WorldWideScience

Sample records for chlorinated hydrocarbon pesticides

  1. Chlorinated hydrocarbon pesticides and polychlorinated biphenyls in sediment cores from San Francisco Bay

    Science.gov (United States)

    Venkatesan, M.I.; De Leon, R. P.; VanGeen, A.; Luoma, S.N.

    1999-01-01

    Sediment cores of known chronology from Richardson and San Pablo Bays in San Francisco Bay, CA, were analyzed for a suite of chlorinated hydrocarbon pesticides and polychlorinated biphenyls to reconstruct a historic record of inputs. Total DDTs (DDT = 2,4'- and 4,4'-dichlorodiphenyltrichloroethane and the metabolites, 2,4'- and 4,4'-DDE, -DDD) range in concentration from 4-21 ng/g and constitute a major fraction (> 84%) of the total pesticides in the top 70 cm of Richardson Bay sediment. A subsurface maximum corresponds to a peak deposition date of 1969-1974. The first measurable DDT levels are found in sediment deposited in the late 1930's. The higher DDT inventory in the San Pablo relative to the Richardson Bay core probably reflects the greater proximity of San Pablo Bay to agricultural activities in the watershed of the Sacramento and San Joaquin rivers. Total polychlorinated biphenyls (PCBs) occur at comparable levels in the two Bays (inventories in San Pablo Bay are about a factor of four higher in the last four decades than in Richardson Bay, suggesting a distribution of inputs not as strongly weighed towards the upper reaches of the estuary as DDTs. The shallower subsurface maximum in PCBs compared to DDT in the San Pablo Bay core is consistent with the imposition of drastic source control measures four these constituents in 1970 and 1977 respectively. The observed decline in DDT and PCB levels towards the surface of both cores is consistent with a dramatic drop in the input of these pollutants once the effect of sediment resuspension and mixing is taken into account.

  2. Chlorination of organophosphorus pesticides in natural waters.

    Science.gov (United States)

    Acero, Juan L; Benítez, F Javier; Real, Francisco J; González, Manuel

    2008-05-01

    Unknown second-order rate constants for the reactions of three organophosphorus pesticides (chlorpyrifos, chlorfenvinfos and diazinon) with chlorine were determined in the present study, and the influence of pH and temperature was established. It was found that an increase in the pH provides a negative effect on the pesticides degradation rates. Apparent second-order rate constants at 20 degrees C and pH 7 were determined to be 110.9, 0.004 and 191.6 M(-1) s(-1) for chlorpyrifos, chlorfenvinfos and diazinon, respectively. A higher reactivity of chlorine with the phosphorothioate group (chlorpyrifos and diazinon) than with the phosphate moiety (chlorfenvinfos) could explain these results. Intrinsic rate constant for the elementary reactions of chlorine species with chlorpyrifos and diazinon were also calculated, leading to the conclusion that the reaction between hypochlorous acid and the pesticide is predominant at neutral pH. The elimination of these pesticides in surface waters was also investigated. A chlorine dose of 2.5 mg L(-1) was enough to oxidize chlorpyrifos and diazinon almost completely, with a formation of trihalomethanes below the EU standard for drinking water. However, the removal of chlorfenvinfos was not appreciable. Therefore, chlorination is a feasible option for the removal of organophosphorus pesticides with phosphorothioate group during oxidation and disinfection processes, but not for the elimination of pesticides with phosphate moiety.

  3. Hydrochloric acid recycling from chlorinated hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Sowieja, D. [Sulzer Escher Wyss GmbH, Ravensburg (Germany); Schaub, M. [Sulzer Chemtech Ltd., Winterthur (Switzerland)

    1993-12-31

    Chlorinated hydrocarbons present a major ecological hazard since most of them are only poorly biodegradable. Incineration is an economical process for their destruction, however the usually recovered sodium or calcium chlorides do not present a value and their disposal may even be very costly. Recovery of hydrochloric acid may therefore present an economical solution, mainly were large quantities of highly chlorinated compounds can be processed (author) 6 refs., 4 figs., 1 tab.

  4. Behavioral toxicology, risk assessment, and chlorinated hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Evangelista de Duffard, A.M.; Duffard, R. [Laboratorio de Toxicologia Experimental, Santa Fe (Argentina)

    1996-04-01

    Behavioral end points are being used with greater frequency in neurotoxicology to detect and characterize the adverse effects of chemicals on the nervous system. Behavioral measures are particularly important for neurotoxicity risk assessment since many known neurotoxicants do not result in neuropathology. The chlorinated hydrocarbon class consists of a wide variety of chemicals including polychlorinated biphenyls, clioquinol, trichloroethylene, hexachlorophene, organochlorine insecticides (DDT, dicofol, chlordecone, dieldrin, and lindane), and phenoxyherbicides. Each of these chemicals has effects on motor, sensory, or cognitive function that are detectable using functional measures such as behavior. Furthermore, there is evidence that if exposure occurs during critical periods of development, many of the chlorinated hydrocarbons are developmental neurotoxicants. Developmental neurotoxicity is frequently expressed as alterations in motor function or cognitive abilities or charges in the ontogeny of sensorimotor reflexes. Neurotoxicity risk assessment should include assessments of the full range of possible neurotoxicological effects, including both structural and functional indicators of neurotoxicity. 121 refs., 1 tab.

  5. Radiolytic degradation of chlorinated hydrocarbons in water

    International Nuclear Information System (INIS)

    Radiolytic degradation of chlorinated hydrocarbons (chloroform, trichloroethylene, and tetrachloroethylene) in water was carried out. Water solutions of the chlorinated hydrocarbons with different concentrations were irradiated with γ rays. Concentrations of methane, ethane, CO, CO2, H2, and O2 after the irradiation were determined by gas chromatography. Concentration of chloride ion in the irradiated sample was determined by ion chromatography. Experimental results show that radiolytic degradation of the chlorinated hydrocarbon increased with the radiation dose. Methane, ethane, CO2, H2, and Cl- concentrations increased with the radiation dose and the sample concentration. On the other hand, O2 concentration decreased with the radiation dose and the sample concentration. When sample concentration was high, dissolved oxygen might be not enough for converting most of the C atoms in the sample into CO2. This resulted in a low decomposition ratio. Addition of H2O2 as an oxygen resource could increase the decomposition ratio greatly. Furthermore, gas chromatography-mass spectroscopy was applied to identify some intermediates of the radiolytic dehalogenation. Radiolytic degradation mechanisms are also discussed. (author)

  6. Catalytic hydrogen-chlorine exchange between chlorinated hydrocarbons under oxygen-free conditions

    NARCIS (Netherlands)

    van der Heijden, A.W.A.M.; Podkolzin, S.G.; Jones, M.E.; Bitter, J.H.; Weckhuysen, B.M.

    2008-01-01

    Chlorinated hydrocarbons (CHCs) remain important industrial chemical intermediates and solvents, especially for the exploration of the potential of La-based materials for the conversion of chlorinated waste compounds.[1] The production of industrially important CHCs frequently occurs with concurrent

  7. Separation of chlorinated hydrocarbons and organophosphorus,pyrethroid pesticides by silicagel fractionation chromatography and their simultaneous determination by GC-MS

    Institute of Scientific and Technical Information of China (English)

    WANG Li-gang; JIANG Xin; WANG Fang; BIAN Yong-rong; Stephan Forster; Dieter Martens

    2004-01-01

    A silicagel fractionation procedure for environmental sample extracts, which separates chlorinatedhydrocarbons(CHCs) and organophosphorus, pyrethroid pesticides into two groups for subsequent instrumentalanalysis, was developed in this study. This method was achieved by optimizing the fraction cut-off volume of elutionand different solvents. Using fully activated silica gel and cut-off CHCs collection after 10 mi 10% dichloromethane(DCM) in n-hexane passing through the column resulted in satisfactory separation of CHCs and organophosphorus,pyrethroid pesticides. This procedure had a higher reliability for CHCs than for organophosphorus, pyrethroidpesticides, because there is a relatively reliable recovery for CHCs. This approach is less expensive due to reducingsample pre-treatment time and solvent consumption.

  8. Anaerobic Degradation of Chlorinated Hydrocarbons in Groundwater Aquifers or "Chlorinated Hydrocarbon Degradation"

    OpenAIRE

    Nielsen, R. Brent; Jay D Keasling

    1997-01-01

    Groundwater contamination by chlorinated hydrocarbons, such as tetrachloroethene (PCE) or trichloroethene (TCE), is a major concern throughout the United States. A developing strategy for the remediation of PCE and TCE contaminated aquifers is anaerobic biodegradation. From a TCE contaminated groundwater site, microorganisms were enriched with the ability to anaerobically convert PCE and TCE completely to ethene. Kinetic studies performed with this culture showed that degradation of PCE, TCE...

  9. Chlorinated organic pesticides in marketed food: Barcelona, 2001-06

    International Nuclear Information System (INIS)

    This paper reports concentration levels of 22 chlorinated organic compounds (both primary compounds and metabolites) in food marketed in the city of Barcelona (Catalonia, Spain) in 2001-06. Samples included meat products, fish and seafood, eggs, milk and dairy, vegetal oils, cereal products and derivates, vegetables, fresh fruits, dry fruits, spices, formula and baby food, tea and wine. Levels of chlorinated organic compounds were determined by gas chromatography with selective detectors: electron capture (ECD), flame photometric (FPD) and confirmation with mass-spectrometry. Chlorinated organic pesticides were detected in 7 of the 1,484 samples analyzed in the 2001-06 period (0.5%): 1 dairy product, 1 fruit, 1 olive oil and 4 vegetables. Specific pesticides detected are lindane and endosulfan α, β or sulphate. A decrease in both the proportion of samples with detectable residues and in the variety of chlorinated pesticides found is visible when comparing these results with those of the previous 1989-2000 period. These results suggest the gradual disappearance of regulated chlorinated organic pesticides as a consequence of the growing worldwide implementation of current regulatory agreements

  10. Transformation of Chlorinated Hydrocarbons on Synthetic Green Rusts

    Science.gov (United States)

    Green rusts (GRs) are layered double hydroxides that contain both ferrous and ferric ions in their structure. GRs can potentially serve as a chemical reductant for degradation of chlorinated hydrocarbons. GRs are found in zerovalent iron based permeable reactive barriers and in c...

  11. Riverine input of chlorinated hydrocarbons in the coastal pollution

    Digital Repository Service at National Institute of Oceanography (India)

    Sarkar, A.; Everaarts, J.M.

    of various chlorinated hydrocarbons. It deals with an in-depth analysis of pollution of the coastal ecosystem around the Netherlands, U.K. and Germany due to inputs of contaminants from the rivers namely, Elbe, Weser, Ems Ijssel, Rhine, Meuse, Scheldt, Thames...

  12. Electrochemical reduction characteristics and the mechanism of chlorinated hydrocarbons at the copper electrode

    Institute of Scientific and Technical Information of China (English)

    XU Wenying; GAO Tingyao; ZHOU Rongfeng; MA Lumin

    2007-01-01

    The electrochemical reduction characteristies of chlorinated hyrdrocarbons were investigated by cyclic voltammetry technique.The reduction mechanism and activity of the chlorinated hydrocarbons at the copper electrode were explored.The relationship between the structure of chlorinated hydrocarbons and their reductive activity were discussed.The experimental results showed that chlorinated alkanes and a portion of chlorinated aromatic hydrocarbons could be reduced directly at the copper electrode.However,chlorinated aromatic hydrocarbons were not easy to reduce at the copper electrode.The results provided a theoretical basis for the catalyzed iron inner electrolysis method.

  13. Environmental Behavior, Sources, and Effects of Chlorinated Polycyclic Aromatic Hydrocarbons

    Directory of Open Access Journals (Sweden)

    Takeshi Ohura

    2007-01-01

    Full Text Available The environmental sources and behaviors of chlorinated 2- to 5-ring polycyclic aromatic hydrocarbons (ClPAHs. ClPAHs are ubiquitous contaminants found in urban air, vehicle exhaust gas, snow, tap water, and sediments. The concentrations of ClPAHs in each of these environments are generally higher than those of dioxins but markedly lower than the concentrations of the parent compounds, PAHs. Environmental data and emission sources analysis for ClPAHs reveal that the dominant process of generation is by reaction of PAHs with chlorine in pyrosynthesis. This secondary reaction process also occurs in aquatic environments. Certain ClPAHs show greater toxicity, such as mutagenicity and aryl hydrocarbon receptor activity, than their corresponding parent PAHs. Investigation of the sources and environmental behavior of ClPAHs is of great importance in the assessment of human health risks.

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

    International Nuclear Information System (INIS)

    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. -- Highlights: •Pesticides were measured in streams in organic, integrated, and conventional farms. •Higher concentrations of some pesticides were found in conventional sites. •Streams in organic and integrated sites were not pesticide free. •Mean pesticide concentrations were below the recommended toxicity thresholds. -- Higher concentrations of several chlorinated pesticides were found in conventional farms; however, organic and integrated practices were not pesticide-free

  15. Chlorinated hydrocarbons in coastal lagoons of the pacific coast of Nicaragua.

    Science.gov (United States)

    Carvalho, F P; Montenegro-Guillen, S; Villeneuve, J; Cattini, C; Bartocci, J; Lacayo, M; Cruz, A

    1999-02-01

    A screening for persistent chlorinated hydrocarbons was carried out in December 1995 in the main coastal lagoons on the Pacific side of Nicaragua, where most of the country's agriculture and pesticide use has been taking place for decades. Results for a wide range of organochlorine pesticides in lagoon sediments show levels that generally were very low in Estero Real, Estero Padre Ramos, and estuary of San Juan del Sur. For example, total DDTs in these lagoons averaged 4.5 +/- 3.4 ng g-1 dry weight, which may be considered a baseline level for the region. Other compounds such as HCHs, BHC, endosulfan, heptachlor, endrin, toxaphene, and aroclors were present in concentrations even lower, generally below 1 ng g-1 dry weight. However, sediments of the Esteros Naranjo-Paso Caballos system at Chinandega district contained pesticide residues in much higher levels, attaining maximum values of 1,420 ng g-1 and 270 ng g-1 dry weight, respectively, for toxaphene and total DDTs. Other compounds such as aroclors, chlordane, endosulfan, and dieldrin were also present in the sediments of this lagoon system, but in lower concentrations. The very high concentrations of toxaphene and DDTs in this lagoon are a result of the intensive use of these pesticides in cotton growing in the district of Chinandega. Due to the long environmental half-lives of these compounds (t(1/2) > 10 years in temperate soils), their concentrations in lagoon sediments will likely remain high for years to come. Based on these results, the development of the new shrimp farming activities in the Pacific coastal lagoons should be restricted to selected areas.

  16. Solidification of sediment contaminated with volatile chlorinated hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Schwarz, E.J. [Anchor QEA LLC, Portland, OR (United States)

    2010-07-01

    A series of bench-scale treatability tests were used to evaluate the effectiveness of various solidification reagents in treating sediments contaminated with high concentrations of chlorinated hydrocarbons. The effectiveness of Portland cement, cement kiln dust, lime kiln dust, fly ash, and a combination of silica and lime were was assessed relative to their ability to reduce the leaching of contaminants, increase the strength of the contaminated sediment, and reduce the hydraulic conductivity of the sediments. The aim of the study was to develop a design for treating sediments in a stagnant water body located on the grounds of an industrial facility. The sediments were predominantly fine-grained and high in organic content. Preliminary tests identified Portland cement and the silica and lime mixture as achieving the desired strength and resistance to leaching. The solidification reagents were used to solidify more than 11,000 cubic yards of sediment with a mixture of 2 fly ashes. The full-scale solidification project surpassed the required standards for strength and permeability. 10 refs., 4 tabs., 3 figs.

  17. Use of chlorination, ozonization and GAC adsorption to eliminate triazine pesticides in water supplies

    International Nuclear Information System (INIS)

    This study is focused on the research made between Facsa and Universidad de Zaragoza (Spain) related to the oxidation techniques application by chlorination and ozonization, and their combination with granular activated carbon (GAC) adsorption of mineral origin, in order to control triazine pesticides in water supplies. Experiments are carried out is a pilot plant. Although the chlorination or ozonization can partially degrade pesticides under study (atrazine, simazine, terbutilazine and bromacil), their passing through an adsorption column with GAC mineral, achieves their total removal when their initial concentrations are about 500 ng/l. These concentrations are obtained by fortification of studied sample. (Author) 9 refs

  18. Polynuclear aromatic and chlorinated hydrocarbons in mussels from the coastal zone of Ushuaia, Tierra del Fuego, Argentina.

    Science.gov (United States)

    Amin, Oscar A; Comoglio, Laura I; Sericano, José L

    2011-03-01

    Mussels (Mytilus edulis chilensis) were collected from 12 coastal locations in Ushuaia Bay, Argentina, and the surrounding area in October 1999 and again in October 2003. Concentrations of polynuclear aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and selected chlorinated pesticides were determined to assess the impact of a fast-growing population in the area. Total PAH concentrations ranged from 2.24 to an extremely high concentration of 2,420 µg/g lipid measured in mussels collected near an oil jetty used to discharge to shore storage tanks. The composition of PAHs in these samples indicates that the source of these compounds inside Ushuaia Bay is predominantly petrogenic, with some pyrogenic background, whereas mostly pyrogenic-related PAHs were evident in areas outside the bay. Total concentrations of PCBs ranged between 12.8 and 8,210 ng/g lipid, with the highest concentration, detected inside Ushuaia harbor, representing a 10-fold increase when compared with historical data. Chlorinated pesticides were detected at comparatively lower concentrations, with 4-4'- 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene being the most common. The aggressive increase in population and related activities observed in the city of Ushuaia over the last two decades might have affected the environmental quality of the local bay. Moreover, the oceanographic and atmospheric conditions existing in Ushuaia Bay and surrounding areas may favor the accumulation and long-term presence of these organic pollutants in all compartments of this fragile environment. PMID:21128271

  19. Formation of phosgene during welding activities in an atmosphere containing chlorinated hydrocarbons.

    Science.gov (United States)

    Nieuwenhuizen, M S; Groeneveld, F R

    2000-01-01

    The formation of phosgene During welding activities in an atmosphere containing chlorinated hydrocarbons was investigated. Four different chlorinated hydrocarbons were studied under laboratory conditions. Results are presented as time-averaged phosgene concentration in a total volume of 250 L of air being purged through a 52-L reaction vessel during 20 min. It was found that the formation of phosgene was in the order dichloromethane smoke particles and because of possible nonhomogeneous dispersion of phosgene around the workers. In the case of dichloromethane and carbon tetrachloride the short-term maximum allowable concentration (MAC) of phosgene was not attained at the respective MAC values of the chlorinated hydrocarbons themselves. In the case of trichloroethylene and Freon-22, however, the short-term MAC-value of phosgene was attained even when the concentration was still much below the respective MAC-values.

  20. Heavy metal and chlorinated hydrocarbon residues in California sea loins (Zalophus californianus californianus)

    Energy Technology Data Exchange (ETDEWEB)

    Buhler, D.R.; Claeys, R.R.; Mate, B.R.

    1975-12-01

    Samples of various tissues and organs from healthy California sea lions (Zalophus californianus californianus) and sick animals (apparently with leptospirosis) collected along the central Oregon coast in 1970, 1971, and 1973 were analyzed for total mercury, methylmercury, cadmium, and chlorinated hydrocarbons. Maximum mercury concentrations of 74 to 170 ppM occurred in sea lion liver, but only 1.6 to 3.7 percent of this was present as methylmercury. Cadmium was concentrated primarily in the kidney which contained 7.2 to 12.0 ppM of the metal. Chlorinated hydrocarbon residues in sea lion fat ranged between 253 to 475 ppM DDE, and 21.2 and 34.1 ppM PCB. Although mercury, cadmium, and chlorinated hydrocarbon residues in some of the sick sea lions were significantly higher than those present in healthy animals, it is not possible to relate these differences to the onset of leptospirosis.

  1. Polyethylene as a source of artifacts in the paper chromatography of chlorinated hydrocarbon insecticides

    Science.gov (United States)

    Van Valin, C.C.; Kallman, B.J.; O'Donnell, J.J

    1963-01-01

    The introduction of artifacts from vessels, materials, and chemicals is a serious problem in the study of pesticide residues. It is therefore of interest to record findings that polyethylene wash bottles contain substances soluble in organic solvents and reactive with the silver nitrate chromogenic spray commonly employed in the paper chromatographic analysis of chlorinated organic insecticides.

  2. Influence of organophosphorus pesticides on peroxidase and chlorination activity of human myeloperoxidase.

    Science.gov (United States)

    Lazarević-Pašti, Tamara; Momić, Tatjana; Radojević, Miloš M; Vasić, Vesna

    2013-09-01

    Inhibitory effects of five organophosphorus pesticides (diazinon, malathion, chlorpyrifos, azinphos-methyl and phorate) and their oxo-analogs on human myeloperoxidase (MPO) activity were investigated. While inspecting separately peroxidase and chlorination activity, it was observed that investigated OPs affect peroxidase activity, but not chlorination activity. Among investigated pesticides, malathion and malaoxon have showed the highest power to inhibit MPO peroxidase activity with IC50 values of the order of 3×10(-7) and 5×10(-9) M, respectively. It was proposed that inhibition trend is rendered by molecular structure which invokes steric hindrance for OPs interaction with MPO active center responsible for peroxidase activity. In addition, it was concluded that physiological function of MPO is not affected by any of the investigated OPs. PMID:25149236

  3. Application of Pseudomonas sp. strain DCA1 for the removal of chlorinated hydrocarbons

    NARCIS (Netherlands)

    Hage, J.C.

    2004-01-01

    The large-scale application of chlorinated aliphatic hydrocarbons (CAHs) has resulted in many cases of groundwater contamination. Contaminated groundwater can be remediated by pump-and-treat: the groundwater is pumped to the surface and treated. The groundwater can be treated in bioreactors, in whic

  4. Kinetics of Chlorinated Hydrocarbon Degradation by Methylosinus trichosporium OB3b and Toxicity of Trichloroethylene

    NARCIS (Netherlands)

    Oldenhuis, Roelof; Oedzes, Johannes Y.; Waarde, Jacob J. van der; Janssen, Dick B.

    1991-01-01

    The kinetics of the degradation of trichloroethylene (TCE) and seven other chlorinated aliphatic hydrocarbons by Methylosinus trichosporium OB3b were studied. All experiments were performed with cells grown under copper stress and thus expressing soluble methane monooxygenase. Compounds that were re

  5. In situ bioremediation of petroleum hydrocarbons and chlorinated hydrocarbons: Three case studies

    International Nuclear Information System (INIS)

    In situ biodegradation of organic contaminants is one of the most cost-effective means of site remediation. This method has proven successful in soils, ground water, and slurries. Bacteria capable of degrading organic contaminants within an aquifer include many species from a wide spectrum of genera, e.g. Pseudomonas, Corynebacterium, Bacillus, etc. In most cases, a mixture of bacterial strains is required to completely oxidize a complex organic contaminant. Each strain of an organism may target a specific compound, working together with other organisms to ultimately degrade each intermediate until complete degradation, also known as mineralization, occurs. One or more of the following mechanisms are utilized by bacteria for organic chemical degradation: (1) aerobic, (2) anaerobic, and (3) co-metabolic. During aerobic oxidation of organic chemicals, bacteria utilize the pollutant as an electron and hydrogen source and oxygen acts as the electron and hydrogen acceptor, resulting in water. As the bacterial enzymes cleave the compound, oxidized products are produced along with energy for the reaction to proceed. This is the most rapid and widely utilized mechanism. Dehalogenation occurs under aerobic, or perhaps more often, under anoxic conditions. This process occurs in the presence of alternate electron acceptors and replaces chlorine with hydrogen. The mechanism of co-metabolism can be aerobic or anaerobic, but is more often aerobic. This process requires a separate energy source for the bacterial cell because the pollutant is not utilized as an energy source. The role of bioremediation in site remediation is demonstrated below by three case studies: (1) a refinery, (2) a municipal landfill and (3) a pesticide formulation plant

  6. Assessing breeding potential of peregrine falcons based on chlorinated hydrocarbon concentrations in prey

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, J.E. [Canadian Wildlife Service, Pacific Wildlife Research Centre, 5421 Robertson Rd., RR no. 1, Delta, British Columbia, V4K 3N2 (Canada)]. E-mail: john.elliott@ec.gc.ca; Miller, M.J. [Iolaire Ecological Consulting, 7899 Thrasher St., Mission, British Columbia, V2V 5H3 (Canada); Wilson, L.K. [Canadian Wildlife Service, Pacific Wildlife Research Centre, 5421 Robertson Rd., RR no. 1, Delta, British Columbia, V4K 3N2 (Canada)

    2005-03-01

    Peregrine falcons (Falco peregrinus) now breed successfully in most areas of North America from which they were previously extirpated. The loss during the mid-part of the last century of many of the world's peregrine populations was largely a consequence of impaired reproduction caused by the effects of DDE on eggshell quality and embryo hatchability. Population recovery has been attributed to re-introduction efforts, coupled with regulatory restrictions on the use of organochlorine pesticides. Peregrines have not returned to breed in some areas, such as the Okanagan Valley of British Columbia. That region has been extensively planted in fruit orchards which were treated annually with DDT during the early 1950s to the 1970s. Ongoing contamination of avian species, including potential peregrine prey, inhabiting orchards has been documented. In response to an initiative to release peregrines around the city of Kelowna in the Okanagan Valley, we collected potential peregrine prey species and analyzed whole bodies for chlorinated hydrocarbon residues. We used a simple bioaccumulation model to predict concentrations of DDE in peregrine eggs using concentrations in prey and estimates of dietary makeup as input. Peregrines would be expected to breed successfully only if they fed on a diet primarily of doves. Feeding on as little as 10% of other species such as starlings, robins, gulls and magpies would produce DDE concentrations in peregrine eggs greater than the threshold of 15 mg/kg. We also estimated the critical concentration of DDE in total prey to be about 0.5 mg/kg, one half of the previous most conservative criterion for peregrine prey. Concentrations of dieldrin and PCBs in peregrine prey are less than suggested critical levels. - Based on the level of DDE contamination of prey items, it seems unlikely that peregrine falcons could breed successfully throughout most of the Okanagan Valley of British Columbia.

  7. Kinetics of aerobic cometabolic biodegradation of chlorinated and brominated aliphatic hydrocarbons: A review.

    Science.gov (United States)

    Jesus, João; Frascari, Dario; Pozdniakova, Tatiana; Danko, Anthony S

    2016-05-15

    This review analyses kinetic studies of aerobic cometabolism (AC) of halogenated aliphatic hydrocarbons (HAHs) from 2001-2015 in order to (i) compare the different kinetic models proposed, (ii) analyse the estimated model parameters with a focus on novel HAHs and the identification of general trends, and (iii) identify further research needs. The results of this analysis show that aerobic cometabolism can degrade a wide range of HAHs, including HAHs that were not previously tested such as chlorinated propanes, highly chlorinated ethanes and brominated methanes and ethanes. The degree of chlorine mineralization was very high for the chlorinated HAHs. Bromine mineralization was not determined for studies with brominated aliphatics. The examined research period led to the identification of novel growth substrates of potentially high interest. Decreasing performance of aerobic cometabolism were found with increasing chlorination, indicating the high potential of aerobic cometabolism in the presence of medium- and low-halogenated HAHs. Further research is needed for the AC of brominated aliphatic hydrocarbons, the potential for biofilm aerobic cometabolism processes, HAH-HAH mutual inhibition and the identification of the enzymes responsible for each aerobic cometabolism process. Lastly, some indications for a possible standardization of future kinetic studies of HAH aerobic cometabolism are provided. PMID:26874310

  8. Polycyclic aromatic hydrocarbons and pesticides in soil of Vojvodina

    Directory of Open Access Journals (Sweden)

    Pucarević Mira M.

    2004-01-01

    Full Text Available The paper deals with several groups of compounds that represent the most frequent pollutants of soil in the world. The paper also reviews results of long-term studies conducted at the Institute of Field and Vegetable Crops in Novi Sad on the residues of pesticides and polycyclic aromatic hydrocarbons (PAHs in the soil of the Vojvodina Province. The analyzed samples have been found to contain residues of persistent pesticides and their metabolites lindane and its metabolites 6,20 μg/kg, alachlor 3,56 μg/kg, aldrin 2,3 μg/kg, heptachlor epoxide 0,99 μg/kg, chlordane 3,82 μg/kg, DDT and its metabolites 10,77 μg/kg, dieldrin 2,04 μg/kg, endrin 3,57 μg/kg and endrin aldehyde 1,36 μg/kg. Soil samples from Novi Sad municipality contained 53,69 μg/kg of DDT and its metabolites. The values of atrazine ranged from 0,0005 to 0,8 mg/kg. The values of PAHs were 6,64 mg/kg in industrial soil, 4,93 mg/kg in agricultural soil, and 4,55 mg/kg and 5,48 mg/kg in the Novi Sad municipality. The lowest value, 0.83 mg/kg, was found for nonagricultural/nonindustrial soils.

  9. Polycyclic aromatic hydrocarbons and pesticides in milk powder.

    Science.gov (United States)

    Dobrinas, Simona; Soceanu, Alina; Popescu, Viorica; Coatu, Valentina

    2016-05-01

    This Research Communication reports analysis of 37 compounds comprising polycyclic aromatic hydrocarbons (PAHs), organochlorine and organophosphate pesticides (OCPS and OPPS) in milk powder (one brand each of commercial infant formulae, follow-on formulae and baby formulae purchased from a local supermarket in Romania). The selected analytes were investigated using gas chromatography-mass spectrometry (GC-MS), gas chromatography with electron capture detector (GC-ECD) and gas chromatography with thermionic sensitive detection (GC-TSD). The estimated limits of detection for most target analytes were in the μg/kg level (range 0·001-0·320 µg/kg). The purpose of the study was to determine the selected analytes, to assess the exposure of babies and infants and to produce data for comparison with tolerable limits according to the European Union Regulations. In most of the samples the organochlorine pesticides values were under the limit of detection. Exceptions were heptachlor epoxide and endosulfan sulphate, the last of which was found in all analysed samples at low concentrations. We also found detectable levels of ethoprophos, parathion-methyl, chlorpyrifos, prothiofos, guthion, disulfoton and fenchlorphos in most of the analysed samples. Benzo[a]pyrene, which is used as an indicator for the presence of PAHs, was not detected in selected samples. The low level of exposure to contaminants indicates that there are no health risks for the infants and babies that consume this brand of milk powder formulae. PMID:27210498

  10. Metabolism of volatile chlorinated aliphatic hydrocarbons by Pseudomonas fluorescens.

    OpenAIRE

    Vandenbergh, P A; Kunka, B S

    1988-01-01

    A Pseudomonas fluorescens strain designated PFL12 was isolated from soil and water that were contaminated with various chloroaliphatic hydrocarbons. The isolate was able to metabolize 1,2-dichloroethane, 1,1,2-trichloroethane, 1,2-dichloropropane, 2,2-dichloropropane, and trichloroethylene.

  11. Health and environmental hazards of pesticides.

    Science.gov (United States)

    Iyaniwura, T T

    1991-01-01

    The increase in world population and in demand for food and economic crops has put a pesticide burden on man and the environment. Pesticide residues from vector control and agricultural uses contaminate the terrestrial and aquatic surroundings and contribute to the pollution problem of the environment. Various human toxicoses have resulted from pesticide use. The major pathogenic pesticides are chlorinated hydrocarbons and organophosphates. With careful and enlightened use, pesticide toxicity, to both man and the environment, could be significantly reduced.

  12. Kinetics of chlorinated hydrocarbon degradation by Methylosinus trichosporium OB3b and toxicity of trichloroethylene.

    OpenAIRE

    Oldenhuis, Roelof; Oedzes, Johannes Y.; Waarde, Jacob J. van der; Janssen, Dick B.

    1991-01-01

    The kinetics of the degradation of trichloroethylene (TCE) and seven other chlorinated aliphatic hydrocarbons by Methylosinus trichosporium OB3b were studied. All experiments were performed with cells grown under copper stress and thus expressing soluble methane monooxygenase. Compounds that were readily degraded included chloroform, trans-1,2-dichloroethylene, and TCE, with V(max) values of 550, 330, and 290 nmol min-1 mg of cells-1, respectively. 1,1-Dichloroethylene was a very poor substra...

  13. Natural attenuation of chlorinated hydrocarbons in a freshwater wetland

    Science.gov (United States)

    Lora, Michelle M.; Olsen, Lisa D.; Smith, Barrett L.

    1997-01-01

    Natural attenuation of chlorinated volatile organic compounds (VOC's) occurs as ground water discharges from a sand aquifer to a freshwater wetland at Aberdeen Proving Ground, Md. Field and laboratory results indicate that biotransformation in the anaerobic wetland sediments is an important attenuation process. Relatively high concentrations of the parent compounds trichloroethylene (TCE) and 1,1,2,2-tetrachloroethane (PCA) and low or undetectable concentrations of daughter products were measured in the aquifer. In contrast, relatively high concentrations of the daughter products cis- and trans-1,2-dichloroethylene (12DCE); vinyl chloride (VC); 1,1,2-trichloroethane (112TCA); and 1,2-dichloroethane (12DCA) were measured in ground water in the wetland sediments, although total VOC concentrations decreased upward from about 1 mu mol/L (micromoles per liter) at the base of the wetland sediments to less than 0.2 near the surface. Microcosm experiments showed that 12DCE and VC are produced from anaerobic degradation of both TCE and PCA; PCA degradation also produced 112TCA and 12DCA.

  14. Potential of non-ligninolytic fungi in bioremediation of chlorinated and polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Marco-Urrea, Ernest; García-Romera, Inmaculada; Aranda, Elisabet

    2015-12-25

    In previous decades, white-rot fungi as bioremediation agents have been the subjects of scientific research due to the potential use of their unspecific oxidative enzymes. However, some non-white-rot fungi, mainly belonging to the Ascomycota and Zygomycota phylum, have demonstrated their potential in the enzymatic transformation of environmental pollutants, thus overcoming some of the limitations observed in white-rot fungi with respect to growth in neutral pH, resistance to adverse conditions and the capacity to surpass autochthonous microorganisms. Despite their presence in so many soil and water environments, little information exists on the enzymatic mechanisms and degradation pathways involved in the transformation of hydrocarbons by these fungi. This review describes the bioremediation potential of non-ligninolytic fungi with respect to chlorinated hydrocarbons and polycyclic aromatic hydrocarbons (PAHs) and also shows known conversion pathways and the prospects for future research.

  15. Transformation of Organophosphorus Pesticides in the Presence of Aqueous Chlorine: Kinetics, Pathways, and Structure-Activity Relationships

    Science.gov (United States)

    The fate of organophosphorus (OP) pesticides in the presence of aqueous chlorine was investigated under simulated drinking water treatment conditions. Intrinsic rate coefficients were found for the reaction of hypochlorous acid (kHOCl,OP) and hypochlorite ion (kOCl,OP) for eight...

  16. Predictors of PCP, OH-PCBs, PCBs and chlorinated pesticides in a general female Norwegian population.

    Science.gov (United States)

    Rylander, Charlotta; Lund, Eiliv; Frøyland, Livar; Sandanger, Torkjel M

    2012-08-01

    The aims of the current study were to assess plasma concentrations and predictors of halogenated phenolic compounds (HPCs), polychlorinated biphenyls (PCBs) and chlorinated pesticides in a representative group of postmenopausal Norwegian women (n=311, mean age: 56 years). In addition to delivering a blood sample, the participants had also filled out a detailed questionnaire regarding their current health status, use of medication and dietary habits, etc. The association between a large number of dietary variables, lifestyle factors and plasma concentration of organic pollutants were investigated using multivariate statistics. Within the current study group, p,p'-DDE (median: 903 ng/L w.w.) and pentachlorophenol (PCP, median: 711 ng/L w.w.) were the dominating compounds on a wet weight basis and were present in considerable higher concentrations than the PCBs, the hydroxylated PCBs (OH-PCBs) and the remaining chlorinated pesticides. Of the PCBs, PCB 153 was detected in highest concentrations, whereas 4-OH-PCB187 was present in highest concentration of the selected OH-PCBs. The ratio of ΣOH-PCB to ΣPCB varied between 0.06 and 0.77 ng/L and were significantly lower in individuals with higher ΣPCB concentration. PCP did not co-vary with the other contaminants, indicating a different route of exposure. No clear food cluster was positively associated with PCP exposure; however intake of marine food was negatively linked to PCP concentration and age and being a non-smoker were positive predictors of PCP. The other investigated contaminants co-varied and were positively associated with age, plasma concentrations of marine derived omega-3 fatty acids and a traditional Norwegian fish and bread based diet. The difference in contaminant concentration between high, medium and low consumers of total marine food were however marginal for the dominating PCBs and chlorinated pesticides. The current results indicate however that marine food in itself could be a source of some of

  17. Predictors of PCP, OH-PCBs, PCBs and chlorinated pesticides in a general female Norwegian population.

    Science.gov (United States)

    Rylander, Charlotta; Lund, Eiliv; Frøyland, Livar; Sandanger, Torkjel M

    2012-08-01

    The aims of the current study were to assess plasma concentrations and predictors of halogenated phenolic compounds (HPCs), polychlorinated biphenyls (PCBs) and chlorinated pesticides in a representative group of postmenopausal Norwegian women (n=311, mean age: 56 years). In addition to delivering a blood sample, the participants had also filled out a detailed questionnaire regarding their current health status, use of medication and dietary habits, etc. The association between a large number of dietary variables, lifestyle factors and plasma concentration of organic pollutants were investigated using multivariate statistics. Within the current study group, p,p'-DDE (median: 903 ng/L w.w.) and pentachlorophenol (PCP, median: 711 ng/L w.w.) were the dominating compounds on a wet weight basis and were present in considerable higher concentrations than the PCBs, the hydroxylated PCBs (OH-PCBs) and the remaining chlorinated pesticides. Of the PCBs, PCB 153 was detected in highest concentrations, whereas 4-OH-PCB187 was present in highest concentration of the selected OH-PCBs. The ratio of ΣOH-PCB to ΣPCB varied between 0.06 and 0.77 ng/L and were significantly lower in individuals with higher ΣPCB concentration. PCP did not co-vary with the other contaminants, indicating a different route of exposure. No clear food cluster was positively associated with PCP exposure; however intake of marine food was negatively linked to PCP concentration and age and being a non-smoker were positive predictors of PCP. The other investigated contaminants co-varied and were positively associated with age, plasma concentrations of marine derived omega-3 fatty acids and a traditional Norwegian fish and bread based diet. The difference in contaminant concentration between high, medium and low consumers of total marine food were however marginal for the dominating PCBs and chlorinated pesticides. The current results indicate however that marine food in itself could be a source of some of

  18. Aerobic Biodegradation of Chlorinated Hydrocarbons by Bacillus circulans WZ-12 CCTCC M 207006 under Saline Conditions

    Institute of Scientific and Technical Information of China (English)

    YU Jianming; CAI Wenji; ZHAO Shiliang; WANG Yan; CHEN Jianmeng

    2013-01-01

    A novel saline-tolerant bacterium Bacillus circulans WZ-12 was evaluated for its potential to degrade four chlorinated hydrocarbons under saline conditions.CH2Cl2 was effectively degraded by Bacillus circulans WZ-12 cells in the medium containing NaC1 concentrations ranging from 5 g·L-1 to 10 g·L-1,and the maximum degradation efficiency (85%) was achieved at NaCl concentration of 10 g·L-.Similarly,Bacillus circulans WZ-12was able to degrade CH2BtCl,C2H4Cl2,and C2H2Cl2 in the presence of 10 g NaCl per liter within 24 h.Cells of Bacillus circulans WZ-12 grown in minimal salt medium contained low levels of glycine betaine (GB),but GB levels were 3-to 5-fold higher in cells grown in media with high salt.Kinetic analysis revealed that biodegradation of the four chlorinated hydrocarbons was concentration dependent and a linear inverse correlation (R2=0.85-0.94)was observed between the rate of biodegradation (Ⅴ) and salt concentration from 5 g·L-1 to 60 g·L-1.The growing cells (in minimal salt medium) degraded approximately 50% of the CH2Cl2 within 24 h,whereas the resting cells (in physiological saline) degraded only 25% of the CH2Cl2 within 24 h and were inactive after 36 h cultivation.Biodegradation could be repeatedly performed for more than 192 h with more than 50% removal efficiency.Bacillus circulans WZ-12 grows well in an aqueous/oil system,hence,it is effective for the treatment of industrial effluents that contain chlorinated hydrocarbons with high salt concentrations.

  19. Sorption- and diffusion-associated isotope effects for chlorinated and non chlorinated aromatic hydrocarbons in a sediment pore water diffusion sampler

    Science.gov (United States)

    Passeport, E.; Chu, K.; Lacrampe Couloume, G.; Landis, R.; Lutz, E. J.; Mack, E. E.; West, K.; Sherwood Lollar, B.

    2013-12-01

    Compound Specific Isotope Analysis (CSIA) has gained prominence for evaluation of microbial and abiotic degradation processes governing the fate of organic contaminants in groundwater. At the sediment pore water interface, in wetland or river bottom sediments, variations in oxidation-reduction conditions can affect reaction mechanisms and hence the contaminant mass flux discharged to surface waters. Carbon isotope fractionation has been shown to be an important tool in identifying the effects of degradation and differentiating between different degradation pathways. To date, while passive diffusion samplers (commonly called 'peepers') have provided a powerful tool for high spatial resolution sampling for dissolved VOC across the sediment water interface, peepers' compatibility with CSIA has never been evaluated. The operating principle of peepers involves compound diffusion from the sediment pore water to the peeper chambers via a membrane. In this study, we evaluated the isotope effects of diffusion through, and possible adsorption to a polysulfone membrane for priority groundwater contaminants including chlorinated and non-chlorinated aromatic hydrocarbons. Chlorinated benzenes tend to accumulate in the food web and therefore represent a significant threat to water resources. This is due to their larger sorption coefficients (Koc) and higher hydrophobicity properties (logKow) compared to other commonly-studied compounds (e.g., chlorinated ethenes). Application of CSIA to BTEX and chlorinated ethenes has demonstrated that non-degradative processes (e.g., sorption, volatilization, diffusion) typically result in smaller carbon isotope fractionation compared to degradative processes that involve breaking bonds. The large sorption properties of chlorinated benzenes preclude a direct extrapolation to these compounds of existing data on sorption-associated isotope effects obtained on other compounds. To date, similar studies have not been done for chlorinated aromatics

  20. Effect of reduced iron on the degradation of chlorinated hydrocarbons in contaminated soil and ground water: A review of publications

    Science.gov (United States)

    Vodyanitskii, Yu. N.

    2014-02-01

    Chlorinated hydrocarbons are among the most hazardous organic pollutants. The traditional remediation technologies, i.e., pumping of contaminated soil- and groundwater and its purification appear to be costly and not very efficient as applied to these pollutants. In the last years, a cheaper method of destroying chlorine-replaced hydrocarbons has been used based on the construction of an artificial permeable barrier, where the process develops with the participation of in situ bacteria activated by zerovalent iron. The forced significant decrease in the redox potential (Eh) down to -750 mV provides the concentration of electrons necessary for the reduction of chlorinated hydrocarbons. A rise in the pH drastically accelerates the dechlorination process. In addition to chlorine-organic compounds, ground water is often contaminated with heavy metals. The influence of the latter on the effect of zerovalent iron may be different: both accelerating its degradation (Cu) and inhibiting it (Cr). Most of the products of zerovalent iron corrosion, i.e., green rust, magnetite, ferrihydrite, hematite, and goethite, weaken the efficiency of the Fe0 barrier by mitigating the dechlorination and complicating the water filtration. However, pyrrhotite FeS, on the contrary, accelerates the dechlorination of chlorine hydrocarbons.

  1. Impact of some chlorinated pesticides on the haematology of the fish Cyprinuscarpio and Puntius ticto

    Institute of Scientific and Technical Information of China (English)

    Shanta Satyanarayan; Rajesh S. Bejankiwar; P.R. Chaudhari; J . P. Kotangale; Ahana Satyanarayan

    2004-01-01

    The effects of pesticides on blood characteristics and histological changes in erythrocytes of the fish species Cyprinus carpio and Puntius ticto were studied. The fishes were exposed to sub lethal concentrations of different chlorinated pesticides namely aldrin, dieldrin, DDT, BHC and chlordane for 10, 20 and 30 d in continuous flow-through test. The LC50 values were calculated based on acute toxicity tests and the sublethal doses were arrived at for chronic bioassay studies. Results showed an increase in haemoglobin content of both Cyprinus carpio and Puntius ticto in case of aldrin and dieldrin. Haemoglobin content reduced from an initial 13 g/100 ml to 8.07 and 10.15 g/100 ml in case of Cyprinus at the end of ten days exposure to aldrin and dieldrin respectively, and gradually increased to 8.7 g/100 ml and 10.15 g/100 ml after 20 d of exposure. The haemoglobin content after 30 d exposure to aldrin and dieldrin was 10.15 g/100 ml and 11.6 g/100 ml respectively. In case of Puntius ticto, the haemoglobin content in control fishes recorded was 12.8 g/100 ml while in case of fish exposed to aldrin, the haemoglobin content reduced initially on ten days exposure to 10.15 g/100 ml and increased to 11.6 g/100 ml and 13.0 g/100 ml during twenty days and thirty days exposure respectively. This trend was also observed with dieldrin in both the fishes studied. Red blood cells were also counted in case of all the pesticides and exposure periods with respect to Cyprinus carpio and Puntius ticto. Irrespective of the species and pesticide, the RBC counts uniformly showed decreasing trend with the increase in exposure period, while packed cell volume, PCV(%) showed increasing trend with respect to increase in exposure period in case of aldrin and dieldrin in both the fishes. But DDT, BHC and chlordane showed decreasing trend in PCV(%) values with increasing periods of exposure.

  2. Chromatographic study of gamma-ray irradiated degradation of chlorinated hydrocarbon in water

    International Nuclear Information System (INIS)

    Degradation of chlorinated hydrocarbon in gamma ray irradiation was examined in order to get information on treatment of groundwater. Water chloroform was sealed into a vial irradiated with gamma ray. Both gas chromatography and ion chromatography were applied for determination of degradation products. Carbon dioxide, carbon monoxide, methane, ethane and chloride ion were detected in the irradiated system. Effect of radiation dose on the gamma ray induced chloroform degradation was investigated. The elimination of chloride ion and the degradation of chloroform were promoted by gamma irradiation in a dose-dependent manner. The G(CHCl3), which was defined as the number of degraded chloroform molecules when absorbed 100eV, was inferred to be 3.1. The degradation mechanism of chloroform irradiated with gamma ray seemed to involve that chloroform reacted with electron from radiolysis of water and the elimination of chloride ion occurred. (author)

  3. Rush-hour aromatic and chlorinated hydrocarbons in selected subway stations of Shanghai, China

    Institute of Scientific and Technical Information of China (English)

    Yanli Zhang; Chunlei Li; Xinming Wang; Hai Guo; Yanli Feng; Jianmin Chen

    2012-01-01

    Air samples were collected simultaneously at platform,mezzanine and outdoor in five typical stations of subway system in Shanghai,China using stainless steel canisters and analyzed by gas chromatography-mass selective detector (GC-MSD) after cryogenic preconcentration.Benzene,toluene,ethylbenzene and xylenes (BTEX) at the platforms and mezzanines inside the stations averaged (10.3± 2.1),(38.7 ± 9.0),(19.4 ± 10.1) and (30.0 ± 11.1) μg/m3,respectively; while trichloroethylene (TrCE),tetrachloroethylene (TeCE)and para-dichlorobenzene (pDCB),vinyl chloride and carbon tetrachloride were the most abundant chlorinated hydrocarbons inside the stations with average levels of (3.6 ± 1.3),(1.3 ± 0.5),(4.1 ± 1.1),(2.2 ± 1.1) and (1.2 ± 0.3) μg/m3,respectively.Mean levels of major aromatic and chlorinated hydrocarbons were higher indoor (platforms and mezzanines) than outdoor with average indoor/outdoor (I/O)ratios of 1.1-9.5,whereas no significant indoor/outdoor differences were found except for benzene and TrCE.The highly significant mutual correlations (p < 0.01) for BTEX between indoor and outdoor and their significant correlation (p < 0.05) with methyl tert-butyl ether (MTBE),a marker of traffic-related emission without other indoor and outdoor sources,indicated that BTEX were introduced into the subway stations from indoor/outdoor air exchange and traffic emission should be their dominant source.TrCE and pDCB were mainly from indoor emission and TeCE might have both indoor emission sources and contribution from outdoor air,especially in the mezzanines.

  4. Rush-hour aromatic and chlorinated hydrocarbons in selected subway stations of Shanghai, China.

    Science.gov (United States)

    Zhang, Yanli; Li, Chunlei; Wang, Xinming; Guo, Hai; Feng, Yanli; Chen, Jianmin

    2012-01-01

    Air samples were collected simultaneously at platform, mezzanine and outdoor in five typical stations of subway system in Shanghai, China using stainless steel canisters and analyzed by gas chromatography-mass selective detector (GC-MSD) after cryogenic preconcentration. Benzene, toluene, ethylbenzene and xylenes (BTEX) at the platforms and mezzanines inside the stations averaged (10.3 +/- 2.1), (38.7 +/- 9.0), (19.4 +/- 10.1) and (30.0 +/- 11.1) microg/m3, respectively; while trichloroethylene (TrCE), tetrachloroethylene (TeCE) and para-dichlorobenzene (pDCB), vinyl chloride and carbon tetrachloride were the most abundant chlorinated hydrocarbons inside the stations with average levels of (3.6 +/- 1.3), (1.3 +/- 0.5), (4.1 +/- 1.1), (2.2 +/- 1.1) and (1.2 +/- 0.3) microg/m3, respectively. Mean levels of major aromatic and chlorinated hydrocarbons were higher indoor (platforms and mezzanines) than outdoor with average indoor/outdoor (I/O) ratios of 1.1-9.5, whereas no significant indoor/outdoor differences were found except for benzene and TrCE. The highly significant mutual correlations (p tert-butyl ether (MTBE), a marker of traffic-related emission without other indoor and outdoor sources, indicated that BTEX were introduced into the subway stations from indoor/outdoor air exchange and traffic emission should be their dominant source. TrCE and pDCB were mainly from indoor emission and TeCE might have both indoor emission sources and contribution from outdoor air, especially in the mezzanines. PMID:22783624

  5. Anaerobic biotransformation of chlorinated aliphatic hydrocarbons: Ugly duckling to beautiful swan

    Energy Technology Data Exchange (ETDEWEB)

    Parkin, G.F.

    1999-10-01

    For many years anaerobic biological processes were reputed to be more sensitive than aerobic processes to toxic substances such as chlorinated aliphatic hydrocarbons (CAH) and thus a poor choice for treating water containing these compounds. This was especially true for water containing perchloroethylene (PCE) or trichloroethylene (TCE) because vinyl chloride, a human carcinogen, is produced when these two compounds are degraded anaerobically. Aerobic treatment with organisms containing oxygenase enzyme systems, which could fortuitously degrade a wide variety of chlorinated aliphatics (but not PCE), was favored. Recently, however, several enrichments and organisms have been isolated that will convert PCE and TCE into ethene and ethane, as shown by field data. Because of this evidence, anaerobic processes are now considered a significant alternative treatment for CAH contamination. Recent work at the University of Iowa, Iowa City, has focused on the effect of mixtures of CAHs on biotransformation of individual organic compounds and the potential for a combined methanogen-iron (Fe(0)) system to improve CAH bioremediation. At the concentration ranges tested, the presence of a mixture of CAHs seems to decrease rate of transformation of individual organics. However, there are important exceptions; in some cases a mixture of CAHs seems to facilitate transformation of an individual organic compound. Combination of an active methanogenic population with Fe(0) increases the rate and extent of transformation of carbon tetrachloride and chloroform. Results with PCE and 1,1,1-trichloroethane are less clear.

  6. Volatile Short-chain Chlorinated Hydrocarbons in the Groundwater of the City of Zagreb

    Directory of Open Access Journals (Sweden)

    Marijanović-Rajčić, M.

    2008-01-01

    Full Text Available The aim of the study was to assess the quality of the groundwater sampled from private wells and the public water-supply system in terms of estimating the contamination caused by short-chain chlorinated hydrocarbons, as well as to estimate the exposure of the citizens dwelling in different suburbs to these pollutants of their drinking water (Fig. 1. The aim of the study was also to determine which suburb is supplied through the public water-supply system with water originating from the Sašnak spring that is contaminated with volatile chlorinated short-chain hydrocarbons.Drinking water samples were taken from 3 private wells and 1 public water-supply system situated in 3 Zagreb suburbs - Pešćenica, Trnje, and Trešnjevka. The sampling was carried out during 2003 and was undertaken on a seasonal basis. Short-chain chlorinated hydrocarbons - 1,1,1-trichloroethane, carbon tetrachloride, 1,1,2-trichloroethene and 1,1,2,2-tetrachloroethene - were determined by gas chromatography, following "liquid-liquid extraction" in pentane. For that purpose, we applied the gas chromatograph equipped with an electron-capture detector, thermo-programmable operations, and a suitable capillary column. The technique applied was that of split-injection.The groundwater of the City of Zagreb was found to be contaminated with volatile chlorinated hydrocarbons. The concentration level of 1,1,1-trichloroethane, determined in most of the samples, was found to be low (Fig. 2. On the other hand, 1,1,2-trichloroethene was present in all samples in concentrations of about 1 µg l-1- (Fig. 3. Only the drinking water samples taken from private wells in the suburb of Trnje contained somewhat higher mass concentrations of 1,1,1-trichloroethane, with the peak value of 19.03 µg l-1, measured in the winter season. In the samples taken from private wells in Trnje, the mass concentrations of 1,1,2,2-tetrachloroethene rangedfrom 15.30 µg l-1 to 18.65 µg l-1, as measured in autumn

  7. Reproductive success and chlorinated hydrocarbon contamination of resident great blue herons (Ardea herodias) from coastal British Columbia, Canada, 1977 to 2000

    International Nuclear Information System (INIS)

    Human disturbance and loss of nesting habitat were more important factors than chlorinated hydrocarbons in changing heron reproductive success. - Over the period 1977-2000, eggs of Pacific great blue heron (Ardea herodias fannini) were collected from 23 colonies along the southern coast of British Columbia, Canada, and analyzed for persistent organochlorine (OC) pesticides and polychlorinated biphenyls (PCBs). Concentrations of OC pesticides in eggs declined sharply in the late 1970s, after which there were minimal changes. The sums of PCB congeners were not reduced appreciably during the 1980s and 1990s, but Aroclor 1260 concentrations suggested a sharp decline in PCB contamination of eggs in the late 1970s, similar to that shown for OC pesticides. Eggs collected along or near the Fraser River delta showed higher levels of most pesticides compared to other monitored colonies. Although the delta lands support a long-standing agricultural economy, the primary factors influencing OC levels in the delta colonies were thought to be driven by estuarine processes. We suggest two possible influencing factors were: 1) a greater rate of bioaccumulation in the estuary due to the deposition of particulates collected over a vast area encompassed by the Fraser River watershed; or 2) a higher rate of biomagnification in the estuary due to species differences at lower trophic levels of the heron food chain. Eggs from urban colonies contained higher levels of PCBs. The congener pattern was not clearly different from that observed in less contaminated eggs from rural and pulp mill-influenced colonies, except that colonies in Vancouver had greater proportions of PCB-66, suggesting a local source of Aroclor 1242. Productivity in the coastal heron colonies was highly variable over the period of study, with 71% of recorded colony-wide reproductive failures occurring in colonies near pulp mills. However, the predominant factors influencing reproductive success were probably disturbance

  8. Chlorine

    Energy Technology Data Exchange (ETDEWEB)

    Talmage, Sylvia Smith [ORNL

    2009-01-01

    Following a brief description of the use of chlorine as a chemical warfare agent in World War I, this chapter summarizes physical and chemical data and recent clinical and controlled laboratory studies on the irritant and lethal effects of chlorine. The mechanism of toxicity for both irritation and lethal effects is described. The mathematical relationship between concentration and exposure duration for a set endpoint is given for both an irritancy response and mortality. This information can be used to assist in time-scaling for the set endpoint to other exposure durations. Risk assessment addresses the potential for greater effects in sensitive populations such as asthmatics. A concentration of 0.5 ppm for up to 8 hours is a no-adverse-effect concentration in most sensitive subjects; whereas, a concentration of 1.0 ppm induces some sensory irritation and transient changes in respiratory tract airflow parameters. Treatment and intervention of exposed individuals is dependent upon symptoms

  9. Reproductive and morphological condition of wild mink (Mustela vison) and river otters (Lutra canadensis) in relation to chlorinated hydrocarbon contamination.

    OpenAIRE

    Harding, L E; Harris, M L; Stephen, C. R.; Elliott, J.E.

    1999-01-01

    We assessed chlorinated hydrocarbon contamination of mink and river otters on the Columbia and Fraser River systems of northwestern North America, in relation to morphological measures of condition. We obtained carcasses of mink and river otters from commercial trappers during the winters 1994-1995 and 1995-1996. Necropsies included evaluation of the following biological parameters: sex, body mass and length, age, thymus, heart, liver, lung, spleen, pancreas, kidney, gonad, omentum, adrenal g...

  10. Microbial diversity in a hydrocarbon- and chlorinated-solvent- contaminated aquifer undergoing intrinsic bioremediation

    Science.gov (United States)

    Dojka, M.A.; Hugenholtz, P.; Haack, S.K.; Pace, N.R.

    1998-01-01

    A culture-independent molecular phylogenetic approach was used to survey constituents of microbial communities associated with an aquifer contaminated with hydrocarbons (mainly jet fuel) and chlorinated solvents undergoing intrinsic bioremediation. Samples were obtained from three redox zones: methanogenic, methanogenic-sulfate reducing, and iron or sulfate reducing. Small-subunit rRNA genes were amplified directly from aquifer material DNA by PCR with universally conserved or Bacteria- or Archaea-specific primers and were cloned. A total of 812 clones were screened by restriction fragment length polymorphisms (RFLP), approximately 50% of which were unique. All RFLP types that occurred more than once in the libraries, as well as many of the unique types, were sequenced. A total of 104 (94 bacterial and 10 archaeal) sequence types were determined. Of the 94 bacterial sequence types, 10 have no phylogenetic association with known taxonomic divisions and are phylogenetically grouped in six novel division level groups (candidate divisions WS1 to WS6); 21 belong to four recently described candidate divisions with no cultivated representatives (OPS, OP8, OP10, and OP11); and 63 are phylogenetically associated with 10 well-recognized divisions. The physiology of two particularly abundant sequence types obtained from the methanogenic zone could be inferred from their phylogenetic association with groups of microorganisms with a consistent phenotype. One of these sequence types is associated with the genus Syntrophus; Syntrophus spp. produce energy from the anaerobic oxidation of organic acids, with the production of acetate and hydrogen. The organism represented by the other sequence type is closely related to Methanosaeta spp., which are known to be capable of energy generation only through aceticlastic methanogenesis. We hypothesize, therefore, that the terminal step of hydrocarbon degradation in the methanogenic zone of the aquifer is aceticlastic methanogenesis and

  11. Chlorinated Hydrocarbon Degradation in Plants: Mechanisms and Enhancement of Phytoremediation of Groundwater Contamination

    Energy Technology Data Exchange (ETDEWEB)

    Stuart Strand

    2004-09-27

    The research objectives for this report are: (1) Transform poplar and other tree species to extend and optimize chlorinated hydrocarbon (CHC) oxidative activities. (2) Determine the mechanisms of CHC oxidation in plants. (3) Isolate the genes responsible for CHC oxidation in plants. We have made significant progress toward an understanding of the biochemical mechanism of CHC transformation native to wild-type poplar. We have identified chloral, trichloroethanol, trichloroacetic acid, and dichloroacetic acid as products of TCE metabolism in poplar plants and in tissue cultures of poplar cells.(Newman et al. 1997; Newman et al. 1999) Use of radioactively labeled TCE showed that once taken up and transformed, most of the TCE was incorporated into plant tissue as a non-volatile, unextractable residue.(Shang et al. 2001; Shang and Gordon 2002) An assay for this transformation was developed and validated using TCE transformation by poplar suspension cells. Using this assay, it was shown that two different activities contribute to the fixation of TCE by poplar cells: one associated with cell walls and insoluble residues, the other associated with a high molecular weight, heat labile fraction of the cell extract, a fixation that was apparently catalyzed by plant enzymes.

  12. Use of chlorination, ozonization and GAC adsorption to eliminate triazine pesticides in water supplies; Eliminacion de plaguicidas en aguas de abastecimiento mediante cloracion, ozonizacion y adsorcion con GAC

    Energy Technology Data Exchange (ETDEWEB)

    Ormad Melero, M. P.; Garcia Castillo, F. J.; Munarriz Cid, B.

    2009-07-01

    This study is focused on the research made between Facsa and Universidad de Zaragoza (Spain) related to the oxidation techniques application by chlorination and ozonization, and their combination with granular activated carbon (GAC) adsorption of mineral origin, in order to control triazine pesticides in water supplies. Experiments are carried out is a pilot plant. Although the chlorination or ozonization can partially degrade pesticides under study (atrazine, simazine, terbutilazine and bromacil), their passing through an adsorption column with GAC mineral, achieves their total removal when their initial concentrations are about 500 ng/l. These concentrations are obtained by fortification of studied sample. (Author) 9 refs.

  13. Occurrence and distribution of PAHs, PCBs, and chlorinated pesticides in Tunisian soil irrigated with treated wastewater.

    Science.gov (United States)

    Haddaoui, Imen; Mahjoub, Olfa; Mahjoub, Borhane; Boujelben, Abdelhamid; Di Bella, Giuseppa

    2016-03-01

    Treated wastewater (TWW) is a well recognized source of organic pollutants (OPs) that may accumulate during irrigation. For the first time, data on the occurrence of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyles (PCBs) and organochlorinated pesticides (OCPs) in wastewater irrigated soil in Nabeul (Tunisia) are reported. 13 PAHs, 18 PCBs and 16 OCPs were analyzed in soil samples collected at 0-10 and 10-20 cm depth before each and every irrigation and after the irrigation period expanding from June to October. Soil was extracted with an accelerated solvent extractor and analyzed by a tandem gas chromatograph in selected reaction monitoring mode (GC/MS/MS/SRM). OPs residues were detected before irrigation and accumulated at the end of the season for some of them. The total concentration of PAHs varied between 120.01 and 365.18 μg kg(-1) dry weight (dw) at 0-10 cm depth before and at the end of irrigation, respectively. The total concentration of PCBs varied between 11.26 and 21.89 μg kg(-1) dw at 0-10 cm, being higher than those reported for 10-20 cm. The six indicator PCB congeners (28, 52, 101, 138, 153, 180) were predominant. OCPs concentrations ranged between 12.49 and 21.81 μg kg(-1) at 0-10 cm and between 74.03 and 310.54 μg kg(-1) at 10-20 cm depth. DDT was predominant accounting for more than 94% of the total OCPs. In view of the present results, OPs are relevant to the agricultural environment, calling for more research on their persistence and potential transfer to plants and/or groundwater while taking into account farmers' practices.

  14. Occurrence and distribution of PAHs, PCBs, and chlorinated pesticides in Tunisian soil irrigated with treated wastewater.

    Science.gov (United States)

    Haddaoui, Imen; Mahjoub, Olfa; Mahjoub, Borhane; Boujelben, Abdelhamid; Di Bella, Giuseppa

    2016-03-01

    Treated wastewater (TWW) is a well recognized source of organic pollutants (OPs) that may accumulate during irrigation. For the first time, data on the occurrence of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyles (PCBs) and organochlorinated pesticides (OCPs) in wastewater irrigated soil in Nabeul (Tunisia) are reported. 13 PAHs, 18 PCBs and 16 OCPs were analyzed in soil samples collected at 0-10 and 10-20 cm depth before each and every irrigation and after the irrigation period expanding from June to October. Soil was extracted with an accelerated solvent extractor and analyzed by a tandem gas chromatograph in selected reaction monitoring mode (GC/MS/MS/SRM). OPs residues were detected before irrigation and accumulated at the end of the season for some of them. The total concentration of PAHs varied between 120.01 and 365.18 μg kg(-1) dry weight (dw) at 0-10 cm depth before and at the end of irrigation, respectively. The total concentration of PCBs varied between 11.26 and 21.89 μg kg(-1) dw at 0-10 cm, being higher than those reported for 10-20 cm. The six indicator PCB congeners (28, 52, 101, 138, 153, 180) were predominant. OCPs concentrations ranged between 12.49 and 21.81 μg kg(-1) at 0-10 cm and between 74.03 and 310.54 μg kg(-1) at 10-20 cm depth. DDT was predominant accounting for more than 94% of the total OCPs. In view of the present results, OPs are relevant to the agricultural environment, calling for more research on their persistence and potential transfer to plants and/or groundwater while taking into account farmers' practices. PMID:26716883

  15. Quantification of Degradation of Chlorinated Hydrocarbons in Saturated Low Permeability Sediments Using Compound-Specific Isotope Analysis.

    Science.gov (United States)

    Wanner, Philipp; Parker, Beth L; Chapman, Steven W; Aravena, Ramon; Hunkeler, Daniel

    2016-06-01

    This field and modeling study aims to reveal if degradation of chlorinated hydrocarbons in low permeability sediments can be quantified using compound-specific isotope analysis (CSIA). For that purpose, the well-characterized Borden research site was selected, where an aquifer-aquitard system was artificially contaminated by a three component chlorinated solvent mixture (tetrachloroethene (PCE) 45 vol %, trichloroethene (TCE) 45 vol %, and chloroform (TCM) 10 vol %). Nearly 15 years after the contaminant release, several high-resolution concentration and CSIA profiles were determined for the chlorinated hydrocarbons that had diffused into the clayey aquitard. The CSIA profiles showed large shifts of carbon isotope ratios with depth (up to 24‰) suggesting that degradation occurs in the aquitard despite the small pore sizes. Simulated scenarios without or with uniform degradation failed to reproduce the isotope data, while a scenario with decreasing degradation with depth fit the data well. This suggests that nutrients had diffused into the aquitard favoring stronger degradation close to the aquifer-aquitard interface than with increasing depth. Moreover, the different simulation scenarios showed that CSIA profiles are more sensitive to different degradation conditions compared to concentration profiles highlighting the power of CSIA to constrain degradation activities in aquitards. PMID:27153381

  16. Degradation kinetics of chlorinated aliphatic hydrocarbons by methane oxidizers naturally-associated with wetland plant roots.

    Science.gov (United States)

    Powell, C L; Goltz, M N; Agrawal, A

    2014-12-01

    Chlorinated aliphatic hydrocarbons (CAHs) are common groundwater contaminants that can be removed from the environment by natural attenuation processes. CAH biodegradation can occur in wetland environments by reductive dechlorination as well as oxidation pathways. In particular, CAH oxidation may occur in vegetated wetlands, by microorganisms that are naturally associated with the roots of wetland plants. The main objective of this study was to evaluate the cometabolic degradation kinetics of the CAHs, cis-1,2-dichloroethene (cisDCE), trichloroethene (TCE), and 1,1,1-trichloroethane (1,1,1TCA), by methane-oxidizing bacteria associated with the roots of a typical wetland plant in soil-free system. Laboratory microcosms with washed live roots investigated aerobic, cometabolic degradation of CAHs by the root-associated methane-oxidizing bacteria at initial aqueous [CH4] ~1.9mgL(-1), and initial aqueous [CAH] ~150μgL(-1); cisDCE and TCE (in the presence of 1,1,1TCA) degraded significantly, with a removal efficiency of approximately 90% and 46%, respectively. 1,1,1TCA degradation was not observed in the presence of active methane oxidizers. The pseudo first-order degradation rate-constants of TCE and cisDCE were 0.12±0.01 and 0.59±0.07d(-1), respectively, which are comparable to published values. However, their biomass-normalized degradation rate constants obtained in this study were significantly smaller than pure-culture studies, yet they were comparable to values reported for biofilm systems. The study suggests that CAH removal in wetland plant roots may be comparable to processes within biofilms. This has led us to speculate that the active biomass may be on the root surface as a biofilm. The cisDCE and TCE mass losses due to methane oxidizers in this study offer insight into the role of shallow, vegetated wetlands as an environmental sink for such xenobiotic compounds.

  17. Chlorinated hydrocarbons in livers of American mink (Mustela vison) and river otter (Lutra canadensis) from the Columbia and Fraser River Basins, 1990-1992

    Science.gov (United States)

    Elliott, J.E.; Henny, Charles J.; Harris, M.L.; Wilson, L.K.; Norstrom, R.J.

    1999-01-01

    We investigated chlorinated hydrocarbon contaminants in aquatic mustelid species on the Fraser and Columbia Rivers of northwestern North America. Carcasses of river otter (Lutra canadensis) (N=24) and mink (Mustela vison) (N=34) were obtained from commercial trappers during the winters of 1990-91 and 1991a??92. Pooled liver samples were analyzed for organochlorine pesticides, polychlorinated biphenyls (PCBs), including non-ortho congeners, polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs). Most samples contained detectable concentrations of DDE, PCBs, although there was substantial variability in patterns and trends among neighboring samples. Concentrations of DDE were in some mink and several otter samples from the lower Columbia River elevated (to 4700 g/kg wet weight); excluding one mink sample from the Wenatchee area, mean DDE levels generally decreased between 1978a??79 and 1990a??92. PCBs were present in all samples. PCB concentrations in otter livers collected from the lower Columbia were ten-fold lower than measured a decade previously; nevertheless, a sample taken near Portland had a mean concentration of 1500 g/kg, within a range of concentrations associated with reproductive effects in captive mink. Concentrations of 2,3,7,8-TCDD and TCDF were generally below detection limits, except for one otter collected near a pulp mill at Castlegar, on the upper Columbia, with 11 ng TCDD/kg in liver. Elevated concentrations of higher chlorinated PCDD/Fs, probably resulting from use of chlorophenolic wood preservatives, were found in both species; one otter sample from the lower Columbia had 2200 ng OCDD/kg. International TCDD toxic equivalent levels in mink (31 ng/kg) and otter (93 ng/kg) from the lower Columbia River approached toxicity thresholds for effects on reproduction in ranch mink.

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

    Science.gov (United States)

    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...

  19. Pesticide residues in the soil of the Central Jordan Valley

    International Nuclear Information System (INIS)

    Soil samples were taken from three zones in the Central Jordan Valley to evaluate the range of contamination with pesticides. Several pesticides belonging to different groups, particularly chlorinated hydrocarbon insecticides such as the DDT family and cyclodienes, were detected. In zone I, most of the chlorinated hydrocarbon insecticides occurred in open fields cultivated with tomatoes at a depth of 30-60 cm, at 0-15 and 15-30 cm in zone II, and at 0-15 and 30-60 cm in zone III. When considering pesticide residues under plastic house conditions cultivated with tomatoes, most of the chlorinated hydrocarbon insecticide residues were detected at a depth of 0-15 and 15-30 cm in zone I, at 0-15, 15-30 and 30-60 cm in zone II, and at 0-15 and 15-30 cm in zone III of the Central Jordan Valley. (author). 13 refs, 3 tabs

  20. Synergistic degradation of chlorinated hydrocarbons with microorganisms and zero valent iron

    Science.gov (United States)

    Schöftner, Philipp; Summer, Dorothea; Leitner, Simon; Watzinger, Andrea; Wimmer, Bernhard; Reichenauer, Thomas

    2016-04-01

    Sites contaminated with chlorinated hydrocarbons (CHC) are located mainly within build-up regions. Therefore in most cases only in-situ technologies without excavation of soil material can be used for remediation. This project examines a novel in-situ remediation method, in which the biotic degradation via bacteria is combined with abiotic degradation via zero-valent iron particles (ZVI). ZVI particles are injected into the aquifer where CHC-molecules are reductively dechlorinated. However Fe0 is also oxidized by reaction with water leading to generation of H2 without any CHC degradation. To achieve biotic degradation often strictly anaerobic strains of the bacteria Dehalococcoides are used. These bacteria can dechlorinate CHC by utilizing H2. By combining these processes the H2, produced during the anaerobic corrosion of Fe0, could be used by bacteria for further CHC degradation. Therefore the amount of used Fe0 and as a consequence also remediation costs could be reduced. Additionally the continuous supply of H2 could make the bacterial degradation more controllable. Different Fe0 particles (nano- and micro-scale) were tested for their perchloroethene (PCE) degradation rate and H2 production rate in microcosms. PCE-degradation rate by different bacterial cultures was investigated in the same microcosm system. In course of these experiments the 13C enrichment factors of the PCE degradation of the different particles and cultures were determined to enable the differentiation of biotic and abiotic degradation. Preliminary results showed, that the nano-scale particles reacted faster with PCE and water than their micro-scaled counterparts. The PCE degradation via micro-scaled particles lead to 13C enrichment factors in the range of -3,6 ‰ ± 0,6 to -9,5 ‰ ± 0,2. With one of the examined bacterial cultures a fast reduction of PCE to ethene was observed. Although PCE and TCE were completely degraded by this culture the metabolites DCE and VC could still be detected

  1. Assessment of semi-empirical mass transfer correlations for pervaporation treatment of wastewater contaminated with chlorinated hydrocarbons

    Institute of Scientific and Technical Information of China (English)

    LIU Sean X.; PENG Ming

    2006-01-01

    Assessment of mass transfer characteristics of pervaporation (PV) treatment of wastewater contaminated with chlorinated hydrocarbons is of great importance for water treatment plant operators conducting initial evaluation, process optimization,and process economics. While a membrane plays a central role in pervaporation processes and separation efficiency, the mass transfer in the liquid layer next to the membrane surface is of equal, if not greater importance. It is one of the few process parameters that can be adjusted in situ to manipulate the outcome ora pervaporation process. In this study, a bench scale pervaporation experiment of removing a common chlorinated hydrocarbon from water was carried out and the results of it were compared to the ones based on well-known semi-empirical correlations. The mass transfer coefficients from the experiments, ranging from 0.8×10-5~2.5×10-5 m/s under the operating conditions, are higher than those predicted by the correlation. The corresponding separation factors under varying flow velocities are determined to be between 310~950.

  2. Pesticides

    Science.gov (United States)

    ... rodents, noxious weeds, and insects. Pesticides help prevent crop loss and, potentially, human disease. According to the ... pesticides. DO NOT mix pesticides. DO NOT set traps or place bait in areas where children or ...

  3. Transport of polycyclic aromatic hydrocarbons and pesticides during snowmelt within an urban watershed.

    Science.gov (United States)

    Meyer, Torsten; Lei, Ying Duan; Wania, Frank

    2011-01-01

    During snowmelt events in urban watersheds large amounts of organic contaminants are mobilized, potentially affecting the quality of surface and groundwater resources. The transport of polycyclic aromatic hydrocarbons (PAHs) and two pesticides in the highly urbanized Highland Creek watershed within the city of Toronto, Canada, was investigated by sampling river water during two snowmelt periods. The dissolved and the particulate fractions were separately extracted and analyzed. While during normal flow conditions levels of the sum of nine PAHs including phenanthrene, anthracene, fluoranthene, pyrene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, indeno(1,2,3-c,d)pyrene, and benzo(ghi)perylene ranged between 18 and 45 ng/L, concentrations at the onset of melting varied from 550 to 4500 ng/L. Considering enhanced stream discharge rates during snowmelt the contaminant flux in the river increased by three orders of magnitude. The intensity of the melt event largely determined the extent of the PAH concentration increase in the river. The relatively water soluble pesticides chlorothalonil and lindane (γ-HCH) also tended to appear early during melting. Their enrichment in river water may be influenced by the thickness of the snow pack at the onset of melting, and the mode of melt water ablation from the snow pack to the stream, i.e. whether it occurs by overland or sub-surface flow. PMID:21112607

  4. Intrinsic and enhanced bioremediation in aquifers contaminated with chlorinated and aromatic hydrocarbons in The Netherlands

    NARCIS (Netherlands)

    Rijnaarts, H.H.M.; Aalst-van Leeuwen, M.A. van; Heiningen, E. van; Buyzen, H. van; Sinke, A.; Liere, H.C. van; Harkes, M.; Baartmans, R.; Bosma, T.N.P.; Doddema, H.J.

    1998-01-01

    The feasibility of intrinsic and enhanced bioremediation approaches for 16 contaminated sites in the Netherlands are discussed. At at least five out of 10 chlorinated solvent sites, natural attenuation can be used as one of the tools to prevent further dispersion of the plume. At two sites stimulati

  5. SIMULATION OF PERFORMANCE OF CHLORINE-FREE FLURORINATED ETHERS AND FLUORINATED HYDROCARBONS TO REPLACE CFC-11 AND CFC-114 IN CHILLERS

    Science.gov (United States)

    The paper discusses simulation of the performance of chlorine-free fluorinated ethers and fluorinated hydrocarbons as potential long-term replacements for CFC-11 and -114. Modeling has been done with in-house refrigeration models based on the Carnahan-Starling-DeSantis Equation o...

  6. Highly chlorinated toxic contaminants in pesticide-treated wooden art objects.

    Science.gov (United States)

    Covaci, Adrian; Kawaki, Peter; Indekeu, Charles; Schepens, Paul; Neels, Hugo

    2006-01-01

    Although the contamination of wooden art objects with pesticides is well known, to the authors' knowledge no attempt has yet been made to investigate the eventual presence of other toxic compounds that have been produced during the degradation of pesticides or that may be present in the technical formulations. Here, the authors report on the presence of polychlorinated biphenyls (PCBs) and polychlorinated terphenyls (PCTs) in scrapings from wooden antique art objects, namely printing blocks, sculptures, and masks. These antiques belong to 2 fine art museums in Belgium--Antwerp's Ethnographic Museum and the Plantin-Moretus Museum. It is documented that these art objects were treated with pesticides in the 1950s. In addition, 2-heptachlorodibenzo-p-dioxin (HpCDD) isomers and octachlorodibenzo-p-dioxin (OCDD) were also identified. The presence of these toxic compounds in these antiques requires a better understanding of safety for the persons (conservators, museum employees, restorers, and visitors) coming in contact with these objects. PMID:17967745

  7. Concentrations of Polychlorinated Biphenyls (PCB’s), Chlorinated Pesticides, and Heavy Metals and Other Elements in Tissues of Belugas, Delphinapterus leucas, from Cook Inlet

    OpenAIRE

    Becker, Paul R.; Krahn, Margaret M.; Mackey, Elizabeth A.; Demiralp, Rabia; Schantz, Michele M.; Epstein, Michael S.; Donais, Mary Kate; Porter, Barbara J.; Muir, Derek C. G.; Wise, Stephen A.

    2000-01-01

    Tissues from Cook Inlet beluga whales, Delphinapterus leucas, that were collected as part of the Alaska Marine Mammal Tissue Archival Project were analyzed for polychlorinated biphenyls (PCB’s), chlorinated pesticides, and heavy metals and other elements. Concentrations of total PCB’s (ΣPCB’s), total DDT (ΣDDT), chlordane compounds, hexachlorobenzene (HCB), dieldrin, mirex, toxaphene, and hexachlorocyclohexane (HCH) measured in Cook Inlet beluga blubber were compared with those reported for b...

  8. A biogeochemical transport model to simulate the attenuation of chlorinated hydrocarbon contaminant fluxes across the groundwater-surface water interface

    DEFF Research Database (Denmark)

    Malaguerra, Flavio; Binning, Philip John; Albrechtsen, Hans-Jørgen

    2009-01-01

    Chlorinated hydrocarbons originating from point sources are amongst the most prevalent contaminants of ground water and surface water resources. Riparian zones may play an important role in the attenuation of contaminant concentrations when contaminant plumes flow from groundwater to surface water...... because of the occurrence of redox gradients, strongly reductive conditions and high biological activity. In order to meet the expectations of the EU Water Framework Directive, an evaluation of the impact of such plumes on surface water is needed. The aim of this work is to develop a groundwater transport...... number of geochemical processes, allows the simulation of soil geochemical transformations when microbial by-products are released to surface water, and the consideration of non-linear feedbacks on bacterial growth and pollutant transformations. Sensitivity analysis is performed through Monte Carlo...

  9. Fenton process for degradation of selected chlorinated aliphatic hydrocarbons exemplified by trichloroethylene, 1,1-dichloroethylene and chloroform

    Institute of Scientific and Technical Information of China (English)

    Zhimin QIANG; Weiwei BEN; ChinPao HUANG

    2008-01-01

    The degradation of selected chlorinated ali-phatic hydrocarbons (CAHs) exemplified by trichloroethy-lene (TCE), 1,1-dichloroethylene (DCE), and chloroform (CF) was investigated with Fenton oxidation process. The results indicate that the degradation rate was primarily affected by the chemical structures of organic contami-nants. Hydroxyl radicals (·OH) preferred to attack the organic contaminants with an electron-rich structure such as chlorinated alkenes (i.e., TCE and DCE). The dosing mode of Fenton's reagent, particularly of Fe2+, significantly affected the degradation efficiency of studied organic compound. A new "time-squared" kinetic model, C = Coexp(-kobst2), was developed to express the degrada-tion kinetics of selected CAHs. This model was applicable to TCE and DCE, but inapplicable to CF due to their varied reaction rate constants towards ·OH. Chloride release was monitored to examine the degree of dechlorina- tion during the oxidation of selected CAHs. TCE was more easily dechlorinated than DCE and CF. Dichloroacetic acid (DCAA) was identified as the major reaction intermediate in the oxidation of TCE, which could be completely removed as the reaction proceeded. No reaction intermedi- ates or byproducts were identified in the oxidation of DCE and CF. Based on the identified intermediate, the reaction mechanism of TCE with Fenton's reagent was proposed.

  10. Assessment of PCB and chlorinated pesticide accumulation in mussels at Kaštela Bay (Eastern Adriatic).

    Science.gov (United States)

    Milun, Vesna; Grgas, Dijana; Dragičević, Tibela Landeka

    2016-08-15

    The biological response of mussels Mytilus galloprovincialis, resident and transplanted to cages, to contamination with anthropogenic pollutants from Kaštela Bay, located in the central part of the eastern Adriatic coast, was investigated. The main purpose of this paper is to trace the accumulation of PCBs and chlorinated pesticides (HCB, lindane, heptachlor, aldrin, p,p'-DDTs) as a direct measure of potential contaminant availability to organisms, in a period from 2000 to 2011. In order to do so, cultured mussels (Mytilus galloprovincialis) of the same size and age were transplanted from the unpolluted Mali Ston Bay to the Kaštela Bay. Sampling was performed bimonthly, and the level of target contaminants in whole soft tissue was determined. After two months of exposure, the concentration of PCBs in transplanted mussels increased on average 6.5-times, and of DDTs 2-times, while the intensity of changes for HCB, lindane, heptachlor and aldrin was negligible. Seasonal variation of pesticide content was similar without a significant change throughout the experimental period, while that of PCBs was somewhat different showing increased accumulation in summer. Seasonal and spatial variation of organochlorines in the Kaštela Bay was likely the result of prevailing environmental rather than biological parameters. In accordance with prevailing hydrodynamic cycling, contaminant concentration decreased in acyclonic direction towards the exit of the Bay. Measurement of target contaminants in resident mussels sampled from the most contaminated area of the Bay exhibited decreasing concentrations of lindane, aldrin and p,p'-DDTs. However, PCBs exhibited statistically significant increasing concentrations in relation to the slightly increasing concentrations of HCB. With regard to human health, organochlorine (OC) levels in the mussel tissue were below prescribed limits for human consumption. PMID:27096632

  11. Prediction of gas chromatography/electron capture detector retention times of chlorinated pesticides, herbicides, and organohalides by multivariate chemometrics methods

    International Nuclear Information System (INIS)

    A quantitative structure-retention relationship (QSRR) study, has been carried out on the gas chromatograph/electron capture detector (GC/ECD) system retention times (t Rs) of 38 diverse chlorinated pesticides, herbicides, and organohalides by using molecular structural descriptors. Modeling of retention times of these compounds as a function of the theoretically derived descriptors was established by multiple linear regression (MLR) and partial least squares (PLS) regression. The stepwise regression using SPSS was used for the selection of the variables that resulted in the best-fitted models. Appropriate models with low standard errors and high correlation coefficients were obtained. Three types of molecular descriptors including electronic, steric and thermodynamic were used to develop a quantitative relationship between the retention times and structural properties. MLR and PLS analysis has been carried out to derive the best QSRR models. After variables selection, MLR and PLS methods used with leave-one-out cross validation for building the regression models. The predictive quality of the QSRR models were tested for an external prediction set of 12 compounds randomly chosen from 38 compounds. The PLS regression method was used to model the structure-retention relationships, more accurately. However, the results surprisingly showed more or less the same quality for MLR and PLS modeling according to squared regression coefficients R 2 which were 0.951 and 0.948 for MLR and PLS, respectively

  12. California sea lions (Zalophus californianus californianus) have lower chlorinated hydrocarbon contents in northern Baja California, Mexico, than in California, USA

    Energy Technology Data Exchange (ETDEWEB)

    Del Toro, Ligeia [Universidad Autonoma de Baja California (UABC), Facultad de Ciencias Marinas, Ensenada, Baja California (Mexico); Investigacion y Conservacion de Mamiferos Marinos de Ensenada, A.C., Placido Mata 2309 Depto. D-5, Condominio Las Fincas, Ensenada, Baja California 22810 (Mexico); Heckel, Gisela [Investigacion y Conservacion de Mamiferos Marinos de Ensenada, A.C., Placido Mata 2309 Depto. D-5, Condominio Las Fincas, Ensenada, Baja California 22810 (Mexico) and Centro de Investigacion Cientifica y de Educacion Superior de Ensenada, B.C. Km 107 Carretera Tijuana-Ensenada, Ensenada, Baja California 22860 (Mexico)]. E-mail: gheckel@cicese.mx; Camacho-Ibar, Victor F. [Instituto de Investigaciones Oceanologicas, UABC, Apdo. Postal 453, Ensenada, Baja California 22860 (Mexico); Schramm, Yolanda [Universidad Autonoma de Baja California (UABC), Facultad de Ciencias Marinas, Ensenada, Baja California (Mexico); Investigacion y Conservacion de Mamiferos Marinos de Ensenada, A.C., Placido Mata 2309 Depto. D-5, Condominio Las Fincas, Ensenada, Baja California 22810 (Mexico)

    2006-07-15

    Chlorinated hydrocarbons (CHs) were determined in blubber samples of 18 California sea lions (Zalophus californianus californianus) that stranded dead along Todos Santos Bay, Ensenada, Baja California, Mexico, January 2000-November 2001. {sigma}DDTs were the dominant group (geometric mean 3.8 {mu}g/g lipid weight), followed by polychlorinated biphenyls ({sigma}PCBs, 2.96 {mu}g/g), chlordanes (0.12 {mu}g/g) and hexachlorocyclohexanes (0.06 {mu}g/g). The {sigma}DDTs/{sigma}PCBs ratio was 1.3. We found CH levels more than one order of magnitude lower than those reported for California sea lion samples collected along the California coast, USA, during the same period as our study. This sharp north-south gradient suggests that Z. californianus stranded in Ensenada (most of them males) would probably have foraged during the summer near rookeries 500-1000 km south of Ensenada and the rest of the year migrate northwards, foraging along the Baja California peninsula, including Ensenada, and probably farther north. - Results suggest that sea lion prey must also have lower hydrocarbons in Baja California than in California in the USA.

  13. An in situ intercomparison exercise on passive samplers for monitoring metals, polycyclic aromatic hydrocarbons and pesticides in surface waters

    OpenAIRE

    Miège, C.; Mazzella, N.; Schiavone, S.; Dabrin, A.; Berho, C.; Ghestem, J.P.; Gonzalez, C.; Gonzalez, J L; Lalere, B.; Lardy Fontan, S.; Lepot, B.; Munaron, D.; Tixier, C.; Togola, A.; Coquery, M.

    2012-01-01

    An intercomparison exercise on passive samplers (PSs) was organized in summer 2010 for the measurement of selected metals, polycyclic aromatic hydrocarbons (PAHs) and pesticides in surface waters. Various PSs were used and compared at 2 rivers sites and one marine lagoon. A total of 24 laboratories participated. We present selected significant outputs from this exercise, including discussion on quality assurance and quality control for PSs, the interlaboratory variability of field blanks, tim...

  14. Chlorinated biphenyls and pesticides in migrating and resident seabirds from East and West Antarctica.

    Science.gov (United States)

    Corsolini, Simonetta; Borghesi, Nicoletta; Ademollo, Nicoletta; Focardi, Silvano

    2011-11-01

    The unhatched eggs of the following seabirds were analyzed to quantify PCBs, hexachlorobenzene (HCB), α-, β-, γ-, δ-hexachlorocyclohexanes (HCHs), o,p' and p,p' isomers of DDT, DDD and DDE: resident Adèlie (Pygoscelis adèliae, ADPE) and Emperor (Aptenodytes forsteri, EMPE) penguins, migrating snow petrel (Pagodroma nivea, SNPT) and South Polar skua (Catharacta maccormicki, SPSK) from the Ross Sea (East Antarctica); and migrating Brown skua (Catharacta antartica, BRSK) and resident ADPE from the Brainsfield Strait (West Antarctica). The general aims were to evaluate the contaminant accumulation in eggs of migrating and resident species in the two study areas, and to compare levels in penguins and skuas nesting in East and West Antarctica. PCB congener and HCH and DDT isomer profiles were also assessed. Comparisons were evaluated using seven PCB congeners (IUPAC nos. 28, 52, 101, 118+149, 138, 153, and 180), p,p'-DDE, ΣDDTs, and ΣHCHs. Higher contaminant concentrations were detected in migrating seabirds (South polar skua and brown skua)>sub-Antarctic species (snow petrel)>Antarctic species (penguins) from both the sampling sites, suggesting contamination events at lower latitudes for those birds migrating northward. HCHs showed the lowest concentrations in all species (from 0.03±0.03 ng/g wet wt in SPSK to 1.81±1.23 ng/g wet wt in ADPE from West Antarctica), and PCBs were the most abundant contaminants (from 4.34±2.15 ng/g wet wt. in EMPE to 53.41±19.61 ng/g wet wt. in brown skua). Among pesticides, it is relevant the detection of p,p'-DDT in Adèlie penguin from West Antarctica and in both species of skua; the detection of this pesticide can confirm its actual use in certain malaria-endemic countries from where it is transferred through the long range transport to the polar regions. Contaminants did not show any significant temporal trend during a ten year time span, from 1994/95 to 2004/05, in organisms collected in East Antarctica and they did not

  15. Chlorinated pesticides and cancer of the head and neck: a retrospective case series.

    Science.gov (United States)

    Govett, Gregg; Genuis, Stephen John; Govett, Hannah E; Beesoon, Sanjay

    2011-07-01

    Cancer of the head and neck is a pervasive problem with recognized determinants including tobacco use, alcohol consumption, and earlier radiation exposure. Organochlorine pesticides (OCPs) have been shown to have carcinogenic potential in both animals and humans. OCPs have previously been widely used in the agricultural industry of rural Oklahoma. Seven patients from rural Oklahoma with head and neck cancer and without any of the usual risk factors were tested for the presence of OCPs in their adipose tissue. Clinical and toxicological data on each of these patients are presented for consideration. Results were compared with (i) levels from five individuals not experiencing cancer but who lived in the same area, and (ii) adipose tissue OCP levels in other population groups. Each of the seven patients tested had markedly elevated levels of some OCPs in their adipose tissue compared with the cohort of noncancer patients. Further research is required to confirm whether there is a causative link between OCP bioaccumulation and head and neck cancer as suggested by this case series. PMID:21633202

  16. Chlorinated pesticides in the bodies of dolphins of the French Mediterranean coastal environment

    Directory of Open Access Journals (Sweden)

    Emmanuel Wafo

    2012-06-01

    Full Text Available The concentrations of organochlorinated pesticides including lindane, heptachlor, aldrin, heptachlor-epoxide, endosulfan I, dieldrin,and endrin were determinated in striped dolphins (Stenella coeruleoalba (n = 26, and 2 bottlenose dolphins (Tursiops truncates (n = 2,stranded on the French Mediterranean coasts. Studies are carried out on the lung, the muscle, the kidney, the liver, and the blubber. The concentrationsof all the analysed compounds were detected to variable levels in each tissue and organ. In blubber, dieldrin is generally the mostabundant coumpound (215.3 ± 290.3 ng g-1 lw, followed by endrin (207.7 ± 217.5 ng g-1 lw, heptachlor-epoxid (106.6 ± 107.1 ng g-1 lw, endosulfanI (46.6 ± 32.8 ng g-1 lw, lindane (16.6 ± 12.1 ng g-1 lw, aldrin (11.9 ± 8.4 ng g-1 lw and heptachlor (6.7 ± 4.2 ng g-1 lw. These valuesare comparable to those previously obtained by other authors during the years 1990.

  17. Comparison of different extraction techniques for the determination of chlorinated pesticides in animal feed.

    Science.gov (United States)

    Gfrerer, Marion; Chen, Shuo; Lankmayr, Ernst P; Quan, Xie; Yang, Fenglin

    2004-04-01

    The performances of Soxhlet extraction, dive-in Soxhlet extraction, microwave-assisted extraction (MAE), accelerated solvent extraction (ASE), fluidized-bed extraction (FBE), and ultrasonic extraction (UE) for the analysis of organochlorine pesticides in animal feed have been investigated. ASE and MAE provided significantly better extraction efficiency than Soxhlet extraction. The concentrations were 126.7 and 114.8%, respectively, of the values obtained by classical Soxhlet extraction, whereas the results from FBE and dive-in Soxhlet were comparable with those from the standard Soxhlet procedure. The reproducibility of FBE was the best, with RSDs ranging from 0.3 to 3.9%. Under the investigated operation conditions UE was not efficient, with the recoveries of target compounds being about 50% less than Soxhlet. Additionally, the performances of Soxhlet, dive-in Soxhlet, MAE, ASE and FBE were validated by determination of the certified reference material BCR-115. The results from the extraction techniques were in good agreement with the certified values. PMID:14762649

  18. Natural attenuation of chlorinated-hydrocarbon contamination at Fort Wainwright, Alaska; a hydrogeochemical and microbiological investigation workplan

    Science.gov (United States)

    McCarthy, Kathleen A.; Lilly, Michael R.; Braddock, Joan F.; Hinzman, Larry D.

    1998-01-01

    Natural attenuation processes include biological degradation, by which microorganisms break down contaminants into simpler product compounds; adsorption of contaminants to soil particles, which decreases the mass of contaminants dissolved in ground water; and dispersion, which decreases dissolved contaminant concentrations through dilution. The primary objectives of this study are to (1) assess the degree to which such natural processes are attenuating chlorinated-hydrocarbon contamination in ground water, and (2) evaluate the effects of ground-water/surface-water interactions on natural-attenuation processes in the area of the former East and West Quartermasters Fueling Systems for Fort Wainwright, Alaska. The study will include investigations of the hydrologic, geochemical, and microbiological processes occurring at this site that influence the transport and fate of chlorinated hydrocarbons in ground water. To accomplish these objectives, a data-collection program has been initiated that includes measurements of water-table elevations and the stage of the Chena River; measurements of vertical temperature profiles within the subsurface; characterization of moisture distribution and movement in the unsaturated zone; collection of ground-water samples for determination of both organic and inorganic chemical constituents; and collection of ground-water samples for enumeration of microorganisms and determination of their potential to mineralize contaminants. We will use results from the data-collection program described above to refine our conceptual model of hydrology and contaminant attenuation at this site. Measurements of water-table elevations and river stage will help us to understand the magnitude and direction of ground-water flow and how changes in the stage of the Chena River affect ground-water flow. Because ambient ground water and surface water typically have different temperature characteristics, temperature monitoring will likely provide further insight

  19. Diabetes Prevalence in Relation to Serum Concentrations of Polychlorinated Biphenyl (PCB) Congener Groups and Three Chlorinated Pesticides in a Native American Population

    Science.gov (United States)

    Aminov, Zafar; Haase, Richard; Rej, Robert; Schymura, Maria J.; Santiago-Rivera, Azara; Morse, Gayle; DeCaprio, Anthony; Carpenter, David O.

    2016-01-01

    Background: Exposure to persistent organic pollutants (POPs) is known to increase risk of diabetes. Objective: To determine which POPs are most associated with prevalence of diabetes in 601 Akwesasne Native Americans. Methods: Multiple logistic regression analysis was used to assess associations between quartiles of concentrations of 101 polychlorinated biphenyl (PCBs) congeners, congener groups and three chlorinated pesticides [dichlorodiphenyldichloroethylene (DDE), hexachlorobenzene (HCB) and mirex] with diabetes. In Model 1, the relationship between quartiles of exposure and diabetes were adjusted only for sex, age, body mass index (BMI), and total serum lipids. Model 2 included additional adjustment for either total PCBs or total pesticides. Results: Total serum PCB and pesticide concentrations were each significantly associated with prevalence of diabetes when adjusted only for covariates (Model 1), but neither showed a significant OR for highest to lowest quartiles after additional adjustment for the other (Model 2). When applying Model 2 to PCB congener groups and individual pesticides, there were significant omnibus differences between the four quartiles (all ps pesticides in a Native American population. Environ Health Perspect 124:1376–1383; http://dx.doi.org/10.1289/ehp.1509902 PMID:27035469

  20. Simulation of ground-water flow and transport of chlorinated hydrocarbons at Graces Quarters, Aberdeen Proving Ground, Maryland

    Science.gov (United States)

    Tenbus, Frederick J.; Fleck, William B.

    2001-01-01

    Military activity at Graces Quarters, a former open-air chemical-agent facility at Aberdeen Proving Ground, Maryland, has resulted in ground-water contamination by chlorinated hydrocarbons. As part of a ground-water remediation feasibility study, a three-dimensional model was constructed to simulate transport of four chlorinated hydrocarbons (1,1,2,2-tetrachloroethane, trichloroethene, carbon tetrachloride, and chloroform) that are components of a contaminant plume in the surficial and middle aquifers underlying the east-central part of Graces Quarters. The model was calibrated to steady-state hydraulic head at 58 observation wells and to the concentration of 1,1,2,2-tetrachloroethane in 58 observation wells and 101direct-push probe samples from the mid-1990s. Simulations using the same basic model with minor adjustments were then run for each of the other plume constituents. The error statistics between the simulated and measured concentrations of each of the constituents compared favorably to the error statisticst,1,2,2-tetrachloroethane calibration. Model simulations were used in conjunction with contaminant concentration data to examine the sources and degradation of the plume constituents. It was determined from this that mixed contaminant sources with no ambient degradation was the best approach for simulating multi-species solute transport at the site. Forward simulations were run to show potential solute transport 30 years and 100 years into the future with and without source removal. Although forward simulations are subject to uncertainty, they can be useful for illustrating various aspects of the conceptual model and its implementation. The forward simulation with no source removal indicates that contaminants would spread throughout various parts of the surficial and middle aquifers, with the100-year simulation showing potential discharge areas in either the marshes at the end of the Graces Quarters peninsula or just offshore in the estuaries. The

  1. Local and seasonal variations in concentrations of chlorinated polycyclic aromatic hydrocarbons associated with particles in a Japanese megacity.

    Science.gov (United States)

    Ohura, Takeshi; Kamiya, Yuta; Ikemori, Fumikazu

    2016-07-15

    Concentrations of particle-bound polycyclic aromatic hydrocarbons (PAHs) and chlorinated PAHs (ClPAHs) were measured in different seasons at five sampling stations in Nagoya, a Japanese megacity. The annual mean total ClPAH and total PAH concentrations were 43.3-92.6pg/m(3) and 5200-8570pg/m(3), respectively. The concentrations of total ClPAHs were significantly variable than those of total PAHs, and both total concentrations through the seasons did not significantly correlate at any of the stations. Principal component analysis was used to characterize the ClPAH sources, resulted that ClPAHs were found to be associated with the sources of high-molecular-weight PAHs in the warmer seasons and of low-molecular-weight PAHs in the colder seasons. These findings suggest that principal sources of particle-bound ClPAHs are present in the local area, and change in the seasons. Toxic equivalent (TEQ) concentrations were estimated to assess the risks associated with exposure to ClPAHs in air. The TEQ concentrations in the samples were 0.05-0.32pg-TEQ/m(3). The TEQ concentrations in summer were approximately half the TEQ concentrations in the other seasons at all of the stations. PMID:27037480

  2. Chlorinated hydrocarbons in tuna homogenate IAEA-351: Results of a world-wide exercise. ILMR intercalibration exercise report no. 44

    International Nuclear Information System (INIS)

    The present intercalibration exercise provides, once again, strong evidence for insufficient data quality for chlorinated hydrocarbons in marine samples. This comment must be considered in perspective. The principle aim of these exercises is not just to obtain narrower confidence intervals for a given parameter moreover it is to guarantee that the data generated by monitoring exercises is of sufficient quality to evaluate contaminant levels, gradients and trends in the environment. All data should be accurate but precision (expressed as confidence limits) may vary according to its application. It is clearly not the same problem to measure DDT for human health protection (legal concentration limits in seafood range from about 1000-5000 ng/g) as it is to monitor environmental trends where values in biota are commonly one to three orders of magnitude lower. Even the 8 laboratories achieving 'good' data for pp'DDT would not be able to statistically distinguish a 35% increase of the concentration of this parameter from 30-41 ng/g on the basis of the precision observed in the present exercise. Fortunately spatial gradients for DDTs tend to be much larger than this and significant changes could be easily detected by the 'good' labs provided that they use adequate quality control procedures

  3. Organophosphorus (OP) Pesticide Degradation in the Presence of Chlorinated Oxidants: Kinetics, Modeling, and Structure-Activity Relationships

    Science.gov (United States)

    The rates and pathways for pesticide transformation during drinking water treatment are known for only a few pesticides and under limited conditions. The resulting oxons are more toxic than the parent pesticides. The transformation rates and pathways for chlorpyrifos, an OP pest...

  4. Evaluation of hydrocarbons and organochlorine pesticides and their tolerant microorganisms from an agricultural soil to define its bioremediation feasibility.

    Science.gov (United States)

    Islas-García, Alejandro; Vega-Loyo, Libia; Aguilar-López, Ricardo; Xoconostle-Cázares, Beatriz; Rodríguez-Vázquez, Refugio

    2015-01-01

    The concentrations of hydrocarbons and organochlorine pesticides (OCPs), nutrients and tolerant microorganisms in an agricultural soil from a locality in Tepeaca, Puebla, Mexico, were determined to define its feasibility for bioremediation. The OCPs detected were heptachlor, aldrin, trans-chlordane, endosulfán I, endosulfán II, 1,1,1-bis-(4-chlorophenyl)-2,2-trichloroethane (4,4'-DDT), 1,1-bis-(4-chlorophenyl)-2,2-dichloroethene (4,4'-DDE) and endrin aldehyde, with values of 0.69-30.81 ng g(-1). The concentration of hydrocarbons in the soil of Middle Hydrocarbons Fraction (MHF), C10 to C28, was 4608-27,748 mg kg(-1) and 1117-19,610 mg kg(-1) for Heavy Hydrocarbons Fraction (HHF), C28 to C35, due to an oil spill from the rupture of a pipeline. The soil was deficient in nitrogen (0.03-0.07%) and phosphorus (0 ppm), and therefore it was advisable to fertilize to bio-stimulate the native microorganisms of soil. In the soil samples, hydrocarbonoclast fungi 3.72 × 10(2) to 44.6 × 10(2) CFU g(-1) d.s. and hydrocarbonoclast bacteria (0.17 × 10(5) to 8.60 × 10(5) CFU g(-1) d.s.) were detected, with a tolerance of 30,000 mg kg(-1) of diesel. Moreover, pesticideclast fungi (5.13 × 10(2) to 42.2 × 10(2) CFU g(-1) d.s.) and pesticideclast bacteria (0.15 × 10(5) to 9.68 × 10(5) CFU g(-1) d.s.) were determined with tolerance to 20 mg kg(-1) of OCPs. Fungi and bacteria tolerant to both pollutants were also quantified. Therefore, native microorganisms had potential to be stimulated to degrade hydrocarbons and pesticides or both pollutants. The concentration of pollutants and the microbial activity analyzed indicated that bioremediation of the soil contaminated with hydrocarbons and pesticides using bio-stimulation of native microorganisms was feasible.

  5. Evaluation of hydrocarbons and organochlorine pesticides and their tolerant microorganisms from an agricultural soil to define its bioremediation feasibility.

    Science.gov (United States)

    Islas-García, Alejandro; Vega-Loyo, Libia; Aguilar-López, Ricardo; Xoconostle-Cázares, Beatriz; Rodríguez-Vázquez, Refugio

    2015-01-01

    The concentrations of hydrocarbons and organochlorine pesticides (OCPs), nutrients and tolerant microorganisms in an agricultural soil from a locality in Tepeaca, Puebla, Mexico, were determined to define its feasibility for bioremediation. The OCPs detected were heptachlor, aldrin, trans-chlordane, endosulfán I, endosulfán II, 1,1,1-bis-(4-chlorophenyl)-2,2-trichloroethane (4,4'-DDT), 1,1-bis-(4-chlorophenyl)-2,2-dichloroethene (4,4'-DDE) and endrin aldehyde, with values of 0.69-30.81 ng g(-1). The concentration of hydrocarbons in the soil of Middle Hydrocarbons Fraction (MHF), C10 to C28, was 4608-27,748 mg kg(-1) and 1117-19,610 mg kg(-1) for Heavy Hydrocarbons Fraction (HHF), C28 to C35, due to an oil spill from the rupture of a pipeline. The soil was deficient in nitrogen (0.03-0.07%) and phosphorus (0 ppm), and therefore it was advisable to fertilize to bio-stimulate the native microorganisms of soil. In the soil samples, hydrocarbonoclast fungi 3.72 × 10(2) to 44.6 × 10(2) CFU g(-1) d.s. and hydrocarbonoclast bacteria (0.17 × 10(5) to 8.60 × 10(5) CFU g(-1) d.s.) were detected, with a tolerance of 30,000 mg kg(-1) of diesel. Moreover, pesticideclast fungi (5.13 × 10(2) to 42.2 × 10(2) CFU g(-1) d.s.) and pesticideclast bacteria (0.15 × 10(5) to 9.68 × 10(5) CFU g(-1) d.s.) were determined with tolerance to 20 mg kg(-1) of OCPs. Fungi and bacteria tolerant to both pollutants were also quantified. Therefore, native microorganisms had potential to be stimulated to degrade hydrocarbons and pesticides or both pollutants. The concentration of pollutants and the microbial activity analyzed indicated that bioremediation of the soil contaminated with hydrocarbons and pesticides using bio-stimulation of native microorganisms was feasible. PMID:25587779

  6. Organochlorine pesticides, chlorinated dioxins and furans, and PCBs in peregrine falcon Falco peregrinus eggs from the Kola peninsula, Russia

    Science.gov (United States)

    Henny, C.J.; Ganusevich, S.A.; Ward, F.P.; Schwartz, T.R.

    1994-01-01

    Nesting of a bog-associated population of mlgfatory Peregrine Falcons, Falco peregrinus, along the Ponoy River depression, Kola Peninsula, Russia, has been studied since 1977. In 1987 91 production rates averaged 1.94 young per active nest and the number of breeding pairs increased from 4 to 10. In 1991, most eyrie sites were visited during the egg stage and a 'sample' egg was collected for contaminant analysis. Eight Peregrine Falcon eggs contained relatively low concentrations of p,p' -DOE (DOE) (geometric mean 3.5 g/g) and of other organochlorine pesticides. These DOE concentrations are similar to those reported in Peregrine Falcon eggs from an Alaskan population that had also showed a recent population increase. Eggshell thinning (11.4%) was similar to that found in Alaska. Concentrations of polychlorinated biphenyls (PCBs) were higher than DOE concentrations, comparable to the contamination profile shown by Peregrine Falcon populations in Fennoscandia, and were higher than those found in Alaskan birds. Before this study, no Peregrine Falcon eggs from Russia had 'been analyzed for PCB congeners, polychlorinated dibenzo- p-dioxins (PCDDs), or pol ychlorinated dibenzofurans (PCD Fs). Conversions of analytical concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), other PCDDs, PCDFs and PCB congeners based on relative aryl hydrocarbon hydroxylase induction potencies allowed the estimation of total 2,3,7,8- TCDD equivalents (TEQs). The TEQs are in the range that is associated with embryonic mortality in other species. Even though the Peregrine Falcon population now seems to be released from decades of a DOT problem, exposure to other contaminant continues. There is an obvious need to assess further the sources and longer-term trends of the PCBs. We also report residue concentrations from one White-tailed Eagle, Haliaeetus albicilla, egg.

  7. Levels of Polycyclic Aromatic Hydrocarbons, Polychlorinated Biphenyls, and Organochlorine Pesticides in Various Tissues of White-Backed Vulture in India

    OpenAIRE

    Dhananjayan, V.; Muralidharan, S

    2013-01-01

    This study provides information on the current status of contamination by polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs) in the tissues of endangered White-backed Vulture Gyps bengalensis in India. Chemical analyses revealed detectable amounts of PAHs, PCBs, and OCPs. Concentration ranges of ∑ PAHs, ∑ PCBs, and ∑ OCPs in tissues were 60–2037 ng/g, 30–5790 ng/g, and 3.2–5836 ng/g wet weight, respectively. 1,1-Dichloro-2,2-bis(p-c...

  8. Intercalibration of analytical methods on marine environmental samples. Results of MEDPOL-II exercise for the intercalibration of chlorinated hydrocarbon measurements on mussel homogenate (MA-M-2/OC)

    International Nuclear Information System (INIS)

    Mussels have been considered as good indicators of chlorinated hydrocarbon pollution of the marine environment and this led to the development of mussel watch programmes in many countries in the late seventies. These intercalibration exercises were arranged in order to increase the quality of analytical capabilities of environmental laboratories. The samples MA-M-2/0C of Mediterranean mussels with chlorinated hydrocarbon content were checked by 27 laboratories. It was judged highly suitable for these laboratories to have at their disposal a reference material made of mussel tissue with robust estimations of the true values with respect to several chlorinated hydrocarbons. Such a material would allow chemists to check the validity of new analytical procedures

  9. Technology assessment: Chlorine chemistry

    International Nuclear Information System (INIS)

    Chlorine is not just one of many chemical feedstocks which is used in a few definitely harmful products like PVC or CFC but is irrelevant in all other respects. Just the opposite is true: There is hardly any product line of the chemical industry that can do without chlorine, from herbicides and pesticides to dyes, plastics, pharmaceuticals, photographic atricles, and cosmetics. Chlorine is not only a key element of chemical production but also an ubiquitous element of everyday life in civilisation. There are even many who would agree that the volume of chlorine production is an indicator of the competitive strength and national wealth of a modern society. By now, however, it has become evident that the unreflected use of chlorine is no longer ecologically acceptable. The consequences of a chlorine phase-out as compared to the continued chlorine production at the present level were investigated scientifically by a PROGNOS team. They are presented in this book. (orig.)

  10. Geological and hydrogeological features affecting migration, multi-phase partitioning and degradation of chlorinated hydrocarbons through unconsolidated porous media.

    OpenAIRE

    Filippini, Maria

    2015-01-01

    Chlorinated solvents are the most ubiquitous organic contaminants found in groundwater since the last five decades. They generally reach groundwater as Dense Non-Aqueous Phase Liquid (DNAPL). This phase can migrate through aquifers, and also through aquitards, in ways that aqueous contaminants cannot. The complex phase partitioning to which chlorinated solvent DNAPLs can undergo (i.e. to the dissolved, vapor or sorbed phase), as well as their transformations (e.g. degradation), depend on the...

  11. Membrane filtration process and bioreactor for elimination of chlorinated hydrocarbons from industrial effluents; Membranfiltration und Bioreaktor zur Eliminierung chlorierter Kohlenwasserstoffe aus Industrieabwaessern

    Energy Technology Data Exchange (ETDEWEB)

    Schierenbeck, A.

    2003-07-01

    Selective separation and elimination of chlorinated hydrocarbons from industrial effluents directly at the production site was to be achieved by a combined process including membrane technology and biodegradation. This way, closed cycle processes can be designed which will be a major contribution to environmental protection integrated in production processes. First, chlorinated hydrocarbons are characterized in terms of occurrence and biodegradability. Two model substances are discussed (3-chlorobenzoic acid and 4-chlorophenol), and a practical example is presented. The fundamentals of the processes used for treatment of industrial effluents are outlined, and their advantages and shortcomings are discussed, with particular regard to integrated application in production processes. [German] Das Ziel dieser Arbeit ist die Entwicklung einer Verfahrenstechnik, bei der durch die Kombination der Membrantechnik mit dem biologischen Abbau die selektive Abtrennung und Eliminierung chlorierter Kohlenwasserstoffe aus dem Industrieabwasser schon am Ort des Entstehens realisiert werden. Durch den Einsatz dieser Technik wird die Schliessung von Wasserkreislaeufen moeglich. Dies stellt fuer alle Bereiche, in denen chlorierte Kohlenwasserstoffe in das Abwasser gelangen koennen, einen wichtigen Beitrag zum produktionsintegrierten Umweltschutz dar. Dazu wird zunaechst die Problemstoffgruppe der chlorierten Kohlenwasserstoffe hinsichtlich ihres Auftretens und der biologischen Abbaubarkeit charakterisiert. Zwei Modellsubstanzen (3-Chlorbenzoesaeure und 4-Chlorphenol) werden diskutiert sowie ein Beispiel aus der Praxis vorgestellt, bei dem ein Abwasser mit chlorierten Kohlenwasserstoffen anfaellt. Die Grundlagen der verwendeten Verfahren zur Behandlung von Industrieabwaessern mit entsprechenden Abwasserinhaltsstoffen werden dargestellt. Die Moeglichkeiten und Grenzen dieser Verfahren, insbesondere im Hinblick auf den produktionsintegrierten Einsatz, werden diskutiert. (orig.)

  12. 有机氯农药微生物降解技术研究进展%Progress in Degradation of Organo-chlorinated Pesticides by Microorganism

    Institute of Scientific and Technical Information of China (English)

    卢向明; 陈萍萍

    2012-01-01

    文章综述了有机氯农药的污染化学特征、环境介质中的分布水平、降解功能微生物的种类以及典型有机氯农药的降解途径等,并对有机氯农药微生物降解相关的酶和基因以及降解机理进行了重点讨论.参与有机氯农药微生物降解过程的酶主要有脱氯化氢酶、水解酶和脱氢酶三种,它们通过共代谢,中间协同代谢或矿化等作用完成降解过程.相关降解基因主要是Lin家族基因,包括LinA~LinJ的10个典型功能基因编码.微生物降解有机氯农药的机理主要包括矿化作用、共代谢作用、种间协同代谢作用、活化作用和间接作用等,其中矿化过程包括氧化、还原、水解、脱水、脱卤和裂解等生化反应.由于有机氯农药的持久性和广泛污染性,其降解机理及中间产物的类型、毒性以及新型降解菌的效能开发仍是该领域今后的研究重点.%This paper reviewed the recent research advances in organo-chlorinated pesticide degradation by microorganism, focusing on topics such as enzyme, gene and the biodegradation mechanism. Main enzymes introduced in this paper refered to de-hydro-chlorination enzyme, hydrolytic enzyme and dehydrogenase, and the genes related were ten Lin family genes including the typical functional codes from Lin A to J. Owing to the difficulties involved in controlling pollution of organo-chlorinated pesticides in terms of their extent of application and persistence in the environment, the paper made suggestions for strengthening the research in this area.

  13. Effects of currently used pesticides and their mixtures on the function of thyroid hormone and aryl hydrocarbon receptor in cell culture

    Energy Technology Data Exchange (ETDEWEB)

    Ghisari, Mandana; Long, Manhai; Tabbo, Agnese; Bonefeld-Jørgensen, Eva Cecilie, E-mail: ebj@mil.au.dk

    2015-05-01

    Evidence suggest that exposure to pesticides can interfere with the endocrine system by multiple mechanisms. The endocrine disrupting potential of currently used pesticides in Denmark was analyzed as single compounds and in an equimolar mixture of 5 selected pesticides. The pesticides were previously analyzed for effects on the function of estrogen and androgen receptors, the aromatase enzyme and steroidogenesis in vitro. In this study, the effect on thyroid hormone (TH) function and aryl hydrocarbon receptor (AhR) transactivity was assessed using GH3 cell proliferation assay (T-screen) and AhR responsive luciferase reporter gene bioassay, respectively. Thirteen pesticides were analyzed as follows: 2-methyl-4-chlorophenoxyacetic acid, terbuthylazine, iodosulfuron-methyl-sodium, mesosulfuron-methyl, metsulfuron-methyl, chlormequat chloride, bitertanol, propiconazole, prothioconazole, mancozeb and its metabolite ethylene thiourea, cypermethrin, tau-fluvalinate, and malathion (currently banned in DK). In the T-screen, prothioconazole, malathion, tau-fluvalinate, cypermethrin, terbuthylazine and mancozeb significantly stimulated and bitertanol and propiconazole slightly reduced the GH3 cell proliferation. In the presence of triiodothyronine (T3), prothioconazole, tau-fluvalinate, propiconazole, cypermethrin and bitertanol significantly antagonized the T3-induced GH3 cell proliferation. Eleven of the tested pesticides agonized the AhR function, and bitertanol and prothioconazole inhibited the basal AhR activity. Bitertanol, propiconazole, prothioconazole and cypermethrin antagonized the TCDD-induced AhR transactivation at the highest tested concentration. The 5-component mixture had inducing effect but the combined effect could not be predicted due to the presence of bitertanol eliciting inhibitory effect. Upon removal of bitertanol from the mixture, the remaining four pesticides acted additively. In conclusion, our data suggest that pesticides currently used in Denmark

  14. Effects of currently used pesticides and their mixtures on the function of thyroid hormone and aryl hydrocarbon receptor in cell culture

    International Nuclear Information System (INIS)

    Evidence suggest that exposure to pesticides can interfere with the endocrine system by multiple mechanisms. The endocrine disrupting potential of currently used pesticides in Denmark was analyzed as single compounds and in an equimolar mixture of 5 selected pesticides. The pesticides were previously analyzed for effects on the function of estrogen and androgen receptors, the aromatase enzyme and steroidogenesis in vitro. In this study, the effect on thyroid hormone (TH) function and aryl hydrocarbon receptor (AhR) transactivity was assessed using GH3 cell proliferation assay (T-screen) and AhR responsive luciferase reporter gene bioassay, respectively. Thirteen pesticides were analyzed as follows: 2-methyl-4-chlorophenoxyacetic acid, terbuthylazine, iodosulfuron-methyl-sodium, mesosulfuron-methyl, metsulfuron-methyl, chlormequat chloride, bitertanol, propiconazole, prothioconazole, mancozeb and its metabolite ethylene thiourea, cypermethrin, tau-fluvalinate, and malathion (currently banned in DK). In the T-screen, prothioconazole, malathion, tau-fluvalinate, cypermethrin, terbuthylazine and mancozeb significantly stimulated and bitertanol and propiconazole slightly reduced the GH3 cell proliferation. In the presence of triiodothyronine (T3), prothioconazole, tau-fluvalinate, propiconazole, cypermethrin and bitertanol significantly antagonized the T3-induced GH3 cell proliferation. Eleven of the tested pesticides agonized the AhR function, and bitertanol and prothioconazole inhibited the basal AhR activity. Bitertanol, propiconazole, prothioconazole and cypermethrin antagonized the TCDD-induced AhR transactivation at the highest tested concentration. The 5-component mixture had inducing effect but the combined effect could not be predicted due to the presence of bitertanol eliciting inhibitory effect. Upon removal of bitertanol from the mixture, the remaining four pesticides acted additively. In conclusion, our data suggest that pesticides currently used in Denmark

  15. Monitoring organo chlorine pesticides in surface and ground water in San Juan (Argentina); Determinacion de pesticiddas organoclorados en aguas superficiales y subterraneas de la provincia de San Juan (Argentina)

    Energy Technology Data Exchange (ETDEWEB)

    Omar, B.; Suero, E.; Augusto, M.; Gimenez, M.; Flores, N.

    2003-07-01

    The level of contamination with organo chlorine pesticides and the occurrence of their degradation products in the basins of the two main rivers. San Juan and Jackal, of the Province of San Juan, Argentina, were determined. Surface and groundwater samples from both river basins were evaluated by capillary GC and results confirmed with Mass Spectrometry. Chemicals investigated were 16 organo chlorine pesticides. For a total number of 314 samples, the percentage of positive samples ranged from 68.6% for Heptachlor to 16% for Aldrin. concentration values and the percentage of positive samples in groundwater were significantly lower than those found in surface water. Samples taken in different seasons did not show significant differences. (Author) 18 refs.

  16. Implications of treating water containing polynuclear aromatic hydrocarbons with chlorine: a gas chromatographic-mass spectrometric study.

    OpenAIRE

    Oyler, A R; Liukkonen, R J; Lukasewycz, M K; Cox, D A; Peake, D A; Carlson, R M

    1982-01-01

    The products of aqueous chlorination reactions of 1-methylnaphthalene, fluorene, dibenzofuran, anthracene, phenanthrene, 1-methylphenanthrene, fluoranthene, and pyrene have been determined. The conditions employed for these reactions approximated those that might be encountered in water treatment facilities. Reactions at pH greater than 6 tended to produce oxygenated products (epoxides, phenols, quinones, etc.), and reactions at pH less than 6 tended to produce both oxygenated (quinones) and ...

  17. Effects of currently used pesticides and their mixtures on the function of thyroid hormone and aryl hydrocarbon receptor in cell culture.

    Science.gov (United States)

    Ghisari, Mandana; Long, Manhai; Tabbo, Agnese; Bonefeld-Jørgensen, Eva Cecilie

    2015-05-01

    Evidence suggest that exposure to pesticides can interfere with the endocrine system by multiple mechanisms. The endocrine disrupting potential of currently used pesticides in Denmark was analyzed as single compounds and in an equimolar mixture of 5 selected pesticides. The pesticides were previously analyzed for effects on the function of estrogen and androgen receptors, the aromatase enzyme and steroidogenesis in vitro. In this study, the effect on thyroid hormone (TH) function and aryl hydrocarbon receptor (AhR) transactivity was assessed using GH3 cell proliferation assay (T-screen) and AhR responsive luciferase reporter gene bioassay, respectively. Thirteen pesticides were analyzed as follows: 2-methyl-4-chlorophenoxyacetic acid, terbuthylazine, iodosulfuron-methyl-sodium, mesosulfuron-methyl, metsulfuron-methyl, chlormequat chloride, bitertanol, propiconazole, prothioconazole, mancozeb and its metabolite ethylene thiourea, cypermethrin, tau-fluvalinate, and malathion (currently banned in DK). In the T-screen, prothioconazole, malathion, tau-fluvalinate, cypermethrin, terbuthylazine and mancozeb significantly stimulated and bitertanol and propiconazole slightly reduced the GH3 cell proliferation. In the presence of triiodothyronine (T3), prothioconazole, tau-fluvalinate, propiconazole, cypermethrin and bitertanol significantly antagonized the T3-induced GH3 cell proliferation. Eleven of the tested pesticides agonized the AhR function, and bitertanol and prothioconazole inhibited the basal AhR activity. Bitertanol, propiconazole, prothioconazole and cypermethrin antagonized the TCDD-induced AhR transactivation at the highest tested concentration. The 5-component mixture had inducing effect but the combined effect could not be predicted due to the presence of bitertanol eliciting inhibitory effect. Upon removal of bitertanol from the mixture, the remaining four pesticides acted additively. In conclusion, our data suggest that pesticides currently used in Denmark

  18. ORGANOPHOSPHORUS PESTICIDE DEGRADATION PATHWAYS DURING DRINKING WATER TREATMENT

    Science.gov (United States)

    The objective of this work was to investigate organophosphorus (OP) pesticide transformation pathways as a class in the presence of aqueous chlorine. Seven priority OP pesticides were examined for their reactivity with aqueous chlorine: chlorpyrifos (CP), parathion (PA), diazino...

  19. Levels of Polycyclic Aromatic Hydrocarbons, Polychlorinated Biphenyls, and Organochlorine Pesticides in Various Tissues of White-Backed Vulture in India

    Directory of Open Access Journals (Sweden)

    V. Dhananjayan

    2013-01-01

    Full Text Available This study provides information on the current status of contamination by polycyclic aromatic hydrocarbons (PAHs, polychlorinated biphenyls (PCBs, and organochlorine pesticides (OCPs in the tissues of endangered White-backed Vulture Gyps bengalensis in India. Chemical analyses revealed detectable amounts of PAHs, PCBs, and OCPs. Concentration ranges of ∑PAHs, ∑PCBs, and ∑OCPs in tissues were 60–2037 ng/g, 30–5790 ng/g, and 3.2–5836 ng/g wet weight, respectively. 1,1-Dichloro-2,2-bis(p-chlorophenylethylene (p,p′-DDE concentrations ranged from below detectable level to 599 ng/g wet weight, representing more than 90% of the total dichlorodiphenyltrichloroethane (DDT. Among the various OCPs analyzed, p,p′-DDE was detected most frequently. All the contaminants recorded show higher accumulation in liver than other tissues. Levels of contaminants measured in the tissues of vulture are comparable with the levels documented in a number of avian species and are lower than those reported to have caused deleterious effects. Although no threat is expected from the current level of contamination, the presence of varying levels of contaminants and their additive or synergistic toxicity is a cause of concern to vultures. Values reported in this study can serve as guideline for future research.

  20. Chlorinated, brominated, and perfluorinated compounds, polycyclic aromatic hydrocarbons and trace elements in livers of sea otters from California, Washington, and Alaska (USA), and Kamchatka (Russia)

    Science.gov (United States)

    Kannan, K.; Moon, H.-B.; Yun, S.-H.; Agusa, T.; Thomas, N.J.; Tanabe, S.

    2008-01-01

    Concentrations of organochlorine pesticides (DDTs, HCHs, and chlordanes), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), polycyclic aromatic hydrocarbons (PAHs), perfluorinated compounds (PFCs), and 20 trace elements were determined in livers of 3- to 5-year old stranded sea otters collected from the coastal waters of California, Washington, and Alaska (USA) and from Kamchatka (Russia). Concentrations of organochlorine pesticides, PCBs, and PBDEs were high in sea otters collected from the California coast. Concentrations of DDTs were 10-fold higher in California sea otters than in otters from other locations; PCB concentrations were 5-fold higher, and PBDE concentrations were 2-fold higher, in California sea otters than in otters from other locations. Concentrations of PAHs were higher in sea otters from Prince William Sound than in sea otters from other locations. Concentrations of several trace elements were elevated in sea otters collected from California and Prince William Sound. Elevated concentrations of Mn and Zn in sea otters from California and Prince William Sound were indicative of oxidative stress-related injuries in these two populations. Concentrations of all of the target compounds, including trace elements, that were analyzed in sea otters from Kamchatka were lower than those found from the US coastal locations. ?? The Royal Society of Chemistry.

  1. Contamination profiles of selected PCB congeners, chlorinated pesticides, PCDD/Fs in Antarctic fur seal pups and penguin eggs.

    Science.gov (United States)

    Schiavone, Alessandra; Corsolini, Simonetta; Borghesi, Nicoletta; Focardi, Silvano

    2009-06-01

    The aim of this study was to investigate levels of some major environmental contaminants, such as polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and organochlorine pesticides in Antarctic samples. Concentrations of some persistent organic pollutants (POPs) were investigated in Antarctic fur seal pups and eggs of three species of penguins. Dichloro-diphenyl-trichloroethane (DDT) was the main pollutant, followed by PCBs; other organochlorine compounds such as hexachlorobenzene (HCB) and PCDD/Fs were usually found only in minor quantities. Adélie penguin eggs had significantly higher mean PCB concentrations (p0.05). TEQ values in fur seal blubber in our study were one order of magnitude lower than those considered to elicit physiological effects in aquatic mammals. In general, POP concentrations in our samples suggested that likely the study populations were not currently at risk for adverse health effects, but indicated a clear need for further monitoring to assess the presence and time trend of a broad range of contaminants, mainly emerging POPs thought to be increasing in polar regions.

  2. Residues of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides in organically-farmed vegetables.

    Science.gov (United States)

    Zohair, Azza; Salim, Abou-Bakr; Soyibo, Adeola A; Beck, Angus J

    2006-04-01

    The residues of polyaromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in soils from organic farms and their uptake by four varieties of organic-produced potatoes and three varieties of organic carrots from England were investigated. Samples of the soils, crop peels and cores were all Soxhlet-extracted in triplicate, cleaned up by open-column chromatography and analysed by a multi-residue analytical method using gas chromatography with mass selective detection. The concentrations of PAHs, PCBs and OCPs in soils from organic farms ranged from 590+/-43 to 2301+/-146 microg/kg, 3.56+/-0.73 to 9.61+/-1.98 microg/kg and 52.2+/-4.9 to 478+/-111 microg/kg, respectively. Uptake by different crop varieties were 8.42+/-0.93 to 40.1+/-4.9 microg/kg sigmaPAHs, 0.83+/-0.19 to 2.68+/-0.94 microg/kg sigmaPCBs and 8.09+/-0.83 to 133+/-27 microg/kg sigmaOCPs. Residue uptake from soils depended on plant variety; Desiree potato and Nairobi carrot varieties were more susceptible to PAH contamination. Likewise, uptake of PCBs and OCPs depended on potato variety. There were significant positive correlations between the PCB and OCP concentrations (Ppotatoes. Peeling carrots and potatoes was found to remove 52-100% of the contaminant residues depending on crop variety and the properties of the contaminants. Soil-crop bioconcentration factors (BCFs) decreased with increasing logK(ow) for PAHs up to about 4.5 and for PCBs up to about 6.5, above which no changes were discernible for either class of contaminants. No relationship was observed between soil-crop BCFs and logK(ow) for OCPs, most likely because their concentrations were low and variable. PMID:16297429

  3. Health Risk Assessment of Organic Chlorine Pesticides in the Waters of Weishan Lake%微山湖水域中有机氯农药健康风险评价

    Institute of Scientific and Technical Information of China (English)

    葛冬梅; 李美桃; 王波

    2014-01-01

    In order to do research on the potential risk of organic pollutants in Weishan Lake to human health in water ,this paper treats the water body ,sediments and organisms in the waters of Weishan Lake as the object of study .Based on the collection and ex-traction of organic chlorine pesticide content ,combining health risk assessment method ,and the non-carcinogenic risk index and car-cinogenic risk index is treated as the evaluation index of organic chlorine pesticides .The health risk assessment of organic chlorine pesticides in the waters of Weishan Lake is evaluated .The results show that :The non-carcinogenic risk index value of organic chlo-rine pesticides in the water is 0 .80 and is in the low level of risk .Carcinogenic risk index mean value is 1 .68 × 10-3 ,and is in a high level of risk .The non-carcinogenic risk index value of organic chlorine pesticides in sediments is 1 .88 × 10-5 ,carcinogenic risk index value is 3 .71 × 10-8 ,and both are in the acceptable risk range .The non-carcinogenic risk index of organic chlorine pesticides in or-ganisms is less than 10-4 ,and the non-carcinogenic risk is acceptable ,carcinogenic risk index is less than 10-5 ,and carcinogenic risk is also acceptable .%为研究微山湖水体中有机污染物对人体健康的潜在风险,以微山湖水域中水体、沉积物与生物体为研究对象,在采集和提取有机氯农药含量的基础上,结合健康风险评价方法,以有机氯农药的非致癌风险指数与致癌风险指数为评价指标,对微山湖水域中有机氯农药进行健康风险评价。结果表明:水体中有机氯农药的非致癌风险指数均值0.80,处于低风险水平;致癌风险指数均值为1.68×10-3,处于较高风险水平。沉积物中有机氯农药的非致癌风险指数均值为1.88×10-5,致癌风险指数均值为3.71×10-8,均处于可接受风险范围。生物体中有机氯农药的非致癌风险指数均小于10-4,认为

  4. Different behavioral effect dose–response profiles in mice exposed to two-carbon chlorinated hydrocarbons: Influence of structural and physical properties

    Energy Technology Data Exchange (ETDEWEB)

    Umezu, Toyoshi, E-mail: umechan2@nies.go.jp; Shibata, Yasuyuki, E-mail: yshibata@nies.go.jp

    2014-09-01

    The present study aimed to clarify whether dose–response profiles of acute behavioral effects of 1,2-dichloroethane (DCE), 1,1,1-trichloroethane (TCE), trichloroethylene (TRIC), and tetrachloroethylene (PERC) differ. A test battery involving 6 behavioral endpoints was applied to evaluate the effects of DCE, TCE, TRIC, and PERC in male ICR strain mice under the same experimental conditions. The behavioral effect dose–response profiles of these compounds differed. Regression analysis was used to evaluate the relationship between the dose–response profiles and structural and physical properties of the compounds. Dose–response profile differences correlated significantly with differences in specific structural and physical properties. These results suggest that differences in specific structural and physical properties of DCE, TCE, TRIC, and PERC are responsible for differences in behavioral effects that lead to a variety of dose–response profiles. - Highlights: • We examine effects of 4 chlorinated hydrocarbons on 6 behavioral endpoints in mice. • The behavioral effect dose–response profiles for the 4 compounds are different. • We utilize regression analysis to clarify probable causes of the different profiles. • The compound's physicochemical properties probably produce the different profiles.

  5. Low-concentration tailing and subsequent quicklime-enhanced remediation of volatile chlorinated hydrocarbon-contaminated soils by mechanical soil aeration.

    Science.gov (United States)

    Ma, Yan; Du, Xiaoming; Shi, Yi; Xu, Zhu; Fang, Jidun; Li, Zheng; Li, Fasheng

    2015-02-01

    Mechanical soil aeration has long been regarded as an effective ex-situ remediation technique and as suitable for remediation of large-scale sites contaminated by volatile organic compounds (VOCs) at low cost. However, it has been reported that the removal efficiency of VOCs from soil is relatively low in the late stages of remediation, in association with tailing. Tailing may extend the remediation time required; moreover, it typically results in the presence of contaminants residues at levels far exceeding regulations. In this context, the present study aimed to discuss the tailing that occurs during the process of remediation of soils contaminated artificially with volatile chlorinated hydrocarbons (VCHs) and to assess possible quicklime-enhanced removal mechanisms. The results revealed the following conclusions. First, temperature and aeration rate can be important controls on both the timing of appearance of tailing and the levels of residual contaminants. Furthermore, the addition of quicklime to soil during tailing can reduce the residual concentrations rapidly to below the remedial target values required for site remediation. Finally, mechanical soil aeration can be enhanced using quicklime, which can improve the volatilization of VCHs via increasing soil temperature, reducing soil moisture, and enhancing soil permeability. Our findings give a basic understanding to the elimination of the tailing in the application of mechanical soil aeration, particularly for VOCs-contaminated soils.

  6. Occurrence and availability of prioritary compounds (chlorinated pesticides, polybrominated diphenyl ethers, alkylphenols and heavy metals) in freshwater sediments and fish

    International Nuclear Information System (INIS)

    Full text: The aim of this work was to determine priority organic and inorganic compounds in river sediments and fish and to study their availability. Twelve organ chlorinated compounds (OC), 40 polybromodiphenyl ethers (PBDEs), 2 alkylphenols (nonylphenol and octylphenol) (AP), and 9 heavy metals (HM) were investigated in samples taken in 20 locations along the Ebro river, in north east Spain. Sediment samples represent a stable matrix which indicate recent pollution episodes, whereas fish samples are good sentinels to monitor bioavailability and bioaccumulation. Compound selection was based on their inclusion in European priority lists (Directives 76/464/CEE and 60/2000/EU). The study area covered the Ebro hydrographic basin which is the main tributary in Spain and flows through large agricultural areas characterized by wines, corn and maize and represents an important water source for the many industrial and urban activities settled along its course. To control the quality of the river basin, and in accordance with EU Directives, priority pollutants have been determined in sediment and fish to determine most ubiquitous compounds, geographical distribution and bioavailability of pollutants to two different fish species. For such purpose, different analytical methods were developed to analyse all the above mentioned chemical species in the upper 2 cm sediment layer and in whole fish (Barbus graellsii, Cyprinus carpio). Among compounds studied, hexachlorocyclohexane, pentachlorophenol, aldrin, dieldrin and isodrin, and trichlorobenzene were never detected. All samples contained organic pollutants at total levels between 134 and 3199 μg/Kg-dw and total HM from 60.9 and 5131 mg/kg-dw, depending on sample location. For 18 of the 20 samples points, a correlation of 0.53 was found between total organic and total inorganic concentration. In sediment samples, among the 4 chemical groups studied, HM were present at levels between 0.17 and 4036 mg/kg dry weight (dw), being

  7. Occurrence and availability of prioritary compounds (chlorinated pesticides, polybrominated diphenyl ethers, alkylphenols and heavy metals) in freshwater sediments and fish

    International Nuclear Information System (INIS)

    Full text: The aim of this work was to determine priority organic and inorganic compounds in river sediments and fish and to study their availability. Twelve organ chlorinated compounds (OC), 40 polybromodiphenyl ethers (PBDEs), 2 alkylphenols (nonylphenol and octylphenol) (AP), and 9 heavy metals (HM) were investigated in samples taken in 20 locations along the Ebro river, in north east Spain. Sediment samples represent a stable matrix which indicate recent pollution episodes, whereas fish samples are good sentinels to monitor bioavailability and bioaccumulation. Compound selection was based on their inclusion in European priority lists (Directives 76/464/CEE and 60/2000/EU). The study area covered the Ebro hydrographic basin which is the main tributary in Spain and flows through large agricultural areas characterized by wines, corn and maize and represents an important water source for the many industrial and urban activities settled along its course. To control the quality of the river basin, and in accordance with EU Directives, priority pollutants have been determined in sediment and fish to determine most ubiquitous compounds, geographical distribution and bioavailability of pollutants to two different fish species. For such purpose, different analytical methods were developed to analyse all the above mentioned chemical species in the upper 2 cm sediment layer and in whole fish (Barbus graellsii, Cyprinus carpio). Among compounds studied, hexachlorocyclohexane, pentachlorophenol, aldrin, dieldrin and isodrin, and trichlorobenzene were never detected. All samples contained organic pollutants at total levels between 134 and 3199 μg/Kg-dw and total HM from 60.9 and 5131 mg/kg-dw, depending on sample location. For 18 of the 20 samples points, a correlation of 0.53 was found between total organic and total inorganic concentration. In sediment samples, among the 4 chemical groups studied, HM were present at levels between 0.17 and 4036 mg/kg dry weight (dw), being

  8. Identification and quantification of known polycyclic aromatic hydrocarbons and pesticides in complex mixtures using fluorescence excitation-emission matrices and parallel factor analysis.

    Science.gov (United States)

    Ferretto, Nicolas; Tedetti, Marc; Guigue, Catherine; Mounier, Stéphane; Redon, Roland; Goutx, Madeleine

    2014-07-01

    Polycyclic aromatic hydrocarbons (PAHs) and pesticides are among the most widespread organic contaminants in aquatic environments. Because of their aromatic structure, PAHs and pesticides have intrinsic fluorescence properties in the ultraviolet/blue spectral range. In this study, excitation-emission matrix (EEM) fluorescence spectroscopy and parallel factor (PARAFAC) analysis were used to characterise and discriminate fluorescence signatures of nine PAHs and three pesticides at the μg L(-1) level in the presence of humic substances (0.1-10 mgCL(-1)). These contaminants displayed a diversity of fluorescence signatures regarding spectral position (λEx: 220-335 nm, λEm: 310-414 nm), Stokes shift (39-169 nm) and number of peaks (1-8), with detection limits ranging from 0.02 to 1.29μgL(-1). The EEM/PARAFAC method applied to mixtures of PAHs with humic substances validated a seven-component model that included one humic-like fluorophore and six PAH-like fluorophores. The EEM/PARAFAC method applied to mixtures of pesticides with humic substances validated a six-component model that included one humic-like fluorophore and three pesticide-like fluorophores. The EEM/PARAFAC method adequately quantified most of the contaminants for humic substance concentrations not exceeding 2.5 mg CL(-1). The application of this method to natural (marine) samples was demonstrated through (1) the match between the Ex and Em spectra of PARAFAC components and the Ex and Em spectra of standard PAHs, and (2) the good linear correlations between the fluorescence intensities of PARAFAC components and the PAH concentrations determined by GC-MS.

  9. Chlorinated and parent polycyclic aromatic hydrocarbons in environmental samples from an electronic waste recycling facility and a chemical industrial complex in China.

    Science.gov (United States)

    Ma, Jing; Horii, Yuichi; Cheng, Jinping; Wang, Wenhua; Wu, Qian; Ohura, Takeshi; Kannan, Kurunthachalam

    2009-02-01

    Chlorinated polycyclic aromatic hydrocarbons (CIPAHs) are a class of halogenated contaminants found in the urban atmosphere; they have toxic potential similar to that of dioxins. Information on the sources of CIPAHs is limited. In this study, concentrations of 20 CIPAHs and 16 parent PAHs were measured in electronic wastes, workshop-floor dust, vegetation, and surface soil collected from the vicinity of an electronic waste (e-waste) recycling facility and in surface soil from a chemical industrial complex (comprising a coke-oven plant, a coal-fired power plant, and a chlor-alkali plant), and agricultural areas in central and eastern China. High concentrations of SigmaCIPAHs were found in floor dust (mean, 103 ng/g dry wt), followed in order of decreasing concentration by leaves (87.5 ng/g drywt), electronic shredder waste (59.1 ng/g dry wt), and soil (26.8 ng/g dry wt) from an e-waste recycling facility in Taizhou. The mean concentration of SigmaCIPAHs in soil from the chemical industrial complex (88 ng/g dry wt) was approximately 3-fold higher than the concentration in soil from e-waste recycling facilities. The soils from e-waste sites and industrial areas contained mean concentrations of SigmaCIPAHs 2 to 3 orders of magnitude higher than the concentrations in agricultural soils (ND-0.76 ng/g), suggesting that e-waste recycling and chlorine-chemical industries are potential emission sources of CIPAHs. The profiles of CIPAHs in soil and dust were similar to a profile that has been reported previously for fly ash from municipal solid waste incinerators (6-CIBaP was the predominant compound), but the profiles in vegetation and electronic shredder waste were different from those found in fly ash. Concentrations of 16 parent PAHs were high (150-49,700 ng/g) in samples collected from the e-waste recycling facility. Significant correlation between SigmaCIPAH and SigmaPAH concentrations suggests that direct chlorination of parent PAHs is the major pathway of formation of

  10. Site profiles of low-volatile chlorinated hydrocarbons - cause-oriented monitoring in aquatic media. Vol.2. Low-volatile chlorinated hydrocarbons in surface water, sediments, suspended matter and fish of the Elbe river and its tributaries; Standortprofile schwerfluechtiger chlorierter Kohlenwasserstoffe (SCKW) - ursachenorientiertes Monitoring in aquatischen Medien. Bd. 2. SCKW in Oberflaechenwasser, Sediment, Schwebstoffen und Fischen aus der Elbe und Nebenfluessen

    Energy Technology Data Exchange (ETDEWEB)

    Heinisch, E.; Kettrup, A.; Gebefuegi, I.; Martens, D.; Bergheim, W.; Wenzel, S.

    2001-07-01

    Evaluating the primary data from ARGE ELBE, LAU Halle/Saale and the Environmental Specimen Banking (Umweltprobenbank) as well from publications from the Czech Republic (CHMU) the concentrations of the following low volatile chlorinated hydrocarbons were established for surface water, sediment, breams and eels from the rivers Elbe, Schwarze Elster, Mulde and Saale partly from 1989 till 1999: DDT and its metabolites DDE and DDD, partly as 2,4'- and 4,4' isomers; HCH ({alpha}-, {beta}-, {gamma}- and {delta} isomers); chlorinated benzenes with 1-6 Cl atoms and octachlorostyrene. The data evaluated were drawn up into tables - comprehensive in a separate supplement, in short versions within the text - and consolidated into graphs. Aim of the paper was a cause-oriented monitoring. The by far most important emission sources, found from the distance and time profiles as well as from special assessments of the substance patterns, were chemical plants. (orig.) [German] Durch Auswertung von Primaerdaten der ARGE ELBE, des LAU Halle/Saale und der Umweltprobenbank sowie von Publikationen aus Tschechien (CHMU) wurden fuer Oberflaechenwasser, Sediment, Brassen/Bleien und Aale aus der Elbe, Schwarzen Elster, Mulde und Saale fuer die Jahre von z.T. 1989 bis 1999 die Konzentrationen der folgenden schwerfluechtigen Kohlenwasserstoffe (SCKW) ermittelt: DDT und seine Metabolite DDE und DDD, z.T. als 2,4'- und 4,4'-Isomere; HCH ({alpha}-, {beta}-, {gamma}- und {delta}-Isomere); chlorierte Benzole mit 1-6 Cl-Atomen und Octachlorstyrol. Die ausgewerteten Daten wurden zu Tabellen - ausfuehrlich in einem gesonderten Tabellenanhang und verkuerzt im Textteil - zusammengestellt sowie zu Grafiken verdichtet. Ziel der Arbeit war ein ursachenorientiertes Monitoring. Als mit Abstand wesentlichste Emissionsquellen konnten anhand von Streckenprofilen und Zeitrastern sowie durch spezielle Auswertungen der Stoffmusterverteilungen Chemibetriebe ermittelt werden. (orig.)

  11. Bioremediation of soils contaminated with polycyclic aromatic hydrocarbons, petroleum, pesticides, chlorophenols and heavy metals by composting: Applications, microbes and future research needs.

    Science.gov (United States)

    Chen, Ming; Xu, Piao; Zeng, Guangming; Yang, Chunping; Huang, Danlian; Zhang, Jiachao

    2015-11-01

    Increasing soil pollution problems have caused world-wide concerns. Large numbers of contaminants such as polycyclic aromatic hydrocarbons (PAHs), petroleum and related products, pesticides, chlorophenols and heavy metals enter the soil, posing a huge threat to human health and natural ecosystem. Chemical and physical technologies for soil remediation are either incompetent or too costly. Composting or compost addition can simultaneously increase soil organic matter content and soil fertility besides bioremediation, and thus is believed to be one of the most cost-effective methods for soil remediation. This paper reviews the application of composting/compost for soil bioremediation, and further provides a critical view on the effects of this technology on microbial aspects in contaminated soils. This review also discusses the future research needs for contaminated soils. PMID:26008965

  12. Bioremediation of soils contaminated with polycyclic aromatic hydrocarbons, petroleum, pesticides, chlorophenols and heavy metals by composting: Applications, microbes and future research needs.

    Science.gov (United States)

    Chen, Ming; Xu, Piao; Zeng, Guangming; Yang, Chunping; Huang, Danlian; Zhang, Jiachao

    2015-11-01

    Increasing soil pollution problems have caused world-wide concerns. Large numbers of contaminants such as polycyclic aromatic hydrocarbons (PAHs), petroleum and related products, pesticides, chlorophenols and heavy metals enter the soil, posing a huge threat to human health and natural ecosystem. Chemical and physical technologies for soil remediation are either incompetent or too costly. Composting or compost addition can simultaneously increase soil organic matter content and soil fertility besides bioremediation, and thus is believed to be one of the most cost-effective methods for soil remediation. This paper reviews the application of composting/compost for soil bioremediation, and further provides a critical view on the effects of this technology on microbial aspects in contaminated soils. This review also discusses the future research needs for contaminated soils.

  13. The effects of rice canopy on the air-soil exchange of polycyclic aromatic hydrocarbons and organochlorine pesticides using paired passive air samplers.

    Science.gov (United States)

    Wang, Yan; Wang, Shaorui; Luo, Chunling; Li, Jun; Ming, Lili; Zhang, Gan; Li, Xiangdong

    2015-05-01

    The rice canopy in paddy fields can influence the air-soil exchange of organic chemicals. We used paired passive air samplers to assess the exchange of polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) in a paddy field, South China. Levels of OCPs and light PAHs were generally higher under the canopy than above it. We found that the rice canopy can physically obstruct the evaporation of most OCPs and light PAHs, and can also act as a barrier to the gaseous deposition of p,p'-DDT and heavy PAHs. Paddy fields can behave as a secondary source of OCPs and light PAHs. The homolog patterns of these two types of chemical varied slightly between the air below and above the rice canopy, implying contributions of different sources. Paired passive air samplers can be used effectively to assess the in situ air-soil exchange of PAHs and OCPs in subtropical paddy fields. PMID:25686886

  14. Correlation between maternal milk and infant serum levels of chlorinated pesticides (CP) and the impact of elevated CP on bleeding tendency and immune status in some infants in Egypt.

    Science.gov (United States)

    Schaalan, Mona F; Abdelraouf, Sahar M; Mohamed, Waleed A; Hassanein, Fetouh S

    2012-01-01

    Chlorinated pesticides (CP) are environmentally persistent pollutants that (prenatally through the placenta and post-natally via breastfeeding) are transferred from mother to child. Considering the significant bleeding tendency noted in infants of CP-intoxicated mothers in Egypt, this study aimed to investigate any correlation between levels of these xenobiotics in mothers' milk and bleeding tendencies of their infants, as well as a possible role of any related immunosuppression in this phenomenon. This study examined 180 newborns presenting with altered bleeding tendencies and their mothers, and 180 normal newborns and their mothers (serving as a controls), selected from the Breastfeeding Unit, Center for Social and Preventive Medicine at the Cairo University Pediatric Hospital. Chlorinated pesticides (e.g., hexachlorocyclohexane, DDT, hepta-chloroepoxide, α- and β-endosulfan, aldrin, endrin, dieldrin) levels and their derivatives were measured in mothers' milk as well as in serum of neonates using gas chromatography/high resolution mass spectrometry. To link bleeding tendency with lactational intoxication of neonates by CP, newborns' blood was assessed for: platelet count, bleeding and prothrombin time, liver enzymes, Vitamin K, TNFα, and IL-10. Breast milk CP levels were associated with a higher incidence of bleeding in infants. Interference with the coagulation cascade was supported by changes in prothrombin time (prolonged), platelet counts (decreased), liver enzymes (increased), and serum vitamin K concentrations (decreased). Moreover, the significant decrease in WBC count and lymphocytes added to depressed cytokine secretion, i.e., TNFα and IL-10, suggested an organochlorine-induced immunotoxicity in infants developmentally exposed to the agents. We conclude that maternal transfer of CP, via breastfeeding or across the placenta, was sufficient to achieve similar CP levels in the serum of their infants; this correlated with a manifesting of altered

  15. Estimation of measurement uncertainty of pesticides, polychlorinated biphenyls and polyaromatic hydrocarbons in sediments by using gas chromatography-mass spectrometry.

    Science.gov (United States)

    Pindado Jiménez, Oscar; Pérez Pastor, Rosa Ma

    2012-04-29

    The evaluation of the uncertainty associated to analytical methods is essential in order to demonstrate quality of a result. However, there is often lack of information about uncertainty of methods to estimate persistent organic pollutants concentration in complex matrix. Current work has thoroughly evaluated uncertainty associated to quantification of several organochloride pesticides, PCBs and PAHs in sediments. A discussion of the main contributions to the overall uncertainty is reported, allowing authors to establish the accuracy of results and plan future improvements. Combined uncertainties ranged between 5-9% (pesticides), 4-7% (PCBs) and 5-10% (PAHs), being uncertainty derived of calibration the main contribution. Also, the analytical procedure was validated analysing a standard reference material (IAEA-408).

  16. CONTINUOUS-MODE PHOTOCATALYTIC DEGRADATION OF CHLORINATED PHENOLS AND PESTICIDES IN WATER USING A BENCH-SCALE TIO2 ROTATING DISK REACTOR

    Science.gov (United States)

    Photocatalytic degradation of phenol, chlorinated phenols, and lindane was evaluated in a continuous flow TiOz rotating disk photocatalytic reactor (RDPR). The RDPR operated at a hydraulic residence time of 0.25 day and at a disk angular velocity of 12 rpm. At low molar feed conc...

  17. 环境监测用5种氯代烯烃混合气体标准样品研制%Development of a Standard Reference Material Containing 5 Chlorinated Hydrocarbons for Environmental Monitoring

    Institute of Scientific and Technical Information of China (English)

    李宁; 范洁; 王倩; 樊强

    2014-01-01

    The development of reference material of the mixed gas of five hydrochloric hydrocarbons was described. Vinyl chloride is gas, 1, 1-Dichloroethylene cis-1,2-Dichloroethene, Trichloroethylene, Trichloroethylene, Tetrachloroethylene are liquid at room temperature, and so it is difficult to prepare an accurate a standard Reference Material containing 5 Chlorinated hydrocarbons. This research adopts two-step weighting method to prepare the standard gas of five hydrochloric hydrocarbons, and the relative standard deviation of preparation repeatability is less than 1�6%. The experimental method of within-bottle homogeneity of 5 chlorinated hydrocarbon gas standards was developed, and whether the trend for the values varying with the sample pressure changed was used to investigate the sample homogeneity. Based on experimental results, 5 volatile chlorinated hydrocarbons standard gas is homogeneous, and the minimum pressure was determined as 1MPa. The experiment design and data evaluation of long-stability is according to ISO Guide 35 ( Reference materials-General and statistical principles for certification) . Individual Sample was measured as time elapses over a period of 12 months under identical conditions. The analytical data showed no instability was observed and all 5 chlorinated hydrocarbons in treated aluminum gas cylinders was stable for as long as 12 months. The relative expanded uncertainty is 3%( confidence coefficient is 95%) .%介绍了1μmol/mol氮气中5种氯代烯气体标准样品的研制方法。这5种氯代烯包括氯乙烯、1,1-二氯乙烯、顺1,2-二氯乙烯、三氯乙烯、四氯乙烯,其中氯乙烯常温下为气态,其他4种为液态,并且沸点低,将这几种氯代烯制备成气体标准样品存在制备精度低、气液转换不完全等困难。经研究,采用2步称量法制备5种氯代烯气体标准样品,重复制备的相对标准偏差小于1�6%。建立了5种氯代烯标准气体瓶内均匀性

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

    Science.gov (United States)

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

    2010-01-01

    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

  19. Poisoning of animals in the Los Angeles area with pesticides during 1977.

    Science.gov (United States)

    Maddy, K T; Winter, J

    1980-12-01

    During 1977, there were 289 pesticide exposure incidents involving animals that were handled by the Thomas J. Fleming Memorial Poison Information Center in Los Angeles. Almost all of this service was provided to veterinarians and most of the incidents involved dogs. Cases handled by this center are considered typical for small animal practices in urban areas of California. Ingestion was the major route of exposure. As recently as 10 years ago, arsenic, strychnine, and phosphorus were major causes of such poisonings. During 1977, the n-methylcarbamates (27%), anticoagulants (19%), and organo-phosphates (15%) were the major pesticides involved in exposure incidents. Lesser percentages of cases attributed to a specific chemical included: Vacor (5%), metaldehyde (4%), chlorinated hydrocarbons (4%), and arsenicals (4%). A variety of other pesticides, classified as miscellaneous, were also involved in poisonings to a lesser extent.

  20. The potential effects of phytoplankton on the occurrence of organochlorine pesticides (OCPs) and polycyclic aromatic hydrocarbons (PAHs) in water from Lake Taihu, China.

    Science.gov (United States)

    Zhao, Zhonghua; Zhang, Lu; Deng, Jianming; Wu, Jinglu

    2015-06-01

    Seasonal distribution of organochlorine pesticides (OCPs) and polycyclic aromatic hydrocarbons (PAHs) and their possible interactions with phytoplankton species in water from Lake Taihu were investigated. OCP concentrations ranged from 69.95 to 223.08 ng L(-1) in winter and from 80.95 to 376.03 ng L(-1) in summer, while PAHs ranged from 45.40 to 232.74 ng L(-1) in winter and 49.53 to 197.72 ng L(-1) in summer. Such physicochemical and biological parameters as the larger amounts of pollutants taken up by phytoplankton, the increased atmospheric wet deposition, the discharge of wastewater, and the resuspension of polluted sediments in summer time were responsible for the higher residues of both OCPs and PAHs than in winter. Canonical correspondence analysis (CCA) between phytoplankton biomass and micropollutants indicated high affinity of OCPs to Bacillariophyta and Cryptophyta and PAHs to Cyanophyta and Chlorophyta, documenting the ecological effects of phytoplankton on the biogeochemical processes of OCPs and PAHs and thus should be further investigated especially in hyper-eutrophic lakes. PMID:25968073

  1. Wintertime size distribution of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in the urban environment: Street- vs rooftop-level measurements

    Science.gov (United States)

    Chrysikou, Loukia P.; Gemenetzis, Panagiotis G.; Samara, Constantini A.

    The size distribution of ambient air particles and associated organic pollutants, such as polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs) including hexachlorocyclohexanes (HCHs), DDT and metabolites, etc., was investigated at a traffic-impacted site of Thessaloniki, Greece. Investigation took place during wintertime of 2006 at two heights above ground: at the street level (1.5 m) and at the rooftop level (15 m). Size-resolved samples (7.5 μm) were concurrently collected from the two height levels using five-stage high volume cascade impactors. At both heights, particle mass exhibited bimodal distribution with peaks in the 0.95-1.5 μm and the 3-7.5 μm size fractions, whereas most organic pollutants exhibited one peak at 0.95-1.5 μm. Apart from the 0.95-1.5 μm fraction, particle concentrations of all size ranges were significantly higher at the street level than at the rooftop as a result of more intensive vehicular emissions and road dust resuspension. On the contrary, the concentrations of most organic pollutants did not differentiate significantly between the two elevations.

  2. Comment on 'inflow, levels and the fate of some persistent chlorinated hydrocarbons in the Rijeka Bay area of the Adriatic Sea by N. Picer and M. Picer'

    Digital Repository Service at National Institute of Oceanography (India)

    Sarkar, A.

    highlighted in more detail and more specific with regard to the use of the reagent. (5) It is mentioned that the separation of PCBs from chlorinated insecticides was performed on a miniature silica gel column (Picer and Ahel, 1978). Such a statement does... is needed in order to justify the resolution of the peaks for identification of organochlorine compounds and their quantification. 733 734 Comment Moreover, they have contradicted themselves by employing a range of correction factors from 1.4 to 2...

  3. Characterization of Preferential Ground-Water Seepage From a Chlorinated Hydrocarbon-Contaminated Aquifer to West Branch Canal Creek, Aberdeen Proving Ground, Maryland, 2002-04

    Science.gov (United States)

    Majcher, Emily H.; Phelan, Daniel J.; Lorah, Michelle M.; McGinty, Angela L.

    2007-01-01

    Wetlands act as natural transition zones between ground water and surface water, characterized by the complex interdependency of hydrology, chemical and physical properties, and biotic effects. Although field and laboratory demonstrations have shown efficient natural attenuation processes in the non-seep wetland areas and stream bottom sediments of West Branch Canal Creek, chlorinated volatile organic compounds are present in a freshwater tidal creek at Aberdeen Proving Ground, Maryland. Volatile organic compound concentrations in surface water indicate that in some areas of the wetland, preferential flow paths or seeps allow transport of organic compounds from the contaminated sand aquifer to the overlying surface water without undergoing natural attenuation. From 2002 through 2004, the U.S. Geological Survey, in cooperation with the Environmental Conservation and Restoration Division of the U.S. Army Garrison, Aberdeen Proving Ground, characterized preferential ground-water seepage as part of an ongoing investigation of contaminant distribution and natural attenuation processes in wetlands at this site. Seep areas were discrete and spatially consistent during thermal infrared surveys in 2002, 2003, and 2004 throughout West Branch Canal Creek wetlands. In these seep areas, temperature measurements in shallow pore water and sediment more closely resembled those in ground water than those in nearby surface water. Generally, pore water in seep areas contaminated with chlorinated volatile organic compounds had lower methane and greater volatile organic compound concentrations than pore water in non-seep wetland sediments. The volatile organic compounds detected in shallow pore water in seeps were spatially similar to the dominant volatile organic compounds in the underlying Canal Creek aquifer, with both parent and anaerobic daughter compounds detected. Seep locations characterized as focused seeps contained the highest concentrations of chlorinated parent compounds

  4. Comparison of the uptake of polycyclic aromatic hydrocarbons and organochlorine pesticides by semipermeable membrane devices and caged fish (Carassius carassius) in Taihu Lake, China

    Science.gov (United States)

    Ke, R.; Xu, Y.; Huang, S.; Wang, Z.; Huckins, J.N.

    2007-01-01

    Uptake of polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) by triolein-containing semipermeable membrane devices (SPMDs) and by crucian carp (Carassius carassius) was studied in Taihu Lake, a shallow, freshwater lake in China. Crucian carp and SPMDs were deployed side by side for 32 d. The first-order uptake rate constants of individual PAHs and OCPs for the two matrices were calculated and compared to relate the amounts of chemicals accumulated by the matrices to dissolved water concentrations. On a wet-weight basis, total concentrations of PAHs and OCPs in crucian carp fillets averaged 49.5 and 13.6 ng/g, respectively, after the 32-d exposure, whereas concentrations in whole SPMDs averaged 716.9 and 62.3 ng/g, respectively. The uptake rate constants of PAHs and OCPs by SPMDs averaged seven- and fivefold higher, respectively, than those for crucian carp; however, the patterns of uptake rate constants derived from test chemical concentrations in the crucian carp and SPMDs were similar. Although equilibrium was not reached for some PAHs and OCPs during the 32-d exposure period, a reasonably good correlation between the concentration factors (CFs) and octanol/water partition coefficient (K ow) values of PAHs and OCPs in SPMDs (r = 0.86, p < 0.001) was observed when potential sorption to dissolved organic carbon was taken into account. Similar efforts to correlate the CFs and Kow values of PAHs and OCPs in crucian carp (r = 0.75, p < 0.001) were less successful, likely because of PAH metabolism by finfish. Overall, the present results suggest that SPMDs may serve as a surrogate for contaminant monitoring with fish in freshwater lake environments. ?? 2007 SETAC.

  5. 污水处理过程中苯系物和氯代烃三相分布规律%Distributions of BTEX and Chlorinated Hydrocarbons in Three Phases During Wastewater Treatment Processing

    Institute of Scientific and Technical Information of China (English)

    王琨; 杨俊晨; 黄丽坤; 高娜; 赵庆良

    2012-01-01

    为研究污水处理过程中曝气对苯系物中苯、甲苯和二甲苯以及氯代烃中三氯甲烷、四氯化碳、三氯乙烯和四氯乙烯去除的影响,设计了2个反应器,模拟污水处理过程,一个为活性污泥反应器,另一个为没有活性污泥的对照反应器.结果表明,在液相中,30.6%的TOC未经微生物降解而直接因曝气逸散到气相.苯系物的逸散比例达到了100%;三氯甲烷、四氯化碳、三氯乙烯和四氯乙烯的逸散比例分别为27.5%、39.0%、42.4%和38.5%.同时利用密闭水箱研究了生物处理单元中苯系物和氯代烃三相分布规律.在厌氧阶段,固相中苯、甲苯、二甲苯、三氯甲烷、四氯化碳、三氯乙烯和四氯乙烯占总量比例分别为38.7%、43.6%、38.0%、28.8%、24.3%、15.3%和20.5%.在曝气阶段,苯系物全部被去除,氯代烃总量略有下降.二沉池阶段,固相中三氯甲烷、四氯化碳、三氯乙烯、四氯乙烯占总质量的比例分别为5.2%、20.1%、6.8%和0%.%In order to investigate the influence of aeration on removal of BTEX ( benzene, toluene, xylene) and chlorinated hydrocarbons ( chloroform, carbon tetrachloride, trichloroethylene, tetrachloroethylene) during wastewater treatment processing, two lab-scale parallel reactors with and without activated sludge were designed to simulate wastewater treatment processing. The results indicated that 30. 6% of TOC in the liquid phase volatilized during aeration without microbial decomposition. The volatilization ratio of BTEX reached 100% , and the ratios of chloroform, carbon tetrachloride, trichloroethylene and tetrachloroethylene were 27.5% , 39.0% , 42.4% and 38.5% , respectively. At the same time, a dedicated tank was used to study the distribution of BTEX and chlorinated hydrocarbons in the three phases. Under the anaerobic condition, the percentages of benzene, toluene, xylene, chloroform, carbon tetrachloride, trichloroethylene

  6. Comparison of aliphatic hydrocarbons, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, polybrominated diphenylethers, and organochlorine pesticides in Pacific sanddab (Citharichthys sordidus) from offshore oil platforms and natural reefs along the California coast

    Science.gov (United States)

    Gale, Robert W.; Tanner, Michael J.; Love, Milton S.; Nishimoto, Mary M.; Schroeder, Donna M.

    2013-01-01

    Recently, the relative exposure of Pacific sanddab (Citharichthys sordidus) to polycyclic aromatic hydrocarbons (PAHs) at oil-production platforms was reported, indicating negligible exposure to PAHs and no discernible differences between exposures at platforms and nearby natural areas sites. In this report, the potential for chronic PAH exposure in fish is reported, by measurement of recalcitrant, higher molecular weight PAHs in tissues of fish previously investigated for PAH metabolites in bile. A total of 34 PAHs (20 PAHs, 11 alkylated PAHs, and 3 polycyclic aromatic thiophenes) were targeted. In addition, legacy contaminants—polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs),—and current contaminants, polybrominated diphenylethers (PBDEs) linked to endocrine disruption, were measured by gas chromatography with electron-capture or mass spectrometric detection, to form a more complete picture of the contaminant-related status of fishes at oil production platforms in the Southern California Bight. No hydrocarbon profiles or unresolved complex hydrocarbon background were found in fish from platforms and from natural areas, and concentrations of aliphatics were low less than 100 nanograms per gram (ng/g) per component]. Total-PAH concentrations in fish ranged from 15 to 37 ng/g at natural areas and from 8.7 to 22 ng/g at platforms. Profiles of PAHs were similar at all natural and platform sites, consisting mainly of naphthalene and methylnaphthalenes, phenanthrene, fluoranthene, and pyrene. Total-PCB concentrations (excluding non-ortho-chloro-substituted congeners) in fish were low, ranging from 7 to 22 ng/g at natural areas and from 10 to 35 ng/g at platforms. About 50 percent of the total-PCBs at all sites consisted of 11 congeners: 153 > 138/163/164 > 110 > 118 > 15 > 99 > 187 > 149 > 180. Most OCPs, except dichlorodiphenyltrichloroethane (DDT)-related compounds, were not detectable or were at concentrations of less than 1 ng/g in fish. p

  7. Risk assessment of organic chlorine pesticides in sinonovacula constricta from Ningbo coastal waters%宁波近岸海域缢蛏有机氯农药风险评估

    Institute of Scientific and Technical Information of China (English)

    徐国锋; 魏天飞; 郭清荣; 唐德富

    2015-01-01

    In order to study the effect of organic chlorine pesticides contamination of the razor clam,sinonovacula constricta,for food safety,11 samples from different sites were collected along the coast of Ningbo in 2010,and the contents of organic chlorinated pesticides consisting of 8 monomers were detected by a gas chromatography with e-lectron capture detector.The exposure risk index and carcinogenic risk index are used for the risk assessment and the safety consumption.As the maximum residue limits for pesticides and marine biological quality only limited the total value of HCHs and DDTs,which didn't limit the monomer value of HCHs and DDTs in China's regulation,this report used Australia food standard code for the monomer value evaluation of HCHs and DDTs.The results showed that the residues of α-HCH,β-HCH,γ-HCH,pp′-DDE,pp′-DDD,pp′-DDT are below the limit quantity of food sanitation of Australia and the total value of HCHs and DDTs meet with the first class of Marine Biological Quality of China.The carcinogenic risk index(CRI)is 1.61 ×10 -5 ~9.98 ×10 -5 ,and the exposure risk index(ERI)is 0.00 ~2.55 ×10 -2 .It is suggested that the safe consumption of the edible part of the clam by one kilogram body weight per person each day is averaged 0.044 kg according to acceptable carcinogenic risk index (CRI≤ 1 × 10 -4 ),or 0.502 kg according to acceptable exposure risk index (ERI≤1 ).The harm of organic chlorine pesti-cides for consumers who use the clam from coastal Ningbo is a minimal probability.%为了探讨有机氯农药对缢蛏的食用安全性影响,2010年在宁波近岸海域采集了11个缢蛏样品用气相色谱法测定其持久性有机氯农药(8种)的残留量,采用接触风险指数法及致癌风险指数法进行了风险评估以及安全消费量的估算.由于我国《食品中农药最大残留限量标准》和《海洋生物质量》中只对 HCHs 和 DDTs 总量进行限值,未对各分量进行具体限值,采

  8. Polychlorinated biphenyls and chlorinated pesticides in king mackerel caught off the coast of Pernambuco, northeastern Brazil: Occurrence, contaminant profile, biological parameters and human intake.

    Science.gov (United States)

    Miranda, Daniele A; Yogui, Gilvan T

    2016-11-01

    Persistent organic pollutants such as PCBs and DDTs are ubiquitous worldwide. Their lipophilic nature facilitates accumulation in fish tissues. This study investigated 182 PCB congeners and 14 organochlorine pesticides (DDTs, HCHs, chlordanes, heptachlor and mirex) in muscle and liver of king mackerel (Scomberomorus cavalla) caught off the northeastern coast of Brazil. Concentration of PCBs, DDTs and chlordanes in muscle averaged 31.5, 4.70 and 0.15ngg(-1) dry weight (dw), respectively. Mean levels of the same contaminants in liver were 145, 18.7 and 1.11ngg(-1) dw, respectively. HCHs, heptachlor and mirex were not detected in the samples. The metabolite p,p'-DDE dominated the composition of DDTs in both muscle and liver. However, a clear shift was observed in the proportions of p,p'-DDT and p,p'-DDD when comparing both tissues, suggesting metabolism in the liver. The PCBs profile revealed a depletion in mono- through tetra-CBs and an enrichment in penta- through deca-CBs. Biological parameters such as sex, maturity stage, age, body weight and total length did not influence contaminant levels in tissues. Dietary risk assessment indicated that S. cavalla from the northeastern coast of Brazil does not pose a health risk for humans. PMID:27392580

  9. 挥发性氯代烃在土壤中的吸附行为研究进展%A REVIEW OF STUDIES ON SORPTION BEHAVIORS OF VOLATILE CHLORINATED HYDROCARBONS IN NATURAL SOIL

    Institute of Scientific and Technical Information of China (English)

    刘锐; 孟凡勇; 文晓刚; 陈吕军; 张永明

    2012-01-01

    挥发性氯代烃(Volatile chlorinated hydrocarbons,VCHs)是工业污染场地的常见污染物,在非饱和带存在于土壤气相、水相、固相或以高密度非水相液体(Dense non-aqueous phase liquids,DNAPL)的形式存在,形成一个动态平衡系统.土壤对VCHs的吸附不仅影响土壤中的污染物浓度,而且极大地影响VCHs的迁移转化行为.根据VCHs在土壤中的吸附机制,可以对土壤中的VCHs浓度进行预测,优化各种模型参数,指导污染修复及管理工作.本文总结了VCHs在非饱和带土壤中的相间分配特征,吸附机制及其影响因素,特别探讨了土壤有机碳、矿物及水分对吸附的影响,提出了当前研究中存在的问题,并对将来研究进行了展望.%Volatile chlorinated hydrocarbons (VCHs) are common pollutants in industrial polluted sites, existing in aqueous phase, gaseous phase, solid phase or the form of dense non-aqueous phase liquids ( DNAPL) , in unsaturated zones of the soil, forming a dynamic equilibrium system. The sorption of VCHs by the soil not only influences concentration of the pollutants in the soil, but also affects substantially migration and fate of VCHs. Understanding the mechanisms of VCHs sorption by the soil may help predict their concentrations in the soil, optimize the parameters of pertinent models, and guide remediation and management of the contaminated soil. A review is presented to summarize characteristics of the distribution of VCHs between these phases in soils of unsaturated zones, their sorption mechanisms as well as their affecting factors, and to elaborate in particular influences of soil organic carbon, minerals, and soil water on their sorption. Meanwhile, existent problems are pointed out in the current researches and an outlook is described of the future researches.

  10. Temporal and spatial variabilities of atmospheric polychlorinated biphenyls (PCBs), organochlorine (OC) pesticides and polycyclic aromatic hydrocarbons (PAHs) in the Canadian Arctic: results from a decade of monitoring.

    Science.gov (United States)

    Hung, H; Blanchard, P; Halsall, C J; Bidleman, T F; Stern, G A; Fellin, P; Muir, D C G; Barrie, L A; Jantunen, L M; Helm, P A; Ma, J; Konoplev, A

    2005-04-15

    The Northern Contaminants Program (NCP) baseline monitoring project was established in 1992 to monitor for persistent organic pollutants (POPs) in Arctic air. Under this project, weekly samples of air were collected at four Canadian and two Russian arctic sites, namely Alert, Nunavut; Tagish, Yukon; Little Fox Lake, Yukon; Kinngait, Nunavut; Dunai Island, Russia and Amderma, Russia. Selected POPs, including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine (OC) pesticides, were analyzed in both the gas and particulate phases. This paper summarizes results obtained from this project in the past 5 years. Temporal trends were developed for atmospheric PCBs and OCs observed at Alert using a digital filtration (DF) technique. It was found that trends developed with 5 years of data (1993-1997) did not differ significantly from those determined with 7 years of data (1993-1999). This implies that with the DF technique, long-term trends can still be developed with less than 10 years of data. An acceleration in decline of OC and PCB air concentrations was noted in 1999 for some compounds, although the reason is unknown. Monitoring efforts must continue to assess the effect of this decline on the long-term trends of POPs in the Canadian Arctic. Occasional high trans-/cis-chlordane ratios and heptachlor air concentrations measured at Alert between 1995 and 1997 suggests sporadic fresh usage of chlordane-based pesticides. However, significant decreasing trends of chlordanes along with their chemical signatures has provided evidence that emission of old soil residues is replacing new usage as an important source to the atmosphere. Measurements of OC air concentrations conducted at Kinngait in 1994-1995 and 2000-2001 indicated faster OC removal at this location than at Alert. This may be attributed to the proximity of Kinngait to temperate regions where both biotic and abiotic degradation rates are faster. The PAH concentrations observed

  11. 水中氯代烃单体碳同位素分析中预富集方法进展%Review on Pre-enrichment Methods in Compound Specific Carbon Isotope Analysis of Chlorinated Hydrocarbon in Water

    Institute of Scientific and Technical Information of China (English)

    凌媛; 黄毅; 尚文郁; 谢曼曼; 刘舒波; 孙青

    2011-01-01

    Highly accurate determination of Compound Specific Carbon Isotope Analysis ( CSIA ) of chlorinated hydrocarbons is of great significance in tracing the source and revealing the biodegradating progress of pollutants. The isotopic composition of organic contaminations may be stable or varied in the process of environmental transformation. We can trace the source of contaminations if the composition is stable and can evaluate the probability and degree of degradation of contaminations. This paper summarizes solid-phase microextraction, static headspace analysis, purge and trap method and compound specific isotope analyses of chlorinated hydrocarbon in water, using combinations of these pretreatment methods, Gas Chromatography-Combustion-Isotope Ratio Mass Spectrometry ( GC-C-IRMS ), and comparesthe three methods. Compared with liquid-liquid extraction, solid-phase micro extraction, static headspace analysis, purge and trap method are all solvent-free enrichment techniques, producing no secondary pollution, less interference, and the resolution and accuracy of the analysis of GC-C-IRMS is improved. No, or little, isotopic mass fractionation occurred during the isotope analysis of chlorinated hydrocarbon in water by combining these solvent-free enrichment techniques with GC-C-IRMS, of which the precision of the analysis is less than l%e. The detection limit decreased along with the methods of static headspace analysis, solid-phase micro extraction, purge and trap method. Purge and trap is the most popular method because of its good reproducibility and low detection limit for the compound specific isotope analysis of chlorinated hydrocarbon in Water. The combinations of in-needle microextraction, in-tube microextraction, stir bar sorptive extraction or headspace sorptive extraction with GC-C-IRMS have a bright future.%高精度准确测定氯代烃单体碳同位素对示踪污染物来源,了解污染物的生物降解过程具有重要意义.在环境转化过程中,

  12. Antimicrobial Pesticides

    Science.gov (United States)

    ... US EPA US Environmental Protection Agency Search Search Pesticides Share Facebook Twitter Google+ Pinterest Contact Us You are here: EPA Home » Pesticides » Antimicrobial Pesticides Antimicrobial Pesticides News and Highlights Disinfection Hierarchy Workshop - October 7 ...

  13. Organochlorine Pesticide Residues in the Processing of Pressed Cheese

    OpenAIRE

    Dorin Ţibulcă; Mirela Jimborean; Dan Sălăgean; Ariana Caraba

    2015-01-01

    The persistence of pesticide residues in food and environment determined UN institutions to track their presence and establish rules of tolerance in foodstuffs of animal origin. Pesticide use leads to their presence as residue in foods. The research objectives were to establish the level of organo-chlorine pesticides in raw milk and their evolution during the process of obtaining pressed cheese.

  14. Microbial and molecular techniques to evaluate and to implement in-situ biodegradation potential and activity at sites contaminated with aromatic and chlorinated hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Karg, F. [HPC Envirotec / France and HPC AG (Germany); Henkler, Ch. [Planreal (Switzerland)

    2005-07-01

    (Biochemical Laboratory of the Medical Faculty) the first PBG-SP : 'Pole Biotechnologique et Genetique - Sites Pollues' in France. The modern tools and approaches have been applied successfully at several field sites for the evaluation, implementation and on-going monitoring of the bio-restoration/ attenuation of various aromatic and chlorinated compounds. (authors)

  15. Snapping Turtles (Chelydra serpentina) from Canadian Areas of Concern across the southern Laurentian Great Lakes: Chlorinated and brominated hydrocarbon contaminants and metabolites in relation to circulating concentrations of thyroxine and vitamin A.

    Science.gov (United States)

    Letcher, Robert J; Lu, Zhe; de Solla, Shane R; Sandau, Courtney D; Fernie, Kimberly J

    2015-11-01

    The metabolites of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), as well as other halogenated phenolic contaminants (HPCs) have been shown to have endocrine-disrupting properties, and have been reported with increasing frequency in the blood of wildlife, and mainly in mammals and birds. However, little is known about the persistence, accumulation and distribution of these contaminants in long-lived freshwater reptiles. In the present study, in addition to a large suite of chlorinated and brominated contaminants, metabolites and HPCs, we assessed and compared hydroxylated (OH) PCBs and OH-PBDEs relative to PCBs and PBDEs, respectively, in the plasma of adult male common snapping turtles (Chelydra serpentina). Blood samples were collected from 62 snapping turtles (2001-2004) at 12 wetland sites between the Detroit River and the St. Lawrence River on the Canadian side of the Laurentian Great Lakes of North America. Turtles were sampled from sites designated as Areas of Concern (AOCs) and from a relatively clean reference site in southern Georgian Bay (Tiny Marsh), Lake Huron. Plasma concentrations of Σ46PCB (10-340 ng/g wet weight (ww)) and Σ28OH-PCB (3-83 ng/g ww) were significantly greater (pLake Erie compared with the reference site turtles. The HPC, pentachlorophenol (PCP), had a mean concentration of 9.6±1.1 ng/g ww. Of the 28 OH-CB congeners screened for, 4-OH-CB187 (42±7 ng/g ww) was the most concentrated of all HPCs measured. Of the 14 OH-BDE congeners examined, four (4'-OH-BDE17, 3-OH-BDE47, 5-OH-BDE47 and 4'-OH-BDE49) were consistently found in all plasma samples. p,p'-DDE was the most concentrated of the 18 organochlorine pesticides (OCPs) examined. The mean concentrations of circulating total thyroxine (TT4), dehydroretinol and retinol in the plasma of the male snapping turtles regardless of sampling site were 5.4±0.3, 81±4.7 and 291±13 ng/mL, respectively. Significant (pLake Erie and Lake Ontario (in 2001-2004) had

  16. Study on Equilibrium Adsorption of Volatile Chlorinated Hydrocarbons on Humid Soils%挥发性氯代烃在湿润土壤中的平衡吸附研究

    Institute of Scientific and Technical Information of China (English)

    孟凡勇; 刘锐; 小林刚; 万梅; 余素林; 陈吕军

    2012-01-01

    吸附是挥发性氯代烃(volatile chlorinated hydrocarbons,VCHs)赋存于土壤的主要机制之一.开展动态吸附实验,研究了4种常见VCHs污染物在我国8种典型土壤中的吸附平衡关系.结果表明,土壤在干燥条件下对VCHs气体的吸附能力要远大于湿润条件,且随含水率的升高吸附能力急剧下降,在含水率达到10%以后土壤吸附量趋于稳定.湿润土壤对三氯乙烯(TCE)、四氯乙烯(PCE)、1,1,1-三氯乙烷(MC)气体的吸附等温线符合Henry型吸附等温式,而1,1,2-三氯乙烷(1,1,2-TCA)符合Freundlich模型.VCHs在湿润土壤中的吸附量总体上与土壤有机碳(soil organic carbon,SOC)含量呈正相关,且受SOC类型和化合物极性影响较大.弱极性的TCE、PCE在土壤中的吸附能力与SOC含量呈严格正相关,而极性的MC、1,1,2-TCA在黑土等高碳土壤中不仅与SOC含量有关,还受到SOC物质组成的影响.建立了TCE和PCE在湿润土壤中的平衡吸附量预测模型,预测值与实测值相关性良好(n=80,R2=0.98).%Adsorption is one of the principal mechanisms for soil contamination by volatile chlorinated hydrocarbons(VCHs).Dynamic adsorption experiments were carried out to study the equilibrium adsorption of four common VCHs pollutants onto eight typical soils in China.Results showed that dry soils had far greater adsorption capacity than humid soils.The soil adsorption capacity sharply decreased with the increase in the soil water content,and then reached a plateau as the water content rose to 10% or above.The adsorption isotherms of trichloroethylene(TCE),tetrachloroethylene(PCE) and 1,1,1-trichloroethane(MC) could be fitted with Henry's equation,while the adsorption isotherms of 1,1,2-trichloroethane(1,1,2-TCA) could be fitted with Freundlich model.The adsorption capacities of VCHs on humid soils were principally influenced by the content of soil organic carbon(SOC),but sometimes also

  17. The hydrogen concentration as parameter to identify natural attenuation processes of volatile chlorinated hydrocarbons in ground water; Die Wasserstoffkonzentration als Parameter zur Identifizierung des natuerlichen Abbaus von leichtfluechtigen Chlorkohlenwasserstoffen (LCKW) im Grundwasser

    Energy Technology Data Exchange (ETDEWEB)

    Alter, M.D.

    2006-06-15

    In this study, the hydrogen concentration as parameter to identify natural attenuation processes of volatile chlorinated hydrocarbons was investigated. The currently accepted and recommended bubble strip method for hydrogen sampling was optimized, and a storage method for hydrogen samples was developed. Furthermore batch experiments with a dechlorinating mixed culture and pure cultures were carried out to study H{sub 2}-concentrations of competing redox processes. The extraction of hydrogen from ground water was optimized by a reduced inlet diameter of the usually applied gas sampling bulbs, allowing a maximal turbulent ow and gas transfer. With a gas volume of 10 ml and flow rates of 50 to 140 ml/min, the course of extraction almost followed the theoretical course of equilibration. At flow rates > 100 ml/min a equilibrium of 98% was achieved within 20 min. Until recently it was generally accepted that hydrogen samples can be stored only for 2 hours and therefore have to be analyzed immediately in the eld. Here, it was shown that eld samples can be stored for 1-3 days until analysis. For the dechlorination of tetrachloroethene (PCE), a hydrogen threshold concentration of 1-2 nM was found with the dechlorinating mixed culture as well as with a pure culture of Sulfurospirillum multivorans in combination with another pure culture Methanosarcina mazei. No dechlorination was detectable below this concentration. With the dechlorinating mixed culture, this finding is valid for all successive dechlorination steps until ethene. The hydrogen threshold concentration for denitrification were below the detection limit of 0,2 nM with the dechlorinating mixed culture. A threshold concentration of 3,1-3,5 nM was found for sulphate reduction and a threshold of 7-9 nM H{sub 2} for hydrogenotrophic methanogenesis. This implies that the natural dechlorination at contaminated sites is preferred to competing processes like sulphate reduction and methanogenesis. The threshold

  18. Conduction of a Pumping Test in a Typical Organo-chlorine Pesticide Contaminated Site%有机氯农药污染场地地下水抽水试验

    Institute of Scientific and Technical Information of China (English)

    陈莉娜; 滕加泉; 尹勇; 蒋鹏; 张华; 胡林潮

    2012-01-01

    During the process of industrial development and urban restructuring, a lot of contaminated sites evolved, that yield danger for human beings and the environment and therefore need do be remediated. In order to remediate contaminated sites a lot of remediation techniques are available. One of the conventional site remediation is the so called "pump & treat" technique, in which the groundwater is pumped and treated above the ground "on-site". In order to examine the feasibility of pump-treat remediation on a specific site in Changzhou, contaminated with organo-chlorine pesticides and to obtain relative design parameters for the pump-treat remediation, a pumping test was conducted. During the pumping test contaminants concentrations were monitored. According to the pumping test, the permeability coefficient of this contaminated site was 8.03 m -d'', the radius of influence was 117.1 m, respectively. The amount of single well pumping was not lower than 170 m3·d-1 and the recharging was 7 m3·h-1 at an average. These results indicated that the pump & treat remediation might be used for groundwater remediation at this site. The manner of recharge tap water could be used to slow down the decrease of water budget, but it affected the flow directions of groundwater. At the same time, the contaminants were pump out during the pumping process, and the closer to contaminated area, the more effectively it worked. Altogether, the concentrations of contaminants became lower during the pumping test conduction.%伴随城市化进程和产业结构调整,我国出现许多污染场地亟待修复.通过某典型有机氯农药污染场地抽水试验论证抽出-处理修复方案应用于该污染场地地下水修复的可行性及获取抽出-处理工程设计所需要的参数,同时监测了特征污染物的浓度变化特征.该污染场地的地下水渗透系数为8.03 m·d-1,抽水井影响半径为117.1 m,长期抽水试验获得的单口井抽水量不低于170m3·d-1

  19. On chlorinated hydrocarbons in the Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Sarkar, A.; SenGupta, R.

    The data available on the distribution of organochlorine compounds such as DDT and its metabolites, aldrin, dieldrin, endrin, isomers of HCH and the PCBs in the sediments, water, zooplankton, fish and seals from the Indian Ocean is reviewed. High...

  20. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of chlorinated pesticides in aquatic tissue by capillary-column gas chromatography with electron-capture detection

    Science.gov (United States)

    Leiker, Thomas J.; Madsen, J.E.; Deacon, J.R.; Foreman, W.T.

    1995-01-01

    A method for the determination of chlorinated organic compounds in aquatic tissue by dual capillary-column gas chromatography with electron-capture detection is described. Whole-body-fish or corbicula tissue is homogenized, Soxhlet extracted, lipid removed by gel permeation chromatography, and fractionated using alumina/silica adsorption chromatography. The extracts are analyzed by dissimilar capillary-column gas chromatography with electron-capture detection. The method reporting limits are 5 micrograms per kilogram (μg/kg) for chlorinated compounds, 50 μg/kg for polychlorinated biphenyls, and 200 μg/kg for toxaphene.

  1. Types of pesticides and determination of their residues

    International Nuclear Information System (INIS)

    The pesticide is any material or component used to protect from pests. Its toxic effect is related to the chemical structure, which can be divided into 3 types : 1- Metal pesticides : Sulphur, cupper, zinc, mercury; 2- Vegetal pesticides : advanced and less toxic to the general health; 3- Synthetic organo pesticides : organo chlorine, organophosphorous, carbamate and pyrethroids. Pesticides in the soil undergo biological dissociation according to their concentration and chemical structure. High concentration of the pesticides in the soil may lead to fertility decrease due to destruction of micro-organisms by the pesticides. Many methods are used to analyze the residues of pesticides in plant or soil : 1- Chromatographic methods : Gas chromatography, gas liquid chromatography and high performance liquid chromatography; 2- Spectroscopy methods : spectrophotometer and mass spectrometer; 3- Isotopic methods : based on tracers technique which is the most sensitive and accurate method and can estimate minor amounts of the pesticides. (author)

  2. Organochlorine Pesticide Residues in the Processing of Pressed Cheese

    Directory of Open Access Journals (Sweden)

    Dorin Ţibulcă

    2015-11-01

    Full Text Available The persistence of pesticide residues in food and environment determined UN institutions to track their presence and establish rules of tolerance in foodstuffs of animal origin. Pesticide use leads to their presence as residue in foods. The research objectives were to establish the level of organo-chlorine pesticides in raw milk and their evolution during the process of obtaining pressed cheese.

  3. Development of an analysis method for determining chlorinated hydrocarbons in marine sediments and suspended matter giving particular consideration to supercritical fluid extraction; Entwicklung eines Analysenverfahrens zur Bestimmung von chlorierten Kohlenwasserstoffen in marinen Sedimenten und Schwebstoffen unter besonderer Beruecksichtigung der ueberkritischen Fluidextraktion

    Energy Technology Data Exchange (ETDEWEB)

    Sterzenbach, D.

    1997-11-01

    The purpose of the present study was to develop an analysis method for chlorinate hydrocarbons in marine environments using supercritical fluid extraction (SFE) instead of conventional approaches. In order to apply this extraction method the available SFE device had to be extended and all the individual steps of the analysis method had to be optimised and adapted. As chlorinated hydrocarbons only occur at very low concentrations in marine environments (ppm to ppt range) the analysis method had to be extremely sensitive. High sensitivity, in town, is generally associated with a high susceptibility of an analysis method to faults through contamination or losses. This meant that the entire method and all its individual steps had to scrutinised for such weak points and improved where necessary. A method for sampling suspended matter in marine environments had to be developed which permits efficient separation of the smallest possible particles from seawater. The designated purpose of the developed analysis method is to deal with topical aspects of marine chemistry relating to sources, transport, distribution, and the fate of chlorinated hydrocarbons in marine environments. (orig.) [Deutsch] Ziel der vorliegenden Arbeit ist, ein Analysenverfahren fuer chlorierte Kohlenwasserstoffe in der marinen Umwelt zu entwickeln. Dabei soll die ueberkritische Fluidextraktion (SFE) anstelle herkoemmlicher Verfahren eingesetzt werden. Fuer die Anwendung dieser Extraktionsmethode ist es erforderlich, das zur Verfuegung stehende SFE-Geraet zu erweitern und saemtliche Teilschritte des Analysenverfahrens zu optimieren und auf diese Methode abzustimmen. Der Umstand, dass die chlorierten Kohlenwasserstoffe nur in sehr geringen Konzentrationen in der marinen Umwelt vorkommen (ppm- bis ppt-Bereich), erfordert eine sehr hohe Empfindlichkeit des Analysenverfahrens. Eine hohe Empfindlichkeit bedingt eine grosse Stoeranfaelligkeit des Analysenverfahrens durch Kontaminationen oder Verluste. Aus

  4. Air-sea Exchange of Polycyclic Aromatic Hydrocarbons (PAHs), Polychlorinated Biphenyls (PCBs), Organochlorine Pesticides (OCPs) and Polybrominated Diphenyl Ethers (PBDEs) in the Mediterranean Sea

    Science.gov (United States)

    Lammel, G. P.; Heil, A.; Kukucka, P.; Meixner, F. X.; Mulder, M. D.; Prybilova, P.; Prokes, R.; Rusina, T. S.; Song, G. Z.; Vrana, B.

    2015-12-01

    The marine atmospheric environment is a receptor for persistent organic pollutants (POPs) which are advected from sources on land, primary, such as biomass burning by-products (PAHs, dioxins), and secondary, such as volatilization from contaminated soils (PCBs, pesticides). Primary sources do not exist in the marine environment, except for PAHs (ship engines) but following previous atmospheric deposition, the sea surface may turn to a secondary source by reversal of diffusive air-sea mass exchange. No monitoring is in place. We studied the vertical fluxes of a wide range of primary and secondary emitted POPs based on measurements in air and surface seawater at a remote coastal site in the eastern Mediterranean (2012). To this end, silicon rubbers were used as passive water samplers, vertical concentration gradients were determined in air and fluxes were quantified based on Eddy covariance. Diffusive air-sea exchange fluxes of hexachlorocyclohexanes (HCHs) and semivolatile PAHs were found close to phase equilibrium, except one PAH, retene, a wood burning tracer, was found seasonally net-volatilisational. Some PCBs, p,p'-DDE, penta- and hexachlorobenzene (PeCB, HCB) were mostly net-depositional, while PBDEs were net-volatilizational. Fluxes determined at a a remote coastal site ranged -33 - +2.4 µg m-2 d-1 for PAHs and -4.0 - +0.3 µg m-2 d-1for halogenated compounds ( 0 means net-volatilization). It is concluded that nowadays in open seas more pollutants are undergoing reversal of the direction of air-sea exchange. Recgional fire activity records in combination with box model simulations suggest that deposition of retene during summer is followed by a reversal of air-sea exchange. The seawater surface as secondary source of pollution should be assessed based on flux measurements across seasons and over longer time periods.

  5. Multi-class, multi-residue analysis of pesticides, polychlorinated biphenyls, polycyclic aromatic hydrocarbons, polybrominated diphenyl ethers and novel flame retardants in fish using fast, low-pressure gas chromatography-tandem mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Sapozhnikova, Yelena, E-mail: yelena.sapozhnikova@ars.usda.gov [US Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center, 600 East Mermaid Lane, Wyndmoor, PA 193038 (United States); Lehotay, Steven J. [US Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center, 600 East Mermaid Lane, Wyndmoor, PA 193038 (United States)

    2013-01-03

    Highlights: Black-Right-Pointing-Pointer A method for analysis of POPs and novel flame retardants in catfish was developed. Black-Right-Pointing-Pointer The method is based on a QuEChERS extraction, d-SPE clean-up and low pressure GC/MS-MS. Black-Right-Pointing-Pointer The method validation demonstrated good recoveries and low detection limits. Black-Right-Pointing-Pointer The method was successfully applied for analysis of catfish samples from the market. - Abstract: A multi-class, multi-residue method for the analysis of 13 novel flame retardants, 18 representative pesticides, 14 polychlorinated biphenyl (PCB) congeners, 16 polycyclic aromatic hydrocarbons (PAHs), and 7 polybrominated diphenyl ether (PBDE) congeners in catfish muscle was developed and evaluated using fast low pressure gas chromatography triple quadrupole tandem mass spectrometry (LP-GC/MS-MS). The method was based on a QuEChERS (quick, easy, cheap, effective, rugged, safe) extraction with acetonitrile and dispersive solid-phase extraction (d-SPE) clean-up with zirconium-based sorbent prior to LP-GC/MS-MS analysis. The developed method was evaluated at 4 spiking levels and further validated by analysis of NIST Standard Reference Materials (SRMs) 1974B and 1947. Sample preparation for a batch of 10 homogenized samples took about 1 h/analyst, and LP-GC/MS-MS analysis provided fast separation of multiple analytes within 9 min achieving high throughput. With the use of isotopically labeled internal standards, recoveries of all but one analyte were between 70 and 120% with relative standard deviations less than 20% (n = 5). The measured values for both SRMs agreed with certified/reference values (72-119% accuracy) for the majority of analytes. The detection limits were 0.1-0.5 ng g{sup -1} for PCBs, 0.5-10 ng g{sup -1} for PBDEs, 0.5-5 ng g{sup -1} for select pesticides and PAHs and 1-10 ng g{sup -1} for flame retardants. The developed method was successfully applied for analysis of catfish samples

  6. Multi-class, multi-residue analysis of pesticides, polychlorinated biphenyls, polycyclic aromatic hydrocarbons, polybrominated diphenyl ethers and novel flame retardants in fish using fast, low-pressure gas chromatography–tandem mass spectrometry

    International Nuclear Information System (INIS)

    Highlights: ► A method for analysis of POPs and novel flame retardants in catfish was developed. ► The method is based on a QuEChERS extraction, d-SPE clean-up and low pressure GC/MS–MS. ► The method validation demonstrated good recoveries and low detection limits. ► The method was successfully applied for analysis of catfish samples from the market. - Abstract: A multi-class, multi-residue method for the analysis of 13 novel flame retardants, 18 representative pesticides, 14 polychlorinated biphenyl (PCB) congeners, 16 polycyclic aromatic hydrocarbons (PAHs), and 7 polybrominated diphenyl ether (PBDE) congeners in catfish muscle was developed and evaluated using fast low pressure gas chromatography triple quadrupole tandem mass spectrometry (LP-GC/MS–MS). The method was based on a QuEChERS (quick, easy, cheap, effective, rugged, safe) extraction with acetonitrile and dispersive solid-phase extraction (d-SPE) clean-up with zirconium-based sorbent prior to LP-GC/MS–MS analysis. The developed method was evaluated at 4 spiking levels and further validated by analysis of NIST Standard Reference Materials (SRMs) 1974B and 1947. Sample preparation for a batch of 10 homogenized samples took about 1 h/analyst, and LP-GC/MS–MS analysis provided fast separation of multiple analytes within 9 min achieving high throughput. With the use of isotopically labeled internal standards, recoveries of all but one analyte were between 70 and 120% with relative standard deviations less than 20% (n = 5). The measured values for both SRMs agreed with certified/reference values (72–119% accuracy) for the majority of analytes. The detection limits were 0.1–0.5 ng g−1 for PCBs, 0.5–10 ng g−1 for PBDEs, 0.5–5 ng g−1 for select pesticides and PAHs and 1–10 ng g−1 for flame retardants. The developed method was successfully applied for analysis of catfish samples from the market.

  7. Organic Pesticide Ingredients

    Science.gov (United States)

    ... Control a pest Integrated Pest Management What are pesticides? Herbicides Disinfectants Fungicides Insecticides Natural and Biological Pesticides ... Other types of pesticides Disponible en español Organic Pesticide Ingredients Organic foods are not necessarily pesticide-free. ...

  8. Pesticides and Human Health

    Science.gov (United States)

    ... Control a pest Integrated Pest Management What are pesticides? Herbicides Disinfectants Fungicides Insecticides Natural and Biological Pesticides ... Rodenticides Other types of pesticides Disponible en español Pesticides and Human Health Pesticides have a specific purpose ...

  9. Water Treatment Technology - Chlorination.

    Science.gov (United States)

    Ross-Harrington, Melinda; Kincaid, G. David

    One of twelve water treatment technology units, this student manual on chlorination provides instructional materials for nine competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on the following areas: purpose and process of chlorination, chlorine…

  10. Pesticide Movement

    Science.gov (United States)

    Pesticides generally include herbicides, insecticides and fungicides that play an important role in maintaining worldwide food and fiber production by controlling weeds that compete for water and nutrients or by eliminating pests that reduce yields. In the future, the role of pesticides and fertili...

  11. Reaction products of chlorine dioxide.

    OpenAIRE

    Stevens, A A

    1982-01-01

    Inspection of the available literature reveals that a detailed investigation of the aqueous organic chemistry of chlorine dioxide and systematic identification of products formed during water disinfection has not been considered. This must be done before an informed assessment can be made of the relative safety of using chlorine dioxide as a disinfectant alternative to chlorine. Although trihalomethanes are generally not formed by the action of chlorine dioxide, the products of chlorine dioxi...

  12. RESEARCH ON MATHEMATICAL SIMULATION OF RESIDUAL CHLORINE DECAY AND OPTIMIZATION OF CHLORINATION ALLOCATION OF URBAN WATER DISTRIBUTION SYSTEM

    Institute of Scientific and Technical Information of China (English)

    TIAN Yi-mei; CHI Hai-yan; LI Hong; SHAN Jin-lin; ZHAI Chun-nian

    2005-01-01

    The concentration of Residual Chlorine (RC) frequently violates the standard in situations of urban water distribution system with large water supply area and long time of distribution.If chlorine dosage increases within water treatment plant, although RC in distribution system could meet water quality standard, Disinfection By-Products (DBPs) such as hydrocarbon halide rises.In the paper, a mathematical model of chlorine allocation optimization was presented based on reaction kinetics mechanism and optimization theory to solve the problem.The model includes the objective function of minimizing annual operation cost and constraints of RC standard and rational chlorination station distribution, and solving by 0-1 Integer Programming (IP).The model had been applied to a real water distribution system.The simulation results of the model showed that adding chlorine in water distribution system remarkably improved water quality and reduced the operation cost by 49.3% per year less than chlorine dosed only in water treatment plant to meet RC standard.The results prove adding chlorine in water distribution system based on the model can bring both technological and economic advancement.

  13. Zirconia concentrate chlorination

    International Nuclear Information System (INIS)

    Chlorination experiments were conducted in order to study the kinetics of gasification of the zirconium oxide present in the zirconia concentrate. The variables studied are temperature (1173 to 1373 K), percentage of reducing agent (12 to 36%) and porosity (22 to 30%). The results indicated a greater influence of temperature and percentage of reducing agent as well as allowed the conclusion that a balance between the levels of these variables is an important factor in the appropriate chlorination conditions. (author)

  14. POST-REMEDIATION BIOMONITORING OF PESTICIDES AND OTHER CONTAMINANTS IN MARINE WATERS AND SEDIMENT NEAR THE UNITED HECKATHORN SUPERFUND SITE, RICHMOND, CALIFORNIA

    Energy Technology Data Exchange (ETDEWEB)

    Antrim, Liam D.; Kohn, Nancy P.

    2000-09-06

    Marine sediment remediation at the United Heckathorn Superfund Site was completed in April 1997. Water and mussel tissues were sampled in February 1999 from four stations near Lauritzen Canal in Richmond, California, for Year 2 of post-remediation monitoring of marine areas near the United Heckathorn Site. Dieldrin and dichlorodiphenyl trichloroethane (DDT) were analyzed in water samples, tissue samples from resident mussels, and tissue samples from transplanted mussels deployed for 4 months. Mussel tissues were also analyzed for polychlorinated biphenyls (PCB), which were detected in sediment samples. Chlorinated pesticide concentrations in water samples were similar to preremediation levels and did not meet remediation goals. Biomonitoring results indicated that the bioavailability of chlorinated pesticides has been reduced from preremediation levels both in the dredged area and throughout Richmond Harbor. Total DDT and dieldrin concentrations in mussel tissues were lower than measured levels from preremediation surveys and also lower than Year 1 levels from post-remediation biomonitoring. Sediment analyses showed the presence of elevated DDT, dieldrin, PCB aroclor 1254, and very high levels of polynuclear aromatic hydrocarbons (PAH) in Lauritzen Channel.

  15. Tissue-specific accumulation and lactational transfer of polychlorinated biphenyls, chlorinated pesticides, and brominated flame retardants in hooded seals (Cistophora cristata) from the Gulf of St. Lawrence: Applications for monitoring

    International Nuclear Information System (INIS)

    Accumulation and mother-pup transfer of halogenated organic contaminants was studied in hooded seal tissues from eastern Canada. Blubber polychlorinated biphenyl (PCB) and total pesticide concentrations were relatively high, possibly due to their high trophic level and demersal feeding habits. Blood plasma showed the lowest contaminant concentrations compared to blubber and liver, possibly due to a lower affinity of these compounds to lipoproteins in blood plasma. Total contaminant body burden correlated well with blubber, liver, and milk contaminants, but not with blood plasma contaminants, indicating that blood plasma might be less suitable to monitor contaminants in hooded seals. Lactational transfer favored less lipophilic contaminants and was associated with relatively high blood plasma PCB and polybrominated diphenyl ether concentrations in females. Despite lactational transfer, females did not show significantly lower blubber contaminant concentrations or burdens than males. This might be caused by their low blubber, and thus contaminant, loss during lactation compared to other species. - Blood plasma contaminant concentrations differ from those in other tissues and might therefore be unsuitable for contaminant monitoring in hooded seals

  16. National Pesticide Information Center

    Science.gov (United States)

    ... any pest." Herbicides Disinfectants Fungicides Insecticides Natural and Biological Pesticides Repellents Rodenticides Other types of pesticides Local Contacts Find local pesticide & pest control information Pesticide Information and Resources: Frequently Asked Questions: ...

  17. What Is a Pesticide?

    Science.gov (United States)

    ... Twitter Google+ Pinterest Contact Us Basic Information about Pesticide Ingredients Pesticide products contain both "active" and "inert" ingredients: What is a Pesticide? A pesticide is any substance or mixture of ...

  18. Breakpoint chlorination curves of greywater.

    Science.gov (United States)

    March, J G; Gual, M

    2007-08-01

    A study on chlorination of raw greywater with hypochlorite is reported in this paper. Samples were chlorinated in a variety of conditions, and residual chlorine (Cl2) was measured spectrophotometrically. For each sample, the chlorination curve (chlorine residuals versus chlorine dose) was obtained. Curves showed the typical hump-and-dip profile attributable to the formation and destruction of chloramines. It was observed that, after reactions with strong reductants and chloramines-forming compounds, the remaining organic matter exerted a certain demand of chlorine. The evolution of chlorination curves with addition of ammonia and dodecylbencene sulfonate sodium salt and with dilution of the greywater sample were studied. In addition, chlorination curves at several contact times have been obtained, resulting in slower chlorine decay in the hump zone than in the dip zone. In addition, the decay of coliforms in chlorinated samples was also investigated. It was found that, for a chlorination dosage corresponding to the maximum of the hump zone (average 8.9 mg Cl2/ L), samples were negative in coliforms after 10 to 30 minutes of contact time. After-growth was not observed within 3 days after chlorination. Implications in chlorination treatments of raw greywater can be derived from these results. PMID:17824528

  19. Application of thermal desorption to the development of a gas chromatographic/mass spectrometric method for the determination of toluene, chlorinated aromatic hydrocarbons, and 2,3,7,8-tetrachlorodibenzo-p-dioxin in combustion emissions.

    Science.gov (United States)

    Donaldson, John D; Grimes, Susan M; Mehta, Lina; Jafari, Ahmad J

    2003-01-01

    A fast and accurate analytical method, which uses commercially available adsorbents (Tenax TA, Carbotrap B and C, and Carbosieve S-III), was developed for the sampling and determination of aromatic hydrocarbons, chloroaromatic compounds, and 2,3,7,8-tetrachlorodibenzo-p-dioxin. The breakthrough volume data show that Carbotrap C has a good capacity for compounds of high molecular weight, whereas Carbosieve S-III and Tenax TA are efficient for volatile compounds. The organic components are thermally desorbed and transferred to a gas chromatograph/mass spectrometer. Importantly, thermal desorption avoids conventional solvent extraction procedures and also allows reuse of adsorbent tubes. Preliminary results for recovery of analytes from tubes packed with single adsorbent prove that a single-adsorbent bed is not capable of sampling a wide range of compounds. The best method to obtain the desired collection and desorption properties is to use adsorbent tubes containing several different materials. The results of optimization studies are summarized. PMID:12607738

  20. Obsolete pesticides

    Science.gov (United States)

    Showstack, Randy

    Several hundred tons of obsolete pesticide stocks worldwide will pose a threat to humans and the environment until the year 2030 in some regions, unless funding for waste disposal is significantly increased, the United Nations Food and Agriculture Organization (FAO) said in a message directed to donor governments and industry on May 24.“Deadly chemicals are contaminating the soils, groundwater, irrigation, and drinking water,” said Amemayehu Wodageneh, senior expert on obsolete pesticides for FAO. “These ‘forgotten’ stocks are a serious risk, [and] they could cause an environmental tragedy in rural areas and big cities. There is hardly any developing country that is not affected by the hazards of obsolete pesticides.”

  1. Chlorine, Chloramine, Chlorine Dioxide, and Ozone Susceptibility of Mycobacterium avium

    OpenAIRE

    Taylor, Robert H.; Joseph O. Falkinham; Norton, Cheryl D.; LeChevallier, Mark W.

    2000-01-01

    Environmental and patient isolates of Mycobacterium avium were resistant to chlorine, monochloramine, chlorine dioxide, and ozone. For chlorine, the product of the disinfectant concentration (in parts per million) and the time (in minutes) to 99.9% inactivation for five M. avium strains ranged from 51 to 204. Chlorine susceptibility of cells was the same in washed cultures containing aggregates and in reduced aggregate fractions lacking aggregates. Cells of the more slowly growing strains wer...

  2. Spatial and temporal variability of inorganic chlorine in Northwestern Europe

    Science.gov (United States)

    Sommariva, R.; Hollis, L. D. J.; Baker, A. R.; Ball, S. M.; Bell, T. G.; Cordell, R. L.; Fleming, Z.; Gaget, M.; Yang, M. X.; Monks, P. S.

    2015-12-01

    Chlorine is well known to be a strong oxidant in the atmosphere;chlorine reactivity impacts the formation of tropospheric ozone, theoxidation of methane and non-methane hydrocarbons, and the cycling ofnitrogen, sulphur and mercury. An accurate assessment of the roleplayed by chlorine in tropospheric chemical processes is complicatedby the scarce knowledge of its sources, sinks and distribution.We report observations of inorganic chlorine species (Cl2, ClNO2,particulate chloride) taken over the period 2014-2015 at threedifferent locations in Britain: an urban site a hundred kilometersfrom the ocean (Leicester), a coastal site mostly affected by shiptraffic (Penlee Point, Cornwall) and a coastal site experiencingeither clean air from the North Sea or polluted air from inland(Weybourne, Norfolk).This dataset provides a first look into the geographical distributionand seasonal variability of chlorine in Northwestern Europe: theresults suggest that, during the night, ClNO2 is ubiquitous withconcentrations in the range of hundreds to thousands of pptV at alllocations, whereas Cl2 can be observed only at coastal sites, withconcentrations of a few tens of pptV. The implications of thewidespread presence of these forms of inorganic chlorine for ozoneproduction and, in general, for the oxidative processes in the loweratmosphere are discussed with the help of a wide range of supportingmeasurements.

  3. Aromatic polycyclic hydrocarbons in the environment - I - Sources. Les hydrocarbures aromatiques polycycliques chlores presents dans l'environnement - I - Sources

    Energy Technology Data Exchange (ETDEWEB)

    Bard, D. (Electricite de France (EDF), 75 - Paris (France))

    Chlorinated aromatic polycyclic hydrocarbons, which include polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorobiphenyls (PCBs) and others, are persistent, ubiquitous compounds in the environment of industrialized countries. In this paper, we present a short review of the known sources of these compounds. These include industrial sources, such as processing, accidents, and waste disposal of chlorophenols, diphenylethers herbicides, chlorinated aliphatics and PCBs processing: petroleum refining industry, municipal and industrial waste incineration; reclamation or recycling of copper and steel; pulp and paper cork, pesticides (hexachlorocyclohexanes-HCH) and metallurgical (nickel and magnesium) processing. In addition, these compounds appear as being formed naturally in traces quantities in many circumstances of organic matter combustion or pyrolysis. As a result, they have been found in chimney soots, stoves... They are also produced in car exhausts. Another natural mechanism of formation could be the photochemical degradation of higher chlorinated isomers to lower ones. Since it cannot be excluded that these compounds may be carcinogenic for humans at low doses, efforts should be made to limit to as low as reasonably achievable the inputs to the environment of HAPC from artificial origin. (Author). 46 refs., 8 tabs.

  4. Chlorine dioxide as phenol and H2S scavenger - formation of halogenated phenols and subsequent environmental risk

    Energy Technology Data Exchange (ETDEWEB)

    Melbye, Alf G.; Faksness, Liv-Guri; Knudsen, Boerre Leif

    2006-03-15

    Formation of halogenated phenols as side products from treatment of produced water with aqueous chlorine dioxide has been investigated. The literature describes formation of halogenated hydrocarbons in effluent treatment using chlorine, hypochlorite and chlorine dioxide. A new chlorine dioxide product, originally intended as a H2S scavenger in the oil and gas industry, has been tested both as a phenol scavenger and H2S-scavenger for produced water applications. The concern about the possible formation of halogenated by-products initiated laboratory testing of chlorine dioxide as phenol and H2S scavenger for produced water applications. The tests also included synthetic matrixes containing phenols, and the tests show that halogenated phenols, mainly brominated species, are found in produced water after treatment with chlorine dioxide. Due to potential environmental risk from halogenated organic contaminants, the use of chlorine dioxide as phenol and H2S scavenger is not recommended. (Author)

  5. THE COMPATIBILITY OF BLENDS OF POLY(VINYL CHLORIDE) OR CHLORINATED POLY(VINYL CHLORIDE) WITH POLY(METHYL METHACRYLATE)

    Institute of Scientific and Technical Information of China (English)

    WANG Qingguo; CHENG Rongshi

    1988-01-01

    IR spectral shifts of carbonyl vibrational absorption for ethyl acetate, which acts analogically as the structural unit of poly(methyl methacrylate), in cyclohexane, chloroform, chlorinated paraffins, poly(vinyl chloride) and chlorinated poly(vinyl chloride) were measured. The results suggest that there are specific interactions between the carbonyl groups and the chlorinated hydrocarbons which could be responsible for the apparent compatibility of poly(vinyl chloride) -poly(methyl methacrylate) and chlorinated poly(vinyl chloride) -poly(methyl methacrylate) blends. Additionally, the effects of the preparation mode of blend films on phase separation and observed compatibility are discussed.

  6. Applying Pesticides Safely

    OpenAIRE

    Latimer, Joyce G.

    2009-01-01

    Proper use of pesticides is essential for your safety and for that of the environment. Pesticides must be used correctly to be effective. This publication reviews the key factors in the proper use of pesticides.

  7. Compound specific isotope analysis to investigate pesticide degradation in lysimeter experiments at field conditions

    Science.gov (United States)

    Ryabenko, Evgenia; Elsner, Martin; Bakkour, Rani; Hofstetter, Thomas; Torrento, Clara; Hunkeler, Daniel

    2015-04-01

    The frequent detection of organic micropollutants such as pesticides, consumer care products or pharmaceuticals in water is an increasing concern for human and ecosystem health. Degradation analysis of these compounds can be challenging in complex systems due to the fact that metabolites are not always found and mass balances frequently cannot be closed. Many abiotic and biotic degradation pathways cause, however, distinct isotope fractionation, where light isotopes are transferred preferentially from the reactant to the product pool (normal isotope fractionation). Compound-specific isotope analysis (CSIA) of multiple elements is a particularly powerful method to evaluate organic micropollutant transformation, because it can even give pathway-specific isotope fractionation (1,2). Available CSIA field studies, however, have focused almost exclusively on volatile petroleum and chlorinated hydrocarbons, which are present in high concentrations in the environment and can be extracted easily from water for GC-IRMS analysis. In the case of micropollutants, such as pesticides, CSIA in more challenging since it needs to be conducted at lower concentrations and requires pre-concentration, purification and high chromatographic performance (3). In this study we used lysimeters experiments to analyze transformation of atrazine, acetochlor, metolachlor and chloridazone by studying associated isotope fractionation. The project combines a) analytical method development for CSIA, b) identification of pathways of micropollutant degradation and c) quantification of transformation processes under field condition. The pesticides were applied both, at the soil surface and below the top soil under field-relevant concentrations in May 2014. After typical irrigation of the lysimeters, seepage water was collected in 50L bottles and stored for further SPE and CSIA. Here we present the very first result of a) analytical method development, b) improvement of SPE methods for complex pesticide

  8. Post-remediation biomonitoring of pesticides and other contaminants in marine waters and sediment near the United Heckathorn Superfund Site, Richmond, California

    Energy Technology Data Exchange (ETDEWEB)

    LD Antrim; NP Kohn

    2000-05-26

    dieldrin concentrations in mussel tissues were dramatically lower than measured levels from preremediation surveys and also lower than Year 1 levels from post-remediation biomonitoring. The lowest levels were found at the Richmond Inner Harbor Channel station (4.1 {micro}g/kg total DDT and 0.59 {micro}g/kg dieldrin, wet weight; mean of resident and transplant mussels). Mean chlorinated pesticide concentrations were highest at Lauritzen Canal/End (82 {micro}g/kg total DDT and 7.1 {micro}g/kg dieldrin, wet weight), followed by Lauritzen Canal/Mouth (22 {micro}/kg total DDT and 1.7 {micro}g/kg dieldrin, wet weight) and Santa Fe Channel/End (7.5 {micro}g/kg total DOT and 0.61 {micro}g/kg dieldrin, wet weight). These levels are 95% to 99% lower than those recorded by the California State Mussel Watch program prior to EPA's response actions. The levels of PCBs in mussel tissue were also reduced by 93% to 97% from preremediation levels. Surface sediment concentrations of dieldrin and DDT in November 1998 were highest in samples from the head or north end of Lauritzen Canal and progressively lower toward the mouth, or south end. Total DDT ranged from 130 ppm (dry weight) at the north end to 3 ppm at the south end. Dieldrin concentrations decreased from 3,270 ppb (dry weight) at the north end to 52 ppb at the south end. These results confirmed elevated pesticide concentrations in sediments collected from Lauritzen Channel by Anderson et al. (1999). The pesticide concentrations were lower than maximum concentrations found in the 1993 Remedial Investigation but comparable to the median levels measured before remediation was completed. Sediment analyses also showed the presence of elevated PCB aroclor 1254, and very high levels of polynuclear aromatic hydrocarbons (PAH) in Lauritzen Channel.

  9. Post-remediation biomonitoring of pesticides and other contaminants in marine waters and sediment near the United Heckathorn Superfund Site, Richmond, California; TOPICAL

    International Nuclear Information System (INIS)

    dieldrin concentrations in mussel tissues were dramatically lower than measured levels from preremediation surveys and also lower than Year 1 levels from post-remediation biomonitoring. The lowest levels were found at the Richmond Inner Harbor Channel station (4.1(micro)g/kg total DDT and 0.59(micro)g/kg dieldrin, wet weight; mean of resident and transplant mussels). Mean chlorinated pesticide concentrations were highest at Lauritzen Canal/End (82(micro)g/kg total DDT and 7.1(micro)g/kg dieldrin, wet weight), followed by Lauritzen Canal/Mouth (22(micro)/kg total DDT and 1.7(micro)g/kg dieldrin, wet weight) and Santa Fe Channel/End (7.5(micro)g/kg total DOT and 0.61(micro)g/kg dieldrin, wet weight). These levels are 95% to 99% lower than those recorded by the California State Mussel Watch program prior to EPA's response actions. The levels of PCBs in mussel tissue were also reduced by 93% to 97% from preremediation levels. Surface sediment concentrations of dieldrin and DDT in November 1998 were highest in samples from the head or north end of Lauritzen Canal and progressively lower toward the mouth, or south end. Total DDT ranged from 130 ppm (dry weight) at the north end to 3 ppm at the south end. Dieldrin concentrations decreased from 3,270 ppb (dry weight) at the north end to 52 ppb at the south end. These results confirmed elevated pesticide concentrations in sediments collected from Lauritzen Channel by Anderson et al. (1999). The pesticide concentrations were lower than maximum concentrations found in the 1993 Remedial Investigation but comparable to the median levels measured before remediation was completed. Sediment analyses also showed the presence of elevated PCB aroclor 1254, and very high levels of polynuclear aromatic hydrocarbons (PAH) in Lauritzen Channel

  10. Reactions of aqueous chlorine and chlorine dioxide with model food compounds.

    OpenAIRE

    Fukayama, M Y; Tan, H; Wheeler, W B; Wei, C I

    1986-01-01

    Chlorine and chlorine dioxide (ClO2), common disinfecting and bleaching chemicals used in the food industry, are potent oxidizing and chlorinating agents. Unfortunately, little is known about the nature of the reactions of chlorine with organic food constituents. This presentation reviews published information concerning the reactions of chlorine gas (Cl2[g]), aqueous chlorine, and ClO2 with model food compounds, the fate of chlorine during the chlorination of specific food products, and the ...

  11. The chlorination of cooling water

    International Nuclear Information System (INIS)

    After reviewing the means of fighting biological pollution of cooling water circuits in nuclear power stations, the authors describe the chlorination treatment methods used by EDF. This deals with the massive shock chlorination of the cooling towers and the continuous low-level chlorination of coastal nuclear power stations. In both areas, the Research and Development Board of EDF has carried out and encouraged research with the aim of improving circuit protection, while still protecting the aquatic eco-system against damage that might be caused by waste chlorinated water

  12. Microbial transformation of highly persistent chlorinated pesticides and industrial chemicals.

    OpenAIRE

    Middeldorp, P.J.M.

    1997-01-01

    Organic pollutants can be transformed, both in unsaturated and saturated areas of the soil, by means of biologically mediated reactions. The potential of soil microorganisms to clean up polluted soils is enormous. However, soil systems are highly heterogeneous with respect to the spatial distribution of substrates, nutrients and microorganisms, and also with respect to various phases and interfaces (e.g. water, air, minerals, organic matter). To come to the development of appropriate soil bio...

  13. Microbial transformation of highly persistent chlorinated pesticides and industrial chemicals.

    NARCIS (Netherlands)

    Middeldorp, P.J.M.

    1997-01-01

    Organic pollutants can be transformed, both in unsaturated and saturated areas of the soil, by means of biologically mediated reactions. The potential of soil microorganisms to clean up polluted soils is enormous. However, soil systems are highly heterogeneous with respect to the spatial distributio

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-09-01

    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.

  15. Photophysical properties and localization of chlorins substituted with methoxy groups, hydroxyl groups and alkyl chains in liposome-like cellular membrane

    Energy Technology Data Exchange (ETDEWEB)

    Al-Omari, S [Department of Physics, Hashemite University, Zarqa 13115 (Jordan)

    2007-06-01

    Some of the photophysical properties (stationary absorbance and fluorescence, fluorescence decay times and singlet oxygen quantum yields) of chlorins substituted with methoxy groups, hydroxyl groups and hydrocarbonic chains were studied in ethanol and dipalmitoyl-phosphatidylcholine (DPPC) liposomes using steady-state and time-resolved fluorescence spectroscopies. The photophysical behaviors of the chlorins in liposomes like cellular membrane were compared with those obtained from chlorin-liposome systems delivered to Jurkat cells in order to select potent photosensitizers for the photodynamic treatment of cancer. The localization of the studied chlorins inside liposomes was found to depend strongly on the substituents of chlorins. Absorption spectra of chlorins embedded in DPPC-liposomes have been recorded in the temperature range of 20-70 deg. C. It is demonstrated that the location of the chlorin molecules depends on the phase state of the phospholipids. These observations are confirmed by the fluorescence lifetimes, singlet oxygen lifetimes and singlet oxygen quantum yields results.

  16. Photophysical properties and localization of chlorins substituted with methoxy groups, hydroxyl groups and alkyl chains in liposome-like cellular membrane

    International Nuclear Information System (INIS)

    Some of the photophysical properties (stationary absorbance and fluorescence, fluorescence decay times and singlet oxygen quantum yields) of chlorins substituted with methoxy groups, hydroxyl groups and hydrocarbonic chains were studied in ethanol and dipalmitoyl-phosphatidylcholine (DPPC) liposomes using steady-state and time-resolved fluorescence spectroscopies. The photophysical behaviors of the chlorins in liposomes like cellular membrane were compared with those obtained from chlorin-liposome systems delivered to Jurkat cells in order to select potent photosensitizers for the photodynamic treatment of cancer. The localization of the studied chlorins inside liposomes was found to depend strongly on the substituents of chlorins. Absorption spectra of chlorins embedded in DPPC-liposomes have been recorded in the temperature range of 20-70 deg. C. It is demonstrated that the location of the chlorin molecules depends on the phase state of the phospholipids. These observations are confirmed by the fluorescence lifetimes, singlet oxygen lifetimes and singlet oxygen quantum yields results

  17. Fluoridation of gaseous phase chlorinated hydrocarbons in presence of chromium oxide-based catalysts. Effect of doping substance addition; Fluoration d'hydrocarbures chlores en phase gazeuse en presence de catalyseurs a base d'oxyde de chrome. Effet de l'ajout de dopant

    Energy Technology Data Exchange (ETDEWEB)

    Loustaunau, A.

    2003-11-01

    The preparation of various hydro-fluorocarbons (HFC), like CF{sub 3}CH{sub 2}F, CF{sub 3}CHF{sub 2} and CH{sub 2}F{sub 2}, has been studied at temperatures of 380 deg. C and 250 deg. C in gaseous phase by catalytic fluoridation of the corresponding chlorinated hydrocarbons. The addition of doping substances like zinc, nickel or magnesium to fluorinated alumina supported chromium oxide-based catalysts, has been particularly examined in order to favour the main fluoridation reaction (by simple Cl/F exchange) with respect to secondary reactions (de-hydro-fluoridation and Deacon). Only the addition of small amounts of Zn (Zn/(Zn+Cr) = 0.15) allows to promote the fluoridation reaction and to inhibit the secondary reactions. This effect is enhanced when the molecule is less reactive and when the quantity of matter at the surface of the fluorinated alumina is low. Therefore, the promoting effect is more important in presence of CF{sub 3}CH{sub 2}Cl than in presence of CF{sub 3}CHCl{sub 2} and CH{sub 2}Cl{sub 2}. This positive effect of zinc may result from the formation of a mixed ZnCr{sub 2}O{sub 4} phase during the preparation of the catalyst (evidenced by X-ray photoelectron spectroscopy (XPS)) which may have modified the chemical properties of chromium atoms. Moreover, the XPS and electron microscopy characterizations indicate that the presence of zinc (contrary to nickel and magnesium) may allow a better dispersion of the active chromium atoms for Cl/F exchanges after fluoridation of the catalyst. Those may correspond to the presence of very fluorinated species, like 'Cr-F', and oxi-fluorinated like 'CrOF'. Thus, in the presence of a small amount of metals at the surface of the support, the formation of these different species is favoured. (J.S.)

  18. Natural Attenuation Mechanism and Capability of Chlorinated Hydrocarbons in Shallow Groundwater in a Study Area in Shanghai%上海某污染场地浅层地下水中氯代烃自然降解机制及能力研究

    Institute of Scientific and Technical Information of China (English)

    郭琳

    2013-01-01

    自然衰减修复技术(Natural Attenuation remedy)是目前控制浅层地下水氯代烃污染比较可行的技术之一,其能否成功应用的关键在于证实在天然条件下是否存在氯代烃生物降解可能性及生物降解程度是否能满足场地的修复目标.针对上海某污染场地的浅层地下水氯代烃污染在自然条件下生物降解的机制进行了探讨,并对该场地氯代烃污染自然衰减能力进行了定性评价,以及利用归一化方法计算了场地内1,1,1-三氯乙烷的生物降解速率常数为0.032a-1,说明浅层地下水中的1,1,1-三氯乙烷存在天然生物降解,但降解速率比较缓慢,可采用人工加强自然衰减的方式对该场地进行修复.%Natural Attenuation Remedy is an effective and feasible technology for controlling the shallow groundwater chlorinated hydrocarbons contamination,the key of this technology is to verify the existence of biological degradation under the natural conditions,and determine whether the degradation can meet the remediation target levet.The mechanism of natural attenuation in groundwater of a study area in Shanghai was discussed,and the capacity of natural attenuation was also evaluated qualitatively.The calculated biological degradation rate of l,l,l-trichloroethane of this site is 0.032 a-1,which indicated the sufficient evidence of natural attenuation,but the degradation velocity is relatively slow.The natural attenuation process can be enhanced by some artificial measures.

  19. Environmentally acceptable incineration of chlorinated chemical waste: review of theory and practice

    NARCIS (Netherlands)

    De Zeeuw, M.A.; Lemkowitz, S.M.

    1987-01-01

    Chlorinated hydrocarbons in the form of chemical waste, represent a threat to the environment and public health of the world. Their proper handling, removal and destruction is critical to long term safety. Increasingly strict government legislation is leading to an increase in the quantity of chlori

  20. Chlorine Analysis by Diode Laser Atomic Absorption Spectrometry

    Institute of Scientific and Technical Information of China (English)

    Joachim Koch; Aleksandr Zybin; Kay Niemax

    2000-01-01

    The general characteristics of Diode Laser Absorption Spectrometry (DLAAS) in low pressure plasmas particulary with respect to the detection of non-metals are comprehensively recapitulated and discussed. Furthermore, a detector, which is based on DLAAS in a microwave-induced low pressure plasma as an alternative technique for halogene-specific analysis of volatile compounds and polymeric matrices is described. The analytical capability of the technique is demonstrated on the chlorine-specific analysis of ablated polymer fragments as well as gas chromatographically separated hydrocarbons. Since the measurements were carried out by means of a balanced-heterodyne detection scheme, different technical noise contributions, such as laser excess and RAM noise could efficiently be suppressed and the registered absorption was limited only by the principal shot noise. Thus, in the case of the polymer analysis a chlorine-specific absolute detection limit of 10 pg could be achieved. Furthermore, fundamental investigations concerning the influence of hydrocarbons on the dissociation capability of the microwave induced plasma were performed. For this purpose, the carbon-, chlorine-and hydrogen-specific stoichiometry of the compounds were empirically determined. Deviations from the exspected proportions were found to be insignificant, implying the possibility of internal standardization relative to the response of a reference sample.

  1. Inactivation of Chironomid Larvae with Chlorine Dioxide and Chlorine

    Institute of Scientific and Technical Information of China (English)

    SUN Xin-bin; CUI Fu-yi

    2008-01-01

    Chironomid larvae propagate prolifically in eutrophic water body and they cannot be exterminated by conventional disinfection process.The inactivation effects of chlorine and chlorine dioxide on Chironomid larvae were investigated and some boundary values in practice were determined under conditions of various oxidant dosage,organic precursor concentration and pH value.In addition,removal effect of differmt pre-oxidation combined with coagulation process on Chironomid larvae in law water was evaluated.It was found that chlorine dioxide possessed better inactivation effect than chlorine.Complete inactivation of Chironomid larvae in raw water was resulted by 1.5mg/L of chlorine dioxide with 30min of contact time. Additionally,the ocgallic precursor concentration,pH value had little influence on the inactivation effect.The coagulation jar test showed that Chironomid larvae in the raw water could be completely ronxwed by chlorine dioxide pre-oxidation in combination with the omgulation process at chlorine dioxide dosage of 0.8 mg/L.

  2. Biodegradation of chlorinated hydrocarbons in a vapor phase reactor

    International Nuclear Information System (INIS)

    A bench scale gas lift loop reactor was constructed to evaluate the feasibility of trichloroethylene (TCE) degradative microorganisms being used to treat TCE contaminated air. Two different microorganisms were used as biocatalysts in this reactor. After proper operating conditions were established for use of this reactor/biocatalyst combination, both microorganisms could degrade 95% of inlet TCE at air flow rates of up to 3% of the total reactor volume per minute. TCE concentrations of between 300 μg/L (60ppmv) and 3000 μg/L (600 ppmv) were degraded with 95% or better efficiency. Preliminary economic evaluations suggest that bioremediation may be the low cost alternative for treating certain TCE contaminated air streams and field trials of a scaled-up reactor system based on this technology are currently underway

  3. Ultrafast Third-Order Nonlinear Optical Spectroscopy of Chlorinated Hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Napoleon Thantu; Robert S. Schley

    2003-09-01

    Time-resolved Raman induced Kerr effect spectroscopy in the optical heterodyne detection configuration has been employed to investigate intermolecular, intramolecular, and reorientational dynamics in neat trichloroethylene (TCE). The reorientation time constant is directly measured from the time-resolved data, while Fourier transformation of the time-resolved data yields the intermolecular and intramolecular vibrational spectrum. Use of ultrashort, femtosecond pulses enables excitation of depolarized Raman-active transitions between 1 and 500 cm-1. The intramolecular vibrations have been identified using a previous assignment. The limitations imposed by the laser and detector noise, and other nonlinear optical processes that are manifest at high pulse intensities, on the use of this time-domain technique for performing chemical species detection are discussed using carbon tetrachloride as an example.

  4. Pesticide Instrumental Analysis

    International Nuclear Information System (INIS)

    This workshop was the evaluation of the pesticides impact on the vegetable matrix with the purpose to determine the analysis by GC / M S. The working material were lettuce matrix, chard and a mix of green leaves and pesticides.

  5. Pesticides and Pregnancy

    Science.gov (United States)

    Pesticides and Pregnancy In every pregnancy, a woman starts out with a 3-5% chance of having ... risk. This sheet talks about whether exposure to pesticides may increase the risk for birth defects over ...

  6. Pesticide Product Label System

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Pesticide Product Label System (PPLS) provides a collection of pesticide product labels (Adobe PDF format) that have been approved by EPA under Section 3 of the...

  7. Pesticide exposure - Indian scene

    International Nuclear Information System (INIS)

    Use of pesticides in India began in 1948 when DDT was imported for malaria control and BHC for locust control. India started pesticide production with manufacturing plant for DDT and benzene hexachloride (BHC) (HCH) in the year 1952. In 1958, India was producing over 5000 metric tonnes of pesticides. Currently, there are approximately 145 pesticides registered for use, and production has increased to approximately 85,000 metric tonnes. Rampant use of these chemicals has given rise to several short-term and long-term adverse effects of these chemicals. The first report of poisoning due to pesticides in India came from Kerala in 1958 where, over 100 people died after consuming wheat flour contaminated with parathion. Subsequently several cases of pesticide-poisoning including the Bhopal disaster have been reported. Despite the fact that the consumption of pesticides in India is still very low, about 0.5 kg/ha of pesticides against 6.60 and 12.0 kg/ha in Korea and Japan, respectively, there has been a widespread contamination of food commodities with pesticide residues, basically due to non-judicious use of pesticides. In India, 51% of food commodities are contaminated with pesticide residues and out of these, 20% have pesticides residues above the maximum residue level values on a worldwide basis. It has been observed that their long-term, low-dose exposure are increasingly linked to human health effects such as immune-suppression, hormone disruption, diminished intelligence, reproductive abnormalities, and cancer. In this light, problems of pesticide safety, regulation of pesticide use, use of biotechnology, and biopesticides, and use of pesticides obtained from natural plant sources such as neem extracts are some of the future strategies for minimizing human exposure to pesticides

  8. Emissions from Open burning of Used Agricultural Pesticide Containers

    Science.gov (United States)

    Emissions from simulated open burning of used agricultural pesticide containers were sampled for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/PCDFs), polycyclic aromatic hydrocarbon compounds (PAHs), and particle matter (PM10 and PM2.5). Clean high density polyethyl...

  9. Grundfoss: Chlorination of Swimming Pools

    DEFF Research Database (Denmark)

    Hjorth, Poul G.; Hogan, John; Andreassen, Viggo

    1998-01-01

    Grundfos asked for a model, describing the problem of mixing chemicals, being dosed into water systems, to be developed. The application of the model should be dedicated to dosing aqueous solution of chlorine into swimming pools.......Grundfos asked for a model, describing the problem of mixing chemicals, being dosed into water systems, to be developed. The application of the model should be dedicated to dosing aqueous solution of chlorine into swimming pools....

  10. Transformation of iopamidol during chlorination.

    Science.gov (United States)

    Wendel, Friedrich M; Lütke Eversloh, Christian; Machek, Edward J; Duirk, Stephen E; Plewa, Michael J; Richardson, Susan D; Ternes, Thomas A

    2014-11-01

    The transformation of the iodinated X-ray contrast media (ICM) iopamidol, iopromide, iohexol, iomeprol, and diatrizoate was examined in purified water over the pH range from 6.5 to 8.5 in the presence of sodium hypochlorite, monochloramine, and chlorine dioxide. In the presence of aqueous chlorine, only iopamidol was transformed. All other ICM did not show significant reactivity, regardless of the oxidant used. Chlorination of iopamidol followed a second order reaction, with an observed rate constant of up to 0.87 M(-1) s(-1) (±0.021 M(-1) s(-1)) at pH 8.5. The hypochlorite anion was identified to be the reactive chlorine species. Iodine was released during the transformation of iopamidol, and was mainly oxidized to iodate. Only a small percentage (less than 2% after 24 h) was transformed to known organic iodinated disinfection byproducts (DBPs) of low molecular weight. Some of the iodine was still present in high-molecular weight DBPs. The chemical structures of these DBPs were elucidated via MSn fragmentation and NMR. Side chain cleavage was observed as well as the exchange of iodine by chlorine. An overall transformation pathway was proposed for the degradation of iopamidol. CHO cell chronic cytotoxicity tests indicate that chlorination of iopamidol generates a toxic mixture of high molecular weight DBPs (LC50 332 ng/μL).

  11. EFFECTS OF OZONE, CHLORINE DIOXIDE, CHLORINE, AND MONOCHLORAMINE ON CRYTOSPORIDIUM PARVUM OOCYST VIABILITY

    Science.gov (United States)

    Purified Cryptosporiodium parvum oocysts were exposed to ozone, chlorine dioxide, chlorine, and monochloramine. Excystation and mouse infectivity were compareatively evaluated to assess oocyst viability. Ozone and chlorine dioxide more effectively inactivated oocysts than chlor...

  12. Kinetic study of neodymium oxide chlorination with gaseous chlorine

    Energy Technology Data Exchange (ETDEWEB)

    Bosco, Marta V., E-mail: marta.bosco@cab.cnea.gov.ar [Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina); Fouga, Gaston G. [Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina); Complejo Tecnologico Pilcaniyeu, Comision Nacional de Energia Atomica, Avenida Bustillo 9500, CP 8400 San Carlos de Bariloche (Argentina); Bohe, Ana E. [Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina); Complejo Tecnologico Pilcaniyeu, Comision Nacional de Energia Atomica, Avenida Bustillo 9500, CP 8400 San Carlos de Bariloche (Argentina); Centro Regional Universitario Bariloche, Universidad Nacional del Comahue, CP 8400 San Carlos de Bariloche (Argentina)

    2012-07-20

    Highlights: Black-Right-Pointing-Pointer We analyze the kinetics of the neodymium oxide chlorination reactions. Black-Right-Pointing-Pointer For temperatures below 425 Degree-Sign C the system is under chemical control. Black-Right-Pointing-Pointer The formation of oxychloride progresses through a nucleation and growth mechanism. Black-Right-Pointing-Pointer A reaction order of 0.40 with respect to chlorine partial pressure was determined. Black-Right-Pointing-Pointer An activation energy of 161 {+-} 4 kJ mol{sup -1} was determined. - Abstract: The kinetics of the chlorination of neodymium oxide has been investigated by thermogravimetry between 312 Degree-Sign C and 475 Degree-Sign C, and for partial pressures of chlorine ranging from 10 kPa to 50 kPa. The starting temperature for the reaction of neodymium oxide with chlorine was determined to be about 250 Degree-Sign C, leading to neodymium oxychloride as product. The results showed that, for temperatures below 425 Degree-Sign C, the system is under chemical control and the formation of the oxychloride progresses through a nucleation and growth mechanism. The influence of chlorine mass transport through the bulk gas phase and through the boundary layer on the overall reaction rate was analyzed. In the absence of these two mass-transfer steps, a reaction order of 0.39 with respect to chlorine partial pressure, and an activation energy of 161 {+-} 4 kJ mol{sup -1} were determined. A complete rate equation has been successfully developed.

  13. Rapid sample preparation and fast GC-MS/MS for the analysis of pesticides and environmental contaminants in fish

    Science.gov (United States)

    A rapid high-throughput analytical method for the simultaneous determination of pesticides and environmental contaminants, including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and flame retardants (FRs) in fish was developed and ...

  14. Environmental applications of the electron-capture detector - pesticides

    International Nuclear Information System (INIS)

    Employing ECDs for the routine analysis of pesticide residues and other chlorinated organics in biological and environmental substrates usually involves quite a few trade-offs between speed, reliability and sensitivity. Various contaminants including bleed from the septum and liquid phase, oxygen from the atmosphere or carrier gas and excessive amounts of co-extractives markedly affect linearity and detection limits. Also the choice of GC column and amount of preceding clean-up of samples can drastically influence the lifetime (and intervals between rejuvenation) of the foil. Similarly, the choice of derivatization reaction in pesticide residue analysis is crucial since it is utilized for a variety of reasons, but primarily to enhance detection, allow determination of active hydrogen-containing pesticides or their metabolites and for the confirmation of identity. These factors are discussed. (Auth.)

  15. Field-usable portable analyzer for chlorinated organic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Buttner, W.J.; Penrose, W.R.; Stetter, J.R. [Transducer Research, Inc., Naperville, IL (United States)

    1995-10-01

    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 handportable 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.

  16. Pesticides and oncogenic modulation.

    Science.gov (United States)

    Vakonaki, Elena; Androutsopoulos, Vasilis P; Liesivuori, Jyrki; Tsatsakis, Aristidis M; Spandidos, Demetrios A

    2013-05-10

    Pesticides constitute a diverse class of chemicals used for the protection of agricultural products. Several lines of evidence demonstrate that organochlorine and organophosphate pesticides can cause malignant transformation of cells in in vitro and in vivo models. In the current minireview a comprehensive summary of recent in vitro findings is presented along with data reported from human population studies, regarding the impact of pesticide exposure on activation or dysregulation of oncogenes and tumor suppressor genes. Substantial mechanistic work suggests that pesticides are capable of inducing mutations in oncogenes and increase their transcriptional expression in vitro, whereas human population studies indicate associations between pesticide exposure levels and mutation occurrence in cancer-related genes. Further work is required to fully explore the exact mechanisms by which pesticide exposure affects the integrity and normal function of oncogenes and tumor suppressor genes in human populations.

  17. The hydrocarbon sphere

    Energy Technology Data Exchange (ETDEWEB)

    Mandev, P.

    1984-01-01

    The hydrocarbon sphere is understood to be the area in which hydrocarbon compounds are available. It is believed that the lower boundary on the hydrocarbon sphere is most probably located at a depth where the predominant temperatures aid in the destruction of hydrocarbons (300 to 400 degrees centigrade). The upper limit on the hydrocarbon sphere obviously occurs at the earth's surface, where hydrocarbons oxidize to H20 and CO2. Within these ranges, the occurrence of the hydrocarbon sphere may vary from the first few hundred meters to 15 kilometers or more. The hydrocarbon sphere is divided into the external (mantle) sphere in which the primary gas, oil and solid hydrocarbon fields are located, and the internal (metamorphic) sphere containing primarily noncommercial accumulations of hydrocarbon gases and solid carbon containing compounds (anthraxilite, shungite, graphite, etc.) based on the nature and scale of hydrocarbon compound concentrations (natural gas, oil, maltha, asphalt, asphaltite, etc.).

  18. Control of Pesticides 2000

    DEFF Research Database (Denmark)

    Krongaard, T.; Petersen, K. K.; Christoffersen, C.

    Three different groups of products covered by the pesticide regulation have been included in the 2000 analytical chemical authority control: 1) herbicides containing aclonifen, clopyralid, dicamba, quinoclamine, bromoxynil, ioxynil, simazine, and terbuthylazine. 2) Fungicides containing fenpropidin......, fluazinam, and kresoxim-methyl, and among insecticides containing fenazaquin. Thus, all the eighteen analysed samples of these pesticides complied with the accepted tolerances with respect to content of active ingredients set by the Danish regulation of pesticides. The only product containing buprofezin...

  19. Pesticides and childhood cancers.

    OpenAIRE

    Daniels, J L; Olshan, A.F.; Savitz, D A

    1997-01-01

    To evaluate the possible association between pesticides and the risk of childhood cancers, epidemiologic studies published between 1970 and 1996 were critically reviewed. Thirty-one studies investigated whether occupational or residential exposure to pesticides by either parents or children was related to increased risk of childhood cancer. In general, the reported relative risk estimates were modest. Risk estimates appeared to be stronger when pesticide exposure was measured in more detail. ...

  20. Pesticides (Environmental Health Student Portal)

    Science.gov (United States)

    ... Pesticides Climate Change Climate Change Home What is Climate Change ... Pesticides The Basics Pesticides are substances we use to control or kill pests. Pests can be weeds, insects, rodents, or bacteria — anything we don’t want ...

  1. Petroleum Hydrocarbons, Chlorinated Hydrocarbons, and Metal in Soils and Sediments of Quivira National Wildlife Refuge, 1989

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Numerous oil production facilities were in place when Quivira NWR was purchased, and oil production has continued and some new production facilities have been...

  2. Effects of ozone, chlorine dioxide, chlorine, and monochloramine on Cryptosporidium parvum oocyst viability.

    OpenAIRE

    Korich, D G; Mead, J R; Madore, M S; Sinclair, N. A.; Sterling, C R

    1990-01-01

    Purified Cryptosporidium parvum oocysts were exposed to ozone, chlorine dioxide, chlorine, and monochloramine. Excystation and mouse infectivity were comparatively evaluated to assess oocyst viability. Ozone and chlorine dioxide more effectively inactivated oocysts than chlorine and monochloramine did. Greater than 90% inactivation as measured by infectivity was achieved by treating oocysts with 1 ppm of ozone (1 mg/liter) for 5 min. Exposure to 1.3 ppm of chlorine dioxide yielded 90% inactiv...

  3. Pesticide Product Information System (PPIS)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Pesticide Product Information System contains information concerning all pesticide products registered in the United States. It includes registrant name and...

  4. Removal of Chlorinated Chemicals in H2 Feedstock Using Modified Activated Carbon

    Directory of Open Access Journals (Sweden)

    Prapaporn Luekittisup

    2015-01-01

    Full Text Available Activated carbon (GAC was impregnated by sodium and used as adsorbent to remove chlorinated hydrocarbon (CHC gases contaminated in H2 feedstock. The adsorption was carried out in a continuous packed-bed column under the weight hourly space velocity range of 0.8–1.0 hr−1. The adsorption capacity was evaluated via the breakthrough curves. This modified GAC potentially adsorbed HCl and VCM of 0.0681 gHCl/gadsorbent and 0.0026 gVCM/gadsorbent, respectively. It showed higher adsorption capacity than SiO2 and Al2O3 balls for both organic and inorganic CHCs removal. In addition, the kinetic adsorption of chlorinated hydrocarbons on modified GAC fit well with Yoon-Nelson model.

  5. Pesticide Sector Performed Well

    Institute of Scientific and Technical Information of China (English)

    Wang Lvxian

    2007-01-01

    @@ 1 Further output growth in the first half of 2007 According to data from the National Bureau of Statistics of China, the output of pesticides (usually refering to pure pesticide technical) in China was 856 thousand tons in the first half of 2007, an increase of 25.6% over the same period of 2006.

  6. Pesticider 2 i overfladevand

    DEFF Research Database (Denmark)

    Nyeland, B.; Kvamm, B. L.

    DMU har den 29. september 1999 afholdt en metodeafprøvning: Pesticider 2 i overfladevand. Der var tilmeldt 17 danske og udenlandske laboratorier i metodeafprøvningen. Prøvningen omfattede 32 pesticider i overfladevand fra en sjællandsk sø. Koncentrationsniveauet for hver komponent var på 0,025 - 0...

  7. Pesticides in Ground Water

    DEFF Research Database (Denmark)

    Bjerg, Poul Løgstrup

    1996-01-01

    Review af: Jack E. Barbash & Elizabeth A. Resek (1996). Pesticides in Ground Water. Distribution trends and governing factors. Ann Arbor Press, Inc. Chelsea, Michigan. pp 588.......Review af: Jack E. Barbash & Elizabeth A. Resek (1996). Pesticides in Ground Water. Distribution trends and governing factors. Ann Arbor Press, Inc. Chelsea, Michigan. pp 588....

  8. Screening Pesticides for Neuropathogenicity

    OpenAIRE

    Doherty, John D.

    2006-01-01

    Pesticides are routinely screened in studies that follow specific guidelines for possible neuropathogenicity in laboratory animals. These tests will detect chemicals that are by themselves strong inducers of neuropathogenesis if the tested strain is susceptible relative to the time of administration and methodology of assessment. Organophosphate induced delayed neuropathy (OPIDN) is the only known human neurodegenerative disease associated with pesticides and the existing...

  9. Neurotoxicity of pesticides.

    Science.gov (United States)

    Keifer, Matthew C; Firestone, Jordan

    2007-01-01

    Several pesticides such as organophosphates, carbamates and the organochlorine pesticides directly target nervous tissue as their mechanism of toxicity. In several others, such as the fumigants, the nervous system is affected by toxicological mechanisms that diffusely affect most or all tissues in the body. Both the central and peripheral nervous system are involved in the acute toxidromes of many pesticides resulting in acute short-term effects. There is strong human epidemiological evidence for persistent nervous system damage following acute intoxication with several important pesticide groups such as organophosphates and certain fumigants. However, whether persistent nervous system damage follows chronic low-level exposure to pesticides in adults (particularly organophosphpates), and whether in utero and/or early childhood exposure leads to persistent nervous system damage, is a subject of study at present. Parkinson's Disease, one of the most common chronic central nervous system diseases, has been linked to pesticide exposure in some studies, but other studies have failed to find an association. Several new pesticidal chemicals such as the neo-nicotinoids and fipronil have central nervous system effects, but only case reports are available to date on acute human intoxications with several of these. Little data are yet available on whether long-term effects result from these chemicals. Several ongoing or recently completed studies should add valuable insight into the effects of pesticides on the human nervous system particularly the effect of low-dose, chronic exposure both in adults and children.

  10. Bioremediation of petroleum hydrocarbons in soil environments

    International Nuclear Information System (INIS)

    The bioremediation of petroleum hydrocarbons in soil environments was reviewed via a literature survey and discussions with workers in relevant disciplines. The impacts of hydrocarbons on soil are discussed along with a range of methods available to assist in their decomposition by soil microorganisms. The range of petroleum-based materials considered includes conventional and synthetic crude oils, refined oils, sludges, asphalts and bitumens, drilling mud residues, creosote tars, and some pesticides. The degradability of hydrocarbons largely depends upon their aqueous solubility and their adsorption on soil surfaces and, therefore, is related to their molecular structures. The ease of decomposition decreases with increasing complexity of structure, in the order aliphatics > aromatics > heterocyclics and asphaltenes (most recalcitrant). Most soils contain an adequate population of microorganisms and hence bioaugmentation may only be needed in special circumstances. Decomposition is fastest in soils where the hydrocarbon loading rate, aeration, nutrition, moisture, and pH are all optimized. At spill sites there is little control over the application rate, although containment measures can assist in either limiting contamination or distributing it more evenly. The enhancement of bioremediation is discussed in light of all these factors. Other techniques such as enhanced aeration, hydrocarbon decomposition by anaerobic processes, surfactants, and burning are also discussed. 211 refs., 11 figs., 10 tabs

  11. Raman characteristics of hydrocarbon and hydrocarbon inclusions

    Institute of Scientific and Technical Information of China (English)

    ZHANG Nai; TIAN ZuoJi; LENG YingYing; WANG HuiTong; SONG FuQing; MENG JianHua

    2007-01-01

    The Raman spectrograms of hydrocarbon standard samples show that: (1) the Raman spectrogram of normal paraffin has very strong peaks of methyl and methylene (from 2700 cm-1 to 2970 cm-1); (2)branch methyl has the particular peak of 748 cm-1±; (3) six cyclic has the particular peak of 804 cm-1±; (4)phenyl has two particular peaks of 988 cm-1± and 3058 cm-1± and the 988 cm-1± peak is stronger than the 3058 cm-1± peak; and (5) hexene has three alkenyl spectrum peaks of 1294 cm-1±, 1635 cm-1± and 2996 cm-1±, with the 1635 cm-1± peak being the strongest, showing that the number of carbon in hydrocarbon does not affect its Raman spectrogram, and the hydrocarbon molecular structure and base groups affect its Raman spectrogram, the same hydrocarbons (such as normal paraffin) have the same Raman spectrogram; the types (such as CH4, C2H6, C3H8) and the content of hydrocarbon in oil inclusions are not estimated by their characteristic Raman peaks. According to the Raman spectrograms of hydrocarbon compositions, the Raman spectrogram of hydrocarbon inclusion can be divided into five types: saturated hydrocarbon Raman spectrogram, fluoresce Raman spectrogram, saturated hydrocarbon bitumen Raman spectrogram, bitumen Raman spectrogram, and ethane Raman spectrogram.And according to the characteristics of Raman spectrogram, hydrocarbon inclusions can be divided into five types: saturated hydrocarbon inclusion, less saturated hydrocarbon (oil or gas) inclusion,saturated hydrocarbon bitumen inclusion, bitumen inclusion, and methane water inclusion.

  12. Raman characteristics of hydrocarbon and hydrocarbon inclusions

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The Raman spectrograms of hydrocarbon standard samples show that: (1) the Raman spectrogram of normal paraffin has very strong peaks of methyl and methylene (from 2700 cm-1 to 2970 cm-1); (2) branch methyl has the particular peak of 748 cm-1±; (3) six cyclic has the particular peak of 804 cm-1±; (4) phenyl has two particular peaks of 988 cm-1± and 3058 cm-1± and the 988 cm-1± peak is stronger than the 3058 cm-1± peak; and (5) hexene has three alkenyl spectrum peaks of 1294 cm-1±, 1635 cm-1± and 2996 cm-1±, with the 1635 cm-1± peak being the strongest, showing that the number of carbon in hy-drocarbon does not affect its Raman spectrogram, and the hydrocarbon molecular structure and base groups affect its Raman spectrogram, the same hydrocarbons (such as normal paraffin) have the same Raman spectrogram; the types (such as CH4, C2H6, C3H8) and the content of hydrocarbon in oil inclu-sions are not estimated by their characteristic Raman peaks. According to the Raman spectrograms of hydrocarbon compositions, the Raman spectrogram of hydrocarbon inclusion can be divided into five types: saturated hydrocarbon Raman spectrogram, fluoresce Raman spectrogram, saturated hydro-carbon bitumen Raman spectrogram, bitumen Raman spectrogram, and ethane Raman spectrogram. And according to the characteristics of Raman spectrogram, hydrocarbon inclusions can be divided into five types: saturated hydrocarbon inclusion, less saturated hydrocarbon (oil or gas) inclusion, saturated hydrocarbon bitumen inclusion, bitumen inclusion, and methane water inclusion.

  13. Control of Pesticides 2001

    DEFF Research Database (Denmark)

    Krongaard, T.; Petersen, K. K.; Christoffersen, C.

    The analytical chemical authority control on pesticide products on the Danish market performed in 2001 is reported. Samples of selected groups of pesticides have been collected from the market and analysed to verify whether the actual contents of the respective active ingredients in the products...... comply with the label-claimed content. The tolerance of deviation from the label-claimed content of active ingredient is set by the Danish pesticide regulation. Three different groups of products covered by the pesticide regulation have been included in the 2001 analytical chemical authority control: 1....... Satisfactory results were found among herbicides containing pendimethalin and methabenzthiazuron, among fungicides containing azaconazole, tolylfluanid, propamocarb and cyprodinil, and among insecticides containing amitraz, phosalone and diflubenzuron. Thus, the twelve analysed samples of these pesticides...

  14. PESTICIDES: BENEFITS AND HAZARDS

    Directory of Open Access Journals (Sweden)

    Ivan Maksymiv

    2015-05-01

    Full Text Available Pesticides are an integral part of modern life used to prevent growth of unwanted living  organisms. Despite the fact that scientific statements coming from many toxicological works provide indication on the low risk of the pesticides and their residues, the community especially last years is deeply concerned about massive application of pesticides in diverse fields. Therefore evaluation of hazard risks particularly in long term perspective is very important. In the fact there are at least two clearly different approaches for evaluation of pesticide using: the first one is defined as an objective or probabilistic risk assessment, while the second one is the potential economic and agriculture benefits. Therefore, in this review the author has considered scientifically based assessment of positive and negative effects of pesticide application and discusses possible approaches to find balance between them.

  15. Effects of chlorine content and position of chlorinated phenols on their oxidation kinetics by potassium permanganate

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Chlorine content and position of chlorinated phenols have many significant effects on the reactivity of oxido-reduction. The effects of chlorine content and position of chlorinated phenols on their oxidation kinetics by potassium permanganate were evaluated through different kinetics studies. Since chlorine was an electron withdrawing atom, the substitution of chlorine on the aromatic ring decreased the oxidation rate constant by σ-electron withdrawing conductive effect; at the same time, the substitution of chlorine at ortho or para position on the aromatic ring increased the oxidation rate constant by π-electron donating conjugative effect, and the conjugative effect could counteract the negative impact of the conductive effect to some extent. On the other hand, the substitution of chlorine at ortho position on the aromatic ring decreased the oxidation rate constant by steric hindrance effect. The oxidation rate constants of phenol and chlorinated phenols studied decreased as follow order: 4-chlorophenol>2,4-dichlorophenol>phenol>2,6-dichlorophenol.

  16. A gas/liquid chromatographic-mass spectrometric method for the rapid screening of 250 pesticides in aqueous matrices

    Energy Technology Data Exchange (ETDEWEB)

    Chandramouli, B.; Harvan, D.; Brittain, S.; Hass, R. [Eno River Labs, LLC. Durham, NC (United States)

    2004-09-15

    Pesticide residues in food present a potentially serious and significant cause for concern. Many pesticides have been associated with significant health effects to the nervous and endocrine systems and some have been deemed carcinogenic. There are many well-established techniques for pesticide analysis. However, commercial pesticide methods have traditionally only been available for specific pesticide families, such as chlorinated pesticides or herbicides, and at detection limits ranging from 0.05 ppb to 1 ppm in aqueous matrices. Techniques that can quickly screen for the presence/absence of pesticide residues in food matrices are critical in ensuring the safety of food and water. This paper outlines a combined Gas Chromatographic-High Resolution Mass Spectrometric (GC-HRMS) and Liquid Chromatographic Tandem Mass Spectrometric (LC-MS/MS) screening assay for 250 pesticides that was developed for use in water, and soda samples at screening levels ranging from 0.1-5 ppb. The pesticides selected have been identified by the European Union as being of concern and the target of possible legislation. The list encompasses a variety of pesticide classes and compound groupings.

  17. Use of isotopic tracers in pesticide and environmental contamination research

    International Nuclear Information System (INIS)

    The era of synthetic organic pesticides, starting with DDT and the herbicide 2,4-D about 1940, coincides with that of rapid advances in radiotracer applications. This is indeed fortunate since isotopic experiments are an essential step in evaluating each new pesticide and in continually reassessing older compounds for safety and most efficient utilization. This research is carried out in all developed nations with important supplementation on local problems or use conditions from investigations in the developing countries. Several slides will help illustrate the sequence of studies for establishing the disposition and fate of pesticides and other environmental contaminants.It is clear that very little of the pesticide ever contacts the pest. Pesticide chemicals are generally applied at dosages of 0.2 to 2 kilogram per hectare from one to five or more times per crop season. Less than 0.01% of an insecticide is absorbed or ingested by the pest insect. The remaining amount, more than 99.99%, is an environmental contaminant, a portion of which is a potential residue in food, feed and fibre. Isotopic research is critical in understanding or solving several aspects of the problem. The isotopic label is introduced into the chemical by synthesis in a commercial or university laboratory or in a national or regional atomic research centre. The most common radioisotopes used are tritium, 14carbon, 32phosphorus, 35sulphur and 36chlorine. Stable isotopes are becoming increasingly important in pesticide research, particularly carbon 13, nitrogen 15 and oxygen 18. The initial studies usually involve administration of the 14 carbon-labelled pesticide to rats, which are then held in metabolism cages that allow separate collection of expired gases, urine and faeces. The products in the excreta are identified by various chromatographic and spectroscopic techniques. The persistence of the chemical and its metabolites in various tissues is also determined to make sure that the material

  18. Chlorine signal attenuation in concrete.

    Science.gov (United States)

    Naqvi, A A; Maslehuddin, M; ur-Rehman, Khateeb; Al-Amoudi, O S B

    2015-11-01

    The intensity of prompt gamma-ray was measured at various depths from chlorine-contaminated silica fume (SF) concrete slab concrete specimens using portable neutron generator-based prompt gamma-ray setup. The intensity of 6.11MeV chloride gamma-rays was measured from the chloride contaminated slab at distance of 15.25, 20.25, 25.25, 30.25 and 35.25cm from neutron target in a SF cement concrete slab specimens. Due to attenuation of thermal neutron flux and emitted gamma-ray intensity in SF cement concrete at various depths, the measured intensity of chlorine gamma-rays decreases non-linearly with increasing depth in concrete. A good agreement was noted between the experimental results and the results of Monte Carlo simulation. This study has provided useful experimental data for evaluating the chloride contamination in the SF concrete utilizing gamma-ray attenuation method.

  19. Chlorine isotope investigation of natural attenuation of trichloroethene in an aerobic aquifer

    International Nuclear Information System (INIS)

    Natural attenuation of chlorinated aliphatic hydrocarbons (CAHs) can be an important mechanism for groundwater remediation. It is difficult to determine the effectiveness of natural CAH attenuation from chemical analyses of groundwater samples because mixing, dispersion, and secondary reactions can mask the chemical evidence of attenuation. In this paper, the authors explore the application of stable chlorine isotope ratio measurements as a new tool for evaluating natural attenuation of CAHs. They report stable isotope ratios of chlorine in both trichloroethene (TCE) and inorganic chloride in groundwater from an aerobic aquifer beneath an extensively contaminated industrial site, the Paducah Gaseous Diffusion Plant in western Kentucky. Variations in the concentrations and chlorine isotope ratios of TCE and chloride in the groundwater are consistent with those expected from natural attenuation. These data support a model in which partial TCE degradation occurred in relatively impermeable, clay-rich sediments above the aquifer, and little or no further degradation of TCE occurred within the aquifer. A record of changing conditions within the TCE source area can be inferred from the spatial variation of chlorine isotope ratios for TCE and chloride within the plume

  20. The effect of chlorine and combined chlorine/UV treatment on coliphages in drinking water disinfection.

    Science.gov (United States)

    Zyara, Alyaa M; Torvinen, Eila; Veijalainen, Anna-Maria; Heinonen-Tanski, Helvi

    2016-08-01

    Chlorine disinfection is a globally used method to ensure the safety of drinking water. However, it has not always been successful against viruses and, therefore, it is important to find new methods to disinfect water. Seventeen different coliphages were isolated from the treated municipal wastewater. These coliphages and MS2 were treated with different dosages of chlorine in drinking water, and a combined chlorine/ultraviolet irradiation treatment for the chlorine-resistant coliphages. Chlorine disinfection with 0.3-0.5 mg/L total chlorine (free Cl-dosage 0.12-0.21 mg/L) for 10 min achieved 2.5-5.7 Log10-reductions for 11 sensitive coliphages. The six most resistant coliphages showed no reduction with these chlorine concentrations. MS2 was intermediate in chlorine resistance, and thus it is not a good indicator for viruses in chlorine disinfection. In the combined treatment total chlorine of 0.05-0.25 mg/L (free Cl-dosage 0.02-0.08 mg/L) and ultraviolet irradiation (14-22 mWs/cm(2)) were more effective than chlorine alone, and 3-5 Log10-reductions were achieved for the chlorine-resistant strains. The chlorination efficiency could be increased by higher dosages and longer contact times, but this could increase the formation of disinfection by-products. Therefore, the combination treatment is a recommended disinfection method.

  1. Treatability study of pesticide-based industrial wastewater.

    Science.gov (United States)

    Shah, Kinnari; Chauhan, L I; Galgale, A D

    2012-10-01

    This paper finds out appropriate treatment methods for wastewater of an Organophosphorus viz, chloropyrifos pesticide manufacturing industry. The characterization of wastewater generated during trial production of chloropyrifos was carried out. Based on the characterization of wastewater, various treatability studies were conducted. The most desirable results were obtained with treatment scheme employing acidification, chlorination with NaOCl, suspended growth biological treatment, chemical precipitation for phosphorous removal and activated carbon treatment. Acidification of wastewater helps in by-product recovery as well as reduction in COD upto 36.26%. Chlorination followed by biological treatment was found to be effective to reduce the COD level by 62.06%. To comply with permissible limits prescribed by Effluent Channel Project Ltd.(ECPL)* and Gujarat Pollution Control Board (GPCB) for discharge of industrial effluent into channel, further treatment in the form of chemical precipitation (for phosphorous removal) and granular activated carbon is suggested. PMID:25151721

  2. Two-phase ozonation of chlorinated organics

    International Nuclear Information System (INIS)

    In the last few years the amount of research being conducted in the field of single-phase ozonation has grown extensively. However, traditional aqueous-phase ozonation systems are limited by a lack of selective oxidation potential, low ozone solubility in water, and slow intermediate decomposition rates. Furthermore, ozone may decompose before it can be utilized for pollutant destruction since ozone can be highly unstable in aqueous solutions. Naturally occurring compounds such as NaHCO3 also affect ozone reactions by inhibiting the formation of OH-free radicals. To compensate for these factors, excess ozone is typically supplied to a reactor. Since ozone generation requires considerable electric power consumption (16 - 24 kWh/kg of O3), attempts to enhance the ozone utilization rate and stability should lead to more efficient application of this process to hazardous waste treatment. To improve the process, ozonation may be more efficiently carried out in a two-phase system consisting of an inert solvent (saturated with O3) contacted with an aqueous phase containing pollutants. The non-aqueous phase must meet the following criteria: (1) non-toxic, (2) very low vapor pressure, (3) high density (for ease of separation), (4) complete insolubility in water, (5) reusability, (6) selective pollutant extractability, (7) high oxidant solubility, and (8) extended O3 stability. Previously published studies (1) have indicated that a number of fluorinated hydrocarbon compounds fit these criteria. For this project, FC40 (a product of 3M Co.) was chosen due to its low vapor pressure (3 mm Hg) and high specific gravity (1.9). The primary advantages of the FC40 solvent are that it is non-toxic, reusable, has an ozone solubility 10 times that of water, and that 85 % of the ozone remains in the solvent even after 2 hours. This novel two-phase process has been utilized to study the rapid destruction of organic chlorine compounds and organic mixtures

  3. The Danish Pesticide Tax

    DEFF Research Database (Denmark)

    Pedersen, Anders Branth; Nielsen, Helle Ørsted; Andersen, Mikael Skou

    2015-01-01

    This case study analyses the effects of the Danish pesticide tax (1996-2013) on agriculture which was introduced as an ad valorem tax in 1996, doubled in 1998, and redesigned in 2013 as a tax based on the toxicity of the pesticides. The Danish pesticide taxes probably represent the world’s highest...... pesticide taxes on agriculture, which makes it interesting to analyze how effective they have been. Here the effects of the ad valorem tax (1996-2013) are analyzed. The case study demonstrates the challenges of choosing an optimal tax design in a complex political setting where, additionally, not all...... individuals in the target group necessarily react to the economic incentives as predicted by economic modeling. It also demonstrates that a small first green-tax-step over time might develop into a better tax design....

  4. Pesticide-Exposure Matrix

    Science.gov (United States)

    The "Pesticide-exposure Matrix" was developed to help epidemiologists and other researchers identify the active ingredients to which people were likely exposed when their homes and gardens were treated for pests in past years.

  5. Pesticide Registration Information System

    Data.gov (United States)

    U.S. Environmental Protection Agency — PRISM provides an integrated, web portal for all pesticide related data, communications, registrations and transactions for OPP and its stakeholders, partners and...

  6. Study of pesticides removal by processes used in Spain to produce drinking water; Eliminacion de plaguicidas mediante procesos utilizados en Espana para la produccion de agua potable

    Energy Technology Data Exchange (ETDEWEB)

    Ormand, M. P.; Claver, A.; Miguel, N.; Ovelleiro, J. L.

    2007-07-01

    The aim of this research work is study the effectiveness of treatments habitually used in drinking water plants in plants to remove 44 pesticides detected systematically in Ebro river basin Applied techniques are: pre oxidation by chlorine or ozone, chemical precipitation with aluminium sulphate and activated carbon adsorption. The intensive treatment (preoxidation, coagulation.flocculation and activated carbon adsorption) is a few less effective with chlorine than with ozone although both treatments achieve average removal yields of studied pesticides high, about 90%. (Author) 35 refs.

  7. Fracturing graphene by chlorination: a theoretical viewpoint

    OpenAIRE

    Ijäs, M.; Havu, P.; Harju, A.

    2012-01-01

    Motivated by the recent photochlorination experiment [B. Li et al., ACS Nano 5, 5957 (2011)], we study theoretically the interaction of chlorine with graphene. In previous theoretical studies, covalent binding between chlorine and carbon atoms has been elusive upon adsorption to the graphene basal plane. Interestingly, in their recent experiment, Li et al. interpreted their data in terms of chemical bonding of chlorine on top of the graphene plane, associated with a change from sp2 to sp3 in ...

  8. Potassium chloride production by microcline chlorination

    Energy Technology Data Exchange (ETDEWEB)

    Orosco, Pablo, E-mail: porosco@unsl.edu.ar [Instituto de Investigaciones en Tecnología Química (INTEQUI), Chacabuco y Pedernera, San Luis (Argentina); Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, Chacabuco y Pedernera, San Luis (Argentina); Ruiz, María del Carmen [Instituto de Investigaciones en Tecnología Química (INTEQUI), Chacabuco y Pedernera, San Luis (Argentina)

    2015-08-10

    Highlights: • Use of chlorination for the KCl production. • The reagents used were microcline, hydromagnesite and chlorine. • Isothermal and non-isothermal assays were performed in Cl{sub 2}–N{sub 2} mixture. • The chlorination generated KCl at 700 °C. • The chlorination products promote KCl formation. - Abstract: The potassium chloride is one of the most important fertilizers used in agriculture. The current demand of this salt makes interesting the study of potassium chloride production from unconventional potassium resources. In this work the potassium chloride production by chlorination of microcline was investigated. The starting reagents were microcline, hydromagnesite and chlorine. Non-isothermal and isothermal chlorination assays were carried out in a thermogravimetric device adapted to work in corrosive atmospheres. The temperature effect on potassium extraction and the phase transformations produced during chlorination of microcline were studied. The reagents and reaction products were analyzed by X-ray fluorescence (XRF) and X-ray diffraction (XRD). The experimental results indicated that by chlorination of microcline an important extraction of potassium in the temperature range from 800 to 900 °C was produced. Moreover, at 800 °C the forsterite, enstatite and magnesium aluminate spinel phases were generated.

  9. The chlorination of cyclopentanone and cyclohexanone

    NARCIS (Netherlands)

    Maatman, Hendrik

    1980-01-01

    In this thesis the results of an investigation of the chlorination of cyclopentanone and cyclohexanone in the solvent carbontetrachloride and catalyzed by hydrogen chloride are described. ... Zie: Summary

  10. [Neurotoxicology of pesticides].

    Science.gov (United States)

    Ichikawa, Hiroo

    2015-01-01

    Pesticides have been used for many years for preventing, destroying, repelling, or mitigating pests such as insects, rodents, and weeds. However, most pesticides are not completely specific for pests and can also induce damage to the human nervous system. In particular, insecticides often directly targets the nervous system by affecting major targets such as the neuro-transmitter metabolism, neuronal receptors, and ion channels; acetylcholine (ACh) esterase for organo-phosphates and carbamates, nicotinic ACh receptor for neonicotinoids, γ-aminobutyric acid receptors/chloride channels for organochlorides and fipronil, and voltage-gated sodium channel for pyrethroids. Additional targets include sites in the sodium channels, glutamate-gated chloride channels, and octopamine and ryanodine receptors. Several pesticides also produce adverse neurological effects indirectly by disrupting the general cellular mechanisms that support the high metabolic activity of the nervous system. Nowadays, more potent pesticides are being developed as replacements for the older, harmful ones. Pesticide neurotoxicity in humans may involve the central or peripheral nervous system or both and may induce typical neuronal damage in case of acute poisoning even by new agents. However, whether effect of exposure to pesticides at below acute-poisoning threshold level remains unclear. Moreover, neurotoxicology for behavioral and higher-brain function remains an unresolved and a challenging problem.

  11. High resolution spectrophotometry for identification of chlorine dioxide in concentrated chlorine solutions.

    Science.gov (United States)

    Gauw, R D; Emmert, G L; Bubnis, B; Gordon, G

    1999-12-01

    Electrolyzed salt brine generators hold great promise for water disinfection in small communities and remote locations. Electrolysis cell liquors have been reported to contain chlorine, chlorine dioxide and ozone. High resolution spectrophotometry was used to observe the presence (or absence) of a unique spectral absorbance pattern present in solutions containing 1-2 mg/l chlorine dioxide. PMID:18967802

  12. [Chlorination byproducts formation potentials of typical nitrogenous organic compounds in water].

    Science.gov (United States)

    Xu, Qian; Xu, Bin; Qin, Cao; Xia, Sheng-Ji; Gao, Nai-Yun; Tian, Fu-Xiang; Li, Da-Peng

    2011-07-01

    Twelve typical nitrogenous organic compounds including herbicides, pesticides, amino acids, industrial products etc in polluted raw water were selected to investigate formation of typical carbonaceous and nitrogenous DBPs during chlorination and chloramination. To indentify the formation mechanism of carbonaceous and nitrogenous disinfection byproducts from nitrogenous chemicals, chlorination and chloroamination of urea herbicides, triazine herbicides, amino acid, and other compounds were investigated. As a result, the potential precursors for different DBPs were defined as well. It has been identified that widely used urea herbicides could produce as many as 9 specific DBPs. The chlorotoluron shows highest reactivity and yields chloroform (CF), monochloroacetic acid (MCAA), dichloroacetic acid (DCAA), 1,1-dichloro-acetone (1,1-DCP), 1,1,1-trichloro-acetone (1,1,1-TCP), chloropicrin (NTCM), dichloro-acetonitrile (DCAN), dimethylnitrosamine (NDMA). The results indicated that aldicarb and dinoseb are important precursors of CF, DCAA, MCAA, NTCM as well. High concentrations of CF and DCAA were found during L-tryptophan chlorination. Furthermore, DBPs formation pathways and mechanisms were suggested during chlorination and chloramination of chlorotoluron, ametryn, dinoseb L-tryptophan.

  13. Formation of chlorinated lipids post-chlorine gas exposure.

    Science.gov (United States)

    Ford, David A; Honavar, Jaideep; Albert, Carolyn J; Duerr, Mark A; Oh, Joo Yeun; Doran, Stephen; Matalon, Sadis; Patel, Rakesh P

    2016-08-01

    Exposure to chlorine (Cl2) gas can occur during accidents and intentional release scenarios. However, biomarkers that specifically indicate Cl2 exposure and Cl2-derived products that mediate postexposure toxicity remain unclear. We hypothesized that chlorinated lipids (Cl-lipids) formed by direct reactions between Cl2 gas and plasmalogens serve as both biomarkers and mediators of post-Cl2 gas exposure toxicities. The 2-chloropalmitaldehyde (2-Cl-Pald), 2-chlorostearaldehyde (2-Cl-Sald), and their oxidized products, free- and esterified 2-chloropalmitic acid (2-Cl-PA) and 2-chlorostearic acid were detected in the lungs and plasma of mouse and rat models of Cl2 gas exposure. Levels of Cl-lipids were highest immediately post-Cl2 gas exposure, and then declined over 72 h with levels remaining 20- to 30-fold higher at 24 h compared with baseline. Glutathione adducts of 2-Cl-Pald and 2-Cl-Sald also increased with levels peaking at 4 h in plasma. Notably, 3-chlorotyrosine also increased after Cl2 gas exposure, but returned to baseline within 24 h. Intranasal administration of 2-Cl-PA or 2-Cl-Pald at doses similar to those formed in the lung after Cl2 gas exposure led to increased distal lung permeability and inflammation and systemic endothelial dysfunction characterized by loss of eNOS-dependent vasodilation. These data suggest that Cl-lipids could serve as biomarkers and mediators for Cl2 gas exposure and toxicity. PMID:27324796

  14. Behavior of chlorine in lake water

    International Nuclear Information System (INIS)

    Water from monsoon fed Sagre lake is being used as a source of raw water for Tarapur Atomic Power Station (TAPS--1 and 2). The raw water from the lake is initially pumped to Sagre water treatment plant (SWTP) operated by Maharashtra Industrial Development Corporation (MIDC) from where, the processed water is sent to cater the needs of both the units of TAPS-1 and 2, townships of TAPS and MIDC, and the nearby villages. At the SWTP the raw water is treated with alum to remove the turbidity, filtered and chlorinated using bleaching powder. All these years the raw water is chlorinated in such a way whereby a residual chlorine level of 0.5-1.0 mg/l, is maintained at the outlet of water treatment plant. The adequacy of the current chlorination practice was investigated, at the request of the NPC-500 MWe group during 1990, so that the future requirements of raw water for TAPP-3 and 4, can be met from the expanded SWTP. In this connection experiments on chlorine dose -- residual chlorine relationship and the decay pattern of chlorine with time was carried out in the lake water (with low value of total dissolved solids and total hardness 3 sample at the site. The total bacterial count in the raw water observed to be 107 counts/ml originally came down to 103 counts/ml at the end of one-hour exposure time to chlorine. It was found that the chlorine demand of the water was around 6 mg/l. In addition Jar test to evaluate the aluminum dose was also carried out. Based on these experiments a chlorine dose of 6 mg/l for one hour contact time was arrived at. The experimental findings were in agreement with the current chlorination practices. (author)

  15. Process for producing hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Doi, K.; Komatsu, A.; Moroe, M.; Moroe, T.

    1980-07-22

    A process is described for producing a hydrocarbon product consisting essentially of hydrocarbons having about 10 to 50 carbon atoms with 60% or more of said product consisting of hydrocarbons containing 25 to 32 carbon atoms which comprises subjecting a synthetic polyisoprene rubber having 92 to 97% cis-type double bods to a thermally destructive distillation at about 300 to 400/sup 0/ C for about 30 minutes under a reduced pressure of about 0.1 to 5 mm. Hg to obtain said hydrocarbon product consisting essentially of hydrocarbons having about 10 to 50 carbon atoms with 60% or more of said product consisting of hydrocarbons containing 25 to 35 carbon atoms, said hydrocarbon product not having a bad odor and containing scarcely any resinous material.

  16. Chlorine dioxide and by-products in water distribution systems

    OpenAIRE

    Ferreira, Francisco Cardoso

    1991-01-01

    Chlorine dioxide is used as both a pre-oxidant and/or a post-disinfectant in several water treatment plants in the United States. Chlorine dioxide is associated with its byproducts chlorite and chlorate. Chlorine dioxide, chlorine, chlori te and chlorate were sampled in four distribution systems where chlorine dioxide is used for disinfection purposes: Charleston, WV, Columbus, GA, New Castle, PA, and Skagit, WA. The fate of chlorine dioxide and its by-products in dist...

  17. Inactivation of simian rotavirus SA11 by chlorine, chlorine dioxide, and monochloramine.

    OpenAIRE

    Berman, D.; Hoff, J C

    1984-01-01

    The kinetics of inactivation of simian rotavirus SA11 by chlorine, chlorine dioxide, and monochloramine were studied at 5 degrees C with a purified preparation of single virions and a preparation of cell-associated virions. Inactivation of the virus preparations with chlorine and chlorine dioxide was studied at pH 6 and 10. The monochloramine studies were done at pH 8. With 0.5 mg of chlorine per liter at pH 6, more than 4 logs (99.99%) of the single virions were inactivated in less than 15 s...

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

    OpenAIRE

    Emans HJB; Beek MA; Linders JBHJ

    1992-01-01

    In this report a risk assessment or evaluation system for agricultural pesticides is presented, which estimates the hazards for man and environment resulting from the use of these pesticides. The evaluation system has also been placed within the context of the Uniform System for the Evaluation of Substances (USES). 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 c...

  19. Spatial and temporal distribution of pesticide air concentrations in Canadian agricultural regions

    Science.gov (United States)

    Yao, Yuan; Tuduri, Ludovic; Harner, Tom; Blanchard, Pierrette; Waite, Don; Poissant, Laurier; Murphy, Clair; Belzer, Wayne; Aulagnier, Fabien; Li, Yi-Fan; Sverko, Ed

    The Canadian Pesticide Air Sampling Campaign was initiated in 2003 to assess atmospheric levels of pesticides, especially currently used pesticides (CUPs) in agricultural regions across Canada. In the first campaign during the spring to summer of 2003, over 40 pesticides were detected. The spatial and temporal distribution of pesticides in the Canadian atmosphere was shown to reflect the pesticide usage in each region. Several herbicides including triallate, bromoxynil, MCPA, 2,4-D, dicamba, trifluralin and ethalfluralin were detected at highest levels at Bratt's Lake, SK in the prairie region. Strong relationships between air concentrations and dry depositions were observed at this site. Although no application occurred in the Canadian Prairies in 2003, high air concentrations of lindane ( γ-hexachlorocyclohexane) were still observed at Bratt's Lake and Hafford, SK. Two fungicides (chlorothalonil and metalaxyl) and two insecticides (endosulfan and carbofuran) were measured at highest levels at Kensington, PEI. Maximum concentrations of chlorpyrifos and metolachlor were found at St. Anicet, QC. The southern Ontario site, Egbert showed highest concentration of alachlor. Malathion was detected at the highest level at the west coast site, Abbotsford, BC. In case of legacy chlorinated insecticides, high concentrations of DDT, DDE and dieldrin were detected in British Columbia while α-HCH and HCB were found to be fairly uniform across the country. Chlordane was detected in Ontario, Québec and Prince Edward Island. This study demonstrates that the sources for the observed atmospheric occurrence of pesticides include local current pesticide application, volatilization of pesticide residues from soil and atmospheric transport. In many instances, these data represent the first measurements for certain pesticides in a given part of Canada.

  20. GC/MIP/AED method for pesticide residue determination in fruits and vegetables.

    Science.gov (United States)

    Ting, K C; Kho, P

    1991-01-01

    This research describes the results of a gas chromatography/microwave induced plasma/atomic emission detection (GC/MIP/AED) method performed on a Hewlett-Packard 5921A system for pesticide residue analysis in fruits and vegetables. A total of 6 experiments were conducted: (1) sensitivity and linearity studies for elements S, P, Cl, and N by analyzing dursban; (2) a study of instrument response to Cl concentration in pesticide molecules; (3) organochlorinated pesticide recoveries; (4) organophosphate pesticide recoveries; (5) carbamate pesticide recoveries; and (6) investigation of metallic pesticides with plictran and vendex as standards. The rank according to sensitivity and linearity was found to be as follows: S-181 greater than P-178 greater than Cl-479 greater than N-174. Instrument response to the concentration of chlorine atoms in the pesticide molecule was linear, with a correlation coefficient of 0.89. Recoveries of organochlorinated pesticides were 91.7-109.3%, with the exception of citrus, whose recovery was affected by coeluting interferences. Organophosphate recoveries were 73.2% or higher, except for the cygon oxygen analog, which degraded in the GC system under all circumstances. Carbamate recoveries were inconsistent quantitatively; however, the information generated from elements N and S were useful for qualitative confirmation of other methods, such as LC postcolumn derivatization analysis. Overall, the GC/MIP/AED method is powerful for qualitative confirmation in pesticide residue analysis. The instrument's capability of acquiring multi-elements (Cl and P) selectively and accurately is an alternative method for organochlorinated and organophosphate pesticide residue analyses. In addition, the GC/MIP/AED system is easy to use, simple to maintain, and its chromatograms can be interpreted by any chromatography analyst without much prior training. PMID:1757425

  1. 21 CFR 173.300 - Chlorine dioxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Chlorine dioxide. 173.300 Section 173.300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SECONDARY DIRECT FOOD ADDITIVES PERMITTED IN FOOD FOR HUMAN CONSUMPTION Specific Usage Additives § 173.300 Chlorine...

  2. Elements from chlorine to calcium nuclear reactions

    CERN Document Server

    Kunz, Wunibald

    1968-01-01

    Nuclear Tables: Part II Nuclear Reactions, Volume 3: The Elements from Chlorine to Calcium contains tabulations of the nuclear reaction values of elements chlorine, argon, potassium, and calcium. These tabulations provide the calculated Q-values of the elements and their isotopes. This book will be of value to general chemistry researchers.

  3. Chlorine

    Science.gov (United States)

    ... Del.icio.us Digg Facebook Google Bookmarks Technorati Yahoo MyWeb Updates Subscribe Listen Page last reviewed April ... Del.icio.us Digg Facebook Google Bookmarks Technorati Yahoo MyWeb Download page Subscribe to RSS Get email ...

  4. Pesticide Movement in Response to Furrow Irrigation and Pesticide Parameters

    OpenAIRE

    Peralta, Richard C.; Hill, Robert W.; Deer, Howard

    1991-01-01

    Production of adequate supplies of food and fiber currently requires that pesticides be used to limit crop losses from insects, pathogens, weeds and other pests. The term pesticide refers to a large number ofchemical compounds. Pesticides include acaricides, fungicides, herbicides, insecticides, nematicides, algicides, arboricides, zoocides, and many more.

  5. Decontaminating pesticide protective clothing.

    Science.gov (United States)

    Laughlin, J

    1993-01-01

    The review of recent work on the mechanisms of soil removal from textiles assists in understanding decontamination of pesticide protective clothing. The current work provides explanatory conclusions about residue retention as a basis of making recommendations for the most effective decontamination procedures. A caution about generalizations: Some pesticides produce very idiosyncratic responses to decontamination. An example is the paraquat/salt response. Other pesticides exhibit noticeable and unique responses to a highly alkaline medium (carbaryl), or to bleach (chlorpyrifos), or are quickly volatilized (methyl parathion). Responses such as these do not apply to other pesticides undergoing decontamination. Given this caution, there are soil, substrate, and solvent responses that do maximize residue removal. Residue removal is less complete as the concentration of pesticide increases. The concentration of pesticide in fabric builds with successive exposures, and the more concentrated the pesticide, the more difficult the removal. Use a prewash product and/or presoak. The surfactant and/or solvent in a prewash product is a booster in residue removal. Residues transfer from contaminated clothing to other clothing during the washing cycle. Use a full washer of water for a limited number of garments to increase residue removal. The hotter the washing temperature, the better. Generally, this means a water temperature of at least 49 degrees C, and preferably 60 degrees C. Select the detergent shown to be more effective for the formulation: heavy-duty liquid detergents for emulsifiable concentrate formulations and powdered phosphate detergents for wettable powder formulations. If the fabric has a soil-repellent finish, use 1.25 times the amount recommended on the detergent label. For water hardness above 300 ppm, an additional amount of powdered phosphate detergent is needed to obtain the same level of residue removal as obtained with the heavy-duty liquid detergent when

  6. Human Health Benchmarks for Pesticides

    Data.gov (United States)

    U.S. Environmental Protection Agency — Advanced testing methods now allow pesticides to be detected in water at very low levels. These small amounts of pesticides detected in drinking water or source...

  7. Internal chlorination of Ni-Cr alloys

    Energy Technology Data Exchange (ETDEWEB)

    Berztiss, D.; Hennesen, K.; Grabke, H.J. [Max-Planck-Institut fuer Eisenforschung GmbH, Duesseldorf (Germany)

    1998-12-31

    In contrast to internal oxidation, sulfidation and carburization, very little information is available regarding internal chlorination, especially diffusion of chlorine in metallic alloys. This paper describes results of experiments on Ni-Cr alloys (<10 wt% Cr) exposed in an atmosphere containing radioactive HCl. The diffusion of chlorine in the alloy can be determined by measurement of residual {beta}-activity from the sample surface. Successively thin layers (0.5-10 {mu}m) of the alloy were removed by lapping and the surface activity was measured to obtain a depth profile. Both single and polycrystalline materials were tested. Through this work it should be determined if there is in fact solubility and diffusion of chlorine in Ni-based alloys as some authors have proposed or if the ingress of chlorine is mainly a grain boundary phenomenon. (orig.)

  8. Contamination of organochlorine pesticides in sediments from the Arabian Sea along the west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Sarkar, A.; Nagarajan, R.; Chaphadkar, S.; Pal, S.; Singbal, S.Y.S.

    control programme. On with larger surface area and those with organic average the annual consumption of various pesti- content show the highest adsorption capacity (Elder cides in India is about 75,000 metric tons of which and Weber, 1980). 48... influence the variation in concentration of various PCB components. Neth. J. Sea Res. 17, 19-38. organochlorine pesticides in sediment of different Elder G. and Weber K. (1980) Chlorinated phenols in characteristics (Sarkar, 1994; Fisher et al., 1983...

  9. Pesticides and earthworms. A review

    OpenAIRE

    Pelosi, Céline; Barot, Sebastien; Capowiez, Yvan; Hedde, Mickaël; Vandenbulcke, Franck

    2014-01-01

    International audience Earthworms provide key soil functions that favour many positive ecosystem services. These services are important for agroecosystem sustainability but can be degraded by intensive cultural practices such as use of pesticides. Many literature reports have investigated the effect of pesticides on earthworms. Here, we review those reports to assess the relevance of the indicators of earthworm response to pesticides, to assess their sensitivity to pesticides, and to highl...

  10. Shanghai Pesticide Research Institute (SPRI)

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Shanghai Pesticide Research Institute (SPRI), established in 1963, is the first professional pesticide institute in China. After being approved by the Science & Technology Committee of PRC, it became the base for Shanghai Branch of National Pesticide R&D South center.

  11. Control of Pesticides 2004

    DEFF Research Database (Denmark)

    Krongaard, T.; Petersen, K. K.; Christoffersen, C.

    Four different groups of products covered by the pesticide regulation were included in the 2004 analytical chemical authority control: 1) Herbicides containing bentazone, dicamba, dichlorprop-P, mecoprop-P, MCPA, foramsulfuron, iodosulfuron-methylsodium, rimsulfuron and triasulfuron. 2) Fungicides...... coumatetralyl and one out of four contained dicamba complied with the accepted tolerance limits with respect to the content of the active ingredient as specified in Danish Statutory Order on pesticides. None of the examined samples contained OPEO, but one of the samples contained NPEO. On three products...

  12. On the paradox of pesticides

    OpenAIRE

    Li, Y. Charles; Yang, Yipeng

    2013-01-01

    The paradox of pesticides was observed experimentally, which says that pesticides may dramatically increase the population of a pest when the pest has a natural predator. Here we use a mathematical model to study the paradox. We find that the timing for the application of pesticides is crucial for the resurgence or non-resurgence of the pests. In particular, regularly applying pesticides is not a good idea as also observed in experiments. In fact, the best time to apply pesticides is when the...

  13. Development and in situ implementation of a chemical process for reductive dechlorination of chlorinated solvents in polluted aquifers

    OpenAIRE

    Betelu, Stéphanie; Rodrigues, Romain; Noel, Cécile; Colombano, Stéfan; Simon, Apolline; Epardeau, Patrick; Marion, Roland; Ignatiadis, Ioannis

    2015-01-01

    International audience Reductive dechlorination (RDC), using strong reducers, is one of the most important emerging remediation techniques for chlorinated hydrocarbons (CHC). RDC by Nanosized Zero Valent Iron (NZVI) is a powerful electrochemical redox system that has shown promising experimental results for the development of remediation technologies to treat contaminated sites [1, 2]. Although NZVI has excellent characteristics as environmental reactant, its application to the contaminate...

  14. Distribution CharaCteristiCs of 22 OrganoChlorine PestiCides in Soils from Some Areas of the Yangtze River Delta%长三角部分地区土壤中22种有机氯农药的分布特征

    Institute of Scientific and Technical Information of China (English)

    时磊; 孙艳艳; 吕爱娟; 蔡小虎; 沈小明; 沈加林

    2016-01-01

    In order to evaluate the agricultural ecological environment risk caused by industrialization over a long period of time,the distribution characteristics of 22 organochlorine pesticide residues in the soils under different land use forms from four perpendicular profiles were analyzed using Gas Chromatography. Research results indicate that the mean concentrations of OCPs were in the order:vegetable land in industrial park(139. 87 ng / g)> waste land in industrial park(103. 1 ng / g)> vegetable land in agricultural areas(26. 27 ng / g)> paddy field in agricultural areas(2. 50 ng / g). DDTs and HCHs were still the primary pollutants of OCPs in the topsoils with DDTs concentrations of 0. 14 - 485. 73 ng / g(mean 44. 43 ng / g)and HCHs concentrations of 0. 69 - 66. 69 ng / g(mean 7. 73 ng / g). The ratio of(DDD + DDE)/ DDTs indicated that there was almost no new input of pollution in this area. The concentrations of DDTs and HCHs tend to decrease gradually with the increase in the depth of soil profile. This trend is related to the fact that the rock types of zone of aeration in profile soil are mainly clays and sub-clays,which reduce the vertical transfer dynamics of organochlorine pesticides induced by the overland runoff. This study provides some references to the control and improvement of pollution conditions in the region.%针对长三角地区长期工业化对农业生态环境构成较大风险,本文利用气相色谱法对该地区不同利用类型土壤中 22 种有机氯农药进行测定,研究了有机氯农药的残留状况及其在 4 条土壤垂向剖面中的分布特征.结果表明,不同利用类型表层土壤中有机氯农药残留平均值为工业园区菜地(139. 87 ng / g)> 工业园区荒地(103. 1 ng / g)> 农业区传统菜地(26. 27 ng / g)> 农业区水稻田(2. 50 ng / g).表层土壤中 DDTs 和HCHs 是主要污染物,DDTs 含量为 0. 14 ~ 485. 73 ng / g(均值 44. 43 ng / g),HCHs 含量为 0. 69 ~ 66. 69 ng / g (均值 7. 73 ng

  15. Kombinationseffekter af pesticider

    DEFF Research Database (Denmark)

    Kudsk, Per; Andersen, Helle Raun; Cedergreen, Nina;

    Resumé: Effekten af 101 tokomponentblandinger og 20 trekomponentblandinger bestående af 22 forskellige pesticider blev undersøgt i 7 forskellige testsystemer. Effekterne af blandingerne blev sammenholdt med pesticidernes virkningsmekanismer/virkemåder med henblik på at undersøge, om det med...

  16. Photocatalytic Degradation of Pesticides in Natural Water: Effect of Hydrogen Peroxide

    Directory of Open Access Journals (Sweden)

    Natividad Miguel

    2012-01-01

    Full Text Available The aim of this paper is to evaluate the effectiveness of photocatalytic treatment with titanium dioxide in the degradation of 44 organic pesticides analyzed systematically in the Ebro river basin (Spain. The effect of the addition of hydrogen peroxide in this treatment is studied, and a monitoring of effectiveness of photocatalytic processes is carried out by measurements of physical-chemical parameters of water. The application of photocatalytic treatment with 1 g L−1 of TiO2 during 30 minutes achieves an average degradation of the studied pesticides of 48%. Chlorine demand, toxicity, and dissolved organic carbon (DOC concentration of water are reduced. If hydrogen peroxide is added with a concentration of 10 mM, the average degradation of pesticides increases up to 57%, although chlorine demand and toxicity of water increase while DOC concentration remains unchanged with this treatment. The application of either photocatalytic treatments does not produce variations in the physical-chemical parameters of water, such as pH, conductivity, colour, dissolved oxygen, and hardness. The pesticides which are best degraded by photocatalytic treatments are parathion methyl, chlorpyrifos, α-endosulphan, 3,4-dichloroaniline, 4-isopropylaniline, and dicofol while the worst degraded are HCHs, endosulphan-sulphate, heptachlors epoxide, and 4,4′-dichlorobenzophenone.

  17. A comparison of the virucidal properties of chlorine, chlorine dioxide, bromine chloride and iodine.

    OpenAIRE

    Taylor, G R; Butler, M

    1982-01-01

    Chlorine dioxide, bromine chloride and iodine were compared with chlorine as virucidal agents. Under optimal conditions all disinfectants were effective at low concentrations, but each disinfectant responded differently to acidity and alkalinity. Disinfection by chlorine was impaired by the presence of ammonia, but the other disinfectants retained much of their potency. Disinfection of poliovirus by iodine resulted in structural changes in the virions as seen by electron micrroscopy, but the ...

  18. Evaluation of Four Bio fertilizers for Bioremediation of Pesticide contaminated Soil

    International Nuclear Information System (INIS)

    Experiments were conducted to asses the ability of mixed populations of microorganisms which produced as a bio fertilizers by the General Organization of Agriculture Fund, Ministry of Agriculture, Egypt (phosphoren, microbien, cerealin and azospirillum) to degrade five selected pesticides representing different classes including organophosphate, carbamate and chlorinated organic compounds. There were differences in rates of biotransformation, suggesting the selective induction of certain metabolic enzymes. Inoculation of soil incorporated with malathion, fenamiphos, carbaryl, aldicarb and dieldrin, resulted in ca. 80-90% removal of malathion and fenamiphos within 8 days, carbaryl and aldicarb within 11-15 days respectively. Dieldrin removal occurred slowly within 2 months. These data suggest that bioremediate may act as potential candidates for soil inoculation to bioremediate pesticide contaminated soil. The production of Co2 (soil respiration ) was stimulated by some pesticides. In samples with microbien, an about 2 times higher Co2 production was measured

  19. Chlorination of organic material in different soil types

    OpenAIRE

    Gustavsson, Malin

    2009-01-01

    Research has shown that formation of chlorinated organic matter occurs naturally and that organic chlorine is as abundant as the chloride ion in organic soils. A large number of organisms are known to convert inorganic chloride (Clin) to organic chlorine (Clorg) (e.g. bacteria, lichen, fungi and algae) and some enzymes associated to these organisms are capable of chlorinating soil organic matter. The aim with the study was to compare organic matter chlorination rates in soils from several dif...

  20. Ozone depletion and chlorine loading potentials

    Science.gov (United States)

    Pyle, John A.; Wuebbles, Donald J.; Solomon, Susan; Zvenigorodsky, Sergei; Connell, Peter; Ko, Malcolm K. W.; Fisher, Donald A.; Stordal, Frode; Weisenstein, Debra

    1991-01-01

    The recognition of the roles of chlorine and bromine compounds in ozone depletion has led to the regulation or their source gases. Some source gases are expected to be more damaging to the ozone layer than others, so that scientific guidance regarding their relative impacts is needed for regulatory purposes. Parameters used for this purpose include the steady-state and time-dependent chlorine loading potential (CLP) and the ozone depletion potential (ODP). Chlorine loading potentials depend upon the estimated value and accuracy of atmospheric lifetimes and are subject to significant (approximately 20-50 percent) uncertainties for many gases. Ozone depletion potentials depend on the same factors, as well as the evaluation of the release of reactive chlorine and bromine from each source gas and corresponding ozone destruction within the stratosphere.

  1. Photostability of different chlorine photosensitizers

    International Nuclear Information System (INIS)

    In this paper, we report the photodegradation of three different chlorine photosensitizers (Photoditazine®, Radachlorin®, and Foscan®). The photosensitizer degradation was analyzed by changes in the fluorescence spectrum during illumination. The rate of fluorescence variation was normalized to the solution absorption and the photon energy resulting in the determination of the necessary number of photons to be absorbed to induce photosensitizer photodegradation. The parameter for rate of the molecules decay, the photon fluence rate and optical properties of the solution allow us to determine the photosensitizer stability in solution during illumination. The results show that the order of susceptibility for photodegradation rate is: Radachlorin® < Photoditazine® < Foscan®. This difference in the photodegradation rate for Foscan can be explained by the high proportion of aggregates in solution that inhibit the photo-oxidative process that impede the singlet oxygen formation. We hypothesize that there is a correlation between photodegradation rate and photodynamic efficacy witch is governed by the singlet oxygen formation responsible for the most relevant reaction of the cell death photodynamic induction. Then its is important to know the photostability of different types of drugs since the photodegradation rate, the photodegradation as well as the photodynamic efficacy are strong correlated to the oxygen concentration in the tissue

  2. Chlorine Abundances in Cool Stars

    CERN Document Server

    Maas, Z G; Hinkle, K

    2016-01-01

    Chlorine abundances are reported in 15 evolved giants and one M dwarf in the solar neighborhood. The Cl abundance was measured using the vibration-rotation 1-0 P8 line of H$^{35}$Cl at 3.69851 $\\mu$m. The high resolution L-band spectra were observed using the Phoenix infrared spectrometer on the Kitt Peak Mayall 4m telescope. The average [$^{35}$Cl/Fe] abundance in stars with --0.72$<$[Fe/H]$<$0.20 is [$^{35}$Cl/Fe]=(--0.10$\\pm$0.15) dex. The mean difference between the [$^{35}$Cl/Fe] ratios measured in our stars and chemical evolution model values is (0.16$\\pm$0.15) dex. The [$^{35}$Cl/Ca] ratio has an offset of $\\sim$0.35 dex above model predictions suggesting chemical evolution models are under producing Cl at the high metallicity range. Abundances of C, N, O, Si, and Ca were also measured in our spectral region and are consistent with F and G dwarfs. The Cl versus O abundances from our sample match Cl abundances measured in planetary nebula and \\ion{H}{2} regions. In one star where both H$^{35}$Cl a...

  3. Formation of chlorinated organic compounds in fluidized bed combustion of recycled fuels

    International Nuclear Information System (INIS)

    Four tests of co-combustion of recycled fuels (REP) with peat and coal in the 15 kW fluidized bed reactor were performed. The recycled fuel was so-called dry fraction in four vessels sampling at Keltinmaeki. In three tests a part of peat energy was replaced with coal. The mixtures were prepared so that in all mixtures 25 % of energy was recycled fuel and 75 % was either peat or the mixture of peat and coal. The concentrations of polyaromatic hydrocarbons (PAH), polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) and chlorophenols decreased with increasing part of coal due to the increasing sulphur/chlorine ratio. Principal Component Analysis (PCA) and Partial Least Square regression analysis (PLS) showed that the chlorine, copper and sulphur contents of the fuel effected most on the concentrations of chlorophenols, chlorobenzenes, PCBs and PCDDs/PCDFs. Other variables influencing on a model were the lead concentration and the sulphur/chlorine ratio in fuel and the hydrogen chloride concentration of the flue gas. The concentrations of chlorophenols and chlorobenzenes were also significant for PCDD/PCDF concentrations in flue gas. The sulphur, chlorine, copper and chromium contents in fly ash and the temperature of the reactor influenced on the chlorophenol, chlorobenzene, PCB and PCDD/PCDF concentrations in fly ash. The chlorophenol and chlorobenzene contents in fly ash, the sulphur/chlorine ratio and the lead content in fuel, the sulphur dioxide, hydrogen chloride and carbon monoxide concentrations in flue gas had also influence on PCDD/PCDF concentrations in fly ash

  4. Derivation of validated methods of sampling and analysis for intermediate and final products of the anaerobic material utilization of volatile chlorinated hydrocarbons (LCFC) in groundwater in the context of analyses of contaminated soils; Ableitung validierter Probenahme- und Analysenmethoden fuer Zwischen- und Endprodukte der anaeroben Stoffverwertungsprozesse von Leichtfluechtigen Chlorierten Kohlenwasserstoffen (LCKW) im Grundwasser im Rahmen von Altlastenuntersuchungen

    Energy Technology Data Exchange (ETDEWEB)

    Dorgerloh, Ute; Becker, Roland; Win, Tin [Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin (Germany); Theissen, Hubert [IMAGO GbR (Germany)

    2010-06-17

    The results of the project ''Methods of sampling and analysis of intermediate and final products of the anaerobic degradation of volatile halogenated hydrocarbons in groundwater in frame of analysis of contaminated sites'' of the German Federal States Program ''Water, Soil, Waste'' (Laenderfinanzierungsprogramm ''Wasser, Boden, Luft'') LFP B2.08 are presented in these report. Different methods of sampling and analysis for the determination of hydrogen, methane, ethene and vinyl chloride in groundwater are developed and validated: For the sampling are described and discussed: i. active sampling: purge and sample of water samples and purging of solvated gases in groundwater in gas sampling tubes ii. passive sampling: diffusion sampling in polyethylene diffusion bags (PDB) and plastic syringes as diffusion sampler for solvated gases The use of active (purge and sample, downhole sampler) and passive (diffusion sampling) sampling techniques for the quantification of VOC, ethene, and methane are evaluated from the viewpoint of public authorities and regarding the reproducibility of measurement results. Based on a groundwater contaminated with trichloroethene, 1,2-dichloroethene, and vinyl chloride it is shown that passive sampling is restricted by low groundwater flow and biological activity inside the well casing. Therefore, active sampling is to be preferred in case of unknown or insufficient flow conditions in the aquifer. The methods of chromatography for the determination of the compounds are validated and compared with other appropriate analytical methods: I. Headspace-GC-FID for the determination of methane, ethene and vinyl chloride in water of the purged sample (i) and the water of the PDB (ii) II. Direct injection - GC-PDD for the determination of hydrogen from the collected gas samples of the gas sampling tube (i) and the plastic syringes (ii) The gas chromatographic procedure for vinyl chloride using

  5. Radiation induced microbial pesticide

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Yup; Lee, Young Keun; Kim, Jae Sung; Kim, Jin Kyu; Lee, Sang Jae

    2000-01-01

    To control plant pathogenic fungi, 4 strains of bacteria (K1, K3, K4, YS1) were isolated from mushroom compost and hot spring. K4, K1, K3, YS1 strain showed wide antifungal spectrum and high antifungal activities against 13 kinds of fungi. Mutants of K1 and YS1 strains were induced by gamma-ray radiation and showed promising antifungal activities. These wild type and mutants showed resistant against more than 27 kinds of commercial pesticides among 30 kinds of commercial pesticides test particularly, YS1-1006 mutant strain showed resistant against hydrogen oxide. And mutants had increased antifungal activity against Botryoshaeria dothidea. These results suggested that radiation could be an useful method for the induction of functional mutants. (author)

  6. Radiation induced microbial pesticide

    International Nuclear Information System (INIS)

    To control plant pathogenic fungi, 4 strains of bacteria (K1, K3, K4, YS1) were isolated from mushroom compost and hot spring. K4, K1, K3, YS1 strain showed wide antifungal spectrum and high antifungal activities against 13 kinds of fungi. Mutants of K1 and YS1 strains were induced by gamma-ray radiation and showed promising antifungal activities. These wild type and mutants showed resistant against more than 27 kinds of commercial pesticides among 30 kinds of commercial pesticides test particularly, YS1-1006 mutant strain showed resistant against hydrogen oxide. And mutants had increased antifungal activity against Botryoshaeria dothidea. These results suggested that radiation could be an useful method for the induction of functional mutants. (author)

  7. Ecogenomics of microbial communities in bioremediation of chlorinated contaminated sites

    Directory of Open Access Journals (Sweden)

    Farai Maphosa

    2012-10-01

    Full Text Available Organohalide compounds such as chloroethenes, chloroethanes and polychlorinated benzenes are among the most significant pollutants in the world. These compounds are often found in contamination plumes with other pollutants such as solvents, pesticides and petroleum derivatives. Microbial bioremediation of contaminated sites, has become commonplace whereby key processes involved in bioremediation include anaerobic degradation and transformation of these organohalides by organohalide respiring bacteria and also via hydrolytic, oxygenic and reductive mechanisms by aerobic bacteria. Microbial ecogenomics has enabled us to not only study the microbiology involved in these complex processes but also develop tools to better monitor and assess these sites during bioremediation. Microbial ecogenomics have capitalized on recent advances in high-throughput and -output genomics technologies in combination with microbial physiology studies to address these complex bioremediation problems at a system level. Advances in environmental metagenomics, transcriptomics and proteomics have provided insights into key genes and their regulation in the environment. They have also given us clues into microbial community structures, dynamics and functions at contaminated sites. These techniques have not only aided us in understanding the lifestyles of common organohalide respirers, for example Dehalococcoides, Dehalobacter and Desulfitobacterium, but also provided insights into novel and yet uncultured microorganisms found in organohalide respiring consortia. In this paper we look at how ecogenomic studies have aided us to understand the microbial structures and functions in response to environmental stimuli such as the presence of chlorinated pollutants.

  8. Pesticides in Uruguay.

    Science.gov (United States)

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

    2004-01-01

    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

  9. Bromate ion formation in dark chlorination and ultraviolet/chlorination processes for bromide-containing water

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Bormate (BrO3-) is a carcinogenic chemical produced in ozonation or chlorination of bromide-containing water. Although its formation in seawater with or without sunlight has been previously investigated, the formation of bromate in dilute solutions,particularly raw water for water treatment plant, is unknown. In this article, the results of bench scale tests to measure the formation rates of bromate formation in dilute solutions, including de-ionized water and raw water from Yangtze River, were presented in dark chlorination and ultraviolet (UV)/chlorination processes. And the effects of initial pH, initial concentration of NaOCl, and UV light intensity on bromate formation in UV/chlorination of the diluted solutions were investigated. Detectable bromate was formed in dark chlorination of the two water samples with a relatively slow production rate. Under routine disinfecting conditions, the amount of formed bromate is not likely to exceed the national standards (10 μg/L). UV irradiation enhanced the decay of free chlorine, and,simultaneously, 6.6%-32% of Br- was oxidized to BrO3-. And the formation of bromate exhibited three stages: rapid stage, slow stage and plateau. Under the experimental conditions (pH = 4.41-11.07, CCl2= 1.23-4.50 mg/L), low pH and high chlorine concentration favored the generation of bromate. High light intensity promoted the production rate of bromate, but decreased its total generation amount due to acceleration of chlorine decomposition.

  10. 2011 EPA Pesticide General Permit (PGP)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The 2011 EPA Pesticide General Permit (PGP) covers discharges of biological pesticides, and chemical pesticides that leave a residue, in areas where EPA is the...

  11. 76 FR 38160 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2011-06-29

    ... AGENCY Pesticide Products; Registration Applications AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: EPA has received applications to register pesticide products containing an active ingredient not included in any previously registered pesticide products. Pursuant to...

  12. 75 FR 71695 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2010-11-24

    ... AGENCY Pesticide Products; Registration Applications AGENCY: Environmental Protection Agency ACTION: Notice. SUMMARY: EPA has received applications to register new uses for pesticide products containing... Pesticide Programs (OPP) Regulatory Public Docket (7502P), Environmental Protection Agency,...

  13. 75 FR 24694 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2010-05-05

    ... AGENCY Pesticide Products; Registration Applications AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: EPA has received applications to register pesticide products containing an active ingredient not included in any previously registered pesticide product. Pursuant to the...

  14. Atmospheric reactivity of alcohols, thiols and fluoroalcohols with chlorine atoms

    Science.gov (United States)

    Garzon Ruiz, Andres

    Alcohols, thiols and fluoroalcohols are volatile organic compounds (VOCs) which are emitted to the atmosphere from both natural (vegetation, oceans, volcanoes, etc.) and anthropogenic sources (fuels, solvents, wastewater, incinerators, refrigerants, etc.). These pollutants can be eliminated from the troposphere by deposition on the terrestrial surface, direct photolysis or reaction with different tropospheric oxidants. Reactions of VOCs with tropospheric oxidants are involved in the well-known atmospheric phenomenon of photochemical smog or the production of tropospheric ozone. The oxidation of these VOCs in the troposphere is mainly initiated by reaction with OH radicals during the daytime and with NO radicals at night. However, in recent years, the oxidation by chlorine atoms (Cl) has gained great importance in the study of atmospheric reactions because they may exert some influence in the boundary layer, particularly in marine and coastal environments. In general, Cl atoms are much more reactive species than OH and NO; radicals and therefore low concentrations of Cl may compete with OH and NO3 in hydrocarbon oxidation processes. The main source of tropospheric Cl atoms is believed to be the photolysis of chlorine-containing molecules generated by heterogeneous reactions of sea salt aerosols. It has also been proposed that Cl atoms, produced in the photolysis of Cl2 emitted from industrial processes, may enhance hydrocarbon oxidation rates and ozone production in urban environments. In this work, a kinetic, theoretical and mechanistic study of the reaction of several alcohols, thiols, and fluoroalcohols with Cl atoms has been carried out. Pulsed laser photolysis-fluorescence resonance (PLP-RF) technique was used for the kinetic study as a function of temperature and pressure. An environmental chamber-Fourier transform infrared (FTIR) system was also employed in the kinetic studies. Tropospheric lifetimes of these pollutants were estimated using obtained kinetic

  15. Influencing factors and degradation products of antipyrine chlorination in water with free chlorine

    Institute of Scientific and Technical Information of China (English)

    Meiquan Cai; Liqiu Zhang; Fei Qi; Li Feng

    2013-01-01

    Owing to its low cost,free chlorine is one of the most common disinfectants for wastewater and drinking water treatment.However,the formation of disinfection byproducts has been found to occur after free chlorine disinfection in recent decades.Antipyrine (ANT),an anti-inflammatory analgesic,has been frequently detected in the aquatic environment.In this work.the removal efficiency of ANT by free chlorine oxidation in ultrapure water was investigated with batch experiments.The influencing factors on the removal of ANT were explored at initial concentrations of ANT from 0.04 to 0.64 mg/L,free chlorine dosage from 0.30 to 1.31 mg/L,and pH from 1.5 to 9.0.The main degradation products were identified by solid phase extraction-gas chromatography-mass spectrometry.The results showed that ANT reacted rapidly with free chlorine in ultrapure water systems and up to 90.6% removal efficiency of ANT was achieved after 25 sec (initial free chlorine 1 mg/L,ANT 0.5 mg/L,pH 7.0).Higher oxidant dosage,lower ANT initial concentration and low pH favor the ANT removal.The main degradation product in ANT chlorination was a monochlorine substitution product (4-chloro-l,2-dihydro1,5-dimethyl-2-phenyl-3H-pyrazol-3-one),which can be further chlorinated by free chlorine.In addition,the total organic carbon result indicated that ANT is difficult to be mineralized using chlorine.

  16. Influencing factors and degradation products of antipyrine chlorination in water with free chlorine.

    Science.gov (United States)

    Cai, Meiquan; Zhang, Liqiu; Qi, Fei; Feng, Li

    2013-01-01

    Owing to its low cost, free chlorine is one of the most common disinfectants for wastewater and drinking water treatment. However, the formation of disinfection byproducts has been found to occur after free chlorine disinfection in recent decades. Antipyrine (ANT), an anti-inflammatory analgesic, has been frequently detected in the aquatic environment. In this work, the removal efficiency of ANT by free chlorine oxidation in ultrapure water was investigated with batch experiments. The influencing factors on the removal of ANT were explored at initial concentrations of ANT from 0.04 to 0.64 mg/L, free chlorine dosage from 0.30 to 1.31 mg/L, and pH from 1.5 to 9.0. The main degradation products were identified by solid phase extraction-gas chromatography-mass spectrometry. The results showed that ANT reacted rapidly with free chlorine in ultrapure water systems and up to 90.6% removal efficiency of ANT was achieved after 25 sec (initial free chlorine 1 mg/L, ANT 0.5 mg/L, pH 7.0). Higher oxidant dosage, lower ANT initial concentration and low pH favor the ANT removal. The main degradation product in ANT chlorination was a monochlorine substitution product (4-chloro-1,2-dihydro-1,5-dimethyl-2-phenyl-3H-pyrazol-3-one), which can be further chlorinated by free chlorine. In addition, the total organic carbon result indicated that ANT is difficult to be mineralized using chlorine.

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

    NARCIS (Netherlands)

    Emans HJB; Beek MA; Linders JBHJ

    1992-01-01

    In this report a risk assessment or evaluation system for agricultural pesticides is presented, which estimates the hazards for man and environment resulting from the use of these pesticides. The evaluation system has also been placed within the context of the Uniform System for the Evaluation of S

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

    NARCIS (Netherlands)

    Emans HJB; Beek MA; Linders JBHJ

    1992-01-01

    In this report a risk assessment or evaluation system for agricultural pesticides is presented, which estimates the hazards for man and environment resulting from the use of these pesticides. The evaluation system has also been placed within the context of the Uniform System for the Evaluation of Su

  19. Determination of chlorinated polycyclic aromatic hydrocarbons in dust by solid-phase extract(SPE) and gas chromatofraphy-mass spectrometry%固相萃取/气相色谱质谱法测定灰尘中的氯代多环芳烃

    Institute of Scientific and Technical Information of China (English)

    郑继三; 马静; Yuichi Horii; Kurunthachalam Kannan; Takeshi Ohura; 徐刚; 吴明红

    2012-01-01

    A method was developed for the detection of 20 chlorinated polycyclic hydrocarbons(ClPAHs) in dust samples by solid-phase extract(SPE) and gas chromatography-mass spectrometry(GC/MS).The samples were Soxhlet extracted with dichloromethane-hexane mixture for more than 16 h.The extracts were purified through activated silica gel glass column,and then the SPE column self-packed with activated carbon-blended silica gel mixture.After cleanup,the extracts were analyzed by GC/MS in SIM mode,using characteristic ions for quantification.The SPE packed with a 0.2 g mixture of activated carbon-blended silica gel(1 ∶ 40,W/W) was found to have a good selectivity in separating ClPAHs from interference.And it reduced the toxic eluate when the SPE column was back-flushed after the sample extracts were loaded.The linear range,recovery and MDLs of 20 ClPAHs were examined.The recoveries of ClPAHs ranged from 60.4% to 120.1%,and the correlation coefficient was more than 0.99.The pretreatment procedure of this method is easy,and the quantification is sensitive and accurate.The method can be used to detect ClPAHs in many ambient media.%建立了固相萃取(SPE)/气相色谱质谱(GC/MS)联用检测灰尘中氯代多环芳烃(ClPAHs)的方法.以正己烷和二氯甲烷混合液为提取溶剂,索氏提取灰尘样品中的20种ClPAHs,活性硅胶层析柱与活性炭混合硅胶SPE柱协同净化.净化后的提取液采用GC/MS测定,SIM模式扫描,并用质谱特征离子定量分析.结果表明,填充量为0.2 g(W(活性炭)∶W(硅胶)=1∶40)的活性炭混合硅胶SPE小柱能有效地将ClPAHs分离出来,载样后采用反向溶剂洗脱,既提高了回收率又减少了洗脱剂甲苯的用量,净化效果好.处理灰尘样品后检测分析,20种ClPAHs的平均回收率稳定在60.4%—120.1%,相关系数〉0.99,检出限为0.04—0.17 ng.g-1,相对标准偏差为1.6%—10.2%.本方法前处理简单,定性、定量准确可靠,

  20. In situ thermally enhanced biodegradation of petroleum fuel hydrocarbons and halogenated organic solvents

    International Nuclear Information System (INIS)

    An in situ thermally enhanced microbial remediation strategy and a method for the biodegradation of toxic petroleum fuel hydrocarbon and halogenated organic solvent contaminants are described. The method utilizes nonpathogenic, thermophilic bacteria for the thermal biodegradation of toxic and carcinogenic contaminants, such as benzene, toluene, ethylbenzene and xylenes, from fuel leaks and the chlorinated ethenes, such as trichloroethylene, chlorinated ethanes, such as 1,1,1-trichloroethane, and chlorinated methanes, such as chloroform, from past solvent cleaning practices. The method relies on and takes advantage of the pre-existing heated conditions and the array of delivery/recovery wells that are created and in place following primary subsurface contaminant volatilization efforts via thermal approaches, such as dynamic underground steam-electrical heating. 21 figs

  1. Choice of pesticide fate models

    International Nuclear Information System (INIS)

    The choice of a pesticide fate model at field scale is linked to the available input data. The article describes the available pesticide fate models at a field scale and the guidelines for the choice of the suitable model as function of the data input requested

  2. Investigation of molybdenum pentachloride interaction with chlorine

    International Nuclear Information System (INIS)

    In Raman spectra of molybdenum pentachloride solutions in liquid chlorine lines were recorded in case of 397, 312, 410, 217 and 180 cm-1 vibrations of ν1(A1'), ν2(A1'), ν5(E'), ν6(E') and ν8(E'') monomer (symmetry D3h) molecules of MoCl5. Interaction of molten molybdenum pentachloride with chlorine at increased (up to 6 MPa) pressures of Cl2 was studied. In Raman spectra of its vapour distillation in liquid chlorine alongside with MoCl5 lines appearance of new lines at 363 and 272 cm-1, similar in their frequency to the ones calculated for the vibrations ν1(A1g) and ν2(Eg) of MoCl6 molecules (symmetry Oh), was observed

  3. Studies concerning thermodynamics and kinetics of the absorption of halogenated hydrocarbons relevant to environment

    International Nuclear Information System (INIS)

    In the context of the research project the scrubbing of air contaminated by peculiar volatile organic compounds was investigated using the absorption technique by means of high boiling organics as washing liquids. Eight chlorinated hydrocarbons well known from technical processes were chosen to be representative for the volatile organic compounds. Eleven absorption media were selected on the basis of their physical properties. For the determination of the solubility data of the absorption media due to chlorinated hydrocarbons, nitrogen as well as a mixture of nitrogen and oxygen were used as carrier gas. The influence of the dipole moment of the absorption media on the amount of solubility - expressed as enrichment factor - was studied, too. Concerning the technical application, the thermostability and the stability against diluted inorganic acids were studied as well. (orig.). 56 figs., 8 tabs., 63 refs

  4. Of cabbages and chlorine: cholera in Peru.

    Science.gov (United States)

    1992-07-01

    The low case fatality rates (1%) from the 1991 cholera epidemic in Peru was more a result of including diarrheas of a less virulent etiology than that of cholera. In fact, a study during the early phases of the cholera epidemic in Trujillo, Peru revealed that only 79% of suspected cholera cases were infected with vibrio cholera 01. Further other people contended that the government of Peru did not chlorinate many water supplies because studies by the US Environmental Protection Agency suggested that chlorine increases the cancer risk. It reacts with organic matter to make trihalomethanes. 1 study noted that this risk may explain as many as 700 cases of cancer/year in the US, yet cholera was responsible for nearly 40009 deaths in Latin America the 1st year. Besides in Trujillo, Peru the reason for not chlorinating the water supply was not due to a conscious decision to not do so on the part of the government, but because no funds had been made available to purchase chlorinators and chlorine. This is typical of many towns in developing countries. Further raw fish also played a role in transmitting cholera in Peru. Moreover the study in Trujillo indicated that water stored in containers in the home, and not the water supply, was the most important vehicle of transmission. Nevertheless chlorination of both the water supply and stored water would have prevented cholera transmission. In addition, cabbage irrigated with raw wastewater contributed to cholera transmission in Trujillo. But a concern arises if developing countries follow the advice of WHO of 1st treating wastewater in stabilization ponds. Aquatic blue green algae, other zooplankton, and phytoplankton from a microhabitat suitable for V. cholera. In fact, a study in Peru identified a seasonal pattern of the cholera epidemic with the seasonality of V. cholera non-01 from sewage lagoons in Lima. PMID:1351603

  5. Quality control of pesticide products

    International Nuclear Information System (INIS)

    In light of an established need for more efficient analytical procedures, this publication, which documents the findings of an IAEA coordinated research project (CRP) on “Quality Control of Pesticide Products”, simplifies the existing protocol for pesticide analysis while simultaneously upholding existing standards of quality. This publication includes both a report on the development work done in the CRP and a training manual for use by pesticide analysis laboratories. Based on peer reviewed and internationally recognized methods published by the Association of Analytical Communities (AOAC) and the Collaborative International Pesticides Analytical Council (CIPAC), this report provides laboratories with versatile tools to enhance the analysis of pesticide chemicals and to extend the scope of available analytical repertoires. Adoption of the proposed analytical methodologies promises to reduce laboratories’ use of solvents and the time spent on reconfiguration and set-up of analytical equipment

  6. Occupational exposure to chlorinated and petroleum solvents and mycosis fungoides

    DEFF Research Database (Denmark)

    Morales-Suárez-Varela, Maria M; Olsen, Jørn; Villeneuve, Sara;

    2013-01-01

    To evaluate the potential association between occupational exposure to chlorinated and petroleum solvents and mycosis fungoides (MF).......To evaluate the potential association between occupational exposure to chlorinated and petroleum solvents and mycosis fungoides (MF)....

  7. The effects of low level chlorination and chlorine dioxide on biofouling control in a once-through service water system

    International Nuclear Information System (INIS)

    Continuous chlorination has been successfully used for the control of Corbicula at a nuclear power plant located on the Chattahoochee River in southeastern Alabama, since 1986. The purpose of this study was to investigate further minimization of chlorine usage and determine if chlorine dioxide is a feasible alternative. Four continuous biocide treatments were evaluated for macro and microfouling control effectiveness, operational feasibility, and environmental acceptability. One semi-continuous chlorination treatment was also evaluated for macrofouling control effectiveness. Higher treatment residuals were possible with chlorine dioxide than with chlorination due to the river discharge limitations. At the levels tested, continuous chlorine dioxide was significantly more effective in providing both macro and microfouling control. Semi-continuous chlorination was just as effective as continuous chlorination for controlling macrofouling. The Corbicula treatment programs that were tested should all provide sufficient control for zebra mussels. Chlorine dioxide was not as cost effective as chlorination for providing macrofouling control. The semi-continuous treatment save 50% on chemical usage and will allow for the simultaneous treatment of two service water systems. Chlorite levels produced during the chlorine dioxide treatments were found to be environmentally acceptable. Levels of trihalomethanes in the chlorinated service water were less than the maximum levels allowed in drinking water

  8. Review of chlorination of zirconium dioxide

    International Nuclear Information System (INIS)

    A review of chlorination zirconium dioxide is presented.used semi batch process with vertical reactor, horizontal reactor and fluidized reactor. The feed were zircon dioxide from Aldrich, direct zircon sand and briquette of zircon sand. From the study it is obtained that the best reactor is vertical reactor.It needs modification of chlorination reactor and sublimator to obtain the larger conversion. It is come to reality that zirconium tetrachloride preparation by process is significant with zirconium tetrachloride from Aldrich. It needs the sequel research to get the best result of process. (author)

  9. Determination of chlorine in silicate rocks

    Science.gov (United States)

    Peck, L.C.

    1959-01-01

    In a rapid accurate method for the determination of chlorine in silicate rocks, the rock powder is sintered with a sodium carbonate flux containing zinc oxide and magnesium carbonate. The sinter cake is leached with water, the resulting solution is filtered, and the filtrate is acidified with nitric acid. Chlorine is determined by titrating this solution with mercuric nitrate solution using sodium nitroprusside as the indicator. The titration is made in the dark with a beam of light shining through the solution. The end point of the titration is found by visually comparing the intensity of this beam of light with that of a similar beam of light in a reference solution.

  10. Chlorinated organic compounds produced by Fusarium graminearum.

    Science.gov (United States)

    Ntushelo, Khayalethu

    2016-06-01

    Fusarium graminearum, a pathogen of wheat and maize, not only reduces grain yield and degrades quality but also produces mycotoxins in the infected grain. Focus has been on mycotoxins because of the human and animal health hazards associated with them. In addition to work done on mycotoxins, chemical profiling of F. graminearum to identify other compounds produced by this fungus remains critical. With chemical profiling of F. graminearum the entire chemistry of this fungus can be understood. The focus of this work was to identify chlorinated compounds produced by F. graminearum. Various chlorinated compounds were detected and their role in F. graminearum is yet to be understood. PMID:27165533

  11. Attacks of Asthma due to Chlorinized Water: Case Report

    OpenAIRE

    Murat Eyup Berdan; Ercan Gocgeldi; Sami Ozturk; Ali Kutlu

    2008-01-01

    The presence of a high prevalence of bronchial hyperresponsiveness and asthma-like symptoms in swimmers has been reported. But, attacks of asthma which is related to chlorinized water is rare. Chlorine, a strong oxidizing agent, is an important toxic gas that the swimmer can breath during swimming and a worker can exposed to chlorine while he or she was using water with chlorine at home. We describe a persistent increase in nonspecific bronchial hyperresponsiveness following chronic exposure ...

  12. Hydrology-linked spatial distribution of pesticides in a fjord system in Greenland.

    Science.gov (United States)

    Carlsson, Pernilla; Cornelissen, Gerard; Bøggild, Carl Egede; Rysgaard, Søren; Mortensen, John; Kallenborn, Roland

    2012-05-01

    A pilot study is presented evaluating selected chlorinated pesticides as chemical tracers for water masses in a sub-Arctic fjord system (Godthåbsfjord, western Greenland). Polyoxymethylene (POM) based passive water samplers were deployed during summer-autumn 2010. The levels of the analysed chlorinated pesticides in the fjord surface waters were found to be low compared to earlier studies. α-Hexachlorocyclohexane (α-HCH) and hexachlorobenzene (HCB) were the predominant contaminants. However, these two compounds have higher levels in oceanic water compared to freshwater influenced fjord waters. These chemicals can thus be considered as indicators for direct atmospheric long-range transport, while the organochlorine pesticides like trans-, cis-chlordane, trans-nonachlor and oxychlordane that are detected in the inner parts of the fjord are indicators for potential freshwater sources such as rivers and glacial meltwater runoff (secondary sources). The average values were 50 pg L(-1) for HCB and 11 pg L(-1) for α-HCH. These concentrations are comparable to levels in fjords in Svalbard (Norwegian Arctic), but lower than in open and/or ice covered oceans in the Canadian Arctic. Two air samplers were deployed for the identification of direct atmospheric contributions. Local contamination sources do not contribute significantly. The study demonstrated the value of passive water sampling devices for comprehensive hydrological characterization of Arctic coastal waters.

  13. Hydrology-linked spatial distribution of pesticides in a fjord system in Greenland.

    Science.gov (United States)

    Carlsson, Pernilla; Cornelissen, Gerard; Bøggild, Carl Egede; Rysgaard, Søren; Mortensen, John; Kallenborn, Roland

    2012-05-01

    A pilot study is presented evaluating selected chlorinated pesticides as chemical tracers for water masses in a sub-Arctic fjord system (Godthåbsfjord, western Greenland). Polyoxymethylene (POM) based passive water samplers were deployed during summer-autumn 2010. The levels of the analysed chlorinated pesticides in the fjord surface waters were found to be low compared to earlier studies. α-Hexachlorocyclohexane (α-HCH) and hexachlorobenzene (HCB) were the predominant contaminants. However, these two compounds have higher levels in oceanic water compared to freshwater influenced fjord waters. These chemicals can thus be considered as indicators for direct atmospheric long-range transport, while the organochlorine pesticides like trans-, cis-chlordane, trans-nonachlor and oxychlordane that are detected in the inner parts of the fjord are indicators for potential freshwater sources such as rivers and glacial meltwater runoff (secondary sources). The average values were 50 pg L(-1) for HCB and 11 pg L(-1) for α-HCH. These concentrations are comparable to levels in fjords in Svalbard (Norwegian Arctic), but lower than in open and/or ice covered oceans in the Canadian Arctic. Two air samplers were deployed for the identification of direct atmospheric contributions. Local contamination sources do not contribute significantly. The study demonstrated the value of passive water sampling devices for comprehensive hydrological characterization of Arctic coastal waters. PMID:22481207

  14. PESTICIDE APPLICATION TECHNICS IMPROVEMENT

    Directory of Open Access Journals (Sweden)

    Đuro Banaj

    2011-06-01

    Full Text Available The academic textbook Pesticide application tehnics improvement is the result of several-year recording theoretical models, numerous practical tests, and data collection relating to technical systems in plant protection and its environment in the narrowest sense. In this first edition, the authors cover the area they have dealt with for many years. The authors aimed to present complete and clear methods how to solve specific problems in the agricultural practice management, plant protection, and direct practice application – ‘‘Know- How'', with as many as possible useful data. References used, along with local ones, are mostly American and from Western Europe. This textbook is intended for those who already use the agricultural technique in plant protection and those who are just acquiring the basics of technical systems proper application in daily practice, regardless the size of the agricultural farm. The authors covered in details and explained some bases of physics logic, analysis, and synthesis of specific laws while using pesticides due to extremely importance in understanding the problem area.

  15. Chlorine-rich plasma polymer coating for the prevention of attachment of pathogenic fungal cells onto materials surfaces

    Science.gov (United States)

    Lamont-Friedrich, Stephanie J.; Michl, Thomas D.; Giles, Carla; Griesser, Hans J.; Coad, Bryan R.

    2016-07-01

    The attachment of pathogenic fungal cells onto materials surfaces, which is often followed by biofilm formation, causes adverse consequences in a wide range of areas. Here we have investigated the ability of thin film coatings from chlorinated molecules to deter fungal colonization of solid materials by contact killing of fungal cells reaching the surface of the coating. Coatings were deposited onto various substrate materials via plasma polymerization, which is a substrate-independent process widely used for industrial coating applications, using 1,1,2-trichloroethane as the process vapour. XPS surface analysis showed that the coatings were characterized by a highly chlorinated hydrocarbon polymer nature, with only a very small amount of oxygen incorporated. The activity of these coatings against human fungal pathogens was quantified using a recently developed, modified yeast assay and excellent antifungal activity was observed against Candida albicans and Candida glabrata. Plasma polymer surface coatings derived from chlorinated hydrocarbon molecules may therefore offer a promising solution to preventing yeast and mould biofilm formation on materials surfaces, for applications such as air conditioners, biomedical devices, food processing equipment, and others.

  16. A hand-portable instrument system for the real-time analysis of chlorinated organic compound contamination

    International Nuclear Information System (INIS)

    Working with the DOE Morgantown Energy Technology Center, Transducer Research, Inc. (TRI) recently developed a new chemical monitor which responds selectively to vapors of chlorinated solvents. No response is observed with common hydrocarbon organic compounds such as BTXs (benzene, toluene, xylene) or POLs (petroleum, oil, lubricants), and in fact, no nonhalogen containing chemical has been identified which induces a measurable response. This instrument, 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 groundwater with a unique closed-loop sampler. When interfaced to the samplers, the RCL MONITOR is capable of measuring chlorinated solvent contamination in the vapor phase up to 5,000 ppm and in water and other condensed media from 10 to over 10,000 ppbwt. The performance of RCL MONITOR was demonstrated at several DOE facilities and applications have been identified in which the selective and sensitive measurement and monitoring of chlorinated hydrocarbons is essential. Case studies are currently underway at DOE Hanford and the Idaho National Engineering Laboratory

  17. Blends of caprolactam/caprolactone copolymers and chlorinated polymers

    NARCIS (Netherlands)

    Alberda van Ekenstein, G.O.R.; Deuring, H.; ten Brinke, G.; Ellis, T.S.

    1997-01-01

    The phase behaviour of blends of chlorinated polyethylene, polyvinyl chloride (PVC) and chlorinated PVC with random copolymers of caprolactone and caprolactam has been investigated and the results correlated with a binary interaction model. The known miscibility of polycaprolactone in the chlorinate

  18. Chlorine Gas: An Evolving Hazardous Material Threat and Unconventional Weapon

    Directory of Open Access Journals (Sweden)

    Jones, Robert MD

    2010-05-01

    Full Text Available Chlorine gas represents a hazardous material threat from industrial accidents and as a terrorist weapon. This review will summarize recent events involving chlorine disasters and its use by terrorists, discuss pre-hospital considerations and suggest strategies for the initial management for acute chlorine exposure events. [West J Emerg Med. 2010; 11(2:151-156.

  19. Sprinkler irrigation-pesticide best management systems

    OpenAIRE

    Ranjha, A. Y.; Peralta, R. C.; Hill, R. W.; Requena, A. M.; Deer, H. M.; Ehteshami, M.

    1992-01-01

    The relative reduction in potential groundwater contamination due to pesticides at several sites in Utah was determined by comparing alternative irrigation system designs, water management practices, and pesticides. Alternative sprinkler irrigation distribution coefficients were used to estimate irrigation application depths. The movement of pesticides through soils following sprinkler irrigations was simulated with a one-dimensional model. Pesticide contamination of groundwater can be reduce...

  20. Fact Sheets on Pesticides in Schools.

    Science.gov (United States)

    National Coalition against the Misuse of Pesticides, Washington, DC.

    This document consists of a collection of fact sheets about the use of pesticides in schools and how to reduce it. The sheets are: (1) "Alternatives to Using Pesticides in Schools: What Is Integrated Pest Management?"; (2) "Health Effects of 48 Commonly Used Pesticides in Schools"; (3) "The Schooling of State Pesticide Laws--2002 Update: A Review…

  1. Pesticide Productivity: Of Bugs and Biases

    OpenAIRE

    Norwood, F. Bailey; Marra, Michele C.

    2003-01-01

    Pesticide productivity is both important and difficult to measure. Typically, pesticide marginal products are estimated without information on the pest pressure. Three theoretical models are developed which suggest absence of such information may cause an underestimation of pesticide productivity. Using application frequency variables as a proxy for pest populations, we show that pesticide marginal products are higher when pest pressure is accounted for.

  2. Chlorination of nickel ore by gaseous chlorine in the presence of active additives

    Directory of Open Access Journals (Sweden)

    Ilić Ilija B.

    2003-01-01

    Full Text Available Paper presents a thermodynamic analysis of chemical reactions occurring during chlorination with and without additives for both nickel oxides and nickel ferrites, which are component parts of nickel ore. The experimental research investigated the influence of temperature in the range from 600 up to 1000 °C and time (up to 3 h on the chlorination degree of nickel ores with and without additives. It was found that the introduction of additives such as C, S, BaS and NaCl intensified the chlorination of nickel ore. The results can be applied and may help determine the optimal conditions for the chlorination of low-grade ferrous nickel ores.

  3. Soil column leaching of pesticides.

    Science.gov (United States)

    Katagi, Toshiyuki

    2013-01-01

    In this review, I address the practical and theoretical aspects of pesticide soil mobility.I also address the methods used to measure mobility, and the factors that influence it, and I summarize the data that have been published on the column leaching of pesticides.Pesticides that enter the unsaturated soil profile are transported downwards by the water flux, and are adsorbed, desorbed, and/or degraded as they pass through the soil. The rate of passage of a pesticide through the soil depends on the properties of the pesticide, the properties of the soil and the prevailing environmental conditions.Because large amounts of many different pesticides are used around the world, they and their degradates may sometimes contaminate groundwater at unacceptable levels.It is for this reason that assessing the transport behavior and soil mobility of pesticides before they are sold into commerce is important and is one indispensable element that regulators use to assess probable pesticide safety. Both elementary soil column leaching and sophisticated outdoor lysimeter studies are performed to measure the leaching potential for pesticides; the latter approach more reliably reflects probable field behavior, but the former is useful to initially profile a pesticide for soil mobility potential.Soil is physically heterogeneous. The structure of soil varies both vertically and laterally, and this variability affects the complex flow of water through the soil profile, making it difficult to predict with accuracy. In addition, macropores exist in soils and further add to the complexity of how water flow occurs. The degree to which soil is tilled, the density of vegetation on the surface, and the type and amounts of organic soil amendments that are added to soil further affect the movement rate of water through soil, the character of soil adsorption sites and the microbial populations that exist in the soil. Parameters that most influence the rate of pesticide mobility in soil are

  4. Chlorinated organic compounds in urban river sediments

    Energy Technology Data Exchange (ETDEWEB)

    Soma, Y.; Shiraishi, H.; Inaba, K. [National Inst. of Environmental Studies, Tsukuba, Ibaraki (Japan)

    1995-12-31

    Among anthropogenic chemicals, many chlorinated organic compounds have been used as insecticides and detected frequently as contaminants in urban river sediments so far. However, the number and total amount of chemicals produced commercially and used are increasing year by year, though each amount of chemicals is not so high. New types of contaminants in the environment may be detected by the use of newly developed chemicals. Chlorinated organic compounds in the urban river sediments around Tokyo and Kyoto, large cities in Japan, were surveyed and recent trends of contaminants were studied. Contaminants of the river sediments in industrial areas had a variety, but PCB (polychlorinated biphenyls) was detected in common in industrial areas. Concentration of PCB related well to the number of factories on both sides of rivers, although the use of PCB was stopped 20 years ago. In domestic areas, Triclosan (5-chloro-2-(2,4-dichlorophenoxy)-phenol) and Triclocarban (3,4,4{prime}-trichlorocarbanilide)(both are contained in soap or shampoo for fungicides), p-dichlorobenzene (insecticides for wears) and TCEP(tris-chloroethyl phosphate) were detected. EOX(extracted organic halogen) in the sediments was 5 to 10 times of chlorinated organic compounds detected by GC/MS. Major part of organic halogen was suggested to be included in chlorinated organics formed by bleaching or sterilization.

  5. 46 CFR 151.50-31 - Chlorine.

    Science.gov (United States)

    2010-10-01

    ... desired rate of discharge, provided the air or gas is oil-free and thoroughly dried by passing it over activated aluminum oxide, silica gel, or other acceptable drying agent, and provided the supply pressure is...-resistant to chlorine in either the gas or liquid phase. Cast or malleable iron shall not be used....

  6. Chlorinated tyrosine derivatives in insect cuticle

    DEFF Research Database (Denmark)

    Andersen, Svend Olav

    2004-01-01

    , not-yet sclerotized cuticle of adult femur and tibia, the amounts increased rapidly during the first 24 h after ecdysis and more slowly during the next two weeks. Control analyses using stable isotope dilution mass spectrometry have confirmed that the chlorinated tyrosines are not artifacts formed...

  7. Field-usable portable analyzer for chlorinated organic compounds. Topical report, September 1992--May 1994

    Energy Technology Data Exchange (ETDEWEB)

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

    1995-05-01

    Through a U.S. DOE-funded program, an advanced chlorinated organic (RCL) vapor monitor has been built and tested in actual hazardous waste site operations. The monitor exploits the analytical capabilities of a solid-state sensor which was recently developed and has remarkable selectivity for chlorinated organic vapors at sub-parts-per-million sensitivity. The basic design goal of a user-friendly, reliable, instrument with a broad dynamic range for the selective detection of chlorinated solvent vapors was demonstrated. To date, no non-halogen-containing compound has been identified that induces a measurable response on the sensor, including commonly encountered contaminants such as BTXs (benzene, toluene, and xylenes) or POLs (petroleum, oils, lubricants). In addition to the development of the RCL MONITOR, advanced sampler systems were developed to further extend the analytical capability of this instrument, allowing chemical analyses to be performed for both vapor phase and condensed contamination. The sampling methods include fixed dilution, preconcentration, and closed-loop air stripping for condensed media. With uniform success, these different series of field tests were conducted at DOE facilities on several types of samples. Independent cost-benefit analysis has concluded that significant cost savings can be achieved using the RCL MONITOR in DOE applications. This effort provides a sound fundamental technology base for the development of advanced analytical methods that are needed by the US DOE. In addition, advanced methods for detecting chlorinated hydrocarbons that are made possible by this technology will save time, reduce costs, and improve human health and safety in restoration operations. To fully achieve all possible cost savings, continued effort is necessary to develop validated methods for the use of the RCL MONITOR. The development of methods through case studies is the theme of the Phase II effort, which is currently underway.

  8. Halogenated volatile organic compounds from the use of chlorine-bleach-containing household products.

    Science.gov (United States)

    Odabasi, Mustafa

    2008-03-01

    Sodium hypochlorite (NaOCl) and many organic chemicals contained in household cleaning products may react to generate halogenated volatile organic compounds (VOCs). Halogenated VOC emissions from eight different chlorine bleach containing household products (pure and diluted) were investigated by headspace experiments. Chloroform and carbon tetrachloride were the leading compounds along with several halogenated compounds in the headspace of chlorine bleach products. One of the most surprising results was the presence of carbon tetrachloride (a probable human carcinogen and a powerful greenhouse gas that was banned for household use by the U.S. Food and Drug Administration) in very high concentrations (up to 101 mg m(-3)). By mixing surfactants or soap with NaOCl, it was shown that the formation of carbon tetrachloride and several other halogenated VOCs is possible. In addition to quantitatively determined halogenated VOCs (n = 15), several nitrogen-containing (n = 4), chlorinated (n = 10), oxygenated compounds (n = 22), and hydrocarbons (n = 14) were identified in the headspace of bleach products. Among these, 1,1-dichlorobutane and 2-chloro-2-nitropropane were the most abundant chlorinated VOCs, whereas trichloronitromethane and hexachloroethane were the most frequently detected ones. Indoor air halogenated VOC concentrations resulting from the use of four selected household products were also measured before, during, and 30 min after bathroom, kitchen, and floor cleaning applications. Chloroform (2.9-24.6 microg m(-3)) and carbon tetrachloride (0.25-459 microg m(-3)) concentrations significantly increased during the use of bleach containing products. During/ before concentration ratios ranged between 8 and 52 (25 +/- 14, average +/- SD) for chloroform and 1-1170 (146 +/- 367, average +/- SD) for carbon tetrachloride, respectively. These results indicated that the bleach use can be important in terms of inhalation exposure to carbon tetrachloride, chloroform and

  9. Cellular Response of the Amoeba Acanthamoeba castellanii to Chlorine, Chlorine Dioxide, and Monochloramine Treatments ▿

    OpenAIRE

    Mogoa, Emerancienne; Bodet, Charles; Morel, Franck; Rodier, Marie-Hélène; Legube, Bernard; Héchard, Yann

    2011-01-01

    Acanthamoeba castellanii is a free-living amoebae commonly found in water systems. Free-living amoebae might be pathogenic but are also known to bear phagocytosis-resistant bacteria, protecting these bacteria from water treatments. The mode of action of these treatments is poorly understood, particularly on amoebae. It is important to examine the action of these treatments on amoebae in order to improve them. The cellular response to chlorine, chlorine dioxide, and monochloramine was tested o...

  10. Anaerobic biodegradability and toxicity of wastewaters from chlorine and total chlorine-free bleaching of eucalyptus kraft pulps.

    NARCIS (Netherlands)

    Vidal, G.; Soto, M.; Field, J.; Mendez-Pampin, R.; Lema, J.M.

    1997-01-01

    Chlorine bleaching effluents are problematic for anaerobic wastewater treatment due to their high methanogenic toxicity and low biodegradability. Presently, alternative bleaching processes are being introduced, such as elemental chlorine-free (ECF) and total chlorine-free (TCF) bleaching. The methan

  11. Application of the Raman spectroscopy for the characterization of organic pesticides; Aplicacion de la espectroscopia Raman para la caracterizacion de pesticidas organicos

    Energy Technology Data Exchange (ETDEWEB)

    Sato B, R.Y.; Medina G, C.; Medina V, J.; Frausto R, C. [Centro de Investigaciones en Optica, A.C., Unidad Aguascalientes, Prol. Constitucion 607, Reserva Loma Bonita, C.P. 20200, Aguascalientes (Mexico)]. e-mail: rsato@foton.cio.mx

    2004-07-01

    Raman spectra of organophosphate, organo chlorine and bipyridyl pesticides are presented in this study. They have been obtained satisfactorily by the NlR-Raman spectroscopy technique. Pesticides have been analyzed in solution or as a solid in glass containers and on aluminum substrates. This analytic technique can be an alternative tool for the detection of pesticides in the agriculture, presenting advantages as be quick, not destructive and require little or no sample preparation. Moreover, samples can be analyzed through transparent containers avoiding contact with the toxic substances. The implementation of the aluminium substrate is easy and practical. Moreover, it is commercially available and does not need a previous preparation. The analysis of a mixture of two pesticides in a {beta} carotene solution is shown. (Author) 25 refs., 8 figs.

  12. HYDROCARBONS DIAGNOSTIC OF POLLUTED SOILS

    Directory of Open Access Journals (Sweden)

    Mohamed Arad

    2010-12-01

    Full Text Available Petroleum hydrocarbons are known as carcinogenic and may contaminate the environment (water, air and soil. In this study, a diagnostic of polluted soils by petroleum hydrocarbons is carried out in order to know the effect of their accumulation as well as their behavior in time. The aging factor, a source of significant changing in hydrocarbon behavior, is integrated on two sites of an industrial refinery as experimental samples. The first site is recently polluted by hydrocarbons while the second is a previously polluted site.The results indicate that the concentration of hydrocarbons on the surface of the first site is greater and remains stable in time, as for the second site, hydrocarbons concentration on the surface is also important and undergoes a weak reduction. At a depth of one meter hydrocarbons exist at a greater concentration. This shows that obstinate hydrocarbons are an environmental danger for fauna and flora.

  13. 75 FR 13284 - Pesticide Program Dialogue Committee; Request for Nominations to the Pesticide Program Dialogue...

    Science.gov (United States)

    2010-03-19

    ... AGENCY Pesticide Program Dialogue Committee; Request for Nominations to the Pesticide Program Dialogue Committee AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: Pursuant to the Federal Advisory Committee Act, EPA's Office of Pesticide Programs is inviting nominations of qualified...

  14. Halogenase-Inspired Oxidative Chlorination Using Flavin Photocatalysis.

    Science.gov (United States)

    Hering, Thea; Mühldorf, Bernd; Wolf, Robert; König, Burkhard

    2016-04-18

    Chlorine gas or electropositive chlorine reagents are used to prepare chlorinated aromatic compounds, which are found in pharmaceuticals, agrochemicals, and polymers, and serve as synthetic precursors for metal-catalyzed cross-couplings. Nature chlorinates with chloride anions, FAD-dependent halogenases, and O2 as the oxidant. A photocatalytic oxidative chlorination is described based on the organic dye riboflavin tetraacetate mimicking the enzymatic process. The chemical process allows within the suitable arene redox potential window a broader substrate scope compared to the specific activation in the enzymatic binding pocket.

  15. Determination of levels of organochlorine pesticides in plastic resin pellets on selected beaches in the Greater Accra region of Ghana

    International Nuclear Information System (INIS)

    The levels of organochlorine pesticides (OCPs) in beached plastic resin pellets were determined with the objective of assessing the status of OCP pollution in the marine ecosystem in selected beaches in Ghana. Samples of plastic resin pellets were collected at seven beaches in Accra (namely Art centre, Sakumono, Osu castle, Labadi, Korle-Gonno, Independence Square and Tema Mighty beaches) and analyzed for organochlorine pesticides, total chlorine and extractable chlorine. The plastic pellets were subjected to Soxhlet extraction and the extracts analyzed using Gas chromatograph coupled with electron capture detector. The detected compounds were alpha-HCH, beta-HCH, gamma-HCH, delta-HCH, hexachlorobenzene, o, p' -DDE, p, p'-DDE, o,p'-DDD, o, p'-DDT, heptachlor, trans-heptachlor epoxy, trans-chlordane, trans-nanochlor, aldrin, dieldrin, endrin, alpha-endosulphan, beta-endosulphan, endosulphan sulphate and methoxychlor. Analysis of the virgin pellets recorded no organochlorine pesticides present. However, plastics pellets collected from all seven beaches were found to contain OCPs with the highest recorded on the Art Centre beach with a total concentration of 106.26 ng/g. Plastic pellets collected on the Labadi beach recorded the lowest OCPs with a concentration of 20.2 ng/g. Total chlorine and extractable organochlorine (EOCI) were also determined in the plastic resin pellets by using the Instrumental Neutron Activation Analysis (INAA). The concentrations of total chlorine analyzed by INAA were between 2.82 and 50.25 mg/kg whereas the EOCR concentrations ranged from 1.67 to 30.90 mg/kg. EOCR accounted for 48.05% of the total chlorine in plastic pellets, suggesting that chlorine in the beached pellet relatively existed as organic and are extractable. The relative proportion of known or identified organochlorines (such as HCHs, DDT s, chlordane compounds, endosulphans, HCB and methoxychlor) to the total extractable organochlorine(EOCI) was averagely 7.4% which suggested

  16. Pesticide use and application: An Indian scenario

    Energy Technology Data Exchange (ETDEWEB)

    Abhilash, P.C., E-mail: pcabhilash@gmail.com [Eco-Auditing Group, National Botanical Research Institute, Council of Scientific and Industrial Research, Rana Pratap Marg, Lucknow 226001, Uttar Pradesh (India); Singh, Nandita, E-mail: nanditasingh8@yahoo.co.in [Eco-Auditing Group, National Botanical Research Institute, Council of Scientific and Industrial Research, Rana Pratap Marg, Lucknow 226001, Uttar Pradesh (India)

    2009-06-15

    Agricultural development continues to remain the most important objective of Indian planning and policy. In the process of development of agriculture, pesticides have become an important tool as a plant protection agent for boosting food production. Further, pesticides play a significant role by keeping many dreadful diseases. However, exposure to pesticides both occupationally and environmentally causes a range of human health problems. It has been observed that the pesticides exposures are increasingly linked to immune suppression, hormone disruption, diminished intelligence, reproductive abnormalities and cancer. Currently, India is the largest producer of pesticides in Asia and ranks twelfth in the world for the use of pesticides. A vast majority of the population in India is engaged in agriculture and is therefore exposed to the pesticides used in agriculture. Although Indian average consumption of pesticide is far lower than many other developed economies, the problem of pesticide residue is very high in India. Pesticide residue in several crops has also affected the export of agricultural commodities in the last few years. In this context, pesticide safety, regulation of pesticide use, proper application technologies, and integrated pest management are some of the key strategies for minimizing human exposure to pesticides. There is a dearth of studies related to these issues in India. Therefore, the thrust of this paper was to review the technology of application of pesticides in India and recommend future strategies for the rational use of pesticides and minimizing the problems related to health and environment.

  17. Radiation induced pesticidal microbes

    International Nuclear Information System (INIS)

    To isolate pesticidal microbes against plant pathogenic fungi, 4 strains of bacteria(K1. K3, K4, YS1) were isolated from mushroom compost and hot spring. K4, K1, K3, YS1 strain showed wide antifungal spectrum and high antifungal activities against 12 kinds of fungi. Specific proteins and the specific transcribed genes were found from the YS1 and its radiation-induced mutants. And knock-out mutants of antifungal activity were derived by transposon mutagenesis. From these knock-out mutants, the antifungal activity related genes and its modification by gamma-ray radiation are going to be studied. These results suggested that radiation could be an useful tool for the induction of functional mutants

  18. Pesticide reducing instruments

    DEFF Research Database (Denmark)

    Jacobsen, Lars-Bo; Jensen, Jørgen Dejgård; Andersen, Martin;

    2005-01-01

    the cost and to calculate general economic and sectoral consequences. This CGE model is linked to an agricultural sector model calculating the optimal use of land, and the agricultural sector model is then linked to a biological agent based simulation model (ABM) calculating changes in the population......-mentioned models and tools. All three scenarios are constructed such that they result in the same welfare implication (measured by national consumption in the CGE model). The scenarios are: 1) pesticide taxes resulting in a 25 percent overall reduction; 2) use of unsprayed field margins, resulting in the same...... for improving bio-diversity and securing drinking water. That is, combining economic modeling with physical biological modeling and geological evaluation allows us to select unsprayed field margins as the most effective instrument. Sensitivity analysis conducted on bio-diversity suggest that this result...

  19. Radiation induced pesticidal microbes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Yup; Lee, Y. K.; Kim, J. S.; Kim, J. K.; Lee, S. J.; Lim, D. S

    2001-01-01

    To isolate pesticidal microbes against plant pathogenic fungi, 4 strains of bacteria(K1. K3, K4, YS1) were isolated from mushroom compost and hot spring. K4, K1, K3, YS1 strain showed wide antifungal spectrum and high antifungal activities against 12 kinds of fungi. Specific proteins and the specific transcribed genes were found from the YS1 and its radiation-induced mutants. And knock-out mutants of antifungal activity were derived by transposon mutagenesis. From these knock-out mutants, the antifungal activity related genes and its modification by gamma-ray radiation are going to be studied. These results suggested that radiation could be an useful tool for the induction of functional mutants.

  20. HYDROCARBONS DIAGNOSTIC OF POLLUTED SOILS

    OpenAIRE

    Mohamed Arad; Abdelkader Anouzla; Mohamed Safi; Salah Souabi; Hicham Rhbal

    2010-01-01

    Petroleum hydrocarbons are known as carcinogenic and may contaminate the environment (water, air and soil). In this study, a diagnostic of polluted soils by petroleum hydrocarbons is carried out in order to know the effect of their accumulation as well as their behavior in time. The aging factor, a source of significant changing in hydrocarbon behavior, is integrated on two sites of an industrial refinery as experimental samples. The first site is recently polluted by hydrocarbons while the s...

  1. Selecting hydrocarbon rocket propulsion technology

    Science.gov (United States)

    Martin, J. A.

    1986-01-01

    Past studies have shown that the dry weight of future earth-to-orbit vehicles can be reduced by the combined use of hydrogen and hydrocarbon propulsion compared to all-hydrogen propulsion. This paper shows that the use of certain hydrocarbon engines with hydrogen engines produces the lowest vehicle dry mass. These hydrocarbon engines use propane or RP-1 fuel, hydrogen cooling, and hydrogen-rich gas generators. Integration of the hydrogen and hydrocarbon nozzles is also beneficial.

  2. The use of radioisotopes 32P and 35S in studies on behavior of pesticides in the soil

    International Nuclear Information System (INIS)

    Radioisotopes were used to determine the possibility and extent of contamination of underground waters by pesticides used in agriculture. The sorption and dynamics of the migration of two organo-phosphorous pesticides, fenitrothion and malathion, were studied. These two products are currently being proposed as agricultural pesticides. They would replace other substances of the chrlorinated hydrocarbon group, including DDT, which are more dangerous to health, but are themselves source of potential contamination of underground waters. Studies were carried out on different types of soil: sandy and clay. Isotherms were determined for the sorption of the pesticides examined, together with their distribution coefficients, Kd. The effects of pH values, exchangeable ions, organic substances (organic C and N) and the mechanical composition of the sorption of fenitrothion and malathion were studied

  3. Database of Pesticides and Off-flavors for Health Crisis Management.

    Science.gov (United States)

    Ueda, Yasuhito; Itoh, Mitsuo

    2016-01-01

    In this experiment, 351 pesticides and 441 different organic compounds were analyzed by GC/MS, and a database of retention time, retention index, monoisotopic mass, two selected ions, molecular formula, and CAS numbers was created. The database includes compounds such as alcohols, aldehydes, carboxylic acids, esters, ethers and hydrocarbons with unpleasant odors. This database is expected to be useful for health crisis management in the future. PMID:27211918

  4. Younger age at onset of sporadic Parkinson's disease among subjects occupationally exposed to metals and pesticides

    OpenAIRE

    Ratner Marcia H.; Farb David H.; Ozer Josef; Feldman Robert G.; Durso Raymon

    2014-01-01

    An earlier age at onset of Parkinson’s disease (PD) has been reported to be associated with occupational exposures to manganese and hydrocarbon solvents suggesting that exposure to neurotoxic chemicals may hasten the progression of idiopathic PD. In this study the role of occupational exposure to metals and pesticides in the progression of idiopathic PD was assessed by looking at age at disease onset. The effects of heritable genetic risk factors, which may also influence age at onset, was mi...

  5. Metals elements and chlorinated compounds in cetaceans; Elementi metallici e composti organoclorurati in cetacei

    Energy Technology Data Exchange (ETDEWEB)

    Cardellicchio, N. [Consiglio Nazionale delle Ricerche. Ist. Sperimentale Talassografico, Taranto (Italy)

    1997-01-01

    Non-degradable pollutants determination in cetacea, high tropic level organisms, represents an evaluating element both for bioaccumulation phenomena and sea ecosystem quality. In this paper is shown determination results for metals, chlorinated pesticides, and polychlorinated biphenyls (PCB) in Stenella coeruleoalba specimens, beached along the coast of Puglia (Italy), in the period February-June 1987. Chemical-toxicological surveys verified that in there Mediterranean marine mammals pollutant accumulation is higher than in Atlantic species. Lipophylous toxical compounds transferred from mothers to offspring represents a high risk for their survival. even though this survey failed to establish a direct cause-effect relationship between pollutant levels and anatomical-pathological lesions, it is apparent that sea pollution phenomena are reflected negatively in the top of the food chains.

  6. Toxic effects of chlorinated cake flour in rats.

    Science.gov (United States)

    Cunningham, H M; Lawrence, G A; Tryphonas, L

    1977-05-01

    Four experiments were conducted using weanling Wistar rats to determine whether chlorinated cake flour or its constituents were toxic. Levels of 0.2 and 1.0% chlorine added to unbleached cake flour significantly (p less than 0.01) reduced growth rate by 20.7 and 85.2% and increased liver weight relative to body weight by 16.7 and 25.3%, respectively. Lipids extracted from flour chlorinated at the same levels had similar effects. Rat chow diets containing 0.2 and 0.6% chlorine in the form of chlorinated wheat gluten reduced growth rate and increased liver weight as a percentage of body weight. A rat chow diet containing 0.2% chlorine as chlorinated flour lipids increased absolute liver weight by 40%, kidney by 20%, and heart by 10% compared to pair-fed controls. PMID:864787

  7. 77 FR 64990 - Pesticide Program Dialogue Committee; Request for Nominations to the Pesticide Program Dialogue...

    Science.gov (United States)

    2012-10-24

    ... groups; pesticide users and growers; animal rights groups; pest consultants; State, local, and tribal...: Environmental/public interest and animal rights groups; farm worker organizations; pesticide industry and...

  8. Relation between chlorine with the quality of crude water

    International Nuclear Information System (INIS)

    Chlorine as disinfection agent in drinking water was used widely since it was successfully been practiced in drinking water in Jersey City, 1908. Mostly, water treatment plants in Malaysia were using chlorine as disinfection agent to kill pathogen and contaminated materials that can be dangerous to consumer. Because of chlorine was a strongly disinfection agent, it also can react with another chemical components such as manganese, hydrogen, sulfides, ammonia and phenol in water. These reactions happen very fast, and chlorine will not react as disinfection agent unless all the organic and inorganic substitution presented in water reacts with chlorine. These reactions between components will increase demand of chlorine in water. The demand of chlorine in water must be filled before the free radical chlorine occurred. These free radical chlorine will decay into hypochlorous acid and hypochlorite ion that so important in disinfection process to kill pathogens and pollutants in water. Most of water treatment plant to maintain free chlorine up to 0.2 mg/ L in distribution system to consumer. These researches involved determination of parameters that can be trusted to react with the chlorine in nine sampling station along Semenyih River and four stations in water treatment plants. These parameters were determined from ammonia, cyanides, sulfides, phenol, phosphorus, nitrite, manganese, iron and sum of organic carbons. Overall, these researches concluded that ammonia and sum of organic carbons were the most compounds that react with the chlorine to produce tryhalometane and chloramines. Besides that, the concentration of cyanides compounds, sulfide, phenol, phosphorus, nitrite, manganese and iron also decrease after the chlorination process. Results can used to evaluate demanding levels of chlorine in Semenyih River. (author)

  9. Apparatus and methods for hydrocarbon extraction

    Energy Technology Data Exchange (ETDEWEB)

    Bohnert, George W.; Verhulst, Galen G.

    2016-04-26

    Systems and methods for hydrocarbon extraction from hydrocarbon-containing material. Such systems and methods relate to extracting hydrocarbon from hydrocarbon-containing material employing a non-aqueous extractant. Additionally, such systems and methods relate to recovering and reusing non-aqueous extractant employed for extracting hydrocarbon from hydrocarbon-containing material.

  10. Pesticide movement and water management

    OpenAIRE

    Ehteshami, Majid; Peralta, R C

    1989-01-01

    Agricultural chemicals are essential components of agricultural production systems in the United states. Pesticides control weeds, insects, and have had an important role in increasing agricultural productivity in the last 50 years, despite diminishing crop land acreage. The benefits of chemicals use options in agriculture must be balanced against potential contamination of surface water and ground water resources. This study shows the effect of water management practices on pesticide movemen...

  11. Pesticidal residues in animal tissues

    Science.gov (United States)

    DeWitt, J.B.; Menzie, C.M.; Adomaitis, V.A.; Reichel, W.L.

    1960-01-01

    Tests with penned starlings, rats, pheasants, and ducks indicated that each species differs in sensitivity to the various pesticides. Residues in tissues are proportional to the degree of exposure during area treatment and they are also found in animals shot six or more months after treatment. The presence of more than 20-30 ppm of DDT, 20 ppm of chlordan, and 6-20 ppm of heptachlor epoxide in quail tissues indicated that the birds had ingested lethal dosages of the pesticides.

  12. Occurrence Of Pesticides In Surface And Groundwater In Two Catchments On Sjælland, Denmark

    DEFF Research Database (Denmark)

    McKnight, Ursula S.; Rasmussen, Jes J.; Kronvang, Brian;

    2011-01-01

    The release of chemicals such as chlorinated solvents, pesticides and other xenobiotic organic compounds to streams, either from contaminated sites, accidental or direct application/ release, is a significant threat to water resources. Fulfilling the requirements of the EU Water Framework Directive...... – and ideally separate – potential stressors acting on surface water ecosystems at the catchment-scale. A secondary objective was to evaluate possible water quality differences between site types (distinguished as first-order stream locations potentially impacted by a single stressor) and seasons....

  13. Antiradiation effectiveness of the chlorine C

    International Nuclear Information System (INIS)

    At present ever more attention of the experimenters in the field of search of high-effective antiray means - is directed to development of preparations from bio-active substances of a natural origin. In this connection all greater interest is caused by researches of antiray activity of these compounds, distinguished, as a rule, from known preparations of synthetic manufacture of low toxicity, absence of expressed collateral effects and possibility of course application. It has biological (antiray) activity in dozes 5-10 mg/kg and chlorine C which is derivative of chlorophil A. At present it passes tests in oncology. Porphyrines (synthetic and natural) are recently subjected to wide study as potential medicinal means, due to their ability to be accumulated in bodies of the reticulo-endothelial system and proliferous tissues, as well as their physical-chemical characteristics (fluorescence, photosensitizing action, colouring). All this testifies for the benefit of perspective use of porphyrin for treatment and diagnostics of tumors. According to the above described properties of porphyrines there is that fact, that for some of them radioprotective properties are revealed during the injections as well as before and after radiation treatment. The above said has formed the basis for study of antiray properties of the chlorine C during the experiments on small-sized laboratory animals. Antiradiation effectivity of chlorine C was studied on the mice (CBA x C57 B1) F1. Chlorine C was applied in a wide range of dozes with its' use in 3 variants: before radiation treatment, after radiation treatment, combined (before and after radiation treatment). Radioprotective activity of chlorine C reduces at an increase of a time of the injection before radiation treatment and at other ways of injection (intramuscularly, subcutaneously, per os). Studies of medical activity of chlorine C in experiments on mice have shown, that the compound does not possess medical activity. The death of

  14. Oxidative elimination of cyanotoxins: comparison of ozone, chlorine, chlorine dioxide and permanganate.

    Science.gov (United States)

    Rodríguez, Eva; Onstad, Gretchen D; Kull, Tomas P J; Metcalf, James S; Acero, Juan L; von Gunten, Urs

    2007-08-01

    As the World Health Organization (WHO) progresses with provisional Drinking Water Guidelines of 1 microg/L for microcystin-LR and a proposed Guideline of 1 microg/L for cylindrospermopsin, efficient treatment strategies are needed to prevent cyanotoxins such as these from reaching consumers. A kinetic database has been compiled for the oxidative treatment of three cyanotoxins: microcystin-LR (MC-LR), cylindrospermopsin (CYN), and anatoxin-a (ANTX) with ozone, chlorine, chlorine dioxide and permanganate. This kinetic database contains rate constants not previously reported and determined in the present work (e.g. for permanganate oxidation of ANTX and chlorine dioxide oxidation of CYN and ANTX), together with previously published rate constants for the remaining oxidation processes. Second-order rate constants measured in pure aqueous solutions of these toxins could be used in a kinetic model to predict the toxin oxidation efficiency of ozone, chlorine, chlorine dioxide and permanganate when applied to natural waters. Oxidants were applied to water from a eutrophic Swiss lake (Lake Greifensee) in static-dose testing and dynamic time-resolved experiments to confirm predictions from the kinetic database, and to investigate the effects of a natural matrix on toxin oxidation and by-product formation. Overall, permanganate can effectively oxidize ANTX and MC-LR, while chlorine will oxidize CYN and MC-LR and ozone is capable of oxidizing all three toxins with the highest rate. The formation of trihalomethanes (THMs) in the treated water may be a restriction to the application of sufficiently high-chlorine doses.

  15. Use of pesticides in Kazakhstan

    International Nuclear Information System (INIS)

    The Republic of Kazakhstan has 210 regional stations, 19 provincial stations and one co-ordinating government research and production station, all known as Republic Stations for Plant Protection. These stations have the following functions: they control pesticide use and development, and monitor pest populations; they inform and teach farmers the methods for controlling insect pests, diseases and weeds, and the rules for safe pesticide use; and they continually monitor the presence or spread of any adverse effects in order to make short and long term prognoses, which are then used to determine the pesticide requirements. The major functions of these government stations is to control the timely distribution of pesticides and their safe and timely application, so that regulations for their use can be monitored and control over technology maintained. The co-ordinating station evaluates all projects, provides documentation on the use and storage of pesticides, controls field trials carried out by foreign companies on the Republic's territory and regulates pesticide usage during campaigns against insect pests, diseases and weeds. The regional and district subdivisions of these government stations promote integrated pest management for protecting harvests. (author)

  16. Pesticides' influence on wine fermentation.

    Science.gov (United States)

    Caboni, Pierluigi; Cabras, Paolo

    2010-01-01

    Wine quality strongly depends on the grape quality. To obtain high-quality wines, it is necessary to process healthy grapes at the correct ripeness stage and for this reason the farmer has to be especially careful in the prevention of parasite attacks on the grapevine. The most common fungal diseases affecting grape quality are downy and powdery mildew (Plasmopara viticola and Uncinula necator), and gray mold (Botrytis cinerea). On the other hand, the most dangerous insects are the grape moth (Lobesia botrana), vine mealybug (Planococcus ficus), and the citrus mealybug (Planococcus citri). Farmers fight grape diseases and insects applying pesticides that can be found at harvest time on grapes. The persistence of pesticides depends on the chemical characteristic of the active ingredients as well as on photodegradation, thermodegradation, codistillation, and enzymatic degradation. The pesticide residues on grapes can be transferred to the must and this can influence the selection and development of yeast strains. Moreover, yeasts can also influence the levels of the pesticides in the wine by reducing or adsorbing them on lees. During the fermentative process, yeasts can cause the disappearance of pesticide residues by degradation or absorption at the end of the fermentation when yeasts are deposited as lees. In this chapter, we reviewed the effect of commonly used herbicides, insecticides, and fungicides on yeasts. We also studied the effect of alcoholic and malolactic fermentation on pesticide residues.

  17. Pesticides' influence on wine fermentation.

    Science.gov (United States)

    Caboni, Pierluigi; Cabras, Paolo

    2010-01-01

    Wine quality strongly depends on the grape quality. To obtain high-quality wines, it is necessary to process healthy grapes at the correct ripeness stage and for this reason the farmer has to be especially careful in the prevention of parasite attacks on the grapevine. The most common fungal diseases affecting grape quality are downy and powdery mildew (Plasmopara viticola and Uncinula necator), and gray mold (Botrytis cinerea). On the other hand, the most dangerous insects are the grape moth (Lobesia botrana), vine mealybug (Planococcus ficus), and the citrus mealybug (Planococcus citri). Farmers fight grape diseases and insects applying pesticides that can be found at harvest time on grapes. The persistence of pesticides depends on the chemical characteristic of the active ingredients as well as on photodegradation, thermodegradation, codistillation, and enzymatic degradation. The pesticide residues on grapes can be transferred to the must and this can influence the selection and development of yeast strains. Moreover, yeasts can also influence the levels of the pesticides in the wine by reducing or adsorbing them on lees. During the fermentative process, yeasts can cause the disappearance of pesticide residues by degradation or absorption at the end of the fermentation when yeasts are deposited as lees. In this chapter, we reviewed the effect of commonly used herbicides, insecticides, and fungicides on yeasts. We also studied the effect of alcoholic and malolactic fermentation on pesticide residues. PMID:20610173

  18. PCBs and chlorinated pesticides in adult male Polar Bears (Ursus maritimus) from Alaska

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Persistent organochlorines (OC) contaminants, including polychlorinated biphenyls (PCB) congeners, Dichlorophenyltrichloroethane (DDT) and its metabolites including...

  19. Comparative efficacy of chlorine and chlorine dioxide regimes for condenser slime control in seawater cooled heat exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Murthy, P.S.; Veeramani, P.; Ershath, M.; Rajamohan, R.; Harinath, Y.V.; Mohan, T.V.K.; Venugopalan, V.P. [BARC Facilities, Water and Steam Chemistry Div., Kalpakkam, Tamil nadu (India)

    2010-07-01

    Chlorination has long been used as an effective and economic biocide for biofouling control in seawater cooling systems. However, the efficacy of chlorine is reduced in the presence of organic content of seawater and the inability of chlorine to effectively penetrate biofilms. Chlorine dioxide is being projected as a possible alternative to chlorine. Experiments were carried out with the help of a seawater circulating facility, in which direct comparison of the efficacy of the two biocides was possible using test condenser tube assemblies. The test condenser tubes made of titanium, SS 316L and Cu-Ni 90/10 were dosed with chlorine and chlorine dioxide. Each dose was evaluated for 30 days. Continuous and intermittent additions of chlorine (0.38 - 0.45 mg L{sup -1} TRO) and chlorine dioxide (0.4 - 0.5 mg L{sup -1}) were used, along with control. The flow velocity in the tubes was maintained at 1.5 m/s. Results of the study showed that the efficacy of the biocide to control biofilms depended on the biocide and the material. Continuous chlorination resulted in 75% reduction of viable counts on titanium, followed by 24% reduction on CuNi and 6% reduction on SS 316L surfaces, as compared to the control. When compared to continuous chlorination, increase in bacterial density in the tubes was observed at different regimes of intermittent chlorination. On SS 316L and Cu-Ni surfaces, intermittent chlorination for 1h, once every 3 h, appeared to give adequate protection. Continuous addition of chlorine dioxide resulted in 99% reduction of viable counts on titanium surfaces, followed by 28% reduction on SS 316 L surfaces and 52% reduction on Cu-Ni surfaces, as compared to the controls. The data indicate that the efficacy of biocides to control biofilms depend on not only the biocide and its frequency of application but also the material of construction. (author)

  20. Comparative efficacy of chlorine and chlorine dioxide regimes for condenser slime control in seawater cooled heat exchangers

    International Nuclear Information System (INIS)

    Chlorination has long been used as an effective and economic biocide for biofouling control in seawater cooling systems. However, the efficacy of chlorine is reduced in the presence of organic content of seawater and the inability of chlorine to effectively penetrate biofilms. Chlorine dioxide is being projected as a possible alternative to chlorine. Experiments were carried out with the help of a seawater circulating facility, in which direct comparison of the efficacy of the two biocides was possible using test condenser tube assemblies. The test condenser tubes made of titanium, SS 316L and Cu-Ni 90/10 were dosed with chlorine and chlorine dioxide. Each dose was evaluated for 30 days. Continuous and intermittent additions of chlorine (0.38 - 0.45 mg L-1 TRO) and chlorine dioxide (0.4 - 0.5 mg L-1) were used, along with control. The flow velocity in the tubes was maintained at 1.5 m/s. Results of the study showed that the efficacy of the biocide to control biofilms depended on the biocide and the material. Continuous chlorination resulted in 75% reduction of viable counts on titanium, followed by 24% reduction on CuNi and 6% reduction on SS 316L surfaces, as compared to the control. When compared to continuous chlorination, increase in bacterial density in the tubes was observed at different regimes of intermittent chlorination. On SS 316L and Cu-Ni surfaces, intermittent chlorination for 1h, once every 3 h, appeared to give adequate protection. Continuous addition of chlorine dioxide resulted in 99% reduction of viable counts on titanium surfaces, followed by 28% reduction on SS 316 L surfaces and 52% reduction on Cu-Ni surfaces, as compared to the controls. The data indicate that the efficacy of biocides to control biofilms depend on not only the biocide and its frequency of application but also the material of construction. (author)

  1. Superconductivity in aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Kubozono, Yoshihiro, E-mail: kubozono@cc.okayama-u.ac.jp [Research Laboratory for Surface Science, Okayama University, Okayama 700-8530 (Japan); Research Center of New Functional Materials for Energy Production, Storage and Transport, Okayama University, Okayama 700-8530 (Japan); Japan Science and Technology Agency, ACT-C, Kawaguchi 332-0012 (Japan); Goto, Hidenori; Jabuchi, Taihei [Research Laboratory for Surface Science, Okayama University, Okayama 700-8530 (Japan); Yokoya, Takayoshi [Research Laboratory for Surface Science, Okayama University, Okayama 700-8530 (Japan); Research Center of New Functional Materials for Energy Production, Storage and Transport, Okayama University, Okayama 700-8530 (Japan); Kambe, Takashi [Department of Physics, Okayama University, Okayama 700-8530 (Japan); Sakai, Yusuke; Izumi, Masanari; Zheng, Lu; Hamao, Shino; Nguyen, Huyen L.T. [Research Laboratory for Surface Science, Okayama University, Okayama 700-8530 (Japan); Sakata, Masafumi; Kagayama, Tomoko; Shimizu, Katsuya [Center of Science and Technology under Extreme Conditions, Osaka University, Osaka 560-8531 (Japan)

    2015-07-15

    Highlights: • Aromatic superconductor is one of core research subjects in superconductivity. Superconductivity is observed in certain metal-doped aromatic hydrocarbons. Some serious problems to be solved exist for future advancement of the research. This article shows the present status of aromatic superconductors. - Abstract: ‘Aromatic hydrocarbon’ implies an organic molecule that satisfies the (4n + 2) π-electron rule and consists of benzene rings. Doping solid aromatic hydrocarbons with metals provides the superconductivity. The first discovery of such superconductivity was made for K-doped picene (K{sub x}picene, five benzene rings). Its superconducting transition temperatures (T{sub c}’s) were 7 and 18 K. Recently, we found a new superconducting K{sub x}picene phase with a T{sub c} as high as 14 K, so we now know that K{sub x}picene possesses multiple superconducting phases. Besides K{sub x}picene, we discovered new superconductors such as Rb{sub x}picene and Ca{sub x}picene. A most serious problem is that the shielding fraction is ⩽15% for K{sub x}picene and Rb{sub x}picene, and it is often ∼1% for other superconductors. Such low shielding fractions have made it difficult to determine the crystal structures of superconducting phases. Nevertheless, many research groups have expended a great deal of effort to make high quality hydrocarbon superconductors in the five years since the discovery of hydrocarbon superconductivity. At the present stage, superconductivity is observed in certain metal-doped aromatic hydrocarbons (picene, phenanthrene and dibenzopentacene), but the shielding fraction remains stubbornly low. The highest priority research area is to prepare aromatic superconductors with a high superconducting volume-fraction. Despite these difficulties, aromatic superconductivity is still a core research target and presents interesting and potentially breakthrough challenges, such as the positive pressure dependence of T{sub c} that is clearly

  2. Revisiting the thermochemistry of chlorine fluorides

    CERN Document Server

    Sánchez, H R

    2016-01-01

    In this work, accurate calculations of standard enthalpies of formation of chlorine fluorides (ClF$_n$, n=1--7; Cl$_2$F and Cl$_3$F$_2$) were performed through the isodesmic reactions scheme. It is argued that, for many chlorine fluorides, the gold standard method of quantum chemistry (CCSD(T)) is not capable to predict enthalpy values nearing chemical accuracy if atomization scheme is used. This is underpinned by a thorough analysis of total atomization energy results and the inspection of multireference features of these compounds. Other thermodynamic quantities were also calculated at different temperatures. In order to complement the energetic description, elimination curves were studied through density functional theory as a computationally affordable alternative to highly correlated wave function-based methods.

  3. Bacterial responses to reactive chlorine species.

    Science.gov (United States)

    Gray, Michael J; Wholey, Wei-Yun; Jakob, Ursula

    2013-01-01

    Hypochlorous acid (HOCl), the active ingredient of household bleach, is the most common disinfectant in medical, industrial, and domestic use and plays an important role in microbial killing in the innate immune system. Given the critical importance of the antimicrobial properties of chlorine to public health, it is surprising how little is known about the ways in which bacteria sense and respond to reactive chlorine species (RCS). Although the literature on bacterial responses to reactive oxygen species (ROS) is enormous, work addressing bacterial responses to RCS has begun only recently. Transcriptomic and proteomic studies now provide new insights into how bacteria mount defenses against this important class of antimicrobial compounds. In this review, we summarize the current knowledge, emphasizing the overlaps between RCS stress responses and other more well-characterized bacterial defense systems, and identify outstanding questions that represent productive avenues for future research. PMID:23768204

  4. Recent Achievements in the Radiation-Catalysed Chlorination of Chlorinated Pentane Derivatives

    International Nuclear Information System (INIS)

    The radiation-catalysed chlorination of the so-called tetrachloro-cyclopentane, the product obtained from cyclopentadiene by addition of chlorine, has already been studied earlier by the authors with success. On maintaining an adequate dosage rate, no ring cleavage occurs, and, mainly for stereochemical reasons, octachloro-cyclopentene forms as an end product - similarly to conventional chlorination carried out at high temperature (400-500oC), but at substantially lower temperature (170oC) and without any resin formation. It is known that besides other end products, octachloro-cyclopentene forms also from perchlorinated pentane, under simultaneous cyclization. In their recent experiments presented here, the authors investigated how and to what extent the yield of octachloro-cyclopentene is affected by additional chlorination of pentane, previously chlorinated under cooling (at 10 to 30oC). The experiments were carried out with a Co60 radiation source of 330 c at a dosage rate of 8 x 103 to 8 x 104r/hr, in a heated reaction mixture, mixed with a chlorine stream for periods not exceeding 30 hr. It was found that also this type of chlorination and cyclization takes place at a temperature substantially lower than the conventional 500-600oC. According to the experiments, in this case it is advisable to raise the initial temperature of 170oC of the reaction gradually to 220oC with the progress of the reaction, in order to promote the cyclization reaction. It was found, namely, that first the paraffin chain was further chlorinated and later the perchlorinated pentane derivatives cyclize partly to octachloro-cyclopentene, under formation of other chlorinated alkane and alkene derivatives. This reaction mechanism was also supported by thermodynamical calculations. The end product contains three main components; its content of octachloro-cyclopentene ranges between 25 and 35%. The data required for the evaluation of the economy of the method will be available only on the

  5. Chlorine diffusion in CdTe

    Energy Technology Data Exchange (ETDEWEB)

    Sadaiyandi, K.; Ramachandran, K. (School of Physics, Madurai Kamaraj Univ. (India))

    1991-06-01

    The experimental results of chlorine diffusion in CdTe reveal that the dominant mechanism for diffusion is through neutral defect pair such as (V{sub Cd}V{sub Te}){sup *}. Here, theoretical calculations are carried out for all the possible mechanisms such as single vacancy, single interstitial, neutral defect pair, and Frenkel defect pair. The results suggest that the most possible mechanism for Cl diffusion in CdTe is that through neutral defect pair, supporting the experiment. (orig.).

  6. Use of pesticides and experience of applying radioisotope techniques in a developing country

    International Nuclear Information System (INIS)

    An evaluation is made of the use of pesticides by Panamanian farmers in a tropical environment, also covering pesticide residues in plant and animal products, man and soil. In addition, experience with radioisotope techniques is described. Chemical control is common practice among farmers. Each year, 5000 to 6000 t of pesticides are used, especially in horticulture and banana cultivation. Herbicides and insecticides predominate in terms of quantity, and fungicides in terms of frequency of application. Use of the so-called persistent organo-chlorines over the last few decades has led to the presence of residues in plant and animal products in amounts less than 2.2 and 0.1 mg/kg for DDT and lindane, respectively. An average of 11 mg of DDT per kilogram of fat has been detected in the population; about 50% of the persons handling agrochemicals showed direct exposure. Taking into account local practices and tropical conditions, an evaluation is being made of widely used pesticides (maneb, paraquat and 2,4-D) labelled with 14C. The studies have yielded additional information on the behaviour and the residues of these important additives in the environment and in fruits. (author). 3 refs, 1 fig., 5 tabs

  7. Short Assessment Survey of Organochlorine Pesticides in Marine Environment of Damb (Sonmiani Balochistan

    Directory of Open Access Journals (Sweden)

    M. Saleem

    2013-09-01

    Full Text Available To assess the contamination levels of organochlorine pesticides (OCPs fifteen type (alpha, beta, gamma and delta HCH, Heptachlor, Heptachlor-epoxide, Endosulfan-I, Endosulfan-II, Aldrin, Dieldrin, Endrin, Endrin aldehyde, 4-4΄ DDT, 4,4΄ DDE and 4,4΄ DDD of OCPS in samples of sea water, sediments, four fish and two crab species were determined in Damb (Sonmiani coastal area. DDT, HCH and its metabolites found most dominating while Endrin, Dieldrin and Heptachlor recorded higher among the fifteen monitored pesticides in Damb (Sonmiani coastal water. All these pesticides are found below the chronic concentration levels as set by the Coastal Water Quality Criteria for Washington State. HCH and Heptachlor were observed to be highest in the coastal sediments of Damb (Sonmiani coastal area and these values are higher than the Canadian Interim Sediment Quality Standard. DDT, Endosulfan, its metabolites and isomers detected high concentration in marine biota, while α-BHC, Heptachlor and Endrin were also detected in low concentration. A preliminary risk assessment indicates that the daily intake of chlorinated pesticides by people consuming fish from the Damb (Sonmiani coastal area is still very low and, therefore, is not likely to cause an immediate risk.

  8. Chlorination and Carbochlorination of Cerium Oxide

    International Nuclear Information System (INIS)

    The chlorination and carbochlorination of cerium oxide were studied by thermogravimetry under controlled atmosphere (TG) in the 7000C 9500C temperature range.Both reactants and products were analyzed by X-ray diffraction (RX), scanning electronic microscopy (SEM) and energy dispersive spectroscopy (EDS). Thermodynamic calculations were performed by computer assisted software.The chlorination starts at a temperature close to 8000C.This reaction involves the simultaneous formation and evaporation of CeCl3.Both processes control the reaction rate and their kinetic may not be easily separated.The apparent chlorination activation energy in the 8500C-9500C temperature range is 172 to 5 kJ/ mole.Carbon transforms the CeO2-Cl2 into a more reactive system: CeO2-C-Cl2, where the effects of the carbon content, total flow rate and temperature were analyzed.The carbochlorination starting temperature is 7000C.This reaction is completed in one step controlled by mass transfer with an apparent activation energy of 56 to 5 kJ/mole in the 8500C-9500C temperature range

  9. Direct hydrocarbon fuel cells

    Science.gov (United States)

    Barnett, Scott A.; Lai, Tammy; Liu, Jiang

    2010-05-04

    The direct electrochemical oxidation of hydrocarbons in solid oxide fuel cells, to generate greater power densities at lower temperatures without carbon deposition. The performance obtained is comparable to that of fuel cells used for hydrogen, and is achieved by using novel anode composites at low operating temperatures. Such solid oxide fuel cells, regardless of fuel source or operation, can be configured advantageously using the structural geometries of this invention.

  10. Biogeochemistry of Halogenated Hydrocarbons

    Science.gov (United States)

    Adriaens, P.; Gruden, C.; McCormick, M. L.

    2003-12-01

    Halogenated hydrocarbons originate from both natural and industrial sources. Whereas direct anthropogenic emissions to the atmosphere and biosphere are often easy to assess, particularly when they are tied to major industrial activities, the attribution of emissions to other human activities (e.g., biomass burning), diffuse sources (e.g., atmospheric discharge, run off), and natural production (e.g., soils, fungi, algae, microorganisms) are difficult to quantify. The widespread occurrence of both alkyl and aryl halides in groundwater, surface water, soils, and various trophic food chains, even those not affected by known point sources, suggests a substantial biogeochemical cycling of these compounds (Wania and Mackay, 1996; Adriaens et al., 1999; Gruden et al., 2003). The transport and reactive fate mechanisms controlling their reactivity are compounded by the differences in sources of alkyl-, aryl-, and complex organic halides, and the largely unknown impact of biogenic processes, such as enzymatically mediated halogenation of organic matter, fungal production of halogenated hydrocarbons, and microbial or abiotic transformation reactions (e.g., Asplund and Grimvall, 1991; Gribble, 1996; Watling and Harper, 1998; Oberg, 2002). The largest source may be the natural halogenation processes in the terrestrial environment, as the quantities detected often exceed the amount that can be explained by human activities in the surrounding areas ( Oberg, 1998). Since biogeochemical processes result in the distribution of a wide range of halogenated hydrocarbon profiles, altered chemical structures, and isomer distributions in natural systems, source apportionment (or environmental forensics) can often only be resolved using multivariate statistical methods (e.g., Goovaerts, 1998; Barabas et al., 2003; Murphy and Morrison, 2002).This chapter will describe the widespread occurrence of halogenated hydrocarbons, interpret their distribution and biogeochemical cycling in light of

  11. Formation of chlorinated organic compounds in fluidized bed combustion of recycled fuels; Kloorattujen orgaanisten yhdisteiden muodostuminen kierraetyspolttoaineiden leijukerrospoltossa

    Energy Technology Data Exchange (ETDEWEB)

    Vesterinen, R.; Kallio, M.; Kirjalainen, T.; Kolsi, A.; Merta, M. [VTT Energy, Jyvaeskylae (Finland)

    1997-10-01

    Four tests of co-combustion of recycled fuels (REP) with peat and coal in the 15 kW fluidized bed reactor were performed. The recycled fuel was so-called dry fraction in four vessels sampling at Keltinmaeki. In three tests a part of peat energy was replaced with coal. The mixtures were prepared so that in all mixtures 25 % of energy was recycled fuel and 75 % was either peat or the mixture of peat and coal. The concentrations of polyaromatic hydrocarbons (PAH), polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) and chlorophenols decreased with increasing part of coal due to the increasing sulphur/chlorine ratio. Principal Component Analysis (PCA) and Partial Least Square regression analysis (PLS) showed that the chlorine, copper and sulphur contents of the fuel effected most on the concentrations of chlorophenols, chlorobenzenes, PCBs and PCDDs/PCDFs. Other variables influencing on a model were the lead concentration and the sulphur/chlorine ratio in fuel and the hydrogen chloride concentration of the flue gas. The concentrations of chlorophenols and chlorobenzenes were also significant for PCDD/PCDF concentrations in flue gas. The sulphur, chlorine, copper and chromium contents in fly ash and the temperature of the reactor influenced on the chlorophenol, chlorobenzene, PCB and PCDD/PCDF concentrations in fly ash. The chlorophenol and chlorobenzene contents in fly ash, the sulphur/chlorine ratio and the lead content in fuel, the sulphur dioxide, hydrogen chloride and carbon monoxide concentrations in flue gas had also influence on PCDD/PCDF concentrations in fly ash

  12. THERMOCHEMISTRY OF HYDROCARBON RADICALS

    Energy Technology Data Exchange (ETDEWEB)

    Kent M. Ervin, Principal Investigator

    2004-08-17

    Gas phase negative ion chemistry methods are employed to determine enthalpies of formation of hydrocarbon radicals that are important in combustion processes and to investigate the dynamics of ion-molecule reactions. Using guided ion beam tandem mass spectrometry, we measure collisional threshold energies of endoergic proton transfer and hydrogen atom transfer reactions of hydrocarbon molecules with negative reagent ions. The measured reaction threshold energies for proton transfer yield the relative gas phase acidities. In an alternative methodology, competitive collision-induced dissociation of proton-bound ion-molecule complexes provides accurate gas phase acidities relative to a reference acid. Combined with the electron affinity of the R {center_dot} radical, the gas phase acidity yields the RH bond dissociation energy of the corresponding neutral molecule, or equivalently the enthalpy of formation of the R{center_dot} organic radical, using equation: D(R-H) = {Delta}{sub acid}H(RH) + EA(R) - IE(H). The threshold energy for hydrogen abstraction from a hydrocarbon molecule yields its hydrogen atom affinity relative to the reagent anion, providing the RH bond dissociation energy directly. Electronic structure calculations are used to evaluate the possibility of potential energy barriers or dynamical constrictions along the reaction path, and as input for RRKM and phase space theory calculations. In newer experiments, we have measured the product velocity distributions to obtain additional information on the energetics and dynamics of the reactions.

  13. 40 CFR 158.2010 - Biochemical pesticides data requirements.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Biochemical pesticides data...) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2010 Biochemical pesticides... required to support registration of biochemical pesticides. Sections 158.2080 through 158.2084 identify...

  14. 40 CFR 158.2110 - Microbial pesticides data requirements.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Microbial pesticides data requirements...) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2110 Microbial pesticides data requirements. (a) For all microbial pesticides. (1) The following § 158.2120 through §...

  15. 40 CFR 152.175 - Pesticides classified for restricted use.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Pesticides classified for restricted...) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES Classification of Pesticides § 152.175 Pesticides classified for restricted use. The following uses of pesticide products containing...

  16. 40 CFR 158.2000 - Biochemical pesticides definition and applicability.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Biochemical pesticides definition and...) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2000 Biochemical pesticides definition and applicability. This subpart applies to all biochemical pesticides as defined in paragraphs...

  17. Organochlorine Pesticides in the Environment

    Science.gov (United States)

    Stickel, L.F.

    1968-01-01

    Each year for nearly 20 years, thousands of pounds of persistent organochlorine pesticides have been applied to outdoor areas in many countries. These compounds may last for a very long time in the environment, and be carried by wind, water, and animals to places far distant from where they are used. As a result, most living organisms now contain organochlorine residues. This paper constitutes a selective review of the literature concerning the occurrence, distribution, and effects of organochlorines in the environment. Highest concentrations generally occur in carnivorous species. Thus predatory and fish-eating birds ordinarily have higher residues than do herbivores; quantities are similar in birds of similar habits in different countries. Any segment of the ecosystem - marshland, pond, forest, or field - receives various amounts and kinds of pesticides at irregular intervals. The different animals absorb, detoxify, store, and excrete pesticides at different rates. Different degrees of magnification of pesticide residues by living organisms in an environment are the practical result of many interactions that are far more complex than implied by the statement of magnification up the food chain. These magnifications may be millions of times from water to mud or only a few times from food to first consumer. Direct mortality of wild animals as an aftermath of recommended pesticide treatments has been recorded in the literature of numerous countries. However, accidents and carelessness also accompany pesticide use on a percentage basis and are a part of the problem. More subtle effects on the size and species composition of populations are more difficult to perceive in time to effect remedies. The possibility of ecological effects being mediated through changes in physiology and behavior has received some attention and has resulted in some disquieting findings. These include discovery of the activity of organochlorines in stimulating the breakdown of hormones or in

  18. 77 FR 23713 - Pesticides; Final Guidance on Material Safety Data Sheets as Pesticide Labeling; Request for...

    Science.gov (United States)

    2012-04-20

    ... relationship between EPA-approved labels for pesticides registered under the Federal Insecticide, Fungicide... AGENCY Pesticides; Final Guidance on Material Safety Data Sheets as Pesticide Labeling; Request for.... SUMMARY: The Agency is announcing the availability of a Pesticide Registration Notice (PR Notice)...

  19. Attacks of Asthma due to Chlorinized Water: Case Report

    Directory of Open Access Journals (Sweden)

    Murat Eyup Berdan

    2008-02-01

    Full Text Available The presence of a high prevalence of bronchial hyperresponsiveness and asthma-like symptoms in swimmers has been reported. But, attacks of asthma which is related to chlorinized water is rare. Chlorine, a strong oxidizing agent, is an important toxic gas that the swimmer can breath during swimming and a worker can exposed to chlorine while he or she was using water with chlorine at home. We describe a persistent increase in nonspecific bronchial hyperresponsiveness following chronic exposure to strong respiratory irritant with chlorinized water in two subjects with no past history of asthma or atopy. We conclude that airway hyperresponsiveness can develop or increase after chronic inhalation of high concentrations of irritants such as chlorinized water an indoor irritant factor and that these changes may be prolonged. [TAF Prev Med Bull. 2008; 7(1: 87-90

  20. Attacks of Asthma due to Chlorinized Water: Case Report

    Directory of Open Access Journals (Sweden)

    Murat Eyup Berdan

    2008-02-01

    Full Text Available The presence of a high prevalence of bronchial hyperresponsiveness and asthma-like symptoms in swimmers has been reported. But, attacks of asthma which is related to chlorinized water is rare. Chlorine, a strong oxidizing agent, is an important toxic gas that the swimmer can breath during swimming and a worker can exposed to chlorine while he or she was using water with chlorine at home. We describe a persistent increase in nonspecific bronchial hyperresponsiveness following chronic exposure to strong respiratory irritant with chlorinized water in two subjects with no past history of asthma or atopy. We conclude that airway hyperresponsiveness can develop or increase after chronic inhalation of high concentrations of irritants such as chlorinized water an indoor irritant factor and that these changes may be prolonged. [TAF Prev Med Bull 2008; 7(1.000: 87-90

  1. Kinetic modelling of chlorination of nitrided ilmenite using MATLAB

    Science.gov (United States)

    Ramakrishnan, Sivakumar; Kwok, Teong Chen; Hamid, Sheikh Abdul Rezan Sheikh Abdul

    2016-07-01

    In the present study, chlorination of nitride ilmenite using 2k factorial design was investigated. The reduction experiments were carried out in a temperature range of 400°C to 500°C, chlorination duration from 1 hour to 3 hours and using different type of carbon reactant. Phases of raw materials and reduced samples were analyzed by X-ray diffraction (XRD). Ilmenite was reduced to TiOxCyNz through carbothermal and nitridation for further chlorination into titanium tetrachloride. The Design of Experiment analysis suggested that the types of carbon reactant contribute most influence to the extent of chlorination of nitride ilmenite. The extent of chlorination was highest at 500°C with 3 hours chlorination time and carbon nanotube as carbon reactant.

  2. Pesticides Linked to Raised Risk of ALS

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_158737.html Pesticides Linked to Raised Risk of ALS One toxin ... MONDAY, May 9, 2016 (HealthDay News) -- Exposure to pesticides and other chemicals may increase the risk for ...

  3. Pesticide risks around the home (image)

    Science.gov (United States)

    Pesticides are substances which kill or deter unwanted pests, such as insects or rodents. These substances can ... avoid an accidental ingestion is to keep all pesticides out of the reach of children.

  4. 76 FR 10026 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2011-02-23

    ... AGENCY Pesticide Products; Registration Applications AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: This notice announces receipt of applications to register new uses for pesticide... the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), as amended. EPA is publishing...

  5. Neurobehavioral and neurodevelopmental effects of pesticide exposures

    DEFF Research Database (Denmark)

    London, Leslie; Beseler, Cheryl; Bouchard, Maryse F;

    2012-01-01

    The association between pesticide exposure and neurobehavioral and neurodevelopmental effects is an area of increasing concern. This symposium brought together participants to explore the neurotoxic effects of pesticides across the lifespan. Endpoints examined included neurobehavioral, affective ...

  6. Pesticides Linked to Raised Risk of ALS

    Science.gov (United States)

    ... nlm.nih.gov/medlineplus/news/fullstory_158737.html Pesticides Linked to Raised Risk of ALS One toxin ... MONDAY, May 9, 2016 (HealthDay News) -- Exposure to pesticides and other chemicals may increase the risk for ...

  7. 75 FR 5077 - Pesticide Product; Registration Application

    Science.gov (United States)

    2010-02-01

    ... Pollution Prevention Division (7511P), Office of Pesticide Programs, Environmental Protection Agency, 1200... the FDA as a stabilizer in polymers used in producing, manufacturing, packaging, processing, and... Pollution Prevention Division, Office of Pesticide Programs. BILLING CODE 6560-50-S...

  8. Treatment of algae-induced tastes and odors by chlorine, chlorine dioxide and permanganate

    OpenAIRE

    Buffin, Lisa Webster

    1992-01-01

    Chlorine (C12(sq»' chlorine dioxide (Cl02 ) and potassium permanganate (KMn04) were evaluated as oxidants for the removal of grassy and cucumber odors associated with the pure compounds, cis-3-hexenol and trans-2, cis-6-nonadienal, respectively, and for the removal of fishy odors associated with a culture of an alga, Synura petersenii. The effects of the oxidants on the pure compounds were assessed both by Flavor Profile Analysis (FPA) and gas chromatography/mass spectrometry (GC/MS). The ef...

  9. Cyclopalladated Ferrocenylimine Catalyzed Chlorination of 2-Arylbenzoxazoles%Cyclopalladated Ferrocenylimine Catalyzed Chlorination of 2-Arylbenzoxazoles

    Institute of Scientific and Technical Information of China (English)

    冷瑜婷; 杨帆; 吴养洁; 李克

    2011-01-01

    An efficient and facile protocol for palladacycle-catalyzed chlorination of 2-arylbenzoxazoles was developed. The results represent the first examples involving the palladacycle as the catalyst for such chlorination. This chlori- nation was not a ligand-directed ortho-C--H activation, but an electrophilic substitution process at the para-position of the nitrogen atom in the benzo ring of benzoxazole moiety, the regiochemistry of which had been confirmed by HMBC spectral analysis. The catalytic system could tolerate various halogen atoms, such as F, Cl and Br, affording the corresponding products in moderate to excellent yields.

  10. The removal of phenols from oily wastewater by chlorine dioxide

    OpenAIRE

    Hsu, Chung-Jung

    1988-01-01

    Treatability studies were performed on oily wastewaters produced by petroleum and canning industries. Chlorine dioxide was used for the removal of phenolic compounds from these oily wastewaters. Most of phenolic compounds can be destroyed by chlorine dioxide within 15 minutes if CI02-to-phenol ratios of higher than 5.0 are provided. Factors such as pH, temperature, and COD have little effect on phenol removal. The effectiveness of chlorine dioxide treatment depends critic...

  11. Blends of caprolactam/caprolactone copolymers and chlorinated polymers

    OpenAIRE

    Alberda van Ekenstein, G.O.R.; Deuring, H.; ten Brinke, G.; Ellis, T. S.

    1997-01-01

    The phase behaviour of blends of chlorinated polyethylene, polyvinyl chloride (PVC) and chlorinated PVC with random copolymers of caprolactone and caprolactam has been investigated and the results correlated with a binary interaction model. The known miscibility of polycaprolactone in the chlorinated polymers is not compromised until a relatively high lactam content in the copolymer is attained. The incorporation of segmental interaction parameters, derived from separate studies involving pol...

  12. Degradation of Chlorinated Aliphatic Hydrocarbons by Methylosinus trichosporium OB3b Expressing Soluble Methane Monooxygenase

    NARCIS (Netherlands)

    Oldenhuis, Roelof; Vink, Ruud L.J.M.; Janssen, Dick B.; Witholt, Bernard

    1989-01-01

    Degradation of trichloroethylene (TCE) by the methanotrophic bacterium Methylosinus trichosporium OB3b was studied by using cells grown in continuous culture. TCE degradation was a strictly cometabolic process, requiring the presence of a cosubstrate, preferably formate, and oxygen. M. trichosporium

  13. [Removal of Waste Gas Containing Mixed Chlorinated Hydrocarbons by the Biotrickling Filter].

    Science.gov (United States)

    Chen, Dong-zhi; Miao, Xiao-ping; Ouyang, Du-juan; Ye, Jie-xu; Chen, Jian-meng

    2015-09-01

    An experimental investigation on purification of waste gas contaminated with a mixture of dichloromethane (DCM) and dichloroethane(1,2-DCA) was conducted in a biotrickling filter (BTF) inoculated with activated sludge of pharmaceuticals industry. Stable removal efficiency(RE) above 80% for DCM and above 75% for 1,2-DCA were achieved after 35 days, indicating that biofilm was developed. The best elimination capacity (EC) of DCM and 1,2-DCA were 13 g.(m3.h)-1 and 10 g.(m3.h)-1 respectively. And there was a linear relationship between the production of CO2 and mixed gas EC, the maximum mineralization rate of mixed gas stabled at 61. 2%. The interaction test indicated that DCM and 1,2-DCA would inhibit with each other. The changing of biomass of BTF during the operation process was also been studied. PMID:26717675

  14. Session 6: Catalytic Dechlorination Reaction of Chlorinated Hydrocarbons with Water Using nano-structured Alumina

    Energy Technology Data Exchange (ETDEWEB)

    Abbas, Khaleel [United Arab Emirates Univ., Dept. of Chemistry, Al-Ain (United States)

    2004-07-01

    Herein, we report our recent results from a study on the catalytic dechlorination reactions of 1,2-dichloroethane (DCE) and carbon tetrachloride (CTC) with water using HSA-Al{sub 2}O{sub 3} as the catalyst. The obtained experimental results are explained. (O.M.)

  15. Temperature Dependence of the Inhibition of Positronium by Chlorine- Substituted Hydrocarbons in Non-Polar Liquids

    DEFF Research Database (Denmark)

    Wikander, G.; Mogensen, O.E.; Pedersen, Niels Jørgen

    1984-01-01

    Positron annihilation lifetime spectra were measured for solutions of 1,2,3,5-C6H2Cl4 in hexane, toluene, m-xylene and mesitylene, CCl4 in hexane and toluene, and C2HCl3 in n-hexane for concentrations below 1 M and at various temperatures between −30°C and 67°C. The Ps inhibition by C6H2Cl4 was...... roughly 14 times stronger at −30°C than at 67°C in toluene, m-xylene, and mesitylene, while that of CCl4 displayed hardly any temperature dependence in hexane and toluene. Previously, the Ps inhibition by C6H2Cl4 in various liquids at 20°C was explained by a competition between electron pick off by the...

  16. Application of BGPR tomography investigate the Soil and Groundwater Contaminated with Chlorinated Hydrocarbon:Case study

    Science.gov (United States)

    Liu, H. C.; Lin, C. P.; Dong, T. H.; Yang, C. H.

    2014-12-01

    The success of an environmental contaminated project is often determined by the extent to which it is able to ascertain and control subsurface conditions. At present, site managers have limited tools to gain detailed information on the distribution of possible underground barriers or anomalous bodies. The technology employed in Taiwan to evaluate or confirm subsurface anomalies relies primarily on surface geophysical surveys, borehole drillings, or past records. Surface ground-penetrating radar GPR survey is among the most popular of these methods. Surface GPR technique can be used in many ways, but this method is not always the best suited to Taiwan's conditions. Surface GPR surveys are adversely affected by the conductivity of silty/clayey sediment and cultural noises. As a result, when surface GPR surveys are used, both detection and resolution of subsurface anomalies will decrease with depth. In order to overcome these obstacles, the use of borehole GPR BGPR with a few boreholes may provide a more direct and effective way to detect an underground target. Recent improvement in the quality of BGPR contributes to the suitability of this type of survey work when implemented on construction sites. This paper ues the BGPR geophysical technology has been developed to overcome above limitations. The information of multi-wells logging could be used to interpret the permeability of subsurface, the dominate flow path and the hot-spot for evaluating the distribution of pollution and the efficiency of remediation in different time sequences.

  17. ANAEROBIC BIOTRANSFORRNATION OF CHLORINATED ALIPHATIC HYDROCARBONS: UGLY DUCKLING TO BEAUTIFUL SWAN. (R825549C044)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  18. ANAEROBIC BIOTRANSFORMATION OF CHLORINATED ALIPHATIC HYDROCARBONS: UGLY DUCKLING TO BEAUTIFUL SWAN. (R825549C053)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  19. Biodegradation of chlorinated and unsaturated hydrocarbons in relation to biological waste-gas treatment.

    NARCIS (Netherlands)

    Hartmans, S.

    1993-01-01

    The original goal of the research described in this thesis was to develop a biological process for the removal of vinyl chloride from waste gases. The gaseous and carcinogenic vinyl chloride is used to produce the plastic polyvinyl chloride (PVC). During this production process waste gases containin

  20. Quantification of temperature impacts on the dissolution of chlorinated hydrocarbons into groundwater

    Science.gov (United States)

    Koproch, Nicolas; Popp, Steffi; Köber, Ralf; Beyer, Christof; Bauer, Sebastian; Dahmke, Andreas

    2016-04-01

    Shallow thermal energy storage has great potential for heat storage especially in urban and industrial areas. However, frequently existing organic groundwater contaminations in such areas were currently seen as exclusion criteria for thermal use of the shallow subsurface, since increased contaminant discharge is feared as consequence of heating. Contaminant discharge is influenced by a complex interaction of processes and boundary conditions as e.g. solubility, dispersion, viscosity and degradation, where there is still a lack of experimental evidence of the temperature dependent interaction. Even existing studies on basic influencing factors as e.g. temperature dependent solubilities show contradictory results. Such knowledge gaps should be reduced to improve the basis and liability of numerical model simulations and the knowledge base to enable a more differentiated and optimized use of resources. For this purpose batch as well as 1- and 2-dimensional experimental studies concerning the temperature dependent release of TCE (trichloroethylene) from a NAPL (non aqueous phase liquid) source are presented and discussed. In addition, this experimental studies are accompanied by a numerical model verification, where extensions of existing numerical model approaches on basis of this obtained experimental results are developed. Firstly, temperature dependent TCE solubility data were collected using batch experiments with significantly better temperature resolution compared to earlier studies, showing a distinct minimum at 35°C and increased solubility towards 5°C and 70°C. Secondly, heated 1-dimensional stainless steel columns homogenously filled with quartz sand were used to quantify source zone depletion and contaminant discharge at 10-70°C. Cumulative mass discharge curves indicated two blob categories with distinct differences in dissolution kinetics. Increasing the temperature showed here an increase of the amount of fast dissolving blobs indicating higher NAPL-water contact areas. Thirdly, heatable 2D-tanks (40 cm x 25 cm x 10 cm) homogenously filled with quartz sand and percolated by distilled H2O were used to investigate the dissolution behavior and plume development of TCE from a residual source zone (5 cm x 5 cm x 10 cm) at 10-70°C. Using NAPL source zone saturation of 5% (Case A) and 20% (Case B) two exemplary cases of a depleted and a fresh source zone were investigated. TCE outflow concentrations in case A increased continuously with increasing temperature, but were controlled by the temperature-dependent solubility in Case B. The experimental results showed that the TCE mass transfer rate has a minimum at about 40°C, if dissolution is non-rate limited and a continuous increase with increasing temperature for rate-limited systems. Implementation of temperature dependent NAPL dissolution and two different blob categories with different mass transfer rate coefficients in the OpenGeoSys code proved successful in reproducing the experimental results. Acknowledgments: The presented work is part of the ANGUS+ project (03EK3022) funded by the German Ministry of Education and Research (BMBF).

  1. UNWANTED AGRICULTURAL PESTICIDES: STATE DISPOSAL SYSTEMS

    OpenAIRE

    Centner, Terence J.

    1997-01-01

    Millions of pounds of unwanted pesticides have accumulated in barns throughout our country. The potential environmental and health risks posed by this situation has garnered public attention and governmental action. The federal government has revised its Universal Waste Rule so that it is easier to dispose of unwanted pesticides rather than simply banned pesticides. Nearly every state has initiated efforts to collect and dispose of accumulated pesticides in a safe manner. While the possession...

  2. Mechanisms of inactivation of poliovirus by chlorine dioxide and iodine.

    OpenAIRE

    Alvarez, M E; O'Brien, R T

    1982-01-01

    Chlorine dioxide and iodine inactivated poliovirus more efficiently at pH 10.0 than at pH 6.0. Sedimentation analyses of viruses inactivated by chlorine dioxide and iodine at pH 10.9 showed that viral RNA separated from the capsids, resulting in the conversion of virions from 156S structures to 80S particles. The RNAs release from both chlorine dioxide- and iodine-inactivated viruses cosedimented with intact 35S viral RNA. Both chlorine dioxide and iodine reacted with the capsid proteins of p...

  3. Pesticides: Food and environmental implications

    International Nuclear Information System (INIS)

    Pesticides are an integral part of modern agriculture, also in most developing countries. Although the annual average consumption of active ingredients in agriculture may be below 0.1 kg a.i./ha, most countries now consume more than 2 kg a.i./ha; some of the intensively cropped regions in South-East Asia are exposed to even higher amounts. Inherent contamination of the environment follows if rules and regulations are not strictly adhered to. The search for safer, less persistent and more specific pesticides and examination of the fate of applied pesticides in various regions of the world were the main themes of the symposium. Special emphasis was placed on the use of nuclear techniques, especially on labelled compounds in research. The Proceedings include all the papers and posters that were presented. Refs, figs and tabs

  4. 75 FR 76463 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2010-12-08

    ... AGENCY Pesticide Products; Registration Applications AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: This notice announces receipt of applications to register new uses for pesticide....regulations.gov . Follow the on-line instructions for submitting comments. Mail: Office of Pesticide...

  5. Pesticide use in Vietnamese vegetable production

    NARCIS (Netherlands)

    Hoi, P.V.; Mol, A.P.J.; Oosterveer, Peter; Brink, van den P.J.; Huong, P.T.M.

    2016-01-01

    Vietnam has had varying success over the past decade with its pesticides policy. Some of the most toxic pesticides have been banned from the market. But while many countries have successfully decreased agricultural pesticide use per hectare, this has not (yet) happened in Vietnam. Due to insuffic

  6. Pesticides in Schools: Reducing the Risks.

    Science.gov (United States)

    New York State Office of the Attorney General, Albany.

    This report presents findings of state-wide use of pesticides in New York public schools along with a description of the survey, information about the potential dangers of these chemicals, and the steps schools and communities can take to minimize pesticide use. Findings show that 87 percent of New York's schools use pesticides that contain…

  7. 75 FR 24695 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2010-05-05

    ... AGENCY Pesticide Products; Registration Applications AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: This notice announces receipt of applications to register new uses for pesticide....regulations.gov . Follow the on-line instructions for submitting comments. Mail: Office of Pesticide...

  8. Chlorinated and nitrogenous disinfection by-product formation from ozonation and post-chlorination of natural organic matter surrogates.

    Science.gov (United States)

    Bond, Tom; Templeton, Michael R; Rifai, Omar; Ali, Hussain; Graham, Nigel J D

    2014-09-01

    Ozonation before chlorination is associated with enhanced formation of chloropicrin, a halonitromethane disinfection by-product (DBP), during drinking water treatment. In order to elucidate reasons for this, five natural organic matter (NOM) surrogates were treated using both chlorination and ozonation-chlorination under controlled laboratory conditions. Selected surrogates comprised two phenolic compounds, two free amino acids and one dipeptide; these were resorcinol, 3-aminophenol, L-aspartic acid, β-alanine and ala-ala, respectively. Quantified DBPs included chloropicrin, chloroform, dichloroacetonitrile and trichloroacetonitrile. Relative to chlorination alone, increases in the formation of chloropicrin from ozonation-chlorination varied from 138% for 3-aminophenol to 3740% for ala-ala for the four amine surrogates. This indicates that ozone is more effective than chlorine in mediating a rate-limiting oxidation step in chloropicrin formation, most plausibly involving conversion of an amine group to a nitro group. While both hydrophilic and hydrophobic surrogates acted as chloropicrin precursors, ala-ala was the most reactive precursor following ozonation-chlorination. Since peptides are far commoner in drinking water sources than free amino acids, further research into chemical oxidation of these species by ozone and chlorine is recommended. In contrast, oxidation with ozone prior to chlorination reduced chloroform formation moderately for the two phenolic compounds.

  9. Scenarios Evaluation Tool for Chlorinated Solvent MNA

    Energy Technology Data Exchange (ETDEWEB)

    Vangelas, Karen; Michael J. Truex; Charles J. Newell; Brian Looney

    2007-02-28

    Over the past three decades, much progress has been made in the remediation of chlorinated solvents from the subsurface. Yet these pervasive contaminants continue to present a significant challenge to the U.S. Department of Energy (DOE), other federal agencies, and other public and private organizations. The physical and chemical properties of chlorinated solvents make it difficult to rapidly reach the low concentrations typically set as regulatory limits. These technical challenges often result in high costs and long remediation time frames. In 2003, the DOE through the Office of Environmental Management funded a science-based technical project that uses the U.S. Environmental Protection Agency's technical protocol (EPA, 1998) and directives (EPA, 1999) on Monitored Natural Attenuation (MNA) as the foundation on which to introduce supporting concepts and new scientific developments that will support remediation of chlorinated solvents based on natural attenuation processes. This project supports the direction in which many site owners want to move to complete the remediation of their site(s), that being to complete the active treatment portion of the remedial effort and transition into MNA. The overarching objective of the effort was to examine environmental remedies that are based on natural processes--remedies such as Monitored Natural Attenuation (MNA) or Enhanced Attenuation (EA). The research program did identify several specific opportunities for advances based on: (1) mass balance as the central framework for attenuation based remedies, (2) scientific advancements and achievements during the past ten years, (3) regulatory and policy development and real-world experience using MNA, and (4) exploration of various ideas for integrating attenuation remedies into a systematic set of ''combined remedies'' for contaminated sites. These opportunities are summarized herein and are addressed in more detail in referenced project documents and

  10. Thermal degradation of sucralose: a combination of analytical methods to determine stability and chlorinated byproducts

    Science.gov (United States)

    de Oliveira, Diogo N.; de Menezes, Maico; Catharino, Rodrigo R.

    2015-04-01

    In the late years, much attention has been brought to the scientific community regarding the safety of sucralose and its industrial applications. Although it is the most used artificial sweetener in foods and pharmaceuticals, many questions still arise on its potential to form chlorinated byproducts in high temperatures, as demonstrated by several recent studies. In the present contribution, we use a combination of differential scanning calorimetry and thermogravimetric analysis coupled with infrared spectroscopy (DSC/TGA/IR), Hot-stage microscopy (HSM) and high-resolution mass spectrometry (HRMS) on samples submitted to water bath at mild temperatures to evaluate a broad spectrum of hazardous compounds formed in the degradation of this product. TGA/IR has revealed that there is effective decomposition in form of CO2 along with the formation of hydrogen chloride and other minor compounds. HSM results have provided accurate information, where the melting of the crystals was observed, followed by decomposition. Chlorinated derivatives, including polychlorinated aromatic hydrocarbons (PCAHs) were also confirmed by HRMS. These findings not only corroborate the suspected instability of sucralose to high temperatures, but also indicate that even exposed to mild conditions the formation of hazardous polychlorinated compounds is observed.

  11. Chlorination byproducts in drinking water produced from thermal desalination in United Arab Emirates.

    Science.gov (United States)

    Elshorbagy, Walid; Abdulkarim, Mohamed

    2006-12-01

    Oil activities in the Arabian Gulf can potentially affect the quality of the intake water available for coastal desalination plants. This paper addresses such situation by investigating the quality of intake water and desalinated water produced by a desalination plant located near a coastal industrial complex in United Arab Emirates (UAE). Analyses of the organic compounds on the intake seawater reported non-detected levels in most samples for the three tested organic groups; namely Polyaromatic Hydrocarbons (PAHs), Phenols, and Polychlorinated Biphenyls (PCBs). Trihalomethanes (THMs) and Haloacetic Acids (HAAs) were also tracked in the intake sea water, throughout the desalination processes, and in the final produced drinking water, to evaluate the undertaken pre- and post chlorination practices. The levels of considered Chlorination Byproducts (CBPs) were mostly found below the permissible international limits with few exceptions showing tangible levels of bromoform in the intake seawater and in the final produced drinking water as well. Lab-controlled experiments on the final produced distillate showed little contribution of its blending with small percentage of seawater upon the formation of trihalomethane and in particular, bromoform. Such results indicate that the organic precursors originated in the seawater are responsible for bromoform formation in the final distillate. PMID:16738754

  12. Pesticide mass budget in a stormwater wetland.

    Science.gov (United States)

    Maillard, Elodie; Imfeld, Gwenaël

    2014-01-01

    Wetlands are reactive landscape zones that provide ecosystem services, including the improvement of water quality. Field studies distinguishing pesticide degradation from retention to evaluate the sink and source functions of wetlands are scarce. This study evaluated based on a complete mass budget the partitioning, retention, and degradation of 12 pesticides in water, suspended solids, sediments, and organisms in a wetland receiving contaminated runoff. The mass budget showed the following: (i) dissolved pesticides accounted for 95% of the total load entering the wetland and the pesticide partitioning between the dissolved phase and the suspended solids varied according to the molecules, (ii) pesticides accumulated primarily in the dithiocarbamates were degraded under oxic conditions in spring, whereas glyphosate and aminomethylphosphonic acid (AMPA) degradation occurred under reducing conditions during the summer. The complete pesticide mass budget indicates the versatility of the pesticide sink and source functions of wetland systems. PMID:25003558

  13. Pesticides, People, and the Environment

    Science.gov (United States)

    Miller, Roxanne Greitz

    2005-01-01

    If a teacher were to ask his/her students what they do when they find ants or other insects in their homes, their most common response would probably be, "Get the bug spray!" Because students are not only being exposed to pesticides but are also developing patterns of behavior likely to continue throughout their lives. Discussions about…

  14. Chiral Synthons in Pesticide Syntheses

    NARCIS (Netherlands)

    Feringa, Bernard

    1988-01-01

    The use of chiral synthons in the preparation of enantiomerically pure pesticides is described in this chapter. Several routes to chiral synthons based on asymmetric synthesis or on natural products are illustrated. Important sources of chiral building blocks are reviewed. Furthermore the implicatio

  15. Simulating pesticide transport in urbanized catchments: a new spatially-distributed dynamic pesticide runoff model

    Science.gov (United States)

    Tang, Ting; Seuntjens, Piet; van Griensven, Ann; Bronders, Jan

    2016-04-01

    Urban areas can significantly contribute to pesticide contamination in surface water. However, pesticide behaviours in urban areas, particularly on hard surfaces, are far less studied than those in agricultural areas. Pesticide application on hard surfaces (e.g. roadsides and walkways) is of particular concern due to the high imperviousness and therefore high pesticide runoff potential. Experimental studies have shown that pesticide behaviours on and interactions with hard surfaces are important factors controlling the pesticide runoff potential, and therefore the magnitude and timing of peak concentrations in surface water. We conceptualized pesticide behaviours on hard surfaces and incorporated the conceptualization into a new pesticide runoff model. The pesticide runoff model was implemented in a catchment hydrological model WetSpa-Python (Water and Energy Transfer between Soil, Plants and Atmosphere, Python version). The conceptualization for pesticide processes on hard surfaces accounts for the differences in pesticide behaviour on different hard surfaces. Four parameters are used to describe the partitioning and wash-off of each pesticide on hard surfaces. We tested the conceptualization using experimental dataset for five pesticides on two types of hard surfaces, namely concrete and asphalt. The conceptualization gave good performance in accounting for the wash-off pattern for the modelled pesticides and surfaces, according to quantitative evaluations using the Nash-Sutcliffe efficiency and percent bias. The resulting pesticide runoff model WetSpa-PST (WetSpa for PeSTicides) can simulate pesticides and their metabolites at the catchment scale. Overall, it includes four groups of pesticide processes, namely pesticide application, pesticide interception by plant foliage, pesticide processes on land surfaces (including partitioning, degradation and wash-off on hard surface; partitioning, dissipation, infiltration and runoff in soil) and pesticide processes in

  16. Advantages and disadvantages of chemical oxidation and disinfection by ozone and chlorine dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Fiessinger, F.; Richard, Y.; Montiel, A.; Musquere, P.

    1981-04-01

    Ozone and chlorine dioxide present definite advantages and disadvantages over chlorination. Chlorination, particularly for the removal of ammonia and the maintenance of a disinfectant residual in the distribution system has decisive advantages and will be difficult to replace. Ozone and chlorine dioxide seem to produce fewer carcinogenic by-products but the risk for acute toxicity, especially from the chlorites which follow chlorine dioxide, is higher than with chlorine. Chlorine dioxide and more particularly ozone should be considered as useful complements to chlorination, but no strong oxidative treatment should be applied before most of the organic matter has been removed.

  17. UASB reactor effluent disinfection by ozone and chlorine

    NARCIS (Netherlands)

    Ribeiro da Silvia, G.H.; Bruning, H.; Gerrity, D.; Daniel, L.A.

    2015-01-01

    This research studied the sequential ozone and chlorine process with respect to, the inactivation of indicator bacteria and the formation of ozone disinfection byproducts in sanitary wastewater effluent. The applied ozone doses were 5, 8 and 10 mg.O3.L-1, followed by chlorine doses of 10, 20 and 30

  18. Chlorine Dioxide Induced Multiple Chemical Sensitivity: MMPI Validity Problems.

    Science.gov (United States)

    Tentoni, Stuart C.

    This paper discusses Minnesota Multiphasic Personality Inventory (MMPI) data obtained from individuals exposed to chlorine dioxide in the workplace who developed Multiple Chemical Sensitivity Syndrome. The paper explores current research on chlorine dioxide exposed persons who were misdiagnosed on the basis of MMPI interpretations. Difficulties…

  19. 78 FR 66767 - Chlorinated Isocyanurates From China and Japan

    Science.gov (United States)

    2013-11-06

    ... publishing the notice in the Federal Register of September 10, 2013 (78 FR 55293). The conference was held in... COMMISSION Chlorinated Isocyanurates From China and Japan Determinations On the basis of the record \\1... injured by reason of imports from China and Japan of chlorinated isocyanurates, provided for...

  20. Chlorine-containing natural compounds in higher plants

    DEFF Research Database (Denmark)

    Engvild, Kjeld Christensen

    1986-01-01

    More than 130 chlorine-containing compounds have been isolated from higher plants and ferns; about half are polyacetylenes, thiophenes and sesquiterpene lactones from the Asteraceae. A chlorinated chlorophyll may be an important part of photosystem 1. High biological activity is found in 4...

  1. Biodegradability of Chlorinated Anilines in Waters

    Institute of Scientific and Technical Information of China (English)

    CHAO WANG; GUAN-GHUA LU; YAN-JIE ZHOU

    2007-01-01

    Objective To identify the bacteria tolerating chlorinated anilines and to study the biodegradability of o-chloroaniline and its coexistent compounds. Methods Microbial community of complex bacteria was identified by plate culture observation techniques and Gram stain method. Bacterial growth inhibition test was used to determine the tolerance of complex bacteria to toxicant. Biodegradability of chlorinated anilines was determined using domesticated complex bacteria as an inoculum by shaking-flask test. Results The complex bacteria were identified, consisting of Xanthomonas, Bacillus alcaligenes,Acinetobacter, Pseudomonas, and Actinomycetaceae nocardia. The obtained complex bacteria were more tolerant to o-chloroaniline than mixture bacteria in natural river waters. The effects of exposure concentration and inoculum size on the biodegradability of o-chloroaniline were analyzed, and the biodegradation characteristics of single o-chloroaniline and 2,4-dichloroaniline were compared with the coexistent compounds. Conclusion The biodegradation rates can be improved by decreasing concentration of compounds and increasing inoculum size of complex bacteria. When o-chloroaniline coexists with aniline, the latter is biodegraded prior to the former, and as a consequence the metabolic efficiency of o-chloroaniline is improved with the increase of aniline concentration. Meanwhile, when o-chloroaniline coexists with 2,4-dichloroaniline, the metabolic efficiency of 2,4-dichloroaniline is markedly improved.

  2. Polychlorinated biphenyls and pesticides in surficial coastal sediments of the Ligurian Sea

    Energy Technology Data Exchange (ETDEWEB)

    Bertolotto, R.M.; Cuneo, C.; Albanese, S. [ARPAL, Direzione Scientifica, Genova (Italy); Magherini, A. [ARPAL, Dipartimento di Genova, Genova (Italy); Frignani, M.; Bellucci, L.G.; Alvarado-Aguilar, D. [ISMAR, Sezione di Geologia Marina, Bologna (Italy)

    2004-09-15

    Polychlorinated biphenyls (PCBs) and chlorinated pesticides, such as DDT and its analogues, are organic contaminants widespread throughout the terrestrial and oceanic environments due to their common use and their resistance to degradation. Since harmful effects have been associated to these chemicals and well documented, they are classified as priority pollutants by both the US Environmental Protection Agency (EPA) and the European Union. Because of the very low solubility in water and the tendency to adsorb onto sediment particles, the ultimate fate of both PCBs and DDTs in the marine environment is the incorporation into sediments. Hence, the concentrations of these chlorinate chemicals in bottom sediments can provide an insight on the quality of the environment and the potential threat to marine organisms and human beings. The Ligurian Sea belongs to the north part of the western Mediterranean. The coastal morphology of the Liguria Region is rather variable, and frequently cliffs drop sheer to the sea. The limited width of the coastal zone, comprised between the sea and the mountains, determined a gathering of the urban areas with a consequent concentration of both civil and industrial presence in a narrow but highly populated territory. In particular Genova, but also other cities have a long history of industrial and harbour activities, whereas long tracts of the coast are dedicated to tourism. The circulation of the Ligurian Sea is rather well known. In particular, surface and intermediate currents follow a cyclonic circulation. However local circulation is the true responsible of the dispersion of sediment material along the coast, and these alongshore currents often cause an eastward oriented transport. The Ligurian coastal zone is very developed, and hosts all sort of industrial, agricultural and tourist activities that can be sources of persistent organochlorine chemicals. Therefore, the purpose of this study was to assess concentrations, distributions

  3. Diterpenoid tetracyclic hydrocarbons of petroleum

    Energy Technology Data Exchange (ETDEWEB)

    Vorob' eva, N.S.; Zemskova, Z.K.; Pekh, T.I.; Petrov, A.A.

    1987-08-01

    Diterpenoid hydrocarbons are fairly widespread in various caustobioliths. However, if petroleums contain mainly acyclic diterpenoids (phytane, pristane and norpristane), cyclic diterpaenes such as fichtelite, pimarane, iosene (kaurane) and hibbane are often found in hydrocarbons isolated from coal and shale. Recent advances in the chemistry of diterpenoids isolated from caustobioliths, are described in a separate paper. Much less is known about petroleum polycyclic diterpenoid hydrocarbons, particularly those with four saturated rings. A series of tetracyclic hydrocarbons C/sub 19/H/sub 32/ (molar mass 260), found in a number of light petroleums and gas condensates from the Jura deposits of Central Kara-Kum (Turkmen S.S.R.), are examined here. These hydrocarbons are present in petroleums and condensates from the Davaly, Erden, Ortakak, Southern Beuideshik deposits, they are always identical and occur in the same ratios. The composition of the tretracyclanes isolated from the Ortakak gas condensates (well 17) will be examined in detail.

  4. Low-Cost Graphite-Based Free Chlorine Sensor.

    Science.gov (United States)

    Pan, Si; Deen, M Jamal; Ghosh, Raja

    2015-11-01

    Pencil lead was used to fabricate a graphite-based electrode for sensing applications. Its surface was electrochemically modified using ammonium carbamate to make it suitable for sensing free chlorine in water samples. Chlorine is widely used as a disinfectant in the water industry, and the residual free chlorine concentration in water distributed to the consumers must be lower than that stipulated by regulatory bodies. The graphite-based amperometric sensor gave a selective and linear response to free chlorine in the relevant concentration range and no response to commonly interfering ions. It was evaluated further for storage stability, response time, and hysteresis. This sensor is being proposed as a low-cost device for determining free chlorine in water samples. Its ease-of-use, limitations, and feasibility for mass-production and application is discussed.

  5. Production of alkyl aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Bonacci, J.C.; Billings, R.P.

    1975-01-30

    An improved method is claimed for producing aromatic hydrocarbons from a hydrocarbon charge containing aromatic hydrocarbons including benzene and C/sub 8/ alkyl aromatics and aliphatic hydrocarbons which charge is rich in such aromatic hydrocarbons and lean in aliphatic hydrocarbons boiling above about 220/sup 0/F by reason of conversion under severe conditions which comprises subjecting said charge to distillation conditions of temperature and pressure such that at least a portion of the benzene content of said fraction is separated as vapor from an alkyl aromatic fraction containing aliphatic hydrocarbons and the major portion of C/sub 8/ aromatics in said charge, reacting said alkyl aromatic fraction in the presence of hydrogen in contact with a catalyst containing type ZSM-5 zeolite, zeolite ZSM-12, zeolite ZSM-21 or zeolite beta in combination with a hydrogenation/dehydrogenation component at conversion conditions to convert aliphatic hydrocarbons to lower boiling material of five carbon atoms and lighter separable from aromatics by distillation including a temperature of about 500/sup 0/ to 1000/sup 0/F, a pressure of about 100 to about 600 pounds, a hydrogen to hydrocarbon mol ratio of 0.2 to 8 and weight hourly space velocity of 0.5 to 15, concurrently contacting a mixture of hydrogen and toluene with a disproportionation catalyst under reaction conditions to disproportionate said toluene, combining the effluents of said contacting steps, separating hydrogen from the combined effluents of said contacting steps, separating hydrogen from the combined effluents, recycling at least a portion of said separated hydrogen to said contacting steps, distilling the hydrocarbon residue from said separation step to recover therefrom at least toluene and mixed xylenes, and recycling at least a portion of said recovered toluene as feed to the disproportionation step aforesaid.

  6. Partitioning of organochlorine pesticides from water to polyethylene passive samplers

    Energy Technology Data Exchange (ETDEWEB)

    Hale, Sarah E., E-mail: sarah.hale@ncl.ac.u [School of Civil Engineering and Geosciences, Newcastle University, Newcastle upon Tyne, NE1 7RU (United Kingdom); Martin, Timothy J., E-mail: t.j.martin@ncl.ac.u [School of Civil Engineering and Geosciences, Newcastle University, Newcastle upon Tyne, NE1 7RU (United Kingdom); Goss, Kai-Uwe, E-mail: kai-uwe.goss@ufz.d [UFZ, Helmholtz Center for Environmental Research-UFZ, Permoserstrasse 15, 04318 Leipzig (Germany); Arp, Hans Peter H., E-mail: Hans.Peter.Arp@ngi.n [Department of Environmental Engineering, Norwegian Geotechnical Institute (NGI), P.O. Box 3930, Ulleval Stadion, N-0806, Oslo (Norway); Werner, David, E-mail: david.werner@ncl.ac.u [School of Civil Engineering and Geosciences, Newcastle University, Newcastle upon Tyne, NE1 7RU (United Kingdom)

    2010-07-15

    The mass transfer rates and equilibrium partitioning behaviour of 14 diverse organochlorine pesticides (OCP) between water and polyethylene (PE) passive samplers, cut from custom made PE sheets and commercial polyethylene plastic bags, were quantified. Overall mass transfer coefficients, k{sub O}, estimated PE membrane diffusion coefficients, D{sub PE}, and PE-water partitioning coefficients, K{sub PE-water,} are reported. In addition, the partitioning of three polycyclic aromatic hydrocarbons (PAHs) from water to PE is quantified and compared with literature values. K{sub PE-water} values agreed mostly within a factor of two for both passive samplers and also with literature values for the reference PAHs. As PE is expected to exhibit similar sorption behaviour to long-chain alkanes, PE-water partitioning coefficients were compared to hexadecane-water partitioning coefficients estimated with the SPARC online calculator, COSMOtherm and a polyparameter linear free energy relationship based on the Abraham approach. The best correlation for all compounds tested was with COSMOtherm estimated hexadecane-water partitioning coefficients. - The partitioning of organochlorine pesticides between single phase polyethylene passive samplers and water is quantified.

  7. Partitioning of organochlorine pesticides from water to polyethylene passive samplers

    International Nuclear Information System (INIS)

    The mass transfer rates and equilibrium partitioning behaviour of 14 diverse organochlorine pesticides (OCP) between water and polyethylene (PE) passive samplers, cut from custom made PE sheets and commercial polyethylene plastic bags, were quantified. Overall mass transfer coefficients, kO, estimated PE membrane diffusion coefficients, DPE, and PE-water partitioning coefficients, KPE-water, are reported. In addition, the partitioning of three polycyclic aromatic hydrocarbons (PAHs) from water to PE is quantified and compared with literature values. KPE-water values agreed mostly within a factor of two for both passive samplers and also with literature values for the reference PAHs. As PE is expected to exhibit similar sorption behaviour to long-chain alkanes, PE-water partitioning coefficients were compared to hexadecane-water partitioning coefficients estimated with the SPARC online calculator, COSMOtherm and a polyparameter linear free energy relationship based on the Abraham approach. The best correlation for all compounds tested was with COSMOtherm estimated hexadecane-water partitioning coefficients. - The partitioning of organochlorine pesticides between single phase polyethylene passive samplers and water is quantified.

  8. Effects of chlorine or chlorine dioxide during immersion chilling on recovery of bacteria from broiler carcasses and chiller water

    Science.gov (United States)

    A study was conducted to determine the microbiological impact of immersion chilling broiler carcasses with chlorine or chlorine dioxide. Eviscerated, pre-chill commercial broiler carcasses were cut into left and right halves along the keel bone, and each half was rinsed (HCR) in 100 mL of 0.1% pept...

  9. Change in genotoxicity of wastewater during chlorine dioxide and chlorine disinfections and the influence of ammonia nitrogen

    Institute of Scientific and Technical Information of China (English)

    WANG Lisha; HU Hongying; WANG Chao; Koichi Fujie

    2007-01-01

    The effects of chlorine dioxide and chlorine disinfections on the genotoxicity of different biologically treated sewage wastewater samples were studied by umu-test.The experiment results showed that when chlorine dioxide dosage was increased from 0 to 30 mg/L,the genotoxicity of wastewater first decreased rapidly and then tended to be stable,while when the chlorine dosage was increased from 0 to 30 mg/L,the genotoxicity of wastewater changed diversely for different samples.It was then found that ammonia nitrogen did not affect the change of genotoxicity during chlorine dioxide disinfection of wastewater,while it greatly affected the change of genotoxicity during chlorine disinfection of wastewater.When the concentration of ammonia nitrogen was low(<10-20mg/L),the genotoxicity of wastewater decreased after chlorine disinfection,and when the concentration of ammonia nitrogen was high(>10-20 mg/L),the genotoxicity of wastewater increased after chlorine disinfection.

  10. Synergetic Inactivation of Microorganisms in Drinking Water by Short-term Free Chlorination and Subsequent Monochloramination

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    To introduce synergetic inactivation of microorganisms in drinking water by short-term free chlorination for less than 15 minutes followed by monochloramination. Methods Indicator microorganisms such as Escherichia coli,Staphylococcus aureus, Candida albicans, and spores of Bacillus subtilis were used to assess the efficiency of sequential chlorination and free chlorination. Results The sequential chlorination was more efficient in inactivating these microorganisms than free chlorination, indicating that synergy was provided by free chlorine and monochloramine. Ammonia addition time, temperature and pH had influences on this synergy. Conclusion The possible mechanism of this synergy might involve three aspects: free chlorine causing sublethal injury to microorganisms and monochloramine further inactivating them; different ability of free chlorine and monochloramine to penetrate and inactivate microorganism congeries; and higher concentration of residual chlorine in sequential chlorination than in free chlorination.

  11. COMMUNICATING THE RISKS OF PESTICIDE EXPOSURE TO AGRICULTURAL WORKERS

    Science.gov (United States)

    The goals of the USEPA pesticide worker safety program are to protect human health and the environment by ensuring the competency of pesticide applicators to minimize pesticide exposure to occupational pesticide users and agricultural field workers, to assure use of pesticides, a...

  12. 40 CFR 170.230 - Pesticide safety training for handlers.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Pesticide safety training for handlers...) PESTICIDE PROGRAMS WORKER PROTECTION STANDARD Standard for Pesticide Handlers § 170.230 Pesticide safety... of restricted-use pesticides under part 171 of this chapter. (2) A handler who satisfies the...

  13. Pesticides and their effects on wildlife

    Energy Technology Data Exchange (ETDEWEB)

    Driver, C.J.

    1994-07-01

    About 560 active ingredients are currently used as pesticides. Applications of these pesticides are made to agricultural lands and other areas inhabited by wildlife. Unfortunately, many agricultural-use pesticides also entail some measure of risk to organisms other than the pest species. Because testing of pesticides prior to registration cannot evaluate all the potential environmental-pesticide-wildlife/fish interactions, current methods of risk assessment do not always provide sufficient safety to nontarget organisms. This is evidenced by die-offs of fish and wildlife from applications of pesticides at environmentally {open_quotes}safe{close_quotes} rates, the linking of population declines of some species with agrochemical use, and observations of survival-threatening behavioral changes in laboratory and field animals exposed to typical field levels of pesticides. It is important to note, however, that the majority of pesticides, when properly applied, have not caused significant injury to wildlife. A brief summary of pesticide effects on wildlife and fish are presented for the common classes of pesticides in use today.

  14. The use and disposal of household pesticides.

    Science.gov (United States)

    Grey, Charlotte N B; Nieuwenhuijsen, Mark J; Golding, Jean

    2005-01-01

    Most pesticides are synthetic chemicals manufactured specifically for their toxic properties to the target species, and widely used globally. Several epidemiological studies in the United States have suggested health concerns arising from the chronic exposure of young children to pesticides in the domestic environment. In the UK very little is currently known about how nonoccupational pesticides are being used or disposed of. Any use of pesticides is a potential risk factor for children's exposure, and any potential exposure is likely to be reduced by the parents' adopting precautionary behaviour when using these pesticide products. This was investigated using a sample of 147 parents from the Avon Longitudinal Study of Parents and Children cohort in and around Bristol, through an in-depth interview between August and November 2001. The results of this study add to the understanding of the underlying behaviour of parents applying pesticide products in the home environment in the UK. Pesticides are readily available, and are normally purchased in do-it-yourself shops and supermarkets and mostly disposed of in domestic waste. Safety was stated by 45% of parents to be the most important factor to consider when buying a pesticide. When buying pesticide products, labels were stated to be the most important source of information about pesticides. However, a third of parents stated they would not follow the product label exactly when using a product, just under half felt labels were both inadequate and hard to understand, and about 10% of parents would not take notice of warnings on the pesticide label. Less than half of parents would use gloves when applying a pesticide, although the use of protective equipment such as gloves during the application of pesticides could greatly reduce the exposure. It is a public health concern that the instructions on the labels of products may not always be understood or followed, and further understanding of user behaviour is needed.

  15. The use and disposal of household pesticides

    International Nuclear Information System (INIS)

    Most pesticides are synthetic chemicals manufactured specifically for their toxic properties to the target species, and widely used globally. Several epidemiological studies in the United States have suggested health concerns arising from the chronic exposure of young children to pesticides in the domestic environment. In the UK very little is currently known about how nonoccupational pesticides are being used or disposed of. Any use of pesticides is a potential risk factor for children's exposure, and any potential exposure is likely to be reduced by the parents' adopting precautionary behaviour when using these pesticide products. This was investigated using a sample of 147 parents from the Avon Longitudinal Study of Parents and Children cohort in and around Bristol, through an in-depth interview between August and November 2001. The results of this study add to the understanding of the underlying behaviour of parents applying pesticide products in the home environment in the UK. Pesticides are readily available, and are normally purchased in do-it-yourself shops and supermarkets and mostly disposed of in domestic waste. Safety was stated by 45% of parents to be the most important factor to consider when buying a pesticide. When buying pesticide products, labels were stated to be the most important source of information about pesticides. However, a third of parents stated they would not follow the product label exactly when using a product, just under half felt labels were both inadequate and hard to understand, and about 10% of parents would not take notice of warnings on the pesticide label. Less than half of parents would use gloves when applying a pesticide, although the use of protective equipment such as gloves during the application of pesticides could greatly reduce the exposure. It is a public health concern that the instructions on the labels of products may not always be understood or followed, and further understanding of user behaviour is needed

  16. Appraisal of chlorine contact tank modelling practices.

    Science.gov (United States)

    Rauen, William B; Angeloudis, Athanasios; Falconer, Roger A

    2012-11-15

    With new water directives imposing strict regulations to reduce the footprint of treatment operations and contaminant levels, a performance review of water treatment facilities, including Chlorine Contact Tanks (CCTs) is required. This paper includes a critical appraisal of the international literature on CCT modelling practices to date, aiming to assist the identification of areas requiring further development, in particular, relating to the computational modelling capability and availability of tools to assist hydraulic design and optimisation studies of CCTs. It notes that the hydraulic optimisation practice of poorly designed tanks commenced with experimental studies undertaken in the 1960s and 1970s, which involved mainly two types of studies, namely in situ tracer tests and laboratory physical modelling. The former has traditionally been conducted to diagnose the hydraulic performance of existing CCTs, typically based on results such as Residence Time Distribution (RTD) curves and values of the Hydraulic Efficiency Indicators (HEIs). The latter has been useful in trial and error testing of the impact of certain design modifications on those results, with suggestions for later improvements of the field scale unit. In the 1980s mathematical and numerical modelling studies started to be used to assist CCT investigations, offering a greater level of detail in a more cost-effective manner than equivalent experimentally based investigations. With the growth of computing power and the popularisation of computational models, the 1990s saw the development and application of Computational Fluid Dynamics (CFD) tools to simulate the hydraulic performance of CCTs, sometimes independently of experimentation, other than by using available data to calibrate and validate modelling predictions. This has led to the current scenario of CFD models being invaluable assistive tools in optimisation studies of CCTs, with the experimentation practice continuing to allow for specific

  17. Ultrafast measurements of chlorine dioxide photochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Ludowise, P.D.

    1997-08-01

    Time-resolved mass spectrometry and time-resolved photoelectron spectroscopy are used to study the ultrafast photodissociation dynamics of chlorine dioxide, an important constituent in stratospheric ozone depletion. Chapter 1 introduces these pump/probe techniques, in which a femtosecond pump pulse excites a molecule to a dissociative state. At a later time, a second femtosecond probe pulse ionizes the molecule. The resulting mass and photoelectron spectra are acquired as a function of the delay between the pump and probe pulses, which follows the evolution of the molecule on the excited state. A comparison to other techniques used to study reaction dynamics is discussed. Chapter 2 includes a detailed description of the design and construction of the experimental apparatus, which consists of a femtosecond laser system, a molecular beam time-of-flight spectrometer, and a data acquisition system. The time-of-flight spectrometer is specifically designed to have a short flight distance to maximize the photoelectron collection efficiency without degrading the resolution, which is limited by the bandwidth of the femtosecond laser system. Typical performance of the apparatus is demonstrated in a study of the time-resolved photoelectron spectroscopy of nitric oxide. The results of the time-resolved mass spectrometry experiments of chlorine dioxide are presented in Chapter 3. Upon excitation to the A {sup 2}A{sub 2} state near 3.2 eV, the molecule dissociates through an indirect two-step mechanism. The direct dissociation channel has been predicted to be open, but is not observed. A quantum beat is observed in the OClO{sup +} species, which is described as a vibrational coherence of the optically prepared A {sup 2}A{sub 2} state. Chapter 4 presents the results of the time-resolved photoelectron experiments of chlorine dioxide. At short delay time, the quantum beat of the OClO{sup +} species is observed in the X {sup 1}A{sub 1} state of the ion. At infinite delay, the signal

  18. Chlorine Isotopes: As a Possible Tracer of Fluid/Bio-Activities on Mars and a Progress Report on Chlorine Isotope Analysis by TIMs

    Science.gov (United States)

    Nakamura, N.; Nyquist, L.E.; Reese, Y.; Shih, C-Y.; Numata, M.; Fujitani, T.; Okano, O.

    2009-01-01

    Significantly large mass fractionations between chlorine isotopes (Cl-35, Cl-37) have been reported for terrestrial materials including both geological samples and laboratory materials. Also, the chlorine isotopic composition can be used as a tracer for early solar system processes. Moreover, chlorine is ubiquitous on the Martian surface. Typical chlorine abundances in Gusev soils are approx.0.5 %. The global surface average chlorine abundance also is approx.0.5 %. Striking variations among outcrop rocks at Meridiani were reported with some chlorine abundances as high as approx.2%. Characterizing conditions under which chlorine isotopic fractionation may occur is clearly of interest to planetary science. Thus, we have initiated development of a chlorine isotopic analysis technique using TIMS at NASA-JSC. We present here a progress report on the current status of development at JSC and discuss the possible application of chlorine isotopic analysis to Martian meteorites in a search for fluid- and possibly biological activity on Mars.

  19. Chlorination of calcium tungstate by mixture of chlorine and sulfur dioxide

    International Nuclear Information System (INIS)

    Results of thermodynamic calculations and experimental investigations of interaction of calcium tungstate with Cl2+SO2 mixture at 400-850 deg C are presented. It is shown that the processes passes through several sequential and parallel stages with formation of tungsten (6) oxide and calcium chloride as intermediate products. Peculiarities of the process are determined by the ratio of rates of WO3 formation and chlorination stages

  20. Assessment of organochlorine pesticides residues in higher plants from oil exploration areas of Niger Delta, Nigeria.

    Science.gov (United States)

    Sojinu, O Samuel; Sonibare, Oluwadayo O; Ekundayo, Olusegun O; Zeng, Eddy Y

    2012-09-01

    The concentrations and distributions of organochlorine pesticides (OCPs) in some higher plant samples collected from oil exploration areas of the Niger Delta, Nigeria were examined. The concentrations of Σ(25)OCP ranged from 82 to 424, 44 to 200 , 34 to 358, 33 to 106 and 16 to 75 ng/g in Olomoro, Oginni, Uzere, Irri and Calabar plants, respectively. The compositional profiles of the analysed OCPs in most of the plants showed no fresh inputs in the area. The OCPs detected in the samples could have resulted from pesticide usage for intense farming activities cum the use of pesticides to control household pests and insects in the area. Drilling fluids and corrosion inhibitors used in petroleum explorations also have chlorinated compounds as additives thereby serving as potential sources of OCPs. Among the studied plants, elephant grass showed high bioaccumulation and phytoremediation potentials of OCPs. The ΣHCH concentrations exceeded the allowable daily intake limit thereby serving as potential threat to humans. PMID:22789817

  1. Bench scale studies: Ozonation as a potential treatment for waters contaminated with hydrocarbons or dioxins and furans

    International Nuclear Information System (INIS)

    The objective of the bench scale studies was to examine the destruction efficiency and efficacy of ozone on chemicals of concern (COC's) commonly found in contaminated ground water and rhenoformer wash water. The ground water used in these tests contained aromatic petroleum hydrocarbons, chlorinated hydrocarbons, and mineral spirits. The rhenoformer wash water used in these tests contained a variety of dioxins (including 2,3,7,8-tetrachlorodibenzo-p-dioxin) and furans. Summaries are presented of the bench scale studies by describing the COCs, methodologies, test reactors, observations, and results. The summaries also detail which applications hold promise with respect to ozonation and which ones do not. Bench test results for the experiments in which aromatic petroleum hydrocarbons, chlorinated hydrocarbons, and mineral spirits where the COCs were relatively successful. Concentrations for the COCs ranging from 300 to 3,400 micrograms per liter (microg/L) were brought below levels specified for storm sewer discharge per the National Priority Discharge Elimination Systems (NPDES) permit requirements. Bench test results for the experiments in which dioxins and furans were the COCs were less promising and revealed that additional processes would have to be used in conjunction with ozonation to bring the concentration of COCs within the targeted ranges. It was realized, however, that the effectiveness and efficacy of ozonation were diminished by the presence of particulates, to which some of the dioxin and furan compounds adhered

  2. Enhancement of in situ Remediation of Hydrocarbon Contaminated Soil

    Energy Technology Data Exchange (ETDEWEB)

    Palmroth, M.

    2006-07-01

    Approximately 750 000 sites of contaminated land exist across Europe. The harmful chemicals found in Finnish soils include heavy metals, oil products, polyaromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), chlorophenols, and pesticides. Petroleum and petroleum products enter soil from ruptured oil pipelines, land disposal of refinery products, leaking storage tanks and through accidents. PAH contamination is caused by the spills of coal tar and creosote from coal gasification and wood treatment sites in addition to oil spills. Cleanup of soil by bioremediation is cheaper than by chemical and physical processes. However, the cleaning capacity of natural attenuation and in situ bioremediation is limited. The purpose of this thesis was to find feasible options to enhance in situ remediation of hydrocarbon contaminants. The aims were to increase the bioavailability of the contaminants and microbial activity at the subsurface in order to achieve higher contaminant removal efficiency than by intrinsic biodegradation alone. Enhancement of microbial activity and decrease of soil toxicity during remediation were estimated by using several biological assays. The performance of these assays was compared in order to find suitable indicators to follow the progress of remediation. Phytoremediation and chemical oxidation are promising in situ techniques to increase the degradation of hydrocarbons in soil. Phytoremediation is plant-enhanced decontamination of soil and water. Degradation of hydrocarbons is enhanced in the root zone by increased microbial activity and through the detoxifying enzymes of plants themselves. Chemical oxidation of contaminants by Fenton's reaction can produce degradation products which are more biodegradable than the parent compounds. Fenton's reaction and its modifications apply solutions of hydrogen peroxide and iron for the oxidation of organic chemicals. The cost of oxidation can be reduced by aiming at partial instead of full

  3. Corrosion of copper by chlorine trifluoride

    International Nuclear Information System (INIS)

    The research described called for a considerable amount of preliminary development of the test methods and equipment in order that the various measurements and observations could be carried out without contaminating either the samples or this highly reactive gas. The chlorine trifluoride was highly purified before use, its purity being checked by gas-phase chromatography, micro-sublimation and infrared spectrography. The tests were carried out on copper samples of various purities, in particular a 99.999 per cent copper in the form of mono-crystals. They involved kinetic measurements and the characterization of corrosion products under different temperature and pressure conditions. The kinetics showed reactions of the same order of magnitude as those obtained with elementary fluorine. At atmospheric pressure there occurs formation of cupric fluoride and cuprous chloride. The presence of this latter product shows that it is not possible to consider ClF3 simply as a fluorinating agent. At low pressures an unknown product has been characterized. There are strong grounds for believing that it is the unstable cuprous fluoride which it has not yet been possible to isolate. A germination phenomenon has been shown to exist indicating an analogy between the initial phases of fluorination and those of oxidation. Important effects resulting from the dissociation of the copper fluorides and the solubility of chlorine in this metal have been demonstrated. Finally, tests have shown the considerable influence of the purity of the gas phase and of the nature of the reaction vessel walls on the rates of corrosion which can in certain cases be increased by a factor of several powers of ten. (author)

  4. Thermal and under irradiation diffusion of chlorine in uranium dioxide

    International Nuclear Information System (INIS)

    This work concerns the study of the thermal and radiation enhanced diffusion of 36Cl in uranium dioxide. We simulated the presence of 36Cl by implanting a quantity of 37Cl comparable to the impurity content of chlorine in UO2. In order to evaluate the diffusion properties of chlorine in the fuel and in particular to assess the influence of the irradiation defects, we performed two kinds of experiments: - the influence of the temperature was studied by carrying out thermal annealings in the temperature range 900 - 1300 C; we showed that implanted chlorine was mobile from temperatures as low as 1000 C and determined a thermal diffusion coefficient D1000 C around 10-16 cm2s-1 - the influence of the irradiation by fission products were studied by irradiating the samples with 127I (energy of 63.5 MeV). We could determine that the diffusion of the implanted chlorine under irradiation and in the range of temperature 30 - 250 C was not purely athermal. We calculated a diffusion coefficient under irradiation D250 C of about 0-14 cm2.s-1. We showed the importance of the implantation and irradiation defects as preferential paths for a fast chlorine transport. We carried out ab initio calculations showing that chlorine is preferentially located in a substitutional site. This is in favour of a Frank-Turnbull diffusion mechanism or a vacancy/chlorine. (author)

  5. Does chlorination of seawater reverse osmosis membranes control biofouling?

    Science.gov (United States)

    Khan, Muhammad Tariq; Hong, Pei-Ying; Nada, Nabil; Croue, Jean Philippe

    2015-07-01

    Biofouling is the major problem of reverse osmosis (RO) membranes used for desalting seawater (SW). The use of chlorine is a conventional and common practice to control/prevent biofouling. Unlike polyamide RO membranes, cellulose triacetate (CTA) RO membranes display a high chlorine tolerance. Due to this characteristic, CTA membranes are used in most of the RO plants located in the Middle East region where the elevated seawater temperature and water quality promote the risk of membrane biofouling. However, there is no detailed study on the investigation/characterization of CTA-RO membrane fouling. In this investigation, the fouling profile of a full-scale SWRO desalination plant operating with not only continuous chlorination of raw seawater but also intermittent chlorination of CTA-RO membranes was studied. Detailed water quality and membrane fouling analyses were conducted. Profiles of microbiological, inorganic, and organic constituents of analysed fouling layers were extensively discussed. Our results clearly identified biofilm development on these membranes. The incapability of chlorination on preventing biofilm formation on SWRO membranes could be assigned to its failure in effectively reaching throughout the different regions of the permeators. This failure could have occurred due to three main factors: plugging of membrane fibers, chlorine consumption by organics accumulated on the front side fibers, or chlorine adaptation of certain bacterial populations. PMID:25917390

  6. Does Chlorination of Seawater Reverse Osmosis Membranes Control Biofouling?

    KAUST Repository

    Khan, Muhammad Tariq

    2015-04-01

    Biofouling is the major problem of reverse osmosis (RO) membranes used for desalting seawater (SW). The use of chlorine is a conventional and common practice to control/prevent biofouling. Unlike polyamide RO membranes, cellulose triacetate (CTA) RO membranes display a high chlorine tolerance. Due to this characteristic, CTA membranes are used in most of the RO plants located in the Middle East region where the elevated seawater temperature and water quality promote the risk of membrane biofouling. However, there is no detailed study on the investigation/characterization of CTA-RO membrane fouling. In this investigation, the fouling profile of a full–scale SWRO desalination plant operating with not only continuous chlorination of raw seawater but also intermittent chlorination of CTA-RO membranes was studied. Detailed water quality and membrane fouling analyses were conducted. Profiles of microbiological, inorganic, and organic constituents of analysed fouling layers were extensively discussed. Our results clearly identified biofilm development on these membranes. The incapability of chlorination on preventing biofilm formation on SWRO membranes could be assigned to its failure in effectively reaching throughout the different regions of the permeators. This failure could have occurred due to three main factors: plugging of membrane fibers, chlorine consumption by organics accumulated on the front side fibers, or chlorine adaptation of certain bacterial populations.

  7. Does chlorination of seawater reverse osmosis membranes control biofouling?

    Science.gov (United States)

    Khan, Muhammad Tariq; Hong, Pei-Ying; Nada, Nabil; Croue, Jean Philippe

    2015-07-01

    Biofouling is the major problem of reverse osmosis (RO) membranes used for desalting seawater (SW). The use of chlorine is a conventional and common practice to control/prevent biofouling. Unlike polyamide RO membranes, cellulose triacetate (CTA) RO membranes display a high chlorine tolerance. Due to this characteristic, CTA membranes are used in most of the RO plants located in the Middle East region where the elevated seawater temperature and water quality promote the risk of membrane biofouling. However, there is no detailed study on the investigation/characterization of CTA-RO membrane fouling. In this investigation, the fouling profile of a full-scale SWRO desalination plant operating with not only continuous chlorination of raw seawater but also intermittent chlorination of CTA-RO membranes was studied. Detailed water quality and membrane fouling analyses were conducted. Profiles of microbiological, inorganic, and organic constituents of analysed fouling layers were extensively discussed. Our results clearly identified biofilm development on these membranes. The incapability of chlorination on preventing biofilm formation on SWRO membranes could be assigned to its failure in effectively reaching throughout the different regions of the permeators. This failure could have occurred due to three main factors: plugging of membrane fibers, chlorine consumption by organics accumulated on the front side fibers, or chlorine adaptation of certain bacterial populations.

  8. Removal effect on Mesocyclops leukarti and mutagenicity with chlorine dioxide

    Institute of Scientific and Technical Information of China (English)

    ZUO Jin-long; CUI Fu-yi; QU Bo; ZHU Gui-bing

    2006-01-01

    Mesocyclops leukarti of zooplankton propagates excessively in eutrophic water body and it cannot be effectively inactivated by the conventional drinking water treatment process. In order to tackle this problem, a study of removal effect on Mesocyclops leukarti with chlorine dioxide in a waterworks was performed. The results showed that Mesocyclops leukarti could be effectively removed from water by 1.0 mg/L chlorine dioxide preoxidation combined with the conventional drinking water treatment process.Higher oxidizability and molecular state of chlorine dioxide in water is the key to the inactivation of Mesocyclops leukarti. The chlorite, disinfection by-products (DBPs) of chlorine dioxide, was stable at 0.45 mg/L, which is lower than that critical value of the USEPA. GC-MS examination showed that the quantity of organic substance in the water treated by chlorine dioxide obviously decreased. Ames test further revealed that the mutagenicity was reduced by chlorine dioxide with respect to prechlorine. The propagation ofMesocyclops leukarti can be inactivated effectively and safely by chlorine dioxide pre-oxidation.

  9. Fate of pesticides during beer brewing.

    Science.gov (United States)

    Inoue, Tomonori; Nagatomi, Yasushi; Suga, Keiko; Uyama, Atsuo; Mochizuki, Naoki

    2011-04-27

    The fates of more than 300 pesticide residues were investigated in the course of beer brewing. Ground malt artificially contaminated with pesticides was brewed via steps such as mashing, boiling, and fermentation. Analytical samples were taken from wort, spent grain, and beer produced at certain key points in the brewing process. The samples were extracted and purified with the QuEChERS (Quick Easy Cheap Effective Rugged and Safe) method and were then analyzed by LC-MS/MS using a multiresidue method. In the results, a majority of pesticides showed a reduction in the unhopped wort and were adsorbed onto the spent grain after mashing. In addition, some pesticides diminished during the boiling and fermentation. This suggests that the reduction was caused mainly by adsorption, pyrolysis, and hydrolysis. After the entire process of brewing, the risks of contaminating beer with pesticides were reduced remarkably, and only a few pesticides remained without being removed or resolved.

  10. Characterizing pesticide dissipation in food crops

    DEFF Research Database (Denmark)

    Fantke, Peter; Juraske, R.; Jolliet, O.

    2013-01-01

    Ingestion of residues via consumption of food crops is the predominant exposure route of the general population toward pesticides. However, pesticide dissipation in crops constitutes a main source of uncertainty in estimating residues in harvested crop parts and subsequent human exposure. Neverth......Ingestion of residues via consumption of food crops is the predominant exposure route of the general population toward pesticides. However, pesticide dissipation in crops constitutes a main source of uncertainty in estimating residues in harvested crop parts and subsequent human exposure....... Nevertheless, dissipation is a key mechanism in models assessing pesticide distribution in the cropenvironment and the magnitude of residues in harvest. We provide a consistent framework for characterizing pesticide dissipation in food crops for use in modeling approaches applied in health risk and impact...

  11. Behavior and stability of adenosine triphosphate (ATP) during chlorine disinfection.

    Science.gov (United States)

    Nescerecka, Alina; Juhna, Talis; Hammes, Frederik

    2016-09-15

    Adenosine triphosphate (ATP) analysis is a cultivation-independent alternative method for the determination of bacterial viability in both chlorinated and non-chlorinated water. Here we investigated the behavior and stability of ATP during chlorination in detail. Different sodium hypochlorite doses (0-22.4 mg-Cl2 L(-1); 5 min exposure) were applied to an Escherichia coli pure culture suspended in filtered river water. We observed decreasing intracellular ATP with increasing chlorine concentrations, but extracellular ATP concentrations only increased when the chlorine dose exceeded 0.35 mg L(-1). The release of ATP from chlorine-damaged bacteria coincided with severe membrane damage detected with flow cytometry (FCM). The stability of extracellular ATP was subsequently studied in different water matrixes, and we found that extracellular ATP was stable in sterile deionized water and also in chlorinated water until extremely high chlorine doses (≤11.2 mg-Cl2 L(-1); 5 min exposure). In contrast, ATP decreased relatively slowly (k = 0.145 h(-1)) in 0.1 μm filtered river water, presumably due to degradation by either extracellular enzymes or the fraction of bacteria that were able to pass through the filter. Extracellular ATP decreased considerably faster (k = 0.368 h(-1)) during batch growth of a river water bacterial community. A series of growth potential tests showed that extracellular ATP molecules were utilized as a phosphorus source during bacteria proliferation. From the combined data we conclude that ATP released from bacteria at high chlorine doses could promote bacteria regrowth, contributing to biological instability in drinking water distribution systems. PMID:27295623

  12. Behavior and stability of adenosine triphosphate (ATP) during chlorine disinfection.

    Science.gov (United States)

    Nescerecka, Alina; Juhna, Talis; Hammes, Frederik

    2016-09-15

    Adenosine triphosphate (ATP) analysis is a cultivation-independent alternative method for the determination of bacterial viability in both chlorinated and non-chlorinated water. Here we investigated the behavior and stability of ATP during chlorination in detail. Different sodium hypochlorite doses (0-22.4 mg-Cl2 L(-1); 5 min exposure) were applied to an Escherichia coli pure culture suspended in filtered river water. We observed decreasing intracellular ATP with increasing chlorine concentrations, but extracellular ATP concentrations only increased when the chlorine dose exceeded 0.35 mg L(-1). The release of ATP from chlorine-damaged bacteria coincided with severe membrane damage detected with flow cytometry (FCM). The stability of extracellular ATP was subsequently studied in different water matrixes, and we found that extracellular ATP was stable in sterile deionized water and also in chlorinated water until extremely high chlorine doses (≤11.2 mg-Cl2 L(-1); 5 min exposure). In contrast, ATP decreased relatively slowly (k = 0.145 h(-1)) in 0.1 μm filtered river water, presumably due to degradation by either extracellular enzymes or the fraction of bacteria that were able to pass through the filter. Extracellular ATP decreased considerably faster (k = 0.368 h(-1)) during batch growth of a river water bacterial community. A series of growth potential tests showed that extracellular ATP molecules were utilized as a phosphorus source during bacteria proliferation. From the combined data we conclude that ATP released from bacteria at high chlorine doses could promote bacteria regrowth, contributing to biological instability in drinking water distribution systems.

  13. Chlorine isotope evidence for the anthropogenic origin of tris-(4-chlorophenyl)methane

    Energy Technology Data Exchange (ETDEWEB)

    Holmstrand, Henry, E-mail: henry.holmstrand@itm.su.se [Department of Applied Environmental Science (ITM), Stockholm University, 10691 Stockholm (Sweden); Zencak, Zdenek [Department of Applied Environmental Science (ITM), Stockholm University, 10691 Stockholm (Sweden); Mandalakis, Manolis [Department of Applied Environmental Science (ITM), Stockholm University, 10691 Stockholm (Sweden)] [Environmental Chemical Processes Laboratory (ECPL), University of Crete, 71003 Heraklion (Greece); Andersson, Per [Laboratory for Isotope Geology (LIG), Swedish Museum of Natural History, 10405 Stockholm (Sweden); Gustafsson, Orjan [Department of Applied Environmental Science (ITM), Stockholm University, 10691 Stockholm (Sweden)

    2010-09-15

    Research highlights: {yields} TCPMe is a bioaccumulating organochlorine found at significant levels in organisms at high trophic levels, e.g. birds and mammals. {yields} Previous investigations have suggested TCPMe being co-released as a trace byproduct in pesticides such as DDT. {yields} The results from compound-specific chlorine isotope analysis of TCPMe supports the hypothesis that the source of TCPMe is indeed the extensive historical use of DDT. - Abstract: Compound-specific Cl-isotope analysis was performed on the persistent and bioaccumulating compound tris-(4-chlorophenyl)methane (4,4',4''-TCPMe, referred to as TCPMe in this study) to elucidate whether its main source is natural or anthropogenic. Blubber from the Baltic grey seal (Halichoerus grypus) was extracted by continuous acetonitrile partitioning, and the TCPMe was isolated from the extract by preparative-capillary gas chromatography. Chlorine isotope analysis was subsequently performed by sealed-tube combustion in conjunction with thermal-ionization mass spectrometry (TIMS). The {delta}{sup 37}Cl of TCPMe was -3.5 {+-} 0.5 per mille, similar to the previously reported {delta}{sup 37}Cl of technical grade p,p'-DDT (referred to as DDT in this study). The data is not consistent with a putative marine natural source of TCPMe, as enzymatic (biotic) production is reported to give values of {delta}{sup 37}Cl < -10 per mille. The {delta}{sup 37}Cl-TCPMe data thus supports the hypothesis that TCPMe is produced as a byproduct during DDT synthesis and is released to the environment through the same pathways as DDT. It is also consistent with tris-(4-chlorophenyl)methanol as the primary biotransformation product of TCPMe.

  14. Managing Pesticide Risks for Non-Target Ecosystems with Pesticide Risk Indicators: a Multicriteria Approach

    OpenAIRE

    Travisi, Chiara Maria; NIJKAMP Peter; Vighi, Marco; Giacomelli, Paolo

    2004-01-01

    In the search for effective pesticide risk management tools, the design of pesticide risk indicators is nowadays receiving increasing attention as a complement to more established regulatory strategies. In the present paper, we apply some recently developed pesticide risk indices and test their potential for management purposes. A pilot approach is proposed, which explores pesticide worst-case hazard scenarios at different space-time scales by means of a set of 5 ecotoxicological risk indices...

  15. Governing pesticide in vegetable production in Vietnam

    OpenAIRE

    Hoi, Van, P.

    2010-01-01

    The economic liberalization in Vietnam, initiated in the middle of the 1980s, contributed to the further intensification and expansion of private actor-engagement in agriculture and food-supply. Vietnamese farmers, who already considered applying pesticides the most effective manner to protect their vegetable crops from pests and disease attacks, started using more pesticides. Pesticide use in agriculture has, therefore, increased astonishingly in recent decades which causes increasing anxiet...

  16. Monitoring of pesticides in human milk

    International Nuclear Information System (INIS)

    After establishing proper analytical methodology for multiple pesticide residues, cotton-growing areas of Multan Division of Pakistan were surveyed and 40 samples of human milk from cotton pickers were collected during two crop seasons. Screening of these samples showed 72.5% contamination with 19 different pesticides/metabolites. The most frequently occurring pesticides were DDT and its metabolites, dimethoate, cyhalothrin, monocrotophos, profenofos and quinalphos. (author)

  17. Free Trade, Pesticide Regulation and NAFTA Harmonization

    OpenAIRE

    Freshwater, David

    2003-01-01

    Pesticides are an important farm input both in terms of cost and in terms of their impact on crop yields and quality. With freer trade in agricultural output, differences in cost of production, yield and quality can have a large effect on competitiveness. Thus there is an increased demand by farmers in Canada and the United States for harmonization of pesticide regulations, and in particular for the option to import registered pesticides for their own use. Under NAFTA the three national gover...

  18. Pesticides reduce regional biodiversity of stream invertebrates

    OpenAIRE

    Beketov, Mikhail A.; Kefford, Ben J.; Schäfer, Ralf B.; Liess, Matthias

    2013-01-01

    The biodiversity crisis is one of the greatest challenges facing humanity, but our understanding of the drivers remains limited. Thus, after decades of studies and regulation efforts, it remains unknown whether to what degree and at what concentrations modern agricultural pesticides cause regional-scale species losses. We analyzed the effects of pesticides on the regional taxa richness of stream invertebrates in Europe (Germany and France) and Australia (southern Victoria). Pesticides caused ...

  19. Effect of Endocrine Disruptor Pesticides: A Review

    OpenAIRE

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

    2011-01-01

    Endocrine disrupting chemicals (EDC) are compounds that alter the normal functioning of the endocrine system of both wildlife and humans. A huge number of chemicals have been identified as endocrine disruptors, among them several pesticides. Pesticides are used to kill unwanted organisms in crops, public areas, homes and gardens, and parasites in medicine. Human are exposed to pesticides due to their occupations or through dietary and environmental exposure (water, soil, air). For several yea...

  20. Proceedings of hydrocarbon contaminated soils and groundwater

    International Nuclear Information System (INIS)

    This book reports on hydrogen contaminated soils and groundwater. Topics covered include: perspectives on hydrocarbon contamination; emerging hydrocarbon contamination issues; analytical methodologies and site assessment for hydrocarbon contaminated soils and groundwater; environmental fate and modeling; remedial technologies for hydrocarbon contaminated soils and groundwater; and risk assessment and risk management

  1. Effect of sulfur dioxide on indium (3) oxide chlorination

    International Nuclear Information System (INIS)

    On the basis of thermodynamic calculations and kinetic investigations, it is established that in the temperature range from 550 to 800 deg C in the In2O3-Cl2-SO2 system coupled reactions of InCl3 and In2(SO4)3 formation accompanying by further In2(SO4)3 chlorination with gaseous chlorine are main processes, SO2 accelerates considerably In2O3 chlorination at a temperature below 800 deg C, its influence on the process of chloride sublimation at a temperature higher than 800 deg C is not so noticeable

  2. Chlorine Dioxide Gas Treatment of Cantaloupe and Residue Analysis

    OpenAIRE

    Kaur, Simran

    2013-01-01

    Chlorine dioxide is a selective oxidant and powerful antimicrobial agent. Previous work has shown that treatment of cantaloupe with chlorine dioxide gas at 5 mg/L for 10 minutes results in a 4.6 and 4.3 log reduction of E. coli O157:H7 and L. monocytogenes respectively. A significant reduction (p Current analytical methods for chlorine dioxide and chloroxyanions are only applicable to aqueous samples. Some of these methods have been used to determine surface residues in treated products by...

  3. Stability and effectiveness of chlorine disinfectants in water distribution systems.

    OpenAIRE

    Olivieri, V P; Snead, M C; Krusé, C W; Kawata, K.

    1986-01-01

    A test system for water distribution was used to evaluate the stability and effectiveness of three residual disinfectants--free chlorine, combined chlorine, and chlorine dioxide--when challenged with a sewage contaminant. The test distribution system consisted of the street main and internal plumbing for two barracks at Fort George G. Meade, MD. To the existing pipe network, 152 m (500 ft) of 13-mm (0.5 in.) copper pipe were added for sampling, and 60 m (200 ft) of 2.54-cm (1.0 in.) plastic p...

  4. INFRARED VIBRATIONAL SPECTRA OF CHLORINATED AND HYDROGENATED AMORPHOUS SILICON

    OpenAIRE

    Kalem, S; Chevallier, J.; Al Dallal, S.; Bourneix, J.

    1981-01-01

    The infrared spectra of chlorinated and hydrogenated amorphous silicon have been measured. In addition to the hydrogen induced bands at 2110, 1990, 885, 840 and 640 cm-1, we observe two new modes at 545 cm-1 (Si-Cl stretching) and 500 cm-1 ( Si TO modes induced by chlorine). Observation of the 545 cm-1 band proves that chlorine acts as a dangling bond terminator. Upon annealing, some of the Si-Cl groups transform into SiCl4 molecules (SiCl4 stretching at 615 cm-1). A good agreement is found b...

  5. AFFINITY OF THE ALLIGATOR ESTROGEN RECEPTOR FOR SERUM PESTICIDE CONTAMINANTS

    Science.gov (United States)

    Top predators, like the American alligator (Alligator mississippiensis) bioaccumulate and biomagnify persistent pollutants, such as organochlorine pesticides. In a recently published study, several pesticides and pesticide metabolites not previously reported in alligator eggs wer...

  6. A mobile App for military operational entomology pesticide applications

    Science.gov (United States)

    Multiple field studies conducted for the Deployed War Fighter Protection (DWFP) research program have generated over 80 specific guidance points for innovative combinations of pesticide application equipment, pesticide formulations, and application techniques for aerosol and residual pesticide treat...

  7. Comparison of Laboratory Experiments of Chemical, Biological, and Thermal Methods for Treatment of Chlorinated Solvent DNAPL at Kærgård Plantage in Denmark

    DEFF Research Database (Denmark)

    Christophersen, Mette; Christensen, Jørgen Fjeldsø; Jørgensen, Torben H.;

    2010-01-01

    in soil and groundwater, including sulfonamides, barbiturates, aniline, pyridine, chlorinated solvents (chloroethenes), fuel hydrocarbons, mercury, cyanide, lithium and many other compounds.  Wastes were disposed in six pits that continue to leach contaminants to groundwater. Contaminants in groundwater...... are estimated to discharge into the ocean at a rate of 20 m3/year, and public health concerns have prompted the closing of a 1.5 kilometer section of beach at the site. In 2008, the waste pits were excavated down to the water table, and the project is currently focused on evaluation of alternative in situ...... important design objective is to prevent or minimize mobilization of mercury and cyanide.      A series of bench tests have been performed to evaluate the feasibility of treating residual chlorinated solvent dense nonaqueous phase liquid (DNAPL) and other contaminants present in the saturated zone beneath...

  8. Pesticides: Benefaction or Pandora's Box? A synopsis of the environmental aspects of 243 pesticides

    NARCIS (Netherlands)

    Linders JBHJ; Jansma JW; Mensink BJWG; Otermann K; ACT

    1994-01-01

    The report provides an overview of physical, chemical and environmental data of 243 pesticides. The data mentioned are based on confidential information supplied by the manufacturers of the pesticides. For all pesticides mentioned a Final Environmental File, which is public, is derived. Tables with

  9. 75 FR 74673 - Pesticides; Regulation To Clarify Labeling of Pesticides for Export; Notification to the...

    Science.gov (United States)

    2010-12-01

    ... AGENCY 40 CFR Part 168 RIN 2070-AJ53 Pesticides; Regulation To Clarify Labeling of Pesticides for Export...(a) of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). As described in the Agency's... specificity to existing labeling regulations for the export of unregistered pesticide products and...

  10. 40 CFR 168.22 - Advertising of unregistered pesticides, unregistered uses of registered pesticides and FIFRA...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Advertising of unregistered pesticides, unregistered uses of registered pesticides and FIFRA section 24(c) registrations. 168.22 Section 168.22 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS STATEMENTS...

  11. Hydrocarbon Leak Detection Sensor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — FTT is proposing the development of a sensor to detect the presence of hydrocarbons in turbopump Inter-Propellant Seals (IPS). The purpose of the IPS is to prevent...

  12. Effect of the temperature and the chlorine pressure, over the aluminium chlorides obtained by direct chlorination of the 6061 alloy

    International Nuclear Information System (INIS)

    The aluminium chloride is synthesized by direct chlorination of aluminium, in agreement with the following reaction: Al(s) + 3/2 Cl2 AlCl3 (s,g).The present work focuses on the preparation of aluminium chlorides by two methods: (a) Chlorination of 6061 aluminium alloy with gaseous chlorine in sealed containers, filled with different pressures of gas, from 0.8 to 74 Kpa and in the range of temperature between 2000 and 5000C.(b) Chlorination of the same alloy in chlorine flow between 1500 and 4000C.In the sealed systems, the hexahydrated aluminium trichloride predominated over the anhydrous form. For pressures lower than 14 Kpa and temperatures under 2500C, the chloride didn't appear.The residues were rich in aluminium, chlorine and magnesium.In the other systems, the anhydrous chloride was found in the areas of the reactor of temperatures above 1000C, for all the thermal treatments. The waste was composed by CrCl3 and AlCl3.6H2O.The influence of the chlorine pressures and the heating temperature over the characteristics of the product, was studied.The characterization techniques were x-ray diffraction and energy dispersive spectroscopy, and the evolution of the structure was followed by scanning electron microscopy

  13. Mechanisms for formation, chlorination, dechlorination and destruction of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs)

    Energy Technology Data Exchange (ETDEWEB)

    Altarawneh, Mohammednoor; Dlugogorski, Bogdan Z.; Kennedy, Eric M.; Mackie, John C. [Process Safety and Environment Protection Research Group, School of Engineering, The University of Newcastle, Callaghan, NSW 2308 (Australia)

    2009-06-15

    understanding of the reaction mechanisms and suggests that further progress in the field needs to be facilitated by development of reliable mechanistic models for (1) catalytic pathways, (2) chlorination/dechlorination reactions including the Deacon reaction and the direct transfer of chlorine from solid surfaces into the aromatic moieties, and (3) formation of PCDD/Fs from precursors other than chlorophenols, especially pesticides. (author)

  14. Sorption of pesticides to aquifer minerals

    DEFF Research Database (Denmark)

    Clausen, Liselotte; Fabricius, Ida Lykke

    2000-01-01

    This paper summarizes results from a work were the sorption of five pesticides on seven minerals were studied in order to quantify the adsorption to different mineral surfaces. Investigated mineral phases are: quartz, calcite, kaolinite, a-alumina, and three iron oxides (2-line ferrihydrite......, goethite, lepidocrocite). Selected pesticides are: atrazine, isoproturon, mecoprop, 2,4-D, and bentazone. The results demonstrate that pesticides adsorb to pure mineral surfaces. However, the size of the adsorption depends on the type of pesticide and the type of mineral....

  15. Effect of Endocrine Disruptor Pesticides: A Review

    Directory of Open Access Journals (Sweden)

    Benoit Roig

    2011-06-01

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

  16. Effect of endocrine disruptor pesticides: a review.

    Science.gov (United States)

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

    2011-06-01

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

  17. Health Risk Assessment for Trace Metals, Polycyclic Aromatic Hydrocarbons and Trihalomethanes in Drinking Water of Cankiri, Turkey

    OpenAIRE

    Caylak, Emrah

    2012-01-01

    Lifetime exposure to trace metals, pesticides, polycyclic aromatic hydrocarbons (PAHs), trihalomethanes (THMs), and the other chemicals in drinking water through ingestion, and dermal contact may pose risks to human health. In this study, drinking water samples were collected from 50 sampling sites from Cankiri and its towns during 2010. The concentrations of all pollutants were analyzed, and then compared with permissible limits set by Turkish and WHO. For health risk assessment of trace met...

  18. HYDROCARBONS RESERVES IN VENEZUELA

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Cruz, D.J.

    2007-07-01

    Venezuela is an important player in the energy world, because of its hydrocarbons reserves. The process for calculating oil and associated gas reserves is described bearing in mind that 90% of the gas reserves of Venezuela are associated to oil. Likewise, an analysis is made of the oil reserves figures from 1975 to 2003. Reference is also made to inconsistencies found by international experts and the explanations offered in this respect by the Ministry of Energy and Petroleum (MENPET) and Petroleos de Venezuela (PDVSA) regarding the changes that took place in the 1980s. In turn, Hubbert's Law is explained to determine peak production of conventional oil that a reservoir or field will reach, as well as its relationship with remaining reserves. Emphasis is placed on the interest of the United Nations on this topic. The reserves of associated gas are presented along with their relationship with the different crude oils that are produced and with injected gas, as well as with respect to the possible changes that would take place in the latter if oil reserves are revised. Some recommendations are submitted so that the MENPET starts preparing the pertinent policies ruling reserves. (auth)

  19. Evaluation of hydrocarbon potential

    Energy Technology Data Exchange (ETDEWEB)

    Cashman, P.H.; Trexler, J.H. Jr. [Univ. of Nevada, Reno, NV (United States)

    1992-09-30

    Task 8 is responsible for assessing the hydrocarbon potential of the Yucca Mountain vincinity. Our main focus is source rock stratigraphy in the NTS area in southern Nevada. (In addition, Trexler continues to work on a parallel study of source rock stratigraphy in the oil-producing region of east central Nevada, but this work is not funded by Task 8.) As a supplement to the stratigraphic studies, we are studying the geometry and kinematics of deformation at NTS, particularly as these pertain to reconstructing Paleozoic stratigraphy and to predicting the nature of the Late Paleozoic rocks under Yucca Mountain. Our stratigraphic studies continue to support the interpretation that rocks mapped as the {open_quotes}Eleana Formation{close_quotes} are in fact parts of two different Mississippian units. We have made significant progress in determining the basin histories of both units. These place important constraints on regional paleogeographic and tectonic reconstructions. In addition to continued work on the Eleana, we plan to look at the overlying Tippipah Limestone. Preliminary TOC and maturation data indicate that this may be another potential source rock.

  20. Bioassay of polycyclic aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Van Kirk, E.A.

    1980-08-01

    A positive relationship was found between the photodynamic activity of 24 polycyclic aromatic hydrocarbons versus published results on the mutagenicity, carcinogenicity, and initiation of unscheduled DNA synthesis. Metabolic activation of benzo(a)pyrene resulted in detection of increased mutagenesis in Paramecium tetraurelia as found also in the Ames Salmonella assay. The utility of P. tetraurelia as a biological detector of hazardous polycyclic aromatic hydrocarbons is discussed.

  1. Aliphatic hydrocarbons of the fungi.

    Science.gov (United States)

    Weete, J. D.

    1972-01-01

    Review of studies of aliphatic hydrocarbons which have been recently detected in the spores of phytopathogenic fungi, and are found to be structurally very similar to the alkanes of higher plants. It appears that the hydrocarbon components of the few mycelial and yeast forms reported resemble the distribution found in bacteria. The occurence and distribution of these compounds in the fungi is discussed. Suggested functional roles of fungal spore alkanes are presented.

  2. PESTICIDE USE AND HUMAN HEALTH IN NORTHWESTERN JAMAICA

    OpenAIRE

    Ncube, Ngqabutho; Bessler, Patricia; Jolly, Pauline E; Tint, Kyaw; Fogo, Christopher; Binns, Alvin; Jolly, Curtis M.

    2007-01-01

    A number of studies have detected high levels of pesticide residues in surface water and aquatic life in Jamaica and acute pesticide poisoning is believed to be widespread there. Despite efforts by the Jamaican government to create awareness of the dangers of pesticides and adopt safe a pesticide disposal method, many farmers still display poor pesticide handling and disposal practices. The objectives of this study were to 1) describe pesticide use by farmers in northwestern Jamaica including...

  3. 40 CFR 158.2080 - Experimental use permit data requirements-biochemical pesticides.

    Science.gov (United States)

    2010-07-01

    ... requirements-biochemical pesticides. 158.2080 Section 158.2080 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2080 Experimental use permit data requirements—biochemical pesticides. (a) Sections...

  4. 40 CFR 158.2081 - Experimental use permit biochemical pesticides product chemistry data requirements table.

    Science.gov (United States)

    2010-07-01

    ... pesticides product chemistry data requirements table. 158.2081 Section 158.2081 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2081 Experimental use permit biochemical pesticides product chemistry data...

  5. 40 CFR 158.2173 - Experimental use permit microbial pesticides toxicology data requirements table.

    Science.gov (United States)

    2010-07-01

    ... pesticides toxicology data requirements table. 158.2173 Section 158.2173 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2173 Experimental use permit microbial pesticides toxicology data requirements table....

  6. 40 CFR 158.2174 - Experimental use permit microbial pesticides nontarget organisms and environmental fate data...

    Science.gov (United States)

    2010-07-01

    ... pesticides nontarget organisms and environmental fate data requirements table. 158.2174 Section 158.2174 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2174 Experimental use permit microbial pesticides...

  7. Insights into the Hydrocarbon Tolerance of Two Devosia Isolates, D. chinhatensis Strain IPL18T and D. geojensis Strain BD-c194T, via Whole-Genome Sequence Analysis

    OpenAIRE

    Hassan, Yousef I.; Lepp, Dion; Li, Xiu-Zhen; Zhou, Ting

    2015-01-01

    Hexachlorocyclohexane (HCH) was among the most commonly used pesticides after the Second World War. The extensive use of this hydrocarbon for almost six decades has created a contamination problem on a global scale, and bioremediation methods are being extensively explored. The reported ability of some Devosia species to grow in the presence of appreciable amounts of hydrocarbons (2,000 mg/kg of contaminated soil) is attracting closer attention. Here, we report the de novo genome assembly of ...

  8. Assessing the Impact of Chlorinated-Solvent Sites on Metropolitan Groundwater Resources

    OpenAIRE

    Brusseau, Mark L.; Narter, Matthew

    2013-01-01

    Chlorinated-solvent compounds are among the most common groundwater contaminants in the U.S.A. The majority of the many sites contaminated by chlorinated-solvent compounds are located in metropolitan areas, and most such areas have one or more chlorinated-solvent contaminated sites. Thus, contamination of groundwater by chlorinated-solvent compounds may pose a potential risk to the sustainability of potable water supplies for many metropolitan areas. The impact of chlorinated-solvent sites on...

  9. MULTISPECTRAL IDENTIFICATION OF CHLORINE DIOXIDE BYPRODUCTS IN DRINKING WATER

    Science.gov (United States)

    This paper discusses the identification of organic disinfectant byproducts (DNPS) at a pilot plant in Evansville, IN, that uses chlorine dioxide as a primary disinfectant. nconventional multispectral identification techniques (gas chromatography combined with high- and low-resolu...

  10. MICROEMULSION OF MIXED CHLORINATED SOLVENTS USING FOOD GRADE (EDIBLE) SURFACTANTS

    Science.gov (United States)

    Ground water contamination frequently consists of mixed chlorinated solvents [e.g., tetrachloroethylene (PCE), trichloroethylene (TCE), and trans-1,2- dichloroethylene (DCE)]. In this research, mixtures of the food grade (edible) surfactants bis(2-ethylhexyl) sodium sulfosuccinat...

  11. Modeling of residual chlorine in water distribution system

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Water quality within water distribution system may vary with both location and time. Water quality models are used to predict the spatial and temporal variation of water quality throughout water system. A model of residual chlorine decay in water pipe has been developed,given the consumption of chlorine in reactions with chemicals in bulk water, bio-films on pipe wall, in corrosion process, and the mass transport of chlorine from bulk water to pipe wall. Analytical methods of the flow path from water sources to the observed point and the water age of every observed node were proposed. Model is used to predict the decay of residual chlorine in an actual distribution system. Good agreement between calculated and measured values was obtained.

  12. In situ bioremediation of chlorinated solvent with natural gas

    International Nuclear Information System (INIS)

    A bioremediation system for the removal of chlorinated solvents from ground water and sediments is described. The system involves the the in-situ injection of natural gas (as a microbial nutrient) through an innovative configuration of horizontal wells

  13. The chlorination kinetics of zirconium dioxide mixed with carbon black

    International Nuclear Information System (INIS)

    In this research, the effects of chlorine gas at different chlorine partial pressures and carbon concentrations on the carbochlorination of zirconia were studied. It was found that in briquettes containing 18.7 %wt carbon, in a chlorine partial pressure range of 0.25-0.75 atm and for a reacted fraction of less than 0.7, the chemical reaction model was dominant for the carbochlorination process of zirconia. The order of reaction into chlorine gas (n) in this situation was 0.57. Moreover, the best weight ratio of carbon to zirconia was 40/60. In this case, the activation energy of the reaction was 209.9 kJ mol-1 in a temperature range of 1023-1223 K, and the dominant model was the chemical reaction model.

  14. Effect of Chlorine Dioxide Gas on Polymeric Packaging Materials

    Science.gov (United States)

    Permeability, solubility and diffusion coefficients of chlorine dioxide for high-density polyethylene (HDPE), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), polyvinyl chloride (PVC), polystyrene (PS), polyethylene terephthalate (PET), nylon, and multilayer of ethylene viny...

  15. Bioremediation of chlorinated ethenes in aquifer thermal energy storage

    NARCIS (Netherlands)

    Ni, Z.

    2015-01-01

      Subjects: bioremediation; biodegradation; environmental biotechnology, subsurface and groundwater contamination; biological processes; geochemistry; microbiology The combination of enhanced natural attenuation (ENA) of chlorinated volatile organic compounds (CVOCs) and aquife

  16. Determination of chlorine in graphite by combustion-ion chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Chen Lianzhong [Academia Sinica, Beijing, BJ (China). Inst. of Atomic Energy; Watanabe, Kazuo; Itoh, Mitsuo

    1995-09-01

    A combustion/ion chromatographic method has been studied for the sensitive determination of chlorine in graphite. A graphite sample was burnt at 900degC in a silica reaction tube at an oxygen flow rate of 200 ml/min. Chlorine evolved was absorbed in 20 ml of a 0.1 mM sodium carbonate solution. The solution was evaporated to dryness. The residue was dissolved with a small volume of water. Chlorine in the solution was determined using ion chromatography. The method was applied to JAERI graphite certified reference materials and practical graphite materials. The detection limit was about 0.8 {mu}gCl/g for a 2.0 g sample. The precision was about 2.5% (relative standard deviation) for samples with chlorine content of 70 {mu}g/g level. The method is also usable for coal samples. (author).

  17. Release of Chlorine and Sulfur during Biomass Torrefaction and Pyrolysis

    DEFF Research Database (Denmark)

    Saleh, Suriyati Binti; Flensborg, Julie Pauline; Shoulaifar, Tooran Khazraie;

    2014-01-01

    The release of chlorine (Cl) and sulfur (S) during biomass torrefaction and pyrolysis has been investigated via experiments in two laboratory-scale reactors: a rotating reactor and a fixed bed reactor. Six biomasses with different chemical compositions covering a wide range of ash content and ash......-forming elements were torrefied/pyrolyzed in the temperature range of 150-500 degrees C. The relative release of chlorine and sulfur was calculated based on mass balance and analysis of the biomass before and after torrefaction. In selected cases, measurement of methyl chloride (CH3Cl) in the gas from straw...... torrefaction has furthermore been conducted. The release of chlorine from straw was first observed at 250 degrees C and peaked with about 60-70% at 350 degrees C. Analysis of the released gas showed that most of the chlorine was released as methyl chloride. Increasing the straw content in the reactor resulted...

  18. ANAEROBIC AND AEROBIC TREATMENT OF CHLORINATED ALIPHATIC COMPOUNDS

    Science.gov (United States)

    Biological degradation of 12 chlorinated aliphatic compounds (CACs) was assessed in bench-top reactors and in serum bottle tests. Three continuously mixed daily batch-fed reactor systems were evaluated: anaerobic, aerobic, and sequential-anaerobic-aerobic (sequential). Glucose,...

  19. Complete Non-Radioactive Operability Tests for Cladding Hull Chlorination

    Energy Technology Data Exchange (ETDEWEB)

    Collins, Emory D [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Johnson, Jared A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hylton, Tom D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Brunson, Ronald Ray [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hunt, Rodney Dale [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); DelCul, Guillermo Daniel [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bradley, Eric Craig [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Spencer, Barry B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-04-01

    Non-radioactive operability tests were made to test the metal chlorination reactor and condenser and their accessories using batch chlorinations of non-radioactive cladding samples and to identify optimum operating practices and components that need further modifications prior to installation of the equipment into the hot cell for tests on actual used nuclear fuel (UNF) cladding. The operability tests included (1) modifications to provide the desired heating and reactor temperature profile; and (2) three batch chlorination tests using, respectively, 100, 250, and 500 g of cladding. During the batch chlorinations, metal corrosion of the equipment was assessed, pressurization of the gas inlet was examined and the best method for maintaining solid salt product transfer through the condenser was determined. Also, additional accessing equipment for collection of residual ash and positioning of the unit within the hot cell were identified, designed, and are being fabricated.

  20. Determination of chlorine in graphite by combustion-ion chromatography

    International Nuclear Information System (INIS)

    A combustion/ion chromatographic method has been studied for the sensitive determination of chlorine in graphite. A graphite sample was burnt at 900degC in a silica reaction tube at an oxygen flow rate of 200 ml/min. Chlorine evolved was absorbed in 20 ml of a 0.1 mM sodium carbonate solution. The solution was evaporated to dryness. The residue was dissolved with a small volume of water. Chlorine in the solution was determined using ion chromatography. The method was applied to JAERI graphite certified reference materials and practical graphite materials. The detection limit was about 0.8 μgCl/g for a 2.0 g sample. The precision was about 2.5% (relative standard deviation) for samples with chlorine content of 70 μg/g level. The method is also usable for coal samples. (author)

  1. MULTISPECTRAL IDENTIFICATION OF CHLORINE DIOXIDE DISINFECTION BYPRODUCTS IN DRINKING WATER

    Science.gov (United States)

    This paper discusses the identification of organic disinfection byproducts (DBPs) at a pilot plant in Evansville, IN, which uses chlorine dioxide as a primary disinfectant. Unconventional multispectral identification techniques (gas chromatography combined with high- and low reso...

  2. CHLORINE INACTIVATION OF CATEGORY "A" BIO-TERRORISM AGENTS

    Science.gov (United States)

    This poster presents information on the inactivation of select bioterrorist agents. Information will be presented on chlorine disinfection of vegetative cells of Brucella suis, Brucella melitensis, Burkholderia mallei, Burkholderia pseudomallei, Francisella tularensis and endos...

  3. Kinetics of Chlorine Decay in Water Distribution Systems

    Institute of Scientific and Technical Information of China (English)

    周建华; 薛罡; 赵洪宾; 汪永辉; 郭美芳

    2004-01-01

    A combined first and second-order model, which includes bulk decay and wall decay, was developed to describe chlorine decay in water distribution systems. In the model the bulk decay has complex relationships with total organic carbon (TOC), the initial chlorine concentration and the temperature. Except for the initial stages they can be simplified into a linear increase with TOC, a linear decrease with initial chlorine concentration and an exponential relationship with the temperature. The model also explains why chlorine decays rapidly in the initial stages. The parameters of model are determined by deriving the best fitness with experimental data. And the accuracy of model has been verified by using the experimental data and the monitoring data in a distribution system.

  4. SCENARIOS EVALUATION TOOL FOR CHLORINATED SOLVENT MNA

    Energy Technology Data Exchange (ETDEWEB)

    Vangelas, K; Brian02 Looney, B; Michael J. Truex; Charles J. Newell

    2006-08-16

    Over the past three decades, much progress has been made in the remediation of chlorinated solvents from the subsurface. Yet these pervasive contaminants continue to present a significant challenge to the U.S. Department of Energy (DOE), other federal agencies, and other public and private organizations. The physical and chemical properties of chlorinated solvents make it difficult to rapidly reach the low concentrations typically set as regulatory limits. These technical challenges often result in high costs and long remediation time frames. In 2003, the DOE through the Office of Environmental Management funded a science-based technical project that uses the U.S. Environmental Protection Agency's technical protocol (EPA, 1998) and directives (EPA, 1999) on Monitored Natural Attenuation (MNA) as the foundation on which to introduce supporting concepts and new scientific developments that will support remediation of chlorinated solvents based on natural attenuation processes. This project supports the direction in which many site owners want to move to complete the remediation of their site(s), that being to complete the active treatment portion of the remedial effort and transition into MNA. The overarching objective of the effort was to examine environmental remedies that are based on natural processes--remedies such as Monitored Natural Attenuation (MNA) or Enhanced Attenuation (EA). The research program did identify several specific opportunities for advances based on: (1) mass balance as the central framework for attenuation based remedies, (2) scientific advancements and achievements during the past ten years, (3) regulatory and policy development and real-world experience using MNA, and (4) exploration of various ideas for integrating attenuation remedies into a systematic set of ''combined remedies'' for contaminated sites. These opportunities are summarized herein and are addressed in more detail in referenced project documents and

  5. 酸碱气体对氯代芳烃削减的影响%Influence of acid and basic gases on the reduction of chlorinated aromatics

    Institute of Scientific and Technical Information of China (English)

    刘莎; 黄学敏; 黄林艳; 孙丽芳; 黎烈武; 刘烨煊; 苏贵金

    2014-01-01

    氯代芳烃多属于一种高毒性、难降解的持久性有机污染物,对环境和人类健康具有极大的危害。因此,削减其在环境的排放至关重要。在垃圾焚烧、化石燃料燃烧、铁矿石烧结等工业过程中,除存在氯代芳烃污染物外,还常伴有酸性气体二氧化硫、氮氧化物、氯化氢和碱性气体氨气的存在。这些气体物质的共存对氯代芳烃的削减具有重要的影响。本文综述了二氧化硫、氮氧化物、氯化氢和氨气等气体物质对氯代芳烃污染物在热催化过程和光降解过程中的降解、生成及阻滞的影响作用,阐述了其影响氯代芳烃削减和生成的机理,然后对研究过程中获得的成果和存在的问题进行了总结,并对气体污染物和氯代芳烃协同去除技术的研究方向进行了展望。%Chlorinated aromatic hydrocarbons, as a group of toxic, difficult to degrade and persistent organic pollutant, had significantly negative impacts on environment and human health. Therefore, it is vital to minimize their release in to the environment. During some industrial processes, such as, waste incineration, fossil fuel combustion and iron ore sintering, there exist acid gases such as sulfur dioxide, nitrogen oxides, hydrogen chloride, and also basic gases, such as ammonia, in addition to the unitentional release of chlorinated aromatic hydrocarbons. These coexisting gaseous substances could be expected to have significant impact on the release of chlorinated aromatics. This paper reviews the influence of sulfur dioxide, nitrogen oxides, hydrogen chloride and ammonia on the degradation, production, and inhibition of chlorinated aromatics in thermal catalytic and photodegradation processes, and disscussed mechanism. Further development of synergetic degradation of gas pollutants and chlorinated aromatic hydrocarbons is proposed.

  6. Characterization and source identification of hydrocarbons in water samples using multiple analytical techniques

    International Nuclear Information System (INIS)

    A study was conducted in which several analytical techniques were used to identify and characterize trace petroleum-related hydrocarbons and other volatile organic compounds in groundwater samples that were collected from a bedrock aquifer used for drinking water. A previous study had confirmed the presence of chlorinated compounds in the groundwater. The study presented in this paper was aimed at confirming the presence or absence of gasoline or other petroleum products in those samples. A service station was operated on this site for about 10 years and the adjacent property was owned by a chemicals handling company. Both operations were considered to be potentially responsible parties to the contamination of the aquifer. The difference in contaminants at different depths of the aquifer was examined using a variety of analytical techniques such as gas chromatography, mass spectrometry, flame-ionization detection, solid-phase-micro-extractor and head space. Chemical characterization results showed that the hydrocarbons found in the water samples near the surface were either gasoline or heavy petroleum products. The significant distribution of 5 target petroleum-characteristic alkylated polyaromatic hydrocarbon homologues and biomarkers confirmed the presence of another heavy petroleum product. The concentrations of the total petroleum hydrocarbon (TPH) and BTEX were found to be 1070 and 155 μg/kg of water for the samples near the surface. Results also showed that the deep groundwater samples collected at a depths ranging between 15 to 60 metres were also contaminated but to a much lesser degree. The concentrations of the TPH and BTEX were found to be only 130 and 2.6 μg/kg of water for the deep groundwater samples. The study also revealed that the groundwater was contaminated by a variety of volatile chlorinated compounds. 18 refs., 2 tabs., 7 figs

  7. Survival of Campylobacter jejuni in biofilms after chlorine treatment

    Directory of Open Access Journals (Sweden)

    Kunyaboon, S

    2006-09-01

    Full Text Available Survival of C. jejuni in biofilms isolated from two chicken houses in Thailand (FBRL-C04, FBRLB05 and FBRL-B06 after chlorine treatment was studied. Biofilm cultures were grown on stainless steel surface in 50% trypticase soy broth for 3 days, subsequently C. jejuni cells were allowed to attach to these biofilms for 4 h at 25ºC. Sodium hypochlorite was used to prepare sanitizing solution with active chlorine of 15 ppm and 25 ppm. Stainless steel coupons containing C. jejuni with and without biofilms were treated with chlorine for 30 sec and neutralized with 0.05% sodium thiosulfate. At both concentrations, C. jejuni were inactivated to lower than 1 log10CFU/cm2 when initial attachment load was approximately 4 log10CFU/cm2. However, C. jejuni in all samples treated with 15 ppm active chlorine were recovered in enrichment media. When treated with the higher concentration of chlorine, 25 ppm, C. jejuni in biofilm of FBRL-C04 (5/9, FBRL-B06 (1/9 and biofilm-free surface (1/9 could also be recovered. This indicates that chlorine treatment at 15 and 25 ppm could not completely inactivate C. jejuni attached to biofilms and biofilm-free surfaces. Biofilm of FBRL-C04 enhanced the survival of C. jejuni after chlorine treatment at 25 ppm although biofilm initial attachment as determined by plate count method was similar to that of other biofilms. Attachment load of viable biofilm cells may not contribute to enhanced survival of C. jejuni in chlorine treatment.

  8. Chlorine dioxide as an oxidant for organoboron compounds

    International Nuclear Information System (INIS)

    Practicability of using chlorine dioxide aqueous solution as an oxidant for terpene organoboron compounds prepared by hydroborating (+)α-pinene (1) and (-)β-pinene (2) is studied. By the methods of IR spectroscopy and 13C NMR it is shown that products of 1 and 2 oxidation are (-)-isopinocampheol and (-)-cis-myrtanol, which are formed with a high yield. In terms of its efficiency chlorine dioxide is no worse than hydrogen peroxide in reactions of organoboric compounds oxidation

  9. Bromoform production in tropical open-ocean waters: OTEC chlorination

    Energy Technology Data Exchange (ETDEWEB)

    Hartwig, E.O.; Valentine, R.

    1981-09-01

    The bromoform, and other volatile organics produced while chlorinating both the evaporator and condenser seawater during operation of the one megawatt (1 MW) OTEC-1 test facility are reported. Although many halogenated compounds might be produced as a result of chlorination, the quantitative analyses in this study focused on volatile EPA priority pollutants. Bromoform is the compound specifically recognized as a potential pollutant. Its concentration may be indicative of other halogenated species.

  10. Assessment of the risk of transporting liquid chlorine by rail

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, W.B.

    1980-03-01

    This report presents the risk of shipping liquid chlorine by rail. While chlorine is not an energy material, there are several benefits to studying chlorine transportation risks. First, chlorine, like energy materials, is widely used as a feedstock to industry. Second, it is the major purification agent in municipal water treatment systems and therefore, provides direct benefits to the public. Finally, other risk assessments have been completed for liquid chlorine shipments in the US and Europe, which provide a basis for comparison with this study. None of the previous PNL energy material risk assessments have had other studies for comparison. For these reasons, it was felt that a risk assessment of chlorine transportation by rail could provide information on chlorine risk levels, identify ways to reduce these risks and use previous studies on chlorine risks to assess the strengths and weaknesses of the PNL risk assessment methodology. The risk assessment methodology used in this study is summarized. The methodology is presented in the form of a risk assessment model which is constructed for ease of periodic updating of the data base so that the risk may be reevaluated as additional data become available. The report is sectioned to correspond to specific analysis steps identified in the model. The transport system and accident environment are described. The response of the transport system to accident environments is described. Release sequences are postulated and evaluated to determine both the likelihood and possible consequences of a release. Supportive data and analyses are given in the appendices. The risk assessment results are related to the year 1985 to allow a direct comparison with other reports in this series.

  11. Challenges in subsurface in situ remediation of chlorinated solvents

    OpenAIRE

    Broholm, Mette Martina; Fjordbøge, Annika Sidelmann; Christiansen, Camilla Maymann; Hønning, J.; B. H. Hansen; Nedergaard, L. W.; Kern, Kristina; Uthuppu, Basil; Jakobsen, Mogens Havsteen; Kjeldsen, Peter; Bjerg, Poul Løgstrup; Ottesen, L.

    2014-01-01

    Chlorinated solvent source zones in the subsurface pose a continuous threat to groundwater quality at many sites worldwide. In situ remediation of these sites is particularly challenging in heterogeneous fractured media and where the solvents are present as DNAPL. In situ remediation by chemical as well as biological degradation of chlorinated solvents is a contact sport and requires direct contact between the contaminant and the reactants and/or degrading microorganisms. In fractured geologi...

  12. Fate of free chlorine in drinking water during distribution in premise plumbing.

    Science.gov (United States)

    Zheng, Muzi; He, Chunguang; He, Qiang

    2015-12-01

    Free chlorine is a potent oxidizing agent and has been used extensively as a disinfectant in processes including water treatment. The presence of free chlorine residual is essential for the prevention of microbial regrowth in water distribution systems. However, excessive levels of free chlorine can cause adverse health effects. It is a major challenge to maintain appropriate levels of free chlorine residual in premise plumbing. As the first effort to assessing the fate of chlorine in premise plumbing using actual premise plumbing pipe sections, three piping materials frequently used in premise plumbing, i.e. copper, galvanized iron, and polyvinyl chloride (PVC), were investigated for their performance in maintaining free chlorine residual. Free chlorine decay was shown to follow first-order kinetics for all three pipe materials tested. The most rapid chlorine decay was observed in copper pipes, suggesting the need for higher chlorine dosage to maintain appropriate levels of free chlorine residual if copper piping is used. PVC pipes exhibited the least reactivity with free chlorine, indicative of the advantage of PVC as a premise plumbing material for maintaining free chlorine residual. The reactivity of copper piping with free chlorine was significantly hindered by the accumulation of pipe deposits. In contrast, the impact on chlorine decay by pipe deposits was not significant in galvanized iron and PVC pipes. Findings in this study are of great importance for the development of effective strategies for the control of free chlorine residual and prevention of microbiological contamination in premise plumbing.

  13. Fate of free chlorine in drinking water during distribution in premise plumbing.

    Science.gov (United States)

    Zheng, Muzi; He, Chunguang; He, Qiang

    2015-12-01

    Free chlorine is a potent oxidizing agent and has been used extensively as a disinfectant in processes including water treatment. The presence of free chlorine residual is essential for the prevention of microbial regrowth in water distribution systems. However, excessive levels of free chlorine can cause adverse health effects. It is a major challenge to maintain appropriate levels of free chlorine residual in premise plumbing. As the first effort to assessing the fate of chlorine in premise plumbing using actual premise plumbing pipe sections, three piping materials frequently used in premise plumbing, i.e. copper, galvanized iron, and polyvinyl chloride (PVC), were investigated for their performance in maintaining free chlorine residual. Free chlorine decay was shown to follow first-order kinetics for all three pipe materials tested. The most rapid chlorine decay was observed in copper pipes, suggesting the need for higher chlorine dosage to maintain appropriate levels of free chlorine residual if copper piping is used. PVC pipes exhibited the least reactivity with free chlorine, indicative of the advantage of PVC as a premise plumbing material for maintaining free chlorine residual. The reactivity of copper piping with free chlorine was significantly hindered by the accumulation of pipe deposits. In contrast, the impact on chlorine decay by pipe deposits was not significant in galvanized iron and PVC pipes. Findings in this study are of great importance for the development of effective strategies for the control of free chlorine residual and prevention of microbiological contamination in premise plumbing. PMID:26407709

  14. Disinfection of swine wastewater using chlorine, ultraviolet light and ozone.

    Science.gov (United States)

    Macauley, John J; Qiang, Zhimin; Adams, Craig D; Surampalli, Rao; Mormile, Melanie R

    2006-06-01

    Veterinary antibiotics are widely used at concentrated animal feeding operations (CAFOs) to prevent disease and promote growth of livestock. However, the majority of antibiotics are excreted from animals in urine, feces, and manure. Consequently, the lagoons used to store these wastes can act as reservoirs of antibiotics and antibiotic-resistant bacteria. There is currently no regulation or control of these systems to prevent the spread of these bacteria and their genes for antibiotic resistance into other environments. This study was conducted to determine the disinfection potential of chlorine, ultraviolet light and ozone against swine lagoon bacteria. Results indicate that a chlorine dose of 30 mg/L could achieve a 2.2-3.4 log bacteria reduction in lagoon samples. However, increasing the dose of chlorine did not significantly enhance the disinfection activity due to the presence of chlorine-resistant bacteria. The chlorine resistant bacteria were identified to be closely related to Bacillus subtilis and Bacillus licheniformis. A significant percentage of lagoon bacteria were not susceptible to the four selected antibiotics: chlortetracycline, lincomycin, sulfamethazine and tetracycline (TET). However, the presence of both chlorine and TET could inactivate all bacteria in one lagoon sample. The disinfection potential of UV irradiation and ozone was also examined. Ultraviolet light was an effective bacterial disinfectant, but was unlikely to be economically viable due to its high energy requirements. At an ozone dose of 100 mg/L, the bacteria inactivation efficiency could reach 3.3-3.9 log.

  15. Carboranyl-Chlorin e6 as a Potent Antimicrobial Photosensitizer.

    Directory of Open Access Journals (Sweden)

    Elena O Omarova

    Full Text Available Antimicrobial photodynamic inactivation is currently being widely considered as alternative to antibiotic chemotherapy of infective diseases, attracting much attention to design of novel effective photosensitizers. Carboranyl-chlorin-e6 (the conjugate of chlorin e6 with carborane, applied here for the first time for antimicrobial photodynamic inactivation, appeared to be much stronger than chlorin e6 against Gram-positive bacteria, such as Bacillus subtilis, Staphyllococcus aureus and Mycobacterium sp. Confocal fluorescence spectroscopy and membrane leakage experiments indicated that bacteria cell death upon photodynamic treatment with carboranyl-chlorin-e6 is caused by loss of cell membrane integrity. The enhanced photobactericidal activity was attributed to the increased accumulation of the conjugate by bacterial cells, as evaluated both by centrifugation and fluorescence correlation spectroscopy. Gram-negative bacteria were rather resistant to antimicrobial photodynamic inactivation mediated by carboranyl-chlorin-e6. Unlike chlorin e6, the conjugate showed higher (compared to the wild-type strain dark toxicity with Escherichia coli ΔtolC mutant, deficient in TolC-requiring multidrug efflux transporters.

  16. Effect of wastewater chlorination on endocrine disruptor removal.

    Science.gov (United States)

    Noutsopoulos, C; Mamais, D; Samaras, V; Bouras, T; Marneri, M; Antoniou, K

    2013-01-01

    Endocrine disrupting chemicals (EDCs) are compounds of mainly anthropogenic origin that interfere with the endocrine system of animals and humans thus causing a series of disorders. Wastewater treatment plants are one of the major routes for transporting such chemicals to the water courses. In the context of this study, several chlorination batch tests were performed in order to assess the effectiveness of chlorination to remove bisphenol A (BPA), triclosan (TCS), nonylphenol (NP) and its ethoxylates (NP1EO and NP2EO) from secondary effluent. According to the results, an appreciable removal of NP, BPA and TCS to the order of 60-84% was observed as an effect of moderate chlorination doses. This was not the case for NP1EO and NP2EO as even at high chlorine doses, removal efficiencies were lower (37% for NP1EO and 52% for NP2EO). Removal efficiencies of NP, BPA and TCS are practically independent of contact time, although this was not the case for NP1EO and NP2EO. Based on toxicity experiments, it is anticipated that following chlorination of the target chemicals, production of more toxic metabolites is taking place. Therefore the effectiveness of chlorination to remove EDCs is questionable and more research is needed to guarantee safe wastewater reuse. PMID:23552244

  17. Prompt gamma analysis of chlorine in concrete for corrosion study.

    Science.gov (United States)

    Naqvi, A A; Nagadi, M M; Al-Amoudi, O S B

    2006-02-01

    Measurement of chlorine in concrete is very important for studying of corrosion of reinforcing steel in concrete. Corrosion of reinforcing steel is primarily ascribed to the penetration of chloride ions to the steel surface. Preventive measures for avoiding concrete structure reinforcement corrosion requires monitoring the chloride ion concentration in concrete so that its concentration does not exceed a threshold limit to initiate reinforcement concrete corrosion. An accelerator based prompt gamma neutron activation analysis (PGNAA) setup has been developed for non-destructive analysis of elemental composition of concrete samples. The setup has been used to measure chlorine concentration in concrete samples over a 1-3 wt% concentration range. Although a strong interference has been observed between the chlorine gamma-rays and calcium gamma-rays from concrete, the chlorine concentration in concrete samples has been successfully measured using the 1.164 and 7.643 MeV chlorine gamma-rays. The experimental data were compared with the results of the Monte Carlo simulations. An excellent agreement has been achieved between the experimental data and results of Monte Carlo simulations. The study has demonstrated the successful use of the accelerator-based PGNAA setup in non-destructive analysis of chlorine in concrete samples. PMID:16129605

  18. Pesticide poisoning in the developing world--a minimum pesticides list

    DEFF Research Database (Denmark)

    Eddleston, Michael; Karalliedde, Lakshman; Buckley, Nick;

    2002-01-01

    In parts of the developing world, pesticide poisoning causes more deaths than infectious diseases. Use of pesticides is poorly regulated and often dangerous; their easy availability also makes them a popular method of self-harm. In 1985, the UN Food and Agriculture Organisation (FAO) produced...... a voluntary code of conduct for the pesticide industry in an attempt to limit the harmful effects of pesticides. Unfortunately, a lack of adequate government resources in the developing world makes this code ineffective, and thousands of deaths continue today. WHO has recommended that access to highly toxic...... pesticides be restricted--where this has been done, suicide rates have fallen. Since an Essential Drugs List was established in 1977, use of a few essential drugs has rationalised drug use in many regions. An analogous Minimum Pesticides List would identify a restricted number of less dangerous pesticides...

  19. Pattern of pesticide storage before pesticide self-poisoning in rural Sri Lanka

    DEFF Research Database (Denmark)

    Mohamed, Fahim; Manuweera, Gamini; Gunnell, David;

    2009-01-01

    BACKGROUND: Deliberate self-poisoning with agricultural pesticides is the commonest means of suicide in rural Asia. It is mostly impulsive and facilitated by easy access to pesticides. The aim of this large observational study was to investigate the immediate source of pesticides used for self-harm...... the particular pesticide for self-harm were its easy accessibility (n = 311, 46%) or its popularity as a suicide agent in their village (n = 290, 43%). CONCLUSION: Three quarters of people who ingested pesticides in acts of self-harm used products that were available within the home or in close proximity......; relatively few patients purchased the pesticide for the act. The study highlights the importance of reducing the accessibility of toxic pesticides in the domestic environment....

  20. Site-selective photofragmentation of chlorinated polymeric films observed around the chlorine K-edge

    Energy Technology Data Exchange (ETDEWEB)

    Arantes, C., E-mail: csilva@inmetro.gov.br [Divisão de Metrologia de Materiais, Instituto Nacional de Metrologia, Qualidade e Tecnologia, Xerém 25250-020, Duque de Caxias, RJ (Brazil); Mendes, L.A.V. [Instituto de Física, Universidade Federal da Bahia, Ondina, 40210-340 Salvador, BA (Brazil); Pinho, R.R. [Departamento de Física-ICE, Universidade Federal de Juiz de Fora, Campus Universitário, 36036-330 Juiz de Fora, MG (Brazil); Ferreira, M. [PEMM/COPPE, Universidade Federal do Rio de Janeiro, Cidade Universitária, Ilha do Fundão, 21941-972 Rio de Janeiro, RJ (Brazil); Souza, G.G.B. de; Rocha, A.B.; Rocco, M.L.M. [Instituto de Química, Universidade Federal do Rio de Janeiro, Cidade Universitária, Ilha do Fundão, 21941-909 Rio de Janeiro, RJ (Brazil)

    2013-03-29

    Highlights: ► PVC and PVDC were studied by PSID and NEXAFS techniques at the Chlorine 1s-edge. ► PVC film presented isotope ratio of 3:1 in the PSID spectrum. ► Cl{sup +} ion yield curves reproduce the photoabsorption spectrum for both polymers. ► Site-selectivity of C–Cl bond breaking due to an efficient spectator Auger decay. - Abstract: Photon stimulated ion desorption (PSID) and Near-edge X-ray absorption fine structure (NEXAFS) studies have been performed on poly(vinyl chloride) (PVC) and poly(vinyl dichloride) (PVDC) around the chlorine 1s-edge. Experiments were performed using a synchrotron source operating in the single-bunch mode and a time-of-flight mass spectrometry for ion analysis. Cl{sup +} ion yields, as a function of the photon energy, reproduce the photoabsorption spectrum, showing significant increase at the 1s-resonance. Edge-jump ratios, defined as the ratio between edge-jumps (intensity ratio of the yields between above and below the absorption edge) of two different transitions, for Cl{sup +} ion yields were much higher than the equivalent electron yields, indicating site-selectivity in C–Cl bond breaking for both polymers, as a result of efficient spectator Auger decay. The expected isotope ratio of 3:1 for chlorine was measured for PVC. The interpretation of the NEXAFS spectrum was assisted by quantum mechanical calculations at a multireference perturbation theory level.