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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

Effects of pesticides and related organic compounds in the sea  

NASA Astrophysics Data System (ADS)

The majority of organic chemicals identified so far in the sea are pesticides and products of technical use; most contain chlorine. Only a limited amount of the actual pollutant load is detectable because few data for “unconventional ” pollutants are available. In view of the considerable structural variety of the large number of chemicals produced, there is a need for prediction measurements of bioconcentration and toxic effects. Physico-chemical data may be used for predicting bioconcentration and life-cycle toxicity tests for the estimation of safe levels. The degree of biomagnification via food chains increases with half lives of the pollutants. When comparing pollutant concentrations with toxicological data it becomes apparent that estuaries and coastal areas deserve special concern, whereas pollutant levels of open ocean waters are unlikely to endanger marine life at present.

Ernst, W.

1980-03-01

3

Organochlorine Pesticide Compounds in Organisms from the Bay of Bengal  

NASA Astrophysics Data System (ADS)

Zooplankton and bottom-feeding fish (four species) from the coastal Bay of Bengal were analysed for residues of DDT, DDD, DDE and aldrin. Concentrations of t-DDT (DDT+DDD+DDE) ranging from 1·31 to 115·90 ng g -1 wet weight in different fish tissues and 4·00 to 1587·76 ng g -1 wet weight in zooplankton were found. Aldrin levels were of the order of 0·32-4·23 ng g -1 in the fish tissues and 'not detected' to 0·78 ng g -1 in zooplankton. The concentration levels are discussed in relation to the distribution of the compounds in different fish tissues, differences in the proportion of DDT and its metabolites DDE and DDD in the various organisms and the possible influence of suspended particulate matter on the availability of DDT residues to organisms in the water column.

Shailaja, M. S.; Singbal, S. Y. S.

1994-09-01

4

Applicability of polar organic compound integrative samplers for monitoring pesticides in groundwater.  

PubMed

Polar organic chemical integrative samplers (POCISs) for the monitoring of polar pesticides in groundwater were tested on two sites in order to evaluate their applicability by comparison with the spot-sampling approach. This preliminary study shows that, as in surface water, POCIS is a useful tool, especially for the screening of substances at low concentration levels that are not detected by laboratory analysis of spot samples. For quantitative results, a rough estimation is obtained. The challenge is now to define the required water-flow conditions for a relevant quantification of pesticides in groundwater and to establish more representative sampling rates for groundwater. PMID:23370850

Berho, Catherine; Togola, Anne; Coureau, Charlotte; Ghestem, Jean-Philippe; Amalric, Laurence

2013-01-31

5

Organic Compounds in the Environment Turfgrass Thatch Effects on Pesticide Leaching: A Laboratory and Modeling Study  

Microsoft Academic Search

or alternately, two-domain flow phenomena within the media. Regulatory agencies and private consultants of- Process-based models are frequently used to assess the water qual- tentimes use linear equilibrium-based models (LEM) ity impacts of turfgrass management emanating from proposed or to assess the effect of turfgrass management practices on existing golf courses. Thatch complicates the prediction of pesticide transport because surface-applied

S. Raturi; M. J. Carroll; R. L. Hill

6

Pesticidal composition to noxious organisms  

US Patent & Trademark Office Database

A pesticidal composition to noxious organisms which comprises a diarylalkane and an active component effective for killing or repelling noxious organisms and the diarylalkane is at least one member selected from the group consisting of butyl diphenylmethane, butyl-1,1-diphenylethane and butyl-1,2-diphenylethane. The used diarylalkane has a high dissolving power to the effective component, a high boiling point and a high flash point with low unpleasant smell and does not deteriorate the effective component in the pesticidal composition.

Sugisawa; Kunio (Yokohama, JP); Togami; Yasuo (Kisarazu, JP); Shouko; Toshikatsu (Kawasaki, JP)

1999-02-02

7

Nitrate, volatile organic compounds, and pesticides in ground water--a summary of selected studies from New Jersey and Long Island, New York  

USGS Publications Warehouse

This report describes the ground-water systems in the unconsolidated sand and gravel aquifers of the Coastal Plain of New Jersey and Long Island and in the fractured bedrock and valley-fill aquifers of northern New Jersey; summarizes current knowledge about the occurrence and distribution of nitrate, volatile organic compounds (VOCs), and pesticides in these systems; and explains why some ground-water systems are more vulnerable to comtamination than others. Although the vulnerability of ground water to contamination from the land surface is influenced by many factors, the degree of aquifer confinement, the depth of the well, and the surrounding land use are key factors. Unconfined aquifers generally are much more vulnerable to contamination than confined aquifers. For a well in a confined aquifer, the farther the well is from the unconfined area, the less vulnerable it is to contamination. Generally, the deeper the well, the less vulnerable it is to contamination. Finally, because human activities greatly affect the quality of water that recharges an aquifer, the amount and type of land use in the area that contributes water to the well is a key factor in determining vulnerability. Nitrate contamination of ground water typically occurs in agricultural and residential areas, especially where the aquifer is very permeable and unconfined and nitrogen-fertilizer use is high. In New Jersey and on Long Island, concentrations of nitrate exceed the U.S. Environmental Protection Agency Maximum Contaminant Level (MCL) more often than those of VOCs or pesticides. Nitrate contamination generally is associated with nonpoint sources. VOC contamination of ground water occurs primarily in urban areas, especially in mixed urban and industrial areas where chemicals are used. In general, VOC concentrations are low and do not exceed MCLs. High concentrations of VOCs generally are associated with point sources. Pesticide contamination of ground water occurs in some agricultural and residential areas, where the aquifer is very permeable and unconfined, and where the chemicals are used. Concentrations of pesticides in New Jersey and on Long Island generally are low; in agricultural areas of Long Island, however, some have been found to exceed MCLs. Pesticide contamination generally is associated with nonpoint sources.

Clawges, Rick M.; Stackelberg, Paul E.; Ayers, Mark A.; Vowinkel, Eric F.

1999-01-01

8

Pesticide Effects on Nontarget Organisms1  

Microsoft Academic Search

This guide addresses the effects of various types of pesticides on nontarget organisms, including natural enemies and beneficial organisms such as honey bees, wildlife, fish, and nontarget plants. Pesticides are an integral part of agriculture and Florida's climate fosters an environment conducive to major pest outbreaks throughout the year. Our environment also is favorable for the development and presence of

Frederick M. Fishel

9

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

10

Methods for determination of toxic organic compounds in air  

SciTech Connect

This paper provides environmental regulatory agencies, industry, and other interested parties with specific, standardized sampling and analysis procedures for toxic organic compounds in air. Compounds include Volatile Organic Compounds, Organochlorine Pesticides and PCBs, Aldehydes and Ketones, Phosgene, N-Nitrosodimethylamine, Phenol and Methylphenols (Cresols), Polychlorinated Dibenzo-p-Dioxins (PCDDs), Formaldehyde, Non-Methane Organic Compounds (NMOCs) and Polynuclear Aromatic Hydrocarbons (PAHs).

Winberry, W.T. Jr.

1990-01-01

11

Semivolatile organic compounds in indoor environments  

Microsoft Academic Search

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

Charles J. Weschler; William W. Nazaroff

2008-01-01

12

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

13

40 CFR 180.1127 - Biochemical pesticide plant floral volatile attractant compounds: cinnamaldehyde, cinnamyl...  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Biochemical pesticide plant floral volatile attractant compounds... § 180.1127 Biochemical pesticide plant floral volatile attractant compounds... Residues of the biochemical pesticide plant floral volatile attractant...

2011-07-01

14

40 CFR 180.1127 - Biochemical pesticide plant floral volatile attractant compounds: cinnamaldehyde, cinnamyl...  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Biochemical pesticide plant floral volatile attractant compounds... § 180.1127 Biochemical pesticide plant floral volatile attractant compounds... Residues of the biochemical pesticide plant floral volatile attractant...

2012-07-01

15

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

National Technical Information Service (NTIS)

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 occur...

A. C. Gill A. K. McPherson C. J. Oblinger E. T. Furlong M. T. Meyer

2007-01-01

16

Pesticide Fact Sheet Number 103: cadmium pesticide compounds  

SciTech Connect

The document contains up-to-date chemical information, including a summary of the Agency's regulatory position and rationale, on a specific pesticide or group of pesticides. A Fact Sheet is issued after one of the following actions has occurred. (1) Issuance or reissuance of a registration standard, (2) Issuance of each special review document, (3) Registration of a significantly changed use pattern, (4) Registration of a new chemical, or (5) An immediate need for information to resolve controversial issues relating to a specific chemical or use pattern.

Not Available

1986-09-01

17

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

Code of Federal Regulations, 2013 CFR

...Applicability; description of the metallo-organic pesticide chemicals manufacturing subcategory...CONTINUED) PESTICIDE CHEMICALS Metallo-Organic Pesticide Chemicals Manufacturing Subcategory...Applicability; description of the metallo-organic pesticide chemicals manufacturing...

2013-07-01

18

Organic Compounds Database  

NSDL National Science Digital Library

The Colby College Department of Chemistry offers the Organic Compounds Database, which was compiled by Harold Bell of the Virginia Polytechnic Institute. Visitors can search by the compounds melting point, boiling point, index of refraction, molecular weight, formula, absorption wavelength, mass spectral peak, chemical type, and by partial name. Once entered, results are returned with basically the same type of information that can be searched, plus any other critical information. References are provided for the close to 2500 organic compounds included in the database; yet, because the site was last modified in 1995, varying the data may be required to fully authenticate its accuracy.

Bell, Harold M.

2000-01-01

19

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

Microsoft Academic Search

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

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

2010-01-01

20

40 CFR 158.2060 - Biochemical pesticides nontarget organisms and environmental fate data requirements table.  

Code of Federal Regulations, 2010 CFR

...2009-07-01 2009-07-01 false Biochemical pesticides nontarget organisms and environmental...PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2060 Biochemical pesticides nontarget organisms and...

2009-07-01

21

40 CFR 158.2060 - Biochemical pesticides nontarget organisms and environmental fate data requirements table.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Biochemical pesticides nontarget organisms and environmental...PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2060 Biochemical pesticides nontarget organisms and...

2013-07-01

22

40 CFR 158.2084 - Experimental use permit biochemical pesticides nontarget organisms and environmental fate data...  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Experimental use permit biochemical pesticides nontarget organisms and... DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2084 Experimental use permit biochemical pesticides nontarget organisms...

2013-07-01

23

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...

24

SAMPLING FOR ORGANIC COMPOUNDS  

EPA Science Inventory

The methods of sampling ambient air for organic compounds for subsequent analysis are discussed. The following methods of sample collection are presented and the advantages and disadvantages of each is given: concentration of component of interest on to solid sorbents, into liqui...

25

Organic carbon normalisation of PCB, PAH and pesticide concentrations in suspended solids  

Microsoft Academic Search

The equilibrium partitioning concept for hydrophobic organic compounds (HOCs) predicts that organic carbon (OC) normalised or organic matter (OM) normalised HOC concentrations are approximately the same for different solid types sampled at the same time from the same surface water. This hypothesis was tested for polyaromatic hydrocarbon (PAH), polychlorobiphenyl (PCB) and pesticide concentrations in settling solids (sediment trap) and suspended

Albert A. Koelmans; Frits Gillissen; Willeke Makatita; Mark Van Den Berg

1997-01-01

26

Pesticides and other organic micro pollutants in the river Elbe  

Microsoft Academic Search

The main components of organic micro pollution regularly found in the river Elbe, belong to the wide spectrum of pesticides, nitro and chloro benzenes and the chelating agents, especially ethylenediaminetetraacetic acid (EDTA). The level of organic micro pollution with pesticides and the other organic micro pollutants in the upper and middle reaches of the river Elbe between Schmilka and Wittenberge

J. Pietsch; W. Schmidt; F. Sacher; S. Fichtner; H.-J. Brauch

1995-01-01

27

Acute toxicity of several pesticides, organic compounds, and a wastewater effluent to the freshwater mussel, Anodonta imbecilis, Ceriodaphnia dubia , and Pimephales promelas  

Microsoft Academic Search

Under the Endangered Species Act (PL 100-707), the federal government is mandated to protect listed species. This protection may go as far as the establishment of label restrictions for pesticide use in areas with sensitive endangered species. However, it is impossible to set valid standards or limits without appropriate data. With the current designation of over 40 species of freshwater

Anne E. Keller

1993-01-01

28

Chemical reactions of organic compounds on clay surfaces  

SciTech Connect

Chemical reactions of organic compounds including pesticides at the interlayer and exterior surfaces of clay minerals and with soil organic matter are reviewed. Representative reactions under moderate conditions possibly occurring in natural soils are described. Attempts have been made to clarify the importance of the chemical nature of molecules, their structures and their functional groups, and the Broensted or Lewis acidity of clay minerals.

Soma, Yuko; Soma, Mitsuyuki (National Institute for Environmental Studies, Ibaraki (Japan))

1989-11-01

29

Chemical reactions of organic compounds on clay surfaces.  

PubMed Central

Chemical reactions of organic compounds including pesticides at the interlayer and exterior surfaces of clay minerals and with soil organic matter are reviewed. Representative reactions under moderate conditions possibly occurring in natural soils are described. Attempts have been made to clarify the importance of the chemical nature of molecules, their structures and their functional groups, and the Brönsted or Lewis acidity of clay minerals.

Soma, Y; Soma, M

1989-01-01

30

Organic Compounds in Carbonaceous Meteorites.  

National Technical Information Service (NTIS)

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 bes...

G. Cooper

2001-01-01

31

Using organic-certified rather than synthetic pesticides may not be safer for biological control agents: selectivity and side effects of 14 pesticides on the predator Orius laevigatus.  

PubMed

The generalist predator Orius laevigatus (Fieber) (Hemiptera: Anthocoridae) is a key natural enemy of various arthropods in agricultural and natural ecosystems. Releases of this predator are frequently carried out, and it is included in the Integrated Pest Management (IPM) programs of several crops. The accurate assessment of the compatibility of various pesticides with predator activity is key for the success of this strategy. We assessed acute and sublethal toxicity of 14 pesticides on O. laevigatus adults under laboratory conditions. Pesticides commonly used in either conventional or organic farming were selected for the study, including six biopesticides, three synthetic insecticides, two sulfur compounds and three adjuvants. To assess the pesticides' residual persistence, the predator was exposed for 3d to pesticide residues on tomato sprouts that had been treated 1 h, 7 d or 14 d prior to the assay. The percentage of mortality and the sublethal effects on predator reproductive capacity were summarized in a reduction coefficient (E(x)) and the pesticides were classified according to the IOBC (International Organization for Biological Control) toxicity categories. The results showed that the pesticides greatly differed in their toxicity, both in terms of lethal and sub lethal effects, as well as in their persistence. In particular, abamectin was the most noxious and persistent, and was classified as harmful up to 14 d after the treatment, causing almost 100% mortality. Spinosad, emamectin, metaflumizone were moderately harmful until 7 d after the treatment, while the other pesticides were slightly harmful or harmless. The results, based on the combination of assessment of acute mortality, predator reproductive capacity pesticides residual and pesticides residual persistence, stress the need of using complementary bioassays (e.g. assessment of lethal and sublethal effects) to carefully select the pesticides to be used in IPM programs and appropriately time the pesticides application (as function of natural enemies present in crops) and potential releases of natural enemies like O. laevigatus. PMID:22342338

Biondi, Antonio; Desneux, Nicolas; Siscaro, Gaetano; Zappalà, Lucia

2012-02-17

32

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.

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

2010-01-01

33

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

PubMed

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 constituent detected in almost all samples. The chlorobenzenes accumulate in the marine food web in a similar manner to the better-studied persistent organic pollutants, with maximum concentrations in beluga, minke whale and narwhal. However, concentrations in ringed seals and kittiwakes were lower than in marine fish, contradicting biomagnification. Of the organochlorine pesticides, the drin pesticides (aldrin, endrin, dieldrin) and heptachlor had increasing concentrations along the food chain, whilst biomagnification was less pronounced for endosulfan, methoxychlor and mirex. Endosulfan and methoxychlor are pesticides still in use and considered less persistent than other organochlorine pesticides. Their occurrence in Arctic biota is of particular concern, also given the high acute toxicity of endosulfan to fish. Chlorobenzene and pesticide concentrations tended to be lower in the Greenland samples than in the same animals from the Canadian Arctic, whilst their concentrations were similar to samples from Svalbard and Iceland. However, temporal trends might overlap the geographical differences. Coplanar chlorobiphenyls (CBs) were found in all samples analysed, with the maximum concentrations found in marine mammals such as beluga and narwhal. Biota from the terrestrial environment appeared to be less contaminated. The main contributor on a TEQ basis was CB126. OCS, HCBD and PCA were detected in biota from Greenland, although at very low concentrations. OCS seems to have the widest occurrence and the highest potential for biomagnification of the three compounds analysed. PMID:15325147

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

2004-09-20

34

Pesticides  

Microsoft Academic Search

Organophosphorus (OP) pesticides can be rapidly detected by integrating organophosphorus hydrolase with an optical leaky waveguide biosensor. This enzyme catalyses the hydrolysis of a wide range of organophosphorus compounds causing an increase in the pH. Thus, the direct detection of OP is possible by monitoring of the pH changes associated with the enzyme's activity. This article describes the use of

A C Frazer; A. Simonian; J. Wild; S. Mohr; N. J. Goddarda

1967-01-01

35

(Energies of organic compounds)  

Microsoft Academic Search

The first part of our study of the enthalpy of reduction of carbonyl compounds has been completed and includes four aldehydes, acetone, a series of cyclic ketones and ethyl acetate. The results suggest that some of the literature data for these compounds are significantly in error. Equilibrium constants have been measured for the reaction of carbonyl compounds with water to

Wiberg

1989-01-01

36

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

37

Thermodynamics of organic compounds  

Microsoft Academic Search

Basic and applied research have continued on the thermodynamic properties of currently used high density\\/high energy fuels and of pure chemical compounds that may be constituents of high energy fuels of the future. Enthalpy of combustion was measured for three compounds that are constituents of current ramjet fuels--hexacyclic exo, exo-dihydrodinorbornadiene, hexacyclic endo, endo-dihydrodinorbornadiene and exo-tetrahydrodicyclopentadiene (JP-10). Heat capacities of exo-tetrahydrodicyclopentadiene

W. D. Good; R. H. P. Thomas; B. E. Gammon; S. Lee-Bechtold; J. E. Callanan; N. K. Smith

1980-01-01

38

Pesticides  

Center for Food Safety and Applied Nutrition (CFSAN)

... Pesticides. USDA's Pesticide Data Program. * Documents temporarily unavailable on the web. ? -. Guidance. Guidance for ... More results from www.fda.gov/food/foodborneillnesscontaminants/pesticides

39

The Role of Natural Organic Matter (Humic Substances) on Adsorption of Pesticides Possessing Endocrine Disruptor Activity  

Microsoft Academic Search

In this paper an overview is provided of adsorption processes of representative persistent organic pollutants (POPs), in particular\\u000a atrazine, alachlor and cis- and trans-chlordane pesticides with endocrine disruptor activity, by humic acids (HAs), the most abundant and chemically and biochemically\\u000a active fractions of humified natural organic matter in soil. Endocrine disruptor compounds (EDCs) are hormone-like substances\\u000a able to alter, i.e.,

E. Loffredo; N. Senesi

40

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.

41

Thermodynamics of organic compounds  

NASA Astrophysics Data System (ADS)

Basic and applied research have been continued on the thermodynamic properties of currently used high density/high energy fuels and of pure chemical compounds that may be constituents of high energy fuels of the future. Enthalpy of combustion was measured for three compounds that are constituents of current ramjet fuels--hexacyclic exo, exo-dihydrodinorbornadiene, hexacyclic endo, endo-dihydrodinorbornadiene and exo-tetrahydrodicyclocpentadiene (JP-10). Heat capacities of exo-tetrahydrodicyclopentadiene (JP-10) and RJ-6, a blend of JP-10 and the hydrogenated dimers of norbornadiene, were measured by differential scanning calorimetry. Enthalpy of combustion was measured for two pure hydrocarbons, 1,7-dimethylindan and 1,4-dimethyl-2-isobutylbenzene, that are expected to have high steric interaction energies of alkyl substituents in the ring structure, and measurements are in progress on 1-ethyl-8-methylnaphthalene and 1,6-dimethylindan.

Good, W. D.; Smith, N. K.; Thomas, R. H. P.; Gammon, B. E.; Lee-Bechtold, S.

1980-09-01

42

Sorption of hydrophobic pesticides on a Mediterranean soil affected by wastewater, dissolved organic matter and salts.  

PubMed

Irrigation with treated wastewaters as an alternative in countries with severe water shortage may influence the sorption of pesticides and their environmental effects, as wastewater contains higher concentrations of suspended and dissolved organic matter and inorganic compounds than freshwater. We have examined the sorption behaviour of three highly hydrophobic pesticides (the herbicide pendimethalin and the insecticides ?-cypermethrin and deltamethrin) on a Mediterranean agricultural soil using the batch equilibration method. We considered wastewater, extracts from urban sewage sludge with different dissolved organic carbon contents, and inorganic salt solutions, using Milli Q water as a control. All pesticides were strongly retained by soil although some sorption occurred on the walls of the laboratory containers, especially when wastewater and inorganic salt solutions were used. The calculation of distribution constants by measuring pesticide concentrations in soil and solution indicated that pendimethalin sorption was not affected whereas ?-cypermethrin and deltamethrin retention were significantly enhanced (ca. 5 and 2 times, respectively) when wastewater or salt solutions were employed. We therefore conclude that the increased sorption of the two pesticides caused by wastewater cannot be only the result of its dissolved organic carbon content, but also of the simultaneous presence of inorganic salts in the solution. PMID:20980092

Rodríguez-Liébana, José A; Mingorance, Ma Dolores; Peña, Aránzazu

2010-10-25

43

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

PubMed Central

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 children’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 urinary concentrations of the specific metabolites for malathion and chlorpyrifos decreased to the nondetect levels immediately after the introduction of organic diets and remained nondetectable until the conventional diets were reintroduced. The median concentrations for other organophosphorus pesticide metabolites were also lower in the organic diet consumption days; however, the detection of those metabolites was not frequent enough to show any statistical significance. In conclusion, we were able to demonstrate that an organic diet provides a dramatic and immediate protective effect against exposures to organophosphorus pesticides that are commonly used in agricultural production. We also concluded that these children were most likely exposed to these organophosphorus pesticides exclusively through their diet. To our knowledge, this is the first study to employ a longitudinal design with a dietary intervention to assess children’s exposure to pesticides. It provides new and persuasive evidence of the effectiveness of this intervention.

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

2006-01-01

44

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

45

Biodegradation of halogenated organic compounds.  

PubMed

In this review we discuss the degradation of chlorinated hydrocarbons by microorganisms, emphasizing the physiological, biochemical, and genetic basis of the biodegradation of aliphatic, aromatic, and polycyclic compounds. Many environmentally important xenobiotics are halogenated, especially chlorinated. These compounds are manufactured and used as pesticides, plasticizers, paint and printing-ink components, adhesives, flame retardants, hydraulic and heat transfer fluids, refrigerants, solvents, additives for cutting oils, and textile auxiliaries. The hazardous chemicals enter the environment through production, commercial application, and waste. As a result of bioaccumulation in the food chain and groundwater contamination, they pose public health problems because many of them are toxic, mutagenic, or carcinogenic. Although synthetic chemicals are usually recalcitrant to biodegradation, microorganisms have evolved an extensive range of enzymes, pathways, and control mechanisms that are responsible for catabolism of a wide variety of such compounds. Thus, such biological degradation can be exploited to alleviate environmental pollution problems. The pathways by which a given compound is degraded are determined by the physical, chemical, and microbiological aspects of a particular environment. By understanding the genetic basis of catabolism of xenobiotics, it is possible to improve the efficacy of naturally occurring microorganisms or construct new microorganisms capable of degrading pollutants in soil and aquatic environments more efficiently. Recently a number of genes whose enzyme products have a broader substrate specificity for the degradation of aromatic compounds have been cloned and attempts have been made to construct gene cassettes or synthetic operons comprising these degradative genes. Such gene cassettes or operons can be transferred into suitable microbial hosts for extending and custom designing the pathways for rapid degradation of recalcitrant compounds. Recent developments in designing recombinant microorganisms and hybrid metabolic pathways are discussed. PMID:2030673

Chaudhry, G R; Chapalamadugu, S

1991-03-01

46

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

47

Xenobiotic organic compounds in leachates from ten Danish MSW landfills—chemical analysis and toxicity tests  

Microsoft Academic Search

A monitoring program comprising chemical analysis and biological toxicity testing of leachate samples from 10 Danish landfills (six engineered and four uncontrolled) revealed the presence of 55 different xenobiotic organic compounds (XOCs) and 10 degradation products of XOCs. The compounds belong to the following groups: BTEX, C3-benzenes, bicyclo compounds, napthalenes, chlorinated aliphatics, phenols (chloro-, methyl-, dimethyl, nonyl-), pesticides, and phthalates.

A. Baun; A. Ledin; L. A. Reitzel; P. L. Bjerg; T. H. Christensen

2004-01-01

48

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

Code of Federal Regulations, 2011 CFR

...Environment 30 2011-07-01 2011-07-01 false Organic Pesticide Active Ingredient New Source Performance Standards...PESTICIDE CHEMICALS Pt. 455, Table 3 Table 3 to Part 455âOrganic Pesticide Active Ingredient New Source Performance...

2011-07-01

49

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

Code of Federal Regulations, 2011 CFR

...Environment 30 2011-07-01 2011-07-01 false Organic Pesticide Active Ingredient Effluent Limitations Best Available...PESTICIDE CHEMICALS Pt. 455, Table 2 Table 2 to Part 455âOrganic Pesticide Active Ingredient Effluent Limitations Best...

2011-07-01

50

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

Code of Federal Regulations, 2013 CFR

...Environment 31 2013-07-01 2013-07-01 false Organic Pesticide Active Ingredient Effluent Limitations Best Available...PESTICIDE CHEMICALS Pt. 455, Table 2 Table 2 to Part 455âOrganic Pesticide Active Ingredient Effluent Limitations Best...

2013-07-01

51

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

Code of Federal Regulations, 2013 CFR

...Environment 31 2013-07-01 2013-07-01 false Organic Pesticide Active Ingredient New Source Performance Standards...PESTICIDE CHEMICALS Pt. 455, Table 3 Table 3 to Part 455âOrganic Pesticide Active Ingredient New Source Performance...

2013-07-01

52

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

53

European scenarios for exposure of soil organisms to pesticides.  

PubMed

Standardised exposure scenarios play an important role in European pesticide authorisation procedures (a scenario is a combination of climate, weather and crop data to be used in exposure models). The European Food Safety Authority developed such scenarios for the assessment of exposure of soil organisms to pesticides. Scenarios were needed for both the concentration in total soil and for the concentration in the liquid phase. The goal of the exposure assessment is the 90th percentile of the exposure concentration in the area of agricultural use of a pesticide in each of three regulatory European zones (North, Centre and South). A statistical approach was adopted to find scenarios that are consistent with this exposure goal. Scenario development began with the simulation of the concentration distribution in the entire area of use by means of a simple analytical model. In the subsequent two steps, procedures were applied to account for parameter uncertainty and scenario uncertainty (i.e. the likelihood that a scenario that is derived for one pesticide is not conservative enough for another pesticide). In the final step, the six scenarios were selected by defining their average air temperature, soil organic-matter content and their soil textural class. Organic matter of the selected scenarios decreased in the order North-Centre-South. Because organic matter has a different effect on the concentration in total soil than it has on the concentration in the liquid phase, the concentration in total soil decreased in the order North-Centre-South whereas the concentration in the liquid phase decreased in the opposite order. The concentration differences between the three regulatory zones appeared to be no more than a factor of two. These differences were comparatively small in view of the considerable differences in climate and soil properties between the three zones. PMID:23688221

Tiktak, Aaldrik; Boesten, Jos J T I; Egsmose, Mark; Gardi, Ciro; Klein, Michael; Vanderborght, Jan

2013-01-01

54

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

55

Industrial Electrosynthesis of Organic Compounds.  

National Technical Information Service (NTIS)

Electrochemical methods are beginning to find uses in the synthesis of different classes of organic compounds with a high degree of purity. The processes of electrochemical synthesis in large-tonnage of some monomers are of special interest because of the...

M. Y. Fioshin A. P. Tomilov

1968-01-01

56

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, ...

57

Preliminary Assessment of Relative Toxicity of Several Pesticide Compounds in Behavioral Screening Tests.  

National Technical Information Service (NTIS)

Four pesticide compounds were tested for detrimental effects on the behavior of rats trained to avoid electric shock in a modified shuttlebox procedure. ED50 values ('effective dose' for producing nonresponse in 50 percent of the subjects) were determined...

W. M. Smith

1974-01-01

58

Characterization and mass load estimates of organic compounds in agricultural irrigation runoff.  

PubMed

Investigations of agricultural chemicals in surface runoff typically target nutrients or specific pesticides; however, numerous other organic compounds are regularly applied to agricultural fields in pesticide formulations, irrigation water, soil amendments and fertilizers. Many of these compounds have toxicological significance. We conducted a broad spectrum analysis of surface runoff from individual irrigated agricultural fields in coastal southern California to characterize organic compounds amenable to analysis by gas chromatography-mass spectrometry and to estimate the mass flux of selected chemicals. Aqueous phase extracts contained several pesticides, as well as personal care product ingredients and pharmaceutically active compounds apparently derived from treated wastewater used for irrigation. Several compounds potentially associated with pesticide adjuvants were also present in aqueous phase extracts. Dissolved NOM constituents in water phase extracts included n-fatty acids, aliphatic alcohols and plant terpenoids. Tentatively identified compounds sorbed to suspended particles included pesticides, a fecal sterol, aliphatic and alicyclic hydrocarbons, aliphatic alcohols, aldehydes, and C14 and C16 n-fatty acids and fatty acid esters. Bicyclic and polycyclic aromatic hydrocarbons were identified in both aqueous and suspended particle phases. Constituent concentrations, including total suspended solids (TSS), varied over the course of the sampled events by up to an order of magnitude, and typically were not correlated with flow. Variation in sorbed organic compound concentrations often did not parallel those for TSS concentration. Mass load estimates were strongly influenced by the choice of sampling interval. PMID:12079091

Pedersen, J A; Yeager, M A; Suffet, I H Mel

2002-01-01

59

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.

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

2012-01-01

60

[Detection of organic compounds on Mars].  

PubMed

McKay et al. detected polycyclic aromatic hydrocarbons (PAHs) in Martian meteorite ALH 84001 by two-step laser mass spectrometry. From the presence of PAHs, together with other results, they concluded that there were past life of Mars. On the other hands, no organisms nor organic compounds were detected in Martian regolith in Viking experiments in 1976. In order to obtain solid evidence for organisms or bioorganic compounds compounds on Mars, further analyses of Martian samples are required. There may be four classes of organic compounds on Mars, which are (i) organic compounds abiotically formed from primitive Mars atmosphere, (ii) Organic compounds delivered out of Mars, (iii) Organic compounds biotically formed by Mars organisms, and (iv) Organic compounds abiotically formed from the present Mars atmosphere. Possible organic compounds on Mars and analytical methods for them are discussed. PMID:11540350

Kobayashi, K

1997-03-01

61

Toxicity of halogenated organic compounds. (Latest citations from the NTIS bibliographic database). Published Search  

SciTech Connect

The bibliography contains citations concerning health and environmental effects of halogenated organic compounds. Topics include laboratory and field investigations regarding bioaccumulation and concentration, metabolic aspects, and specific site studies in industrial and commercial operations. Pesticides, solvents, and a variety of industrial compounds are discussed. (Contains 250 citations and includes a subject term index and title list.)

Not Available

1993-09-01

62

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...

63

Pesticide residues in Portuguese strawberries grown in 2009-2010 using integrated pest management and organic farming.  

PubMed

Pesticides are among the most widely used chemicals in the world. Because of the widespread use of agricultural chemicals in food production, people are exposed to low levels of pesticide residues through their diets. Scientists do not yet have a total understanding of the health effects of these pesticide residues. This work aims to determine differences in terms of pesticide residue content in Portuguese strawberries grown using different agriculture practices. The Quick, Easy, Cheap, Effective, Rugged, and Safe sample preparation method was conducted and shown to have good performance for multiclass pesticides extraction in strawberries. The screening of 25 pesticides residue was performed by gas chromatography-tandem mass spectrometry. In quantitative validation, acceptable performances were achieved with recoveries of 70-120 and <12 % residual standard deviation for 25 pesticides. Good linearity was obtained for all the target compounds, with highly satisfactory repeatability. The limits of detection were in the range of 0.1-28 ?g/kg. The method was applied to analyze strawberry samples from organic and integrated pest management (IPM) practices harvested in 2009-2010. The results showed the presence of fludioxonil, bifenthrin, mepanipyrim, tolylfluanid, cyprodinil, tetraconazole, and malathion when using IPM below the maximum residue levels. PMID:22562348

Fernandes, Virgínia C; Domingues, Valentina F; Mateus, Nuno; Delerue-Matos, Cristina

2012-05-05

64

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

PubMed

To determine if current sheep/beef farming practices affect pesticide residues in streams, current-use and legacy chlorinated pesticides were quantified in 100 sediment samples from 15 streams on the South Island of New Zealand. The study involved five blocks of three neighboring farms, with each block containing farms managed by organic, integrated and conventional farming practices. Significantly higher concentrations of dieldrin, ? endosulfans, ? current-use pesticides, and ? chlorinated pesticides were measured in sediments from conventional farms compared to organic and integrated farms. However, streams in the latter two farming categories were not pesticide-free and sometimes contained relatively high concentrations of legacy pesticides. Comparison of measured pesticide concentrations with sediment quality guidelines showed that, regardless of farming practice, mean pesticide concentrations were below the recommended toxicity thresholds. However, up to 23% of individual samples contained chlorpyrifos, endosulfan sulfate, ? DDT, dieldrin, or ? chlordane concentrations above these thresholds. PMID:23871819

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

2013-07-17

65

Pesticides  

MedlinePLUS

... pesticides are regulated by the U.S. Department of Agriculture. This agency for how pesticides are applied during ... NOT place food scraps in the garden for birds or possums. Throw out any food left in ...

66

Vapor-particle partitioning of semivolatile organic compounds: estimates from field collections  

Microsoft Academic Search

Pesticides, polychlorinated biphenyls (PCB), and other semivolatile organic compounds (SOC) exist in air as vapors and are associated with particulate matter. Factors influencing the vapor-to-particle distribution can be obtained from high-volume sampling experiments using a glass-fiber filter to collect particles and an adsorbent trap to collect vapors. Measurements of airborne organochlorine pesticides and PCB in four cities over a wide

Terry F. Bidleman; W. Neil Billings; William T. Foreman

1986-01-01

67

Low volatile organic compound paints  

SciTech Connect

Increasingly stringent air emission standards in various states has dictated the elimination of engineering finishes which are derived from high volatile organic compound (VOC) paint chemistries. In July 1989, Allied-Signal, Inc., Kansas City Division, Kansas City, Missouri, voluntarily closed its paint facility, due to non-compliance with local air emission standards. The following details the materials selection and evaluations which led to current processing using low VOC paints, which permitted the Allied Signal, Inc., paint facility to achieve compliance and resume operations. 1 tab.

Martinez, F.E.

1991-01-01

68

Rejection of trace organic compounds by high-pressure membranes.  

PubMed

High-pressure membranes, encompassing reverse osmosis (RO), nanofiltration (NF), and low-pressure RO, may provide an effective treatment barrier for trace organic compounds including disinfection by-products (DBPs), pesticides, solvents, endocrine disrupting compounds (EDCs) and pharmaceutically active compounds (PhACs). The objective is to develop a mechanistic understanding of the rejection of trace organic compounds by high-pressure membranes, based on an integrated framework of compound properties, membrane properties, and operational conditions. Eight trace organic compounds, four DBPs and four chlorinated (halogenated) solvents, are being emphasized during an initial study, based on considerations of compound properties, occurrence, and health effects (regulations). Four polyamide FilmTec membranes; three reverse osmosis/RO (BW-400, LE-440, XLE-440) and one nanofiltration/NF (NF-90); are being characterized according to pure water permeability (PWP), molecular weight cutoff (MWCO), hydrophobicity (contact angle), and surface charge (zeta potential). It is noteworthy that rejections of compounds of intermediate hydrophobicity by the candidate membranes were observed to be less than salt rejections reported for these membranes, suggesting that transport of these solutes through these membranes is facilitated by solute-membrane interactions. We are continuing with diffusion cell measurements to describe solute-membrane interactions by estimation of diffusion coefficients through membranes pores, either hindered or facilitated. PMID:16003994

Kim, T U; Amy, G; Drewes, J E

2005-01-01

69

Perfluorinated Compounds, Polychlorinated Biphenyls, and Organochlorine Pesticide Contamination in Composite Food Samples from Dallas, Texas, USA  

PubMed Central

Objectives The objective of this article is to extend our previous studies of persistent organic pollutant (POP) contamination of U.S. food by measuring perfluorinated compounds (PFCs), organochlorine pesticides, and polychlorinated biphenyls (PCBs) in composite food samples. This study is part of a larger study reported in two articles, the other of which reports levels of polybrominated diphenyl ethers and hexabromocyclododecane brominated flame retardants in these composite foods [Schecter et al. 2010. Polybrominated diphenyl ethers (PBDEs) and hexabromocyclodecane (HBCD) in composite U.S. food samples, Environ Health Perspect 118:357–362]. Methods In this study we measured concentrations of 32 organochlorine pesticides, 7 PCBs, and 11 PFCs in composite samples of 31 different types of food (310 individual food samples) purchased from supermarkets in Dallas, Texas (USA), in 2009. Dietary intake of these chemicals was calculated for an average American. Results Contamination varied greatly among chemical and food types. The highest level of pesticide contamination was from the dichlorodiphenyltrichloroethane (DDT) metabolite p,p?- dichlorodiphenyldichloroethylene, which ranged from 0.028 ng/g wet weight (ww) in whole milk yogurt to 2.3 ng/g ww in catfish fillets. We found PCB congeners (28, 52, 101, 118, 138, 153, and 180) primarily in fish, with highest levels in salmon (PCB-153, 1.2 ng/g ww; PCB-138, 0.93 ng/g ww). For PFCs, we detected perfluorooctanoic acid (PFOA) in 17 of 31 samples, ranging from 0.07 ng/g in potatoes to 1.80 ng/g in olive oil. In terms of dietary intake, DDT and DDT metabolites, endosulfans, aldrin, PCBs, and PFOA were consumed at the highest levels. Conclusion Despite product bans, we found POPs in U.S. food, and mixtures of these chemicals are consumed by the American public at varying levels. This suggests the need to expand testing of food for chemical contaminants.

Schecter, Arnold; Colacino, Justin; Haffner, Darrah; Patel, Keyur; Opel, Matthias; Papke, Olaf; Birnbaum, Linda

2010-01-01

70

Electroreduction of Halogenated Organic Compounds  

NASA Astrophysics Data System (ADS)

The electroreductive cleavage of the carbon-halogen bond in halogenated organic compounds has been extensively studied for more than 70 years, since it is prodromal to a large variety of synthetic applications in organic electrochemistry. Over the years the research interest have progressively included the environmental applications, since several organic halocompounds are known to have (or have had) a serious environmental impact because of their (present or past) wide use as cleaning agents, herbicides, cryogenic fluids, reagents (e.g. allyl and vinyl monomers) for large production materials, etc. Recent studies have also demonstrated the wide spread out- and in-door-presence of volatile organic halides, although at low level, in connexion with residential and non-residential (e.g. stores, restaurants and transportation) activities. In this context, the detoxification of emissions to air, water and land by the selective removal of the halogen group represents a valid treatment route, which, although not leading to the complete mineralization of the pollutants, produces less harmful streams to be easily treated by electrochemical or conventional techniques. The electroreduction process is analysed and discussed in terms of electrode material, reaction medium, cell design and operation, and of substrate classification.

Rondinini, Sandra; Vertova, Alberto

71

Pesticides  

Microsoft Academic Search

\\u000a Pesticides include plant protection and biocidal products. Many pesticides are hazardous to human health. Dermal exposure\\u000a may cause systemic toxic effects, dermatitis, or other skin effects. The use of pesticides in Europe and Northern America\\u000a is regulated for the protection of the environment and health, while severe problems are caused in developing countries. Adequate\\u000a protective equipment, working conditions, and awareness

Carola Lidén

72

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

73

Organic compounds in municipal landfill leachates  

Microsoft Academic Search

Leachates from three municipal landfills in the Göteborg area of western Sweden were characterised in terms of their content of individual organic compounds. Two of the investigated landfills were still in use during the time of this study. The third landfill was closed down in the mid-seventies. More than 200 individual organic compounds and classes of compounds were identified in

N. Paxéus

2000-01-01

74

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

Code of Federal Regulations, 2013 CFR

...Environment 31 2013-07-01 2013-07-01 false List of Organic Pesticide Active Ingredients 1 Table 1 to Part 455 Protection...CHEMICALS Pt. 455, Table 1 Table 1 to Part 455âList of Organic Pesticide Active Ingredients EPA census code...

2013-07-01

75

Organochlorine pesticide residues in strawberries from integrated pest management and organic farming.  

PubMed

A rapid, specific, and sensitive method based on the Quick Easy Cheap Effective Rugged and Safe (QuEChERS) method and a cleanup using dispersive solid-phase extraction with MgSO(4), PSA, and C18 sorbents has been developed for the routine analysis of 14 pesticides in strawberries. The analyses were performed by three different analytical methodologies: gas chromatography (GC) with electron capture detection (ECD), mass spectrometry (MS), and tandem mass spectrometry (MS/MS). The recoveries for all the pesticides studied were from 46 to 128%, with relative standard deviation of <15% in the concentration range of 0.005-0.250 mg/kg. The limit of detection (LOD) for all compounds met maximum residue limits (MRL) accepted in Portugal for organochlorine pesticides (OCP). A survey study of strawberries produced in Portugal in the years 2009-2010 obtained from organic farming (OF) and integrated pest management (IPM) was developed. Lindane and ?-endosulfan were detected above the MRL in OF and IPM. Other OCP (aldrin, o,p'-DDT and their metabolites, and methoxychlor) were found below the MRL. The OCP residues detected decreased from 2009 to 2010. The QuEChERS method was successfully applied to the analysis of strawberry samples. PMID:21235274

Fernandes, Virginia C; Domingues, Valentina F; Mateus, Nuno; Delerue-Matos, Cristina

2011-01-10

76

Labeling of Pesticide Products under the National Organic Program.  

National Technical Information Service (NTIS)

This notice describes how registrants can obtain Environmental Protection Agency (EPA) approval of label language indicating that all ingredients (active and inert) in a pesticide product and all uses of that pesticide meet the criteria defined in the Uni...

2002-01-01

77

Results of the fifth joint pesticide testing programme carried out by the IOBC\\/WPRS-Working Group “Pesticides and beneficial organisms  

Microsoft Academic Search

Laboratory, semi field and field tests to assess the side effects of 20 pesticides on 19 different beneficial organisms were\\u000a carried out by members of the Working Group “Pesticides and Beneficial Organisms” of the International Organization for Biological\\u000a Control (IOBC), West Palearctic Regional Section (WPRS). This 5th joint pesticide testing programme of the working group was carried out by 21

S. A. Hassan; F. Bigler; H. Bogenschütz; E. Boller; J. Brun; J. COREMANS-PELSENEER; P. Chiverton; C. Duso; G. B. Lewis; F. Mansour; L. Moreth; P. A. Oomen; W. P. J. Overmeer; L. Polgar; W. Rieckmann; L. Samsøe-Petersen; A. Stäubli; G. Sterk; K. Tavares; J. J. Tuset; G. Viggiani

1991-01-01

78

Results of the sixth joint pesticide testing programme of the IOBC\\/WPRS-working group «pesticides and beneficial organisms»  

Microsoft Academic Search

The side effects of 5 insecticides, 8 fungicides and 6 herbicides on 24 species of beneficial organisms were tested by members\\u000a of the Working Group «Pesticides and Beneficial Organisms» of the International Organization for Biological Control (IOBC),\\u000a West Palaearctic Regional Section (WPRS). The tests were conducted by 24 members in 11 countries according to internationally\\u000a approved guidelines.\\u000a \\u000a The insecticide buprofezin

S. A. Hassan; F. Bigler; H. Bogenschütz; E. Boller; J. Brun; J. N. M. Calis; J. Coremans-Pelseneer; C. Duso; A. Grove; U. Heimbach; N. Helyer; H. Hokkanen; G. B. Lewis; F. Mansour; L. Moreth; L. Polgar; L. Samsøe-Petersen; B. Sauphanor; A. Stäubli; G. Sterk; A. Vainio; M. van de Veire; G. Viggiani; H. Vogt

1994-01-01

79

Use of raw or incubated organic wastes as amendments in reducing pesticide leaching through soil columns.  

PubMed

Soil amendment with organic wastes is becoming a widespread management practice since it can effectively solve the problems of uncontrolled waste accumulation and improve soil quality. However, when simultaneously applied with pesticides, organic wastes can significantly modify the environmental behaviour of these compounds. This study evaluated the effect of sewage sludges (SS), grape marc (GM) and spent mushroom substrates (SMS) on the leaching of linuron, diazinon and myclobutanil in packed columns of a sandy soil with low organic matter (OM) content (<1%). Soil plus amendments had been incubated for one month (1 m) or 12 months (12 m). Data from the experimental breakthrough curves (BTCs) were fitted to the one-dimensional transport model CXTFIT 2.1. All three amendments reduced leaching of linuron and myclobutanil relative to unamended soil. SMS was the most effective in reducing leaching of these two compounds independent of whether soil was incubated for 1 m or 12 m. Soil amendments increased retardation coefficients (Rexp) by factors of 3 to 5 for linuron, 2 to 4 for diazinon and 3 to 5 for myclobutanil relative to unamended soil. Leaching of diazinon was relatively little affected by soil amendment compared to the other two compounds and both SS and SMS amendment with 1m incubation resulted in enhanced leaching of diazinon. The leaching data for linuron and myclobutanil were well described by CXTFIT (mean square error, MSE<4.9·10(-7) and MSE<7.0·10(-7), respectively) whereas those of diazinon were less well fitted (MSE<2.1·10(-6)). The BTCs for pesticides were similar in soils incubated for one month or one year, indicating that the effect of amendment on leaching persists over relatively long periods of time. PMID:23835069

Marín-Benito, J M; Brown, C D; Herrero-Hernández, E; Arienzo, M; Sánchez-Martín, M J; Rodríguez-Cruz, M S

2013-07-05

80

Toxicities of “excessively” chlorinated organic compounds  

Microsoft Academic Search

It is now recognized that chlorine can combine with a large variety of organics present in waste waters to form stable organochlorinated compounds (JOLLEY 1973). Moreover, the possible entry of these stable organochlorines into supplies of drinking water has prompted the monitoring of these compounds in many localities (EPA 1974, HARRIS 1974). JOLLEY (1973) identified seventeen stable organochlorine compounds in

Bernice M. Katz; Glenn M. Cohen

1976-01-01

81

Analysis of Volatile Organic Compounds.  

National Technical Information Service (NTIS)

An improved system is described for reproducibly analyzing, both qualitatively and quantitatively, trace amounts of a large number of organic volatiles existing in a gas sample. Applications include: (1) analyzing the headspace gas of body fluids and comp...

A. Zlatkis

1974-01-01

82

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...

83

Thermodynamic properties of organic iodine compounds  

NASA Astrophysics Data System (ADS)

A critical evaluation has been made of the thermodynamic properties reported in the literature for 43 organic iodine compounds in the solid, liquid, or ideal gas state. These compounds include aliphatic, cyclic and aromatic iodides, iodophenols, iodocarboxylic acids, and acetyl and benzoyl iodides. The evaluation has been made on the basis of carbon number systematics and group additivity relations, which also allowed to provide estimates of the thermodynamic properties of those compounds for which no experimental data were available. Standard molal thermodynamic properties at 25 °C and 1 bar and heat capacity coefficients are reported for 13 crystalline, 29 liquid, and 39 ideal gas organic iodine compounds, which can be used to calculate the corresponding properties as a function of temperature and pressure. Values derived for the standard molal Gibbs energy of formation at 25 °C and 1 bar of these crystalline, liquid, and ideal gas organic iodine compounds have subsequently been combined with either solubility measurements or gas/water partition coefficients to obtain values for the standard partial molal Gibbs energies of formation at 25 °C and 1 bar of 32 aqueous organic iodine compounds. The thermodynamic properties of organic iodine compounds calculated in the present study can be used together with those for aqueous inorganic iodine species to predict the organic/inorganic speciation of iodine in marine sediments and petroleum systems, or in the near- and far-field of nuclear waste repositories.

Richard, Laurent; Gaona, Xavier

2011-11-01

84

[Studies on adsorption of the organic phosphorus pesticide with the macroporous resin].  

PubMed

Macroporous adsorbing resins prepared by styrene are selected as absorbent in the static and dynamic adsorption experiments of organic phosphorus pesticide. These resins are attempted to be applied in blood purification to detoxify and save the patient's life. PMID:11211815

Li, G; Yang, B; Li, C; Chen, Y; Guo, X; He, B; Zhang, Y; Dai, R

2000-12-01

85

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. ...

86

VOLATILE ORGANIC COMPOUNDS AS EXPOSURE BIOMARKERS  

EPA Science Inventory

Alveolar breath sampling and analysis can be extremely useful in exposure assessment studies involving volatile organic compounds (VOCs). Over recent years scientists from the US Environmental Protection Agency's National Exposure Research Laboratory have developed and refined...

87

BIORESTORATION OF AQUIFERS CONTAMINATED WITH ORGANIC COMPOUNDS  

EPA Science Inventory

Techniques available to remediate ground water contaminated with organic compounds. These include physical containment, in situ treatment with chemicals or microbes, and withdrawal and treatment via various forms of physical, chemical, or biological processes. (Copyright (c) CRC ...

88

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.

Farrington, J W

1991-01-01

89

(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...

90

FREQUENCY OF ORGANIC COMPOUNDS IDENTIFIED IN WATER  

EPA Science Inventory

This study was initiated for the purpose of compiling a list of all organic compounds that have been found in water. This report contains the names of compounds found, their location or a reference to a published study, the type of water in which they are found, and the date of s...

91

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

92

Organic Compounds used in Aquaculture  

Microsoft Academic Search

The transport patterns and potential direct or indirect effects on the environment or even on human health of agents used\\u000a in aquaculture like antibiotics, triphenylmethane dyes and hormones used to modify sex ratios have barely been defined. Even\\u000a at trace levels, hormones may influence the endocrine systems of non-target organisms due to their high biological low-dose\\u000a activity. Antibiotics are often

Thomas Heberer

93

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

94

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

95

The Effect of an Organic Pesticide on Mortality and Learning in Africanized Honey Bees (Apis mellifera L.) in Brasil  

Microsoft Academic Search

Seven experiments were conducted. First, the influence of the consumption of different concentrations of the organic pesticide Bioganic ® on mortality was assessed at 11 different time intervals in Africanized honey bees (Apis mellifera L.) as was direct application of the pesticide to the abdomen. Results indicated that the pesticide was not lethal to bees regardless of concentration at any

Charles I. Abramson; Jordan B. Singleton; Maritza K. Wilson; Paulo A. Wanderley

2006-01-01

96

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

SciTech Connect

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 water, and those that have relatively high octanol-to-water partition coefficients or low water solubility have a high potential for bioconcentration. Based on these findings, researchers should be able to predict the mobility of pesticides belonging to a particular category or family of compounds with unknown physicochemical properties and recommend ways to restore the environment. 13 refs., 13 figs., 4 tabs.

Prasad, S.S.

1991-01-01

97

Regulatory Off-Gas Analysis from the Evaporation of Hanford Simulated Waste Spiked with Organic Compounds  

SciTech Connect

After strontium/transuranics removal by precipitation followed by cesium/technetium removal by ion exchange, remaining low activity waste in the Hanford River Protection Project Waste Treatment Plant is to be concentrated by evaporation prior to being mixed with glass formers and vitrified. To provide a technical basis to permit the waste treatment facility, a relatively organic-rich Hanford Tank 241-AN-107 waste simulant was spiked with 14 target volatile, semi-volatile and pesticide compounds, and evaporated under vacuum in a bench-scale natural circulation evaporator fitted with an industrial stack off-gas sampler at the Savannah River Technology Center. An evaporator material balance for the target organics was calculated by combining liquid stream mass and analytical data with off-gas emissions estimates obtained using EPA SW-846 Methods. Volatile and light semi-volatile organic compounds in the waste simulant were found to largely exit through the condenser vent, while heavier semi-volatiles and pesticides generally remain in the evaporator concentrate. An OLI Environmental Simulation Program evaporator model successfully predicted operating conditions and the experimental distribution of the fed target organics exiting in the concentrate, condensate and off-gas streams with the exception of a few semi-volatile and pesticide compounds. Comparison with Henry's Law predictions suggests the OLI ESP model is constrained by available literature data.

Calloway, T.B. Jr.

2003-10-23

98

Compendium of methods for the determination of toxic organic compounds in ambient air  

SciTech Connect

Determination of toxic organic compounds in ambient air is a complex task, primarily because of the wide variety of compounds of interest and the lack of standardized sampling and analysis procedures. This compendium of methods was prepared to provide current, peer-reviewed procedures in a standardized, written format for measuring toxic organic pollutants of primary importance in ambient air. The various methods provide both sampling and analytical procedures for a variety of pollutants, including pesticides, PCBs, formaldehyde and other aldehydes, phosgene, n-nitrosodimethylamine, cresol/phenol, dioxin, non-speciated non-methane organic compounds, polynuclear aromatic hydrocarbons, and various other volatile nonpolar organic compounds. The compendium is a consolidation and republishing of Methods T01-105 from the original Compendium (EPA 600/4-84-041), Methods T06-T09 from the First Supplement (EPA-600/4-87-006), and T010-T014 from the Second Supplement (EPA-600/4-89/018).

Riggin, R.M.; Winberry, W.T.; Murphy, N.T.

1988-06-01

99

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

100

Sulfate minerals and organic compounds on Mars  

NASA Astrophysics Data System (ADS)

Strong evidence for evaporitic sulfate minerals such as gypsum and jarosite has recently been found on Mars. Although organic molecules are often codeposited with terrestrial evaporitic minerals, there have been no systematic investigations of organic components in sulfate minerals. We report here the detection of organic material, including amino acids and their amine degradation products, in ancient terrestrial sulfate minerals. Amino acids and amines appear to be preserved for geologically long periods in sulfate mineral matrices. This suggests that sulfate minerals should be prime targets in the search for organic compounds, including those of biological origin, on Mars.

Aubrey, Andrew; Cleaves, H. James; Chalmers, John H.; Skelley, Alison M.; Mathies, Richard A.; Grunthaner, Frank J.; Ehrenfreund, Pascale; Bada, Jeffrey L.

2006-05-01

101

40 CFR 180.1127 - Biochemical pesticide plant floral volatile attractant compounds: cinnamaldehyde, cinnamyl...  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Biochemical pesticide plant floral volatile attractant...Exemptions From Tolerances § 180.1127 Biochemical pesticide plant floral volatile...of a tolerance. Residues of the biochemical pesticide plant floral...

2013-07-01

102

Group-specific fragmentation of pesticides and related compounds in liquid chromatography-tandem mass spectrometry.  

PubMed

Current strategies in the LC-MS analysis of pesticides and related compounds in environmental samples, fruits and vegetables, and biological samples mostly rely on the selection of appropriate precursor/product-ion combinations (transitions) for selected reaction monitoring (SRM), often based on automated parameter optimization and selection of the transition. Such a procedure does not require any information on the type of fragmentation reaction involved in the generation of the product ion from the selected precursor ion. However, such information does become important in untargeted screening for unknown contaminants in environmental and food samples, which are generally based on a combination of high-resolution mass spectrometry and (multistage) tandem mass spectrometry. With this in mind, the group-specific fragmentation behaviour has been studied for six classes of pesticides and herbicides, i.e., triazines, organophosphorous pesticides, phenylurea herbicides, carbamates, sulfonylurea herbicides, and chlorinated phenoxy acid herbicides. When relevant, some comparison was made between fragmentation of protonated molecules in MS-MS and of molecular ions generated by electron ionization in GC-MS. PMID:19815223

Niessen, W M A

2009-09-26

103

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

104

Volatile Organic Compounds Fibre Optic Nanosensor  

Microsoft Academic Search

A novel vapochromic material of formula (Au2Ag2(C6F5)4(C6H5N)2) has been used to develop a volatile organic compounds (VOCs) sensor. This product changes its optical properties, such as colour or refractive index, when exposed to some organic vapours. The sensor consists of a nanometer-scale Fizeau interferometer doped with the above mentioned vapochromic complex and built onto a cleaved end of a multimode

César Elosúaa; Cándido Bariáina; Ignacio R. Matías; Francisco J. Arreguia; Asunción Luquin; Mariano Laguna; Julián Garrido

105

Trace organic compounds in the marine environment  

Microsoft Academic Search

Trace organic chemicals include a range of compounds which, due to a combination of their physico-chemical properties and toxicological implications, have been described as a serious threat to the biotic environment. A global treaty to regulate the manufacture and release of some of the most persistent trace chemicals has been promulgated and signed.The marine environment is an important sink for

Michael R Moore; Walter Vetter; Caroline Gaus; Glen R Shaw; Jochen F Müller

2002-01-01

106

RAPID MICRODETERMINATION OF FLUORINE IN ORGANIC COMPOUNDS  

Microsoft Academic Search

In a rapid and accurate method for the microdetermination of fluorine in ; organic compounds the Schoniger combustion technique is used for initial ; decomposition of the sample, followed by an improved ferric salicylate ; colorimetric analysis. Samples ranging from 0.4 to 20 mg. were successfully ; analyzed in 10 to 20 minutes. Accuracy and precision are adequate for ;

R. N. Rogers; S. K. Yasuda

1959-01-01

107

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

108

Attitudes towards organic foods and risk\\/benefit perception associated with pesticides  

Microsoft Academic Search

A sample of 947 subjects completed a questionnaire assessing attitudes and beliefs towards the consumption of organic fruits and vegetables. A section of the questionnaire was aimed at assessing the role of trust on perception of risks and benefits associated with pesticides on foods. The subjects tended to hold positive attitudes towards eating fruits and vegetables produced by organic agriculture.

Anna Saba; Federico Messina

2003-01-01

109

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

110

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.

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

1982-01-01

111

Organic Compounds in Savannah River Site High-Level Waste  

SciTech Connect

The present study identifies organic compounds or classes of compounds that may occur in SRS high-level waste (HLW) based on a review of previous sample analyses and records of disposals of organic compounds to the HLW tank farms.

Walker, D.D.

2002-12-17

112

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

113

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

114

Analysis of industrial contaminants in indoor air: part 1. Volatile organic compounds, carbonyl compounds, polycyclic aromatic hydrocarbons and polychlorinated biphenyls.  

PubMed

This article reviews recent literature on the analysis of industrial contaminants in indoor air in the framework of the REACH project, which is mainly intended to improve protection of human health and the environment from the risks of more than 34 millions of chemical substances. Industrial pollutants that can be found in indoor air may be of very different types and origin, belonging to the volatile organic compounds (VOCs) and semivolatile organic compounds (SVOCs) categories. Several compounds have been classified into the priority organic pollutants (POPs) class such as polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and furans (PCDD/PCDFs) and related polychlorinated compounds, and polycyclic aromatic hydrocarbons (PAHs). Many of these compounds are partially associated to the air gas phase, but also to the suspended particulate matter. Furthermore, settled dust can act as a concentrator for the less volatile pollutants and has become a matrix of great concern for indoors contamination. Main literature considered in this review are papers from the last 10 years reporting analytical developments and applications regarding VOCs, aldehydes and other carbonyls, PCBs, PCDDs, PCDFs, and PAHs in the indoor environment. Sample collection and pretreatment, analyte extraction, clean-up procedures, determination techniques, performance results, as well as compound concentrations in indoor samples, are summarized and discussed. Emergent contaminants and pesticides related to the industrial development that can be found in indoor air are reviewed in a second part in this volume. PMID:19019381

Barro, Ruth; Regueiro, Jorge; Llompart, María; Garcia-Jares, Carmen

2008-11-06

115

Organic Aerosols: A Potential Source of Oxygenated Volatile Organic Compounds  

NASA Astrophysics Data System (ADS)

Numerous laboratory studies have demonstrated that organic surfaces are readily oxidized by O3 and OH, in many cases producing oxygenated volatile organic compounds (OVOC) such as aldehydes and organic acids. Because many aerosols possess organic coatings, it is possible that oxidation of organic aerosol surfaces could provide a significant flux of OVOC into the troposphere that is not accounted for in current models. From data collected on the NASA DC-8 during INTEX-NA over North America in the summer of 2004 (part of ICARTT -- the International Consortium for Atmospheric Research on Transport and Transformation), we estimate the potential flux of OVOC from organic aerosol oxidation, and discuss its implications for our understanding of atmospheric photochemistry.

Kwan, A. J.; Crounse, J. D.; Wennberg, P. O.

2005-12-01

116

Synthesis and Characterization of Organic NLO Compound  

NASA Astrophysics Data System (ADS)

Organic compound 1-(2 thiophene)-3-(2, 3, 5-trichloroph enyl)-2-propen-1-one [TTCP] with molecular formula C13H7Cl3OS was synthesized using condensation reaction method. FT-IR spectra were recorded to identify the various functional groups present in the compound. The third harmonic optical nonlinearity test was carried out using z-scan technique. The single crystals were grown using slow evaporation solution growth technique. Optical absorption studies reveal that the crystal is transparent in the entire visible region and absorption (around 364 nm) takes place in the UV-region. The single-crystal XRD studies were carried out, and it was found that the compound crystallizes in the monoclinic system with a space group P21/c. The observed lattice parameters are a = 16.6170(6) A? b = 7.6180(5) A? c = 10.9280(11) A? and V = 1338.47(17) A?3.

Kumar, P. C. Rajesh; Ravindrachary, V.; Janardhana, K.; Manjunath, H. R.; Karegoudar, Prakash

2011-07-01

117

Results of the seventh joint pesticide testing programme carried out by the IOBC\\/WPRS-Working Group ‘Pesticides and Beneficial Organisms  

Microsoft Academic Search

The side effect of 10 insecticides, 5 fungicides and 5 herbicides on 24 different species of beneficial organisms was tested by members of the Working Group Pesticides and Beneficial Organisms of the International Organization for Biological Control (IOBC), West Palaearctic Regional Section (WPRS). The tests were conducted by 32 members in 12 countries according to internationally approved guidelines.The microbial insecticides

G. Sterk; S. A. Hassan; M. Baillod; F. Bakker; F. Bigler; S. Blümel; H. Bogenschütz; E. Boller; B. Bromand; J. Brun; J. N. M. Calis; J. Coremans-Pelseneer; C. Duso; A. Garrido; A. Grove; U. Heimbach; H. Hokkanen; J. Jacas; G. Lewis; L. Moreth; L. Polgar; L. Rovesti; L. Samsoe-Peterson; B. Sauphanor; L. Schaub; A. Stäubli; J. J. Tuset; A. Vainio; M. Van de Veire; G. Viggiani; E. Viñuela; H. Vogt

1999-01-01

118

Tyrosinase inhibition organic phase biosensor for triazinic and benzotriazinic pesticide analysis (part two).  

PubMed

Several triazine pesticides, such as atrazine, are much more soluble in several organic solvents, such as chloroform, than in water. Our recent research was aimed at analyzing this class of pesticides using tyrosinase OPEE (organic phase enzyme electrodes), exploiting their inhibiting action on the tyrosinase enzyme when operating in water-saturated chloroform medium. In this work we studied the response of a tyrosinase inhibition enzyme sensor to several triazinic (simazine, propazine, terbuthylazine) and benzotriazinic (azinphos-ethyl and azinphos-methyl) pesticides (LOD=0.5x10(-9) mol l(-1)). Recovery trials were also performed in vegetal matrixes (corn, barley, lentils). Lastly, the effect of the solvent (chloroform or water) on the inhibition process was investigated via Hill's equation and the diffusion of analyte from the solvent to the enzyme membrane. PMID:16328240

Campanella, L; Dragone, R; Lelo, D; Martini, E; Tomassetti, M

2005-12-03

119

Microbiological degradation of atmospheric organic compounds  

NASA Astrophysics Data System (ADS)

Until now, aerosol transformation was assumed to be via chemical or physical processes. Here we present evidence that an important class of organic aerosols - dicarboxylic acids (DCA) - can be efficiently transformed by existing airborne microbes (bacteria and fungi) in the boundary layer. Isotopic studies indicate that microbiological entities transform and use DCA as nutrients. Several observed products are toxicants or pathogens. Identified volatile products indicate that DCA can be recycled back to the atmosphere via microbiological processes. Thus, biodegradation could be an important atmospheric transformation pathway for organic compounds.

Ariya, Parisa A.; Nepotchatykh, Oleg; Ignatova, Olga; Amyot, Marc

2002-11-01

120

Volatile organic compounds (VOCs) in soils  

Microsoft Academic Search

Soils may act as sources or sinks of volatile organic compounds (VOCs). Many of the formed VOCs are produced by microorganisms,\\u000a and it would be a challenge to investigate soil microbial communities by studying their VOC profile. Such “volatilomics” would\\u000a have the advantage of avoiding extraction steps that are often a limit in genomic or proteomic approaches. Abundant literature\\u000a on

Heribert Insam; Martin S. A. Seewald

2010-01-01

121

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

122

Organic foods contain higher levels of certain nutrients, lower levels of pesticides, and may provide health benefits for the consumer.  

PubMed

The multi-billion dollar organic food industry is fueled by consumer perception that organic food is healthier (greater nutritional value and fewer toxic chemicals). Studies of the nutrient content in organic foods vary in results due to differences in the ground cover and maturity of the organic farming operation. Nutrient content also varies from farmer to farmer and year to year. However, reviews of multiple studies show that organic varieties do provide significantly greater levels of vitamin C, iron, magnesium, and phosphorus than non-organic varieties of the same foods. While being higher in these nutrients, they are also significantly lower in nitrates and pesticide residues. In addition, with the exception of wheat, oats, and wine, organic foods typically provide greater levels of a number of important antioxidant phytochemicals (anthocyanins, flavonoids, and carotenoids). Although in vitro studies of organic fruits and vegetables consistently demonstrate that organic foods have greater antioxidant activity, are more potent suppressors of the mutagenic action of toxic compounds, and inhibit the proliferation of certain cancer cell lines, in vivo studies of antioxidant activity in humans have failed to demonstrate additional benefit. Clear health benefits from consuming organic dairy products have been demonstrated in regard to allergic dermatitis. PMID:20359265

Crinnion, Walter J

2010-04-01

123

Alternatives for hazardous waste management in the organic chemical, pesticides and explosives industries. Final report  

Microsoft Academic Search

Potential alternative treatment methods are evaluated for a total of 24 waste streams selected from the report 'Assessment of Industrial Hazardous Waste Practices of the Organic Chemicals, Pesticides and Explosives Industries'. Potential alternatives are physical, chemical and biological processes identified in the report 'Analysis of Potential Application of Physical, Chemical and Biological Treatment Techniques to Hazardous Waste Management'. The primary

J. M. Genser; A. H. Zipperstein; S. P. Klosky; P. S. Farber

1977-01-01

124

Maximum permissible and negligible concentrations for some organic substances and pesticides  

Microsoft Academic Search

The aim of the paper is to provide interested parties the methods that were used for generic hazard assessment in The Netherlands, and the resulting so-called maximum permissible concentrations (MPCs) and the negligible concentrations (NCs) for approximately 150 organic substances and pesticides. The MPCs and NCs were derived for water, sediment, and soil. The concentration in the environment above which

T. Crommentuijn; D. Sijm; J. de Bruijn; K. van Leeuwen; E. van de Plassche

2000-01-01

125

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

126

40 CFR 180.1127 - Biochemical pesticide plant floral volatile attractant compounds: cinnamaldehyde, cinnamyl...  

Code of Federal Regulations, 2010 CFR

...1127 Biochemical pesticide plant floral volatile attractant...of the biochemical pesticide plant floral volatile attractant...cauliflower), collards (kale, mustard greens, turnip greens, kohlrabi...cucumbers, squash, pumpkin), egg plant, endive (escarole),...

2010-07-01

127

40 CFR 180.1127 - Biochemical pesticide plant floral volatile attractant compounds: cinnamaldehyde, cinnamyl...  

Code of Federal Regulations, 2010 CFR

...1127 Biochemical pesticide plant floral volatile attractant...of the biochemical pesticide plant floral volatile attractant...cauliflower), collards (kale, mustard greens, turnip greens, kohlrabi...cucumbers, squash, pumpkin), egg plant, endive (escarole),...

2009-07-01

128

A review of the tissue residue approach for organic and organometallic compounds in aquatic organisms.  

PubMed

This paper reviews the tissue residue approach (TRA) for toxicity assessment as it applies to organic chemicals and some organometallic compounds (Sn, Hg, and Pb) in aquatic organisms. Specific emphasis was placed on evaluating key factors that influence interpretation of critical body residue (CBR) toxicity metrics including data quality issues, lipid dynamics, choice of endpoints, processes that alter toxicokinetics and toxicodynamics, phototoxicity, species- and life stage-specific sensitivities, and biotransformation. The vast majority of data available on TRA is derived from laboratory studies of acute lethal responses to organic toxicants exhibiting baseline toxicity. Application of the TRA to various baseline toxicants as well as substances with specific modes of action via receptor-mediated processes, such as chlorinated aromatic hydrocarbons, pesticides, and organometallics is discussed, as is application of TRA concepts in field assessments of tissue residues. In contrast to media-based toxicity relationships, CBR values tend to be less variable and less influenced by factors that control bioavailability and bioaccumulation, and TRA can be used to infer mechanisms of toxic action, evaluate the toxicity of mixtures, and interpret field data on bioaccumulated toxicants. If residue-effects data are not available, body residues can be estimated, as has been done using the target lipid model for baseline toxicants, to derive critical values for risk assessment. One of the primary unresolved issues complicating TRA for organic chemicals is biotransformation. Further work on the influence of biotransformation, a better understanding of contaminant lipid interactions, and an explicit understanding of the time dependency of CBRs and receptor-mediated toxicity are all required to advance this field. Additional residue-effects data on sublethal endpoints, early life stages, and a wider range of legacy and emergent contaminants will be needed to improve the ability to use TRA for organic and organometallic compounds. PMID:21184569

McElroy, Anne E; Barron, Mace G; Beckvar, Nancy; Driscoll, Susan B Kane; Meador, James P; Parkerton, Tom F; Preuss, Thomas G; Steevens, Jeffery A

2010-12-09

129

Process optimization using a kinetic model for the ultraviolet radiation-hydrogen peroxide decomposition of natural and synthetic organic compounds in groundwater  

Microsoft Academic Search

This paper discusses the application of ultraviolet radiation-hydrogen peroxide (UV-HP) process as an advanced oxidation process (AOP) in the treatment of source waters containing natural organic matter (NOM) and contaminated with a synthetic organic chemical (SOC) exemplified by alachlor, an acetanilide pesticide. Alachlor was chosen as the model compound owing to its hydrophobicity and propensity to complex with NOM, besides

Wonho Song; Varadarajan Ravindran; Massoud Pirbazari

2008-01-01

130

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...

131

Preparing Soil Samples for Volatile Organic Compound Analysis.  

National Technical Information Service (NTIS)

Three equilibrium headspace and three solvent extraction methods of preparing soil samples for determining volatile organic compounds (VOCs) were compared. Soil samples were spiked with five gasoline range aromatic compounds and four chlorinated compounds...

A. D. Hewitt

1997-01-01

132

Antiandrogenic activity and metabolism of the organophosphorus pesticide fenthion and related compounds.  

PubMed Central

We investigated the endocrine-disrupting actions of the organophosphorus pesticide fenthion and related compounds and the influence of metabolic transformation on the activities of these compounds. Fenthion acted as an antagonist of the androgenic activity of dihydrotestosterone (10(-7)M) in the concentration range of 10(-6)-10(-4)M in an androgen-responsive element-luciferase reporter-responsive assay using NIH3T3 cells. The antiandrogenic activity of fenthion was similar in magnitude to that of flutamide. Fenthion also tested positive in the Hershberger assay using castrated male rats. Marked estrogenic and antiestrogenic activities of fenthion and related compounds were not observed in MCF-7 cells. When fenthion was incubated with rat liver microsomes in the presence of NADPH, the antiandrogenic activity markedly decreased, and fenthion sulfoxide was detected as a major metabolite. The oxidase activity toward fenthion was exhibited by cytochrome P450 and flavin-containing monooxygenase. Fenthion sulfoxide was negative in the screening test for antiandrogens, as was fenthion sulfone. However, when fenthion sulfoxide was incubated with liver cytosol in the presence of 2-hydroxypyrimidine, an electron donor of aldehyde oxidase, the extract of the incubation mixture exhibited antiandrogenic activity. In this case, fenthion was detected as a major metabolite of the sulfoxide. Metabolic interconversion between fenthion and fenthion sulfoxide in the body seems to maintain the antiandrogenic activity.

Kitamura, Shigeyuki; Suzuki, Tomoharu; Ohta, Shigeru; Fujimoto, Nariaki

2003-01-01

133

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

134

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

135

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

136

Effect of organic species on the solar detoxification of water polluted with pesticides.  

PubMed

The effect of organic species on a solar-driven photo-Fenton treatment of a mixture of pesticides (methyl-oxydemethon, methidathion, carbaryl and dimethoate) has been studied in this paper. Triethoxyisododecyl alcohol, acetophenone and ethylenediaminetetraacetic acid (EDTA) have been used as examples of surfactants, solvents and complexing agents, respectively. An inhibitory effect on mineralization as well as on the elimination of the pesticides was observed in the case of the aliphatic surfactants, most probably due to the competition between the pesticides and the added organic matter for reaction with the relatively unselective hydroxyl radical. A methodology combining chemical analyses and bioassays was tested in order to explore the applicability of coupling a photo-Fenton process with a biological treatment in the presence of the surfactant. Despite the complexity of the mixture under study, a reliable monitoring of the process was accomplished; the biocompatibility of the mixture was enhanced and the optimal irradiation intensity was achieved just after complete removal of the pesticides. PMID:21353387

Soler, J; Santos-Juanes, L; Miró, P; Vicente, R; Arques, A; Amat, A M

2011-01-28

137

Alternatives to Automotive Consumer Products That Use Volatile Organic Compounds (VOC) and/or Chlorinated Organic Compound Solvents. Addendum.  

National Technical Information Service (NTIS)

This addendum to the document entitled 'Alternatives to Automotive Consumer Products that use Volatile Organic Compounds (VOC) and/or Chlorinated Organic Compound Solvents' presents the questionnaires that were filled out by the staff of the Institute for...

D. Wolf J. Zavadil M. Morris

2004-01-01

138

IRRADIATION METHOD OF CONVERTING ORGANIC COMPOUNDS  

DOEpatents

A method is given for changing the distribution of organic compounds from that produced by the irradiation of bulk alkane hydrocarbons. This method consists of depositing an alkane hydrocarbon on the surface of a substrate material and irradiating with gamma radiation at a dose rate of more than 100,000 rads. The substrate material may be a metal, metal salts, metal oxides, or carbons having a surface area in excess of 1 m/sup 2//g. The hydrocarbons are deposited in layers of from 0.1 to 10 monolayers on the surfaces of these substrates and irradiated. The product yields are found to vary from those which result from the irradiation of bulk hydrocarbons in that there is an increase in the quantity of branched hydrocarbons.

Allen, A.O.; Caffrey, J.M. Jr.

1960-10-11

139

A quantitative determination of organophosphate pesticides in organic solvents  

Microsoft Academic Search

An amperometric acetylcholinesterase (AChE) biosensor based on thiocholine-hexacyanoferrate reaction was developed for the analysis of OPCs in pure organic solvents. The enzyme (AChE) was co-immobilized with an electron mediator, Prussian Blue, on the surface of a graphite electrode. The effect of organic solvents on acetylcholinesterase activity was estimated in the presence of polar (hydrophilic) and non-polar (hydrophobic) organic solvents in

E Wilkins; M Carter; J Voss; D Ivnitski

2000-01-01

140

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...

141

Determination of pesticide residues in Turkey's table grapes: the effect of integrated pest management, organic farming, and conventional farming.  

PubMed

Turkey is one of the world's largest producers and exporters of table grapes. Growing social concerns over excessive pesticide use have led to farming to move from conventional to organic practices. Table grapes were collected from 99 different farms in three Aegean regions. Pesticide residues were only detected in farms using conventional agriculture practices while no pesticides were detected in grapes from farms using organic or integrated pest management. A risk assessment model indicated that lambda-cyhalothrin posed the most significant risk at conventional farms. PMID:20213057

Turgut, Cafer; Ornek, Hakan; Cutright, Teresa J

2010-03-07

142

Organochlorine pesticide residues in bovine milk from organic farms in Chiapas, Mexico.  

PubMed

Thirty six samples of bovine milk were collected from Chiapas State, Mexico between January 2011 and December 2011 with the intention of identifying and quantifying organochlorine pesticide residues in organic farms. The analyses were done using gas chromatography with an electron capture detector (Ni(63)). In general the values found in raw milk were lower than the permissible limit proposed by FAO/WHO/Codex Alimentarius 2006. Average concentrations for alpha + beta HCH were 3.62 ng/g, gamma HCH 0.34 ng/g, heptachlor + epoxide 0.67 ng/g, DDT and isomers 1.53 ng/g, aldrin + dieldrin 0.77 ng/g, and endrin 0.66 ng/g (only present in samples from farm 2). The organic milk from Chiapas has shown low concentrations of pesticide residues in recent years and satisfies international and national regulations for commercialization. PMID:22864634

Gutiérrez, Rey; Ruíz, Jorge Luis; Ortiz, Rutilio; Vega, Salvador; Schettino, Beatriz; Yamazaki, Alberto; de Lourdes Ramírez, María

2012-08-05

143

Sediment contamination of residential streams in the metropolitan kansas city area, USA: Part I. distribution of polycyclic aromatic hydrocarbon and pesticide-related compounds  

USGS Publications Warehouse

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 pesticide-related 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 ??g/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. Historical-use 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. ?? 2010 Springer Science+Business Media, LLC.

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

2010-01-01

144

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

PubMed

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. PMID:17363035

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

2007-03-23

145

Selected trace-element and synthetic-organic compound data for streambed sediment from the Clark Fork-Pend Oreille and Spokane River basins, Montana, Idaho, and Washington, 1998  

USGS Publications Warehouse

Most of the analytical results for synthetic organic compounds were reported as either estimated or non-detected values. Phthalates and polycyclic aro­matic hydrocarbons were the most frequently detected classes of synthetic organic compounds in streambed sediment. Organochlorine pesticide residues were detected at two sites. Polychlorinated biphenyls were detected at one site.

Beckwith, Michael A.

2002-01-01

146

Reduction of hazardous organic solvent in sample preparation for hydrophilic pesticide residues in agricultural products with conventional liquid chromatography.  

PubMed

An original extraction method using water as an extractant has been established for environmentally friendly sample preparation procedures for hydrophilic pesticides (acetamiprid, clothianidin, dinotefuran, flonicamid, imidacloprid, methomyl, pymetrozine, thiacloprid, and thiamethoxam) in agricultural samples with conventional HPLC. Water-based extraction and cleanup with two solid-phase extraction cartridges can recover target hydrophilic pesticides quantitatively. The matrix effects of tested samples on the proposed method developed herein were negligibly small. Under the optimized conditions, the recoveries of almost all tested pesticides were 70-120% with satisfactory precision (%CV < 20%). The analytical data are in good accordance with Japanese or European Union guidelines for pesticide residue analysis. The reduction rate of hazardous organic solvents used for the proposed method and by reducing the sample size for extraction was about 70% compared with the Japanese authorized reference method used in this work. The results demonstrate the feasibility of the proposed sample preparation procedures for hydrophilic pesticides. PMID:23614723

Watanabe, Eiki; Kobara, Yuso; Baba, Koji; Eun, Heesoo

2013-05-13

147

LC-MS-based procedures for monitoring of toxic organophosphorus compounds and verification of pesticide and nerve agent poisoning  

Microsoft Academic Search

Organophosphorus compounds (OPCs) are used worldwide as, e.g., flame retardants, plasticizers, and pesticides and remaining\\u000a stockpiles of OPC nerve agents are present in military arsenals. These OPCs exhibit acute and potential chronic toxicity to\\u000a man, the environment, and biota thus emphasizing the need for efficient analytical procedures to monitor potential risk to\\u000a health. Therefore, this review discusses LC-MS-based procedures for

Harald John; Franz Worek; Horst Thiermann

2008-01-01

148

New chemically modified polymeric resin for solid-phase extraction of pesticides and phenolic compounds from water  

Microsoft Academic Search

A new chemically modified polymeric resin, with an o-carboxybenzoyl moiety, is developed to be used in the on-line solid-phase extraction (SPE) of some pesticides and phenolic compounds from aqueous samples, in order to obtain better breakthrough volumes than other commercial sorbents. The chemical introduction of this moiety improves the efficiency of SPE by providing better surface contact with aqueous samples.

N Masqué; M Galià; R. M Marcé; F Borrull

1998-01-01

149

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

150

Shock Modifications of Organic Compounds in Carbonaceous Chondrite Parent Bodies  

Microsoft Academic Search

Impacts among asteroidal objects would have altered or destroyed pre-existing organic matter in both targets and projectiles to a greater or lesser degree depending upon impact velocities. To begin filling a knowledge gap on the shock metamorphism of organic compounds, we are studying the effects of shock impacts on selected classes of organic compounds utilizing laboratory shock facilities. Our approach

George W. Cooper

1998-01-01

151

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...

152

GLOBAL INVENTORY OF VOLATILE ORGANIC COMPOUND EMISSIONS FORM ANTHROPOGENIC SOURCES  

EPA Science Inventory

The report describes a global inventory anthropogenic volatile organic compound (VOC) emissions that includes a separate inventory for each of seven pollutant groups--paraffins, olefins, aromatics, formaldehyde, other aldehydes, other aromatics, and marginally reactive compounds....

153

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

154

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

155

Volatile Organic Compounds Contribute to Airway Hyperresponsiveness  

PubMed Central

Background Volatile organic compounds (VOCs) in concentrations found in both the work and home environments may influence lung function. We investigated the prevalence of airway responsiveness in workers exposed to VOCs. Methods We used allergic skin tests, nonspecific airway hyperresponsiveness testing and questionnaires to study twenty exposed workers and twenty-seven control subjects. Atopy was defined as a reactor who showed >3+ response to one or more allergens on the skin prick tests. Airway hyperresponsiveness (BRindex) was defined as log [% fall of FEV1/ log (last concentration of methacholine) +10]. Results The VOC exposed workers, in comparison with the control subjects, tended to have a higher BRindex (1.19±0.07 vs. 1.15±0.08, respectively). Workers exposed to VOCs with atopy or smoker, as compared with the workers exposed to VOCs with non-atopy and who were non-smokers and the control subjects with non-atopy and who were non-smokers, had a significantly higher BRindex (1.20±0.05 vs. 1.14±0.06 vs. 1.10±0.03, respectively p<0.05). The BRindex was not correlated with atopy, the smoking status or the duration of VOC exposure. Conclusions These findings suggest that VOCs may act as a contributing factor of airway hyperresponsiveness in workers exposed to VOCs.

Jang, An-Soo; Choi, Inseon-S; Koh, Young-Il

2007-01-01

156

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

157

Toxicological assessment of isomeric pesticides: a strategy for testing of chiral organophosphorus (OP) compounds for delayed polyneuropathy in a regulatory setting  

Microsoft Academic Search

Many compounds, including some pesticides, contain structural centres of asymmetry, which convey the property of a type of stereoisomerism known as chirality. Such compounds can exist in two or more forms, depending on the number of chiral atoms and are termed stereoisomers or enantiomers. Stereoisomers of a particular compound can have different biological properties; one such of particular importance for

Jon M. Battershill; Philippa M. Edwards; Martin K. Johnson

2004-01-01

158

Kinetics of desorption of organic compounds from dissolved organic matter.  

PubMed

This study presents a new experimental technique for measuring rates of desorption of organic compounds from dissolved organic matter (DOM) such as humic substances. The method is based on a fast solid-phase extraction of the freely dissolved fraction of a solute when the solution is flushed through a polymer-coated capillary. The extraction interferes with the solute-DOM sorption equilibrium and drives the desorption process. Solutes which remain sorbed to DOM pass through the extraction capillary and can be analyzed afterward. This technique allows a time resolution for the desorption kinetics from subseconds up to minutes. It is applicable to the study of interaction kinetics between a wide variety of hydrophobic solutes and polyelectrolytes. Due to its simplicity it is accessible for many environmental laboratories. The time-resolved in-tube solid-phase microextraction (TR-IT-SPME) was applied to two humic acids and a surfactant as sorbents together with pyrene, phenanthrene and 1,2-dimethylcyclohexane as solutes. The results give evidence for a two-phase desorption kinetics: a fast desorption step with a half-life of less than 1 s and a slow desorption step with a half-life of more than 1 min. For aliphatic solutes, the fast-desorbing fraction largely dominates, whereas for polycyclic aromatic hydrocarbons such as pyrene, the slowly desorbing, stronger-bound fraction is also important. PMID:22035249

Kopinke, Frank-Dieter; Ramus, Ksenia; Poerschmann, Juergen; Georgi, Anett

2011-11-10

159

Secondary organic aerosol from biogenic volatile organic compound mixtures  

NASA Astrophysics Data System (ADS)

The secondary organic aerosol (SOA) yields from the ozonolysis of a Siberian fir needle oil (SFNO), a Canadian fir needle oil (CFNO), and several SOA precursor mixtures containing reactive and non-reactive volatile organic compounds (VOCs) were investigated. The use of precursor mixtures more completely describes the atmosphere where many VOCs exist. The addition of non-reactive VOCs such as bornyl acetate, camphene, and borneol had very little to no effect on SOA yields. The oxidation of VOC mixtures with VOC mass percentages similar to the SFNO produced SOA yields that became more similar to the SOA yield from SFNO as the complexity and concentration of VOCs within the mixture became more similar to overall SFNO composition. The SOA yield produced by the oxidation of CFNO was within the error of the SOA yield produced by the oxidation of SFNO at a similar VOC concentration. The SOA yields from SFNO were modeled using the volatility basis set (VBS), which predicts the SOA yields for a given mass concentration of mixtures containing similar VOCs.

Hatfield, Meagan L.; Huff Hartz, Kara E.

2011-04-01

160

Separation of Organic Compounds from Surfactant Solutions: A Review  

Microsoft Academic Search

This review summarizes the recent development in separation of emulsified organic compounds from surfactant solutions for surfactant reuse and\\/or surfactant?contaminant disposal. Three major principles have been employed for separating organic compounds and\\/or surfactants from aqueous solutions, namely, organic compound inter?phase mass transfer, surfactant micelle removal, and manipulation of surfactant solution phase behavior. Details of these principles and their applications are

Hefa Cheng; David A. Sabatini

2007-01-01

161

Comparison of organochlorine pesticides and polychlorinated biphenyls residues in vegetables, grain and soil from organic and conventional farming in Poland  

Microsoft Academic Search

Organic and conventional crops were studied by identifying the relationship between persistent organic pollutants in cereals, vegetables and soil. The residues of organochlorine pesticides and polychlorinated biphenyls (PCBs) were determined in grains (rye and wheat), vegetables (carrots and beets) and soil collected from the fields. PCB residues recorded in the beets from organic farming were as high as 3.71 ppb

Agata Witczak; Hassan Abdel-Gawad

2012-01-01

162

Soil washing process for the removal of hydrophobic organic compounds from soils and sediments  

SciTech Connect

A new process concept for the removal of organic pollutants from soils and sediments is presented. The organic pollutants to be removed are primarily hydrophobic organic compounds (HOC), e.g. polychlorinated biphenyls, polychlorinated dioxins, polychlorinated dibenzofurans, penta-, tri- and monochlorophenols, polyaromatic hydrocarbons and pesticides. The main objectives of this process concept include: (1) the conversion of solid waste to a liquid waste for easier handling, (2) the achievement of a significant volume reduction of the initial waste stream and (3) the safe ultimate disposal of the reduced volume of the liquid waste containing the contaminants, with minimal energy expenditures. The four principal steps of the process are, solid-liquid separation, solvent leaching, liquid-liquid extraction and adsorption. An analytical model has been developed for the entire process, and is presented together with sample calculations for the individual steps. The model allows for the optimization of the process for any specified scenario.

Steiner, W.

1988-01-01

163

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

164

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

PubMed

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 (R(s)) was evaluated in microcosms containing <0.1-5 mg L(-1) of total organic carbon (TOC). The effect of hydrodynamics was studied by comparing R(s) 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. PMID:22705502

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

2012-06-15

165

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

166

POTENTIAL EMISSIONS OF HAZARDOUS ORGANIC COMPOUNDS FROM SEWAGE SLUDGE INCINERATION  

EPA Science Inventory

Laboratory thermal decomposition studies were undertaken to evaluate potential organic emissions from sewage sludge incinerators. Precisely controlled thermal decomposition experiments were conducted on sludge spiked with mixtures of hazardous organic compounds, on the mixtures o...

167

40 CFR 60.582 - Standard for volatile organic compounds.  

Code of Federal Regulations, 2010 CFR

...Subpart Fff - Standards of Performance for Flexible Vinyl and Urethane] [Sec. 60.582 - Standard for volatile organic compounds...SOURCES-- Standards of Performance for Flexible Vinyl and Urethane Sec. 60.582 Standard for volatile organic...

2009-07-01

168

Effects of Cr(III) organic compounds on Lactobacillus plantarum  

Microsoft Academic Search

Biotransformation of Cr(VI) to less toxic Cr(III) has been known to produce insoluble Cr(III) compounds and soluble Cr(III) organic complexes. However, recent research reports have indicated that Cr(III) organic complexes are relatively stable in the environment. Little has been reported on the fate and toxic effects of Cr(III) organic compounds on organisms. In this study, the toxic effects of the

Titus Wambua Mutisya; Zejiao Luo; Nivedita Chatterjee

2010-01-01

169

Nitrated Secondary Organic Tracer Compounds in Biomass Burning Smoke  

NASA Astrophysics Data System (ADS)

Natural and human-initiated biomass burning releases large amounts of gases and particles into the atmosphere, impacting climate, environment and affecting public health. Several hundreds of compounds are emitted from biomass burning and these compounds largely originate from the pyrolysis of biopolymers such as lignin, cellulose and hemicellulose. Some of compounds are known to be specific to biomass burning and widely recognized as tracer compounds that can be used to identify the presence of biomass burning PM. Detailed chemical analysis of biomass burning influenced PM samples often reveals the presence compounds that correlated well with levoglucosan, a known biomass burning tracer compound. In particular, nitrated aromatic compounds correlated very well with levoglucosan, indicating that biomass burning as a source for this class of compounds. In the present study, we present evidence for the presence of biomass burning originating secondary organic aerosol (BSOA) compounds in biomass burning influenced ambient PM. These BSOA compounds are typically nitrated aromatic compounds that are produced in the oxidation of precursor compounds in the presence of NOx. The precursor identification was performed from a series of aerosol chamber experiments. m-Cresol, which is emitted from biomass burning at significant levels, is found to be a major precursor compounds for nitrated BSOA compounds found in the ambient PM. We estimate that the total concentrations of these compounds in the ambient PM are comparable to biogenic SOA compounds in winter months, indicating the BSOA contributes important amounts to the regional organic aerosol loading.

Iinuma, Y.; Böge, O.; Gräfe, R.; Herrmann, H.

2010-12-01

170

Distribution of persistent organochlorine pesticides in tissue/organ of silver carp (Hypophthalmichthys molitrix) from Guanting Reservoir, China.  

PubMed

The concentration of organochlorine pesticides (OCPs) in tissues and organs of silver carp (Hypophthalmichthys molitrix) from Guanting Reservoir were investigated to evaluate the pollution potential and distribution of OCPs. A total of 16 OCPs were measured and the concentrations were in the range of 1.61-69.01 ng/g wet weight (ww) for total OCPs, 0.16-0.75 ng/g ww for. HCB, 0.75-26.80 ng/g ww for sigmaHCH (sum of alpha-, beta-, gamma- and delta-HCH) and 0.68-35.94 ng/g ww for sigmaDDT( sum of p, p'-DDE, p, p'-DDD, o, p'-DDT and p, p'-DDT). The mean concentrations of total OCPs, HCB, sigmaHCH, and sigmaDDT were 18.04, 0.96, 7.14 and 9.28 ng/g ww, respectively. Among the organochlorine pesticides, beta-HCH and p, p'-DDE were the most dominant compounds in tissue and organ with the average concentrations of 4.42 and 8.14 ng/g, respectively. The results obtained in this study show that the levels of 16 OCP residues found in silver carps are low and pose no threat to human health and wildlife fed upon them on the basis of existing related quality guidelines. However, recent input of lindane and DDT might still exist in the area investigated and further investigation should be carried on. PMID:16312991

Sun, Yang-zhao; Wang, Xue-tong; Li, Xing-hong; Xu, Xiao-bai

2005-01-01

171

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

National Technical Information Service (NTIS)

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 en...

S. S. Prasad

1991-01-01

172

Identification of Organic Compounds by Gas Chromatography  

Microsoft Academic Search

THE identification of unknown compounds separated by gas chromatography is often effected by comparison of their retention values with those of known compounds together with infra-red spectro-photometry or mass spectrometry. For this purpose graphs are prepared of log r against boiling point or log r on one stationary phase against log r on another stationary phase, where r is the

Ian Brown

1960-01-01

173

Volatile chelates and organic compounds of neptunium and plutonium  

SciTech Connect

In this review, volatile coordination and organic compounds of neptunium and plutonium are described, including complex halides, alkoxides, borohydrides, ..beta..-diketonates, phthalocyanines, and organometallic ..pi..-complexes. Comparison is made with analogous compounds of other f-elements (particularly, uranium and thorium). The prospects of practical use of volatile compounds of neptunium and plutonium are discussed.

Mishin, V.Ya.; Sidorenko, G.V.; Suglobov, D.N.

1987-01-01

174

Retention of pesticide Endosulfan by nanofiltration: influence of organic matter-pesticide complexation and solute-membrane interactions.  

PubMed

Nanofiltration (NF) is a well-established process used in drinking water production to effectively remove Natural Organic Matter (NOM) and organic micropollutants. The presence of NOM has been shown to have contrasting results on micropollutant retention by NF membranes and removal mechanisms are to date poorly understood. The permeate water quality can therefore vary during operation and its decrease would be an undesired outcome for potable water treatment. It is hence important to establish the mechanisms involved in the removal of organic micropollutants by NF membranes in the presence of NOM. In this study, the retention mechanisms of pesticide Endosulfan (ES) in the presence of humic acids (HA) by two NF membranes, TFC-SR2 and TFC-SR3, a "loose" and a "tight" membrane, respectively, were elucidated. The results showed that two mechanisms were involved: (1) the formation of ES-HA complexes (solute-solute interactions), determined from solid-phase micro-extraction (SPME), increased ES retention, and (2) the interactions between HA and the membrane (solute-membrane interactions) increased membrane molecular weight cut-off (MWCO) and decreased ES retention. HA concentration, pH, and the ratio between micropollutant molecular weight (MW) and membrane MWCO were shown to influence ES retention mechanisms. In the absence of HA-membrane interactions at pH 4, an increase of HA concentration increased ES retention from 60% to 80% for the TFC-SR2 and from 80% to 95% for the TFC-SR3 due to ES-HA complex formation. At pH 8, interactions between HA and the loose TFC-SR2 increased the membrane MWCO from 460 to 496 g/mol and ES retention decreased from 55% to 30%, as HA-membrane interactions were the dominant mechanism for ES retention. In contrast, for the "tight" TFC-SR3 membrane the increase in the MWCO (from 165 to 179 g/mol), was not sufficient to decrease ES retention which was dominated by ES-HA interactions. Quantification of the contribution of both solute-solute interactions and solute-membrane interactions is hence fundamental in understanding the removal mechanisms of micropollutant by NF membranes in the presence of NOM in order to optimize the treatment process. PMID:23615337

De Munari, Annalisa; Semiao, Andrea Joana Correia; Antizar-Ladislao, Blanca

2013-04-06

175

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

176

40 CFR 60.462 - Standards for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.462 Section 60.462 Protection of Environment...Coil Surface Coating § 60.462 Standards for volatile organic compounds. (a) On and after the date on which §...

2013-07-01

177

40 CFR 60.492 - Standards for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.492 Section 60.492 Protection of Environment...Surface Coating Industry § 60.492 Standards for volatile organic compounds. On or after the date on which the...

2013-07-01

178

40 CFR 60.602 - Standard for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standard for volatile organic compounds. 60.602 Section 60.602 Protection of Environment...Production Facilities § 60.602 Standard for volatile organic compounds. On and after the date on which the...

2013-07-01

179

40 CFR 60.432 - Standard for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standard for volatile organic compounds. 60.432 Section 60.432 Protection of Environment...Publication Rotogravure Printing § 60.432 Standard for volatile organic compounds. During the period of the performance test...

2013-07-01

180

40 CFR 60.392 - Standards for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.392 Section 60.392 Protection of Environment...Surface Coating Operations § 60.392 Standards for volatile organic compounds. On and after the date on which the...

2013-07-01

181

40 CFR 60.712 - Standards for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.712 Section 60.712 Protection of Environment...Tape Coating Facilities § 60.712 Standards for volatile organic compounds. Each owner or operator of any...

2013-07-01

182

40 CFR 60.452 - Standard for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standard for volatile organic compounds. 60.452 Section 60.452 Protection of Environment...Coating: Large Appliances § 60.452 Standard for volatile organic compounds. On or after the date on which the...

2013-07-01

183

40 CFR 60.742 - Standards for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 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...

2013-07-01

184

40 CFR 60.442 - Standard for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standard for volatile organic compounds. 60.442 Section 60.442 Protection of Environment...Surface Coating Operations § 60.442 Standard for volatile organic compounds. (a) On and after the date on which the...

2013-07-01

185

40 CFR 60.582 - Standard for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standard for volatile organic compounds. 60.582 Section 60.582 Protection of Environment...Urethane Coating and Printing § 60.582 Standard for volatile organic compounds. (a) On and after the date on which the...

2013-07-01

186

40 CFR 60.622 - Standards for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.622 Section 60.622 Protection of Environment...Petroleum Dry Cleaners § 60.622 Standards for volatile organic compounds. (a) Each affected petroleum solvent...

2013-07-01

187

Organic--Inorganic Layer Compounds: Physical Properties and Chemical Reactions  

Microsoft Academic Search

In contrast with intercalation compounds, which can exist both with and without organic molecules between the planes of inorganic material, `molecular composite' compounds have organic groups covalently or ionically bound to inorganic layers. In such crystals the aim is to combine magnetic or optical properties characteristic of the inorganic solid state, like magnetism and luminescence, with properties found in the

P. Day

1985-01-01

188

DYNAMIC ANALYSIS OF SORPTION OF VOLATILE ORGANIC COMPOUNDS IN WATER  

Microsoft Academic Search

Chlorinated and brominated volatile organic compounds are among the groundwater pollutants creating major environmental problems. In this study, dynamic behavior of certain volatile organic compounds in water was investigated by using a novel moment technique. Adsorption equilibrium constant and the penetration length of tracers were evaluated by the first absolute and the second central moment expressions derived for a pulse-response

Nail Yasyerli; Ugur Harbili

2008-01-01

189

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

190

Biorestoration of aquifers contaminated with organic compounds  

Microsoft Academic Search

Several forms of biological treatment can be used to treat contaminated aquifers. In situ treatment increases the activity of the indigenous organisms by the addition of nutrients and electron acceptor. Withdrawal and treatment technologies rely on removal of the ground water and any of several wastewater treatment processes to biodegrade the organics. Addition of acclimated or genetically engineered organisms may

M. D. Lee; J. M. Thomas; R. C. Borden; P. B. Bedient; C. H. Ward; J. T. Wilson; R. A. Conway

1988-01-01

191

Evaluation System for Pesticides (ESPE). 1. Agricultural Pesticides.  

National Technical Information Service (NTIS)

The evaluation system for pesticides (ESPE) is divided in three parts: (1) emission of the pesticide; (2) distribution over and within the different environmental compartments and calculation of exposure concentrations of organisms to the pesticide; (3) h...

H. J. B. Emans M. A. Beek J. B. H. J. Linders

1992-01-01

192

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

PubMed

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 of Agriculture; the Marketplace Surveillance Program of the California Department of Pesticide Regulation; and private tests by the Consumers Union, an independent testing organization. Organically grown foods consistently had about one-third as many residues as conventionally grown foods, and about one-half as many residues as found in IPM/NDR samples. Conventionally grown and IPM/NDR samples were also far more likely to contain multiple pesticide residues than were organically grown samples. Comparison of specific residues on specific crops found that residue concentrations in organic samples were consistently lower than in the other two categories, across all three data sets. The IPM/NDR category, based on data from two of the test programmes, had residues higher than those in organic samples but lower than those in conventionally grown foods. PMID:12028642

Baker, B P; Benbrook, C M; Groth, E; Lutz Benbrook, K

2002-05-01

193

MANIPULATION OF PESTICIDE SORPTION ON SMECTITE CLAY VIA CATION EXCHANGE  

Technology Transfer Automated Retrieval System (TEKTRAN)

Retention of nonpolar organic compounds by soils from aqueous solutions is strongly correlated with soil organic matter content, however, many important categories of pesticides and organic contaminants have polar moieties and recent research has shown that these compounds are strongly adsorbed by s...

194

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

195

New chemically modified polymeric resin for solid-phase extraction of pesticides and phenolic compounds from water.  

PubMed

A new chemically modified polymeric resin, with an o-carboxybenzoyl moiety, is developed to be used in the on-line solid-phase extraction (SPE) of some pesticides and phenolic compounds from aqueous samples, in order to obtain better breakthrough volumes than other commercial sorbents. The chemical introduction of this moiety improves the efficiency of SPE by providing better surface contact with aqueous samples. This synthesized sorbent enables higher volumes of sample to be concentrated for determining polar compounds. When analyzing real samples, tap and river waters, different quantities of sulphite were added to decrease the initial band due to fulvic and humic acids. The matrix peaks decreased and there were no losses in the studied compounds observed when 500 and 1000 microliters of 10% Na2SO3 solution for every 100 ml of sample were added to tap and river water, respectively. PMID:9604330

Masqué, N; Galià, M; Marcé, R M; Borrull, F

1998-04-17

196

Radioiodine Volatilization in the Presence of Organic Compounds  

SciTech Connect

The impact of organic compounds on iodine volatility was investigated under a range of postaccident chemical conditions expected in a reactor containment structure. The rate of production of volatile iodine was evaluated in the presence of 10{sup -3} M concentrations of carbonyl, alkyl halide, and aromatic compounds. A bench-scale apparatus, installed in the irradiation chamber of a Gammacell, was used to measure the rate of iodine volatilization from 10{sup -6} to 10{sup -4} M CsI solutions with pH values from 5 to 9. The results indicated that organic compounds could be classified into groups, based on their distinct effects on iodine volatility. Iodine volatilization increased significantly, up to two orders of magnitude, in the presence of carbonyl compounds and alkyl chlorides, while it decreased in the presence of aromatic compounds. Gas phase speciation indicated that organic iodides dominate the airborne iodine species in the presence of carbonyl compounds and alkyl halides.

Taghipour, Fariborz; Evans, Greg J. [University of Toronto (Canada)

2001-05-15

197

Extended structures and physicochemical properties of uranyl-organic compounds.  

PubMed

The ability of uranium to undergo nuclear fission has been exploited primarily to manufacture nuclear weapons and to generate nuclear power. Outside of its nuclear physics, uranium also exhibits rich chemistry, and it forms various compounds with other elements. Among the uranium-bearing compounds, those with a uranium oxidation state of +6 are most common and a particular structural unit, uranyl UO(2)(2+) is usually involved in these hexavalent uranium compounds. Apart from forming solids with inorganic ions, the uranyl unit also bonds to organic molecules to generate uranyl-organic coordination materials. If appropriate reaction conditions are employed, uranyl-organic extended structures (1-D chains, 2-D layers, and 3-D frameworks) can be obtained. Research on uranyl-organic compounds with extended structures allows for the exploration of their rich structural chemistry, and such studies also point to potential applications such as in materials that could facilitate nuclear waste disposal. In this Account, we describe the structural features of uranyl-organic compounds and efforts to synthesize uranyl-organic compounds with desired structures. We address strategies to construct 3-D uranyl-organic frameworks through rational selection of organic ligands and the incorporation of heteroatoms. The UO(2)(2+) species with inactive U?O double bonds usually form bipyramidal polyhedral structures with ligands coordinated at the equatorial positions, and these polyhedra act as primary building units (PBUs) for the construction of uranyl-organic compounds. The geometry of the uranyl ions and the steric arrangements and functionalities of organic ligands can be exploited in the the design of uranyl--organic extended structures, We also focus on the investigation of the promising physicochemical properties of uranyl-organic compounds. Uranyl-organic materials with an extended structure may exhibit attractive properties, such as photoluminescence, photocatalysis, photocurrent, and photovoltaic responses. In particular, the intriguing, visible-light photocatalytic activities of uranyl-organic compounds are potentially applicable in decomposition of organic pollutants and in water-splitting with the irradiation of solar light. We ascribe the photochemical properties of uranyl-organic compounds to the electronic transitions within the U?O bonds, which may be affected by the presence of organic ligands. PMID:21612214

Wang, Kai-Xue; Chen, Jie-Sheng

2011-05-25

198

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...

199

Early diagenetic alterations of biogenetic organic compounds  

Microsoft Academic Search

Plant matter from a beech forest, leaves, and soil were extracted and analyzed by GC-MS technique. The amount of the extract varies with the CPI value. Characteristic compounds like phytadienes, plant alcohols, polycyclic aromatics, sterols, and triterpenes are observed in different samples at various concentrations. It seems there is a rapid change in the composition of extracts from recent plant

A. Hollerbach; Lehrstuhl ffir Geologie

1978-01-01

200

STUDY DESIGN FOR A PILOT STUDY OF CHILDREN'S TOTAL EXPOSURE TO PERSISTENT PESTICIDES AND OTHER PERSISTENT ORGANIC PESTICIDES "CTEPP"  

EPA Science Inventory

The Children's Total Exposure to Persistent Pesticides and Other Persistent Pollutant (CTEPP) study is one of the largest aggregate exposure studies of young children in the United States. The CTEPP study examines the exposures of about 260 preschool children and their primary ad...

201

BIODEGRADABILITY STUDIES WITH ORGANIC PRIORITY POLLUTANT COMPOUNDS  

EPA Science Inventory

Ninty-six organic priority pollutants (from EPA Effluent Guidelines Consent Decree) were studied to determine the extent and rate of microbial degradation and the acclimation periods needed for substrate biooxidation. The pollutants have been classified into groups with character...

202

[Emission volatile organic compounds from new textile floor coverings].  

PubMed

The emission of formaldehyde and the other volatile organic compounds (toluene, styrene, 4-PC) and total volatile organic compounds (VOCs) from new textile floor coverings was measured with the use of environmental chamber (0.6 m3 capacity) in the following conditions: temperature 23 degrees C, relative humidity 45%, 1 exchange/hour and factor loading 1 m2 m-3. The formaldehyde was determined by using colorimetric method, VOCs by GC method. The tested carpets did not emit formaldehyde. The emission of other volatile organic compounds was very low and fulfill known requirements. PMID:12621886

Igielska, Barbara; Pecka, Irena; Sitko, Elzbieta; Nikel, Grazyna; Wiglusz, Renata

2002-01-01

203

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.

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

2002-01-01

204

The Occurrence and Fate of Organic Micro-Pollutants in a Water Reclaimed for Potable Reuse.  

National Technical Information Service (NTIS)

The occurrence of toxic compounds such as chlorinated pesticides, organophosphate pesticides, polynuclear aromatic hydrocarbons, volatile halogenated hydrocarbons and organic material in the feed and the final water produced by the Stander reclamation pla...

J. F. J. Vanrensburg P. G. Vanrossum W. H. J. Hattingh

1977-01-01

205

Organic Compounds in Truckee River Water Used for Public Supply near Reno, Nevada, 2002-05  

USGS Publications Warehouse

Organic compounds studied in this U.S. Geological Survey (USGS) assessment generally are man-made, including, in part, pesticides, solvents, gasoline hydrocarbons, personal care and domestic-use products, and refrigerants and propellants. Of 258 compounds measured, 28 were detected in at least 1 source water sample collected approximately monthly during 2002-05 at the intake of the Chalk Bluff Treatment Plant, on the Truckee River upstream of Reno, Nevada. The diversity of compounds detected indicate various sources and uses (including wastewater discharge, industrial, agricultural, domestic, and others) and different pathways (including point sources from treated wastewater outfalls upstream of the sampling location, overland runoff, and groundwater discharge) to drinking-water supply intakes. Three compounds were detected in more than 20 percent of the source-water intake samples at low concentrations (less than 0.1 microgram per liter), including caffeine, p-cresol (a wood preservative), and toluene (a gasoline hydrocarbon). Sixteen of the 28 compounds detected in source water also were detected in finished water (after treatment, but prior to distribution; 2004-05). Additionally, two disinfection by-products not detected in source water, bromodichloromethane and dibromochloromethane, were detected in all finished water samples. Two detected compounds, cholesterol and 3-beta-coprostanol, are among five naturally occurring biochemicals analyzed in this study. 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 compounds. Seven compounds (toluene, chloroform, bromodichloromethane, dibromodichloromethane, bisphenol A, cholesterol, and 3-beta-coprostanol) were measured at concentrations greater than 0.1 microgram per liter. On the basis of this screening-level assessment, adverse effects to human health are expected to be negligible (subject to limitations of available human-health benchmarks).

Thomas, Karen A.

2009-01-01

206

Natural production of organic bromine compounds in Berlin Lakes.  

PubMed

Berlin surface waters are characterized by elevated concentrations of organic bound bromine (up to 35 microg/L) in late summer. Organic bromine compounds in lakes are of significant importance because human life is closely connected to fresh water. Apart from recreational use, fresh water is frequently used for the production of drinking water, e.g., after bank filtration. Therefore the source, particularly the mechanism responsible for the formation is studied. Field studies indicate that the organic bromine compounds, measured as adsorbable organic bromine (AOBr), are autochthonous. Staggered maxima concentrations of chlorophyll-a, DOC and AOBr indicate that phototrophic organisms might contribute to the AOBr after death. The involvement of phototrophic organisms was established in the laboratory using surface water and/or cultures of organisms. Light and the presence of phototrophic organisms are essential for an AOBr production. Phototrophic organisms incorporate bromide, which is released randomly and after cell death. A part of the incorporated bromide is used for the formation of organic bromine compounds in the cell. After death of the organisms the brominated compounds and the incorporated bromide are released into the water phase, and an extracellular AOBr production can lead to a further formation of AOBr, most probably due to the parallel release of haloperoxidases. PMID:17547185

Hütteroth, Alexandra; Putschew, Anke; Jekel, Martin

2007-05-15

207

Adsorption of organic compounds pertinent to urban environments onto mineral dust particles  

NASA Astrophysics Data System (ADS)

The interaction of mineral dust particles from the Sahara with semivolatile organic compounds over an urban region in Israel's coastal plain was studied. Dust samples were collected during numerous dust storm events in 2000 and 2001, under varying meteorological conditions. Organic compounds adsorbed on collected mineral dust particles were analyzed using an integrated, multitechnique study that employed a scanning electron microscope equipped with an energy dispersion system (SEM-EDS) and bulk aerosol analysis by gas chromatography/mass spectrometry (GC/MS) and ion chromatography (IC). The SEM-EDS analysis exemplifies the coexistence of inorganic and organic species on individual mineral dust particles. Using the GC/MS and IC analysis, specific tracers for urban air pollution and photodegradation products of agriculture emissions have been identified, and their size distributions have been obtained. Redistribution of semivolatile organics such as polycyclic aromatic hydrocarbons (PAH) and pesticides from submicron to larger particle size fractions, governed by the mineral dust transport trajectory and size distributions, was observed. Nonvolatile species, such as anhydrous sugars and large PAH, do not redistribute between the phases because of their low vapor pressure. The concentrations of short chain carboxylic acids increased with higher ambient relative humidity, suggesting water-assisted uptake onto the mineral particles.

Falkovich, Alla H.; Schkolnik, Gal; Ganor, Eliezer; Rudich, Yinon

2004-01-01

208

Concentration of Organic Compounds in Water. A Literature Survey.  

National Technical Information Service (NTIS)

Because of the large variety of chemical compounds present either naturally or as industrial contaminants in water samples, no single concentration method currently available is adequate for concentrating all organics in the water sample. Consequently, in...

R. L. Jolley

1980-01-01

209

MEASUREMENT OF VAPOR PHASE ORGANIC COMPOUNDS AT HIGH CONCENTRATIONS  

EPA Science Inventory

Laboratory, industrial, chemical, or other waste products may have constituents that evolve volatile organic compounds (VOCS) at very high concentrations. hese could pose human health risks during handling, storage, and disposal of the waste through inhalation, dermal exposure, o...

210

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...

211

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 ...

212

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...

213

TREATABILITY OF CARCINOGENIC AND OTHER HAZARDOUS ORGANIC COMPOUNDS  

EPA Science Inventory

This research program was conducted to determine the capability of biological and physical-chemical treatment processes to remove chemical carcinogens and other hazardous organic compounds from water and wastewater. Treatment processes investigated included biological degradation...

214

DEVELOPMENT OF OZONE REACTIVITY SCALES FOR VOLATILE ORGANIC COMPOUNDS  

EPA Science Inventory

Methods for developing a numerical scale ranking reactivities of volatile organic compounds (VOCs) towards ozone formation were investigated. ffects of small VOC additions on ozone formation (incremental reactivities) were calculated for 140 types of VOCs in model scenarios repre...

215

METHODS FOR LEVEL 2 ANALYSIS BY ORGANIC COMPOUND CATEGORY  

EPA Science Inventory

The report gives Level 2 procedures, including results of a laboratory evaluation of detailed methods for analyzing organic chemicals in particular compound categories. The report, supplementing an earlier Level 2 procedures manual, provides an initial experimental data base as a...

216

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...

217

Collaborative Study of Soils Spiked with Volatile Organic Compounds.  

National Technical Information Service (NTIS)

Vapor fortification is a method of spiking soils with volatile organic compounds (VOCs) that was recently developed for producing materials suitable for performance evaluation and quality assurance/quality control (QA/QC). Using this treatment method, soi...

A. D. Hewitt C. L. Grant

1995-01-01

218

COMPACT, CONTINUOUS MONITORING FOR VOLATILE ORGANIC COMPOUNDS - PHASE I  

EPA Science Inventory

Improved methods for onsite measurement of multiple volatile organic compounds are needed for process control, monitoring, and remediation. This Phase I SBIR project sets forth an optical measurement method that meets these needs. The proposed approach provides an instantaneous m...

219

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

220

Natural organic matter (NOM) and pesticides removal using a combination of ion exchange resin and powdered activated carbon (PAC).  

PubMed

The combination of anion exchange resins (AERs) and powdered activated carbon (PAC) was studied to remove both natural organic matter (NOM) and pesticides. Experiments were conducted with high dissolved organic carbon (DOC) surface water (about 6.0mg DOC/L) spiked with both atrazine and isoproturon. AERs, like MIEX and IRA938, showed up to 75% removal of DOC after 30min contact time. The addition of PAC after treatment with these AERs only slightly decreased the residual DOC from 1.4 to 1.2mg/L. Experiments conducted with high (200microg/L) and low (1microg/L) initial pesticide concentrations showed that simultaneous and successive combinations of AER and PAC significantly improve the removal of both pesticides compared with PAC treatment on raw water. The improvement of short-term adsorption kinetics was explained by the adsorption of pesticides on AERs (about 5%) and the removal of high molecular weight (MW) NOM structures by AERs that reduce pore blockage phenomena. For 24h contact time with PAC (adsorption isotherms), the benefit of AER treatment was lower, which indicates that the refractory DOC to AER treatment still competes through direct site competition mechanism. MIEX resin had a distinct behavior since the simultaneous treatment with PAC showed no benefit on pesticide adsorption. The presence of fine residues of MIEX was shown to interfere with PAC adsorption. PMID:18006038

Humbert, Hugues; Gallard, Hervé; Suty, Hervé; Croué, Jean-Philippe

2007-10-15

221

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...

222

DESTRUCTION OF VOLATILE ORGANIC COMPOUNDS VIA CATALYTIC INCINERATION  

EPA Science Inventory

The paper gives results of an investigation of the effect of catalytic incinerator design and operation the destruction of specific volatile organic compounds (VOCs), both singly and in mixtures. A range of operating and design parameters were tested on a wide variety of compound...

223

MASS SPECTRA OF SOME ORGANIC AND INORGANIC COMPOUNDS  

Microsoft Academic Search

A compilation was made of some mass spectra of various organic and ; inorganic compounds which are not listed in previous compilations of mass ; spectral data. These compounds were collected from various sources, and many are ; the result of syntheses in the University of California Chemistry Department or ; the Lawrence Radiation Laboratory. All have appreciable vapor pressures

A. S. Newton; S. J. Waters

1959-01-01

224

Radiocarbon dating of diatom-bound organic compounds  

Microsoft Academic Search

Here we present a new method for obtaining radiocarbon dates for the organic compounds intrinsic to diatom frustules. This method will improve age models for sediment cores that lack calcium carbonate and improve current interpretations of diatom-based paleoproxies. In preparation for radiocarbon dating by Accelerator Mass Spectrometry, compounds intrinsic to diatom frustules are released from their opal matrix by dissolution

Anitra E. Ingalls; Robert F. Anderson; Ann Pearson

2004-01-01

225

Octanol-Water Partition Coefficients of Simple Organic Compounds  

Microsoft Academic Search

Octanol-water partition coefficients (log P) for 611 simple organic compounds representing all principal classes have been retrieved from the literature. Available experimental details of measurement are documented from original articles. Pertinent thermodynamic relations are presented, with a discussion of direct and indirect methods of measurement. Reported log P data for each compound have been evaluated according to stated criteria, and

James Sangster

1989-01-01

226

Novel Organic-Inorganic Hybrid Compounds Containing Alkyldiammonium Salts  

Microsoft Academic Search

Novel organic-inorganic hybrid compounds, C n N 2 PbBr 4 (n=4,6,8 and 10) and C 2 N 2 PbBr 4 · DMSO, were prepared by the self-organization of lead bromide and a variety of alkyldiammonium cations. The powder X-ray diffraction patterns of C n N 2 PbBr 4 demonstrated that the compounds form layered perovskite structures and the interlayer spacing

Takashi Matsui; Mitsuyasu Kawahara; Kenjiro Teshima; Masahiro Rikukawa; Kohei Sanui

2002-01-01

227

Effect of organic fertilizers derived dissolved organic matter on pesticide sorption and leaching  

Microsoft Academic Search

Incorporation of organic fertilizers\\/amendments has been, and continues to be, a popular strategy for golf course turfgrass management. Dissolved organic matter (DOM) derived from these organic materials may, however, facilitate organic chemical movement through soils. A batch equilibrium technique was used to evaluate the effects of organic fertilizer-derived DOM on sorption of three organic chemicals (2,4-D, naphthalene and chlorpyrifos) in

Kun Li; Baoshan Xing; William A. Torello

2005-01-01

228

Pesticides and cancer  

Microsoft Academic Search

Epidemiologic evidence on the relationship between chemical pesticides and cancer is reviewed. In animal studies, many pesticides are carcinogenic, (e.g., organochlorines, creosote, and sulfallate) while others (notably, the organochlorines DDT, chlordane, and lindane) are tumor promoters. Some contaminants in commercial pesticide formulations also may pose a carcinogenic risk. In humans, arsenic compounds and insecticides used occupationally have been classified as

Jan Dich; Shelia Hoar Zahm; Annika Hanberg; Hans-Olov Adami

1997-01-01

229

Determination of pesticide residues in Turkey’s table grapes: the effect of integrated pest management, organic farming, and conventional farming  

Microsoft Academic Search

Turkey is one of the world’s largest producers and exporters of table grapes. Growing social concerns over excessive pesticide\\u000a use have led to farming to move from conventional to organic practices. Table grapes were collected from 99 different farms\\u000a in three Aegean regions. Pesticide residues were only detected in farms using conventional agriculture practices while no\\u000a pesticides were detected in

Cafer Turgut; Hakan Ornek; Teresa J. Cutright

2011-01-01

230

(Pesticide chemistry)  

SciTech Connect

This report summarizes a trip by L. W. Barnthouse of the Environmental Sciences Division (ESD), Oak Ridge National Laboratory (ORNL), to Hamburg, Federal Republic of Germany (FRG), where he participated in the 7th International Congress of Pesticide Chemistry. He chaired a workshop on experimental systems for determining effects of pesticides on nontarget organisms and gave an oral presentation at a symposium on pesticide risk assessment. Before returning to the United States, Dr. Barnthouse visited the Netherlands Institute for Sea Research in Texel, the Netherlands.

Barnthouse, L.W.

1990-09-04

231

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

232

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

233

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 ...

234

Organic sulfur compounds in crude oils of West Kazakhstan  

Microsoft Academic Search

This article reports on a study of the distribution of organic sulfur compounds (mercaptans, disulfides, and sulfides) in crude oils and in 50°C cuts, and also in gas condensates. Notes that the crude oils of West Kazakhstan, particularly the field that have been discovered recently, are extremely diverse in physiochemical properties, particularly in their content and structure of organic sulfur

V. V. Ryzhenko; N. S. Buyanova; A. V. Kotova; N. K. Nadirov

1983-01-01

235

INTERACTIONS BETWEEN ORGANIC COMPOUNDS AND CYCLODEXTRIN-CLAY SYSTEMS  

EPA Science Inventory

Computational and experimental techniques are combined in order to better understand interactions involving organic compounds and cyclodextrin (CD)-clay systems. CD-clay systems may have great potential in the containment of organic contaminants in the environment. This study w...

236

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...

237

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....

238

[Methods for the assessment of organic compounds biodegradability: A review].  

PubMed

There are plenty of methods used for the assessment of organic compounds biodegradability, but lack of comprehensive literatures in systematically introducing the assessment methods and guiding the choice of the methods. This paper briefly introduced the indicative parameters in assessing organic compounds biodegradability and the assessment methods of aerobic and anaerobic biodegradation, with the focus on the principles and criteria in the choice of the assessment methods, and analyzed in detail the reasons for the differences in the biodegradation rates of organic compounds when different test methods were adopted. Taking the standards established by the Organization for Economic Co-operation and Development (OECD) as an example, the process of choosing and applying the assessment methods was introduced, the systematic method-choosing route was integrated, and the advantages of the OECD standard methods were pointed out. PMID:23705410

Lu, Kang; Yang, Shang-Yuan; Liang, Zhi-Wei; Wang, Yun-Long; Li, Xin; Yu, Hua-Dong; Wu, Wei-Xiang

2013-02-01

239

Thermal decomposition studies of halogenated organic compounds  

SciTech Connect

Thermal decomposition results for CCl{sub 4}, CHCl{sub 3}, CH{sub 2}Cl{sub 2}, CH{sub 3}Cl, C{sub 3}H{sub 3}Cl, CFCl{sub 3}, CF{sub 2}Cl{sub 2}, CF{sub 3}Cl, CF{sub 2}HCl, CF{sub 3}I, CH{sub 3}I, C{sub 2}H{sub 5}I, C{sub 6}H{sub 5}I, and CCl{sub 2}O are presented. The results were obtained by shock tube techniques coupled with optical spectroscopic detection of transient species formed from dissociation. The method is illustrated with the CH{sub 3}I (+ Kr) {yields} CH{sub 3} + I (+ Kr) reaction where decomposition was monitored using I-atomic resonance absorption spectrometry (ARAS). Modern unimolecular rate theoretical analysis has been carried out on the present cases, and the conclusions from these calculations are discussed. Lastly, the possible destruction of halo-organics by incineration is considered and some implications are discussed.

Michael, J.V.; Kumaran, S.S.

1997-06-01

240

Pesticide runoff from greenhouse production.  

PubMed

A research has been undertaken studying pesticide residues in water from greenhouses and the use of soils and filter materials to reduce such losses. The pesticides detected in water samples collected downstream greenhouses include 9 fungicides, 5 herbicides and 4 insecticides. 10 compounds from flower and vegetable productions were frequently found to exceed environmental risk levels, and with a few exceptions the compounds were found in higher concentrations than those typically found in agricultural runoff. Some compounds were found in high concentrations (>1 microg/l) in undiluted runoff from greenhouses producing vegetables. Nutrient concentrations in the runoff were also sporadically very high, with phosphorous values varying between 0.85 and 7.4 mg P/l, and nitrogen values between 7.5 and 41.4 mg N/l. Undiluted runoff from the productions showed values of 60 mg P/l and 300 mg N/l. High values of pesticides correlated with high values of nutrients, especially P. Column experiments using a sandy agricultural soil and stock solutions of non-polar and slightly polar pesticides mixed with a complex binder and nutrients showed a significant reduction for nearly all of the compounds used, indicating that transport through soil will reduce the concentrations of the studied pesticides. The pesticide adsorption capacity of the filter materials pine bark, peat, Sphagnum moss, compost, oat straw, ferrous sand and clay soil were tested in batch and column experiments. Adsorption were studied contacting the filter materials with aqueous solutions containing greenhouse production pesticides. The batch experiments showed that pine bark and peat, both combining a high content of organic matter with a low ph, provided the highest adsorption for most of the tested pesticides. Sphagnum moss, compost and oat straw also showed high adsorption for most of the pesticides, while the mineral filters provided the lowest adsorption (30-55%). Further column experiments confirmed these results, displaying the best removal efficiency in the organic materials, varying from 200 microg/g in compost, to 500 microg/g in moss, straw and pine bark. PMID:20351415

Roseth, Roger; Haarstad, Ketil

2010-01-01

241

Current-Use Pesticides and Organochlorine Compounds in Precipitation and Lake Sediment from Two High-Elevation National Parks  

NASA Astrophysics Data System (ADS)

Current-use pesticides (CUPs) and banned organochlorine compounds (OCCs) were measured in precipitation and lake sediments from two national parks in the Western U.S. to determine their occurrence and distribution in high-elevation environments. CUPs frequently detected in snow were endosulfan, dacthal, and chlorothalonil in concentrations ranging from 0.07 to 2.4 ng/L. Of the OCCs, only chlordane, HCB, and two PCB congeners were detected. Pesticides most frequently detected in rain were atrazine, carbaryl, and dacthal in concentrations from 3.0 to 95 ng/L. Estimated annual deposition rates in one of the parks were 8.4 ?g/m2 for atrazine, 9.9 ?g/m2 for carbaryl, and 2.6 ?g/m2 for dacthal of which over 85% occurred during summer. DDE and DDD were the most frequently detected OCCs in lake sediments. DDD and DDE concentrations in an age dated sediment core suggest that atmospheric deposition of banned OCCs, to high-elevation areas have been in decline since the 1970s. Dacthal and endosulfan sulfate were present in low concentrations (0.11-1.2 ?g/kg) and were the only CUPs detected in lake sediments.

Mast, M. A.; Foreman, W. T.

2007-12-01

242

77 FR 46961 - Approval and Promulgation of Implementation Plans; Wisconsin; Volatile Organic Compound Emission...  

Federal Register 2010, 2011, 2012, 2013

...Implementation Plans; Wisconsin; Volatile Organic Compound Emission Control Measures for...Technology (RACT) for sources of Volatile Organic Compound (VOC) emissions in moderate...recordkeeping requirements, Volatile organic compounds. Dated: June 11, 2012....

2012-08-07

243

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

244

Derivatives of phenyl tribromomethyl sulfone as novel compounds with potential pesticidal activity.  

PubMed

A halogenmethylsulfonyl moiety is incorporated in numerous active herbicides and fungicides. The synthesis of tribromomethyl phenyl sulfone derivatives as novel potential pesticides is reported. The title sulfone was obtained by following three different synthetic routes, starting from 4-chlorothiophenol or 4-halogenphenyl methyl sulfone. Products of its subsequent nitration were subjected to the S(N)Ar reactions with ammonia, amines, hydrazines and phenolates to give 2-nitroaniline, 2-nitrophenylhydrazine and diphenyl ether derivatives. Reduction of the nitro group of 4-tribromomethylsulfonyl-2-nitroaniline yielded the corresponding o-phenylenediamine substrate for preparation of structurally varied benzimidazoles. PMID:22423293

Borys, Krzysztof M; Korzy?ski, Maciej D; Ochal, Zbigniew

2012-02-15

245

Volatile organic compounds in Gulf of Mexico sediments  

SciTech Connect

Volatile organic compounds (VOC), concentrations and compositions were documented for estuarine, coastal, shelf, slope, and deep water sediments from the Gulf of Mexico. VOC were measured (detection limit >0.01 ppb) using a closed-loop stripping apparatus with gas chromatography (GC) and flame ionization, flame photometric, and mass spectrometric detectors. The five primary sources of Gulf of Mexico sediment VOC are: (1) planktonic and benthic fauna and flora; (2) terrestrial material from riverine and atmospheric deposition; (3) anthropogenic inputs: (4) upward migration of hydrocarbons; and (5) transport by bottom currents or slumping. Detected organo-sulfur compounds include alkylated sulfides, thiophene, alkylated thiophenes, and benzothiophenes. Benzothiophenes are petroleum related. Low molecular weight organo-sulfur compounds result from the biological oxidation of organic matter. A lack of organosulfur compounds in the reducing environment of the Orca Basin may result from a lack of free sulfides which are necessary for their production.

McDonald, T.J.

1988-01-01

246

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

2007-05-09

247

Photosynthetic marine organisms as a source of anticancer compounds  

Microsoft Academic Search

Since early human history, plants have served as the most important source of medicinal natural products, and even in the\\u000a “synthetic age” the majority of lead compounds for pharmaceutical development remain of plant origin. In the marine realm,\\u000a algae and seagrasses were amongst the first organisms investigated by marine natural products scientists on their quest for\\u000a novel pharmaceutical compounds. Forty

F. Folmer; M. Jaspars; M. Dicato; M. Diederich

2010-01-01

248

Adsorption Selectivity of FSM-16 for Several Organic Compounds  

Microsoft Academic Search

A folded-sheet mesoporous material (FSM-16) was prepared, and its adsorption selectivity for several organic compounds (p-nitrophenol, toluene, n-heptane, benzene, cyclohexane, and o-dichlorobenzene) was studied. The adsorbed amounts of these compounds were measured by batch operation in liquid phase. The p-nitrophenol in aqueous solution was hardly adsorbed into FSM-16, but toluene (in n-heptane solvent) and benzene (in n-heptane solvent or cyclohexane

Masahiro Katoh; Hitoshi Takao; Naoto Abe; Tahei Tomida

2001-01-01

249

Transformation of certain organic compounds on exhaustive oxidation catalysts  

Microsoft Academic Search

The authors studied the role of water in vapor-phase catalytic oxidation. Two catalysts and three organic compounds of different chemical natures - formic acid, 4,4-dimethyl-1,3-dioxane, and isopropanol - were used as examples, and it was shown that water vapor does not hinder the vapor-phase transformations of these compounds at the intermediate stages of exhaustive catalytic oxidation during dehydrogenation and dehydration.

E. V. Kuznetsova; S. V. Zubarev; V. V. Ivanova; L. N. Karazeeva; S. A. Taranenko

1988-01-01

250

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

251

Pesticides in the environment  

NASA Astrophysics Data System (ADS)

The most important studies on the behaviour of six classes of pesticides in objects within the environment are described systematically and discussed. General schemes for the metabolism of certain pesticides in animal organisms, plants, and the soil are presented. The principal requirements which must be met by modern pesticides and the conditions for their safe use are characterised. The bibliography includes 250 references.

Mel'nikov, N. N.

1992-10-01

252

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

253

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.

254

Bioconcentration factors for volatile organic compounds in vegetation.  

PubMed

Samples of air and leaves were taken at the University of Nevada [Formula: see text] 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 compounds (VOCs) and to characterize the equilibration of VOCs between the leaves and air. The bioconcentration of volatiles in the leaves of some species can be predicted using the partition coefficients between air and octanol (K(oa)) and only considering VOC absorption in the lipid fraction of leaves. For these leaves, the bioconcentration factors agreed with existing models. Leaves of some species displayed a bioconcentration of volatiles that greatly exceeded theory. These hyperbioconcentration leaves also contain appreciable concentrations of monoterpenes, suggesting that a terpenoid compartment should be considered for the bioconcentration of organic compounds in leaves. Adding an additional "terpenoid" compartment should improve the characterization of volatile organic compounds in the environment. The uptake of VOCs from air by leaves is rapid, and the equilibration rates are seen to be quicker for compounds that have higher vapor pressures. The release of VOCs from the leaves of plants is slower for hyperbioconcentration leaves. PMID:21644617

Hiatt, M H

1998-03-01

255

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

256

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

Microsoft Academic Search

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

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

2008-01-01

257

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

258

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

259

Comparison of organochlorine pesticides and polychlorinated biphenyls residues in vegetables, grain and soil from organic and conventional farming in Poland.  

PubMed

Organic and conventional crops were studied by identifying the relationship between persistent organic pollutants in cereals, vegetables and soil. The residues of organochlorine pesticides and polychlorinated biphenyls (PCBs) were determined in grains (rye and wheat), vegetables (carrots and beets) and soil collected from the fields. PCB residues recorded in the beets from organic farming were as high as 3.71 ppb dry weight (dry wt.), while in the soil from conventional farming of beets 0.53 ppb dry wt. Among vegetables, higher concentrations of pesticides were detected in organically grown beets (190.63 ppb dry wt.). Soil samples from the organic farming contained lower levels of organochlorine pesticide residues compared to the conventional farming. Taking into account toxicity equivalent (TEQ), the conventionally grown carrots accumulated the most toxic PCBs. Non-ortho and mono-ortho PCBs were also noted in the grain of conventionally grown rye and amounted to 3.05 pg-TEQ/g wet wt. PMID:22428896

Witczak, Agata; Abdel-Gawad, Hassan

2012-01-01

260

Raman scattering studies of organic semiconducting charge-transfer compounds  

NASA Astrophysics Data System (ADS)

Organic semiconductors offer the possibility of devices with greater mechanical flexibility and lower production costs compared to existing materials. Reports of carrier mobilities in monomolecular organic semiconductors in the 10-50 cm^2/V-s range and success in fabricating electronic devices from organic materials has increased the interest in their properties for electronic applications. However, the range of properties displayed by the monomolecular crystals is rather narrow. Charge-transfer compounds composed of two different organic molecules in which one acts as a donor and the other as an acceptor may represent the next generation of organic semiconductors. Control of their properties by modification of the molecules or changes in stoichiometry and crystalline structure makes them particularly attractive for a wide range of applications provided that the relationship between the structure and constituents of the compounds and their physical properties can be elucidated. Raman scattering studies of single crystals of two representative charge-transfer compounds, perylene-TCNQ and anthracene-TCNQ, will be presented. Theoretical calculations suggest that these materials have the potential for ambipolar charge transport, and so intermolecular interactions in these compounds are of particular interest.

McNeil, Laurie; Kloc, Christian

2011-03-01

261

Gas chromatographic determination of water in organic compounds and of organic compounds in water after steam distillation  

SciTech Connect

A gas chromatograph (GC) with a flame ionization detector (FID) is shown to be effective in the determination of water in organic compounds. The ketal, 2,2-dimethoxypropane (DMP), reacts quantitatively with water to yield the products methanol and acetone when an acid catalyst is present. A solid acid catalyst, Nafion, has been effective and is easily separated before sample introduction into the GC. Several organic solvents were analyzed using this indirect method for determining water. The method is effective for determining water from 0.001-3.5% w/w. Solid samples were also analyzed and the water found in additional spikes agreed with the amount added. Simple steam distillation is used for the isolation and concentration of organic compounds from water matrices. Organic compounds are spiked into a flask containing water and the mixture is then boiled. Typical distillation times take less than 25 minutes. The condensate is collected in a small collection tube and a portion is injected into a GC containing a capillary column. The recovery of most compounds with boiling points from 77 to 238{degree}C is better than 90% and a concentration effect of ten is realized. Steam distillation combined with solid phase extraction is shown to be effective in isolating and concentrating compounds from water in the part-per-billion range. A simple interface between the boiling apparatus and resin collection column is presented. Once the organic analytes are boiled and collected on the resin, they are removed with a small amount of ethyl acetate. The ethyl acetate solution is then injected into a GC. Compounds with boiling points above 400{degree}C can be determined by turning off the flow of cold water in the condenser. Recoveries are better than 80% for compounds with boiling points between 132 to 404{degree}C.

Dix, K.D.

1989-01-01

262

Partition of Volatile Organic Compounds in Activated Sludge and Wastewater  

Microsoft Academic Search

The Henry’s law constant is important in the gas-liquid mass transfer process. Apparent dimensionless Henry’s law constant, or the gas-liquid partition coefficient (K’H), for both hydrophilic (methanol, isopropyl alcohol, and acetone) and hydrophobic (toluene and p-xylene) organic compounds in deionized (DI) water, a wastewater with a maximum total dissolved organic carbon (DOC) content of 700 mg\\/L, and DI water mixed

Jun-Hong Lin; Ming-Shean Chou

2006-01-01

263

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.

Damalas, Christos A.; Eleftherohorinos, Ilias G.

2011-01-01

264

REMOVAL OF PESTICIDES FROM WATER BY BIOMOLECULE-EXCHANGED CLAYS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Replacement of natural inorganic cations of clay minerals with organic cations through ion exchange reactions has been proposed as an strategy to improve the adsorptive capacity of clay minerals for organic compounds, including pesticides. The organic cations most commonly used for this purpose have...

265

VOC (VOLATILE ORGANIC COMPOUND) FUGITIVE EMISSION PREDICTIVE MODEL - USER'S GUIDE  

EPA Science Inventory

The report discusses a mathematical model that can be used to evaluate the effectiveness of various leak detection and repair (LDAR) programs on controlling volatile organic compound (VOC) fugitive emissions from chemical, petroleum, and other process units. The report also descr...

266

PHOTOTHERMAL DESTRUCTION OF THE VAPOR OF VOLATILE ORGANIC COMPOUNDS  

EPA Science Inventory

The contamination of subsurface soil and groundwater by volatile organic compounds (VOCS) is a pervasive problem in the United States. n-situ soil vapor extraction (SVE) and ex-situ thermal desorption are the most adapted technologies for the remediation of contaminated soil whil...

267

Volatile organic compound emissions from dairy facilities in central California  

Technology Transfer Automated Retrieval System (TEKTRAN)

Emissions of volatile organic compounds (VOCs) from dairy facilities are thought to be an important contributor to high ozone levels in central California, but emissions inventories from these sources contain significant uncertainties. In this work, VOC emissions were measured at two central Califor...

268

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...

269

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...

270

LEAVES AS INDICATORS OF EXPOSURE TO AIRBORNE VOLATILE ORGANIC COMPOUNDS  

EPA Science Inventory

The concentration of volatile organic compounds (VOCs) in leaves is primarily a product of airborne exposures and dependent upon bioconcentration factors and release rates. The bioconcentration factors for VOCs in grass are found to be related to their partitioning between octan...

271

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...

272

Volatile organic compounds in some urban locations in United States  

Microsoft Academic Search

Volatile organic compounds (VOCs) have been determined to be human risk factors in urban environments, as well as primary contributors to the formation of photochemical oxidants. Ambient air quality measurements of 54 VOCs including hydrocarbons, halogenated hydrocarbons and carbonyls were conducted in or near 13 urban locations in the United States during September 1996 to August 1997. Air samples were

Mahmoud F. Mohamed; Daiwen Kang; Viney P. Aneja

2002-01-01

273

Assessment of volatile organic compound emissions from ecosystems of China  

Microsoft Academic Search

Isoprene, monoterpene, and other volatile organic compound (VOC) emissions from grasslands, shrublands, forests, and peatlands in China were characterized to estimate their regional magnitudes and to compare these emissions with those from landscapes of North America, Europe, and Africa. Ecological and VOC emission sampling was conducted at 52 sites centered in and around major research stations located in seven different

L. F. Klinger; Q.-J. Li; A. B. Guenther; J. P. Greenberg; B. Baker; J.-H. Bai

2002-01-01

274

Removal of Volatile Organic Compounds from polluted air  

Microsoft Academic Search

Volatile Organic Compounds (VOCs) are among the most common air pollutants emitted from chemical, petrochemical, and allied industries. VOCs are one of the main sources of photochemical reaction in the atmosphere leading to various environmental hazards; on the other hand, these VOCs have good commercial value. Growing environmental awareness has put up stringent regulations to control the VOCs emissions. In

Faisal I. Khan; Aloke Kr. Ghoshal

2000-01-01

275

DESTRUCTION OF VOLATILE ORGANIC COMPOUNDS VIA CATALYTIC INCINERATION (JOURNAL VERSION)  

EPA Science Inventory

The paper gives results of an investigation of the effect of catalytic incinerator design and operation on the destruction of specific volatile organic compounds (VOCs), both singly and in mixtures. A range of operating and design parameters were tested on a wide variety of compo...

276

Organic Compounds in Coal-Slurry-Pipeline Waters. Final Report.  

National Technical Information Service (NTIS)

Organic compounds in the water separated from coal pipeline slurry has been investigated on a laboratory basis for the slurry with each of three subbituminous coals: Wyodak, Illinois No. 6 and Black Mesa. The results are compare with results from the Blac...

A. S. Newton H. Villarreal P. J. Fox R. Raval W. Walker

1982-01-01

277

Mass transfer of nonvolatile organic compounds from porous media  

Microsoft Academic Search

This thesis presents data pertaining to the mass transfer of nonvolatile organic compounds from porous media. Physical properties of porous solids, including surface and pore areas, are studied. Information from these studies, along with dissolution data, are used to develop correlations relating the Sherwood Number to the Peclet Number. The contaminant used in this study is naphthalene; the solids used

Crist Simon Khachikian

1999-01-01

278

FIELD EXPERIENCE WITH FOUR PORTABLE VOC (VOLATILE ORGANIC COMPOUND) MONITORS  

EPA Science Inventory

This report discusses the field operation problems associated with use of four portable volatile organic compound (VOC) detection instruments in conducting Reference Method 21 VOC screenings. The report presents the results of the field trials and summarizes the ease of use of ea...

279

Synthesis of tritium-labeled nitrogen-containing organic compounds  

SciTech Connect

Conditions of tritium labeling of certain nitrogen-containing organic compounds have been determined. Combination of isotope exchange or hydrogenation with gaseous tritium and chemical synthesis allowed preparation of N-oleyldihydrosphingosine (I) and spermine with molar radioactivities of 200-210 and 23-25 Ci mmol{sup {minus}1} respectively.

Shevchenko, V.P.; Nagaev, I.Yu.; Potapova, A.V. [Inst. of Molecular Genetics, Moscow (Russian Federation)] [and others

1995-07-01

280

In situ bioremediation of petroleum hydrocarbon and other organic compounds  

Microsoft Academic Search

From supertanker oil spills to the leaking underground storage tank at the corner gas station, contamination from petroleum hydrocarbon fuels and other organic compounds is an environmental concern that affects nearly every small hamlet and major metropolis throughout the world. Moreover, the world`s rivers, estuaries, and oceans are threatened by contamination from petroleum leaks and spills. Fortunately, most petroleum hydrocarbons

B. C. Alleman; A. Leeson

1999-01-01

281

Volatile organic compound emission factors from roadside measurements  

Microsoft Academic Search

Volatile organic compounds (VOCs) play a significant role in the generation of urban photochemical smog. In addition, some VOCs, such as benzene, are harmful to human health. In Japan, motor vehicles are the dominant source of VOCs. Therefore, it is important to determine the emission of VOCs from vehicles in order to estimate human risk and the production mechanisms of

Hiroto Kawashima; Shigeki Minami; Yoshimichi Hanai; Akihiro Fushimi

2006-01-01

282

Qualitative analysis of volatile organic compounds on biochar  

Technology Transfer Automated Retrieval System (TEKTRAN)

Qualitative identification of sorbed volatile organic compounds (VOCs) on biochar was conducted by headspace thermal desorption coupled to capillary gas chromatographic-mass spectrometry. VOCs may have a mechanistic role influencing plant and microbial responses to biochar amendments, since VOCs ca...

283

Modeling emissions of volatile organic compounds from silage  

Technology Transfer Automated Retrieval System (TEKTRAN)

Volatile organic compounds (VOCs), necessary reactants for photochemical smog formation, are emitted from numerous sources. Limited available data suggest that dairy farms emit VOCs with cattle feed, primarily silage, being the primary source. Process-based models of VOC transfer within and from si...

284

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

Microsoft Academic Search

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

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

2002-01-01

285

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

2013-01-23

286

DETERMINING ACTIVE OXIDANT SPECIES REACTING WITH ORGANOPHOSPHATE PESTICIDES IN CHLORINATED DRINKING WATER  

EPA Science Inventory

Chlorpyrifos (CP) is an organophosphate (OP) pesticide that was used as a model compound to investigate the transformation of OP pesticides at low pH and in the presence of bromide and natural organic matter (NOM) under drinking water treatment conditions. Raman spectroscopy was...

287

Investigations on the energy efficiency of organic and integrated farming with specific emphasis on pesticide use intensity  

Microsoft Academic Search

One organic farming treatment (OF) and two integrated farming treatments (IF) with (i) situation-related pesticide use (100% HF), and (ii) application rates reduced by 50% in relation to (i), (50% HF), were compared with regard to energy efficiency. Data were used from a long-term field experiment (1997–2006) conducted on a sandy soil with moderate soil fertility and continental climate in

S. Deike; B. Pallutt; O. Christen

2008-01-01

288

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...

289

Analysis of Organic Compounds in Returned Comet Nucleus Samples  

NASA Astrophysics Data System (ADS)

Comets are generally believed to be primitive bodies that preserve solar system matter in, or nearly in, its primordial state. This expectation has been at least partially borne out by the 1986 flyby missions to Comet Halley which provided data indicating that, with the exception of hydrogen, the light elements (C, N, O, and S) occur in approximately their solar abundances. Although mass spectrometers carried aboard the spacecraft provided much additional data from which to speculate about the molecular forms of these elements a detailed understanding of cometary organic chemistry will ultimately require the laboratory examination of returned samples. Some of the problems that will be encountered in such studies, for example, sensitivity to trace constituents, resolution of numerous isomeric forms, and avoidance of terrestrial contaminants, have already been faced in analyses of the organic compounds from carbonaceous chondrites. Furthermore, there is reason to believe that the progenitors of the carbonaceous chondrites were volatile rich planetesimals similar to those which, at greater radial distances, formed comets. Thus, the organic chemistry of carbonaceous chondrites may represent the outcome of a process of chemical evolution that parallels, although is perhaps further advanced than, that which occurred in comets. These meteorites may then represent not only a useful model for the development and refinement of analytical methods, but also a guide to the types of organic compounds that may be encountered in analyses of cometary matter. In this paper, I have (i) briefly reviewed the results of amino acid analyses of CM chondrites, (ii) discussed the origin of these compounds and the implications for comet organic chemistry, and (iii) described some recent developments in analytical instrumentation for amino acids and their implications for analyses of extraterrestrial materials. Although the emphasis is on amino acids, their general characteristics are common to the other classes of organic compounds in CM chondrites and inferences regarding their origins should be generally relevant.

Cronin, John R.

1997-12-01

290

Vertical distributions of persistent organic pollutants (POPs) caused from organochlorine pesticides in a sediment core taken from Ariake bay, Japan.  

PubMed

Persistent organic pollutants (POPs) of organochlorine pesticides such as dichlorodiphenyl trichloroethane (DDTs) and its metabolites, hexachlorobenzene (HCB), heptachlor, chlordane compounds (CHLs), aldrin, dieldrin, endrin, mirex and isomers of hexachlorocyclohexane (HCHs), were analyzed in sediment cores collected from Ariake Bay, Japan. Although Chikugo River has the largest flow in Ariake Bay, the total concentration of POPs in surface sediment was found in St.3, mouth of the Yabe River, where that level was two times higher than St.1, mouth of the Chikugo River. It could be assumed that the potential source of POPs contamination is relatively close to this study area. Relatively high residue levels of HCB, HCHs and DDTs in sediment core were found during the period from 1967 to 1970. In this layer, the HCB concentration investigated in sediment cores of Ariake Bay was maximum, 2.6 ng g(-1) dry weight and higher than that of Tokyo Bay and subsequently detected in deeper sediment cores. The ratio of (DDD+DDE)/SigmaDDTs was high in top sediments (0-2 cm). Although there was a concentration of DDTs in the top sediment, it was noticed that DDT emission did not cause direct input of DDT recently. The HCHs determined in upper sediment cores might be originated from long-range accumulation in environment after dispersing of technical-grade HCH. Moreover, the CHLs, dieldrin and heptachlor concentrations were detected and recently increased in sediment core. POPs in sediment cores of Ariake Bay based on the possibility of PCP contamination during the early 1960s were reflected. PMID:17109925

Kim, Yun-Seok; Eun, Heesoo; Katase, Takao; Fujiwara, Hideshi

2006-11-15

291

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...

292

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 29.4-64.2ngg(-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 (<0.4ngg(-1)), aldrin (<0.30ngg(-1)), dieldrin (<0.75ngg(-1)), endrin (<2.3ngg(-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

2013-08-22

293

Microextraction techniques for the determination of volatile and semivolatile organic compounds from plants: A review.  

PubMed

Vegetables and fruits are necessary for human health, and traditional Chinese medicine that uses plant materials can cure diseases. Thus, understanding the composition of plant matrix has gained increased attention in recent years. Since plant matrix is very complex, the extraction, separation and quantitation of these chemicals are challenging. In this review we focus on the microextraction techniques used in the determination of volatile and semivolatile organic compounds (such as esters, alcohols, aldehydes, hydrocarbons, ketones, terpenes, sesquiterpene, phenols, acids, plant secondary metabolites and pesticides) from plants (e.g., fruits, vegetables, medicinal plants, tree leaves, etc.). These microextraction techniques include: solid phase microextraction (SPME), stir-bar sorptive extraction (SBSE), single drop microextraction (SDME), hollow fiber liquid phase microextraction (HF-LPME), dispersive liquid liquid microextraction (DLLME), and gas purge microsyringe extraction (GP-MSE). We have taken into consideration papers published from 2008 to the end of January 2013, and provided critical and interpretative review on these techniques, and formulated future trends in microextraction for the determination of volatile and semivolatile compounds from plants. PMID:24091369

Yang, Cui; Wang, Juan; Li, Donghao

2013-08-06

294

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

Technology Transfer Automated Retrieval System (TEKTRAN)

Silage, fermented cattle feed, has recently been identified as a significant source of volatile organic compounds (VOCs) emitted 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 r...

295

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

296

Poly(phthalazine ether sulfone ketone) as novel stationary phase for stir bar sorptive extraction of organochlorine compounds and organophosphorus pesticides.  

PubMed

A novel poly(phthalazine ether sulfone ketone) (PPESK) film prepared by immersion precipitation technique was coated on stir bars for sorptive extraction. Scanning electron micrographs showed that the coating has a denser porous surface (about 1 microm in thickness) with a sponge-like sublayer, and the thickness of the coating was 250 microm. The PPESK coated stir bar has high thermostability (290 degrees C) and long lifetime (50 times). The extraction properties of this stir bar were evaluated for the extraction of both polar and semi-polar analytes, including organochlorine compounds and organophosphorus pesticides. The PPESK stir bar was proved to show higher affinity towards polar compounds than that of PDMS coated stir bar and higher sample load compared with corresponding PPESK fiber. It was applied to the determination of organochlorine compounds in seawater samples and organophosphorus pesticides in juices by gas chromatographic analysis. The effect of sample matrix was evaluated at optimized condition of extraction temperature, extraction time and salt concentration. Limits of detection were in the range of 0.05-2.53 ng L(-1) for organochlorine compounds in seawater samples using electron capture detector (ECD), with precisions of less than 11% RSD. Limits of detection for organophosphorus pesticides were in the range of 0.17-2.25 ng L(-1) and 2.47-10.3 ng L(-1) in grape and peach juice, respectively, using thermionic specified detector (TSD), with precisions of less than 12% RSD and 20% RSD, respectively. PMID:18037430

Guan, Wenna; Wang, Yanjuan; Xu, Feng; Guan, Yafeng

2007-11-01

297

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

298

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

PubMed

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. 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

1999-06-01

299

40 CFR 455.20 - Applicability; description of the organic pesticide chemicals manufacturing subcategory.  

Code of Federal Regulations, 2010 CFR

...Bacillus thuringiensis, insect growth hormones, plant extracts such as pyrethrins; sex...coverage in this subpart. (d) A plant that manufactures a pesticide active...of this part (NSPS and PSNS). A plant that manufactures a...

2010-07-01

300

40 CFR 455.20 - Applicability; description of the organic pesticide chemicals manufacturing subcategory.  

Code of Federal Regulations, 2010 CFR

...Bacillus thuringiensis, insect growth hormones, plant extracts such as pyrethrins; sex...coverage in this subpart. (d) A plant that manufactures a pesticide active...of this part (NSPS and PSNS). A plant that manufactures a...

2009-01-01

301

40 CFR 455.20 - Applicability; description of the organic pesticide chemicals manufacturing subcategory.  

Code of Federal Regulations, 2013 CFR

...Bacillus thuringiensis, insect growth hormones, plant extracts such as pyrethrins; sex...coverage in this subpart. (d) A plant that manufactures a pesticide...this part (NSPS and PSNS). A plant that manufactures a...

2013-07-01

302

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

303

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

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Standard for volatile organic compounds (VOC). 60.112b Section... Standards of Performance for Volatile Organic Liquid Storage Vessels (Including Petroleum... § 60.112b Standard for volatile organic compounds (VOC). (a) The...

2013-07-01

304

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

305

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

306

Transfer kinetics of polar organic compounds over polyethersulfone membranes in the passive samplers POCIS and Chemcatcher.  

PubMed

Passive samplers for polar organic compounds often use a polyethersulfone (PES) membrane to retain the particulate sorbent material (e.g., in a POCIS; polar organic chemical integrative sampler) or to reduce the sampling rate and thus extend the kinetic regime (e.g., in a Chemcatcher). The transport kinetics over the PES membrane are evaluated here in a short-term (6 days) and a long-term (32 days) experiment with POCIS and Chemcatchers. Passive samplers were placed in a channel with flowing river water that was spiked with 22 organic chemicals including pharmaceuticals, pesticides and biocides; with logK(ow) (logarithmic octanol-water partitioning coefficient) values between -2.6 and 3.8. Samplers were removed at intervals and membranes and sorbent material were extracted and analyzed with LC-MS/MS. Uptake kinetics of the compounds fell between two extremes: (1) charged chemicals and chemicals of low hydrophobicity did not accumulate in PES and rapidly transferred to the sorbent (e.g., diclofenac) and (2) more hydrophobic chemicals accumulated strongly in the PES and appeared in the sorbent after a lag-phase (e.g., diazinon and diuron). Sorption kinetics were modeled with a three-compartment first-order kinetic model to determine uptake and elimination rate constants and partitioning coefficients. Water PES partitioning coefficients fitted with the model correlated well with experimentally determined values and logK(ow). Sampling rates of Chemcatcher (0.02-0.10 L/d) and POCIS (0.02-0.30 L/d) showed similar patterns and correlated well. Thus the samplers are interchangeable in practical applications. Longer lag-phases may pose problems when calculating time-weighted average aqueous concentrations for short passive sampling windows and for a correct integrative sampling of fluctuating concentrations. PMID:22594693

Vermeirssen, Etiënne L M; Dietschweiler, Conrad; Escher, Beate I; van der Voet, Jürgen; Hollender, Juliane

2012-06-01

307

Metamaterial resonator arrays for organic and inorganic compound sensing  

NASA Astrophysics Data System (ADS)

In this paper, an electromagnetic metamaterial resonator operating in the terahertz frequency range is presented. By arranging the resonator in a planar array, it is possible to use the structure as a sensing device for organic and inorganic compounds. The sensor is designed to detect the presence of a biological compound by permittivity or absorption measurements. The presence of the biological matter modifies the effective permittivity and, thus, the resonant frequency significantly varies. In addition, biological compounds typically exhibit absorption characteristics that depend on the corresponding molecular structure. Therefore, it is necessary to illuminate the material selectively. We show that by employing the "selective" properties of the metamaterial resonator proposed, it is possible to enhance the sensing performances. The proposed design is suitable to sense the presence of healthy and malignant tissues, with possible applications in food and medical diagnostics. The operation of the sensing device has been demonstrated through proper full-wave simulations.

La Spada, Luigi; Bilotti, Filiberto; Vegni, Lucio

2011-09-01

308

Nonlinear Laser Fluorescence Spectroscopy of Natural Organic Compounds  

NASA Astrophysics Data System (ADS)

Principles of nonlinear laser fluorescence spectroscopy of complicated organic compounds and of the method capable of determining photophysical parameters are considered in this chapter. Special attention is paid to the peculiarities of the method connected with specific photophysical processes in natural organic compounds, especially in proteins, and to the major role of intramolecular energy transfer and presence of localized donor-acceptor pairs (LDAP) of fluorophores within single macromolecules. These facts stimulated the development of models based on the collective states formalism describing fluorescent response of LDAP to pulsed laser excitation. Unique features of the method are illustrated by the example of proteins (proteins with intrinsic fluorescence (HSA, BSA) and fluorescent protein mRFP1) that can be used as fluorescent tags of intracellular processes while their photophysical parameters can be used as the information channel.

Fadeev, Victor V.; Shirshin, Evgeny A.

309

Transformations of organic compounds under the action of mechanical stress  

NASA Astrophysics Data System (ADS)

Transformations of organic compounds (monomeric and polymeric) under the action of mechanical stress are considered. Two types of processes occur under these conditions. The first type involves disordering and amorphisation of crystal structure and conformational transformations as a result of rupture of intermolecular bonds. The second type includes mechanochemical reactions activated by deformation of valence bonds and angles under mechanical stress, namely, the rupture of bonds, oxidation and hydrolysis. Data on the organic mechanochemical synthesis of new compounds or molecular complexes are systematised and generalised. It is demonstrated that mechanical treatment ensures mass transfer and the contact of reacting species in these reactions. Proteins are especially sensitive to mechanical stress and undergo denaturation; enzymes are inactivated. The bibliography includes 115 references.

Dubinskaya, Aleksandra M.

1999-08-01

310

Concentration stability of four volatile organic compounds in soil subsamples  

SciTech Connect

This study assesses the short-term (14- to 20-day) concentration stability of benzene, toluene, trans-1,2-dichloroethylene and trichloroethylene in soil matrices, in the absence of volatilization losses. Previously, holding time studies failed to eliminate volatilization as a variable, making them difficult to interpret. Here, vapor-fortified soil subsamples, sealed in glass ampoules for 16 days, experienced appreciable reductions in benzene, presumably attributable only to biodegradation. Treated soil subsamples, on the other hand, prepared without vapor losses for either aqueous extraction headspace or purge-and-trap analyses, showed appreciable reductions in toluene and lost all the benzene over a 14-day holding period at 4 deg C. These findings suggest that chemical preservatives are necessary to maintain volatile organic compound concentrations in soil when more than a couple of days pass between collection and analysis. Biodegradation, Soil samples, Holding time, Volatile-organic compounds.

Hewitt, A.D.

1994-04-01

311

Volatile organic compound (VOC) species data manual. Second edition  

SciTech Connect

This document contains tables of potential emissions of organic compounds for selected source categories. The species profile table format has been organized to be particularly useful in preparation of emission inventory inputs to photochemical modeling. Accompanying each VOC profile table is a brief narrative that describes process, emissions, controls, and basis of source report and data quantification. The chemical classifications include paraffin, olefin, aromatic, carbonyl (aldehydes and ketones), methane, non-reactive other than methane, and miscellaneous. Data confidence levels for each profile table have been assigned. Reports, published data, and names and titles of personal contacts are referenced for each source category.

Not Available

1980-07-01

312

Orientation dependent molecular friction on organic layer compound crystals  

NASA Astrophysics Data System (ADS)

High resolution friction force maps of the benzylammonium terminated crystalline surface of a layer compound are presented. The lateral force map acquired with an atomic force microscope, reveals a significant contrast between different molecular orientations yielding molecular rows which differ from their neighboring ones. The single crystals are formed by stacks of copper oxalate sheets sandwiched between stereoregular organic cations, resulting in highly organized surface structures. Single molecular defects are observed at small loads. The experimental results are compared with numerical calculations which indicate a transition from an unperturbed state at small loads to a distorted state at higher loads.

Fessler, Gregor; Zimmermann, Iwan; Glatzel, Thilo; Gnecco, Enrico; Steiner, Pascal; Roth, Raphael; Keene, Tony D.; Liu, Shi-Xia; Decurtins, Silvio; Meyer, Ernst

2011-02-01

313

Emission of volatile organic compounds (VOCs) from PVC floor coverings.  

PubMed

In this study 29 PVC floor coverings were tested for emission of vinyl chloride (VC) and other volatile organic compounds (VOCs). A study on the effect of higher temperature on emission of VOCs from newly manufactured PVC flooring was also carried out. The study was conducted in climatic chamber, according to Polish Standard PN-89/Z-04021. GC method was used for analyzing of the compounds emitted. VC was not emitted from any of the floorings tested. Other VOCs were emitted in different concentrations. The influence of temperature on emission was conducted at temperatures of 23 degrees C and 35 degrees C from 2 hrs up to 180 days after introduction of materials in the chamber. The increase of temperature caused increase of total volatile organic compounds (TVOC) emission during 24 hrs of experiment. Then the emission was comparable for both temperatures. After 9 days emission of identified and unidentified compounds (TVOC) showed a rapid decay and stayed on very low level during a few months. The study conducted showed that PVC floorings after 10 days of installation in the room should not be source of indoor air contamination. PMID:10431652

Wiglusz, R; Igielska, B; Sitko, E; Nikel, G; Jarnuszkiewicz, I

1998-01-01

314

Destruction of organic compounds in water using supported photocatalysts  

SciTech Connect

Photocatalytic destruction of organic compounds in water is investigated using tanning lamps and fixed-bed photoreactors. Platinized titanium dioxide (Pt-TiO{sub 2}) supported on silica gel is used as a photocatalyst. Complete mineralization of influent concentrations of 4.98 mg/L tetrachloroethylene and 2.35 mg/L p-dichlorobenzene requires a reactor residence time less than 1.3 minutes. While for influent concentrations of 3.58 mg/L 2-chlorobiphenyl, 2.50 mg/L methyl ethyl ketone and 0.49 mg/L carbon tetrachloride, complete mineralization requires reactor residence times of 1.6, 10.5, and 16.8 minutes, respectively. A reactor model is developed using Langmuir-Hinshelwood kinetics and the model parameters are determined using a reference compound, trichloroethylene. Based on the results of experiments with trichloroethylene, the model predicts the mineralization of the aforementioned compounds from ultraviolet (UV) irradiance, influent concentration, hydroxyl radical rate constants, and the known physical properties of the compounds. The model is also able to predict organic destruction using solar insolation (which has a different spectral distribution from the tanning lamps) based on the UV absorption characteristics of titanium dioxide.

Zhang, Y.; Crittenden, J.C.; Hand, D.W.; Perram, D.L. [Michigan Technological Univ., Houghton, MI (United States). Dept. of Civil and Environmental Engineering

1996-05-01

315

Volatile organic compound emissions: an inventory for Western Europe  

SciTech Connect

The report gives details of an inventory compiled by CONCAWE and covering man-made non-methane volatile organic compound (VOC) emissions in Western Europe. The survey shows that the major man-made sources are road transport and solvents, each contributing around 40%. Total oil industry operations account for around 8%, with refining operations contribution about 2%. The major oil industry contribution comes from the distribution of gasoline, including vehicle refuelling (5%).

Edwards, A.H.; Campobasso, A.; Camps, R.; Cremer, G.; Long, M.D.

1986-01-01

316

Compositions of volatile organic compounds and methods of use thereof  

US Patent & Trademark Office Database

The present invention provides compositions and methods for treating, inhibiting or preventing the developing of a plant pathogenic disease. The compositions comprise volatile organic compounds effective to inhibit the growth of, or kill pathogenic microbes, including Ganoderma boninense. Invention compositions are especially useful in preventing and treating basal stem rot in the oil palm, and can be applied in the vicinity of the plant or used to sterilize the plant growth medium prior to or concurrent with plant growth therein.

2013-04-23

317

Determination of total volatile organic compound emissions from furniture polishes  

Microsoft Academic Search

In this study, an environmental test chamber with controlled temperature, relative humidity, and airflow rate was developed\\u000a to evaluate emissions of total volatile organic compounds (TVOCs) from three different kinds of furniture polish. The time\\u000a dependence of TVOC concentrations produced from the emissions of furniture polish products in the chamber was tested. TVOC\\u000a emissions from each furniture polish were compared.

Hai Guo; Frank Murray

2001-01-01

318

Influence of sorbate structure on nonequilibrium sorption of organic compounds  

Microsoft Academic Search

The authors investigate the relationship between sorbate structure and nonequilibrium sorption. The rate-limited sorption of compounds representing eight classes of organic chemicals, including chlorinated benzenes, unsubstituted and alkyl-substituted aromatics, chlorinated ethenes and ethanes, chlorinated phenols, nitrogen heterocycles, s-triazines, substituted amides, and substituted ureas, was examined by use of a single sorbent (sandy aquifer material) and the miscible displacement technique. The

Mark L. Brusseau; P. Suresh C. Rao

1991-01-01

319

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

320

Relationships between melting point and boiling point of organic compounds  

SciTech Connect

Relationships between melting point and boiling point are shown to be dependent upon the molecular symmetry number and a modified count of the total number of atoms in the molecule. Using the above relationships, the boiling and melting points of nearly 1,000 non-hydrogen-bonding organic compounds have been correlated. The correlations for boiling point and melting point have root mean square errors of 28 and 36 C, respectively.

Yalkowsky, S.H.; Krzyzaniak, J.F.; Myrdal, P.B. (Univ. of Arizona, Tucson, AZ (United States). College of Pharmacy)

1994-07-01

321

Gas-phase degradation of organic compounds in the troposphere  

Microsoft Academic Search

The present status of knowledge of the gas-phase reactions of selected classes of volatile non-methane organic compounds (NMOCs) (alkanes, alkenes, aromatic hydrocarbons, oxygen-containing NMOCs and nitrogen-containing NMOCs) and their degradation products in the troposphere is briefly discussed. In the troposphere, NMOCs can undergo photolysis, reaction with the hydroxyl (OH) radical during daylight hours, reaction with the nitrate (NO3) radical (primarily

Roger Atkinson

1998-01-01

322

Identification of nonmethane organic compound emissions from grassland vegetation  

Microsoft Academic Search

Emissions of nonmethane organic compounds (NMOCs) from grassland vegetation were collected in Summa® passivated stainless-steel canisters with a static enclosure technique and were analyzed by high-resolution gas chromatography with flame ionization and ion trap mass spectrometric detectors. Approximately 40NMOCs with 6–10 carbon atoms were observed in samples analyzed by high-resolution gas chromatography with the flame ionization detector. Nineteen NMOCs in

Yoshiko Fukui; Paul V. Doskey

2000-01-01

323

The synthesis of organic and inorganic compounds in evolved stars  

Microsoft Academic Search

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

Sun Kwok

2004-01-01

324

Oxidation of organic compounds in a microstructured catalytic reactor  

Microsoft Academic Search

A microstructured catalytic reactor for the oxidation of organic compounds has been fabricated from aluminum alloy AlMgSiCu1 (6082 series, Al51st). The catalyst section was assembled of 63 microstructured plates with catalytic coating. In each plate of 416?m thickness, 45 semi-cylindrical microchannels of 208?m in radius with a distance in between of 150?m were electrodischarge machined. A porous alumina layer of

I. Z. Ismagilov; E. M. Michurin; O. B. Sukhova; L. T. Tsykoza; E. V. Matus; M. A. Kerzhentsev; Z. R. Ismagilov; A. N. Zagoruiko; E. V. Rebrov; J. C. Schouten

2008-01-01

325

DFT derived solvation models for organic compounds in alkane solvents  

NASA Astrophysics Data System (ADS)

From a density functional theory (DFT) analysis of solvation and the different components which comprise the free energy of solvation we propose quantitative structure property relationship (QSPR) models to predict free energy of solvation, ?GS0, of organic compounds in seven alkane solvents (n-pentane, n-hexane, n-heptane, n-octane, n-nonane, n-decane, and n-hexadecane). The data contains 151 structurally different compounds containing diverse organic functions: unbranched and branched alkanes, cycloalkanes, aromatics, alcohols, aldehydes, ketones, esters, ethers, amines, nitriles, pyridines, fluorinated hydrocarbons, thiols, sulfides, carboxylic acids and nitro hydrocarbons; covering a ?GS0 range from about -50 to 0 kJ/mol. The models for the seven n-alkane solvents contain the same two molecular descriptors, one DFT descriptor (softness) and one geometric (molecular surface area). This fact suggests that the physical mechanisms behind the solvation of organic compounds in n-alkane solvents are of the same nature, as expected from the similar physical and chemical properties of alkanes. The models proposed have the merit of predicting free energy of solvation in alkane solvents with fewer descriptors than other QSPR models reported in the literature having similar statistics, allowing in this way a well-defined physical interpretation. The two descriptors have definite physical meaning corresponding to the different components which comprise free energy of solvation. Thus, the models proposed reach the desired compromise among simpleness, physical interpretation and computation time.

Delgado, Eduardo J.; Alderete, Joel B.; Jaña, Gonzalo A.

2006-06-01

326

Antiandrogenic Activity and Metabolism of the Organophosphorus Pesticide Fenthion and Related Compounds  

Microsoft Academic Search

tude to that of flutamide. Fenthion also tested positive in the Hershberger assay using castrated male rats. Marked estrogenic and antiestrogenic activities of fenthion and related compounds were not observed in MCF-7 cells. When fenthion was incubated with rat liver microsomes in the presence of NADPH, the antiandrogenic activity markedly decreased, and fenthion sulfoxide was detected as a major metabolite.

Shigeyuki Kitamura; Tomoharu Suzuki; Shigeru Ohta; Nariaki Fujimoto

2003-01-01

327

Occurrence of selected trace elements and organic compounds and their relation to land use in the Willamette River basin, Oregon, 1992-94  

USGS Publications Warehouse

Between 1992 and 1994, the U.S. Geological Survey conducted a study of trace elements and organic compounds in the Willamette River Basin, Oregon, as part of the Willamette River Basin Water Quality Study. Low-level analyses were performed for trace elements, volatile organic compounds, organochlorine compounds, and pesticides. Overall, 94 water samples were collected from 40 sites, during predominantly high-flow conditions, representing urban, agricultural, mixed, and forested land uses. Although most observed concentrations were relatively low, some exceedances of water-quality criteria for acute and chronic toxicity and for the protection of human health were observed. Concentrations of chromium, copper, lead, and zinc in unfiltered water were well correlated with concentrations of suspended sediment. The highest trace-element concen-trations generally were found at urban sites that receive a large portion of their runoff from industrial areas, particularly at high suspended-sediment concentrations. In contrast, concentrations of trace elements in some urban streams draining primarily residential areas appeared to approach a maximum as sediment concentrations increased. Whether this difference was due to a difference in the nature of the suspended sediments or to different concentrations in the aqueous phases from the two site types was not addressed. Eight organochlorine compounds were detected at 14 sites. Lindane, dieldrin, and DDT or its metabolites were each detected in about 30 percent of the samples, predominantly in samples collected from agricultural and urban areas. Polychlorinated biphenyl (PCB) compounds were detected in samples from two urban sites. For samples in which DDT and its metabolites were examined for partitioning, the largest proportion of the mass of DDT and its metabolites was associated with suspended sediment. In contrast, dieldrin and lindane were almost completely (greater than 99 percent) associated with the dissolved phase. Sixty-one of the 94 pesticides analyzed in filtered water were documented to have been used in the basin in 1987; 43 of these were detected at least once during 1992-94. An additional five were detected that were not documented in the 1987 estimates. Although a comparison between the frequency of detected pesticides and 1987 estimates of pesticide usage in the basin showed generally little correlation, some patterns of detections did appear to reflect land use in the basin. Of the 25 most frequently detected pesticides, 3 were found primarily at urban sites, 6 were found primarily at agricultural sites, and 7 were found at all types of sites except forested. The four most commonly detected pesticides in the basin, observed at all except for ested site types, were atrazine, metolachlor, simazine, and diuron. A greater variety of compounds was detected at sites in the northern portion of the basin than in the southern portion of the basin probably because the northern portion has more diverse agricultural practices and a larger urban component. Possible reasons for the lack of agree ment between pesticide detections and pesticide usage estimates include (1) uncertainty in the usage estimates due to spatial and temporal variability or due to changes in agricultural practices since the 1987 estimates were compiled, (2) chemical or biological transformations in the compounds after application, (3) variable hydrologic conditions among sites at the time of sampling, or (4) the ability of laboratory analytical procedures to detect low concentrations of some analytes. Results from repeated samplings at two sites during sequential storms in the fall of 1994 indicated that concentrations and loads of several constituents, including suspended sediment, suspended organic carbon, DDT, metolachlor, and atrazine were highest during peak flows of the first or second significant storms of the fall. Samplings during subsequent storms indicated that instantaneous concentrations and loads wer

Anderson, C. W.; Rinella, F. A.; Rounds, S. A.

1996-01-01

328

Contribution of organosulfur compounds to organic aerosol mass.  

PubMed

Organosulfates have been proposed as products of secondary organic aerosol formation. While organosulfates have been identified in ambient aerosol samples, a question remains as to the magnitude of their contribution to particulate organic mass. At the same time, discrepancies have been observed between total particulate sulfur measured by X-ray fluorescence (XRF) spectroscopy and sulfur present as inorganic sulfate measured by ion chromatography (IC) in fine particulate matter. These differences could be attributed to measurement bias and/or the contribution of other sulfur compounds, including organosulfates. Using the National Park Service IMPROVE PM(2.5) database, we examined the disparity between the sulfur and sulfate measurements at 12 sites across the United States to provide upper-bound estimates for the annual average contributions of organosulfates to organic mass. The data set consists of over 150000 measurements. The 12 sites include Brigantine, NJ, Cape Cod, MA, Washington, DC, Chassahowitzka, FL, Great Smoky Mountains National Park, NC, Okefenokee, GA, Bondville, IL, Mingo, MO, Phoenix, AZ, San Gabriel, CA, Crater Lake National Park, OR, and Spokane, WA. These sites are representative of the different regions of the country: Northeast, Southeast, Midwest, Southwest and Northwest. We estimate that organosulfur compounds could comprise as much as 5-10% of the organic mass at these sites. The contribution varies by season and location and appears to be higher during warm months when photochemical oxidation chemistry is most active. PMID:22731120

Tolocka, Michael P; Turpin, Barbara

2012-07-16

329

Interaction of Saharan dust particles with semivolatile organic compounds  

NASA Astrophysics Data System (ADS)

Mineral dust particles can be transported over long distances. During transport, mineral dust particles can interact with semi-volatile organic compounds present in the atmosphere, either as local pollution or as photochemical oxidation products of volatile species. Here we report on the interaction of organic species with mineral dust particles from the Sahara over an urban region. The dust samples were collected in Israel during spring 2001, covering several dust storm events. In an integrated, multi-technique study, using Scanning Electron Microscope equipped with energy dispersion system (SEM-EDS) and bulk aerosol analysis (gas chromatography/ mass spectrometry and ion chromatography methods), the organic and inorganic content of mineral dust particles collected during dust storms were studied. Particles were collected on 8-stages impactors for size segregated analysis, by high volume samplers for ion chromatography and GC analysis, on 47 mm PTFE filters for ion chromatography, and on silicon substrates for SEM-EDS analysis. Many mixed inorganic and organic particles were identified by individual particle SEM-EDS analysis of the collected particles. We will present the findings from the SEM analysis exemplifying the existence of the mixed particles. Using direct sample introduction followed by thermal desorption GC/MS and ion chromatography analysis, tracers for urban air pollution, of photochemical degradation products of biogenic volatile organic compounds as well as tracers of biomass burning were probed and quantified. The effect of the dust storms on the size distribution of semi-volatile organics will be discussed. Differences in the redistribution behavior between local pollution, photochemical degradation products and tracers of biomass burning will be highlighted.

Rudich, Y.; Falkovich, A. H.

2001-12-01

330

Decomposition of Organic Compounds at the Martian Surface  

NASA Astrophysics Data System (ADS)

The 1976 Viking Landers were unable to detect organic compounds indigenous to Mars or that which has been delivered to the surface through meteoritic accumulations. A number of mechanisms for destroying organic material have been proposed to explain the in-situ results. These include destruction by ultraviolet radiation as well as through reactions with active oxygen species, products of atmospheric photochemistry, and reactive surfaces produced by mineral fracturing. The results of chemical analyses preformed by the Alpha Particle X- ray Spectrometers (APXS) onboard the Mars Exploration Rovers (MER) suggest that yet another mechanism could have been active. The APXS data show a constant sulfur to chlorine ratio of approximately 3.7:1 for most samples of unconsolidated regolith. Due to the absence of an obvious cation, this observed ratio is not likely to be a product of mixing with distinct sulfate and chloride phases, but rather in the form of a rind on mineral grain surfaces. The initial source of the S and Cl is believed to be volcanic outgassing in the form of HCl, SO2, and H2SO4. Reactions with martian surface materials produce localized sulfates and chlorides. Interactions with acidic volatiles, however, are also extremely effective in decomposing organic compounds. All of the samples analyzed by the Viking Landers exhibited SO3 levels of approximately 6 weight percent or greater and S:Cl ratios consistent with the MER results, suggesting that extensive exposure to products of volcanic emissions could be the reason that martian organics were not detected. Future attempts to evaluate the carbon inventory of the martian surface environment will include instrumentation more sensitive than delivered by Viking, but the greatest chance of discovering carbon compounds on Mars may involve samples which have not been exposed to volcanic gases.

Yen, A. S.; Clark, B. C.; Hurowitz, J. A.; Athena Science Team

2006-12-01

331

Multiple microbial activities for volatile organic compounds reduction by biofiltration.  

PubMed

In the northeast of Italy, high volatile organic carbon (VOC) emissions originate from small-medium companies producing furniture. In these conditions it is difficult to propose a single, efficient, and economic system to reduce pollution. Among the various choices, the biofiltration method could be a good solution, because microbial populations possess multiple VOC degradation potentials used to oxidize these compounds to CO2. Starting from the air emissions of a typical industrial wood-painting plant, a series of experiments studied in vitro microbial degradation of each individual VOC. Isolated strains were then added to a laboratory-scale biofiltration apparatus filled with an organic matrix, and the different VOC behavior demonstrated the potential of single and/or synergic microbial removal actions. When a single substrate was fed, the removal efficiency of a Pseudomonas aeruginosa inoculated reactor was 1.1, 1.17, and 0.33 g m(-3) hr(-1), respectively, for xylene, toluene, and ethoxy propyl acetate. A VOC mixture composed of butyl acetate, ethyl acetate, diacetin alcohol, ethoxy propanol acetate, methyl ethyl ketone, methyl isobutyl ketone, toluene, and xylene was then fed into a 2-m(3) reactor treating 100 m3 hr(-1) of contaminated air. The reactor was filled with the same mixture of organic matrix, enriched with all of the isolated strains together. During reactor study, different VOC loading rates were used, and the behavior was evaluated continuously. After a short acclimation period, the removal efficiency was > 65% at VOC load of 150-200 g m(-3) hr(-1). Quantification of removal efficiencies and VOC speciation confirmed the relationship among removal efficiencies, compound biodegradability, and the dynamic transport of each mixture component within the organic matrix. Samples of the fixed bed were withdrawn at different intervals and the heterogeneous microbial community evaluated for both total and differential compound counts. PMID:16878585

Civilini, Marcello

2006-07-01

332

Determination of organic nitro compounds using HPLC-UV-PAED  

NASA Astrophysics Data System (ADS)

High-performance liquid chromatography with ultra violet and photo-assisted electrochemical detection (HPLC-UV-PAED) has been applied to the sensitive and selective determination of organic nitro compounds. The system was first developed for the determination of nitro explosives, and PAED has shown superior sensitivity over UV detection for these compounds (i.e., <1 part-per-trillion for HMX). The system also shows enhanced selectivity over the traditional UV method in that two detectors can be used for improved analyte identification. Also, having two detectors permits chemometric resolution of overlapping peaks, and this is not addressed in the UV method. Because this method is applicable to a wide range of nitro explosives, it was predicted that PAED would show the same sensitivity and selectivity toward other types of nitro compounds. Since its development, the system's use has been expanded to include the determination of nitro-containing pharmaceuticals and glycosylated nitro compounds in biological matrices. Model compounds were chosen, specifically nitroglycerin and related compounds and nitrophenyl-glucoside, to represent these classes. PAED showed superior detection limits over low wavelength UV detection for nitroglycerin (PAED = 0.3ppb, UV at 220nm = 48ppb), demonstrating PAED"s applicability to determining nitro-pharmaceuticals. Conversely, UV detection at 220nm proved to be more sensitive than PAED for nitrophenyl-glucoside (UV at 220 = 0.6ppb, PAED = 3.6ppb). However, when nitrophenyl-glucoside was spiked into urine, PAED determination resulted in 99+0.3% recovery, while UV at 220nm resulted in 116+0.2% recovery, suggesting that UV determination may suffer from matrix interference.

Marple, Ronita L.; LaCourse, William R.

2004-10-01

333

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...

334

Potential risks from exposure to organic compounds in indoor air  

SciTech Connect

This report is a preliminary assessment of the potential risks of cancer, reproductive effects, and miscellaneous toxic effects from exposures to individual organic compounds which have been detected in indoor air. Published data in indoor concentrations of organic compound were compiled. The principal basis for estimates of cancer were data from animal studies. Potency factors used in the risk calculations were estimated by EPA and by other authors. EPA potency factors were estimated by ''unit risk,'' the lifetime risk to humans from daily inhalation of a unit concentrations (e.g., 1 ..mu..g/m/sup 3/). A TD50 is defined as the daily dose rate that would induce tumor in half the test animals that would have remained tumor-free at zero dose. TD50s were converted to ''human equivalent inhalation'' TD50s to estimate cancer risks for median and maximum concentrations. Maximum likelihood (MLE) risks and 95% upper confidence limit risks were also calculated. For reproductive effects, the ''lowest effective dose'' (LED) in animals was converted to a ''human equivalent inhalation'' dose and compared to the maximum and the mean or median indoor concentrations reported for that compound. Based on the limited data available, it is concluded that risks of adverse health effects do not appear to be large in the great majority of homes. In some fraction of homes, however, a significant health risk may exist. 60 refs., 5 figs., 13 tabs.

McCann, J.; Horn, L.; Girman, J.; Nero, A.V.

1988-05-01

335

Pesticides in Uruguay.  

PubMed

This is a review, from an independent and scientific point of view, of the different aspects involved in the issue of pesticides in Uruguay. In its preparation, the University, responsible official institutions, nongovenment environmental organizations, and independent experts have been consulted. As to the legal framework, the responsibilities of the institutions are described and evaluated. The earlier and current regulations for the registration and sale of pesticides are presented, as well as the available information on the active ingredients most used in Uruguay. Official control is evaluated in reference to pesticide residues in food, drinking water, and the environment and to final waste disposal. Maximum allowed residue limits and the responsibilities of the corresponding governmental institutions are presented. Emphasis is placed on the fact that there are no publicly available data. Several research programs are presented, mainly from academia, and usually are not completed due to lack of financial support. In the conclusions the most problematic aspects are pointed out, emphasizing the need to improve national regulations for the country to establish an effective system of control. The importance of financial support to achieve this control and to conduct interdisciplinary studies to determine the real situation is discussed. All compounds are listed in Table 19. PMID:14738198

Mañay, N; Rampoldi, O; Alvarez, C; Piastra, C; Heller, T; Viapiana, P; Korbut, S

2004-01-01

336

Volatile organic compound losses from sewage sludge-amended soils  

SciTech Connect

Volatile organic compounds (VOCs) applied to soil in sludge have been assumed to disappear quickly and completely. The VOC behavior in sludge-amended soils has been studied previously only in laboratory systems where the sludged soil has been spiked with compounds of interest. Behavior in these systems may not necessarily represent compound behavior in field soils to which contaminated sludge is added. A series of laboratory microcosm experiments were designed therefore to investigate the behavior of toluene, ethyl benzene, o-, m-, and p-xylene applied to soil in contaminated sludge, and factors influencing loss processes. The VOC loss from sludge-amended soil was well described by a simple one step pseudo-first-order model but in certain soils was better described by a two step first-order model. Volatilization was the predominant loss process. Rates of loss depended on sludge application rate, method of sludge application, soil properties, and on compound characteristics. Experiments indicated that spiking sludge-amended soils gave a reasonable indication of VOC loss rates from systems amended with contaminated sludge at least over a period of 23 d. The majority of VOCs applied to soils in sludge volatilizes quickly to the atmosphere over a few to 10s of days with a small fraction lost more slowly. Potential for VOC crop uptake, livestock ingestion, and contamination of ground water is low under routine, managed applications of sewage sludge to agricultural land.

Wilson, S.C.; Jones, K.C.

1999-08-01

337

Microbial degradation of water-insoluble organic compounds  

SciTech Connect

The effect of solubilization on biodegradation of water-insoluble organic compounds was investigated. The effect of particle size on solubilization and degradation of 4-chlorobiphenyl (4-CB) and naphthalene by a microbial mixture was determined. The concentration of soluble compound was determined using gas-liquid chromatography. The rates of solubilization were inversely related to particle size for both compounds. The rates of mineralization of /sup 14/C-labeled palmitic acid, octadecane, di(2-ethylhexyl)phthalate (DEHP), and Sevin (1-naphthyl N-methylcarbamate) by microbial mixtures were determined by trapping the /sup 14/CO/sub 2/ formed, and those rates were compared to solubilization rates determined by periodically filtering sterile MS amended with one of the compounds. Mineralization and colonization of the surface of 10 ..mu..g palmitic acid per 10 ml MS by Pseudomonas pseudoflava was determined by trapping /sup 14/CO/sub 2/ and epifluorescence microscopy. Mineralization began before colonization and was initially exponential, but the rate then declined. The rate of mineralization at the end of the exponential phase approximated the rate of solubilization. The surface was completely covered about the time mineralization stopped. Unbound cells grew exponentially before colonization was detected; however, colonization of the surface was complete after the number of free cells stopped increasing. The data suggest that soluble palmitic acid is utilized before the insoluble phase but colonization is important in the mineralization of palmitic acid when solubilization becomes rate limiting.

Thomas, J.M.

1985-01-01

338

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

2012-07-14

339

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.

340

Removal of volatile organic compounds from paper coatings  

NASA Astrophysics Data System (ADS)

From the chemical point of view paper coatings are mainly polymer dispersions. Polymer dispersions are constituted in multitude fields, for example as dispersion coatings or adhesives. As far as no additional treatment is done, polymer materials as well as polymer agents contain non polymer, volatile organic components that may arise from: (1) incomplete polymerization of the applied monomers, (2) primary materials containing non polymerizable components, (3) undesirable side reactions during the synthesis. Requirements for the removal of volatile substances from polymer dispersion are given by several reasons: (1) low molecular substances deteriorate the product characteristics (viscosity, thermal stability and others), (2) in order to comply with legislative standards, volatile organic compounds have to be removed from dispersions, especially when applied to large surfaces (e.g. in surface refining in paper and leather industries as well as on coating). The removal of volatile organic compounds (deodorization) can be realized in continuous or discontinuous processes. In contrast to highly developed process technology, the process itself is not well understood, especially mass transport phenomena between the gas phase and the aqueous polymer dispersion are insufficiently and controversially discussed in the literature. Two processes, their advantages and disadvantages and the description by mathematical- mechanistic models are presented in this paper.

Meier, Dirk; Warnecke, Hans-Joachim; Pruess, Jan

1997-08-01

341

QSPR Modeling of Bioconcentration Factors of Nonionic Organic Compounds  

PubMed Central

The terms bioaccumulation and bioconcentration refer to the uptake and build-up of chemicals that can occur in living organisms. Experimental measurement of bioconcentration is time-consuming and expensive, and is not feasible for a large number of chemicals of potential regulatory concern. A highly effective tool depending on a quantitative structure-property relationship (QSPR) can be utilized to describe the tendency of chemical concentration organisms represented by, the important ecotoxicological parameter, the logarithm of Bio Concentration Factor (log BCF) with molecular descriptors for a large set of non-ionic organic compounds. QSPR models were developed using multiple linear regression, partial least squares and neural networks analyses. Linear and non-linear QSPR models to predict log BCF of the compounds developed for the relevant descriptors. The results obtained offer good regression models having good prediction ability. The descriptors used in these models depend on the volume, connectivity, molar refractivity, surface tension and the presence of atoms accepting H-bonds.

Deeb, Omar; Khadikar, Padmakar V.; Goodarzi, Mohammad

2010-01-01

342

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

343

Identification of volatile organic compounds polluting the atmosphere  

SciTech Connect

For an exact evaluation of the state of man`s environment and to adopt preventive measures to reduce the effect of human influences on it, it is necessary to know the of pollutants entering the atmosphere from various industrial sources. Chromatography methods of analysis are used in most of the analytical methods proposed for the solution of this problem. They enable the identification of the individual substances or a number of compounds within a given class. The chromato-mass spectrometric (CMS) method using high performance capillary separation overcomes this limitation and makes it possible to identify a considerably larger number of organic pollutants of quite different types. At present a standard method is used in the USA for the determination of critical pollutants in the atmosphere of urban areas, which was developed by the Environmental Protection Agency. There are similar methods in operation in other countries.Investigations in this field are limited in character in the Soviet Union. The present work outlines the results of investigations carried out with respect to sampling and structural identification of volatile organic compounds in the atmosphere of urban areas. The methods are based on the principle of sorption of the organic pounds on a solid carrier with subsequent thermal desorption and transfer of the solid components to the chromatograph of a CMS system. Examples of the use of the adsorption concentration on Tenax type sorbents have been described in the literature. 6 refs., 3 figs., 3 tabs.

Zamureenko, V.A.; Matveev, A.K.; Shik, N.V. [A.N. Severtsov Inst. of Evolutionary Morphology and Animal Ecology, Moscow (Russian Federation)] [and others

1992-03-10

344

Passive sampling of selected pesticides in aquatic environment using polar organic chemical integrative samplers  

Microsoft Academic Search

Purpose  Polar chemical integrative samplers (POCIS) were examined for their sampling efficiency of 12 pesticides and one metabolite\\u000a commonly detected in surface waters. Laboratory-based calibration experiments of POCISs were conducted. The determined passive\\u000a sampling rates were applied for the monitoring of pesticides levels in Lake Amvrakia, Western Greece. Spot sampling was also\\u000a performed for comparison purposes.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  Calibration experiments were performed on

?nna-?krivi Thomatou; Ierotheos Zacharias; Dimitra Hela; Ioannis Konstantinou

345

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

346

Seeking organic compounds on Mars : in situ analysis of organic compounds by Gas Chromatography-Mass Spectrometry on MOMA experiment  

NASA Astrophysics Data System (ADS)

The search for signs of past or present life is one of the primary goals of future Mars exploratory missions. The Mars Organic Molecule Analyzer (MOMA) experiment of the ExoMars mission (set to launch 2016-2018) is a joint venture by the European Space Agency and NASA to develop a sensitive detector for organics on Mars. MOMA will be one of the main analytical instruments aboard the ExoMars Rover aimed at characterizing possible “signs-of-life molecules” in the Martian environment such as amino acids, carboxylic acids, nucleobases or polycyclic aromatic hydrocarbons (PAHs). With the aim to separate and detect organic compounds from Martian soil, the French MOMA team has built a gas chromatograph able to work in standalone mode by using a TCD detector. The gas chromatograph can also be coupled with an ion trap mass spectrometer developed by the US MOMA team. Moreover, a GC-MS compatible sample processing system (SPS) allowing the extraction and the chemical transformation of the organic compounds from the soil, that fits within space flight conditions, has also been developed. The sample processing is performed in an oven, dedicated to the MOMA experiment containing the solid sample (50-100mg). The internal temperature of oven can be ranged from 20 to 1000 °C which allows for pyrolysis, thermochemolysis or derivatization. The organic extraction step is achieved by using thermodesorption in the range of 100 to 300°C for 0.5 to 5 min. Then, the chemical derivatization and/or thermochemolysis of the extracted compounds is performed directly on the soil with a mixture of MTBSTFA-DMF, TMAH or DMF-DMA solution when enantiomeric separation is required. By decreasing the polarity of the target molecules, this step allows for their volatilization at a temperature below 250°C without any chemical degradation. Once derivatized, the volatile target molecules are trapped in a cold chemical trap and promptly desorbed into the gas chromatograph coupled to the mass spectrometer. Preliminary tests, performed on several analogue soils such as Atacama soil, with the MOMA SPS-GC/MS experiment demonstrated the capability to detect organic compounds such as amino and carboxylic acids with sensitivities below the ppm level.

Buch, A.; Freissinet, C.; Sternberg, R.; Pinnick, V.; Szopa, C.; Coll, P. J.; Rodier, C.; Garnier, C.; Steininger, H.; Moma Team

2010-12-01

347

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

348

Analysis of Selected Organic Priority Pollutants in Environmental Samples.  

National Technical Information Service (NTIS)

The analysis of drinking water for pesticides, herbicides, and volatile organic compounds will probably be the environmental analytical chemist's introduction to the Environmental Protection Agency (EPA) list of organic priority pollutants. The State of T...

R. J. McElhaney M. L. Mann

1980-01-01

349

Hazardous organic compounds in groundwater near Tehran automobile industry.  

PubMed

Potential of groundwater contamination by trichloroethylene (TCE) and other volatile organic compounds VOCs near car industry was conducted in this study. TCE, PCE, toluene, xylene, dichloromethane, cyclohexane, n-hexane and n-pentane were detected in all groundwaters. Mean TCE levels in groundwater ranged from 124.37 to 1,035.9 ?g L?¹ with maximum level of 1,345.7 ?g L?¹. Due to the data obtained from conventional wastewater treatment in car factory the TCE removal efficiency was only 24 percent which necessitates the TCE removal by advanced treatment processes before the use of well water. PMID:21069286

Dobaradaran, Sina; Mahvi, Amir Hossein; Nabizadeh, Ramin; Mesdaghinia, Alireza; Naddafi, Kazem; Yunesian, Masoud; Rastkari, Noushin; Nazmara, Shahrokh

2010-11-11

350

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

351

Volatile organic compounds in storm water from a parking lot  

USGS Publications Warehouse

A mass balance approach was used to determine the most important nonpoint source of volatile organic compounds (VOCs) in storm water from an asphalt parking lot without obvious point sources (e.g., gasoline stations). The parking lot surface and atmosphere are important nonpoint sources of VOCs, with each being important for different VOCs. The atmosphere is an important source of soluble, oxygenated VOCs (e.g., acetone), and the parking lot surface is an important source for the more hydrophobic VOCs (e.g., benzene). VOCs on the parking lot surface appear to be concentrated in oil and grease and organic material in urban particles (e.g., vehicle soot). Except in the case of spills, asphalt does not appear to be an important source of VOCs. The uptake isotherm of gaseous methyl tert-butyl ether on urban particles indicates a mechanism for dry deposition of VOCs from the atmosphere. This study demonstrated that a mass balance approach is a useful means of understanding non-point-source pollution, even for compounds such as VOCs, which are difficult to sample.A mass balance approach was used to determine the most important nonpoint source of volatile organic compounds (VOCs) in storm water from an asphalt parking lot without obvious point sources (e.g., gasoline stations). The parking lot surface and atmosphere are important nonpoint sources of VOCs, with each being important for different VOCs. The atmosphere is an important source of soluble, oxygenated VOCs (e.g., acetone), and the parking lot surface is an important source for the more hydrophobic VOCs (e.g., benzene). VOCs on the parking lot surface appear to be concentrated in oil and grease and organic material in urban particles (e.g., vehicle soot). Except in the case of spills, asphalt does not appear to be an important source of VOCs. The uptake isotherm of gaseous methyl tert-butyl ether on urban particles indicates a mechanism for dry deposition of VOCs from the atmosphere. This study demonstrated that a mass balance approach is a useful means of understanding non-point-source pollution, even for compounds such as VOCs, which are difficult to sample.

Lopes, T. J.; Fallon, J. D.; Rutherford, D. W.; Hiatt, M. H.

2000-01-01

352

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

Microsoft Academic Search

The functionalization of porous metal–organic frameworks (Cu3(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 N2 and volatile organic compounds (VOCs) adsorption measurements, including short-chain alcohols (C<4), cyclohexane, benzene, and toluene. The adsorption enthalpies

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

2011-01-01

353

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

354

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

355

75 FR 82363 - 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...and letterpress printing volatile organic compound (VOC) rule for approval into...with potential VOC ink oil emissions from the...

2010-12-30

356

Identifying organic nitrogen compounds in Rocky Mountain National Park aerosols  

NASA Astrophysics Data System (ADS)

Nitrogen deposition is an important issue in Rocky Mountain National Park (RMNP). While inorganic nitrogen contributions to the ecosystems in this area have been studied, the sources of organic nitrogen are still largely unknown. To better understand the potential sources of organic nitrogen, filter samples were collected and analyzed for organic nitrogen species. Samples were collected in RMNP using a Thermo Fisher Scientific TSP (total suspended particulate) high-volume sampler with a PM2.5 impactor plate from April - November of 2008. The samples presented the opportunity to compare two different methods for identification of individual organic nitrogen species. The first type of analysis was performed with a comprehensive two dimensional gas chromatography (GCxGC) system using a nitrogen chemiluminescence detector (NCD). The filter samples were spiked with propanil in dichloromethane to use as an internal standard and were then extracted in water followed by solid phase extraction. The GCxGC system was comprised of a volatility based separation (DB5 column) followed by a polarity based separation (RXI-17 column). A NCD was used to specifically detect nitrogen compounds and remove the complex background matrix. Individual standards were used to identify peaks by comparing retention times. This method has the added benefit of an equimolar response for nitrogen so only a single calibration is needed for all species. In the second analysis, a portion of the same filter samples were extracted in DI water and analyzed with liquid chromatography coupled with mass spectroscopy (LC/MS). The separation was performed using a C18 column and a water-methanol gradient elution. Electrospray ionization into a time of flight mass spectrometer was used for detection. High accuracy mass measurement allowed unambiguous assignments of elemental composition of resulting ions. Positive and negative polarities were used since amines tend to show up in positive mode and nitrates in negative. The differences in the number of species and what species are identified between these two methods are important for planning future analyses of organic nitrogen compounds. In addition, these data provide new insight into the potential source of organic nitrogen in RMNP. Using the GCxGC method, 39 organic nitrogen species were detected and 20 were identified. Identified species include several types of amines and phenols. The LC/MS method identified several types of cresols, amines, and nitrates.

Beem, K. B.; Desyaterik, Y.; Ozel, M. Z.; Hamilton, J. F.; Collett, J. L.

2010-12-01

357

Critical evaluation of interlaboratory comparisons for PAHs and pesticides in organic standard solutions in support of the implementation of the Water Framework Directive  

Microsoft Academic Search

Several proficiency tests were organized within the framework of a European project, called SWIFT-WFD, involved in implementing the Water Framework Directive (WFD). Among others, the parameters studied were polycyclic aromatic hydrocarbons (PAHs) and pesticides in organic standard solutions. The aim of this study was to evaluate the state of the art in Europe and possible sources of bias in calibration

Angels Sahuquillo; O BERCARU; F ULBERTH; R MORABITO; C BRUNORI; I IPOLYI; C PELLEGRINO

2007-01-01

358

Synthesis of Novel Organic-Inorganic Self-Organized Compounds Containing Quaternary Ammonium Ions and its Structural Characterization  

Microsoft Academic Search

Organic-inorganic layered perovskite compounds described by (RNH 3 ) 2 MX 4 [R: alkyl group, M: divalent metals, X: halogen] were reported to form self-organized quantum-well structures. In this study, we aimed to synthesize novel organic-inorganic self-organized compounds with quaternary ammonium ions instead of primary alkylammonium ions. New compounds, [(C 12 H 25 ) 2 (CH 3 ) 2 N]PbBr

Satoshi Kano; Kenjiro Teshima; Masahiro Rikukawa; Kohei Sanui

2002-01-01

359

Modeling Emissions of Volatile Organic Compounds from New Carpets  

SciTech Connect

A simple model is proposed to account for observed emissions of volatile organic compounds (VOCs) from new carpets. The model assumes that the VOCs originate predominantly in a uniform slab of polymer backing material. Parameters for the model (the initial concentration of a VOC in the polymer, a diffusion coefficient and an equilibrium polymer/air partition coefficient) are obtained from experimental data produced by a previous chamber study. The diffusion coefficients generally decrease as the molecular weight of the VOCs increase, while the polymer/air partition coefficients generally increase as the vapor pressure of the compounds decrease. In addition, for two of the study carpets that have a styrene-butadiene rubber (SBR) backing, the diffusion and partition coefficients are similar to independently reported values for SBR. The results suggest that predictions of VOCs emissions from new carpets may be possible based solely on a knowledge of the physical properties of the relevant compounds and the carpet backing material. However, a more rigorous validation of the model is desirable.

Little, J.C.; Hodgson, A.T.; Gadgil, A.J.

1993-02-01

360

Indoor chemistry. Ozone, volatile organic compounds, and carpets  

SciTech Connect

Volatile organic compounds (VOCs) have been measured in a freshly carpeted 20-m[sup 3] stainless-steel room in both the absence and presence of ozone (ozone concentrations ranging from 30 to 50 ppb, with one experiment conducted at 400 ppb). Four different types of carpeting were exposed, and in each set of experiments, the room was ventilated at 1 air exchange/h. The gas-phase concentrations of selected carpet emissions (e.g., 4-phenylcyclohexene, 4-vinylcyclohexene, and styrene) significantly decreased in the presence of ozone. Conversely, the concentrations of other compounds (e.g., formaldehyde, acetaldehyde, and aldehydes with between 5 and 10 carbons) significantly increased. Furthermore, the total concentration of VOCs increased markedly in the presence of ozone. The additional VOCs appear to have been generated by reactions between ozone and relatively nonvolatile compounds associated with the carpets. These studies suggest that VOCs measured within a building at elevated ozone levels (>30 ppb) may differ from those measured at lower ozone levels (<10 ppb). 12 refs., 2 figs., 6 tabs.

Weschler, C.J. (Bell Communications Research, Red Bank, NJ (United States)); Hodgson, A.T.; Wooley, J.D. (Lawrence Berkeley Lab., CA (United States))

1992-12-01

361

Degradation of volatile organic compounds with thermally activated persulfate oxidation.  

PubMed

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 1 g l(-1) and 5 g l(-1) and at temperatures of 20 degrees C, 30 degrees C, and 40 degrees C were obtained. The results indicate that persulfate oxidation mechanisms are effective in degrading many VOCs including chlorinated ethenes (CEs), BTEXs and trichloroethanes that are frequently detected in the subsurface at contaminated sites. Most of the targeted VOCs were rapidly degraded under the experimental conditions while some showed persistence to the persulfate oxidation. Compounds with "CC" bonds or with benzene rings bonded to reactive functional groups were readily degraded. Saturated hydrocarbons and halogenated alkanes were much more stable and difficult to degrade. For those highly persulfate-degradable VOCs, degradation was well fitted with a pseudo first-order decay model. Activation energies of reactions of CEs and BTEXs with persulfate were determined. The degradation rates increased with increasing reaction temperature and oxidant concentration. Nevertheless, to achieve complete degradation of persulfate-degradable compounds, the systems required sufficient amounts of persulfate to sustain the degradation reaction. PMID:16202809

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

2005-04-12

362

[Discharge ion mobility spectrometry of ketonic organic compounds].  

PubMed

Ion mobility spectrometry (IMS) is a sensitive technique for fast on-line monitoring trace volatile organic compounds based upon the mobilities of gas phase ions at ambient pressure in weak electric field. In the present work, protonated water reactant ions were successfully prepared, and eight ketones were studied on a homemade high-resolution IMS apparatus using a discharge ionization source. The reduced mobility values of all ions were derived from the observed ion mobility spectra. The experimentally determined reduced mobilities for acetone, 2-butone, 1-methyl-2-pyrrolidinone acetophenone, cyclohexanone and product ions were compared with the previously reported values in the Ni-IMS, indicating that they are in good agreement. The reduced mobilities of methyl isopropyl ketone, 4-methyl-2-pentanone and cyclopentanone ions were given for the first time. The ionization process for organic compounds in the authors' discharge ion mobility spectrometer is suggested to be similar to Ni-IMS system, i.e., the proton transfer reactions produce protonated ketone ions. In addition, a linear correlation was found between the reduced mobilities of the ketone ions and their molecular masses. Qualitative measurements show that the limit of detection is in the ng x L(-1) order of magnitude in the authors' discharge ion mobility spectrometer. PMID:17655083

Huang, Guo-dong; Han, Hai-yan; Jia, Xian-de; Jin, Shun-ping; Li, Jian-quan; Wang, Hong-mei; Tang, Xiao-shuan; Jiang, Hai-he; Chu, Yan-nan; Zhou, Shi-kang

2007-05-01

363

Reactive uptake of organic compounds by liquid sulfuric acid.  

NASA Astrophysics Data System (ADS)

The uptake of several organic compounds by laboratory surrogates for tropospheric sulfuric acid particles were investigated by mass spectrometry and infrared reflection-absorption spectroscopy. Among the compounds studied were acetone [(CH_3)_2CO], 2,4-hexanedione [CH_3CO(CH_2)_2COCH_3, MBO], and 2-methyl-3-buten-2-ol [CH_2CHC(CH_3)_2OH]. Experiments were carried out on ultrathin sulfuric acid films (ca. 10-100 monolayer equivalents thick) as functions of organic partial pressure, temperature, and acid composition. Acetone uptake is irreversible for acids that contain >70 weight percent (wt. %) H_2SO4, with kinetics that are second-order in concentration of dissolved acetone. Hexanedione and MBO are irreversibly taken for all acid compositions investigated (60-96 wt. %), with first-order uptake kinetics. In all cases, the irreversible uptake is a consequence of sulfuric acid catalyzed reactions that lead to the formation of new C-C bonds. Implications of these results for heterogeneous tropospheric chemistry will be discussed.

Roberts, J.; Michelsen, R.

2003-04-01

364

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.

Oates, Liza; Cohen, Marc

2011-01-01

365

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

Code of Federal Regulations, 2013 CFR

...2013-07-01 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...

2013-07-01

366

Efficiency of organic compounds removal by electron-beam irradiation in presence of high metal concentration  

Microsoft Academic Search

The high efficiency of electron-beam irradiation process in removing organic compounds from industrial effluents has been established. The actual chemical, textile, pharmaceutical and industrial effluents contain a high level of organic and inorganic compounds. In this study, the organic compounds removal was evaluated in the simulated industrial effluents, using electron-beam irradiation. The samples were prepared by adding Na, Cl, Ca,

Celina L Duarte; Márcia A Ribeiro; Ivone M Sato; Maria Helena de O Sampa

2004-01-01

367

PRESENT STATUS AND PROSPECTS OF USING ORGANIC COMPOUNDS AS MODERATOR-HEAT CONDUCTORS IN ATOMIC REACTORS  

Microsoft Academic Search

Discussion is given on the use of organic compounds as moderator-heat ; conductors in nuclear reactors. The advantages of organic compounds over water ; are listed. However, organic compounds are harder to purify, have higher fusing ; points, are lower than water in heat exchange, and are vulnerable to destruction. ; Thus far tri-xenene mixtures have proved best for moderator-hent

1961-01-01

368

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

369

Origin and fate of organic compounds in water: characterization by compound-specific stable isotope analysis.  

PubMed

Within the past 15 years, compound-specific stable isotope analysis has continued to increase in popularity in the area of contaminant hydrology of organic molecules. In particular, in cases where concentration data alone are insufficient to elucidate environmental processes unequivocally, the isotope signature can provide additional unique information. Specifically, it can help answer questions about contaminant source apportionment, quantification of biotic and abiotic processes, and identification of transformation reactions on a mechanistic level. We review advances in laboratory and field investigations and exemplary applications in contaminant hydrology via stable isotope analysis. We also highlight future directions in the field. PMID:22482787

Schmidt, Torsten C; Jochmann, Maik A

2012-04-09

370

Marine mammal blubber reference and control materials for use in the determination of halogenated organic compounds and fatty acids.  

PubMed

The National Institute of Standards and Technology (NIST) has a diverse collection of control materials derived from marine mammal blubber, fat, and serum. Standard Reference Material (SRM) 1945 Organics in Whale Blubber was recertified for polychlorinated biphenyl (PCB) congeners, organochlorine pesticides, and polybrominated diphenyl ether (PBDE) congeners. SRM 1945 has also been assigned mass fraction values for compounds not frequently determined in marine samples including toxaphene congeners, coplanar PCBs, and methoxylated PBDE congeners which are natural products. NIST also has assigned mass fraction values, as a result of interlaboratory comparison exercises, for PCB congeners, organochlorine pesticides, PBDE congeners, and fatty acids in six homogenate materials produced from marine mammal blubber or serum. The materials are available from NIST upon request; however, the supply is very limited for some of the materials. The materials include those obtained from pilot whale blubber (Homogenates III and IV), Blainville's beaked whale blubber (Homogenate VII), polar bear fat (Homogenate VI), and California sea lion serum (Marine Mammal Control Material-1 Serum) and blubber (Homogenate V). PMID:20238106

Kucklick, John R; Schantz, Michele M; Pugh, Rebecca S; Porter, Barbara J; Poster, Dianne L; Becker, Paul R; Rowles, Teri K; Leigh, Stefan; Wise, Stephen A

2010-03-19

371

Pesticide\\/Environmental Exposures and Parkinson's Disease in East Texas  

Microsoft Academic Search

Epidemiological evidence suggests that pesticides and other environmental exposures may have a role in the etiology of idiopathic Parkinson's disease (PD). However, there is little human data on risk associated with specific pesticide products, including organic pesticides such as rotenone with PD. Using a case-control design, this study examined self-reports of exposure to pesticide products, organic pesticides such as rotenone,

Amanpreet S. Dhillon; G. Lester Tarbutton; Jeffrey L. Levin; George M. Plotkin; Larry K. Lowry; J. Torey Nalbone; Sara Shepherd

2008-01-01

372

[Biological function of some elements and their compounds. II. Selenium, selenate, selenium organic compounds].  

PubMed

The review is devoted to the role of selenium and its compounds for living organisms. Selenium as an antioxidant protects the cells from generating free radicals. It constitutes an integral part of approximately 20 enzymes. Glutathione peroxidase, which participates in metabolism of H2O2 and plays a protective role against lipids oxidation is one of the most important enzymes containing of selenium. In organisms, selenium occurs most frequently in amino acids, where it replaces sulphur, such as selenocystein and selenometionine, as well as in bonds with proteins. Amino acid bonds are significant in functions of RNA, in biosynthesis and activity of thyroid hormones. Selenium deficiency leads to decrease in selenium-dependent glutathione peroxidase, which occurs in mitochondria and cytosole. It causes also heart muscles diseases, the skeletal and circulatory systems disorders, neoplasms, infections, and cold. PMID:19827742

Puzanowska-Tarasiewicz, Helena; Ku?micka, Ludmila; Tarasiewicz, Miros?aw

2009-09-01

373

On the flux of oxygenated volatile organic compounds from organic aerosol oxidation  

NASA Astrophysics Data System (ADS)

Previous laboratory and field studies suggest that oxidation of organic aerosols can be a source of oxygenated volatile organic compounds (OVOC). Using measurements of atmospheric oxidants and aerosol size distributions performed on the NASA DC-8 during the INTEX-NA campaign, we estimate the potential magnitude of the continental summertime OVOC flux from organic aerosol oxidation by OH to be as large as ~70 pptv C/day in the free troposphere. Contributions from O3, H2O2, photolysis, and other oxidants may increase this estimate. These processes may provide a large, diffuse source of OVOC that has not been included in current atmospheric models, and thus have a significant impact on our understanding of organic aerosol, OVOC, PAN, and HOx chemistry. The potential importance and highly uncertain nature of our estimate highlights the need for more field and laboratory studies on organic aerosol composition and aging.

Kwan, Alan J.; Crounse, John D.; Clarke, Antony D.; Shinozuka, Yohei; Anderson, Bruce E.; Crawford, James H.; Avery, Melody A.; McNaughton, Cameron S.; Brune, William H.; Singh, Hanwant B.; Wennberg, Paul O.

2006-08-01

374

Prediction of the sorption of organic compounds into soil organic matter from molecular structure.  

PubMed

A new model to estimate the soil-water partition coefficient of non-ionic organic compounds normalized to soil organic carbon, Koc, from the two-dimensional molecular structure is presented. Literature data of log Koc for 571 organic chemicals were fitted to 29 parameters with a squared correlation coefficient r2 of 0.852 and a standard error of 0.469 log units. The application domain includes the atom types C, H, N, O, P, S, F, Cl, and Br in various important compound classes. The multilinear model contains the variables molecular weight, bond connectivity, molecular E-state, an indicator for nonpolar and weakly polar compounds, and 24 fragment corrections representing polar groups. The prediction capability is evaluated through an initial two-step development using an 80%:20% split of the data into training and prediction, cross-validation, permutation, and application to three external data sets. The discussion includes separate analyses for subsets of H-bond donors and acceptors as well as for nonpolar and weakly polar compounds. Comparison with existing models including linear solvation energy relationships illustrates the superiority of the new model. PMID:17154008

Schüürmann, Gerrit; Ebert, Ralf-Uwe; Kühne, Ralph

2006-11-15

375

Effects of some pesticides on the vital organs of juvenile rainbow trout (Oncorhynchus mykiss).  

PubMed

Gill, trunk kidney, spleen, and liver of rainbow trout (Oncorhynchus mykiss) were examined after exposure to different sublethal concentrations of carbosulfan (25, 50 and 200 ?gL(-1)), propineb (3, 6 and 24 mgL(-1)), and benomyl (2, 5 and 20 mgL(-1)) for 14 days. Lesions were observed in gill, trunk kidney, spleen, and liver of rainbow trout exposed to either concentration of pesticides. The most important lesions were determined in the highest concentrations of pesticides. Lamellar fusion, lamellar hyperplasia, epithelial lifting, vacuolization of epithelial tissue, epithelial necrosis, hypertrophy and sloughing of epithelium were observed on fish exposed to carbosulfan, propineb and benomyl. Fish had cell necrosis, degeneration and oedemas in liver, trunk kidney and spleen. None of these lesions were seen in control fish. PMID:21051065

Capkin, Erol; Terzi, Ertugrul; Boran, Halis; Yandi, Ilhan; Altinok, Ilhan

2010-11-03

376

RESISTANCE TO PESTICIDES  

Technology Transfer Automated Retrieval System (TEKTRAN)

The occurrence of pesticide resistance stands as one of the most chronic and formidable problems for crop production and public health worldwide. The evolution of different resistance mechanisms by pestiferous organisms has diminished the lethal action of pesticides and led to greater difficulties ...

377

Organic volatile sulfur compounds in inland aquatic systems  

SciTech Connect

The speciation, concentration, and fluxes of organic volatile sulfur compounds (VSCs) in a wide variety of inland aquatic systems wee studied. Dissolved VSCs were sparged from water samples, trapped cryogenically, and quantified by gas chromatograph equipped with a flame photometric detector. Species detected and mean surface water concentrations were: carbonyl sulfide (COS), 0.091-7.6 nM; methanethiol (MSH), undetected-180 nM; dimethyl sulfide (DMS), 0.48-1290 nM; carbon disulfide (CS[sub 2]), undetected-69 nM; dimethyl disulfide (DMDS), undetected-68 nM. The range in surface water concentrations of over five orders of magnitude was influenced principally by lake depth and sulfate concentration ([SO[sub 4][sup 2[minus

Richards, S.R.

1991-01-01

378

Residential pollutants and ventilation strategies: Volatile organic compounds and radon  

SciTech Connect

This paper reviews literature that reports investigations of residential ventilation and indoor air quality. Two important residential pollutant classes, volatile organic compounds and radon, are examined. A companion paper examines moisture and combustion pollutants. Control strategies recommended from the review include appropriate building design to prevent or limit the sources of the pollutants within the space, proper operation and maintenance to prevent adverse conditions from developing during the building's life and appropriate use of ventilation. The characteristics of these pollutant sources suggest that ventilation systems in residences should have several properties. They should have the extra capacity available to reduce short bursts of pollution, be located close to the expected source of the contamination, and be inexpensive. Mitigation of radon is technically a major success using a form of task ventilation. Whole-house ventilation is, at best, a secondary form of control of excess radon in residences.

Grimsrud, D.T.; Hadlich, D.E.

1999-07-01

379

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

380

Biosynthesis, function and metabolic engineering of plant volatile organic compounds.  

PubMed

Plants synthesize an amazing diversity of volatile organic compounds (VOCs) that facilitate interactions with their environment, from attracting pollinators and seed dispersers to protecting themselves from pathogens, parasites and herbivores. Recent progress in -omics technologies resulted in the isolation of genes encoding enzymes responsible for the biosynthesis of many volatiles and contributed to our understanding of regulatory mechanisms involved in VOC formation. In this review, we largely focus on the biosynthesis and regulation of plant volatiles, the involvement of floral volatiles in plant reproduction as well as their contribution to plant biodiversity and applications in agriculture via crop-pollinator interactions. In addition, metabolic engineering approaches for both the improvement of plant defense and pollinator attraction are discussed in light of methodological constraints and ecological complications that limit the transition of crops with modified volatile profiles from research laboratories to real-world implementation. PMID:23383981

Dudareva, Natalia; Klempien, Antje; Muhlemann, Joëlle K; Kaplan, Ian

2013-02-06

381

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

382

A novel nanostructure for ultrasensitive volatile organic compound sensing  

NASA Astrophysics Data System (ADS)

We have developed an arrayed nanocoaxial structure for the ultrasensitive sensing detection and identification of volatile organic compounds (VOC) by dielectric impedance spectroscopy. VOC molecules are absorbed into porous dielectric material in the annulus between nanoscale coax electrodes. A theoretical expression for the basic adsorption mechanism agrees with the experimental results. Detection sensitivities at parts-per-billion levels were demonstrated for a variety of VOCs. A limit-of-detection of ethanol reached ˜100 parts-per-trillion, following a Freundlich power-law isotherm across four decades of ethanol concentration. A linear dependence on VOC dielectric constant was observed. Dielectric impedance nanospectroscopy was also performed by scanning frequency from 10 mHz to 1 MHz, with distinctive spectra of different VOCs discovered. These were utilized to conduct colorimetric identification of VOCs. The results suggest our novel nanocoaxial sensor can be used as a sensitive, broadband, and multimodal sensing platform for chemical detection.

Zhao, Huaizhou; Rizal, Binod; Ren, Zhifeng; Naughton, Michael J.; Chiles, Thomas C.; Cai, Dong

2011-03-01

383

Field-usable portable analyzer for chlorinated organic compounds  

SciTech Connect

In 1992, a chemical sensor was developed which showed almost perfect selectivity to vapors of chlorinated solvents. When interfaced to an instrument, a chemical analyzer will be produced that has near- absolute selectivity to vapors of volatile chlorinated organic compounds. TRI has just completed the second of a 2-phase program to develop this new instrument system, which is called the RCL MONITOR. In Phase II, this instrument was deployed in 5 EM40 operations. Phase II applications covered clean-up process monitoring, environmental modeling, routine monitoring, health and safety, and technology validation. Vapor levels between 0 and 100 ppM can be determined in 90 s with a lower detection limit of 0.5 ppM using the hand-portable instrument. Based on the favorable performance of the RCL MONITOR, the commercial instrument was released for commercial sales on Sept. 20, 1996.

Buttner, W.J.; Penrose, W.R.; Stetter, J.R.; Williams, R.D.

1996-12-31

384

In situ bioremediation of petroleum hydrocarbon and other organic compounds  

SciTech Connect

From supertanker oil spills to the leaking underground storage tank at the corner gas station, contamination from petroleum hydrocarbon fuels and other organic compounds is an environmental concern that affects nearly every small hamlet and major metropolis throughout the world. Most petroleum hydrocarbons are amenable to biodegradation, and a considerable body of experience has been built up over the past two decades in applying in situ bioremediation to a variety of contaminants in all media. This volume provides a comprehensive guide to the latest technological breakthroughs in both the laboratory and the field, covering such topics as air sparging, co-metabolic biodegradation, treatment of MTBE, real-time control systems, nutrient addition, rapid biosensor analysis, multiphase extraction, and accelerated bioremediation.

Alleman, B.C.; Leeson, A.

1999-11-01

385

In situ bioremediation of petroleum hydrocarbon and other organic compounds  

SciTech Connect

From supertanker oil spills to the leaking underground storage tank at the corner gas station, contamination from petroleum hydrocarbon fuels and other organic compounds is an environmental concern that affects nearly every small hamlet and major metropolis throughout the world. Moreover, the world`s rivers, estuaries, and oceans are threatened by contamination from petroleum leaks and spills. Fortunately, most petroleum hydrocarbons are amenable to biodegradation, and a considerable body of experience has been built up over the past two decades in applying in situ bioremediation to a variety of contaminants in all media. Good progress is being made in terms of developing innovative, cost-effective in situ approaches to bioremediation. This volume provides a comprehensive guide to the latest technological breakthroughs in both the laboratory and the field, covering such topics as air sparging, cometabolic biodegradation, treatment of MTBE, real-time control systems, nutrient addition, rapid biosensor analysis, multiphase extraction, and accelerated bioremediation.

Alleman, B.C.; Leeson, A. [eds.

1999-10-01

386

In situ bioremediation of petroleum hydrocarbon and other organic compounds  

SciTech Connect

From supertanker oil spills to the leaking underground storage tank at the corner gas station, contamination from petroleum hydrocarbon fuels and other organic compounds is an environmental concern that affects nearly every small hamlet and major metropolis throughout the world. Most petroleum hydrocarbons are amenable to biodegradation, and a considerable body of experience has been built up over the past two decades in applying in situ bioremediation to a variety of contaminants in all media. This volume provides a comprehensive guide to the latest technological breakthroughs in both the laboratory and the field, covering such topics as air sparging, co-metabolic biodegradation, treatment of MTBE, real-time control systems, nutrient addition, rapid biosensor analysis, multiphase extraction, and accelerated bioremediation.

Alleman, B.C.; Leeson, A.

1999-01-01

387

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

2013-01-03

388

Volatile Organic Compound Emissions from Dairy Facilities in Central California  

NASA Astrophysics Data System (ADS)

Emissions of volatile organic compounds (VOCs) from dairy facilities are thought to be an important contributor to high ozone levels in Central California, but emissions inventories from these sources contain significant uncertainties. In this work, VOC emissions were measured at two Central California dairies during 2010 and 2011. Isolation flux chambers were used to measure direct emissions from specific dairy sources, and upwind/downwind ambient profiles were measured from ground level up to heights of 60 m. Samples were collected using a combination of canisters and sorbent tubes, and were analyzed by GC-MS. Additional in-situ measurements were made using infra-red photoaccoustic detectors and Diode Laser Absorption Spectroscopy. Temperature and ozone profiles up to 250 m above ground level were also measured using a tethersonde. Substantial fluxes of a number of VOCs including alcohols, volatile fatty acids and esters were observed at both sites. Implications of these measurements for regional air quality will be discussed.

Hasson, A. S.; Ogunjemiyo, S. O.; Trabue, S.; Middala, S. R.; Ashkan, S.; Scoggin, K.; Vu, K. K.; Addala, L.; Olea, C.; Nana, L.; Scruggs, A. K.; Steele, J.; Shelton, T. C.; Osborne, B.; McHenry, J. R.

2011-12-01

389

Solid-phase genotoxicity assay for organic compounds in soil  

SciTech Connect

A genotoxicity assay was developed for samples from environments in which toxic organic compounds are largely sorbed. The assay entails measurement of the rate of mutation of a strain of Pseudomonas putida to rifampicin resistance. The ratio of induced to spontaneous mutants was a function of the concentration of a test mutagen in soil. In studies of the utility of the assay in samples amended with 2-aminofluorene as a test mutagen, the ratio of induced to spontaneous mutants declined with time. The decline paralleled the disappearance of extractable 2-aminofluorene from the soil. The ratio of induced to spontaneous mutants also feel in four other soils with dissimilar properties. The authors suggest that this solid-phase assay is more appropriate for the estimation of genotoxicants sorbed in soil than assays involving extractants or suspensions of soil or sediment samples.

Alexander, R.R.; Chung, N.; Alexander, M. [Cornell Univ., Ithaca, NY (United States)

1999-03-01

390

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

391

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

392

Source characteristics of oxygenated volatile organic compounds and hydrogen cyanide  

NASA Astrophysics Data System (ADS)

Airborne trace gas measurements from Transport and Chemical Evolution over the Pacific (TRACE-P), Pacific Exploratory Mission (PEM)-Tropics B, and Intercontinental Chemical Transport Experiment-North America (INTEX-NA) experiments are analyzed to examine the major source factors contributing to the observed variabilities of oxygenated volatile organic compounds and cyanides. The positive matrix factorization method is applied to coincident measurements of 11 chemicals including CH3OH, CH3COCH3, CH3CHO, C2H2, C2H6, i-C5H12, CO, CH3Cl, and CHBr3. Measurements of HCN and CH3CN are available for TRACE-P and INTEX-NA. We identify major source contributions from the terrestrial biosphere, biomass burning, industry/urban regions, and oceans. Spatial and back trajectory characteristics of these factors are examined. On the basis of TRACE-P and PEM-Tropics B data, we find a factor that explains 80-88% of the CH3OH variability, 20-40% of CH3COCH3, 7-35% of CH3CHO, and 41% of HCN, most likely representing the emissions from terrestrial biosphere. Our analysis suggested that biogenic emissions of HCN may be significant. Cyanogenesis in plants is likely a major emission process for HCN, which was not fully accounted for previously. Larger contributions than previous global estimations to CH3COCH3 and CH3CHO by biomass burning and industry/urban sources likely reflect significant secondary production from volatile organic compound oxidation. No evidence was found for large emissions of CH3COCH3 from the ocean. The oceanic CH3CHO contribution implies large regional variations.

Shim, Changsub; Wang, Yuhang; Singh, Hanwant B.; Blake, Donald R.; Guenther, Alex B.

2007-05-01

393

Source characteristics of oxygenated volatile organic compounds and hydrogen cyanide  

NASA Astrophysics Data System (ADS)

Airborne trace gas measurements from TRACE-P, PEM-Tropics B, and INTEX-NA experiments are analyzed to examine the major source factors contributing to the observed variabilities of oxygenated volatile organic compounds and cyanides. Positive matrix factorization (PMF) is applied to coincident measurements of 11 chemicals including CH3OH, CH3COCH3, CH3CHO, C2H2, C2H6, i-C5H12, CO, CH3Cl, and CHBr3. Measurements of HCN and CH3CN are available for TRACE-P and INTEX-NA. We identify major source contributions from the terrestrial biosphere, biomass burning, industry/urban regions, and oceans. Spatial and backtrajectory characteristics of these factors are examined. Based on TRACE-P and PEM-Tropics B data, we find that the terrestrial biogenic factor explains 80-88% of the CH3OH variability, 20-40% of CH3COCH3, 7-35% of CH3CHO, and 41% of HCN. The biogenic contribution to HCN derived from this analysis is much larger than previous global estimates. Cyanogenesis in plants is likely a major emission process for HCN, not fully accounted for previously. Larger contributions than previous global estimations to CH3COCH3 and CH3CHO by biomass burning and industry/urban sources likely reflect significant secondary production from volatile organic compounds (VOC) oxidation. No evidence was found for large emissions of CH3COCH3 from the ocean. The oceanic CH3CHO contribution implies large regional variations.

Wang, Y.; Shim, C.; Singh, H.; Blake, D.; Guenther, A.

2006-12-01

394

40 CFR Table 1 to Subpart D of... - Volatile Organic Compound (VOC), Content Limits for Architectural Coatings  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Volatile Organic Compound (VOC), Content Limits for...PROGRAMS (CONTINUED) NATIONAL VOLATILE ORGANIC COMPOUND EMISSION STANDARDS FOR CONSUMER AND COMMERCIAL PRODUCTS National Volatile Organic Compound Emission Standards for...

2013-07-01

395

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

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Volatile Organic Compound (VOC) Content Limits for Automobile...PROGRAMS (CONTINUED) NATIONAL VOLATILE ORGANIC COMPOUND EMISSION STANDARDS FOR CONSUMER AND COMMERCIAL PRODUCTS National Volatile Organic Compound Emission Standards for...

2013-07-01

396

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

Code of Federal Regulations, 2010 CFR

...2009-07-01 false Volatile Organic Compound (VOC) Content Limits for Automobile...CONTINUED) NATIONAL VOLATILE ORGANIC COMPOUND EMISSION STANDARDS FOR CONSUMER AND COMMERCIAL PRODUCTS National Volatile Organic Compound Emission Standards for Automobile...

2009-07-01

397

40 CFR Table 1 to Subpart D of... - Volatile Organic Compound (VOC), Content Limits for Architectural Coatings  

Code of Federal Regulations, 2010 CFR

...2009-07-01 false Volatile Organic Compound (VOC), Content Limits for Architectural...CONTINUED) NATIONAL VOLATILE ORGANIC COMPOUND EMISSION STANDARDS FOR CONSUMER AND COMMERCIAL PRODUCTS National Volatile Organic Compound Emission Standards for...

2009-07-01

398

40 CFR Table 1 to Subpart D of... - Volatile Organic Compound (VOC), Content Limits for Architectural Coatings  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Volatile Organic Compound (VOC), Content Limits for Architectural...CONTINUED) NATIONAL VOLATILE ORGANIC COMPOUND EMISSION STANDARDS FOR CONSUMER AND COMMERCIAL PRODUCTS National Volatile Organic Compound Emission Standards for...

2010-07-01

399

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

400

A biogenic volatile organic compound emission inventory for Hong Kong  

NASA Astrophysics Data System (ADS)

Biogenic volatile organic compounds (BVOCs) in the atmosphere react to form ozone and secondary organic aerosols, which deteriorate air quality, affect human health, and indirectly influence global climate changes. The present study aims to provide a preliminary assessment of BVOC emissions in Hong Kong (HKSAR). Thriteen local tree species were measured for their isoprene emission potential. Tree distribution was estimated for country park areas based on field survey data. Plant emission data obtained from measurements and the literature, tree distribution estimation data, land use information, and meteorological data were combined to estimate annual BVOC emissions of 8.6×10 9 g C for Hong Kong. Isoprene, monoterpenes, and other VOCs contributed about 30%, 40%, and 30% of the estimated total annual emissions, respectively. Although hundreds of plant species are found in Hong Kong country parks, the model results indicate that only 10 tree species contribute about 76% of total annual VOC emissions. Prominent seasonal and diurnal variations in emissions were also predicted by the model. The present study lays a solid foundation for future local research, and results can be applied for studying BVOC emissions in nearby southern China and Asian regions that share similar climate and plant distributions.

Tsui, Jeanie Kin-Yin; Guenther, Alex; Yip, Wing-Kin; Chen, Feng

401

Emerging site characterization technologies for volatile organic compounds  

SciTech Connect

A Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) expedited response action (ERA) has been initiated at Hanford Site's 200 West Area for the removal of carbon tetrachloride from the unsaturated soils. In coordination with the ERA, innovative technology demonstrations are being conducted as part of DOE's Volatile Organic Compounds -- Arid Integrated Demonstration in an effort to improve upon baseline technologies. Improved methods for accessing, sampling, and analyzing soil and soil-vapor contaminants is a high priority. Sonic drilling is being evaluated as an alternative to cable-tool drilling, while still providing the advantages of reliability, containment, and waste minimization. Applied Research Associates, Inc. used their cone penetrometer in the 200 West Area to install a permanent soil-gas monitoring probe and to collect soil-gas profile data. However, successful application of this technology will require the development of an improved ability to penetrate coarse gravel units. A Science and Engineering Associates Membrane Instrumentation and Sampling Technique (SEAMIST) system designed for collecting in situ soil samples and air permeability data in between drilling runs at variable depths is being tested in 200 West Area boreholes. Analytical technologies scheduled for testing include supercritical fluid extraction and analysis for non- and semi-volatile organic co-contaminants and an unsaturated flow apparatus developed by Washington State University for the measurement of transport parameters.

Rohay, V.J.; Last, G.V.

1992-05-01

402

Emerging site characterization technologies for volatile organic compounds  

SciTech Connect

A Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) expedited response action (ERA) has been initiated at Hanford Site`s 200 West Area for the removal of carbon tetrachloride from the unsaturated soils. In coordination with the ERA, innovative technology demonstrations are being conducted as part of DOE`s Volatile Organic Compounds -- Arid Integrated Demonstration in an effort to improve upon baseline technologies. Improved methods for accessing, sampling, and analyzing soil and soil-vapor contaminants is a high priority. Sonic drilling is being evaluated as an alternative to cable-tool drilling, while still providing the advantages of reliability, containment, and waste minimization. Applied Research Associates, Inc. used their cone penetrometer in the 200 West Area to install a permanent soil-gas monitoring probe and to collect soil-gas profile data. However, successful application of this technology will require the development of an improved ability to penetrate coarse gravel units. A Science and Engineering Associates Membrane Instrumentation and Sampling Technique (SEAMIST) system designed for collecting in situ soil samples and air permeability data in between drilling runs at variable depths is being tested in 200 West Area boreholes. Analytical technologies scheduled for testing include supercritical fluid extraction and analysis for non- and semi-volatile organic co-contaminants and an unsaturated flow apparatus developed by Washington State University for the measurement of transport parameters.

Rohay, V.J.; Last, G.V.

1992-05-01

403

[Volatile organic compounds (VOCs) emitted from furniture and electrical appliances].  

PubMed

Organic chemicals are widely used as ingredients in household products. Therefore, furniture and other household products as well as building products may influence the indoor air quality. This study was performed to estimate quantitatively influence of household products on indoor air quality. Volatile organic compound (VOC) emissions were investigated for 10 products including furniture (chest, desk, dining table, sofa, cupboard) and electrical appliances (refrigerator, electric heater, desktop personal computer, liquid crystal display television and audio) by the large chamber test method (JIS A 1912) under the standard conditions of 28 degrees C, 50% relative humidity and 0.5 times/h ventilation. Emission rate of total VOC (TVOC) from the sofa showed the highest; over 7900 microg toluene-equivalent/unit/h. Relatively high TVOC emissions were observed also from desk and chest. Based on the emission rates, the impacts on the indoor TVOC were estimated by the simple model with a volume of 17.4 m3 and ventilation frequency of 0.5 times/h. The estimated TVOC increment for the sofa was 911 microg/m3, accounting for almost 230% of the provisional target value, 400 microg/m3. The values of estimated increment of toluene emitted from cupboard and styrene emitted from refrigerator were 10% and 16% of guideline values, respectively. These results revealed that VOC emissions from household products may influence significantly indoor air quality. PMID:21381398

Tanaka-Kagawa, Toshiko; Jinno, Hideto; Furukawa, Yoko; Nishimura, Tetsuji

2010-01-01

404

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

2011-05-23

405

Contributions of individual reactive biogenic volatile organic compounds to organic nitrates above a mixed forest  

NASA Astrophysics Data System (ADS)

Biogenic volatile organic compounds (BVOCs) can react in the atmosphere to form organic nitrates, which serve as NOx (NO + NO2) reservoirs, impacting ozone and secondary organic aerosol production, the oxidative capacity of the atmosphere, and nitrogen availability to ecosystems. To examine the contributions of biogenic emissions and the formation and fate of organic nitrates in a forest environment, we simulated the oxidation of 57 individual BVOCs emitted from a rural mixed forest in northern Michigan. Key BVOC-oxidant reactions were identified for future laboratory and field investigations into reaction rate constants, yields, and speciation of oxidation products. Of the total simulated organic nitrates, monoterpenes contributed ~70% in the early morning at ~12 m above the forest canopy when isoprene emissions were low. In the afternoon, when vertical mixing and isoprene nitrate production were highest, the simulated contribution of isoprene-derived organic nitrates was greater than 90% at all altitudes, with the concentration of secondary isoprene nitrates increasing with altitude. Notably, reaction of isoprene with NO3 leading to isoprene nitrate formation was found to be significant (~8% of primary organic nitrate production) during the daytime, and monoterpene reactions with NO3 were simulated to comprise up to ~83% of primary organic nitrate production at night. Lastly, forest succession, wherein aspen trees are being replaced by pine and maple trees, was predicted to lead to increased afternoon concentrations of monoterpene-derived organic nitrates. This further underscores the need to understand the formation and fate of these species, which have different chemical pathways and oxidation products compared to isoprene-derived organic nitrates and can lead to secondary organic aerosol formation.

Pratt, K. A.; Mielke, L. H.; Shepson, P. B.; Bryan, A. M.; Steiner, A. L.; Ortega, J.; Daly, R.; Helmig, D.; Vogel, C. S.; Griffith, S.; Dusanter, S.; Stevens, P. S.; Alaghmand, M.

2012-11-01

406

Sorption to soil of hydrophobic and ionic organic compounds: measurement and modeling  

Microsoft Academic Search

The sorption of organic compounds to soil, sediments and dissolved organic matter affects the fate of organic compounds. Given the central role of this process in environmental transport, distribution, and (bio)degradation processes, it needs to be well-understood and represented in risk assessment of chemicals in the environment. In this thesis soil-sorption of various organic compounds was studied in order to

Thomas Laurens ter Laak

2005-01-01

407

Chemical compound containing a superoxide scavenger and an organic nitrate or nitrite moiety  

US Patent & Trademark Office Database

Compounds for use in the treatment of heart disease include a superoxide scavenger and an organic nitrate or nitrite moiety. The compounds can be represented by the formula (A)n(B)m, in which A is a superoxide scavenger, B is an organic nitrate or organic nitrite moiety, and n and m are values between 1 and 8. These compounds do not suffer from the problem of patient tolerance that is associated with the use of conventional agents such as organic nitrates.

Zhang; Zhi (London, GB); Naughton; Declan P. (Brighton, GB); Sumi; Yoshihiko (Tokyo, JP); Imaizumi; Atsushi (Tokyo, JP)

2002-02-12

408

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

409

Carbonaceous meteorites as a source of sugar-related organic compounds for the early Earth  

Microsoft Academic Search

The much-studied Murchison meteorite is generally used as the standard reference for organic compounds in extraterrestrial material. Amino acids and other organic compounds important in contemporary biochemistry are thought to have been delivered to the early Earth by asteroids and comets, where they may have played a role in the origin of life. Polyhydroxylated compounds (polyols) such as sugars, sugar

George Cooper; Novelle Kimmich; Warren Belisle; Josh Sarinana; Katrina Brabham; Laurence Garrel

2001-01-01

410

Effect of organic, low-input and conventional production systems on pesticide and growth regulator residues in wheat, potato and cabbage  

Microsoft Academic Search

The Nafferton factorial systems comparison (NFSC) experiments facilitate the investigation of effects of, and interaction between, three production system components - a) rotational position, b) fertility and c) crop protection management - in organic, conventional and low-input crop management systems. This paper presents first results on pesticide and growth regulator residues observed over a period of two years. Residues were

L. Lueck; J. M. Cooper; P. N. Shotton; J. Hajslova; V. Schulzova

2007-01-01

411

Bioactive volatile organic compounds from Antarctic (sponges) bacteria.  

PubMed

Antarctic bacteria represent a reservoir of unexplored biodiversity, which, in turn, might be correlated to the synthesis of still undescribed bioactive molecules, such as antibiotics. In this work we have further characterized a panel of four marine Antarctic bacteria able to inhibit the growth of human opportunistic multiresistant pathogenic bacteria belonging to the Burkholderia cepacia complex (responsible for the 'cepacia' syndrome in Cystic Fibrosis patients) through the production of a set of microbial Volatile Organic Compounds (mVOCs). A list of 30 different mVOCs synthesized under aerobic conditions by Antarctic bacteria was identified by GC-SPME analysis. Cross-streaking experiments suggested that Antarctic bacteria might also synthesize non-volatile molecules able to enhance the anti-Burkholderia activity. The biosynthesis of such a mixture of mVOCs was very probably influenced by both the presence/absence of oxygen and the composition of media used to grow the Antarctic strains. The antimicrobial activity exhibited by Antarctic strains also appeared to be more related to their taxonomical position rather than to the sampling site. Different Bcc bacteria were differently sensitive to the 'Antarctic' mVOCs and this was apparently related neither to the taxonomical position of the different strains nor to their source. The genome sequence of three new Antarctic strains was determined revealing that only P. atlantica TB41 possesses some genes belonging to the nrps-pks cluster. The comparative genomic analysis performed on the genome of the four strains also revealed the presence of a few genes belonging to the core genome and involved in the secondary metabolites biosynthesis. Data obtained suggest that the antimicrobial activity exhibited by Antarctic bacteria might rely on a (complex) mixture of mVOCs whose relative concentration may vary depending on the growth conditions. Besides, it is also possible that the biosynthesis of these compounds might occur through still unknown metabolic pathways. PMID:23619351

Papaleo, Maria Cristiana; Romoli, Riccardo; Bartolucci, Gianluca; Maida, Isabel; Perrin, Elena; Fondi, Marco; Orlandini, Valerio; Mengoni, Alessio; Emiliani, Giovanni; Tutino, Maria Luisa; Parrilli, Ermenegilda; de Pascale, Donatella; Michaud, Luigi; Lo Giudice, Angelina; Fani, Renato

2013-04-22

412

A global model of natural volatile organic compound emissions  

NASA Astrophysics Data System (ADS)

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 resolved spatial grid (0.5°×0.5° latitude/longitude) and generates hourly average emission estimates. Chemical species are grouped into four categories: isoprene, monoterpenes, other reactive VOC (ORVOC), and other VOC (OVOC). NVOC emissions from oceans are estimated as a function of geophysical variables from a general circulation model and ocean color satellite data. Emissions from plant foliage are estimated from ecosystem specific biomass and emission factors and algorithms describing light and temperature dependence of NVOC emissions. Foliar density estimates are based on climatic variables and satellite data. Temporal variations in the model are driven by monthly estimates of biomass and temperature and hourly light estimates. The annual global VOC flux is estimated to be 1150 Tg C, composed of 44% isoprene, 11% monoterpenes, 22.5% other reactive VOC, and 22.5% other VOC. Large uncertainties exist for each of these estimates and particularly for compounds other than isoprene and monoterpenes. Tropical woodlands (rain forest, seasonal, drought-deciduous, and savanna) contribute about half of all global natural VOC emissions. Croplands, shrublands and other woodlands contribute 10-20% apiece. Isoprene emissions calculated for temperate regions are as much as a factor of 5 higher than previous estimates.

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

1995-05-01

413

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

414

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.

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

2012-01-01

415

Solubility of volatile organic compounds in aqueous ammonia solution.  

PubMed

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 303 K and at 0-2.5 mol dm(-3) ammonia concentrations. Ammonia increased the solubility of all VOCs nearly linearly, but to a different extent. The difference in the solubility values in aqueous ammonia solutions (Lmix) compared to pure water (L) is explained on the basis of a Linear Solvation Energy Relationship (LSER) equation made applicable for solvent mixtures, logLmix - logL = x((sNH3 - sH2O)pi2H + (aNH3 - aH2O)Sigma2H + (bNH3 - bH2O)Sigmabeta2H + (vNH3 - VH2O)Vx). sNH3 - sH2O, aNH3 - aH2O, bNH3 - bH2O, vNH3 - vH2O are the differences of solvent parameters, x is the mole fraction, pi2H is the solute dipolarity-polarizability, Sigmaalpha2H is the effective hydrogen bond acidity of the solute, Sigmabeta2H is the effective hydrogen bond basicity of the solute and Vx, the McGowan characteristic volume. The most significant term was v, the phase hydrophobicity. The solubility behavior was explained by the change in structure of the aqueous solution: the presence of ammonia reduces the cavity effect. These findings show that the presence of compounds such as ammonia, frequently observed in environmental waters, especially wastewaters, affect the fugacity of VOCs, having consequences for the environmental partitioning of VOCs and having technical consequences towards wastewater treatment technologies. PMID:15833481

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

2005-05-01

416

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

417

Atmospheric outflow of anthropogenic semivolatile organic compounds from East Asia in Spring 2004  

SciTech Connect

To estimate the emissions of anthropogenic semivolatile organic compounds (SOCs) from East Asia and to identify unique SOC molecular markers in Asian air masses, high-volume air samples were collected on the island of Okinawa, Japan between 22 March and 2 May 2004. Contributions from different source regions (China, Japan, the Koreas, Russia, and ocean/local) were estimated by use of source region impact factors (SRIFs). Elevated concentrations of hexachlorobenzene (HCB), hexachlorcyclohexanes (HCHs), dichlorodiphenyltrichloroethanes (DDTs), and particulate-phase polycyclic aromatic hydrocarbons (PAHs) were attributed to air masses from China. A large proportion of the variation in the current-use pesticides, gas-phase PAHs, and polychlorinated biphenyl (PCB) concentrations was explained by meteorology. Chlordanes showed a technical mixture profile and similar concentrations regardless of source region. {alpha}/{gamma} HCH and trans/cis chlordane ratios did not vary significantly with different source regions and had regional averages of 2.5 {+-} 1.0 and 1.2 {+-} 0.3, respectively. Particulate-phase PAH concentrations were significantly correlated (p value {lt} 0.05) with other incomplete combustion byproduct concentrations, including elemental mercury (Hg{sup 0}), CO, NOx{asterisk}, black carbon, submicrometer aerosols, and SO{sub 2}. By use of measured PAH, CO, and black carbon concentrations and estimated CO and black carbon emission inventories, the emission of six carcinogenic particulate-phase PAHs was estimated to be 1518-4179 metric tons/year for Asia and 778-1728 metric tons/year for China, respectively. These results confirm that East Asian outflow contains significant emissions of carcinogenic particulate-phase PAHs. 39 refs., 3 figs.

Toby Primbs; Staci Simonich; David Schmedding; Glenn Wilson; Dan Jaffe; Akinori Takami; Shungo Kato; Shiro Hatakeyama; Yoshizumi Kajii [Oregon State University, Corvallis, OR (United States). Departments of Chemistry and Environmental and Molecular Toxicology

2007-05-15

418

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

419

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

2012-08-09

420

Controlled exposures to volatile organic compounds in sensitive groups.  

PubMed

Sensitivities to chemicals are characterized by symptoms in multiple organ systems in response to low-level chemical exposures. This paper reviews studies of controlled exposures to odorants and to mixtures of volatile organic compounds. Sensitive subgroups include subjects who met Cullen's 1987 criteria for multiple chemical sensitivity (MCS), Gulf War veterans with chronic fatigue syndrome and chemical sensitivity (CFS/CS), and subjects with specific self-reported sensitivities to methyl terbutyl ether (MTBE) in gasoline (MTBE-sensitive). All studies include comparison of age- and sex-matched healthy controls. Studies of olfaction did not support unusual sensitivity, defined as lower odor thresholds, among MCS subjects; however, a dose-response pattern of symptoms was observed in response to suprathreshold concentrations of phenyl ethyl alcohol. In blinded, controlled exposures to clean air, gasoline, gasoline/11% MTBE, and gasoline/15% MTBE, a threshold effect was observed with MTBE-sensitive subjects reporting significantly increased symptoms to gasoline/15% MTBE exposure. Autonomic arousal (heart and respiration rate; end-tidal CO2) in response to odor of chemical mixtures may mediate symptoms for subjects with generalized chemical sensitivities, but not for those whose sensitivities are confined to specific chemicals. For example, Gulf War veterans with CFS/CS experienced reduced end-tidal CO2 when exposed to diesel fumes, while exposure to MTBE did not produce any psychophysiologic changes in MTBE-sensitive subjects. Controlled olfactory and exposure studies reveal that significant responses can be observed in chemically sensitive subjects even when de-adaptation has not occurred. However, these studies suggest that symptoms are not necessarily accompanied by changes in physiologic arousal. Subject characteristics play a critical role in outcomes. PMID:12000025

Fiedler, N; Kipen, H M

2001-03-01

421

Field-usable portable analyzer for chlorinated organic compounds  

SciTech Connect

Transducer Research, Inc. (TRI) has been working with the DOE Morgantown Energy Technology Center to develop a new chemical monitor based on a unique sensor which responds selectively to vapors of chlorinated solvents. We are also developing field applications for the monitor in actual DOE cleanup operations. During the initial phase, prototype instruments were built and field tested. Because of the high degree of selectivity that is obtained, no response was observed with common hydrocarbon organic compounds such as BTX (benzene, toluene, xylene) or POLs (petroleum, oil, lubricants), and in fact, no non-halogen-containing chemical has been identified which induces a measurable response. By the end of the Phase I effort, a finished instrument system was developed and test marketed. This instrument, called the RCL MONITOR, was designed to analyze individual samples or monitor an area with automated repetitive analyses. Vapor levels between 0 and 500 ppm can be determined in 90 s with a lower detection limit of 0.2 ppm using the hand-portable instrument. In addition to the development of the RCL MONITOR, advanced sampler systems are being developed to: (1) extend the dynamic range of the instrument through autodilution of the vapor and (2) allow chemical analyses to be performed on aqueous samples. When interfaced to the samplers, the RCL MONITOR is capable of measuring chlorinated solvent contamination in the vapor phase up to 5000 ppm and in water and other condensed media from 10 to over 10,000 ppb(wt)--without hydrocarbon and other organic interferences.

Buttner, W.J.; Penrose, W.R.; Stetter, J.R.

1995-12-01

422

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

Microsoft Academic Search

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

Buchmiller

2009-01-01

423

Normal Boiling Points for Organic Compounds: Correlation and Prediction by a Quantitative Structure-Property Relationship  

Microsoft Academic Search

We recently reported a successful correlation of the normal boiling points of 298 organic compounds containing O, N, Cl, and Br with two molecular descriptors.1 In the present study the applicability of these two descriptors for the prediction of boiling points for various other classes of organic compounds was investigated further by employing a diverse data set of 612 organic

Alan R. Katritzky; Victor S. Lobanov; Mati Karelson

1998-01-01

424

Occurrence of Pharmaceuticals, Hormones, and Organic Wastewater Compounds in Pennsylvania Waters, 2006-09.  

National Technical Information Service (NTIS)

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 de...

A. Proctor A. G. Reif C. A. Loper J. K. Crawford R. Manning R. Titler

2012-01-01

425

76 FR 41086 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; Volatile Organic Compound...  

Federal Register 2010, 2011, 2012, 2013

...Volatile Organic Compound Reinforced Plastic Composites Production Operations Rule...compound (VOC) emissions from reinforced plastic composites production operations. This...applies to any facility that has reinforced plastic composites production operations....

2011-07-13

426

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...

427

Tetratopic phenyl compounds, related metal-organic framework materials and post-assembly elaboration  

DOEpatents

Disclosed are tetratopic carboxylic acid phenyl for use in metal-organic framework compounds. These compounds are useful in catalysis, gas storage, sensing, biological imaging, drug delivery and gas adsorption separation.

Farha, Omar K; Hupp, Joseph T

2013-06-25

428

Solutions of Organic Compounds in Fused Alkali Thiocyanates.  

National Technical Information Service (NTIS)

High solubility of polyhydroxy compounds was observed in the fused salts of a mixture of the thiocyanates of potassium and sodium and of potassium thiocyanate alone. The hydroxy compounds are apparently unionized in solution, and the fused-salt solubility...

T. I. Crowell P. Hillery

1964-01-01

429

Predicting flammability of gas mixtures containing volatile organic compounds  

SciTech Connect

One requirement regarding the transportation of transuranic (TRU) radioactive waste containers currently limits the total concentration of potentially flammable volatile organic compounds (VOCs) and flammable gases in the headspace of the waste container. Typical VOCs observed in the drums include aromatic hydrocarbons, ketones, alcohols, cyclohexane, as well as chlorinated hydrocarbons (alkanes and alkenes). Flammable gases, such as hydrogen and methane, may be generated in the containers by radiation-induced decomposition (radiolysis) of water and hydrocarbon waste forms. An experimental program was initiated to identify an accurate means for predicting flammability for gas mixtures containing one or more of the following species: hydrogen, carbon tetrachloride, 1,2-dichloroethane, toluene, or 2-butanone. The lower flammability limits (LFL) of gas mixtures containing equimolar quantity for each species were determined in a 19-liter laboratory flammability chamber using a strong spark ignition source. The group factor contribution method was determined to be more accurate than the LeChatelier method for estimating the LFL for these gas mixtures.

Liekhus, K. [Lockheed Martin Idaho Technologies Co., Idaho Falls, ID (United States). Idaho National Engineering and Environmental Lab.; Zlochower, I. [National Inst. for Occupational Safety and Health, Pittsburgh, PA (United States). Pittsburgh Research Lab.; Djordjevic, S.; Loehr, C. [Benchmark Environmental, Albuquerque, NM (United States)

1997-12-31

430

Identification of nonmethane organic compound emissions from grassland vegetation.  

SciTech Connect

Emissions of nonmethane organic compounds (NMOCs) from grassland vegetation were collected in Summa(reg.sign) passivated stainless-steel canisters with a static enclosure technique and were analyzed by high-resolution gas chromatography with flame ionization and ion trap mass spectrometric detectors. Approximately 40 NMOCs with 6-10 carbon atoms were observed in samples analyzed by high-resolution gas chromatography with the flame ionization detector. Nineteen NMOCs in this molecular weight range (6 aliphatic oxygenates; 1 aromatic hydrocarbon; and 4 acyclic, 5 monocyclic, and 3 bicyclic monoterpenoids) were identified by ion trap mass spectrometry. Mass spectrometry was particularly useful for identifying myrcene and cis-3-hexenylacetate, which coeluted on a fused-silica capillary column coated with a 1-{mu}m-thick film of polydimethylsiloxane. An evaluation of the reactivity of the grassland emissions revealed that the aliphatic oxygenates have lifetimes of a few hours with respect to oxidation by OH and O{sub 3} in the atmosphere. This value is similar to the lifetimes of the bicyclic monoterpenoids. The expected lifetimes of the monoterpenoids with respect to oxidation by NO{sub 3} are only several minutes.

Fukui, Y.; Doskey, P. V.; Environmental Research; NASA Ames Research Center

2000-01-01

431

Analysis of volatile organic compounds released during food decaying processes.  

PubMed

A number of volatile organic compounds (VOCs) including acetone, methyl ethyl ketone, toluene, ethylbenzene, m,p-xylene, styrene, and o- xylene released during food decaying processes were measured from three types of decaying food samples (Kimchi (KC), fresh fish (FF), and salted fish (SF)). To begin with, all the food samples were contained in a 100-mL throwaway syringe. These samples were then analyzed sequentially for up to a 14-day period. The patterns of VOC release contrasted sharply between two types of fish (FF and SF) and KC samples. A comparison of data in terms of total VOC showed that the mean values for the two fish types were in the similar magnitude with 280 ± 579 (FF) and 504 ± 1,089 ppmC (SF), while that for KC was much lower with 16.4 ± 7.6 ppmC. There were strong variations in VOC emission patterns during the food decaying processes between fishes and KC that are characterized most sensitively by such component as styrene. The overall results of this study indicate that concentration levels of the VOCs differed significantly between the food types and with the extent of decaying levels through time. PMID:21541778

Phan, Nhu-Thuc; Kim, Ki-Hyun; Jeon, Eui-Chan; Kim, Uk-Hun; Sohn, Jong Ryeul; Pandey, Sudhir Kumar

2011-05-04

432

A biogenic volatile organic compounds emission inventory for Yunnan Province.  

PubMed

The first detailed inventory for volatile organic compounds (VOC) emissions from vegetation over Yunnan Province, China was presented. The spatially and temporally resolved inventory was developed based on a geographic information system (GIS), remote sensing (RS) data and field measurement data, such as digitized land-use data, normalized difference vegetation index (NDVI) and temperature data from direct real-time measurement. The inventory has a spatial resolution of 5 km x 5 km and a time resolution of 1 h. Urban, agriculture, and natural land-use distributions in Yunnan Province were combined with biomass factors for each land-use category to produce a spatially resolved biomass inventory. A biogenic emission inventory was developed by combining the biomass inventory with hourly emission rates for tree, shrub and ground cover species of the study area. Correcting for environmental factors, including light intensity and temperature, a value of 1.1 x 10(12) gC for total annual biogenic VOC emissions from Yunnan Province, including 6.1 x 10(11) gC for isoprene, 2.1 x 10(11) gC for monoterpenes, and 2.6 x 10(11) gC for OVOC was obtained. The highest VOC emissions occurred in the northwestern, southwestern and north region of Yunnan Province. Some uncertainties were also discussed in this study. PMID:16083102

Wang, Zhi-Hui; Bai, Yu-Hua; Zhang, Shu-Yu

2005-01-01

433

Prediction of boiling points of organic compounds by QSPR tools.  

PubMed

The novel electro-negativity topological descriptors of YC, WC were derived from molecular structure by equilibrium electro-negativity of atom and relative bond length of molecule. The quantitative structure-property relationships (QSPR) between descriptors of YC, WC as well as path number parameter P3 and the normal boiling points of 80 alkanes, 65 unsaturated hydrocarbons and 70 alcohols were obtained separately. The high-quality prediction models were evidenced by coefficient of determination (R(2)), the standard error (S), average absolute errors (AAE) and predictive parameters (Qext(2),RCV(2),Rm(2)). According to the regression equations, the influences of the length of carbon backbone, the size, the degree of branching of a molecule and the role of functional groups on the normal boiling point were analyzed. Comparison results with reference models demonstrated that novel topological descriptors based on the equilibrium electro-negativity of atom and the relative bond length were useful molecular descriptors for predicting the normal boiling points of organic compounds. PMID:23792208

Dai, Yi-Min; Zhu, Zhi-Ping; Cao, Zhong; Zhang, Yue-Fei; Zeng, Ju-Lan; Li, Xun

2013-05-04

434

Superconductivity in Organic Compounds with Pseudo-Triangular Lattice  

NASA Astrophysics Data System (ADS)

We study spin fluctuation (SF) mediated superconductivity (SC) in a half-filled square lattice Hubbard model with the transfer matrices -t between nearest neighbor sites and -t' between a half of next nearest neighbor sites neighboring along only one of the < 1,1 > directions, considering application of this model to organic ?-(BEDT-TTF)2 X compounds. Varying the t'/t value from 0 to 1, one can interpolate between a square and an equilateral triangular lattice, the latter giving frustration to antiferromagnetically (AF) coupled spin systems. Within the fluctuation exchange (FLEX) approximation, we calculate ?(q,?), Tc and the SC order parameter for various model parameter values and find that both AF and SC are suppressed as one approaches the frustration geometry or |(t'/t)-1| \\to 0. The SC phase, however, extends beyond the AF phase boundary fairly close to t'/t = 1 for realistic U/t values. The order parameter is of x^2-y2-type for t'/t < 1 and of xy-type for t'/t > 1.

Kondo, Hisashi; Moriya, Tôru

2004-04-01

435

Predicting the emission rate of volatile organic compounds fromvinyl flooring  

SciTech Connect

A model for predicting the rate at which a volatile organic compound (VOC) is emitted from a diffusion-controlled material is validated for three contaminants (n-pentadecane, n-tetradecane, and phenol) found in vinyl flooring (VF). Model parameters are the initial VOC concentration in the material-phase (C{sub 0}), the material/air partition coefficient (K), and the material-phase diffusion coefficient (D). The model was verified by comparing predicted gas-phase concentrations to data obtained during small-scale chamber tests, and by comparing predicted material-phase concentrations to those measured at the conclusion of the chamber tests. Chamber tests were conducted with the VF placed top side up and bottom side up. With the exception of phenol, and within the limits of experimental precision, the mass of VOCs recovered in the gas phase balances the mass emitted from the material phase. The model parameters (C{sub 0}, K, and D) were measured using procedures that were completely independent of the chamber test. Gas- and material-phase predictions compare well to the bottom-side-up chamber data. The lower emission rates for the top-side-up orientation may be explained by the presence of a low-permeability surface layer. The sink effect of the stainless steel chamber surface was shown to be negligible.

Cox, Steven S.; Little, John C.; Hodgson, Alfred T.

2001-03-01

436

[Volatile organic compounds (VOCs) emitted from large furniture].  

PubMed

Indoor air pollution by volatile organic compounds (VOCs), which may cause a hazardous influence on human being such as sick building (sick house) syndrome, has become a serious problem. In this study, VOCs emitted from nine pieces of home furniture, three sets of dining tables, three sets of chest of drawers and three sofas, were analyzed as potential sources of indoor air pollution by large chamber test method (JIS A 1911). Based on the emission rates of total VOC (TVOC), the impacts on the indoor TVOC was estimated by the sample model with a volume of 20 m3 and ventilation frequency of 0.5 times/h. The estimated TVOC increment values were exceeded the provisional target value for indoor air (400 microg/m3) in three sets of dining tables, one set of chest of drawer and one sofa. The estimated increment of formaldehyde were exceeded the guideline value (100 microg/m3) in one set of dining table, two sets of chest of drawers and one sofa. These results revealed that VOC emissions from furniture may influence significantly indoor air quality. Also, in this study, to establish the alternative method for large chamber test methods, emission rates from representative three parts of furniture unit were evaluated using the small chamber and emission rate from full-sized furniture was predicted. Emission rates of TVOC and formaldehyde predicted by small chamber test were 3-46% and 6-252% of the data obtained using large chamber test, respectively. PMID:22259846

Tanaka-Kagawa, Toshiko; Furuta, Mitsuko; Shibatsuji, Masayoshi; Jinno, Hideto; Nishimura, Tetsuji

2011-01-01

437

Advanced heat pump for the recovery of volatile organic compounds  

SciTech Connect

Emissions of Volatile Organic Compounds (VOC) from stationary industrial and commercial sources represent a substantial portion of the total US VOC emissions. The Toxic-Release Inventory'' of The US Environmental Protection Agency estimates this to be at about 3 billion pounds per year (1987 estimates). The majority of these VOC emissions are from coating processes, cleaning processes, polymer production, fuel production and distribution, foam blowing,refrigerant production, and wood products production. The US Department of Energy's (DOE) interest in the recovery of VOC stems from the energy embodied in the recovered solvents and the energy required to dispose of them in an environmentally acceptable manner. This Phase I report documents 3M's work in close working relationship with its subcontractor Nuclear Consulting Services (Nucon) for the preliminary conceptual design of an advanced Brayton cycle heat pump for the recovery of VOC. Nucon designed Brayton cycle heat pump for the recovery of methyl ethyl ketone and toluene from coating operations at 3M Weatherford, OK, was used as a base line for the work under cooperative agreement between 3M and ODE. See appendix A and reference (4) by Kovach of Nucon. This cooperative agreement report evaluates and compares an advanced Brayton cycle heat pump for solvent recovery with other competing technologies for solvent recovery and reuse. This advanced Brayton cycle heat pump is simple (very few components), highly reliable (off the shelf components), energy efficient and economically priced.

Not Available

1992-03-01

438

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

439

Syntheses, characterizations and properties of organic-inorganic perovskite compounds  

NASA Astrophysics Data System (ADS)

The purpose of this work is to synthesize and characterize a family of organic-based tin(II) iodide layered perovskites---[H3N(CH 2)mNH3](CH3NH 3)n-1SnnI 3n+1 (n = 1--4, m = 4--6, 7, 8, 9, 12). The crystalline hybrid compounds were prepared by crystallization from acidic HI solutions (Method I) and by gel techniques (Method II). The crystal structures of the resulting products were characterized by single crystal X-ray diffraction and IR spectroscopy. Their electronic structure and chemical bonding were investigated by UV-VIS reflectance spectroscopy, 4-probe resistivity measurements, and electronic band structure calculations. Normal flat single-layered perovskites with a variety of alkyldiamines---[H 3N(CH2)mNH3]SnI 4 (m = 4--6, 8, 9), were obtained from Method I, while those with longer hydrocarbon chains, e.g. [H3N(CH2)12NH 3]SnI4, were synthesized by Method II. The typical unit cell of these compounds consist of a 2-dimensional inorganic anion [SnI4 2-]---mono-layered perovskite sheets, and layers of [H 3N(CH2)mNH3] 2+ cations packed between the inorganic sheets. An unexpected corrugated anion sheet, [SnI4]2-, was also observed, for the first time, in alpha-[H3N(CH2)SNH3]SnI 4. The multi-layered perovskite hybrid compounds---the double-layered [H3N(CH2)SNH3](CH3NH3)SnI 7, the triple-layered perovskites [H3N(CH 2)4NH3](CH3NH3)2Sn 3I10, and [H3N(CH2)6NH 3](CH3NH3)2Sn3I10, and a quadruple-layered [H3N(CH2)SNH3](CH 3NH3)3Sn4I13 were obtained in polycrystalline and single crystalline forms. Single crystal X-ray diffraction, electronic band structure calculations, and electronic resistivity measurements were performed on representative members of the family of hybrid perovskites. Attempts to introduce nonprimary amines into the layered perovskite structures resulted in the preparation of 2,2'-biimidazolium tin iodide---[NH(CH)2NHC]2SnI4 and morpholinium tin iodide[O(CH2)2NH2(CH2) 2]2SnI4. These are the first reports of nonprimary amine-based layered perovskite structures. Their crystal structures reveal significant deviations from typical layered perovskite structures, characterized by severely distorted SnI6 octahedral units. Electronic band structure calculations, using the tight-binding approach, reveal significant interplay of the stereoactivity of the Sn(II) lone-pairs with the onset of hypervalent secondary bonding in morpholinium tin iodide. Thus, the seemingly layered perovskite structure of morpholinium tin iodide exhibits a one-dimensional bonding character. Two unprecedented three-dimensional (3-D) defect perovskite compounds, [H3N(CH2)7NH3]2Sn 3I10 and [H3N(CH2)7NH 3]8(H3NCH3)2Sn(IV)Sn(II) 12I46 were prepared. Their novel 3-D structures can be derived from the ordered arrangement of vacancies on the metal and anion sites of the perovskite. These defect perovskite structures are unique to metal oxide and halide chemistry.

Guan, Jun

2001-12-01

440

Dispersion and toxicity to non-target aquatic organisms of pesticides used to treat sea lice on salmon in net pen enclosures.  

PubMed

Pesticides are used extensively in the finfish aquaculture industry to control sea lice infestations on farmed salmon. The most prevalent method of use is to enclose a net pen with an impervious tarpaulin and mix a pesticide solution within that enclosure. After treatment for short periods (1 h) the pesticide solution is released to the environment. Concerns have been raised that there is a potential risk to non-target aquatic organisms from those releases. The fate of dispersing pesticide solutions was measured after six simulated treatments in the Lower Bay of Fundy, New Brunswick. Three simulated treatments were done with azamethiphos and three with cypermethrin. Rhodamine dye was added to all pesticide solutions in order to facilitate tracking of the dispersing plume through real-time measurements of dye concentrations by a flow-through fluorometer coupled with a differential global positioning system (DGPS). Water samples were obtained from within the plumes at various times after release and analysed for pesticide content and toxicity to a benthic amphipod Eohaustorius estuaris. Dye concentrations were detectable for time periods after release which varied from 2 to 5.5 h. Distances travelled by the dye patches ranged from 900 to 3000 m and the dye concentrations at the final sampling period were generally 1/200-1/3000 the pre-release concentrations and cypermethrin concentrations were generally 1/1000-1/2000 the pre-release concentrations. Cypermethrin concentrations in water samples were closely correlated with dye concentrations, indicating that dye analyses were an accurate surrogate for cypermethrin concentrations. Most samples taken after the releases of azamethiphos were not toxic to test organisms in 48 h exposures and none were beyond 20 min post-release. By contrast, almost all samples taken after the release of cypermethrin, even up to 5-h post-release, were toxic. Data indicate the potential to cause toxic effects over areas of hectares from a single release of cypermethrin. PMID:11468921

Ernst, W; Jackman, P; Doe, K; Page, F; Julien, G; Mackay, K; Sutherland, T

2001-06-01