed because of groundwater movement through the much more transmissive sediment. Also, investigations to date have revealed no evidence to suggest that a dense, non-aqueous phase liquid remains undetected in the subsurface. Potential pathways for contamination to migrate from this finer-grained sediment include groundwater movement through the interval to offshore locations in the Columbia River channel, dispersion out of the finer-grained interval into the overlying transmissive sediment (again, with transport to the riverbed), and potential future withdrawal via water supply wells.

Peterson, Robert E.; Williams, Bruce A.; Smith, Ronald M.

2008-07-07

415

Airborne flux measurements of biogenic volatile organic compounds over California  

NASA Astrophysics Data System (ADS)

Biogenic Volatile Organic Compound (BVOC) fluxes were measured onboard the CIRPAS Twin Otter aircraft as part of the California Airborne BVOC Emission Research in Natural Ecosystem Transects (CABERNET) campaign during June 2011. The airborne virtual disjunct eddy covariance (AvDEC) approach used measurements from a PTR-MS and a wind radome probe to directly determine fluxes of isoprene, MVK + MAC, methanol, monoterpenes, and MBO over ∼10 000 km of flight paths focusing on areas of California predicted to have the largest emissions of isoprene. The Fast Fourier Transform (FFT) approach was used to calculate fluxes over long transects of more than 15 km, most commonly between 50 and 150 km. The Continuous Wavelet Transformation (CWT) approach was used over the same transects to also calculate "instantaneous" fluxes with localization of both frequency and time independent of non-stationarities. Vertical flux divergence of isoprene is expected due to its relatively short lifetime and was measured directly using "racetrack" profiles at multiple altitudes. It was found to be linear and in the range 5% to 30% depending on the ratio of aircraft altitude to PBL height (z / zi). Fluxes were generally measured by flying consistently at 400 ± 50 m (a.g.l.) altitude, and extrapolated to the surface according to the determined flux divergence. The wavelet-derived surface fluxes of isoprene averaged to 2 km spatial resolution showed good correspondence to Basal Emission Factor (BEF) landcover datasets used to drive biogenic VOC (BVOC) emission models. The surface flux of isoprene was close to zero over Central Valley crops and desert shrublands, but was very high (up to 15 mg m-2 h-1) above oak woodlands, with clear dependence of emissions on temperature and oak density. Isoprene concentrations of up to 8 ppb were observed at aircraft height on the hottest days and over the dominant source regions. While isoprene emissions from agricultural crop regions, shrublands, and coniferous forests were extremely low, high concentrations of methanol and monoterpenes were found above some of these regions. These observations demonstrate the ability to measure fluxes from specific sources by eddy covariance from an aircraft, and suggest the utility of measurements using fast response chemical sensors to constrain emission inventories and map out source distributions for a much broader array of trace gases than was observed in this study. This paper reports the first regional direct eddy covariance fluxes of isoprene. The emissions of VOCs measured from aircraft with 2 km spatial resolution can quantify the distribution of major sources providing the observations required for testing statewide emission inventories of these important trace gases. These measurements will be used in a future study to assess BVOC emission models and their driving variable datasets.

Misztal, P. K.; Karl, T.; Weber, R.; Jonsson, H. H.; Guenther, A. B.; Goldstein, A. H.

2014-03-01

416

The Separation and Identification of Two Unknown Solid Organic Compounds: An Experiment for the Sophomore Organic Chemistry Laboratory  

ERIC Educational Resources Information Center

Segregation and recognition of two unfamiliar concrete organic compounds are achieved through microscale flash chromatography and spectroscopy plus melting point verifications respectively. This inexpensive and harmless microscale experiment for sophomore students ensures exercise in chromatographic and spectroscopic methods.

Feist, Patty L.

2004-01-01

417

INFLUENCE OF SURFACTANTS OF MICROBIAL DEGRADATION OF ORGANIC COMPOUNDS  

EPA Science Inventory

Surfactants have the ability to increase aqueous concentrations o poorly soluble compounds and interfacial areas between immiscible fluids, thus potentially improving the accessibility of these substrates to microorganisms. owever, both enhancements and inhibitions of biodegradat...

418

INFLUENCE OF SURFACTANTS ON MICROBIAL DEGRADATION OF ORGANIC COMPOUNDS  

EPA Science Inventory

Surfactants have the ability to increase aqueous concentrations of poorly soluble compounds and interfacial areas between immiscible fluids, thus potentially improving the accessibility of these substrates to microorganisms. However, both enhancements and inhibitions of biodegrad...

419

Methods and systems for chemoautotrophic production of organic compounds  

DOEpatents

The present disclosure identifies pathways, mechanisms, systems and methods to confer chemoautotrophic production of carbon-based products of interest, such as sugars, alcohols, chemicals, amino acids, polymers, fatty acids and their derivatives, hydrocarbons, isoprenoids, and intermediates thereof, in organisms such that these organisms efficiently convert inorganic carbon to organic carbon-based products of interest using inorganic energy, such as formate, and in particular the use of organisms for the commercial production of various carbon-based products of interest.

Fischer, Curt R.; Che, Austin J.; Shetty, Reshma P.; Kelly, Jason R.

2013-01-08

420

Abiotic emissions of methane and reduced organic compounds from organic matter  

NASA Astrophysics Data System (ADS)

Recent laboratory studies show that the important greenhouse gas methane, but also other reduced atmospheric trace gases, can be emitted by abiotic processes from organic matter, such as plants, pure organic compounds and soils. It is very difficult to distinguish abiotic from biotic emissions in field studies, but in laboratory experiments this is easier because it is possible to carefully prepare/sterilize samples, or to control external parameters. For example, the abiotic emissions always show a strong increase with temperature when temperatures are increased to 70C or higher, well above the temperature optimum for bacterial activity. UV radiation has also been clearly shown to lead to emission of methane and other reduced gases from organic matter. Interesting information on the production mechanism has been obtained from isotope studies, both at natural abundance and with isotope labeling. For example, the methoxyl groups of pectin were clearly identified to produce methane. However, analysis of the isotopic composition of methane from natural samples clearly indicates that there must be other molecular mechanisms that lead to methane production. Abiotic methane generation could be a ubiquitous process that occurs naturally at low rates from many different sources.

Roeckmann, T.; Keppler, F.; Vigano, I.; Derendorp, L.; Holzinger, R.

2012-12-01

421

Simultaneous removal of multiple pesticides from water: effect of organically modified clays as coagulant aid and adsorbent in coagulation-flocculation process.  

PubMed

Contamination of drinking water sources with agrochemical residues became a major concern in the twenty-first century. Coagulation-flocculation is the most widely used water-treatment process, but the efficiency to remove pesticides and other organic pollutants are limited compared to adsorption process. Thus, simultaneous action of adsorption on normal bentonite or organo-modified montmorillonite clays [modified with octadecylamine (ODA-M) and octadecylamine + amino-propyltriethoxysilane (ODAAPS-M)] followed by coagulation-flocculation by alum and poly aluminium chloride has been evaluated for removal of 10 different pesticides, namely atrazine, lindane, metribuzin, aldrin, chlorpyriphos, pendimethalin, alpha-endosulphan, beta-endosulphan, p,p'-DDT, cypermethrin and two of its metabolites, endosulphan sulphate and p,p'-DDE, from water. The coagulation without integration of adsorption was less effective (removal % varies from 12 to 49) than the adsorption-coagulation integrated system (removal % varies from 71 to 100). Further, coagulation integrated with adsorption was more effective when organically modified montmorillonite was used as adsorbent compared to normal bentonite. The removal efficiency of organic clay depends upon the concentration of pesticides, doses of clay minerals, and efficiency was more for ODAAPS-M as compared to ODA-M. The combination of ODAAPS-M-clay with coagulants was also used efficiently for the removal of pesticides from natural and fortified natural water collected and the results exhibit the usefulness of this remediation technique for application in water decontamination and in treatment of industrial and agricultural waste waters. PMID:25145219

Shabeer, T P Ahammed; Saha, Ajoy; Gajbhiye, V T; Gupta, Suman; Manjaiah, K M; Varghese, Eldho

2014-01-01

422

Separation of volatile organic compounds by pervaporation for a binary compound combination: Trichloroethylene and 1,1,1-trichloroethane  

SciTech Connect

This study evaluates the behavior of sweeping air pervaporation when used to separate trichloroethylene (TCE) and 1,1,1-trichloroethane (TCEthane) from wastewater. Selectivity and membrane preference are studied. Models for binary compounds are studied to evaluate the extent of cross influence on TCE flux due to the presence of another volatile organic compound, TCEthane. Using the models, the integral dry diffusion coefficient for TCEthane is evaluated. Results indicate that the membrane exhibits a preference for TCE over TCEthane. However, the values of the diffusion rates are found to be comparable. Selectivity values are found to be independent of the air flow rate but dependent on the relative concentration of the compounds in the feed solution. It is found that, due to the presence of TCEthane, the flux of TCE decreased. Further, it is found that the ratio of the integral dry diffusion coefficients of the compounds is inversely proportional to the ratio of their molecular weights.

Visvanathan, C.; Basu, B. [Asian Inst. of Tech., Bangkok (Thailand). Environmental Engineering Program; Mora, J.C. [Inst. National Polytechnique de Toulouse (France)

1995-11-01

423

Volatile organic compounds produced during irradiation of mail.  

PubMed

In 2001, Bacillus anthracis spores were delivered through the United States postal system in a series of bioterrorist acts. Controls proposed for this threat included sanitization with high-energy electrons. Solid phase microextraction was used with gas chromatography/mass spectrometry for field sampling and analysis of volatile compounds apparently produced from polymeric materials such as cellulose and plastics, immediately following processing of mail at a commercial irradiation facility. Solid phase microextraction and direct sampling of air into a cryogenically cooled temperature programmable inlet were used in the laboratory for gas chromatography/mass spectrometry analysis of air in contact with irradiated mail, envelopes only (packaged identically to mail), and air inside irradiated plastic mail packaging bags (with neither mail nor envelopes). Irradiated mail or envelope systems produced hydrocarbons such as propane, butane, pentane, hexane, heptane, methylpentanes, and benzene; and oxygen-containing compounds such as acetaldehyde, acrolein, propionaldehyde, furan, 2-methylfuran, methanol, acetone, 2-butanone, and ethanol. In addition to hydrocarbons, methyl and ethyl nitrate were detected in irradiated bags that contained only air, suggesting reactive nitrogen species formed from air irradiation reacted with hydroxy-containing compounds to give nitro esters. The similarities of volatile compounds in irradiated systems containing paper to those observed by researchers studying cellulose pyrolysis suggests common depolymerization and degradation mechanisms in each case. These similarities should guide additional work to examine irradiated mail for chemical compounds not detectable by methods used here. PMID:12688843

Smith, Philip A; Sheely, Michael V; Hakspiel, Shelly J; Miller, Stephen

2003-01-01