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Sample records for chlorinated hydrocarbon residues

  1. Chlorinated hydrocarbon and mercury residues in woodcock in the United States, 1970-71

    USGS Publications Warehouse

    Clark, D.R., Jr.; McLane, M.A.R.

    1974-01-01

    During Late 1970 and early 1971, 229 woodcock (Philohela minor) were collected from 23 Eastern and Midwestern States. Analyses for chlorinated hydrocarbons and mercury in these migratory birds showed generally low levels which are not considered dangerous to human consumers. In this survey, Louisiana woodcock had lower residues of heptachlor epoxide and DDE than those tested in a 1965 survey. PCB levels, however, may have increased. Mirex levels were greatest in Mississipi and Louisiana woodcock. Pooling of birds and averaging of individually analyzed birds did not provide equivalent estimates of equivalent residues; pool values tended to be larger and more variable. Levels of six chlorinated hydrocarbons and mercury were negatively correlated with the latitude of the collection site. However, this relationship seemed weakest for PCB's. Among eight chemical residues, PCB levels were most often correlated with levels of the other seven. Levels of chlorinated hydrocarbons in wings were correlated with levels in breast muscle and in carcass; however, mean levels of certain residues differed significantly among wing, muscle, and carcass even when compared on a lipid basis.

  2. Chlorinated hydrocarbon residues in Baikal seal (Phoca sibirica) from Lake Baikal: Levels, patterns, and metabolism

    SciTech Connect

    Nakata, H.; Tanabe, S.; Tatsukawa, R.; Amano, M.; Miyazaki, N.; Petrov, A.

    1995-12-31

    Contamination of chlorinated hydrocarbons such as DDTs (DDT and its metabolites), PCBs (polychlorinated biphenyls), CHLs (chlordane compounds) and HCHs (hexachlorocyclohexanes) was assessed in the blubber of Baikal seal (Phoca sibirica) and their fish diet collected from Lake Baikal in 1992. Higher concentrations of DDTs and PCBs were detected, ranging from 4.9 to 160 {micro}g/g and 3.5 to 64 {micro}g/g on a lipid weight basis, respectively, whereas levels of CHLs and HCHs were approximately one or three orders of magnitude lower than those of DDTs and PCBs. The average of DDTs concentrations in adult male Baikal seals were about an order of magnitude higher than those reported for seals in the North Sea around UK and comparable to grey seal in the Baltic Sea, indicating that Baikal seals are categorized in a highly contaminated group. A positive age dependent accumulation of DDTs, PCBs and CHLs was found in male, while a steady-state was observed in female which attributes to the reproductive transfer, mainly lactation, of these chemicals. On the basis of contaminant burdens in adult seals, it was estimated that adult females transfer about 19% and 14% of their DDT and PCB body burdens to their pups during a reproductive process. Based on the data from isomer specific analysis of PCBs, it can be suggested that Baikal seals have higher capacity to metabolize congeners with vicinal H-atoms in meta, para positions than those of marine mammals.

  3. Process for Photochemical Chlorination of Hydrocarbons

    DOEpatents

    Beanblossom, W S

    1951-08-28

    A process for chlorination of a major portion of the hydrogen atoms of paraffinic hydrocarbons of five or more carbon atoms may be replaced by subjecting the hydrocarbon to the action of chlorine under active light. The initial chlorination is begun at 25 to 30 deg C with the chlorine diluted with HCl. The later stages may be carried out with undiluted chlorine and the temperature gradually raised to about 129 deg C.

  4. Chlorinated hydrocarbons in peat

    SciTech Connect

    Rapaport, R.A.

    1985-01-01

    Concentrations (ng/g), accumulation rates (ug/m/sup 2/=yr) and burdens were determined for DDT (1,1,1-trichlorophenyl2-2'bis(p-chlorophenyl)ethane), polychlorinated biphenyls. Toxaphene, hexachlorobenzene (HCB) and a,b,g-hexachlorocyclohexanes (HCHs) in peat cores taken across the mid-latitudes of North America. Because peat bogs are ombrotrophic, thereby receiving all contaminant inputs from the atmosphere and because peat cores were dated, atmospheric input functions were constructed for all of the compounds listed above excepting the HCHs. Compound inventories (burdens) in peat cores of PCBs, HCB, HCHs, Toxaphene, DDT, Pb and Zn were compared, indicating a strong influence from areas proximate to industrial sources and the atmospheric transport from source regions. Untransformed parent DDT (p,p' and o,p'-DDT) in surface peat and in precipitation provides evidence for the long range transport of DDT from neighboring countries where use has increased over the past 10-15 years. Present accumulation rates of DDT in peat are about 10-20% of maximum levels associated with peak use in the US around 1960. The DDT input function that was developed can be used to date peat cores. Transformations of DDT and PCBs were also examined in peat cores. First order transformation rates of DDT (p,p' and o,p') to DDD in anaerobic peat core environments ranged from 0.03 to 0.09 yr/sup -1/ with differences related to temperature. Aerobic transformation of PCB congeners in peat cores and microcosms was rapid for 2,3 and several 4 chlorinated congeners (T/sub 1/2 less than or equal to 0.2 to 3 years) and declined with increasing chlorine number.

  5. Chemistry of combined residual chlorination

    SciTech Connect

    Leao, S.F.; Selleck, R.E.

    1982-01-01

    The decay of the combined chlorine residual was investigated in this work. Recent concerns about the formation of undesirable compounds such as chloroform with free residual chlorination have focused attention on the alternative use of combined residual chlorination. This work investigates the applicability of reactions proposed to describe the transformations and decay of the combined residual with time. Sodium hypochlorite was added to buffered solutions of ammonia with the chlorine residual being monitored over periods extending up to 10 days. The reaction was studied at four initial concentrations of hypochlorite of 100, 50, 25 and 10 mg/L as Cl/sub 2/ with molar application ratios of chlorine to ammonia, defined herein as M ratios, of 0.90, 0.50, 0.25 and 0.05 at each hypochlorite dose. Sixty-eight experiments were conducted at the pH of 6.6 and 7.2. The conclusions are: (1) in the absence of free chlorine, the concentration of NH/sub 3/ does not seem to affect the rate of disappearance of the residual other than through the formation of NHCl/sub 2/ by NH/sub 2/Cl hydrolysis; (2) the reaction between NHCl/sub 2/ and NH/sub 4//sup +/ to form NH/sub 2/Cl is either much slower than reported by Gray et. al. or the mechanism is different with a rate limiting step not involving NH/sub 3/ or NH/sub 4//sup +/; (3) a redox reaction in addition to the first-order decomposition of NHCl/sub 2/ appears necessary. Model simulation results indicated that a reaction of the type NH/sub 2/Cl + NHCl/sub 2/ ..-->.. P added to the first-order NHCl/sub 2/ decomposition can explain the results observed except at the higher chlorine doses.

  6. BOOSTER CHLORINATION FOR MANAGING DISINFECTANT RESIDUALS

    EPA Science Inventory

    Booster chlorination is an approach to residual maintenance in which chlorine is applied at strategic locations within the distribution system. Situations in which booster chlorination may be most effective for maintaining a residual are explained informally in the context of a ...

  7. RELATIONSHIPS BETWEEN LABORATORY AND PILOT-SCALE COMBUSTION OF SOME CHLORINATED HYDROCARBONS

    EPA Science Inventory

    Factors governing the occurence of trace amounts of residual organic substance emmissions (ROSEs) in full-scale incierators are not fully understood. Pilot-scale spray combustion expereiments involving some liquid chlorinated hydrocarbons (CHCs) and their dilute mixtures with hy...

  8. Behavioral toxicology, risk assessment, and chlorinated hydrocarbons.

    PubMed Central

    Evangelista de Duffard, A M; Duffard, R

    1996-01-01

    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 changes 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. PMID:9182042

  9. PRODUCTION OF CHLORINE ATOMS FROM THE REACTION OF OH WITH CHLORINATED HYDROCARBONS

    EPA Science Inventory

    Measurements from previous studies have shown that when hydroxyl radicals react with various chlorinated hydrocarbons under atmospheric conditions, free chlorine atoms can be produced. hetechnique described in this study involves scavenging Cl atoms produced by the reaction (usin...

  10. Stable isotope investigations of chlorinated aliphatic hydrocarbons.

    SciTech Connect

    Abrajano, T.; Heraty, L. J.; Holt, B. D.; Huang, L.; Sturchio, N. C.

    1999-06-01

    Stable isotope ratio measurements for carbon (C) and chlorine (Cl) can be used to elucidate the processes affecting transformation and transportation of chlorinated aliphatic hydrocarbons (CAHs) in the environment. Methods recently developed in our laboratory for isotopic analysis of CAHs have been applied to laboratory measurements of the kinetic isotope effects associated with aerobic degradation of dichloromethane (DCM) and with both anaerobic and aerobic cometabolic degradation of trichlomethene (TCE) in batch and column microbial cultures. These experimental determinations of fractionation factors are crucial for understanding the behavior of CAHs in complex natural systems, where the extent of biotransformation can be masked by dispersion and volatilization. We have also performed laboratory investigations of kinetic isotope effects accompanying evaporation of CAHs, as well as field investigations of natural attenuation and in situ remediation of CAHs in a number of contaminated shallow aquifers at sites operated by the federal government and the private sector.

  11. Hydrocarbon and chlorinated hydrocarbon-soluble magnesium dialkoxides

    SciTech Connect

    Kamienski, C.W.

    1988-05-31

    This patent describes a process for the preparation of hydrocarbon or chlorinated hydrocarbon solvent solutions of magnesium dialkoxides, which comprises reacting a suspension of magnesium metal or magnesium amide, or a solution of a dialkyimagnesium compound, in a volatile hydrocarbon or chlorinated hydrocarbon solvent with an alcohol selected from the group of (a) aliphatic, cycloaliphatic and acyclic C/sub 5/-C/sub 18/ beta- and gamma-alkyl-substituted secondary and tertiary monohydric alcohols; or (b) mixtures of the (a) alcohols with C/sub 3/-C/sub 18/ aliphatic or cycloaliphatic beta- and gamma-alkyl-unsubstituted secondary or tertiary alcohols; or (c) mixtures of the (a) alcohols with C/sub 1/-C/sub 18/ aliphatic primary unsubstituted and 2-alkyl-substituted alcohols; the mole ratios of the (a) to the (b), and the (a) to the (c), alcohols being 1 of the (a) alcohols to 0.1 to 2 of the (b) and/or the (c) alcohols.

  12. Biological monitoring of chlorinated hydrocarbon solvents

    SciTech Connect

    Monster, A.C.

    1986-08-01

    The possibility of biological monitoring of exposure to some volatile, halogenated hydrocarbons will be discussed. Most of these agents are widely used as solvents. All agents act on the nervous system as narcotics and differ widely in toxicity. Most of the solvents undergo biotransformation to metabolites. This allows biological assessment of exposure by measurement of the solvent and/or metabolites in exhaled air, blood, and/or urine. However, the same metabolites may occur with exposure to different chlorinated hydrocarbons, eg, trichloroethanol and trichloroacetic acid from exposure to trichloroethene, tetrachloroethene, and 1,1,1-trichloroethane. On the other hand, these agents differ widely in the percentage that is metabolized. There are large gaps in our knowledge, however, and much research will have to be carried out before even tentative data can be established for most of the solvents.

  13. ENZYME-BASED DETECTION OF CHLORINATED HYDROCARBONS IN WATER

    EPA Science Inventory

    An enzyme-based approach for detecting hazardous levels of high molecular weight chlorinated hydrocarbons in natural waters has been explored. An extensive review of the literature indicated that the enzymes, lactate dehydrogenase, carbonic anhydrase, hexokinase, phosphorylase an...

  14. Chlorinated hydrocarbons and eggshell changes in raptorial and fish-eating birds

    USGS Publications Warehouse

    Hickey, J.J.; Anderson, D.W.

    1968-01-01

    Catastrophic declines of three raptorial species in the United States have been accompanied by decreases in eggshell thickness that began in 1947, have amounted to 19 percent or more, and were identical to phenomena reported in Britain. In 1967, shell thickness in herring gull eggs from five states decreased with increases in chlorinated hydrocarbon residues.

  15. Chlorinated hydrocarbons in lichen and moss samples from the Antarctic Peninsula

    SciTech Connect

    Bacci, E.; Calamari, D.; Gaggi, C.; Fanelli, R.; Focardi, S.; Morosini, M.

    1986-01-01

    The concentrations of some chlorinated hydrocarbon residues (HCB, HCH isomers, p,p'DDT and DDE, PCB cogeners) in lichen and moss samples from the Antarctic Peninsula are reported and compared with available data from other parts of the world. The use of these materials as indicators of tropospheric contamination levels in Antarctica is discussed.

  16. In-situ demonstration of radio-frequency enhanced chlorinated hydrocarbon remediation

    SciTech Connect

    Kasevich, R.S.; Price, S.L.; Faust, D.L.; Jarosch, T.R.

    1994-06-01

    This paper discusses the results of a successful demonstration of radio frequency (RF) heating for enhanced chlorinated hydrocarbon remediation at the M-Area Seepage Basin of the Department of Energy`s Savannah River Site. RF heating was integrated with soil vapor extraction (SVE) to enhance the release of residual volatile chlorinated hydrocarbons which are concentrated in low permeable clay lenses in the unsaturated zone. Participants in this effort consisted of the Westinghouse Savannah River Technology Center; the Westinghouse Science and Technology Center (Pittsburgh, PA); and KAI Technologies, Inc. which provided the RF technology. Additionally, a better understanding of RF heating technology is gained through a description of the RF heating system.

  17. PCB's and chlorinated hydrocarbon pesticides in Antarctic atmosphere and hydrosphere

    SciTech Connect

    Tanabe, S.; Hidaka, H.; Tatsukawa, R.

    1983-01-01

    PCBs and chlorinated hydrocarbon pesticides such as DDTs and HCHs (BHCs) were measured in air, water, ice and snow samples collected around the Japanese research stations in Antarctica and adjacent oceans during December 1980 to March 1982. The atmospheric concentrations of chlorinated hydrocarbons decreased in the transport process from northern lands to Antarctica, but the compositions of PCBs, DDT compounds and HCH isomers were relatively uniform throughout this process. Regional and seasonal variations were found in aerial concentrations of these pollutants at Syowa Station and adjacent seas in Antarctica. Chlorinated hydrocarbons were also detected in snow, ice, lake water and sea water samples, in which rather high concentrations were found in snow and ice samples. This suggests that snow and ice serve as media of supply of these pollutants into Antarctic marine environment.

  18. Persistence of chlorinated hydrocarbon contamination in a California marine ecosystem

    SciTech Connect

    Young, D.R.; Gossett, R.W.; Heesen, T.C.

    1989-01-01

    Despite major reductions in the dominant DDT and polychlorinated biphenyls (PCB) input off Los Angeles (California, U.S.A.) in the early 1970s, the levels of these pollutants decreased only slightly from 1972 to 1975 both in surficial bottom sediments and in a flatfish bioindicator (Dover sole, Microstomus pacificus) collected near the submarine outfall. Concentrations of these pollutants in the soft tissues of the mussel Mytilus californianus, collected intertidally well inshore of the highly contaminated bottom sediments, followed much more closely the decreases in the outfall discharges. These observations suggest that contaminated sediments on the seafloor were the principal (although not necessarily direct) cause of the relatively high and persistent concentrations of DDT and PCB residues in tissues. The study indicated that residues of the higher-molecular-weight chlorinated hydrocarbons, such as DDT and PCB, can be highly persistent once released to coastal marine ecosystems and that their accumulation in surficial bottom sediments is the most likely cause of this persistence observed in the biota of the discharge zone.

  19. Influence of humic substances on the formation of chlorinated polycyclic aromatic hydrocarbons during chlorination of polycyclic aromatic hydrocarbon polluted water

    SciTech Connect

    Johnsen, S.; Gribbestad, I.S.

    1988-08-01

    Chlorinated polycyclic aromatic hydrocarbons (PAH) are present at nanogram per liter levels in lake water. Some of these compounds are known to be mutagenic in the Ames Salmonella test. The PAH compounds fluorene, anthracene, fluoranthene, and benzo(a)pyrene were dissolved in lake water with low humus content and in humus water with 9.17 mg of total organic carbon/L, followed by sodium hypochlorite chlorination at different concentrations. Reaction of PAH and formation of chlorinated PAH were measured by cyclohexane extraction of the samples 3 days after chlorination and gas chromatography/mass spectrometry analyses of the extracts. The PAH-chlorine reaction was found to be dependent upon the concentration of free active chlorine in the water, and the presence of humic substances was found to affect the formation of chlorinated PAH. Chlorinated PAH were formed in the lake water samples of fluoranthene and benzo(a)pyrene, but no chlorinated PAH were detected in the presence of humic substances.

  20. Shock-tube pyrolysis of chlorinated hydrocarbons - Formation of soot

    NASA Technical Reports Server (NTRS)

    Frenklach, M.; Hsu, J. P.; Miller, D. L.; Matula, R. A.

    1986-01-01

    Soot formation in pyrolysis of chlorinated methanes, their mixtures with methane, and chlorinated ethylenes were studied behind reflected shock waves by monitoring the attenuation of an He-Ne laser beam. An additional single-pulse shock-tube study was conducted for the pyrolysis of methane, methyl chloride, and dichloromethane. The experiments were performed at temperatures 1300-3000 K, pressures of 0.4-3.6 bar, and total carbon atom concentrations of 1-5 x 10 to the 17th atoms cu cm. The amounts of soot produced in the pyrolysis of chlorinated hydrocarbons are larger than that of their nonchlorinated counterparts. The sooting behavior and product distribution can be generally explained in terms of chlorine-catalyzed chemical reaction mechanisms. The pathway to soot from chlorinated methanes and ethylenes with high H:Cl ratio proceeds via the formation of C2H, C2H2, and C2H3 species. For chlorinated hydrocarbons with low H:Cl ratio, the formation of C2 and its contribution to soot formation at high temperatures becomes significant. There is evidence for the importance of CHCl radical and its reactions in the pyrolysis of dichloromethane.

  1. USE OF SONOCHEMISTRY IN MONITORING CHLORINATED HYDROCARBONS IN WATER

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has been examining the potential of combining sonication with available measurement technologies for monitoring chlorinated hydrocarbons in water. The chloride ion (C1-) concentration, conductivity, and pH were measured before and af...

  2. Transformation of Chlorinated Hydrocarbons on Synthetic Green Rusts

    EPA Science Inventory

    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...

  3. TURBULENT FLAME REACTOR STUDIES OF CHLORINATED HYDROCARBON DESTRUCTION EFFICIENCY

    EPA Science Inventory

    Four mixtures of C1 and C2 chlorinated hydrocarbons, diluted in heptane, were burned in a Turbulent Flame Reactor (TFR) under high and low oxygen conditions. Emissions of undestroyed feed, stable organic by-products, carbon monoxide, carbon dioxide and oxyg...

  4. MICROEMULSION FORMATION WITH MIXED CHLORINATED HYDROCARBON LIQUIDS

    EPA Science Inventory

    Mixing rules for water/chlorocarbon/anionic-surfactant systems have been studied. t was found that the behavior of chlorocarbons parallels the ideal mixing rules for hydrocarbons. he polarity of some chlorocarbons prevented a direct determination of electrolyte concentration and ...

  5. Minnows can acclimate to total residual chlorine

    SciTech Connect

    Lotts, J.W. Jr.; Stewart, A.J.

    1995-08-01

    Observations in a chlorine-contaminated stream in eastern Tennessee revealed several species of fish in areas where total residual chlorine (TRC) concentrations were often great enough to be lethal, based on the results of other studies. The authors used in situ and laboratory experiments to test the hypothesis that minnows could acclimate to TRC. Acclimation was assessed by time-to-death for fish exposed to a single lethal regime of TRC. In in situ experiments, striped shiner and central stoneroller minnows collected from East Fork Poplar Creek at a TRC-contaminated site and a site farther downstream, where TRC was below detection, were caged at sites in the stream where TRC concentrations were either nil or great enough to be lethal. At the cage with high TRC, minnows collected from the ``TRC-free`` site survived two to four times longer (15.8 h vs. 6.1 h) than the same species from the ``TRC-free`` site. In laboratory experiments, golden shiner minnows were exposed to TRC in a stepwise increasing concentration regime (0.04 mg/L during week 1, 0.08 mg/L during week 2, and 0.12 mg/L during week 3) before being challenged-tested with a lethal concentration of TRC. Minnows that had been previously exposed to TRC survived longer than controls in each test, and the magnitude of the mean time to death increased as the TRC concentration and duration of exposure increased (1.2-, 2.5-, and 3.9-fold increases for weeks 1, 2, and 3, respectively). Another experiment with golden shiner minnows showed that a 21-d exposure to TRC at a low concentration (0.04 mg/L) only slightly increased their tolerance to TRC. Thus, several minnow species apparently can acclimate, fairly rapidly, to TRC. This study may help explain why fish kills are less common than expected in TRC-contaminated streams.

  6. SOURCE RECEPTOR METHODOLOGY FOR SOME CHLORINATED HYDROCARBONS

    EPA Science Inventory

    A source-receptor methodology is described that can be used to estimate emission rates of halogenated hydrocarbons from a manufacturing plant when access to the plant is not possible. An inert tracer is released at a known rate from a vehicle traveling back and forth on a road ou...

  7. Estimating The Thermodynamics And Kinetics Of Chlorinated Hydrocarbon Degradation

    SciTech Connect

    Bylaska, Eric J.

    2006-08-01

    Many different degradation reactions of chlorinated hydrocarbons are possible in natural ground waters. In order to identify which degradation reactions are important, a large number of possible reaction pathways must be sorted out. Recent advances in ab initio electronic structure methods have the potential to help identify relevant environmental degradation reactions by characterizing the thermodynamic properties of all relevant contaminant species and intermediates for which experimental data is usually not available, as well as provide activation energies for relevant pathways. In this paper, strategies based on ab initio electronic structure methods for estimating thermochemical and kinetic properties of reactions with chlorinated hydrocarbons are presented. Particular emphasis is placed on strategies that are computationally fast and can be used for large organochlorine compounds such as 4,4?-DDT.

  8. Process for treating liquid chlorinated hydrocarbon wastes containing iron

    SciTech Connect

    Doane, E.P.

    1986-09-30

    A process is described for reducing the ferric chloride content of liquid waste streams comprising higher boiling chlorinated hydrocarbons and containing amounts of ferric chloride. The process consists essentially of contacting the waste stream with an amount of water sufficient to convert ferric chloride contained in the stream to solid ferric chloride hexahydrate, and then removing the solid hexahydrate by filtration or centrifugation from the waste stream.

  9. Aerobic microorganism for the degradation of chlorinated aliphatic hydrocarbons

    DOEpatents

    Fliermans, Carl B.

    1989-01-01

    A chlorinated aliphatic hydrocarbon-degrading microorganism, having American Type Culture Collection accession numbers ATCC 53570 and 53571, in a biologically pure culture aseptically collected from a deep subsurface habitat and enhanced, mineralizes trichloroethylene and tetrachloroethylene to HCl, H.sub.2 O and Co.sub.2 under aerobic conditions stimulated by methane, acetate, methanol, tryptone-yeast extract, propane and propane-methane.

  10. Iron enhanced abiotic degradation of chlorinated hydrocarbons

    SciTech Connect

    Chen, C.T.

    1995-10-01

    Since the 1970s, several researchers have investigated the ability of certain zero-valent metals or alloys to enhance the degradation of halogenated organic compounds in contaminated water. Iron, zinc, aluminum, brass, copper, and stainless steel have been studied at various times with varying degrees of success. Gillham and O`Hannesin have recently made a literature review and conducted tests on 14 halogenated aliphatic compounds using zero-valent iron as an enhancing agent. The results showed that rapid dehalogenation occurred on all of the compounds tested except dichloromethane. Based on these test results, EnviroMetal Technologies, Inc. proposed to remediate groundwater contaminated with chlorinated organic compounds using this technology. The EPA Superfund Innovative Technology Evaluation (SITE) program has accepted this technology for demonstration. This demonstration project will include two processes, above ground reactor and in situ permeable wall. The demonstration on the above ground reactor is being conducted at a site in Wayne, New Jersey. The main contaminants at this site are tetrachloroethene (PCE) and trichloroethene (TCE). The in situ permeable wall process will be conducted at a site in upstate New York. This site is a shallow sand aquifer containing TCE, dichloroethenes, and 1,1,1-trichloroethane.

  11. Chlorinated hydrocarbons in flatfishes from the Southern California, USA, Bight

    SciTech Connect

    Schiff, K.; Allen, M.J.

    2000-06-01

    Although inputs of chlorinated hydrocarbon compounds to the Southern California Bight (SCB) are presently low, historical deposits represent a source of bioaccumulation potential to sediment-associated fauna. To assess this bioaccumulation potential, 14 chlorinated hydrocarbon classes were measured in livers of three species of flatfish collected from 63 randomly selected sites on the coastal shelf between Point Conception and the United States-Mexico international border. Tissue contamination was widespread throughout the SCB, but was limited to just two chlorinated hydrocarbon classes. Virtually 100% of Pacific sanddab (Citharichthys sordidus) and longfin sanddab (Citharichthys xanthostigma) populations were estimated to be contaminated with dichlorodiphenyltrichloroethane (total DDT = sum of o.p{prime} and p,p{prime} isomers of DDT + dichlorodiphenyldichloroethylene [DDE] + dichlorodiphenyldichloroethane [DDD]) and/or polychlorinated biphenyls (total PCBs). Total DDT also contaminated the majority (64%) of the Dover sole (Microstomus pacificus) population in the SCB. Total PCB measurements in tissues of SCB flatfish were dominated by 12 congeners (52, 66, 87, 101, 105, 118, 128, 138, 153, 170, 180, and 187), which averaged 95% of the combined mass of the 27 congeners analyzed. Sediment concentrations accounted for most of the variability observed in tissue concentrations for 8 of these 12 congeners and total PCBs. Normalized sediment concentrations were also significantly correlated to normalized tissue concentrations for total DDT and p,p{prime}-DDE. Tissue concentrations measured in this study from reference areas of the SCB were compared to tissue concentrations measured form reference areas in studies conducted in 1977 and 1985. Total DDT and total PCB liver concentrations were found to have decreased one to two orders of magnitude in pacific and longfin sanddabs between 1985 and 1994. Total DDT and total PCB liver concentrations decreased 5- to 35-fold in

  12. Chlorine residuals and haloacetic acid reduction in rapid sand filtration.

    PubMed

    Chuang, Yi-Hsueh; Wang, Gen-Shuch; Tung, Hsin-hsin

    2011-11-01

    It is quite rare to find biodegradation in rapid sand filtration for drinking water treatment. This might be due to frequent backwashes and low substrate levels. High chlorine concentrations may inhibit biofilm development, especially for plants with pre-chlorination. However, in tropical or subtropical regions, bioactivity on the sand surface may be quite significant due to high biofilm development--a result of year-round high temperature. The objective of this study is to explore the correlation between biodegradation and chlorine concentration in rapid sand filters, especially for the water treatment plants that practise pre-chlorination. In this study, haloacetic acid (HAA) biodegradation was found in conventional rapid sand filters practising pre-chlorination. Laboratory column studies and field investigations were conducted to explore the association between the biodegradation of HAAs and chlorine concentrations. The results showed that chlorine residual was an important factor that alters bioactivity development. A model based on filter influent and effluent chlorine was developed for determining threshold chlorine for biodegradation. From the model, a temperature independent chlorine concentration threshold (Cl(threshold)) for biodegradation was estimated at 0.46-0.5mgL(-1). The results imply that conventional filters with adequate control could be conducive to bioactivity, resulting in lower HAA concentrations. Optimizing biodegradable disinfection by-product removal in conventional rapid sand filter could be achieved with minor variation and a lower-than-Cl(threshold) influent chlorine concentration. Bacteria isolation was also carried out, successfully identifying several HAA degraders. These degraders are very commonly seen in drinking water systems and can be speculated as the main contributor of HAA loss. PMID:21974919

  13. Supported metal nanoparticles for the remediation of chlorinated hydrocarbons

    NASA Astrophysics Data System (ADS)

    Schrick, Bettina

    Zero valent iron filings are currently being used in pilot scale field studies to dehalogenate toxic chlorinated hydrocarbons from contaminated surface- and groundwater. Iron filings reduce trichloroethylene (TCE), a model contaminant, via two interconnected degradation pathways: (a) reductive beta-elimination and (b) sequential hydrogenolysis, in which each chlorine atom is sequentially replaced by hydrogen. For the latter pathway, problems arise because the dehalogenation rate decreases as the number of chlorine atoms in the molecule decreases. Therefore, some of the products formed, such as vinyl chloride (VC), are more toxic than the parent compound (TCE), and are only slowly reduced by iron. To improve the rate, cost and technique of remediation for chlorinated hydrocarbons, zero valent nickel-iron (Ni-Fe) nanoparticles have been developed. To elucidate the dehalogenation reaction and particularly the product distributions from a mechanistic standpoint, the roles that nickel and iron play in the dehalogenation of TCE were studied. On the bimetallic particles, the reaction occurs by nickel-catalyzed hydrodechlorination. As the iron actively corrodes, the cathodically protected nickel surface chemisorbs hydrogen ions, and TCE adsorbed to the Ni surface is thus hydrogenated. This reaction competes kinetically with the evolution of molecular hydrogen. Hydrogenolysis of the C-Cl bond results in the formation of linear, as well as branched saturated and unsaturated hydrocarbons. Dispersing the nanometals onto high surface area supports, such as hydrophilic carbon or polyacrylic acid (PAA), provides a delivery vehicle for the reactive nanoparticles. The support acts as a nanometal carrier, and may also help preconcentrate the toxins, and provide a conductive pathway for electron transfer. In general, supports are expected to stabilize the nanoparticles and give an increased surface to volume ratio. The carbon- and PAA-supported nanometals form a permanent suspension

  14. A chemical kinetic modeling study of chlorinated hydrocarbon combustion

    SciTech Connect

    Pitz, W.J.; Westbrook, C.K.

    1990-09-05

    The combustion of chloroethane is modeled as a stirred reactor so that we can study critical emission characteristics of the reactor as a function of residence time. We examine important operating conditions such as pressure, temperature, and equivalence ratio and their influence on destructive efficiency of chloroethane. The model uses a detailed chemical kinetic mechanism that we have developed previously for C{sub 3} hydrocarbons. We have added to this mechanism the chemical kinetic mechanism for C{sub 2} chlorinated hydrocarbons developed by Senkan and coworkers. In the modeling calculations, sensitivity coefficients are determined to find which reaction-rate constants have the largest effect on destructive efficiency. 24 refs., 6 figs., 1 tab.

  15. Carbon and chlorine isotopologue fractionation of chlorinated hydrocarbons during diffusion in water and low permeability sediments

    NASA Astrophysics Data System (ADS)

    Wanner, Philipp; Hunkeler, Daniel

    2015-05-01

    To identify reactive processes in diffusion dominated water-saturated systems using compound-specific isotope analysis (CSIA), the effect of the diffusive transport process on isotope ratios needs to be known. This study aims to quantify the magnitude of carbon and chlorine isotopologue fractionation of two chlorinated hydrocarbons (trichloroethene (TCE) and 1,2-dichloroethane (1,2-DCA)) during diffusion in the aqueous phase and to relate for the first time laboratory with field results. Diffusion coefficient ratios in the aqueous phase were experimentally quantified with a modified Stokes diffusion cell. The experiment revealed a significant shift of carbon and chlorine isotopologue ratios of TCE and 1,2-DCA during diffusion. For both TCE and 1,2-DCA, the magnitude of the shift of chlorine isotopologue ratios was larger (TCE: D132/D130 = 0.99963 ± 0.00003; 1,2-DCA: D102/D100 = 0.99939 ± 0.00003) in comparison to carbon isotopologue ratios (TCE: D131/D130 = 0.99978 ± 0.00006; 1,2-DCA: D101/D100 = 0.99977 ± 0.00004), which is consistent with the larger mass difference between stable chlorine compared to carbon isotopes. Determined diffusion coefficients for carbon and chlorine isotopologues of TCE and 1,2-DCA follow an inverse power law form (D ∝m-β) with β < 0.5 revealing that the magnitude of isotopologue fractionation of TCE and 1,2-DCA is lower than in the previously postulated kinetic theory (D ∝m-0.5). To relate laboratory with field results, a water-saturated clay core from a VOC contaminated site was retrieved and subsampled as a function of depth to assess possible shifts in isotopologue ratios during downward diffusion of VOCs into the low permeable clay. Observed small shifts of TCE carbon and chlorine isotopologue ratio profiles were consistent with laboratory determined diffusion coefficient ratios, demonstrated by a 1D-diffusion model. Further 1D-simulations for shorter diffusion periods (5-10 years) than observed in the retrieved clay core

  16. Electron beam degradation of chlorinated hydrocarbons in air

    NASA Astrophysics Data System (ADS)

    Prager, L.; Langguth, H.; Rummel, S.; Mehnert, R.

    1995-09-01

    Using a low-energy electron accelerator (180 keV, 3 kW) synthetic air polluted with chlorinated hydrocarbons such as cis-dichloro-, trichloro- and perchloroethene was irradiated in a flow system. Already at doses of 2.5 kGy, more than 90 vol% of the initial pollutant concentration (2-50 ppm) could be removed. As main products HCl, CO, chloromethanes, chloroacetyl chlorides and phosgene were identified. After hydrolysis of phosgene and chloroacteyl chlorides in a wet scrubbing system, the chlorine balance shows nearly complete mineralization of the pollutants to HCl, CO and CO2. Less than 5 vol% of chloromethanes and about 0.1 vol% chloroacetic acids were detected after irradiation and hydrolysis. An attempt is made to describe the degradation mechanism as OH radical induced chain reaction. The OH radical adds to the ethene double bond. The resulting adduct releases a chlorine radical. In presence of oxygen a chain reaction is initiated by this radical, which leads to decomposition of the chloroethenes.

  17. Electrochemical SERS detection of chlorinated hydrocarbons in aqueous solutions

    SciTech Connect

    Storey, J.M.E.; Shelton, R.D.; Barber, T.E.; Wachter, E.A. )

    1994-10-01

    An [ital in] [ital situ] method for the determination of trichloroethylene (TCE), perchlorethylene (PCE), chloroform (CHCl[sub 3]) and carbon tetrachloride (CCl[sub 4]) in aqueous solution is described. The method is based on ESERS-a combination of electrochemical methods and surface-enhanced Raman scattering (SERS). Electrochemistry prepares the surface of a copper electrode for SERS and concentrates the analyte on the surface. The formation of common reaction products for chloroalkanes and for chloroalkenes prevents unequivocal differentiation within a specific class of chlorinated hydrocarbons. However, spectroscopic selectivity between the chloroalkane and chloroalkene classes is excellent, while differences in electrochemical response provide a secondary means for differentiating analyte class. Sensitivity was found to be: [lt]1 ppm for TCE; 15 ppm for PCE; 15 ppm for CHCl[sub 3]; and 10 ppm for CCl[sub 4]. Application of the method to groundwater contaminated with TCE has been demonstrated. In combination with a fiber-optic waveguide, the ESERS technique offers potential for remote detection of chlorinated hydrocarbons in groundwater and remediation process streams.

  18. BENEFITS OF MAINTAINING A CHLORINE RESIDUAL IN WATER SUPPLY SYSTEMS

    EPA Science Inventory

    The protection afforded the water consumer by the maintenance of a chlorine residual in water distribution systems was evaluated in laboratory holding tanks and reservoirs and existing municipal water distribution systems. In the laboratory studies, tap water, adjusted to the app...

  19. Iron-carbon composites for the remediation of chlorinated hydrocarbons

    NASA Astrophysics Data System (ADS)

    Sunkara, Bhanu Kiran

    This research is focused on engineering submicron spherical carbon particles as effective carriers/supports for nanoscale zerovalent iron (NZVI) particles to address the in situ remediation of soil and groundwater chlorinated contaminants. Chlorinated hydrocarbons such as trichloroethylene (TCE) and tetrachloroethylene (PCE) form a class of dense non-aqueous phase liquid (DNAPL) toxic contaminants in soil and groundwater. The in situ injection of NZVI particles to reduce DNAPLs is a potentially simple, cost-effective, and environmentally benign technology that has become a preferred method in the remediation of these compounds. However, unsupported NZVI particles exhibit ferromagnetism leading to particle aggregation and loss in mobility through the subsurface. This work demonstrates two approaches to prepare carbon supported NZVI (iron-carbon composites) particles. The objective is to establish these iron-carbon composites as extremely useful materials for the environmental remediation of chlorinated hydrocarbons and suitable materials for the in situ injection technology. This research also demonstrates that it is possible to vary the placement of iron nanoparticles either on the external surface or within the interior of carbon microspheres using a one-step aerosol-based process. The simple process of modifying iron placement has significant potential applications in heterogeneous catalysis as both the iron and carbon are widely used catalysts and catalyst supports. Furthermore, the aerosol-based process is applied to prepare new class of supported catalytic materials such as carbon-supported palladium nanoparticles for ex situ remediation of contaminated water. The iron-carbon composites developed in this research have multiple functionalities (a) they are reactive and function effectively in reductive dehalogenation (b) they are highly adsorptive thereby bringing the chlorinated compound to the proximity of the reactive sites and also serving as adsorption

  20. RECOMMENDED PRACTICES FOR ON-LINE MEASUREMENT OF RESIDUAL CHLORINE IN WASTEWATERS

    EPA Science Inventory

    This document provides users with information that assists them in specifying, installing, calibrating, maintaining and monitoring the subsequent performance of on-line residual chlorine analyzers in wastewater treatment plants. An on-line residual chlorine analyzer must have, am...

  1. Bioconcentration of chlorinated hydrocarbons from sediment by oligochaetes

    SciTech Connect

    Connell, D.W.; Bowman, M.; Hawker, D.W.

    1988-12-01

    Previously published data on the accumulation of 15 chlorinated hydrocarbons from sediment by oligochaetes have been interpreted on the basis of bioconcentration from interstitial water. Calculation of the interstitial water concentration allowed determination of uptake and clearance rate constants together with bioconcentration factors (KB) for these compounds. These three factors each exhibited a systematic relationship to the octanol/water partition coefficient (KOW). The log KB versus log KOW relationship was roughly linear over the log KOW range from 4.4 to 6.4 and displayed an increasing nonlinear deviation for log KOW values greater than 6.4. These relationships are qualitatively similar to those established for other aquatic organisms where bioconcentration from water was the mechanism involved. This suggests that interstitial water may be the phase from which lipophilic compounds in sediment are bioconcentrated by oligochaetes. An expression relating the bioconcentration factor to the biotic concentration and various sediment characteristics has also been developed.

  2. Effects of chlorinated hydrocarbon insecticides upon quail and pheasants

    USGS Publications Warehouse

    DeWitt, J.B.

    1955-01-01

    Previous studies had shown that heavy or repeated applications of DDT resulted in decreases.in bird populations, but long-range effects of this and other chlorinated hydrocarbon insecticides had not been fully evaluated. Experiments were conducted to determine toxiCitY to quail and pheasants of aldrin, dieldrin, endrin, and strobane, and to determine effects of these compounds upon survival, growth, and reproduction....Feeding of diets containing 0.02% DDT to breeding quail resulted in significant decreases in hatchability of eggs and in viability of chiCks. Similar results were obtained by feeding 0.001% dieldrin, but effects upon reproduct.ion of short-term feeding of aldrin and endrin could not be determined....Aldrin, dieldrin, and endrin were lethal to both male and female quail when fed at levels of 0.0005% in the diets. Female pheasants appeared more resistant than males to the effects of these compounds.

  3. Determination of Residual Chlorine and Turbidity in Drinking Water. Instructor's Manual.

    ERIC Educational Resources Information Center

    Office of Water Program Operations (EPA), Cincinnati, OH. National Training and Operational Technology Center.

    This instructor's guide presents analytical methods for residual chlorine and turbidity. Topics include sample handling, permissable concentration levels, substitution of residual chlorine for bacteriological work, public notification, and the required analytical techniques to determine residual chlorine and turbidity. This publication is intended…

  4. Determination of Residual Chlorine and Turbidity in Drinking Water. Student Manual.

    ERIC Educational Resources Information Center

    Office of Water Program Operations (EPA), Cincinnati, OH. National Training and Operational Technology Center.

    This student's manual covers analytical methods for residual chlorine and turbidity. Topics include sample handling, permissable concentration levels, substitution of residual chlorine for bacteriological work, public notification, and the required analytical techniques to determine residual chlorine and turbidity. The publication is intended for…

  5. A New, Rapid, Precise and Sensitive Method for Chlorine Stable Isotope Analysis of Chlorinated Aliphatic Hydrocarbons

    NASA Astrophysics Data System (ADS)

    van Acker, M. R.; Shahar, A.; Young, E. D.; Coleman, M. L.

    2005-12-01

    Chlorinated aliphatic hydrocarbons (CAH) are recognized common groundwater contaminants. Because of their physico-chemical properties, their lifespan in groundwater is in the order of decades (Pankow and Cherry, 1996). Stable isotopes can play a role in determining the rate and extent of CAH attenuation (Slater, 2003). The use of chlorine has been hampered by the current time consuming and insensitive analytical methods. We present a new analytical procedure to measure chlorine stable isotope values using a gas chromatograph coupled to a multi-collector inductively coupled mass spectrometer (GC-MC-ICP-MS). The GC has a Porapack Q packed column. The carrier gas was helium and the temperature was constant at 160°C. The GC was coupled to the MC-ICP-MS by heated stainless steel tubing. Our high resolution spectra showed that 37Cl is free of its main interference 36Ar-H over a range of 0.004 amu. Two pure CAH, trichloroethene (TCE) and tetrachloroethene (PCE), were used for zero enrichment (sample relative to itself) and standard-sample difference measurements. Integrations and background corrections of transient signals were performed using Microsoft Excel after import of the raw data from the MC-ICPMS acquisition software. Zero enrichment tests with TCE and PCE yielded δ37Cl of -0.04±0.16‰ and -0.03±0.17‰, respectively, results for sample injections of 0.12 to 0.02 microliters. Accuracy was tested by injecting 0.24 microliters of a 50/50 mixture of TCE and PCE of known isotopic compositions as the difference between the two solvents was of paramount interest. The δ37Cl(TCE) value of PCE was -1.99±0.16‰. A highly satisfactory comparison with the conventional method is shown by published values for TCE and PCE, -2.04±0.12‰ and -0.30±0.14‰, respectively (Jendrzejewski et al., 2001), giving a δ37Cl(TCE) value for PCE of -2.34±0.18‰. These tests of the GC-MC-ICP-MS method showed that we can obtain reproducible and accurate Cl isotope values using an

  6. Analysis of residual chlorine in simple drinking water distribution system with intermittent water supply

    NASA Astrophysics Data System (ADS)

    Goyal, Roopali V.; Patel, H. M.

    2015-09-01

    Knowledge of residual chlorine concentration at various locations in drinking water distribution system is essential final check to the quality of water supplied to the consumers. This paper presents a methodology to find out the residual chlorine concentration at various locations in simple branch network by integrating the hydraulic and water quality model using first-order chlorine decay equation with booster chlorination nodes for intermittent water supply. The explicit equations are developed to compute the residual chlorine in network with a long distribution pipe line at critical nodes. These equations are applicable to Indian conditions where intermittent water supply is the most common system of water supply. It is observed that in intermittent water supply, the residual chlorine at farthest node is sensitive to water supply hours and travelling time of chlorine. Thus, the travelling time of chlorine can be considered to justify the requirement of booster chlorination for intermittent water supply.

  7. Trends in chlorinated hydrocarbon levels in Hudson River basin sediments.

    PubMed Central

    Bopp, R F; Chillrud, S N; Shuster, E L; Simpson, H J; Estabrooks, F D

    1998-01-01

    Analysis of sections from dated sediment cores were used to establish geographic distributions and temporal trends of chlorinated hydrocarbon contaminant levels in sediments from natural waters of the Hudson River basin. Radiometric dating was based primarily on the depth distribution of 137(Cs) in the cores and on the occurrence of detectable levels of 7(Be) in surface sediment samples. Eighteen sampling sites included several along the main stem of the Hudson, its major tributaries, and components of the New York/New Jersey (NY/NJ) harbor complex. Drinking-water reservoirs were sampled to place upper limits on atmospheric inputs. Core sections were analyzed for polychlorinated biphenyls (PCBs), 1,1,1-trichloro-2,2-bis(p-chlorophenyl) ethane (DDT)-derived compounds, chlordane, and dioxins. Sediment concentrations of most contaminants at most sites have decreased significantly since the mid-1960s. The data provide a basinwide perspective on major point-source inputs of PCBs to the upper Hudson River and of 2,3,7,8-tetrachlorodibenzo-p-dioxin and DDT to the lower Passaic River. Evidence was found for significant but poorly characterized sources of PCBs and chlordane to the western NY/NJ harbor, and of highly chlorinated dioxins to the upstream sites on the main stem of the Hudson. The results indicate that analysis of dated sediment samples is a most effective and efficient monitoring tool for the study of large-scale geographic and temporal trends in levels of particle-associated contaminants. Images Figure 1 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:9703496

  8. Chlorinated hydrocarbons in plant foliage: an indication of the tropospheric contamination level

    SciTech Connect

    Gaggi, C.; Bacci, E.; Calamari, D.; Fanelli, R.

    1985-01-01

    Levels of some chlorinated hydrocarbons in foliage from the Italian peninsula and other countries of the world are reported. The use of plant leaves in monitoring and for a prediction of potential environmental distribution of persistent hydrophobic pollutants is discussed.

  9. CHLORINATED HYDROCARBON DEGRADATION IN PLANTS: MECHANISMS AND ENHANCEMENT OF PHYTOREMEDIATION OF GROUNDWATER CONTAMINATION

    EPA Science Inventory

    Several varieties of transgenic poplar containing cytochrome P-450 2E1 have been constructed and are undergoing tests. Strategies for improving public acceptance and safety of transgenic poplar for chlorinated hydrocarbon phytoremediation are being developed. We have discovered a...

  10. EPA (ENVIRONMENTAL PROTECTION AGENCY) METHOD STUDY 22. METHOD 612-CHLORINATED HYDROCARBONS

    EPA Science Inventory

    An interlaboratory study in which 20 laboratories participated was conducted to provide precision and accuracy statements for the proposed EPA Method 612 - Chlorinated Hydrocarbons for measuring concentrations of the Category 3 chemicals hexachloroethane, hexachlorobutadiene, 2-c...

  11. ANAEROBIC TRANSFORMATION OF CHLORINATED ALIPHATIC HYDROCARBONS IN A SAND AQUIFER BASED ON SPATIAL CHEMICAL DISTRIBUTIONS

    EPA Science Inventory

    We estimated the distribution of chlorinated aliphatic hydrocarbons (CAHs) from groundwater samples collected along three transects in a sand aquifer. richloroethylene (TCE) leaked and contaminated the aquifer probably more than a decade before we collected the measurements. he d...

  12. CHEMICAL DISTRIBUTION AND ANAEROBIC TRANSFORMATION OF CHLORINATED ALIPHATIC HYDROCARBONS IN A SAND AQUIFER

    EPA Science Inventory

    We estimated the distribution of chlorinated aliphatic hydrocarbons (CAHS) from groundwater samples collected along three transects in a sand aquifer. richloroethylene (TCE) leaked and contaminated the aquifer probably more than a decade before we collected the measurements. he d...

  13. Hydrous pyrolysis/oxidation process for in situ destruction of chlorinated hydrocarbon and fuel hydrocarbon contaminants in water and soil

    DOEpatents

    Knauss, Kevin G.; Copenhaver, Sally C.; Aines, Roger D.

    2000-01-01

    In situ hydrous pyrolysis/oxidation process is useful for in situ degradation of hydrocarbon water and soil contaminants. Fuel hydrocarbons, chlorinated hydrocarbons, polycyclic aromatic hydrocarbons, petroleum distillates and other organic contaminants present in the soil and water are degraded by the process involving hydrous pyrolysis/oxidation into non-toxic products of the degradation. The process uses heat which is distributed through soils and water, optionally combined with oxygen and/or hydrocarbon degradation catalysts, and is particularly useful for remediation of solvent, fuel or other industrially contaminated sites.

  14. Accumulation and diagenesis of chlorinated hydrocarbons in lacustrine sediments

    USGS Publications Warehouse

    Elsenreich, S.J.; Capel, P.D.; Robbins, J.A.; Bourbonniere, R.

    1989-01-01

    Two sediment cores were taken from the Rochester Basin of eastern Lake Ontario and analyzed for the radionuclides 210Pb and 137Cs and several high molecular weight chlorinated hydrocarbons (CHs). The two sites are geographically proximate but differ in sedimentation rate, permitting sedimentation-dependent processes to be factored out. The 210Pb chronology showed a mixed depth of 3-5 cm and an intrinsic time resolution of 11-14 years. Vertically integrated numbers of deposit-feeding oligochaete worms and burrowing organisms are insufficient to homogenize the sediment on the time scale of CH inputs, which are non steady state. U.S. production and sales of polychlorinated biphenyls (PCBs), DDT, Mirex, and hexachlorobenzene (HCB), as determinants of the shape of the input function, adequately predict the overall shape and, in many cases, details in the sedimentary profile. Sediment focusing factors (FF) inferred from 137Cs and 210Pb inventories averaged 1.17 and 1.74 for cores E-30 and G-32, respectively. This permitted CH accumulation rates to be corrected for focusing. Apparent molecular diffusion coefficients modeled for many of the CHs were about (1-3) ?? 10-9 cm2/s.

  15. Hydrocarbon-solvent based cleaners as replacements for chlorinated and CFC solvents

    SciTech Connect

    Schreiner, J.L.; Berlin, E.P.

    1995-12-31

    Chlorinated and CFC solvents have been used for about 30 years to remove various contaminants from products during the manufacturing process. Among the contaminants being removed are oils, greases, and waxes that have petroleum products as the base. Prior to the advent of the chlorinated solvents petroleum distillates were used for these cleaning operations. Processing improvements over the past 30 years now permit production of higher purity hydrocarbons solvents that can be used as replacements for the chlorinated and CFC solvents being phased out. These hydrocarbon solvents are well suited for removal of the various petroleum based contaminants, as one recalls the old adage {open_quotes}like dissolves like.{close_quotes}

  16. Assimilation of chlorinated alkanes by hydrocarbon-utilizing fungi

    SciTech Connect

    Murphy, G.L.; Perry, J.J.

    1984-12-01

    The fatty acid compositions of two filamentous fungi (Cunninghamella elegans and Penicillium zonatum) and a yeast (Candida lipolytica) were determined after the organisms were grown on 1-chlorohexadecane or 1-chlorooctadecane. These organisms utilized the chlorinated alkanes as sole sources of carbon and energy. Analyses of the fatty acids present after growth on the chlorinated alkanes indicated that 60 to 70% of the total fatty acids in C. elegans were chlorinated. Approximately 50% of the fatty acids in C. lipolytica were also chlorinated. P. zonatum contained 20% 1-chlorohexadecanoic acid after growth on either substrate but did not incorporate C/sub 18/ chlorinated fatty acids.

  17. BIOTRANSFORMATION OF MIXTURES OF CHLORINATED ALIPHATIC HYDROCARBONS BY AN ACETATE-GROWN METHANOGENIC ENRICHMENT CULTURE. (R825549C053)

    EPA Science Inventory

    Biotransformation of chlorinated aliphatic hydrocarbons under anaerobic conditions has received considerable attention due to the prevalence of these compounds as groundwater contaminants. However, information concerning the impact of mixtures of chlorinated compounds on their...

  18. Using trees to remediate groundwaters contaminated with chlorinated hydrocarbons. 1998 annual progress report

    SciTech Connect

    Strand, S.E.; Gordon, M.P.

    1998-06-01

    'Industrial practices in the past have resulted in contamination of groundwater with chlorinated hydrocarbons (CHCs) at many DOE sites, such as Hanford and Savannah River. Such contamination is a major problem because existing groundwater remediation technologies are expensive and difficult. An inexpensive method for groundwater remediation is greatly needed. Trees could be used to remediate CHC polluted groundwater at minimal cost (phytoremediation). Before phytoremediation can be extensively applied, the authors must determine the range of compounds that are attacked, the effects of metabolic products on the plants and the environment, and the effect of transpiration and concentration of CHC on uptake and metabolism. They will test the ability of hybrid poplar to take up and transform the chlorinated methanes, ethanes and ethylenes. The rate of uptake and transformation by poplar of TCE as a function of concentration in the soil, transpiration rate and illumination level will be determined. Methods will be developed to permit rapid testing of plants from contaminated sites for species able to oxidize and sequester chlorinated compounds. They will identify the nature of the bound residues of TCE metabolism in poplar. They will identify the mechanisms involved in CHC oxidation in poplar and use genetic manipulations to enhance that activity. They will introduce the genes for mammalian cytochrome P-450-IIE1, known to oxidize light CHCs such as TCE to attempt to increase the CHC metabolism capacity of poplar. The results of this research will place phytoremediation of CHCs on a firm scientific footing, allowing a rational assessment of its application to groundwater contamination. This report summarizes the results of the first 1.5 years of work on a three-year project.'

  19. CHEMICAL INDUCTION OF TUMORS IN OYSTERS BY A MIXTURE OF AROMATIC AND CHLORINATED HYDROCARBONS, AMINES, AND METALS

    EPA Science Inventory

    Tumors were induced in eastern oysters (Crassotrea virginica) by a mixture f aromatic hydrocarbons, an aromatic amine, polychlori-nated biphenyls, chlorinated hydrocarbons, a nitrosoamine and heavy metals. idney and nteric tumors developed in oysters following exposure to a mixtu...

  20. Method for removing chlorine compounds from hydrocarbon mixtures

    DOEpatents

    Janoski, E.J.; Hollstein, E.J.

    1984-09-29

    A process for removing halide ions from a hydrocarbon feedstream containing halogenated hydrocarbons wherein the contaminated feedstock is contacted with a solution of a suitable oxidizing acid containing a lanthanide oxide, the acid being present in a concentration of at least about 50 weight percent for a time sufficient to remove substantially all of the halide ion from the hydrocarbon feedstock.

  1. Method for removing chlorine compounds from hydrocarbon mixtures

    DOEpatents

    Janoski, Edward J.; Hollstein, Elmer J.

    1985-12-31

    A process for removing halide ions from a hydrocarbon feedstream containing halogenated hydrocarbons wherein the contaminated feedstock is contacted with a solution of a suitable oxidizing acid containing a lanthanide oxide, the acid being present in a concentration of at least about 50 weight percent for a time sufficient to remove substantially all of the halide ion from the hydrocarbon feedstock.

  2. Chloroxyanion Residue Quantification in Cantaloupes Treated with Chlorine Dioxide Gas.

    PubMed

    Kaur, Simran; Smith, David J; Morgan, Mark T

    2015-09-01

    Previous studies show that treatment of cantaloupes with chlorine dioxide (ClO2) gas at 5 mg/liter for 10 min results in a significant reduction (P < 0.05) in initial microflora, an increase in shelf life without any alteration in color, and a 4.6- and 4.3-log reduction of Escherichia coli O157:H7 and Listeria monocytogenes, respectively. However, this treatment could result in the presence of chloroxyanion residues, such as chloride (Cl(-)), chlorite (ClO2(-)), chlorate (ClO3(-)), and perchlorate (ClO4(-)), which, apart from chloride, are a toxicity concern. Radiolabeled chlorine dioxide ((36)ClO2) gas was used to describe the identity and distribution of chloroxyanion residues in or on cantaloupe subsequent to fumigation with ClO2 gas at a mean concentration of 5.1 ± 0.7 mg/liter for 10 min. Each treated cantaloupe was separated into rind, flesh, and mixed (rind and flesh) sections, which were blended and centrifuged to give the corresponding sera fractions. Radioactivity detected, ratio of radioactivity to mass of chlorite in initial ClO2 gas generation reaction, and distribution of chloroxyanions in serum samples were used to calculate residue concentrations in flesh, rind, and mixed samples. Anions detected on the cantaloupe were Cl(-) (∼ 90%) and ClO3(-) (∼ 10%), located primarily in the rind (19.3 ± 8.0 μg of Cl(-)/g of rind and 4.8 ± 2.3 μg of ClO3(-)/g of rind, n = 6). Cantaloupe flesh (∼ 200 g) directly exposed to(36)ClO2 gas treatment showed the presence of only Cl(-) residues (8.1 ± 1.0 μg of Cl(-)/g of flesh, n = 3). Results indicate chloroxyanion residues Cl(-) and ClO3(-) are only present on the rind of whole cantaloupes treated with ClO2 gas. However during cutting, residues may be transferred to the fruit flesh. Because Cl(-) is not toxic, only ClO3(-) would be a toxicity concern, but the levels transferred from rind to flesh are very low. In the case of fruit flesh directly exposed to ClO2 gas, only nontoxic Cl(-) was detected. This

  3. Chloroxyanion residues in cantaloupe and tomatoes after chlorine dioxide gas sanitation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chlorine dioxide gas is effective at cleansing fruits and vegetables of bacterial pathogens and(or) rot organisms, but few data are available on chemical residues remaining subsequent to chlorine gas treatment. Therefore, studies were conducted to quantify chlorate and perchlorate residues after tom...

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

    SciTech Connect

    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.

  5. Formation of stable chlorinated hydrocarbons in weathering plant material

    SciTech Connect

    Myneni, Satish C. B.

    2001-10-01

    Though several chlorinated organic compounds produced by humans are carcinogenic and toxic, some are also produced by the biotic and abiotic processes in the environment. In situ x-ray spectroscopy data indicate that natural organic matter in soils, sediments, and natural waters contain stable, less volatile organic compounds with chlorinated phenolic and aliphatic groups as the principal Cl forms. These compounds are formed at rapid rates from the transformation of inorganic Cl during humification of plant material and, thus, play a critical role in the cycling of Cl and of several major and trace elements in the environment and may influence human health. [References: 19

  6. Determination of PCBs and chlorinated hydrocarbons in marine mammal tissues.

    PubMed

    Schantz, M M; Koster, B J; Wise, S A; Becker, P R

    1993-11-01

    Selected tissues (blubber, liver, kidney and muscle) from marine mammals, which were collected as part of the Alaska Marine Mammal Tissue Archival Project (AMMTAP), were analyzed for polychlorinated biphenyl (PCB) congeners and chlorinated pesticides. Concentrations of these compounds in the different tissues were compared and blubber was selected as the primary tissue for organic contaminant analyses for the AMMTAP based on higher levels (1-2 orders of magnitude) in this tissue compared to liver, kidney and muscle. Concentrations for 15 PCB congeners and 12 chlorinated pesticides are reported for 10 different animals of three species (northern fur seal, ringed seal and belukha whale) from five different sites. PMID:8272838

  7. Transfer of chlorinated hydrocarbons in the food chain lichen > reindeer > man

    SciTech Connect

    Villeneuve, J.P.; Holm, E.; Cattini, C.

    1985-01-01

    Lichen Caladonia alpestris collected in the Northern part of Sweden were analyzed together with samples of reindeer and wolf living in the same area. From these results one can estimate the annual intake of these compounds by Lapplanders. The amount ingested by lapplanders is far below the maximum permissible limit set for the intake of chlorinated hydrocarbons through food.

  8. Modeling the national chlorinated hydrocarbon supply chain and effects of disruption.

    SciTech Connect

    Sun, Amy Cha-Tien; Downes, Paula Sue; Blair, Angela S.; Welk, Margaret Ellen

    2010-03-01

    Chlorinated hydrocarbons represent the precursors for products ranging from PVC and refrigerants to pharmaceuticals. Natural or manmade disruptions that affect the availability of these products nationally have the potential to affect a wide range of markets, from healthcare to construction. Sandia National Laboratories (Sandia) has developed datasets and models that allow the analysis of the interdependencies within the chlorine chemical supply chain and consequences of disruptions. Combining data on plant locations, transportation, utilities, and the chemical supply chain itself, with modeling tools such as N-ABLE, a Sandia-developed agent based modeling system, allows Sandia to model this complex system dynamically. Sandia has used the N-ABLE technology to simulate a disruption to the chlorinated hydrocarbon supply chain caused by a hurricane striking the Louisiana coast. This paper presents results and conclusions from this analysis.

  9. Flux of transuranium nuclides and chlorinated hydrocarbons in the northwestern Mediterranean

    NASA Astrophysics Data System (ADS)

    Fowler, S. W.; Ballestra, S.; Villeneuve, J.-P.

    1990-09-01

    The transuranium nuclides, plutonium and americium, and selected chlorinated hydrocarbon compounds have been measured in sediment trap samples, bottom sediments and waters. These measurements have been used to quantify vertical fluxes and elucidate particulate biogeochemical cycles, of these man-made contaminants in the northwestern Mediterranean. Sediment trap experiments in the Gulf of Lions (Lacaze-Duthiers Canyon) have shown that transuranic fluxes are considerably higher in the Gulf of Lions, than those which have been reported for the northeast Pacific; principally this is due to the relatively high mass fluxes in this region of the Mediterranean. Water, surface sediment and sediment trap data indicate that 241Am is being transported downward (via particle settling) more rapidly than 239+240Pu. From direct flux measurement, residence times for 239+240Pu and 241Am in the upper 300 m were computed to be 2.5 and 0.14 years, respectively. Comparison of 239+240Pu concentrations in the water column, in 1986, with similar measurements made 5-11 years earlier suggests that fallout input to the Mediterranean has decreased by nearly a factor of 2 during the period 1975-1986. Fluxes of PCB, HCB, γ-HCH and DDT residues varied by as much as an order of magnitude, or more, both temporally and with depth. The average fluxes of most of the compounds in the Lacaze-Duthiers Canyon, during 1985-1986, were quite similar to those measured off the coast of Monaco several years earlier. Generally, the increased chlorinated hydrocarbon fluxes observed with depth were a direct result of the much higher mass fluxes which occurred at depth. Demonstrated differences in PCB concentrations in the settling particles, deposited surface sediments and overlying sediment floc indicate that simple bottom sediment resuspension is not a major contributor to the enhanced PCB flux noted at depth. The PCB concentration in sedimenting particulate material collected from deeper waters, is similar to

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

    PubMed

    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

  11. POPULATION DIVERSITY IN MODEL DRINKING WATER BIOFILMS RECEIVING CHLORINE OR MONOCHLORAMINE RESIDUAL

    EPA Science Inventory

    Most water utilities add monochloramine or chlorine as a residual disinfectant in potable water distribution systems (WDS) to control bacterial regrowth. While monochloramine is considered more stable than chlorine, little is known about the fate of this disinfectant or the effec...

  12. Biodegradation of individual and multiple chlorinated aliphatic hydrocarbons by methane-oxidizing cultures.

    PubMed Central

    Chang, H L; Alvarez-Cohen, L

    1996-01-01

    The microbial degradation of chlorinated and nonchlorinated methanes, ethanes, and ethanes by a mixed methane-oxidizing culture grown under chemostat and batch conditions is evaluated and compared with that by two pure methanotrophic strains: CAC1 (isolated from the mixed culture) and Methylosinus trichosporium OB3b. With the exception of 1,1-dichloroethylene, the transformation capacity (Tc) for each chlorinated aliphatic hydrocarbon was generally found to be in inverse proportion to its chlorine content within each aliphatic group (i.e., methanes, ethanes, and ethenes), whereas similar trends were not observed for degradation rate constants. Tc trends were similar for all methane-oxidizing cultures tested. None of the cultures were able to degrade the fully chlorinated aliphatics such as perchloroethylene and carbon tetrachloride. Of the four cultures tested, the chemostat-grown mixed culture exhibited the highest Tc for trichloroethylene, cis-1,2-dichloroethylene, tetrachloroethane, 1,1,1-trichloroethane, and 1,2-dichloroethane, whereas the pure batch-grown OB3b culture exhibited the highest Tc for all other compounds tested. The product toxicity of chlorinated aliphatic hydrocarbons in a mixture containing multiple compounds was cumulative and predictable when using parameters measured from the degradation of individual compounds. The Tc for each chlorinated aliphatic hydrocarbon in a mixture (Tcmix) and the total Tc for the mixture (sigma Tcmix) are functions of the individual Tc, the initial substrate concentration (S0), and the first-order rate constant (k/Ks) of each compound in the mixture, indicating the importance of identifying the properties and compositions of all potentially degradable compounds in a contaminant mixture. PMID:8795228

  13. COMPARISON OF METHODS FOR THE DETERMINATION OF TOTAL AVAILABLE RESIDUAL CHLORINE IN VARIOUS SAMPLE MATRICES

    EPA Science Inventory

    Ten different methods for determining total available residual chlorine, all based on the iodine-iodide reaction, were tested without modification on four sample matrices. Their precision was determined by seven replicate determinations. Accuracy as compared to the iodometric sta...

  14. MODELING CHLORINE RESIDUALS IN DRINKING-WATER DISTRIBUTION SYSTEMS

    EPA Science Inventory

    A mass-transfer-based model is developed for predicting chlorine decay in drinking-water distribution networks. The model considers first-order reactions of chlorine to occur both in the bulk flow and at the pipe wall. The overall rate of the wall reaction is a function of the ...

  15. Hydrothermal processing of chlorinated hydrocarbons in a titanium reactor

    SciTech Connect

    Foy, B.R.; Waldthausen, K.; Sedillo, M.A.; Buelow, S.J.

    1996-09-01

    Experiments are reported on the oxidative hydrothermal destruction of chlorinated organics in a corrosion-resistant titanium reactor. Oxidation reaction conditions were 250-500 {degree}C near 650 bar and reaction times of 30-100 s in a continuous-flow reactor. Trichloroacetic acid, trichloroethylene, and 1,1,1-trichloroethane behaved similarly. The organic concentration was approximately 1.5 wt%; hydrogen peroxide was the oxidizer; sodium bicarbonate was added to achieve neutral pH. Hydrolysis occurs at low temperature, producing chloride ion and secondary organics. Carbon dioxide is the sole carbon product at 500 {degree}C. Sodium nitrate and sodium nitrite were also found to be effective oxidizers. Corrosion of the titanium was found to be slight (<0.038 mm/yr). The reaction mixture is likely not a single phase at these conditions. The destruction efficiency for trichloroethylene was estimated as 99.96% at 450 {degree}C and 60 s, with <0.02% conversion to volatile chlorinated organic byproducts. 33 refs., 9 figs., 6 tabs.

  16. Influence of free residual chlorine on cultured human epidermal keratinocytes from normal skin and hypertrophic scars.

    PubMed

    Matsumoto, Y; Mori, H; Hayakawa, A; Ohashi, M

    1995-07-01

    In Japan, public health regulations state that the water in rinsing pools used before swimming should contain 50-100 mg/l of chlorine. We examined the influence of chlorination at high concentrations in rinsing pools on the skin using cultured human epidermal keratinocytes from normal skin and hypertrophic scars. Chlorination of cell culture for 15 min with 200 mg/l of free residual chlorine proved cytotoxic to both types of keratinocytes as did 100 mg/l of free residual chlorine for 1 or 3 consecutive days. Keratinocytes from hypertrophic scars, when cultivated in 100 mg/l of free residual chlorine, were more vulnerable to chlorine than those from normal skin. Cell characteristics of cultured keratinocytes from hypertrophic scars may be somewhat different from those of normal skin. The phenomena observed in this experimental model of the skin suggest that people exposed to chlorine in rinsing pools at concentrations in excess of 200 mg/l for about 15 min before swimming are at risk of developing cutaneous disorders, especially at sites of injury, e.g. scars. PMID:7577833

  17. Chloroxyanion Residues in Cantaloupe and Tomatoes after Chlorine Dioxide Gas Sanitation.

    PubMed

    Smith, D J; Ernst, W; Herges, G R

    2015-11-01

    Chlorine dioxide gas is effective at cleansing fruits and vegetables of bacterial pathogens and(or) rot organisms, but little data are available on chemical residues remaining subsequent to chlorine gas treatment. Therefore, studies were conducted to quantify chlorate and perchlorate residues after tomato and cantaloupe treatment with chlorine dioxide gas. Treatments delivered 50 mg of chlorine dioxide gas per kg of tomato (2-h treatment) and 100 mg of gas per kg of cantaloupe (6-h treatment) in sealed, darkened containers. Chlorate residues in tomato and cantaloupe edible flesh homogenates were less than the LC-MS/MS limit of quantitation (60 and 30 ng/g respectively), but were 1319 ± 247 ng/g in rind + edible flesh of cantaloupe. Perchlorate residues in all fractions of chlorine dioxide-treated tomatoes and cantaloupe were not different (P > 0.05) than perchlorate residues in similar fractions of untreated tomatoes and cantaloupe. Data from this study suggest that chlorine dioxide sanitation of edible vegetables and melons can be conducted without the formation of unwanted residues in edible fractions. PMID:26496046

  18. Chemical kinetic modeling of chlorinated hydrocarbons under stirred-reactor conditions

    SciTech Connect

    Pitz, W.J.; Westbrook, C.K.

    1990-10-04

    The combustin of chloroethane is modeled as a stirred reactor so that we can study critical emission characteristics of the reactor as a function of residence time. We examine important operating conditions such as pressure, temperature, and equivalence ratio and their influence on destructive efficiency of chloroethane and production of other chlorinated products. The model uses a detailed chemical kinetic mechanism that we have developed previously for C{sub 3} hydrocarbons. We have added to this mechanism the chemical kinetic mechanism for C{sub 2} chlorinated hydrocarbons developed by Senkan and coworkers. Some reactions have been added to Senkan's mechanism and some of the reaction-rate expressions have been updated to reflect recent developments in the literature. In the modeling calculations, sensitivity coefficients are determined to find which reaction-rate constants have the largest effect on destructive efficiency. 25 refs., 6 figs., 1 tab.

  19. Radiation induced dechlorination of some chlorinated hydrocarbons in aqueous suspensions of various solid particles

    NASA Astrophysics Data System (ADS)

    Múčka, V.; Buňata, M.; Čuba, V.; Silber, R.; Juha, L.

    2015-07-01

    Radiation induced dechlorination of trichloroethylene (TCE) and tetrachloroethylene (PCE) in aqueous solutions containing the active carbon (AC) or cupric oxide (CuO) as the modifiers was studied. The obtained results were compared to the previously studied dechlorination of polychlorinated biphenyls (PCBs). Both modifiers were found to decrease the efficiency of dechlorination. The AC modifier acts mainly via adsorption of the aliphatic (unlike the aromatic) hydrocarbons and the CuO oxide mainly inhibits the mineralization of the perchloroethylene. The results presented in this paper will be also helpful for the studies of the impact of chlorinated hydrocarbons on the membrane permeability of living cells.

  20. Reduction of chlorinated hydrocarbons with natural sunlight in a platinum-catalyzed water photolysis system

    SciTech Connect

    Wang, T.C.; Tan, C.K.

    1988-08-01

    Carbon tetrachloride and trichloroethylene in a water photolysis system (Pt colloid/Ru(bipy)/sub 3//sup 2 +//MV/sup 2 +//EDTA) were reduced to methane and/or ethane during solar illumination. This paper demonstrates that solar energy can be used to excite electron-transfer reactions in the system, which results in the cleavage of water to H/sub 2/ and OH/sup -/. Data suggest chlorinated hydrocarbons added to the system can be dechlorinated and subsequently reduced to low molecular weight hydrocarbons.

  1. Using trees to remediate groundwaters contaminated with chlorinated hydrocarbons. 1997 annual progress report

    SciTech Connect

    Gordon, M.P.; Newman, L.A.; Strand, S.E.

    1997-01-01

    'Metabolism of Chlorinated Hydrocarbons Laboratory and field tests with poplar in tissue culture, bioreactors, and field sites have shown that, unlike bacteria, these plants are able to carry out complete degradation of fully chlorinated alkanes and alkenes to carbon dioxide and chloride. Carbon dioxide was produced as a product of the degradation of trichloroethylene (TCE), carbon tetrachloride (CT), and perchloroethylene (PCE) when axenic tissue cultures of poplar cells were exposed to radiolabelled compounds. The apparent degradation of PCE and CT, fully chlorinated hydrocarbons, in these aerobic plants is remarkable when contrasted to the lack of comparable aerobic degradation by bacteria. Oxidized metabolites, such as trichloroethanol, and di- and trichloroacetic acid, were detected in cell cultures exposed to TCE, suggesting the involvement of cytochrome P450s or other monooxygenase activities. Mass balance experiments with small poplar plants in laboratory reactors showed that significant TCE and CT was volatilized from the leaves, while a similar fraction of radiolabeled carbon from these chlorinated solvents was retained in the plant tissue.'

  2. TOXICITY OF RESIDUAL CHLORINE COMPOUNDS TO AQUATIC ORGANISMS

    EPA Science Inventory

    Laboratory studies on the acute and chronic toxicity of chlorine and inorganic chloramines to trout, salmon, minnows, bullhead, largemouth bass, and bluegill were conducted. Acute toxicity under continuous and intermittent patterns of exposure as well as behavioral, reproduction,...

  3. Membrane-Extraction Ion Mobility Spectrometry for In-Situ Detection of Chlorinated Hydrocarbons in Water

    SciTech Connect

    Du, Yongzhai; Zhang, Wei; Whitten, William B; Li, Haiyang; Watson, David B; Xu, Jun

    2010-01-01

    Membrane-extraction ion mobility spectrometry (ME-IMS) has been developed for in-situ sampling and analysis of trace chlorinated hydrocarbons in water in a single procedure. The sampling is configured so that aqueous contaminants permeate through a spiral hollow polydimethylsiloxane (PDMS) membrane and are carried away by a vapor flow through the membrane tube. The extracted analyte flows into an atmospheric pressure chemical ionization (APCI) chamber and is analyzed in a home-made IMS analyzer. PDMS membrane is found to effectively extract chlorinated hydrocarbon solvents from liquid phase to vapor. The specialized IMS analyzer has been found to have resolutions of R=33 and 41, respectively, for negative- and positive-modes and is capable of detecting aqueous tetrachloroethylene (PCE) and trichloroethylene (TCE) as low as 80 g/L and 74 g/L in negative ion mode, respectively. The time-dependent characteristics of sampling and detection of TCE are both experimentally and theoretically studied for various concentrations, membrane lengths, and flow rates. These characteristics demonstrate that membrane-extraction IMS is feasible for the continuous monitoring of chlorinated hydrocarbons in water.

  4. Enzyme-based detection of chlorinated hydrocarbons in water. Report for October 1982-July 1983

    SciTech Connect

    Offenhartz, B.H.; Lefko, J.L.

    1985-04-01

    An enzyme-based approach for detecting hazardous levels of high-molecular-weight chlorinated hydrocarbons in natural waters was explored. An extensive review of the literature indicated that the enzymes, lactate dehydrogenase, carbonic anhydrase, hexokinase, phosphorylase and an ATPase are suitable for field method development. Lactate dehydrogenase (LDH) was chosen to develop a method that promises rapid, reliable, and cost-effective detection. The LDH-catalyzed reaction is used to detect chlorinated hydrocarbons, which reduce the rate of the reaction by reversibly inhibiting the enzyme. The analysis uses pH detection and takes 5 minutes. So far, the LDH method has been used to detect aldrin, toxaphene, DDT, PCBs, pentachlorophenol and 2,4,5,-T at the parts per million level. A review of the literature suggests that most organochlorine pesticides, PCBs, polychlorinated phenols and chlorophenoxy derivatives can be detected by the LDH method. Preliminary investigations of potential interferants suggest that the LDH method selectively detects chlorinated hydrocarbons. Work was begun on immobilizing the enzyme for incorporation in water monitor and field detector designs. The LDH method shows potential for use in field devices and for processing extracts of soils and wastes, as well as water samples. These method adaptations are recommended for future work.

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

    USGS Publications Warehouse

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

    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.

  6. Natural attenuation of chlorinated hydrocarbons in a freshwater wetland

    USGS Publications Warehouse

    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.

  7. Eggshell thinning, chlorinated hydrocarbons, and mercury in inland aquatic bird eggs, 1969 and 1970

    USGS Publications Warehouse

    Faber, R.A.; Hickey, J.J.

    1973-01-01

    In the Upper Great Lakes States, 9 out of 13 species of fish-eating birds were found in 1969-70 to have sustained statistically significant decreases in eggshell thickness since 1946. Maximum changes in a thickness index occurred in great blue herons (-25%), red-breasted mergansers (-23%), common mergansers (-15%). and double-crested cormorants (-15%). Heron eggs taken in Louisiana generally displayed a smaller post-'46 change than herons in the Middle West. On a lipid basis, mean PCB- and DDE- residue levels exceeded 100 ppm in 7 out of 13 species in the Great Lakes States, and in 2 of 7 species in Louisiana, the average DDE: PCB ratios in the two regions being 1.25:1 and 3.9:1, respectively. Individual dieldrin values tended 10 be higher in Louisiana (31.6 and 13.95 ppm in heron species from two different locations), although values reached 10.1 and 9.4 ppm in great blue and black-crowned night herons in Wisconsin. BHC averaged 3.01 and 0.39 ppm in the Lake States and Louisiana, respectively. Of eggs examined for mercury. 29% had levels greater than 0.5 ppm, and 9% greater than 1.0 ppm on a wet-weight basis. Mercury levels in a small sample of eggs from Louisiana were consistently low. The differences in mercury levels between the two regions thus were similar to those found for the chlorinated hydrocarbons. While DDE was a prominent factor for most groups, especially herons, in relation to the eggshell thinning observed, dieldrin was also important to two groups even though DDE was present in much higher amounts. PCB's were also important to mergansers, while mercury was positively correlated with thickness index in grebes and negatively correlated in mergansers.

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

    PubMed

    Elliott, J E; Miller, M J; Wilson, L K

    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. PMID:15589662

  9. Determination of the Possible Source of Chlorinated Hydrocarbons Detected By SAM during MSL Mission

    NASA Astrophysics Data System (ADS)

    Buch, A.; Belmahdi, I.; Szopa, C.; Freissinet, C.; Glavin, D. P.; Francois, P.; Coll, P. J.; Miller, K.; Eigenbrode, J. L.; Stern, J. C.; Navarro-Gonzalez, R.; McAdam, A.; Teinturier, S.; Bonnet, J. Y.; Summons, R. E.; Millan, M.; Dequaire, T.; Cabane, M.; Mahaffy, P. R.

    2014-12-01

    The SAM GC-MS instrument on the Curiosity rover allows to analyze volatile compounds from the atmosphere or volatile compounds from the Martian regolith and refractory compounds in the regolith after sample treatment using wet chemistry. One portion of the wet chemistry experiment is composed of MTBSTFA (N-methyl-N-tert-butyldimethylsilyltrifluoroacetamide) / DMF (dimethylformamide). Abundant chlorinated hydrocarbons have been detected with SAM when analyzing samples collected in several sites explored by Curiosity rover. Some of these chlorohydrocarbons are produced during pyrolysis by the reaction of Martian oxychlorine compounds in the samples with terrestrial carbon from a derivatization agent (MTBSTFA) used in SAM (1, 2). Chlorobenzene cannot be formed by the direct reaction of MTBSTFA and DMF when heated in the presence of fused silica and perchlorates under SAM-like conditions (1)) therefore two other reaction pathways for chlorobenzene were proposed : (1) reactions between the volatile thermal degradation products of perchlorates (e.g. O2, Cl2 and HCl) and Tenax® and (2) the interaction of perchlorates with organic material from the martian regolith such as benzenecarboxylates (3, 4). This study investigates several propositions for chlorinated hydrocarbon formation by looking for: (1) all products coming from the interaction of Tenax® (which is part of the SAM hydrocarbon trap) and perchlorates, (2) also between some soil sample and perchlorates in the presence or absence of MTBSTFA and (c) sources of chlorinated hydrocarbon precursors. References: 1. D. P. Glavin et al.(2013) JGR 118, 1955-1973. 2. L. a Leshin et al. (2013) Science 341, 1238937. 3. C. Freissinet et al. (2014) LPSC XXXXV Abstract 2796. 4. D. Glavin et al. (2014) LPSC XXXV Abstract #1157.

  10. Stabile Chlorine Isotope Study of Martian Shergottites and Nakhlites; Whole Rock and Acid Leachates and Residues

    NASA Technical Reports Server (NTRS)

    Nakamura, N.; Nyquist, L. E.; Reese, Y.; Shih, C-Y; Fujitani, T.; Okano, O.

    2011-01-01

    We have established a precise analytical technique for stable chlorine isotope measurements of tiny planetary materials by TIMS (Thermal Ionization Mass Spectrometry) [1], for which the results are basically consistent with the IRMS tech-nique (gas source mass spectrometry) [2,3,4]. We present here results for Martian shergottites and nakhlites; whole rocks, HNO3-leachates and residues, and discuss the chlorine isotope evolution of planetary Mars.

  11. Assessment of biological effects of chlorinated hydrocarbons in osprey chicks

    USGS Publications Warehouse

    Elliott, J.E.; Wilson, L.K.; Henny, Charles J.; Trudeau, Suzanne F.; Leighton, Frederick A.; Kennedy, Sean W.; Cheng, Kimberly M.

    2001-01-01

    Osprey (Pandion haliaetus) eggs were collected during 1995 and 1996 at seven sites along the Fraser and Columbia River systems of British Columbia, Canada, and Washington and Oregon, USA. Fifty-four eggs were placed into a laboratory incubator. Thirty-eight of the hatched chicks were sacrificed within 24 h. Hatching success did not differ among sites and therefore between treatment and reference areas. Residual yolk sacs of eggs collected downstream of the large bleached-kraft pulp mill at Castlegar contained greater mean concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD, 2,930 ng/kg lipid) compared with reference sites such as the Nechako River, an upper tributary of the Fraser system (33.7 ng/kg). Total polychlorinated biphenyls (PCBs) in yolk sacs were also higher at Castlegar and in samples from the Columbia River downstream of Portland, Oregon, compared with those from the Nechako River. Concentrations of measured chemicals, including TCDD toxic equivalents (TEQs), total PCBs, p,pa??-dichlorodiphenylethylene (p,pa??-DDE), and other organochlorines were not different in eggs that failed to hatch compared with calculated whole-egg values for hatched eggs. There were significant biochemical responses; a hepatic cytochrome P4501A (CYP1A) cross-reactive protein was detected in all samples tested and correlated positively with ethoxyresorufin o-deethylase (EROD) activity and yolk sac concentrations of TEQs and total PCBs. Tissue concentrations of vitamin A compounds varied among sites and correlated positively with yolk sac concentrations of TEQs and PCBs. Morphological, histological, and other physiological parameters, including chick growth, edema, deformities, and hepatic and renal porphyrin concentrations, neither varied among sites nor showed concentration-related effects.

  12. Chlorine-hydrocarbon photochemistry in the marine troposphere and lower stratosphere

    NASA Technical Reports Server (NTRS)

    Singh, H. B.; Kasting, J. F.

    1988-01-01

    The role of chlorine atoms in the oxidation of methane and nonmethane hydrocarbons (NMHCs) in the marine troposphere and lower stratosphere was investigated using a one-dimensional photochemical model that incorporated the chemistry of CH4, NMHCs, NO(x), O(x), and HO(x), as well as organic and inorganic halogens in the troposphere and lower stratosphere. The model predicted that chlorine atoms are present in the marine troposphere at the concentrations of about 1000/cu cm, mostly as a product of the reaction between OH and HCl released from sea spray. The results indicate that Cl atoms cause 20 to 40 percent of NMHC oxidation in the troposphere and 40 to 90 percent in the lower stratosphere. At 15 km, the NMHC-Cl reactions account for nearly 80 percent of the PAN produced. Where available, experimental data confirmed the model predictions.

  13. Chloroxyanion residue quantification in cantaloupes treated with chlorine dioxide gas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous studies show that treatment of cantaloupes with chlorine dioxide (ClO2) gas at 5 mg/L for 10 minutes, results in a significant reduction (p<0.05) in initial microflora, an increase in shelf life without any alteration in color, and a 4.6 and 4.3 log reduction of E. coli O157:H7 and L. monoc...

  14. Natural attenuation of chlorinated solvents, petroleum hydrocarbons, and other organic compounds

    SciTech Connect

    Alleman, B.C.; Leeson, A.

    1999-11-01

    The natural attenuation option is getting more attention from site managers and regulators as a viable alternative to more costly engineered site remediation approaches. Natural attenuation was first demonstrated at sites with hydrocarbon contamination, but recent studies at sites contaminated by chlorinated compounds have shown that this approach often has merit for these more challenging contamination problems. Covering natural attenuation in media ranging from deep aquifers to shallow soils, and for contaminants ranging from fuels to solvents to herbicides, this volume offers the reader a comprehensive overview of case studies that represent the current state of the art in natural attenuation approaches to site remediation.

  15. Cl app: android-based application program for monitoring the residue chlorine in water

    NASA Astrophysics Data System (ADS)

    Intaravanne, Yuttana; Sumriddetchkajorn, Sarun; Porntheeraphat, Supanit; Chaitavon, Kosom; Vuttivong, Sirajit

    2015-07-01

    A farmer usually uses a cheap chemical material called chlorine to destroy the cell structure of unwanted organisms and remove some plant effluents in a baby shrimp farm. A color changing of the reaction between chlorine and chemical indicator is used to monitor the residue chlorine in water before releasing a baby shrimp into a pond. To get rid of the error in color reading, our previous works showed how a smartphone can be functioned as a color reader for estimating the chlorine concentration in water. In this paper, we show the improvement of interior configuration of our prototype and the distribution to several baby shrimp farms. In the future, we plan to make it available worldwide through the online market as well as to develop more application programs for monitoring other chemical substances.

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

    NASA Astrophysics Data System (ADS)

    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.

  17. Transport Modeling of Membrane Extraction of Chlorinated Hydrocarbon from Water for Ion Mobility Spectrometry

    SciTech Connect

    Zhang, Wei; Du, Yongzhai; Feng, Zhili; Xu, Jun

    2010-01-01

    Membrane-extraction Ion Mobility Spectrometry (ME-IMS) is a feasible technique for the continuous monitoring of chlorinated hydrocarbons in water. This work studies theoretically the time-dependent characteristics of sampling and detection of trichloroethylene (TCE). The sampling is configured so that aqueous contaminants permeate through a hollow polydimethylsiloxane (PDMS) membrane and are carried away by a transport gas flowing through the membrane tube into IMS analyzer. The theoretical study is based on a two-dimensional transient fluid flow and mass transport model. The model describes the TCE mixing in the water, permeation through the membrane layer, and convective diffusion in the air flow inside membrane tube. The effect of various transport gas flow rates on temporal profiles of IMS signal intensity is investigated. The results show that fast time response and high transport yield can be achieved for ME-IMS by controlling the flow rate in the extraction membrane tube. These modeled time-response profiles are important for determining duty cycles of field-deployable sensors for monitoring chlorinated hydrocarbons in water.

  18. Determination of Chlorinated Hydrocarbons in Water Using Highly Sensitive Mid-Infrared Sensor Technology

    PubMed Central

    Lu, Rui; Mizaikoff, Boris; Li, Wen-Wei; Qian, Chen; Katzir, Abraham; Raichlin, Yosef; Sheng, Guo-Ping; Yu, Han-Qing

    2013-01-01

    Chlorinated aliphatic hydrocarbons and chlorinated aromatic hydrocarbons (CHCs) are toxic and carcinogenic contaminants commonly found in environmental samples, and efficient online detection of these contaminants is still challenging at the present stage. Here, we report an advanced Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR) sensor for in-situ and simultaneous detection of multiple CHCs, including monochlorobenzene, 1,2-dichlorobenzene, 1,3-dichlorobenzene, trichloroethylene, perchloroethylene, and chloroform. The polycrystalline silver halide sensor fiber had a unique integrated planar-cylindric geometry, and was coated with an ethylene/propylene copolymer membrane to act as a solid phase extractor, which greatly amplified the analytical signal and contributed to a higher detection sensitivity compared to the previously reported sensors. This system exhibited a high detection sensitivity towards the CHCs mixture at a wide concentration range of 5~700 ppb. The FTIR-ATR sensor described in this study has a high potential to be utilized as a trace-sensitive on-line device for water contamination monitoring. PMID:23982222

  19. USING REDUCING AGENTS TO ELIMINATE CHLORINE DIOXIDE AND CHLORITE ION RESIDUALS IN DRINKING WATER

    EPA Science Inventory

    In an effort to determine the viability of various disinfection alternatives, the Evansville, Ind. Water and Sewer Utility is engaged in a pilot-plant investigation to compare chlorine dioxide and ozone pretreatment. As a result of increased speculation that the total residual c...

  20. ANALYSIS FOR OZONE AND RESIDUAL CHLORINE BY DIFFERENTIAL PULSE POLAROGRAPHY OF PHENYLARSINE OXIDE

    EPA Science Inventory

    The differential pulse polarography of phenylarsine oxide (C6H5AsO) as an indirect determination of ozone and residual chlorine is investigated. This procedure is compared with the standard methods of analysis for these oxidants in water and wastewater. The limit of detection for...

  1. Determination of the Sources of Chlorinated Hydrocarbons Detected During MSL Missions

    NASA Astrophysics Data System (ADS)

    Buch, Arnaud; Belmahdi, Imène; Szopa, Cyril; Freissinet, Caroline; Glavin, Danny P.; Miller, Kirsten; Summons, Roger; Francois, Pascaline; Coll, Patrice; Eigenbrode, Jennifer; Teinturier, Samuel; Navarro-Gonzalez, Rafael; Stern, Jennifer; McAdam, Amy; Dequaire, Tristan; Millan, Maeva; Bonnet, Jean Yves; Coscia, David; Cabane, Michel; Mahaffy, Paul

    2015-04-01

    Sample Analysis at Mars (SAM) is one of the instruments of the MSL mission. Three analytical instruments composed SAM: the Tunable Laser Spectrometer (TLS), the Gas Chromatography (GC) and the Mass Spectrometer (QMS). It includes a sample preparation and gas processing system implemented with a pyrolysis system, wet chemistry (MTBSTFA and TMAH) and the hydrocarbon trap (silica beads, Tenax® TA and Carbosieve G), employed to concentrate volatiles released from the sample prior to GC-MS analysis [1]. This study investigates several propositions for chlorinated hydrocarbon formation, detected by SAM. Here we report on the detection of chlorohydrocarbon compounds and their potential origin. To date, SAM has detected a range of diverse chlorinated hydrocarbons from GCMS analysis of samples collected at the several locations explored by Curiosity (Rocknest, John Klein, Cumberland and Confidence Hill). Some of these chlorohydrocarbons are produced during pyrolysis by the reaction of Martian oxychlorine compounds in the samples with terrestrial carbon from a derivatization agent (MTBSTFA) present in SAM [2, 3]. Chlorobenzene cannot be formed by the reaction of MTBSTFA and perchlorates (2) and two other reaction pathways were therefore proposed : (i) reactions between the volatile thermal degradation products of perchlorates (e.g. O2, Cl2 and HCl) and Tenax® and (ii) the interaction of perchlorates (T > 200 °C) with OM from Martian soil such as benzenecarboxylates [4, 5]. References: 1. P. R. Mahaffy et al. (2012) Space Sci. Rev. 170, 401-478. 2. D. P. Glavin et al.(2013) JGR 118, 1955-1973. 3. L. a Leshin et al. (2013) Science 341, 1238937. 4. C. Freissinet et al. (2014) LPSC XXXXV Abstract 2796. 5. H. Steininger et al. (2012) Planet. Space Sci. 71, 9-17.

  2. Chlorinated pesticide residues in sediments from the Arabian Sea along the central west coast of India

    SciTech Connect

    Sarkar, A.; Gupta, R.S.

    1987-12-01

    The problem of environmental contamination by persistent chlorinated pesticides still evokes major concern due to the presence of their residues in the environment and in human tissues. In developing countries like India organochlorine insecticides, especially DDT are extensively being used in agriculture and vector control programs. Few data are available on their levels of concentration from the seas around India. Persistent pesticides residues can be expected to accumulate in marine sediments. However, very little data on this are available along the Indian coast. An attempt has been made in the present communication to identify and quantify some of the chlorinated pesticides residues in the marine sediments collected from different region along the central west coast of India. This is a part of our ongoing project to monitor and map pollutants within the exclusive economic zone of India.

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

    SciTech Connect

    Bost, R.C.; Perry, R.G.; Barber, T.

    1997-06-01

    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.

  4. PERMEABLE REACTIVE SUBSURFACE BARRIERS FOR THE INTERCEPTION AND REMEDIATION OF CHLORINATED HYDROCARBON AND CHROMIUM (VI) PLUMES IN GROUND WATER

    EPA Science Inventory

    This document concerns the use of permeable reactive subsurface barriers for the remediation of plumes of chlorinated hydrocarbons and Cr(VI) species in ground water, using zero-valent iron (Fe0) as the reactive substrate. Such systems have undergone thorough laboratory research,...

  5. MONITORING THE SUCCESS OF SEDIMENT REMEDIATION AT A SITE CONTAMINATED WITH CHLORINATED PESTICIDES, POLYNUCLEAR AROMATIC HYDROCARBONS AND ARSENIC

    EPA Science Inventory

    Monitoring the Success of Sediment Remediation at a Site Contaminated with Chlorinated Pesticides, Polynuclear Aromatic Hydrocarbons and Arsenic (Baird & McGuire Superfund Site, Holbrook, MA) Contaminated sediment in the Cochato River adjacent to the Baird & McGuire Superfund Sit...

  6. Toxic effects of residual chlorine on larvae of Hydropsyche pellucidula (Trichoptera, Hydropsychidae): A proposal of biological indicator

    SciTech Connect

    Camargo, J.A. )

    1991-08-01

    Elemental chlorine (Cl{sub 2}) and other chlorine compounds, such as chloramines and hypochlorites, have been used as important bactericides in disinfection of drinking waters for many years. Residual chlorine concentrations in municipal water supplies are normally between 0.5 and 2 mg/L. In water at pH values above 5, elemental chlorine and hypochlorite compounds react rapidly, resulting in the formation of hypochlorous acid (HOCl) in equilibrium with hypochlorite ions (OCL-). Very little is known about the toxicity of residual chlorine on aquatic insects that comprise the macroinvertebrate communities of freshwater ecosystems. This study examines the toxic effects of municipal chlorinated waters on larvae of Hydropsyche pellucidula (Curtis), a common insect species in macrobenthic communities of rivers and streams in the Iberian Peninsula and other European countries, evaluating implications on their life cycles. Field and laboratory studies were performed in order to reach these goals.

  7. Evidence for perchlorates and the origin of chlorinated hydrocarbons detected by SAM at the Rocknest aeolian deposit in Gale Crater

    NASA Astrophysics Data System (ADS)

    Glavin, Daniel P.; Freissinet, Caroline; Miller, Kristen E.; Eigenbrode, Jennifer L.; Brunner, Anna E.; Buch, Arnaud; Sutter, Brad; Archer, P. Douglas; Atreya, Sushil K.; Brinckerhoff, William B.; Cabane, Michel; Coll, Patrice; Conrad, Pamela G.; Coscia, David; Dworkin, Jason P.; Franz, Heather B.; Grotzinger, John P.; Leshin, Laurie A.; Martin, Mildred G.; McKay, Christopher; Ming, Douglas W.; Navarro-González, Rafael; Pavlov, Alexander; Steele, Andrew; Summons, Roger E.; Szopa, Cyril; Teinturier, Samuel; Mahaffy, Paul R.

    2013-10-01

    A single scoop of the Rocknest aeolian deposit was sieved (< 150 µm), and four separate sample portions, each with a mass of ~50 mg, were delivered to individual cups inside the Sample Analysis at Mars (SAM) instrument by the Mars Science Laboratory rover's sample acquisition system. The samples were analyzed separately by the SAM pyrolysis evolved gas and gas chromatograph mass spectrometer analysis modes. Several chlorinated hydrocarbons including chloromethane, dichloromethane, trichloromethane, a chloromethylpropene, and chlorobenzene were identified by SAM above background levels with abundances of ~0.01 to 2.3 nmol. The evolution of the chloromethanes observed during pyrolysis is coincident with the increase in O2 released from the Rocknest sample and the decomposition of a product of N-methyl-N-(tert-butyldimethylsilyl)-trifluoroacetamide (MTBSTFA), a chemical whose vapors were released from a derivatization cup inside SAM. The best candidate for the oxychlorine compounds in Rocknest is a hydrated calcium perchlorate (Ca(ClO4)2·nH2O), based on the temperature release of O2 that correlates with the release of the chlorinated hydrocarbons measured by SAM, although other chlorine-bearing phases are being considered. Laboratory analog experiments suggest that the reaction of Martian chlorine from perchlorate decomposition with terrestrial organic carbon from MTBSTFA during pyrolysis can explain the presence of three chloromethanes and a chloromethylpropene detected by SAM. Chlorobenzene may be attributed to reactions of Martian chlorine released during pyrolysis with terrestrial benzene or toluene derived from 2,6-diphenylphenylene oxide (Tenax) on the SAM hydrocarbon trap. At this time we do not have definitive evidence to support a nonterrestrial carbon source for these chlorinated hydrocarbons, nor do we exclude the possibility that future SAM analyses will reveal the presence of organic compounds native to the Martian regolith.

  8. Evidence for Perchlorates and the Origin of Chlorinated Hydrocarbons Detected by SAM at the Rocknest Aeolian Deposit in Gale Crater

    NASA Technical Reports Server (NTRS)

    Glavin, Daniel P.; Freissinet, Caroline; Miller, Kristen E.; Eigenbrode, Jennifer L.; Brunner, Anna E.; Buch, Arnaud; Sutter, Brad; Archer, P. Douglas, Jr.; Atreya, Sushil K.; Brinckerhoff, William B.; Cabane, Michel; Coll, Patrice; Conrad, Pamela G.; Coscia, David; Dworkin, Jason P.; Franz, Heather B.; Grotzinger, John P.; Leshin, Laurie A.; Martin, Mildred G.; McKay, Christopher; Ming, Douglas W.; Navarro-Gonzalez, Rafael; Pavlov, Alexander; Steele, Andrew; Summons, Roger E.; Szopa, Cyril; Teinturier, Samuel; Mahaffy, Paul R.

    2013-01-01

    A single scoop of the Rocknest aeolian deposit was sieved (less than 150 micrometers), and four separate sample portions, each with a mass of approximately 50 mg, were delivered to individual cups inside the Sample Analysis at Mars (SAM) instrument by the Mars Science Laboratory rover's sample acquisition system. The samples were analyzed separately by the SAM pyrolysis evolved gas and gas chromatograph mass spectrometer analysis modes. Several chlorinated hydrocarbons including chloromethane, dichloromethane, trichloromethane, a chloromethylpropene, and chlorobenzene were identified by SAM above background levels with abundances of approximately 0.01 to 2.3 nmol. The evolution of the chloromethanes observed during pyrolysis is coincident with the increase in O2 released from the Rocknest sample and the decomposition of a product of N-methyl-N-(tert-butyldimethylsilyl)-trifluoroacetamide (MTBSTFA), a chemical whose vapors were released from a derivatization cup inside SAM. The best candidate for the oxychlorine compounds in Rocknest is a hydrated calcium perchlorate (Ca(ClO4)2·nH2O), based on the temperature release of O2 that correlates with the release of the chlorinated hydrocarbons measured by SAM, although other chlorine-bearing phases are being considered. Laboratory analog experiments suggest that the reaction of Martian chlorine from perchlorate decomposition with terrestrial organic carbon from MTBSTFA during pyrolysis can explain the presence of three chloromethanes and a chloromethylpropene detected by SAM. Chlorobenzene may be attributed to reactions of Martian chlorine released during pyrolysis with terrestrial benzene or toluene derived from 2,6-diphenylphenylene oxide (Tenax) on the SAM hydrocarbon trap. At this time we do not have definitive evidence to support a nonterrestrial carbon source for these chlorinated hydrocarbons, nor do we exclude the possibility that future SAM analyses will reveal the presence of organic compounds native to the

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

    SciTech Connect

    Strand, Stuart E.

    2002-06-01

    Several varieties of transgenic poplar containing cytochrome P-450 2E1 have been constructed and are undergoing tests. Strategies for improving public acceptance and safety of transgenic poplar for chlorinated hydrocarbon phytoremediation are being developed. We have discovered a unique rhizobium species that lives within the stems of poplar and we are investigating whether this bacterium contributes nitrogen fixed from the air to the plant and whether this endophyte could be used to introduce genes into poplar. Studies of the production of chloride ion from TCE have shown that our present P-450 constructs did not produce chloride more rapidly than wild type plants. Follow-up studies will determine if there are other rate limiting downstream steps in TCE metabolism in plants. Studies of the metabolism of carbon tetrachloride in poplar cells have provided evidence that the native plant metabolism is due to the activity of oxidative enzymes similar to the mammalian cytochrome P-450 2E1.

  10. Role of plant biomass in the global environmental partitioning of chlorinated hydrocarbons

    SciTech Connect

    Calamari, D.; Morosini, M.; Vighi, M. ); Bacci, E.; Focardi, S.; Gaggi, C. )

    1991-08-01

    Plant biomass plays a significant role in the global environmental partitioning phenomena and plants are good indicators of tropospheric contamination levels by chlorinated hydrocarbons. In the present research 300 samples of plants were collected in 265 areas distributed worldwide and analyzed for HCB (hexachlorobenzene), {alpha}-HCH (hexachlorocyclohexane), {gamma}-HCH, p,p{prime}-DDT,o,p{prime}-DDT, and p,p{prime}-DDE (degradation product of DDT). Global HCB distribution is strongly dependent on the temperature, the HCB being present mainly in samples from cold areas. The sum of DDTs show higher concentrations in samples from topical areas, while the sum of HCHs is higher in the plants from the Northern Hemisphere. These results are discussed, taking into account the role of physicochemical properties in determining the global distribution as well as the air age of the contamination.

  11. Chlorine

    ERIC Educational Resources Information Center

    Young, Jay A.

    2004-01-01

    A chemical laboratory information profile (CLIP) of the chemical chlorine, produced in small quantities in the laboratory, is presented. The profile summarizes physical and harmful properties, exposure limits, reactivity risks, and symptoms of major exposure for the benefit of teachers and students using the chemical in the laboratory.

  12. Chlorine

    Integrated Risk Information System (IRIS)

    Chlorine ; CASRN 7782 - 50 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effects

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

    PubMed

    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 < 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. PMID:22783624

  14. Comparative bioaccumulation of chlorinated hydrocarbons from sediment by two infaunal invertebrates

    SciTech Connect

    Meador, J.P.; Adams, N.G.; Casillas, E.; Bolton, J.L.

    1995-12-31

    Bioaccumulation of chlorinated hydrocarbons (CHs) from field-contaminated sediments by two infaunal invertebrates, Rhepoxynius abronius and Armandia brevis was examined in the laboratory. Sediments were selected over a large geographical area of an urban estuary, the Hudson-Raritan, to assess the potential for bioaccumulation. Amphipod and polychaete tissue burdens were highly correlated over sites; however, concentrations of the trichlorobiphenyls in the polychaete were about twice that found in the amphipod and 4 to 8 times higher for the more hydrophobic PCBs. Unlike PAHs from these sediments, concentrations of CHs in IW and sediment indicated that partition coefficients (K{sub oc}) were generally as predicted. K{sub oc} values determined with non-sorbed interstitial water concentrations (IW{sub free}) were much closer to predicted values compared to those based on the total chlorinated compound. As expected, BAF values were highly variable among sites and increased greatly with declining TOC content. The BAF{sub loc} (lipid/organic carbon normalized bioaccumulation factor) for trichlorobiphenyls in the polychaete was similar to that for the amphipod; however the polychaete BAF{sub loc} increased with increasing hydrophobicity and was maximum for the pentachlorobiphenyls and close to the expected maximum. Some evidence for site-specific BAF{sub loc} values was found because of a strong correlation between BAF{sub loc} and sediment concentration; however for some PCBs, this correlation was weak.

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

    SciTech Connect

    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.

  16. Inactivation of hepatitis A virus and indicator organisms in water by free chlorine residuals.

    PubMed Central

    Grabow, W O; Gauss-Müller, V; Prozesky, O W; Deinhardt, F

    1983-01-01

    Hepatitis A virus (HAV) and selected indicator organisms were mixed together in chlorine-demand-free buffers at pH 6, 8, or 10 and exposed to free chlorine residuals, and the survival kinetics of individual organisms were compared. HAV was enumerated by a most-probable-number dilution assay, using PLC/PRF/5 liver cells for propagation of the virus and radioimmunoassay for its detection. At all pH levels, HAV was more sensitive than Mycobacterium fortuitum, coliphage V1 (representing a type of phage common in some sewage-polluted waters), and poliovirus type 2. Under certain conditions, HAV was more resistant than Escherichia coli, Streptococcus faecalis, coliphage MS2, and reovirus type 3. It was always more resistant than SA-11 rotavirus. Evidence is presented that conditions generally specified for the chlorine disinfection of drinking-water supplies will also successfully inactivate HAV and that HAV inactivation by free chlorine residuals can reliably be monitored by practical indicator systems consisting of appropriate combinations of suitable indicators such as coliform and acid-fast bacteria, coliphages, the standard plate count, and fecal streptococci. PMID:6314894

  17. Relative induction of a biomarker, P450 RGS, by PAHs and chlorinated hydrocarbons

    SciTech Connect

    Bothner, K.; Anderson, J. |

    1995-12-31

    A reporter gene system (RGS) assay has been engineered from a human liver cancer cell fine so that the induction of CPA gene will result in the production of luciferase (firefly plasmid) instead of cytochrome P450. Induction of this test system by compounds such as polycyclic aromatic hydrocarbons (PAHs) and chlorinated hydrocarbons infers these xenobiotics are present at levels that are potentially toxic, carcinogenic, or mutagenic to organisms. Six well plates with 1.0 {times} 10{sup 6} adhered cells in 2 mLs of media are inoculated with varying volumes of organic solvents containing a reference toxicant (TCDD) and sample extracts. Solvent extracts (EPA 3540) of aquatic sediments, soils, and mussel tissue have been applied directly to this system. Test results show a significant RGS induction from concentrations of PAHs, that if present in a 40 gram sediment sample, would be (in ng/g or ppb): 20 for dibenz(a,h)anthracene; 70 for benz(a)anthracene; 100 for benzo(a)pyrene; and 250 for chrysene. Testing with mixtures of PAHs and environmental samples has shown that levels of 300 to 400 ppb are detected. Results to be presented from P450 RGS testing will show that the estimated health risk (Toxic Equivalent Factors, TEFs) of some of the PAHs may be as great or greater than some of the coplanar PCB.

  18. Chlorine

    SciTech Connect

    Talmage, Sylvia Smith

    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

  19. The effect of fuel and chlorinated hydrocarbons on a vapor phase carbon adsorption system

    SciTech Connect

    Crawford, W.J.; Cheney, J.L.; Taggart, D.B.

    1995-12-31

    A soil vapor extraction (SVE) system installed at the South Tacoma Well 12A Superfund Site was designed to recover 1,2-dichloroethylene (DCE), trichloroethylene (TCE), tetrachloroethylene (PCE), and 1,1,2,2-tetrachloroethane (1,1,2,2-TCA) from the vadose zone. The basic system consisted of twenty-two extraction wells, three centrifugal blowers, and three carbon adsorbers. The carbon adsorbers were regenerated on site by steam stripping. The mixture of steam and stripped organics was condensed and then decanted to separate the water from the organic phase. The recovered water was air stripped to remove the dissolved organics prior to discharge to the city storm sewer. The recovered organic phase was then shipped off site for thermal destruction. Previous reports described operating difficulties with the decanter, and air strippers. Sampling and analyses were performed which identified the problem as the simultaneous recovery of unexpected fuel hydrocarbons in addition to the solvents. Recovery of fuels resulted in a light phase in the decanter in addition to the water and heavy solvent phases. This required redesign of the decanter to handle the third phase. The effectiveness of desorption of the carbon beds by steam stripping gradually decreased as the remediation progressed into the second year of operation. Samples were collected from the carbon beds to evaluate the effect of the fuel and chlorinated hydrocarbons on the activated carbon. This report describes the results of these analyses. The data indicated that both 1,1,2,2-TCA and fuel hydrocarbons in the C-9 to C-24 range remained in the carbon beds after steam regeneration in sufficient quantities to require replacing the carbon.

  20. Effect of bioremediation on polycyclic aromatic hydrocarbon residues in soil

    SciTech Connect

    Wang, Xiaoping; Yu, Xiaobing; Bartha, R. )

    1990-07-01

    Soil contamination (60 mg/g of soil) by a diesel oil (DO) spill was simulated in outdoor lysimeter units and the effect of bioremediation treatment consisting of liming, fertilization, and tilling on the persistence of polycyclic aromatic hydrocarbon (PAH) components of DO was measured. After solvent extraction from soil and class separation on silica gel, PAH components were identified and partially quantified by GC-ITD analysis. Residual mutagenicity and acute toxicity of the contaminated soil was also assessed by Ames and Microtox tests. Bioremediation treatment, while increasing the rate of total hydrocarbon degradation, had an even greater effect on PAH persistence, almost completely eliminating these compounds in 12 weeks. Without bioremediation, 12.5-32.5% of the higher molecular weight PAH were still present at 12 weeks. Mutagenicity and toxicity tests corroborated the above results. After substantial initial mutagenicity and toxicity, the contaminated soil approached the background level of uncontaminated soil after 12 weeks of bioremediation. Detoxification was complete in 20 weeks.

  1. An assessment of natural biotransformation of petroleum hydrocarbons and chlorinated solvents at an aquifer plume transect.

    PubMed

    Skubal, K L; Barcelona, M J; Adriaens, P

    2001-05-01

    Field biogeochemical characterization and laboratory microcosm studies were performed to assess the potential for future biotransformation of trichloroethylene (TCE) and toluene in a plume containing petroleum hydrocarbons and chlorinated solvents at the former Wurtsmith Air Force Base in Oscoda, MI. In situ terminal electron accepting processes (TEAPs), contaminant composition and microbial phylogeny were studied at a plume transect 100 m downgradient of the source. The presence of reduced electron acceptors, relevant microbial communities, and elevated dissolved methane and carbon dioxide concentrations at the transect, as well as downgradient accumulation of BTEX metabolites and dechlorination products, indicated that past or current reductive dechlorination at the transect was likely driven by BTEX biodegradation in the methanogenic zone. However, TCE and toluene mineralization in sediment-groundwater microcosms without added electron acceptors did not exceed 5% during 300 days of incubation and was nearly invariant with original sediment TEAP, even following amendments of nitrogen and phosphorus. Mineralization rates were on the order of 0.0015-0.03 mumol/g day. After 8 months, microcosms showed evidence of methanogenesis, but CH4 and CO2 production arose from the degradation of contaminants other than toluene. Cis-dichloroethylene was observed in only one methanogenic microcosm after more than 500 days. It appears likely that spatially and temporally dynamic redox zonation at the plume transect will prevent future sustained reductive dehalogenation of highly chlorinated solvents, for during the course of a year, the predominant TEAP at the highly contaminated water table shifted from methanogenesis to iron- and sulfate-reduction. It is recommended that biotransformation studies combine considerations of long-term, spatially relevant changes in redox zonation with laboratory-scale studies of electron donor utilization and cometabolic substrate transformation

  2. Diurnal variability of chlorinated polycyclic aromatic hydrocarbons in urban air, Japan

    NASA Astrophysics Data System (ADS)

    Ohura, Takeshi; Horii, Yuichi; Kojima, Mitsuhiro; Kamiya, Yuta

    2013-12-01

    Concentrations of 3- to 5-ring chlorinated polycyclic aromatic hydrocarbons (ClPAHs) and corresponding PAHs were quantified in 3-h integrated air samples, taken serially over 3-day periods in December 2009 (winter) and August 2010 (summer) in the urban area of Shizuoka, Japan. Twenty species of targeted ClPAHs were detected in both gas and particle phases throughout each campaign. Mean concentrations of total ClPAHs in the winter and summer campaigns were 133 ± 53 pg m-3 and 32 ± 27 pg m-3, respectively. Throughout the campaigns, diurnal variations of total ClPAHs concentrations did not have periodic fluctuation such as decreasing in daytime and increasing in nighttime, observed in PAHs. However, the mean concentrations of particulate ClPAHs trended to be slightly higher in nighttime than in daytime, but not for gaseous ClPAHs. Significant correlations were observed between the concentrations of total ClPAHs and total PAHs in particulate phase, but not in gaseous phase. In addition, for particulate phase, there were significant correlations between the concentrations of individual ClPAHs and corresponding parent PAHs, nitrate, and chlorine in summer, but not in winter. Considering these behaviors of ClPAHs in the air, the emission sources could have features of as follows: (i) specific emission sources emitted both ClPAHs and PAHs in particulate phase could be present in the area; (ii) particulate ClPAHs could be more strongly influenced by local sources and photochemical reactions rather than by transboundary air pollution; (iii) the possible sources could be combustion processes included biomass and fossil fuels.

  3. 40 CFR 180.526 - Synthetic isoparaffinic petroleum hydrocarbons; tolerances for residues.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... residues. (a) General. Synthetic isoparaffinic petroleum hydrocarbons complying with 21 CFR 172.882 (a) and... 40 CFR part 180 and in this part. (b) Section 18 emergency exemptions. (c) Tolerances with regional... hydrocarbons; tolerances for residues. 180.526 Section 180.526 Protection of Environment...

  4. 40 CFR 180.526 - Synthetic isoparaffinic petroleum hydrocarbons; tolerances for residues.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... residues. (a) General. Synthetic isoparaffinic petroleum hydrocarbons complying with 21 CFR 172.882 (a) and... 40 CFR part 180 and in this part. (b) Section 18 emergency exemptions. (c) Tolerances with regional... hydrocarbons; tolerances for residues. 180.526 Section 180.526 Protection of Environment...

  5. 40 CFR 180.526 - Synthetic isoparaffinic petroleum hydrocarbons; tolerances for residues.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... residues. (a) General. Synthetic isoparaffinic petroleum hydrocarbons complying with 21 CFR 172.882 (a) and... 40 CFR part 180 and in this part. (b) Section 18 emergency exemptions. (c) Tolerances with regional... hydrocarbons; tolerances for residues. 180.526 Section 180.526 Protection of Environment...

  6. 40 CFR 180.526 - Synthetic isoparaffinic petroleum hydrocarbons; tolerances for residues.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... residues. (a) General. Synthetic isoparaffinic petroleum hydrocarbons complying with 21 CFR 172.882 (a) and... 40 CFR part 180 and in this part. (b) Section 18 emergency exemptions. (c) Tolerances with regional... hydrocarbons; tolerances for residues. 180.526 Section 180.526 Protection of Environment...

  7. 40 CFR 180.526 - Synthetic isoparaffinic petroleum hydrocarbons; tolerances for residues.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... residues. (a) General. Synthetic isoparaffinic petroleum hydrocarbons complying with 21 CFR 172.882 (a) and... 40 CFR part 180 and in this part. (b) Section 18 emergency exemptions. (c) Tolerances with regional... hydrocarbons; tolerances for residues. 180.526 Section 180.526 Protection of Environment...

  8. BENZENE AND NAPHTHALENE SORPTION ON SOIL CONTAMINATED WITH HIGH MOLECULAR WEIGHT RESIDUAL HYDROCARBONS FROM UNLEADED GASOLINE

    EPA Science Inventory

    For complex nonaqueous phase liquids (NAPLs), the composition of the NAPL retained in the pore space of geologic material weathers until the residual NAPL no longer acts a liquid and exists as discrete regions of hydrocarbon (termed residual hydrocarbons) in association with the ...

  9. INTERNATIONAL STUDY OF 'ARTEMIA' VIII. COMPARISON OF THE CHLORINATED HYDROCARBONS AND HEAVY METALS IN FIVE DIFFERENT STRAINS OF NEWLY HATCHED 'ARTEMIA' AND A LABORATORY-REARED MARINE FISH

    EPA Science Inventory

    Newly hatched nauplii of Artemia from Brazil, Australia, Italy, and the United States (Utah and San Pablo Bay, California) were analyzed for chlorinated hydrocarbons. The Brazil and Australia nauplii contained very low levels of PCB and chlorinated insecticides. Italian nauplii c...

  10. Biosynthetic Chlorination of the Piperazate Residue in Kutzneride Biosynthesis by KthP

    PubMed Central

    2011-01-01

    Kutznerides 2 and 8 of the cyclic hexadepsipeptide family of antifungal natural products from the soil actinomycete Kutzneria sp. 744 contain two sets of chlorinated residues, a 6,7-dichlorohexahydropyrroloindole moiety derived from dichlorotryptophan and a 5-chloropiperazate moiety, as well as a methylcyclopropylglycine residue that may arise from isoleucine via a cryptic chlorination pathway. Previous studies identified KtzD, KtzQ, and KtzR as three halogenases in the kutzneride pathway but left no candidate for installing the C5 chlorine on piperazate. On the basis of analysis of the complete genome sequence of Kutzneria, we now identify a fourth halogenase in the pathway whose gene is separated from the defined kutzneride cluster by 12 open reading frames. KthP (kutzneride halogenase for piperazate) is a mononuclear nonheme iron halogenase that acts on the piperazyl ring tethered by a thioester linkage to the holo forms of thiolation domains. MS analysis of the protein-bound product confirmed chlorination of the piperazate framework from the (3S)- but not the (3R)-piperazyl-S-pantetheinyl thiolation proteins. After thioesterase-mediated release, nuclear magnetic resonance was used to assign the free imino acid as (3S,5S)-5-chloropiperazate, distinct from the 3S,5R stereoisomer reported in the mature kutznerides. These results demonstrate that a fourth halogenase, KthP, is active in the kutzneride biosynthetic pathway and suggest further processing of the (3S,5S)-5-chloropiperazate during subsequent incorporation into the kutzneride depsipeptide frameworks. PMID:21648411

  11. Biosynthetic chlorination of the piperazate residue in kutzneride biosynthesis by KthP.

    PubMed

    Jiang, Wei; Heemstra, John R; Forseth, Ry R; Neumann, Christopher S; Manaviazar, Soraya; Schroeder, Frank C; Hale, Karl J; Walsh, Christopher T

    2011-07-12

    Kutznerides 2 and 8 of the cyclic hexadepsipeptide family of antifungal natural products from the soil actinomycete Kutzneria sp. 744 contain two sets of chlorinated residues, a 6,7-dichlorohexahydropyrroloindole moiety derived from dichlorotryptophan and a 5-chloropiperazate moiety, as well as a methylcyclopropylglycine residue that may arise from isoleucine via a cryptic chlorination pathway. Previous studies identified KtzD, KtzQ, and KtzR as three halogenases in the kutzneride pathway but left no candidate for installing the C5 chlorine on piperazate. On the basis of analysis of the complete genome sequence of Kutzneria, we now identify a fourth halogenase in the pathway whose gene is separated from the defined kutzneride cluster by 12 open reading frames. KthP (kutzneride halogenase for piperazate) is a mononuclear nonheme iron halogenase that acts on the piperazyl ring tethered by a thioester linkage to the holo forms of thiolation domains. MS analysis of the protein-bound product confirmed chlorination of the piperazate framework from the (3S)- but not the (3R)-piperazyl-S-pantetheinyl thiolation proteins. After thioesterase-mediated release, nuclear magnetic resonance was used to assign the free imino acid as (3S,5S)-5-chloropiperazate, distinct from the 3S,5R stereoisomer reported in the mature kutznerides. These results demonstrate that a fourth halogenase, KthP, is active in the kutzneride biosynthetic pathway and suggest further processing of the (3S,5S)-5-chloropiperazate during subsequent incorporation into the kutzneride depsipeptide frameworks. PMID:21648411

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

    USGS Publications Warehouse

    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

  13. Strain construction strategies for chlorinated aromatic hydrocarbon-utilizers by multiple chemostat

    SciTech Connect

    Huang, C.M.

    1988-01-01

    A multiple chemostat method was used for the construction of a recombinant bacterium having the ability to degrade chlorinated aromatic hydrocarbons (CAH). This method permits natural genetic exchange between two parental strains and subsequent selection of a novel catabolic genotype in a defined system. Many recombinants which could utilize chlorobenzene (CB) as a sole source of carbon were constructed from several separate experiments in less than one month. Reproducibility is related to several important factors such as dilution rate, growth substrate, and surface attachment. A recombinant strain, Acinetobacter sp. CB15, which could grown on 3-chlorobiphenyl (PCB congener) with the release of inorganic chloride, was constructed by the application of the multiple chemostat method. This represents the first report of a pure culture able to grow on 3-chlorobiphenyl with the release of inorganic chloride. Two metabolites produced by Acinetobacter sp. CB15 grown on 3-chlorobiphenyl were identified as 3-chlorobenzoic acid and 3-chlorocatechol. An unidentified, dead-end, black metabolite with a UV absorption maximum at 255 nm was also produced. Recombinant strain CB15 could also cometabolize, 3,3{prime}-dichlorobiphenyl with the release of inorganic chloride when it was grown on biphenyl as the growth substrate.

  14. Gas- and Particle-Phase Products from the Chlorine-Initiated Oxidation of Polycyclic Aromatic Hydrocarbons.

    PubMed

    Riva, Matthieu; Healy, Robert M; Flaud, Pierre-Marie; Perraudin, Emilie; Wenger, John C; Villenave, Eric

    2015-11-12

    The chlorine atom (Cl)-initiated oxidation of three polycyclic aromatic hydrocarbons (PAHs; namely, naphthalene, acenaphthylene, and acenaphthene) was investigated. Experiments were performed in an atmospheric simulation chamber using a proton transfer reaction time-of-flight mass spectrometer (TOF-MS) and an aerosol TOF-MS to characterize the oxidation products in the gas and particle phases, respectively. The major products identified from the reaction of Cl atoms with naphthalene were phthalic anhydride and chloronaphthalene, indicating that H atom abstraction and Cl addition reaction pathways are both important. Acenaphthenone was the principal product arising from reaction of Cl with acenaphthene, while 1,8-naphthalic anhydride, acenaphthenone, acenaphthenequinone, and chloroacenaphthenone were all identified as products of acenaphthylene oxidation, confirming that the cylcopenta-fused ring controls the reactivity of these PAHs toward Cl atoms. Possible reaction mechanisms are proposed for the formation of these products, and favored pathways have been suggested. Large yields of secondary organic aerosol (SOA) were also observed in all experiments, and the major products were found to undergo significant partitioning to the particle-phase. This work suggests that Cl-initiated oxidation could play an important role in SOA formation from PAHs under specific atmospheric conditions where the Cl atom concentration is high, such as the marine boundary layer. PMID:26472257

  15. Structural and dynamical properties of chlorinated hydrocarbons studied with resonant inelastic x-ray scattering.

    PubMed

    Bohinc, R; Žitnik, M; Bučar, K; Kavčič, M; Carniato, S; Journel, L; Guillemin, R; Marchenko, T; Kawerk, E; Simon, M; Cao, W

    2016-04-01

    We present a theoretical and experimental study of resonant inelastic x-ray scattering on a large group of chlorinated hydrocarbons: CH3Cl, CH2Cl2, CHCl3, CCl4, CH3CH2Cl, ClCH2CH2Cl, CH3CHCl2, CH3CCl3, C2H2Cl2-iso, C2H2Cl2-cis, C2H2Cl2-trans, and C6H5Cl. Differences in structural and dynamical properties of the molecules generated by diverse chemical environments are observed in the measured Cl(Kα) spectral maps as well as in the Cl(K) total fluorescence yield spectra. The energy position, relative intensity, and the width of the Franck-Condon distribution of low-lying σ(∗) and π(∗) resonances are extracted by a fitting procedure taking into account the experimental broadening. The theoretical values obtained with the transition potential and Δ Kohn-Sham methods are in good agreement with the experimental parameters indicating subtle differences due to variations in the molecular structure. PMID:27059572

  16. Structural and dynamical properties of chlorinated hydrocarbons studied with resonant inelastic x-ray scattering

    NASA Astrophysics Data System (ADS)

    Bohinc, R.; Žitnik, M.; Bučar, K.; Kavčič, M.; Carniato, S.; Journel, L.; Guillemin, R.; Marchenko, T.; Kawerk, E.; Simon, M.; Cao, W.

    2016-04-01

    We present a theoretical and experimental study of resonant inelastic x-ray scattering on a large group of chlorinated hydrocarbons: CH3Cl, CH2Cl2, CHCl3, CCl4, CH3CH2Cl, ClCH2CH2Cl, CH3CHCl2, CH3CCl3, C2H2Cl2-iso, C2H2Cl2-cis, C2H2Cl2-trans, and C6H5Cl. Differences in structural and dynamical properties of the molecules generated by diverse chemical environments are observed in the measured Cl(Kα) spectral maps as well as in the Cl(K) total fluorescence yield spectra. The energy position, relative intensity, and the width of the Franck-Condon distribution of low-lying σ∗ and π∗ resonances are extracted by a fitting procedure taking into account the experimental broadening. The theoretical values obtained with the transition potential and Δ Kohn-Sham methods are in good agreement with the experimental parameters indicating subtle differences due to variations in the molecular structure.

  17. Contamination of stream fishes with chlorinated hydrocarbons from eggs of Great Lakes salmon

    SciTech Connect

    Merna, J.W.

    1986-01-01

    Pacific salmon Oncorhynchus spp. have been stocked in the Great Lakes where they accumulate body burdens of chlorinated hydrocarbons. The transport of these contaminants to resident communities in spawning streams was studied in two tributaries of Lake Michigan accessible to anadromous spawners and one control tributary blocked to them. No polychlorinated biphenyls (PCBs), DDT, or dieldrin were detected in the sediments or biota of the control stream, or in sediments of the test streams. However, trout Salmo spp. and, to a lesser extent, sculpins Cottus spp. accumulated PCBs and DDT as a result of eating contaminated salmon eggs. Eggs constituted as much as 87% (by weight) of the total stomach contents of trout collected during the salmon spawning season early October to early January. Salmon eggs contained 0.46-9.50 mg PCBs/kg,. and 0.14-1.80 mg DDT/kg. Consumption of eggs varied greatly among individual trout, and there was a strong correlation between numbers of eggs in the stomachs and PCB and DDT concentrations in the fillets.

  18. Variations of volatile chlorinated hydrocarbons in ambient air at industrial areas in Niigata

    SciTech Connect

    Kawata, K.; Mukai, H.; Tanabe, H.; Yasuhara, A.

    1996-07-01

    Typical volatile chlorinated hydrocarbons (VCHs), 1,1,1-trichloroethane (methyl chloroform, MCF), and trichloroethane (trichloroethylene, TCE) are used as degreasers or cleaners at electrical plants and metalworks; tetrachloroethane (perchloroethylene, PCE) as well as MCF is representative solve-its for dry cleaning. Tetrachloromethane (perchloromethane, PCM) utilized as material for chemicals. Some amounts of VCHs are lost in the process and are introduced to the environment by some routes. In particular, direct exhaust of VCHs into air is one of the most serious routes; 60 to 90 percents of the VCHs used at some metalworks and relative factories were estimated to be emitted into air. Previously reported were the concentration levels of the VCHs in ambient air at some areas the atmospheric VCH concentrations at industrial areas were affected with some factories which used the VCHs, whereas those at a suburban area were lower than those at industrial regions. Furthermore, they were higher in winter season than in summer season, which might be caused by -meteorological factors. In this paper, aerial variations of VCH concentrations during two to five years at three individual industrial areas (i.e., a metalware and houseware manufacturing area, a textile and dyeing industrial area and a chemical engineering area) are presented. 14 refs., 2 figs., 2 tabs.

  19. Microbiota associated with the migration and transformation of chlorinated aliphatic hydrocarbons in groundwater.

    PubMed

    Guan, Xiangyu; Liu, Fei; Xie, Yuxuan; Zhu, Lingling; Han, Bin

    2013-08-01

    Pollution of groundwater with chlorinated aliphatic hydrocarbons (CAHs) is a serious environmental problem which is threatening human health. Microorganisms are the major participants in degrading these contaminants. Here, groundwater contaminated for a decade with CAHs was investigated. Numerical simulation and field measurements were used to track and forecast the migration and transformation of the pollutants. The diversity, abundance, and possible activity of groundwater microbial communities at CAH-polluted sites were characterized by molecular approaches. The number of microorganisms was between 5.65E+05 and 1.49E+08 16S rRNA gene clone numbers per liter according to quantitative real-time PCR analysis. In 16S rRNA gene clone libraries constructed from samples along the groundwater flow, eight phyla were detected, and Proteobacteria were dominant (72.8 %). The microbial communities varied with the composition and concentration of pollutants. Meanwhile, toluene monooxygenases and methane monooxygenases capable of degradation of PCE and TCE were detected, demonstrating the major mechanism for PCE and TCE degradation and possibility for in situ remediation by addition of oxygen in this study. PMID:23420483

  20. Direct immunofluorescence and enzyme-linked immunosorbent assays for evaluating chlorinated hydrocarbon degrading bacteria

    SciTech Connect

    Brigmon, R.L.; Franck, M.M.; Brey, J.; Fliermans, C.B.; Scott, D.; Lanclos, K.

    1997-06-01

    Immunological procedures were developed to enumerate chlorinated hydrocarbon degrading bacteria. Polyclonal antibodies (Pabs) were produced by immunizing New Zealand white rabbits against 18 contaminant-degrading bacteria. These included methanotrophic and chlorobenzene (CB) degrading species. An enzyme-linked immunosorbent assay (ELISA) was used to test for specificity and sensitivity of the Pabs. Direct fluorescent antibodies (DFAs) were developed with these Pabs against select methanotrophic bacteria isolated from a trichloroethylene (TCE) contaminated landfill at the Savannah River Site (SRS) and cultures from the American Type Culture Collection (ATCC). Analysis of cross reactivity testing data showed some of the Pabs to be group specific while others were species specific. The threshold of sensitivity for the ELISA is 105 bacteria cells/ml. The DFA can detect as few as one bacterium per ml after concentration. Results from the DFA and ELISA techniques for enumeration of methanotrophic bacteria in groundwater were higher but not significantly different (P < 0.05) compared to indirect microbiological techniques such as MPN. These methods provide useful information on in situ community structure and function for bioremediation applications within 1--4 hours of sampling.

  1. Investigations of the interaction of Spartina alterniflora loisel. and the chlorinated hydrocarbons, the polychlorinated biphenyls

    SciTech Connect

    Mrozek, E. Jr.

    1981-01-01

    Polychlorinated biphenyls (PCB's) are a class of industrial chlorinated hydrocarbons which are toxic to a broad range of organisms, persistent in the environment, and tend to accumulate in estuaries, where they are available to organisms at all trophic levels. Greenhouse and laboratory studies were initiated to characterize the interaction of Spartina alterniflora Loisel, and the PCB's. Particular areas addressed were: (1) uptake, translocation, and accumulation, (2) selectivity of uptake, (3) effects of uptake and/or exposure of PCB's on S. alterniflora growth, and (4) potential for transfer of PCB's from S. alterniflora and marsh substrate to Uca pugnax (fiddler crab). In a greenhouse study it was concluded that S. alterniflora has the capacity to take up, translocate and accumulate /sup 14/C-radioactivity from sand and marsh mud originally treated with /sup 14/C-PCB's. Fiddler crabs (U. pugnax) were exposed to /sup 14/C-PCB's applied to marsh substrate or S. alterniflora plant material which had been grown in the presence of /sup 14/C-PCB's to determine if marsh substrate-to-organism and plant-to-organism PCB transfer was possible. Results indicate that transfer from both sources occurred but that accumulation of /sup 14/C-radioactivity was only observed with crabs exposed to /sup 14/C-PCB treated substrate.

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

    PubMed Central

    Oldenhuis, R; Oedzes, J Y; van der Waarde, J J; Janssen, D 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 Vmax values of 550, 330, and 290 nmol min-1 mg of cells-1, respectively. 1,1-Dichloroethylene was a very poor substrate. TCE was found to be toxic for the cells, and this phenomenon was studied in detail. Addition of activated carbon decreased the acute toxicity of high levels of TCE by adsorption, and slow desorption enabled the cells to partially degrade TCE. TCE was also toxic by inactivating the cells during its conversion. The degree of inactivation was proportional to the amount of TCE degraded; maximum degradation occurred at a concentration of 2 mumol of TCE mg of cells-1. During conversion of [14C]TCE, various proteins became radiolabeled, including the alpha-subunit of the hydroxylase component of soluble methane monooxygenase. This indicated that TCE-mediated inactivation of cells was caused by nonspecific covalent binding of degradation products to cellular proteins. Images PMID:2036023

  3. CHLORINE 'DISINFECTION' CHEMISTRY OF AROMATIC COMPOUNDS. POLYNUCLEAR AROMATIC HYDROCARBONS: RATES, PRODUCTS, AND MECHANISMS

    EPA Science Inventory

    The use of chlorine for water renovation and disinfection has been questioned because of the reaction of active chlorine species with organic compounds present in water to form products that may be biologically harmful. Among the organic species known to be present during chlorin...

  4. In situ sensing of subsurface contamination--part I: near-infrared spectral characterization of alkanes, aromatics, and chlorinated hydrocarbons.

    PubMed

    Klavarioti, Maria; Kostarelos, Konstantinos; Pourjabbar, Anahita; Ghandehari, Masoud

    2014-05-01

    There is an imperative need for a chemical sensor capable of remote, in situ, long-term monitoring of chemical species at sites containing toxic chemical spills, specifically at chemical waste dumps, landfills, and locations with underground storage tanks. In the current research, a series of experiments were conducted measuring the near-infrared optical absorption of alkanes, aromatics, and chlorinated hydrocarbons. A spectral library was then developed to characterize the optical spectra of liquid hydrocarbons. Near-infrared analysis was chosen due to compatibility with optical fibers. The goal was to differentiate between classes of hydrocarbons and to also discriminate between compounds within a class of similar molecular structures. It was observed that unique absorption spectra can be obtained for each hydrocarbon, and this uniqueness can be used to discriminate between hydrocarbons from different families. Statistical analyses, namely, principal component analysis (PCA) and correlation coefficient (Spearman and Pearson methods), were attempted to match absorption spectra from an unknown hydrocarbon with the database with limited success. An algorithm was subsequently written to identify the characteristic peaks of each hydrocarbon that could be used to match data from an unknown chemical species with the database. PMID:24445930

  5. The Efficacy of Residual Chlorine Content on the Control of Legionella Spp. In Hospital Water Systems

    PubMed Central

    RAFIEE, Mohammad; MESDAGHINIA, Alireza; HAJJARAN, Homa; HAJAGHAZADEH, Mohammad; MIAHIPOUR, Abolfazl; JAHANGIRI-RAD, Mahsa

    2014-01-01

    Abstract Background Outbreaks of legionellosis may be a side effect of institution-water treatment. However, the long-term outcomes and the predictive factors of Legionella prevalence in such systems have still not been fully studied. This study was therefore conducted to investigate the prevalence of Legionella spp. and to evaluate the role of bacteriological water quality parameters on its prevalence and removal in hospital water systems. Methods A total of 45 samples were collected from distinct sites at seven hospitals in Tehran, Iran. The prevalence of this bacterium was assayed through a sensitive and specific technique for DNA detection using PCR. Multivariable stepwise regression analysis was used to explore the independent effects of the baseline factors on the incidence of Legionella. Two positive samples were also identified for species by DNA sequencing. Results Legionella were detected in 31.1% of samples. Showerheads and cold-water taps were the most and the least contaminated sources with 55.3 and 9 percent positive samples, respectively. Total mean of residual chlorine was 0.38 mg/L, with the peak value of 1.7 mg/L. Legionella detection was proportional to the residual chlorine content of water and the results indicated that residual chlorine content is a critical factor in the incidence and proliferation of Legionella (r=-0.33). The prevalence of Legionella also coincided with the prevalence of HPC and amoeba cysts. Conclusion The high positive rate of Legionella colonization shows that hospital-acquired legionellosis might be under diagnosed in studied hospitals. Further, Legionella colonization is independent of the type of water, system characteristics and of preventive maintenance measures. PMID:26060765

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

    PubMed

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

    1999-02-01

    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 gland and baculum masses, baculum length, and stomach contents. Livers were analyzed, individually or in pools, for residues of organochlorine (OC) pesticides, polychlorinated biphenyls (PCBs), dibenzo-p-dioxins, and dibenzofurans. Contaminant levels were relatively low compared to those documented in other North American populations, although they ranged higher than those detected during an earlier survey (1990-1992) of these regional populations. Body condition varied slightly among collection regions, but showed no relationship with contaminant burden. Mink from the upper Fraser River had less fat stores and also had some of the lowest OC contamination levels observed. Similarly, a few individuals with enlarged livers and kidneys had low contaminant levels. Although a few individual animals with gross abnormalities of reproductive systems did not show high levels of contamination, there was a significant negative correlation between total PCB concentrations (as Aroclor 1260) and baculum length in juvenile mink (r = 0.707; p = 0.033; n = 8). The association of juvenile baculum length with eventual reproductive success is unknown, but further characterization of reproductive organ morphology and relationship to contaminants should be undertaken in a larger subset of these populations. PMID:9924010

  7. Occurrence and profiles of chlorinated and brominated polycyclic aromatic hydrocarbons in waste incinerators.

    PubMed

    Horii, Yuichi; Ok, Gon; Ohura, Takeshi; Kannanct, Kurunthachalam

    2008-03-15

    Chlorinated polycyclic aromatic hydrocarbons (CIPAHs) have been reported to occur in urban air. Nevertheless, sources of CIPAHs in urban air have not been studied, due to the lack of appropriate analytical methods and standards. In this study, we measured concentrations of 20 CIPAHs and 11 brominated PAHs (BrPAHs) in fly ash and bottom ash from 11 municipal/hazardous/industrial waste incinerators, using analytical standards synthesized in our laboratory. Concentrations of total CIPAHs and BrPAHs in ash samples ranged from <0.06 to 6990 ng/g and from <0.14 to 1235 ng/g, respectively. The concentrations of CIPAHs were approximately 100-fold higher than the concentrations of BrPAHs. 6-CIBaP and 1-CIPyr were the dominant compounds in fly ash samples. The profiles of halogenated PAHs were similar to the profiles reported previously for urban air. 1-BrPyr was the predominant BrPAH in fly ash. Concentrations of 6-CIBaP, 9,10-Cl2Phe, 9-CIAnt, and 6-BrBaP in fly ash were significantly correlated with the corresponding parent PAH concentrations. Significant correlation between sigmaCIPAH and sigmaPAH concentrations suggests that direct chlorination of parent PAHs is the mechanism of formation of CIPAHs during incineration of wastes; nevertheless, a comparable correlation was not found for BrPAHs. There was no significant correlation between the capacity and temperature of an incinerator and the concentrations of sigmaCl-/BrPAHs in ash samples, although lower concentrations of all halogenated PAHs were found in stoker-type incinerators than in fixed grate-type incinerators. Toxicity equivalency quotients (TEQs) for CIPAHs in ash samples were calculated with CIPAH potencies. Average TEQ concentrations of CIPAHs in fly ash and bottom ash were15800 pg-TEQ/g and 67 pg-TEQ/g, respectively. Our results suggest that the extent of dioxin-like toxicity contributed by CIPAHs in ash generated during waste incineration is similar to that reported previously for dioxins. Waste

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

    PubMed

    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

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

    USGS Publications Warehouse

    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 (< 1-34 ng/g). PCBs are first detected in sediment deposited during the 1930's in Richardson Bay, about a decade earlier than the onset of detectable levels of DDTs. PCB 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.

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

    NASA Astrophysics Data System (ADS)

    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] ~ 1.9 mg L- 1, and initial aqueous [CAH] ~ 150 μg L- 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 ± 0.07 d- 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.

  11. Effects of Occupational Exposure to Mercury or Chlorinated Hydrocarbons on the Auditory Pathway.

    PubMed

    Moshe, Shlomo; Frenkel, Avraham; Hager, Moshe; Skulsky, Mario; Sulkis, Jacklin; Himelfarbe, Mordechai

    2002-01-01

    The purpose of this study was to examine the effects of industrial exposure to mercury and chlorinated hydrocarbons (CH) on the auditory pathway. To this effect, auditory brainstem responses (ABR) were recorded from 40 workers exposed to mercury, 37 workers exposed to CH and from a control group of 36 subjects that were never exposed to neurotoxic substances. The interpeak latency (IPL) of waves I-III, III-V and I-V were measured. The mean duration of exposure to mercury and CH was 15.5 (+6.4) and 15.8 (+7.2) years respectively. The air sample monitoring of mercury was 0.008 mg/m(3) (0.32 of the Threshold Limit Value - TLV(R) as published by ACGIH 2000). The mean average air sample monitoring was found to be 98 ppm for TCE, 12.7 ppm for PCE and 14.4 ppm for TCA which is respectively between 0.28 - 0.51 of the TLV(R) of CH. The mean blood mercury (B-Hg) levels were found to be 0.5mgr% (+0.3mgr%), which is 0.13 of the upper range of the permitted biologic exposure index (BEI) published by the ACGIH 2000. The mean urine samples levels of trichloroacetic acid were between 0.11-0.2 of the permitted BEI for the CH workers. The percent of workers exposed to mercury and CH workers with abnormal prolongation of IPL I-III was higher than the control group (42.5% and 33.8% vs. 18.0% respectively p<0.02). These results are consistent with other studies and show that ABR may provide a sensitive tool for detecting subclinical central neurotoxicity caused by CH and mercury PMID:12537844

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

    PubMed

    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. PMID:25433980

  13. Determination of volatile chlorinated hydrocarbons in water samples by static headspace gas chromatography with electron capture detection.

    PubMed

    Li, Tiejun; Guo, Yuanming; Hu, Hongmei; Zhang, Xiaoning; Jin, Yanjian; Zhang, Xiaojun; Zhang, Yurong

    2016-01-01

    A simple, efficient, solvent-free, and commercial readily available approach for determination of five volatile chlorinated hydrocarbons in water samples using the static headspace sampling and gas chromatography with electron capture detection has been described. The proposed static headspace sampling method was initially optimized and the optimum experimental conditions found were 10 mL water sample containing 20% w/v sodium chloride placed in a 20 mL vial and stirred at 50ºC for 20 min. The linearity of the method was in the range of 1.2-240 μg/L for dichloromethane, 0.2-40 μg/L for trichloromethane, 0.005-1 μg/L for perchloromethane, 0.025-5 μg/L for trichloroethylene, and 0.01-2 μg/L for perchloroethylene, with coefficients of determination ranging between 0.9979 and 0.9990. The limits of detection were in the low μg/L level, ranging between 0.001 and 0.3 μg/L. The relative recoveries of spiked five volatile chlorinated hydrocarbons with external calibration method at different concentration levels in pure, tap, sea water of Jiaojiang Estuary, and sea water of waters of Xiaomendao were in the range of 91-116, 96-105, 86-112, and 80-111%, respectively, and with relative standard deviations of 1.9-3.6, 2.3-3.5, 1.5-2.7, and 2.3-3.7% (n = 5), respectively. The performance of the proposed method was compared with traditional liquid-liquid extraction on the real water samples (i.e., pure, tap, and sea water, etc.) and comparable efficiencies were obtained. It is concluded that this method can be successfully applied for the determination of volatile chlorinated hydrocarbons in different water samples. PMID:26805957

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

    NASA Astrophysics Data System (ADS)

    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

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

    PubMed

    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. PMID:25444117

  16. Patterns and trends of chlorinated hydrocarbons in nestling bald eagle (Haliaeetus leucocephalus) plasma in British Columbia and Southern California.

    PubMed

    Cesh, Lillian S; Williams, Tony D; Garcelon, David K; Elliott, John E

    2008-10-01

    Patterns and trends of chlorinated hydrocarbons were assessed in bald eagle nestling plasma from sites along the west coast of North America. Eagle plasma was sampled from four areas in southwestern British Columbia (BC), a reference site in northern BC, and from Santa Catalina Island, off the coast of California. Sites were chosen to reflect variation in contaminant exposure due to differing recent and/or historic anthropogenic activities. Santa Catalina Island had significantly greater mean concentrations of p,p'-DDE, 41.3 microg/kg wet weight (ww), than other sites, and Nanaimo/Crofton, BC had the greatest mean concentration of total PCBs, 28.9 microg/kg ww. Contaminant levels measured in 2003 in BC were compared to levels measured in 1993; over that ten year span, concentrations and patterns of chlorinated hydrocarbons have not significantly changed. There were no significant differences in levels of p,p'-DDE or hexachlorobenzene between 1993 and 2003, but significant decreases were found for trans-nonachlor and PCBs at BC sites. Levels of total PCBs and trans-nonachlor in the central Fraser Valley and Nanaimo/Crofton area have significantly decreased. Mean concentrations of p,p'-DDE measured in bald eagle nestling plasma samples in 2003 exceeded published criteria for effects on bald eagle reproduction at Santa Catalina Island and Barkley Sound, more than 30 years since heavy usage restrictions were imposed. PMID:18253687

  17. Evidence for Perchlorates and the Origin of Chlorinated Hydrocarbons Detected by SAM at the Rocknest Aeolian Deposit in Gale Crater

    NASA Technical Reports Server (NTRS)

    Glavin, Daniel P.; Freissinet, Caroline; Miller, Kristen E.; Eigenbrode, Jennifer L.; Brunner, Anna E.; Buch, Arnaud; Sutter, Brad; Archer, P. Douglas, Jr.; Atreya, Sushil K.; Brinckerhoff, William B.; Cabane, Michael; Coll, Patrice; Conrad, Pamela G.; Coscia, David; Dworkin, Jason P.; Franz, Heather B.; Grotzinger, John P.; Leshin, Laurie A.; Martin, Mildred G.; McKay, Christopher; Ming, Douglas W.; Navarro-Gonzalez, Rafael; Pavlov, Alexander; Steele, Andrew; Summons, Roger E.; Szopa, Cyril; Teinturier, Samuel; Mahaffy, Paul R.

    2013-01-01

    Four individual sample portions from a single scoop of the Rocknest aeolian deposit were sieved ( 150 m) and delivered to the Sample Analysis at Mars (SAM) instrument by the Mars Science Laboratory rover's sample acquisition system. The samples were analyzed separately by the SAM pyrolysis evolved gas and gas chromatography mass spectrometry analysis modes. Several chlorinated hydrocarbons including chloromethane, dichloromethane, trichloromethane, a chloromethylpropene, and chlorobenzene were identified by SAM above background levels with abundances of 0.01 to 2.3 nanomole.The evolution of the chloromethanes observed during pyrolysis is coincident with the increase in O2 released from the Rocknest sample and the decomposition of a product of N-methyl-N- (tert-butyldimethylsilyl)trifluoroacetamide (MTBSTFA), a chemical that leaked from a derivatization cup inside SAM.The best candidate for the oxychloride phase in Rocknest is a hydrated calcium perchlorate (Ca(ClO4)2nH2O), based on the temperature release of O2 that correlates with the release of the chlorinated species measured by SAM, although other chlorine bearing phases are being considered. Laboratory pyrolysis experiments suggest that reaction of martian chlorine with organic carbon from MTBSTFA can explain the presence of the chloromethanes and a chloromethylpropene also detected by SAM.However, we cannot exclude the possibility that traces of organic carbon of either martian or exogenous origin contributed to some of the chloromethanes measured by SAM. Although the alteration history and exposure age of the Rocknest deposit is unknown, it is possible that oxidative degradation of complex organic matter by ionizing radiation or other chemical processes in Rocknest has occurred.

  18. Interpreting residues of petroleum hydrocarbons in wildlife tissues

    USGS Publications Warehouse

    Hall, R.J.; Coon, N.C.

    1988-01-01

    A brief guidance publication that explains how to evaluate reports of petroleum concentrations in animal tissue. Sections on background, sampling and handling of samples, reports and interpretation, when to analyze for hydrocarbons, and how to interpret the magnitude of the concentrations.

  19. [Distribution of hydrocarbon residues in the sediment from Bizerte lagoon (Northern Tunisia)].

    PubMed

    Soussi, N

    1983-01-01

    The study of hydrocarbon residue by infrared spectrophotometry in the deposits of the Bizerta Lagoon allows us to recognize a polluted zone sector of the Menzel Bourguiba Arsenal. The Eastern part of the lagoon, a zone of "oyster parks" is not affected by pollution. Its average contents of hydrocarbon residues are clearly below the maximum content determined by international regulations. The distribution of hydrocarbon residues in the superficial sediments following three well differentiated zones, reflects the weak hydrodynamism in the lagoon. The vertical variations of this pollution agent contents show the preferential accumulation of the terrigenous material, from lake Ichkeul , in the western part and the weak rate of sedimentation in the eastern zone. PMID:6677195

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

    EPA Science Inventory

    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...

  1. The indirect determination of chlorine atom concentration in the troposphere from changes in the patterns of non-methane hydrocarbons

    NASA Astrophysics Data System (ADS)

    Rudolph, J.; Ramacher, B.; Plass-Dülmer, C.; Müller, K.-P.; Koppmann, R.

    1997-11-01

    About 200 measurements of C2 C9 hydrocarbons were made during a ship cruise (NATAC 91) in the western Mediterranean Sea, the eastern Mid- and North Atlantic and the North Sea in April and May 1991. The changes in the ratios of several pairs of hydrocarbons are used to investigate the possible impact of Cl-atom reactions on the atmospheric removal processes of hydrocarbons. In order to minimize the potential bias from atmospheric mixing processes, a careful selection of suitable hydrocarbon sets is essential. The NMHC mixing ratios observed during NATAC 91 are generally well above those typical for air in the remote marine background and the observed changes in the hydrocarbon patterns agree very well with those predicted from OH-radical chemistry. No significant evidence for an impact of chlorine atoms could be found in this data set. The best estimate for the average [Cl]/[OH] ratio is in the range of 10-3. However, within the various uncertainties associated with such estimates, this value is not significantly different from zero. The upper limit is in the range of 2 7·10-3. Based on an average OH-radical concentration of 106 cm-3, this corresponds to some 103 Cl-atoms cm-3. This is far below the Cl-atom concentrations found during the tropospheric ozone depletion events in arctic spring. Our values are also far below those derived in some other studies for the marine boundary layer but are still compatible with recent model calculations. Our findings support the conclusion of Rudolph and coworkers that on average, Cl-atoms are of limited importance for the chemistry of the troposphere. It is important that

  2. Bidet toilet seats with warm-water tanks: residual chlorine, microbial community, and structural analyses.

    PubMed

    Iyo, Toru; Asakura, Keiko; Nakano, Makiko; Yamada, Mutsuko; Omae, Kazuyuki

    2016-02-01

    Despite the reported health-related advantages of the use of warm water in bidets, there are health-related disadvantages associated with the use of these toilet seats, and the bacterial research is sparse. We conducted a survey on the hygienic conditions of 127 warm-water bidet toilet seats in restrooms on a university campus. The spray water from the toilet seats had less residual chlorine than their tap water sources. However, the total viable microbial count was below the water-quality standard for tap water. In addition, the heat of the toilet seats' warm-water tanks caused heterotrophic bacteria in the source tap water to proliferate inside the nozzle pipes and the warm-water tanks. Escherichia coli was detected on the spray nozzles of about 5% of the toilet seats, indicating that the self-cleaning mechanism of the spray nozzles was largely functioning properly. However, Pseudomonas aeruginosa was detected on about 2% of the toilet seats. P. aeruginosa was found to remain for long durations in biofilms that formed inside warm-water tanks. Infection-prevention measures aimed at P. aeruginosa should receive full consideration when managing warm-water bidet toilet seats in hospitals in order to prevent opportunistic infections in intensive care units, hematology wards, and other hospital locations. PMID:26837831

  3. PLANAR CHLORINATED HYDROCARBONS (PCHS) IN COLONIAL FISH-EATING WATERBIRD EGGS FROM THE GREAT LAKES

    EPA Science Inventory

    Reproductive impairment of double-crested cormorants (Phalacrocorax auritis) and Caspian terns Hydroprogne caspia) has recently been observed in the Great Lakes of North America. lanarchlorinated hydrocarbons (PCHs), which include polychlorinated biphenyls (PCBs), polychlorinated...

  4. Use of tree rings to investigate the onset of contamination of a shallow aquifer by chlorinated hydrocarbons

    USGS Publications Warehouse

    Yanosky, T.M.; Hansen, B.P.; Schening, M.R.

    2001-01-01

    Oaks (Quercus velutina Lam.) growing over a shallow aquifer contaminated by chlorinated hydrocarbons were studied to determine if it was possible to estimate the approximate year that contamination began. The annual rings of some trees downgradient from the contaminant release site contained elevated concentrations of chloride possibly derived from dechlorination of contaminants. Additionally, a radial-growth decline began in these trees at approximately the same time that chloride became elevated. Growth did not decline in trees that contained smaller concentrations of chloride. The source of elevated chloride and the corresponding reductions in tree growth could not be explained by factors other than contamination. On the basis of tree-ring evidence alone, the release occurred in the late 1960s or early 1970s. Contaminant release at a second location apparently occurred in the mid- to late 1970s, suggesting that the area was used for disposal for at least 5 years and possibly longer. Copyright ?? 2001 Elsevier Science B.V.

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

    PubMed

    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

  6. Polycyclic aromatic hydrocarbons residues in sandstorm depositions in Beijing, China.

    PubMed

    Fu, S; Li, K; Xia, X J; Xu, X B

    2009-02-01

    This study was conducted to determine the concentration of 16 polycyclic aromatic hydrocarbons (PAHs) in sandstorm depositions in Beijing, China. The PAH concentrations in 13 samples collected in Beijing ranged from 0.18 to 3.52 microg g(-1). Analysis of the sources of contamination revealed that the PAHs were derived from a coal combustion source, although various effects of traffic emissions were also observed. Furthermore, the PAH levels in Beijing tended to be higher in the southeast. Finally, the nemerow composite index revealed that the degree of pollution in the sandstorm depositions varied widely among sampling sites. PMID:18773130

  7. Occurrence and source of chlorinated polycyclic aromatic hydrocarbons (Cl-PAHs) in tidal flats of the Ariake Bay, Japan.

    PubMed

    Sankoda, Kenshi; Kuribayashi, Tomonori; Nomiyama, Kei; Shinohara, Ryota

    2013-07-01

    In this study, we hypothesize that natural photochemical reactions of polycyclic aromatic hydrocarbons (PAHs) in tidal flats are responsible for the occurrence of chlorinated polycyclic aromatic hydrocarbons (Cl-PAHs). This study aims to survey the impact of photochemical reactions using a combination of field surveys and lab-scale experiments. Concentrations and profiles of PAHs and Cl-PAHs in road dust and sediments collected from seven tunnels and two watersheds, respectively, were determined. In the lab-scale experiments, anthracene was irradiated with ultraviolet (UV) light under various salinity conditions. No detectable Cl-PAHs were found in the road dust. However, Cl-PAHs were detected in the sediments from 700 to 6.1 × 10(3) pg g(-1) and specifically from downstream sites. 2-Monochloroanthracene (2-Cl-ANT) and 9,10-dichloroanthracene (9,10-di-Cl-ANT) were dominant in the sediments. In the Domen River watershed, the ∑Cl-PAHs and the salinity showed a significant positive correlation (p < 0.01) in the sediments, while such a correlation was not found for PAHs. 2-Cl-ANT, 9-monochloroanthracene, and 9,10-di-Cl-ANT were identified as transformation products in the UV irradiation experiments. Production of these Cl-PAHs was dependent on the solution salinity. These results support our hypothesis, and we conclude that photochemical reactions significantly contribute to the occurrence of Cl-PAHs in the studied tidal flats. PMID:23452146

  8. BIOTRANSFORMATION OF MONOAROMATIC AND CHLORINATED HYDROCARBONS AT AN AVIATION GASOLINE SPILL SITE

    EPA Science Inventory

    A shallow water table aquifer under the U.S. Coast Guard Air Station at Traverse City, MI, has acclimated to the aerobic and anaerobic transformation of monoaromatic hydrocarbons (BTX) released from an aviation gasoline spill. The aquifer also exhibits reductive dechlorination of...

  9. BIOTRANSFORMATION OF MONOAROMATIC AND CHLORINATED HYDROCARBONS AT AN AVIATION GASOLINE SPILL SITE

    EPA Science Inventory

    A shallow water table aquifer under the U.S Coast Guard Air Station at Traverse City, MI, has acclimated to the aerobic and anaerobic transformation of monoaromatic hydrocarbons (BTX) released from an aviation gasoline spill. he aquifer also exhibits reductive dechlorination of a...

  10. TAILORING CATALYSTS FOR HYDRODECHLORINATING CHLORINATED HYDROCARBON CONTAMINANTS IN GROUNDWATER. (R825689C078)

    EPA Science Inventory

    Abstract

    A palladium-on-zeolite catalyst has been optimized for treating groundwater contaminated with halogenated hydrocarbon compounds (HHCs) by hydrodechlorination with dissolved hydrogen. Aqueous sulfite was used as the model poison and the dechlorination of 1,2-di...

  11. TAILORING CATALYSTS FOR HYDRODECHLORINATING CHLORINATED HYDROCARBON CONTAMINANTS IN GROUNDWATER. (R825689C093)

    EPA Science Inventory

    Abstract

    A palladium-on-zeolite catalyst has been optimized for treating groundwater contaminated with halogenated hydrocarbon compounds (HHCs) by hydrodechlorination with dissolved hydrogen. Aqueous sulfite was used as the model poison and the dechlorination of 1,2-di...

  12. Immunoquantitation and microsomal monooxygenase activities of hepatic cytochromes P4501A and P4502B and chlorinated hydrocarbon contaminant levels in polar bear (Ursus maritimus).

    PubMed

    Letcher, R J; Norstrom, R J; Lin, S; Ramsay, M A; Bandiera, S M

    1996-04-01

    Contamination of the Arctic ecosystem by anthropogenic compounds has resulted in exposure of polar bear (Ursus maritimus) to lipophilic chlorinated hydrocarbon contaminants (CHCs) accumulated through the marine food web. Liver samples were collected from 16 adult male polar bears in the Canadian arctic and subjected to chemical analysis for CHCs and metabolites, determination of alkoxyresorufin O-dealkylase activities, and immunoquantitation of cytochrome P450 (CYP) protein levels. We report on the relationships between the hepatic microsomal levels of immunoreactive CYP1A and CYP2B isozymes, catalytic activities, and hepatic CHC and metabolite concentrations in polar bear. We specifically explored the influence of several CHCs on the induction of hepatic CYP in polar bear and the potential use of immunoassay quantitation as a bioindicator of CHC exposure. Polychlorinated biphenyls (PCB) classed as CYP1A and mixed CYP1A/CYP2B inducers accounted for about 25% of the total PCB residues present (18,680 +/- 5053 ng/g lipid). CYP1A protein content correlated strongly with hepatic levels of PCBs, PCDDs (0.032 +/- 0.018 ng/g lipid, and PCDFs (0.011 +/- 0.007 ng/g lipid) and their corresponding toxic equivalents (TEQ, 0.377 +/- 0.182 ng/g lipid). Mono-ortho-CB-156, CB-157, and CB-105 were the predominant TEQ contributors. Correlations between CYP2B protein content and CHC residue levels in polar bear liver suggested that ortho-chlorine-substituted PCBs and chlordanes were the major contributors to CYP2B induction. CYP1A and CYP2B contents were therefore good indicators of CHC exposure in polar bear liver. Ethoxyresorufin, pentoxyresorufin, and benzyloxyresorufin O-dealkylase activities increased with increasing CYP1A protein content up to protein levels of approximately 5 pmol/mg, suggesting that all three activities were primarily CYP1A-mediated. These results were substantiated by antibody inhibition experiments. In summary, immunoquantitated CYP1A and CYP2B isozymes are

  13. Chlorinated hydrocarbons in the marine environment. A report prepared by the Panel on Monitoring Persistent Pesticides in the Marine Environment of the Committee on Oceanography

    USGS Publications Warehouse

    Panel on Monitoring Persistent Pesticides in the Marine Environment; Goldberg, E.D.; Butler, P.; Meier, P.; Menzel, D.; Paulik, G.; Risebrough, R.; Stickel, L.F.

    1971-01-01

    SUMMARY AND RECOMMENDATIONS : The oceans are an ultimate accumulation site for the persistent chlorinated hydrocarbons. As much as 25 percent of the DDT compounds produced to date may have been transferred to the sea. The amount of DDT compounds in the marine biota is estimated to be less than 0.1 percent of total production, yet this amount has produced a demonstrable impact upon the marine environment. Populations of fish-eating birds have experienced reproductive failure and decline. With continued accumulations of persistent chlorinated hydrocarbons in the marine ecosystem, additional species will be threatened. Continued release of these pollutants to the environment can only accelerate the accumulation of unacceptable levels of persistent chlorinated hydrocarbons in the tissues of marine food fish. Certain risks in the utilization of chlorinated hydrocarbons are especially hard to quantify, but they require serious consideration. The rate at which such substances degrade to harmless products in the marine system is unknown; the half-lives of some of the more persistent materials are certainly of the order of years, and perhaps even of decades or centuries. If most of the remaining 75 percent of the persistent chlorinated hydrocarbons is now in reservoirs that will in time transfer their contents to the sea, we may expect an increased level of these substances in marine organisms, despite future improvements of manufacturing practices. In fact, if these compounds degrade with half-lives of decades or longer, there will be no opportunity to redress the consequences. The more the problems are studied, the more unexpected effects are identified. In view of the findings of the past decade, our prediction of the potential hazards of chlorinated hydrocarbons in the marine environment may be vastly underestimated. The Panel makes the following recommendations, which will be developed and expanded in the remainder of the report: ? A massive national effort should be

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

    USGS Publications Warehouse

    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

  15. SYNOPTIC SURVEY OF CHLORINATED HYDROCARBON INPUTS TO THE SOUTHERN CALIFORNIA BIGHT. VOLUME I: SUMMARY REPORT

    EPA Science Inventory

    Of the seven input routes investigated (municipal wastewater, direct industrial discharge, vessel antifouling paints, harbor flushing, surface runoff, dry aerial fallout, and ocean current advection), during 1971-72 the largest quantities of DDTs and PCBs (the major residues obse...

  16. In situ recovery from residually heated sections in a hydrocarbon containing formation

    DOEpatents

    Vinegar, Harold J.; Karanikas, John Michael; Ryan, Robert Charles

    2010-12-14

    Methods of treating a tar sands formation is described herein. The methods may include providing heat to a first section of a hydrocarbon layer in the formation from a plurality of heaters located in the first section of the formation. Heat is transferred from the heaters so that at least a first section of the formation reaches a selected temperature. At least a portion of residual heat from the first section transfers from the first section to a second section of the formation. At least a portion of hydrocarbons in the second section are mobilized by providing a solvation fluid and/or a pressurizing fluid to the second section of the formation.

  17. Polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and chlorinated pesticides in background air in central Europe - investigating parameters affecting wet scavenging of polycyclic aromatic hydrocarbons

    NASA Astrophysics Data System (ADS)

    Shahpoury, P.; Lammel, G.; Holubová Šmejkalová, A.; Klánová, J.; Přibylová, P.; Váňa, M.

    2014-10-01

    Concentrations of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and chlorinated pesticides (CPs) were measured in air and precipitation at a background site in central Europe. Σ PAH concentrations in air and rainwater ranged from 0.7 to 327.9 ng m-3 and below analytical method detection limit (< MDL) to 2.1 × 103 ng L-1. The concentrations of PCBs and CPs in rainwater were < MDL. Σ PCB and Σ CP concentrations in air ranged from < MDL to 44.6 and < MDL to 351.7 pg m-3, respectively. The potential relationships between PAH wet scavenging and particulate matter and rainwater properties were investigated. The concentrations of ionic species in particulate matter and rainwater were significantly correlated, highlighting the importance of particle scavenging process. Overall, higher scavenging efficiencies were found for relatively less volatile PAHs, underlining the effect of analyte gas-particle partitioning on scavenging process. The PAH wet scavenging was more effective when the concentrations of ionic species were high. In addition, the elemental and organic carbon contents of the particulate matter were found to influence the PAH scavenging.

  18. Polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and chlorinated pesticides in background air in central Europe - investigating parameters affecting wet scavenging of polycyclic aromatic hydrocarbons

    NASA Astrophysics Data System (ADS)

    Shahpoury, P.; Lammel, G.; Holubová Šmejkalová, A.; Klánová, J.; Přibylová, P.; Váňa, M.

    2015-02-01

    Concentrations of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and chlorinated pesticides (CPs) were measured in air and precipitation at a background site in central Europe. ∑ PAH concentrations in air and rainwater ranged from 0.7 to 327.9 ng m-3 and below limit of quantification (< LOQ) to 2.1 × 103 ng L-1. The concentrations of PCBs and CPs in rainwater were < LOQ. ∑ PCB and ∑ CP concentrations in air ranged from < LOQ to 44.6 and < LOQ to 351.7 pg m-3, respectively. The potential relationships between PAH wet scavenging and particulate matter and rainwater properties were investigated. The concentrations of ionic species in particulate matter and rainwater were significantly correlated, highlighting the importance of particle scavenging process. Overall, higher scavenging efficiencies were found for relatively less volatile PAHs, underlining the effect of analyte gas-particle partitioning on scavenging process. The particulate matter removal by rain, and consequently PAH wet scavenging, was more effective when the concentrations of ionic species were high. In addition, the elemental and organic carbon contents of the particulate matter were found to influence the PAH scavenging.

  19. Chlorinated hydrocarbons in early life stages of the common snapping turtle (Chelydra serpentina serpentina) from a coastal wetland on Lake Ontario, Canada

    SciTech Connect

    Bishop, C.A.; Lean, D.R.S.; Carey, J.H.; Brooks, R.J.; Ng, P.

    1995-03-01

    To assess intra-clutch variation in contaminant concentrations in eggs, and to investigate the dynamics of chlorinated hydrocarbon accumulation in embryos of the common snapping turtle (Chelydra serpentina), concentrations of p,p{prime}-DDE, hexachlorobenzene, trans-nonachlor, cis-chlordane, and six PCB congeners were measured in eggs, embryos, and hatchlings. Samples were collected from Cootes Paradise, a wetland at the western end of Lake Ontario, Ontario, Canada. The intra-clutch variation in chlorinated hydrocarbon concentrations within four snapping turtle clutches was determined by analyzing the first, last, and middle five eggs oviposited in the nest. The first five eggs had the highest mean concentrations of all chlorinated hydrocarbons, wet weight, and egg diameter. On a lipid weight basis, the first five eggs contained the highest concentration of all compounds except total PCBs and cis-chlordane. The concentration of cis-chlordane was the only parameter measured that was significantly different among the three sets of eggs. At hatching, snapping turtles without yolk sacs contained from 55.2 to 90.5% of the absolute amount of organochlorine compounds measured in the egg at oviposition. Eighteen days after hatching, the body burden of PCBs and pesticides decreased to 45.3 to 62.2% of that in the fresh egg. The accumulation of organochlorine chemicals in embryonic turtles peaked at or just before hatching and then declined thereafter, which is consistent with trends reported in developing sea turtles, fish, and birds.

  20. Secondary aerosol formation from the oxidation of biogenic hydrocarbons by chlorine atoms

    NASA Astrophysics Data System (ADS)

    Cai, Xuyi; Griffin, Robert J.

    2006-07-01

    The chlorine atom (Cl) is a potential oxidant of volatile organic compounds (VOCs) in the atmosphere and is hypothesized to lead to secondary organic aerosol (SOA) formation in coastal and industrialized areas. The purpose of this paper is to test this hypothesis and to quantify the SOA formation potentials of the common monoterpenes α-pinene, β-pinene, and d-limonene when oxidized by Cl in laboratory chamber experiments. Results indicate that the oxidation of these monoterpenes generates significant amounts of aerosol. The SOA yields of α-pinene, β-pinene, and d-limonene in this study are comparable to those when they are oxidized by ozone, by nitrate radical, and in photooxidation scenarios. For aerosol mass up to 30.0 μg m-3, their yields reach approximately 0.20, 0.20, and 0.30, respectively. For d-limonene, data indicate two yield curves that depend on the initial concentration ratio of Cl precursor to d-limonene. It is argued theoretically that multiple SOA yield curves may be common for VOCs, depending on the initial concentration ratio of oxidant to VOC. SOA formation from the three typical monoterpenes when oxidized by Cl in the marine boundary layer, coastal areas, and inland industrialized areas could be a source of organic aerosol in the early morning.

  1. Thermal decomposition of selected chlorinated hydrocarbons during gas combustion in fluidized bed

    PubMed Central

    2013-01-01

    Background The process of thermal decomposition of dichloromethane (DCM) and chlorobenzene (MCB) during the combustion in an inert, bubbling fluidized bed, supported by LPG as auxiliary fuel, have been studied. The concentration profiles of C6H5CI, CH2Cl2, CO2, CO, NOx, COCl2, CHCl3, CH3Cl, C2H2, C6H6, CH4 in the flue gases were specified versus mean bed temperature. Results The role of preheating of gaseous mixture in fluidized bed prior to its ignition inside bubbles was identified as important factor for increase the degree of conversion of DCM and MCB in low bed temperature, in comparison to similar process in the tubular reactor. Conclusions Taking into account possible combustion mechanisms, it was identified that autoignition in bubbles rather than flame propagation between bubbles is needed to achieve complete destruction of DCM and MCB. These condition occurs above 900°C causing the degree of conversion of chlorine compounds of 92-100%. PMID:23289764

  2. Evaluation of Membrane Ultrafiltration and Residual Chlorination as a Decentralized Water Treatment Strategy for Ten Rural Healthcare Facilities in Rwanda.

    PubMed

    Huttinger, Alexandra; Dreibelbis, Robert; Roha, Kristin; Ngabo, Fidel; Kayigamba, Felix; Mfura, Leodomir; Moe, Christine

    2015-10-01

    There is a critical need for safe water in healthcare facilities (HCF) in low-income countries. HCF rely on water supplies that may require additional on-site treatment, and need sustainable technologies that can deliver sufficient quantities of water. Water treatment systems (WTS) that utilize ultrafiltration membranes for water treatment can be a useful technology in low-income countries, but studies have not systematically examined the feasibility of this technology in low-income settings. We monitored 22 months of operation of 10 WTS, including pre-filtration, membrane ultrafiltration, and chlorine residual disinfection that were donated to and operated by rural HCF in Rwanda. The systems were fully operational for 74% of the observation period. The most frequent reasons for interruption were water shortage (8%) and failure of the chlorination mechanism (7%). When systems were operational, 98% of water samples collected from the HCF taps met World Health Organization (WHO) guidelines for microbiological water quality. Water quality deteriorated during treatment interruptions and when water was stored in containers. Sustained performance of the systems depended primarily on organizational factors: the ability of the HCF technician to perform routine servicing and repairs, and environmental factors: water and power availability and procurement of materials, including chlorine and replacement parts in Rwanda. PMID:26516883

  3. Evaluation of Membrane Ultrafiltration and Residual Chlorination as a Decentralized Water Treatment Strategy for Ten Rural Healthcare Facilities in Rwanda

    PubMed Central

    Huttinger, Alexandra; Dreibelbis, Robert; Roha, Kristin; Ngabo, Fidel; Kayigamba, Felix; Mfura, Leodomir; Moe, Christine

    2015-01-01

    There is a critical need for safe water in healthcare facilities (HCF) in low-income countries. HCF rely on water supplies that may require additional on-site treatment, and need sustainable technologies that can deliver sufficient quantities of water. Water treatment systems (WTS) that utilize ultrafiltration membranes for water treatment can be a useful technology in low-income countries, but studies have not systematically examined the feasibility of this technology in low-income settings. We monitored 22 months of operation of 10 WTS, including pre-filtration, membrane ultrafiltration, and chlorine residual disinfection that were donated to and operated by rural HCF in Rwanda. The systems were fully operational for 74% of the observation period. The most frequent reasons for interruption were water shortage (8%) and failure of the chlorination mechanism (7%). When systems were operational, 98% of water samples collected from the HCF taps met World Health Organization (WHO) guidelines for microbiological water quality. Water quality deteriorated during treatment interruptions and when water was stored in containers. Sustained performance of the systems depended primarily on organizational factors: the ability of the HCF technician to perform routine servicing and repairs, and environmental factors: water and power availability and procurement of materials, including chlorine and replacement parts in Rwanda. PMID:26516883

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

    PubMed

    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

  5. Optimisation of an integrated optical evanescent wave absorbance sensor for the determination of chlorinated hydrocarbons in water.

    PubMed

    Mayer, J; Bürck, J; Ache, H J

    1996-03-01

    The suitability of an integrated optical chemical sensor for the determination of highly volatile chlorinated hydrocarbons in aqueous solutions has been proven. The analytes are detected by NIR absorption spectrometry in the evanescent field of an integrated optical strip waveguide generated in a BGG31 (Schott, Germany) glass substrate, which is coated with a hydrophobic polymer superstrate as sensing layer. It has been shown that the sensitivity increases when the refractive index of the superstrate is increased from 1.333 up to 1.46. Different UV-cured polysiloxanes with low cross sensitivity to water have been prepared. Due to the good light transmission properties of the IO-sensors prepared by this method, quantitative measurements have been performed with the model system trichloroethene (TCE) in water. A detection limit of 22 ppm has been found and the sensor response times (t(90)-value) are between five and fourteen minutes for a coating thickness of around 30 microm. The sensor response is totally reversible. The analyte desorbes in air within 2 min. The enrichment of trichloroethene in the polysiloxane coating can be described by film diffusion through the aqueous boundary layer as rate determining step. PMID:15048399

  6. Monitoring the effect of poplar trees on petroleum-hydrocarbon and chlorinated-solvent contaminated ground water

    USGS Publications Warehouse

    Landmeyer, J.E.

    2001-01-01

    At contaminated groundwater sites, poplar trees can be used to affect groundwater levels, flow directions, and ultimately total groundwater and contaminant flux to areas downgradient of the trees. The magnitude of the hydrologic changes can be monitored using fundamental concepts of groundwater hydrology, in addition to plant physiology-based approaches, and can be viewed as being almost independent of the contaminant released. The affect of poplar trees on the fate of groundwater contaminants, however, is contaminant dependent. Some petroleum hydrocarbons or chlorinated solvents may be mineralized or transformed to innocuous compounds by rhizospheric bacteria associated with the tree roots, mineralized or transformed by plant tissues in the transpiration stream or leaves after uptake, or passively volatilized and rapidly dispersed or oxidized in the atmosphere. These processes also can be monitored using a combination of physiological- or geochemical-based field or laboratory approaches. When combined, such hydrologic and contaminant monitoring approaches can result in a more accurate assessment of the use of poplar trees to meet regulatory goals at contaminated groundwater sites, verify that these goals continue to be met in the future, and ultimately lead to a consensus on how the performance of plant-based remedial strategies (phytoremediation) is to be assessed.

  7. Impact of carbon, oxygen and sulfur content of microscale zerovalent iron particles on its reactivity towards chlorinated aliphatic hydrocarbons.

    PubMed

    Velimirovic, Milica; Larsson, Per-Olof; Simons, Queenie; Bastiaens, Leen

    2013-11-01

    Zerovalent iron (ZVI) abiotically degrades several chlorinated aliphatic hydrocarbons (CAHs) via reductive dechlorination, which offers perspectives for in situ groundwater remediation applications. The difference in reactivity between ZVI particles is often linked with their specific surface area. However, other parameters may influence the reactivity as well. Earlier, we reported for a set of microscale zerovalent iron (mZVI) particles the disappearance kinetic of different CAHs which were collected under consistent experimental conditions. In the present study, these kinetic data were correlated with the carbon, oxygen and sulfur content of mZVI particles. It was confirmed that not only the specific surface area affects the disappearance kinetic of CAHs, but also the chemical composition of the mZVI particles. The chemical composition, in addition, influences CAHs removal mechanism inducing sorption onto mZVI particles instead of dechlorination. Generally, high disappearance kinetic of CAHs was observed for particles containing less oxygen. A high carbon content, on the other hand, induced nonreactive sorption of the contaminants on the mZVI particles. To obtain efficient remediation of CAHs by mZVI particles, this study suggested that the carbon and oxygen content should not exceed 0.5% and 1% respectively. Finally, the efficiency of the mZVI particles may be improved to some extent by enriching them with sulfur. However, the impact of sulfur content on the reactivity of mZVI particles is less pronounced than that of the carbon and oxygen content. PMID:23962383

  8. Comparison of purge and trap GC/MS and purgeable organic chloride analysis for monitoring volatile chlorinated hydrocarbons

    USGS Publications Warehouse

    Barber, Larry B.; Thurman, E. Michael; Takahashi, Yoshi; Noriega, Mary C.

    1992-01-01

    A combined field and laboratory study was conducted to compare purge and trap gas chromatography/mass spectrometry (PT-GC/MS) and purgeable organic chloride (POCl) analysis for measuring volatile chlorinated hydrocarbons (VCH) in ground water. Distilled-water spike and recovery experiments using 10 VCH indicate that at concentrations greater than 1 ??g/l recovery is more than 80 percent for both methods with relative standard deviations of about 10 percent. Ground-water samples were collected from a site on Cape Cod, Massachusetts, where a shallow unconfined aquifer has been contaminated by VCH, and were analyzed by both methods. Results for PT-GC/MS and POCl analysis of the ground-water samples were not significantly different (alpha = 0.05, paired t-test analysis) and indicated little bias between the two methods. Similar conclusions about concentrations and distributions of VCH in the ground-water contamination plume were drawn from the two data sets. However, only PT-GC/MS analysis identified the individual compounds present and determined their concentrations, which was necessary for toxicological and biogeochemical evaluation of the contaminated ground water. POCl analysis was a complimentary method for use with PT-GC/MS analysis for identifying samples with VCH concentrations below the detection limit or with high VCH concentrations that require dilution. Use of POCl as a complimentary monitoring method for PT-GC/MS can result in more efficient use of analytical resources.

  9. Identifying sources of chlorinated aliphatic hydrocarbons in a residential area in Italy using the integral pumping test method

    NASA Astrophysics Data System (ADS)

    Alberti, Luca; Lombi, Silvia; Zanini, Andrea

    2011-09-01

    The results of integral pumping tests (IPTs) performed in the city of Fabriano, Italy, are presented. The IPT methodology was developed by the European Union project INCORE, as a tool for groundwater investigation and source localization in contaminated areas. This methodology consists of a multiple-well pumping test in which the wells are positioned along a control plane downstream of suspected contaminant source zones and perpendicular to the mean groundwater flow direction. During the pumping, concentration time series of target contaminants are measured. In Fabriano, two control planes were realized to identify a chlorinated aliphatic hydrocarbon plume, to estimate the mass fluxes and draw up a ranked list of the main contamination sources. A numerical flow model was implemented to support the IPT design and to interpret the results. This study revealed low-level trichloroethylene contamination (concentration below 8 μg/l), tetrachloroethylene contamination (mean concentration up to 500 μg/l) and a mass flow rate of about 300 g/day. Through the application of the IPT method, the mean contaminant concentrations, the spatial distribution of concentration values along the control planes, and the total contaminant mass flow rates were evaluated, and the investigation area was reduced for further and deeper investigation activities.

  10. Hydrocarbons in oil residues on beaches of islands of Prince William Sound, Alaska

    USGS Publications Warehouse

    Kvenvolden, K.A.; Hostettler, F.D.; Rapp, J.B.; Carlson, P.R.

    1993-01-01

    Aliphatic and aromatic hydrocarbons were measured on oil residues from beaches on six islands in Prince William Sound, Alaska. In addition to altered products from the Exxon Valdez oil spill of 1989, we also found, at two widely separated locations, residues that are similar to each other but chemically distinct from the spilled oil. Terpanes, steranes, monoaromatic steranes, and carbon isotopic compositions of total extracts were most useful in correlating the altered products of the spilled oil. These same parameters revealed that the two non-Valdez samples are likely residues of oil originally produced in California. The results indicate that oil residues currently on the beaches of this estuary have at least two quite different origins.

  11. Residues of organochlorine pesticides and polycyclic aromatic hydrocarbons in drinking water of Ahmedabad City, India

    SciTech Connect

    Jani, J.P.; Mistry, J.S. ); Raiyani, C.V.; Patel, J.S.; Desai, N.M.; Kashyap, S.K. )

    1991-09-01

    The ubiquitous environmental pollutants organochlorine pesticides (OCP) and polycyclic aromatic hydrocarbons (PAH) have been extensively studied for their toxicity. Monitoring of OCP and PAH residues has always been considered important for controlling human exposure. As compared to several other countries, the higher body burden of OCP in Indian general population is indicative of higher exposure to these chemicals. Recent studies have shown higher residues of OCP in food commodities including human mother's milk. The levels of OCP in drinking water is still a matter of concern and practically nothing is known about the residues of PAH in drinking water in India. This is the first report of its kind regarding the residues of OCP and PAH in drinking water of Ahmedabad City, the sixth largest city of India with a population of more than 2.5 million.

  12. Genetic Engineering of Plants to Improve Phytoremediation of Chlorinated Hydrocarbons in Groundwater

    SciTech Connect

    Strand, Stuart E.

    2004-12-01

    I. Mechanism of halogenated hydrocarbon oxidation We are using poplar culture cells to determine the pathway of TCE metabolism. In our earlier work, we found that trichloroethanol (TCEOH) is a major early intermediate. Our studies this year have focused on the steps that follow this toxic intermediate. We did several experiments to track the disappearance of TCEOH after the cells were removed from TCE. We could conclude that TCEOH is not an end-product but is rapidly degraded. Six flasks of poplar liquid suspension cells were exposed to a level of 50 {micro}g/ml TCE for three days. Three of the cultures were subjected to MTBE extractions to quantify the levels of TCEOH produced. The cells of the remaining three cultures were then pelleted and resuspended in fresh medium. After three more days, these were also subjected to MTBE extractions. The samples were analyzed by GC-ECD. After the three days of further metabolism, an average of 91% of the trichloroethanol was gone. When similar experiments were done with intact plants and both free and conjugated TCEOH were quantified, a similar rapid decline in both forms was seen (Shang, 2001). Therefore, it seems probable that similar mechanisms are taking place in both poplar suspension cells and whole poplar plants, so we continued to do our studies with the suspension cells. Metabolism of trichloroethanol may go through trichloroacetic acid (TCAA) prior to dehalogenation. To test this possibility, we exposed cells to TCE and analyzed for TCAA over time. The cultures were analyzed after 4, 5, 6, and 14 days from TCE exposure. We did not detect any significant amount of TCAA above the background in undosed cells. To determine if trichloroethanol itself is directly dehalogenated, we analyzed TCE-exposed cells for the presence of dichloroethanol. Undosed cells did not have any of the DCEOH peak but TCE-dosed cells that produced the highest levels of trichloroethanol did have a small DCEOH peak. Cultures that did not produce

  13. In Vitro Transformation of Chlorinated Parabens by the Liver S9 Fraction: Kinetics, Metabolite Identification, and Aryl Hydrocarbon Receptor Agonist Activity.

    PubMed

    Terasaki, Masanori; Wada, Takeshi; Nagashima, Satoshi; Makino, Masakazu; Yasukawa, Hiro

    2016-01-01

    We investigated the kinetics of in vitro transformation of a dichlorinated propyl paraben (2-propyl 3,5-dichloro-4-hydroxybenzoate; Cl2PP) by the rat liver S9 fraction and assessed the aryl hydrocarbon receptor (AhR) agonist activity of the metabolite products identified in HPLC and GC/MS analysis and by metabolite syntheses. The results indicated that the chlorination of Cl2PP reduced its degradation rate by approximately 40-fold. Two hydroxylated metabolite products showed AhR agonist activity of up to 39% of that of the parent Cl2PP when assessed in a yeast (YCM3) reporter gene assay. The determination of the metabolic properties of paraben bioaccumulation presented here provides further information on the value of risk assessments of chlorinated parabens as a means to ensure human health and environmental safety. PMID:27250800

  14. Residues of petroleum hydrocarbons in tissues of sea turtles exposed to the IXTOC I oil spill

    USGS Publications Warehouse

    Hall, R.J.; Belisle, A.A.; Sileo, L.

    1983-01-01

    Sea turtles found dead when the Ixtoc I oil spill reached Texas waters were necropsied and tissues were analyzed for residues of petroleum hydrocarbons. Two of the three turtles were in poor flesh, but had no apparent oil-caused lesions. There was evidence of oil in all tissues examined and indications that the exposure had been chronic. Comparisons with results of studies done on birds indicate consumption of 50,000 ppm or more of oil in the diet. Some possible mechanisms of mortality are suggested.

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

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

    -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).

  16. SERUM ORGANOCHLORINE RESIDUES IN FLORIDA CITRUS WORKERS COMPARED TO THE NATIONAL HEALTH AND NUTRITION EXAMINATION SURVEY SAMPLE

    EPA Science Inventory

    The monitoring of organochloride residues is important because they have a propensity to accumulate in the tissues of man and animals. All chlorinated hydrocarbon insecticides can be absorbed through dermal, oral, and respiratory routes. Storage is determined primarily by metabol...

  17. A Model to Predict Total Chlorine Residue in the Cooling Seawater of a Power Plant Using Iodine Colorimetric Method

    PubMed Central

    Wang, Jih-Terng; Chen, Ming-Hui; Lee, Hung-Jen; Chang, Wen-Been; Chen, Chung-Chi; Pai, Su-Cheng; Meng, Pei-Jie

    2008-01-01

    A model experiment monitoring the fate of total residue oxidant (TRO) in water at a constant temperature and salinity indicated that it decayed exponentially with time, and with TRO decaying faster in seawater than in distilled water. The reduction of TRO by temperature (°K) was found to fit a curvilinear relationship in distilled water (r2 = 0.997) and a linear relationship in seawater (r2 = 0.996). Based on the decay rate, flow rate, and the length of cooling water flowing through at a given temperature, the TRO level in the cooling water of a power plant could be estimated using the equation developed in this study. This predictive model would provide a benchmark for power plant operators to adjust the addition of chlorine to levels necessary to control bio-fouling of cooling water intake pipelines, but without irritating ambient marine organisms. PMID:19325768

  18. Lysine residues direct the chlorination of tyrosines in YXXK motifs of apolipoprotein A-I when hypochlorous acid oxidizes high density lipoprotein.

    PubMed

    Bergt, Constanze; Fu, Xiaoyun; Huq, Nabiha P; Kao, Jeff; Heinecke, Jay W

    2004-02-27

    Oxidized lipoproteins may play an important role in the pathogenesis of atherosclerosis. Elevated levels of 3-chlorotyrosine, a specific end product of the reaction between hypochlorous acid (HOCl) and tyrosine residues of proteins, have been detected in atherosclerotic tissue. Thus, HOCl generated by the phagocyte enzyme myeloperoxidase represents one pathway for protein oxidation in humans. One important target of the myeloperoxidase pathway may be high density lipoprotein (HDL), which mobilizes cholesterol from artery wall cells. To determine whether activated phagocytes preferentially chlorinate specific sites in HDL, we used tandem mass spectrometry (MS/MS) to analyze apolipoprotein A-I that had been oxidized by HOCl. The major site of chlorination was a single tyrosine residue located in one of the protein's YXXK motifs (where X represents a nonreactive amino acid). To investigate the mechanism of chlorination, we exposed synthetic peptides to HOCl. The peptides encompassed the amino acid sequences YKXXY, YXXKY, or YXXXY. MS/MS analysis demonstrated that chlorination of tyrosine in the peptides that contained lysine was regioselective and occurred in high yield if the substrate was KXXY or YXXK. NMR and MS analyses revealed that the N(epsilon) amino group of lysine was initially chlorinated, which suggests that chloramine formation is the first step in tyrosine chlorination. Molecular modeling of the YXXK motif in apolipoprotein A-I demonstrated that these tyrosine and lysine residues are adjacent on the same face of an amphipathic alpha-helix. Our observations suggest that HOCl selectively targets tyrosine residues that are suitably juxtaposed to primary amino groups in proteins. This mechanism might enable phagocytes to efficiently damage proteins when they destroy microbial proteins during infection or damage host tissue during inflammation. PMID:14660678

  19. EXPECTED EFFECTS OF RESIDUAL CHLORINE AND NITROGEN IN SEWAGE EFFLUENT ON THE ESTUARINE ECOSYSTEM OF GREENWICH COVE, RI: AN ENERGY SYSTEMS AND RISK ASSESSMENT OF EFFECTS

    EPA Science Inventory

    Physical, toxicological, and energy systems modeling were combined to make estimates of likely ecosystem-level effects due to residual chlorine in sewage effluent. The energy systems model also allowed us to make estimates of the effects of nutrient loading on the estuary both se...

  20. Determination of chlorinated pesticide residues in foods. II. Simultaneous analysis of chlorinated pesticide and phthalate ester residues by using AgNO3-coated Florisil column chromatography for cleanup of various samples.

    PubMed

    Suzuki, T; Ishikawa, K; Sato, N; Sakai, K I

    1979-05-01

    A simplified method suitable for simultaneous analysis of chlorinated pesticide and phthalate ester residues in various foods was developed. Chemical residues were quantitatively extracted from fatty and vegetable samples with acetonitrile as follows: Chemical standard in 0.5 mL ethanol solution was added to 10 g homogenized sample. After 3 hr, pork and beef were extracted 3 times with 20 mL portions of acetonitrile. The acetonitrile layers were diluted with water and extracted with n-hexane. Rice samples were combined with 10 mL water, 5 mL acetonitrile and 1 mL ethanol and extracted 3 times with 20 mL portions of n-hexane. The n-hexane concentrate from each sample was submitted to AgNO3-coated Florisil column chromatography. The AgNO3 coating adequately adsorbed interfering coextractives. Extracts of fish and vegetable samples were separated into 2 fractions by the above column chromatography. Supplemental cleanup procedures were also developed to accurately determine phthalate esters eluted in the second fraction. Satisfactory gas chromatograms were obtained for most samples. PMID:479097

  1. Heavy metal and hydrocarbon residues in tissue and blood of beef steers bedded on waste newspapers

    SciTech Connect

    Comerford, J.W.

    1992-07-01

    There are over 3 million tons of waste newspaper generated annually in Pennsylvania alone. This provides a significant disposal problem for many municipalities who are confronted with dwindling options for solid waste disposal. Previous studies have identified several of the potential advantages of the material as a bedding material for livestock. With over 1 million beef and dairy cattle in the state, the potential use of newspaper as bedding is important. Of concern, however, is the effect of the chemical composition of the paper on animals which have the opportunity to consume it, and subsequent entry of undesirable residues into the food chain. Metals such as cadmium, lead, mercury and copper are known to exist in relatively high quantities in newsprint from the ink used in printing. Naphthalene and other aromatic hydrocarbons which are found in coal tar and synthetic and natural crude oils are known to accumulate in marine life and are absorbed by humans after consumption. A preliminary report indicated beef steers bedded on newspaper did consume varying amounts of the material. Few studies have determined if residues of heavy metals or organic compounds are found in the carcasses of animals continuously bedded on newspaper. The objectives of this study were to determine the levels of cadmium, copper, lead, mercury and certain aromatic hydrocarbons in the blood and liver of feedlot cattle bedded continuously on waste newspaper or sawdust. 4 refs., 3 tabs.

  2. Distributions and fate of chlorinated pesticides, biomarkers and polycyclic aromatic hydrocarbons in sediments along a contamination gradient from a point-source in San Francisco Bay, California

    USGS Publications Warehouse

    Pereira, W.E.; Hostettler, F.D.; Rapp, J.B.

    1996-01-01

    The distribution and fate of chlorinated pesticides, biomarkers, and polycyclic aromatic hydrocarbons (PAHs) in surficial sediments along a contamination gradient in the Lauritzen Canal and Richmond Harbor in San Francisco Bay was investigated. Compounds were identified and quantified using gas chromatography-ion trap mass spectrometry. Biomarkers and PAHs were derived primarily from weathered petroleum. DDT was reductively dechlorinated under anoxic conditions to DDD and several minor degradation products, DDMU, DDMS, and DDNU. Under aerobic conditions, DDT was dehydrochlorinated to DDE and DBP. Aerobic degradation of DDT was diminished or inhibited in zones of high concentration, and increased significantly in zones of lower concentration: Other chlorinated pesticides identified in sediment included dieldrin and chlordane isomers. Multivariate analysis of the distributions of the DDTs suggested that there are probably two sources of DDD. In addition, DDE and DDMU are probably formed by similar mechanisms, i.e. dehydrochlorination. A steep concentration gradient existed from the Canal to the Outer Richmond Harbor, but higher levels of DDD than those found in the remainder of the Bay indicated that these contaminants are transported on particulates and colloidal organic matter from this source into San Francisco Bay. Chlorinated pesticides and PAHs may pose a potential problem to biota in San Francisco Bay.

  3. Environmental analysis of chlorinated and brominated polycyclic aromatic hydrocarbons by comprehensive two-dimensional gas chromatography coupled to high-resolution time-of-flight mass spectrometry.

    PubMed

    Ieda, Teruyo; Ochiai, Nobuo; Miyawaki, Toshifumi; Ohura, Takeshi; Horii, Yuichi

    2011-05-27

    A method for the analysis of chlorinated and brominated polycyclic aromatic hydrocarbon (Cl-/Br-PAHs) congeners in environmental samples, such as a soil extract, by comprehensive two-dimensional gas chromatography coupled to a high resolution time-of-flight mass spectrometry (GC×GC-HRTOF-MS) is described. The GC×GC-HRTOF-MS method allowed highly selective group type analysis in the two-dimensional (2D) mass chromatograms with a very narrow mass window (e.g. 0.02Da), accurate mass measurements for the full mass range (m/z 35-600) in GC×GC mode, and the calculation of the elemental composition for the detected Cl-/Br-PAH congeners in the real-world sample. Thirty Cl-/Br-PAHs including higher chlorinated 10 PAHs (e.g. penta, hexa and hepta substitution) and ClBr-PAHs (without analytical standards) were identified with high probability in the soil extract. To our knowledge, highly chlorinated PAHs, such as C(14)H(3)Cl(7) and C(16)H(3)Cl(7), and ClBr-PAHs, such as C(14)H(7)Cl(2)Br and C(16)H(8)ClBr, were found in the environmental samples for the first time. Other organohalogen compounds; e.g. polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs), and polychlorinated dibenzofurans (PCDFs) were also detected. This technique provides exhaustive analysis and powerful identification for the unknown and unconfirmed Cl-/Br-PAH congeners in environmental samples. PMID:21316690

  4. Chlorinated hydrocarbons and mercury in sediments, red-winged blackbirds (Agelaius phoeniceus) and tree swallows (Tachycineta bicolor) from wetlands in the Great Lakes-St. Lawrence River basin

    SciTech Connect

    Bishop, C.A.; Koster, M.D.; Chek, A.A.; Hussell, D.J.T.; Jock, K.

    1995-03-01

    In 1991, the authors collected red-winged blackbird (Agelauis phoeniceus) eggs and tree swallow (Tachycineta bicolor) eggs and nestlings, and sediment samples from 2 wetland sites in the Great lakes and St. Lawrence River basin. They analyzed for chlorinated hydrocarbons and total mercury and found that biota contained contaminant concentrations which were one to two orders of magnitude above those in sediments. Maximum concentrations of contaminants were found in Akwesasne, St. Lawrence river (PCBs = 18,558.8 ng/g in red-winged blackbird eggs, oxychlordane = 58.8/g and mirex = 40.1 ng/g in tree swallow eggs); Mud Creek, Lake Erie and Cootes Paradise. Despite the migratory habits of red-winged blackbirds and tree swallows, agreement among biota and sediment in geographic variation of contaminant concentrations supports the use of these animals as biomonitors of persistent chemicals. Although chlorinated hydrocarbon concentrations in red-winged blackbird eggs were significantly correlated with sediment contamination, the local nature of the tree swallow chick diet suggests that nestlings would be the best indicator of local contaminant trends.

  5. Electrochemical continuous decomposition of chloroform and other volatile chlorinated hydrocarbons in water using a column type metal impregnated carbon fiber electrode

    SciTech Connect

    Sonoyama, Noriyuki; Sakata, Tadayoshi

    1999-10-01

    Trihalomethane and other chlorinated hydrocarbons are known to be toxic to human health. However, removal of these compounds from water is not easy. The authors attempted continuous electrochemical decomposition of chloroform that is the main compound of trihalomethanes and some toxic chlorinated hydrocarbons in water using a metal-impregnated CFE, concentration of chloroform in 0.5 M K{sub 2}SO{sub 4} (the supporting electrolyte) solution was decreased from 0.23m mol/L to below the limit of detection of their analysis system (1 ppm) at a flow rate of 1 mL/min. The main product of electrolysis was methane. This high efficiency, determined by the chemical yield, hardly changed at a flow rate of 20 mL/min at a Ag-impregnated CFE. At a flow rate of 1 mL/min, chloroform was degraded with a decomposition efficiency of almost 100% even in the solution without the supporting electrolyte, whereas at a higher flow rate, the efficiency for the decomposition of chloroform decreased with a decrease in the concentration of the supporting electrolyte. Tetrachloroethylene, 1,1,1-trichloroethane, and 1,1,2-trichloroethane were also decomposed at a Ag-impregnated CFE with an efficiency of almost 100%.

  6. CHLORINATED SOLVENT CONTAMINATED SOILS AND GROUNDWATER: FIELD APPLICATION OF THE SOLVENT EXTRACTION RESIDUAL BIOTREATMENT TECHNOLOGY

    EPA Science Inventory

    A pilot scale demonstration of the Solvent Extraction Residual Biotreatment (SERB) technology was conducted at the former Sage's Dry Cleaner site in Jacksonville, FL. The SERB technology is a treatment train approach to complete site restoration, which combines an active in situ...

  7. The Reaction Specificity of Nanoparticles in Solution: Application to the Reaction of Nanoparticulate Iron and Iron-Bimetallic Compounds with Chlorinated Hydrocarbons and Oxyanions

    SciTech Connect

    2005-06-01

    The prospect for better remediation technologies using nanoparticles of iron, iron oxides, and iron with catalytic metals (i.e., bimetallics) has potentially transformative implications for environmental management of DOE sites across the country. Of particular interest is the potential to avoid undesirable products from the degradation of chlorinated solvents by taking advantage of the potential selectivity of nanoparticles to produce environmentally benign products from CCl{sub 4}. Chlorinated solvents are the most frequently reported subsurface contaminants across the whole DOE complex, and carbon tetrachloride (CCl{sub 4}) is the chlorinated solvent that is of greatest concern at Hanford (U. S. Department Energy 2001). In evaluating technologies that might be used at the site, a critical concern will be that CCl{sub 4} reduction usually occurs predominantly by hydrogenolysis to chloroform (CHCl{sub 3}) and methylene chloride (CH{sub 2}Cl{sub 2}), both of which are nearly as problematic as CCl{sub 4} (National Research Council, 1978). Competing reaction pathways produce the more desirable products carbon monoxide (CO) and/or formate (HCOO{sup -}), and possibly CO{sub 2}, but the proportion of reaction that occurs by these pathways is highly variable. Iron-based metallic and oxide nanoparticles have been shown to have enhanced reactivity towards a variety of chemical species, including chlorinated hydrocarbons and reducible oxyanions. Possibly of greater importance is the ability of nanoparticles to select for specific reaction products, potentially facilitating the formation of more environmentally acceptable products. The purpose of this study is to develop a fundamental understanding of the mechanism responsible for the overall particle reactivity and reaction selectivity of reactive metal and oxide nanoparticles. To achieve this objective the project involves the synthesis (using solution and vacuum synthesis methods) and characterization of well

  8. Chlorinated dibenzo-p-dioxin and dibenzofuran residue levels in food. Final report

    SciTech Connect

    Stanley, J.S.; Bauer, K.M.

    1989-10-26

    The chemical analysis of selected foods was conducted to provide an estimate of the residue levels of PCDDs and PCDFs. The foodstuffs included saltwater fish, freshwater fish, beef, chicken, pork, bovine milk, and eggs. The foodstuffs were collected from San Francisco and Los Angeles. Emphasis was placed on the collection of foodstuffs of California origin. Individual foods collected from multiple sites within San Francisco and Los Angeles were composited for analysis of the residue levels. Detectable levels of PCDDs and PCDFs were identified in all but the egg samples that were analyzed. Overall, the freshwater fish composites were found to have the highest incidence of detectable levels. The order of highest to lowest incidence of detection follows: freshwater fish > saltwater fish > pork and chicken > beef and milk > eggs. All data were generated from a sample size of approximately 10 g of extractable fatty materials. All data are presented to reflect lipid or fat concentrations such that extrapolation with other data bases can be achieved.

  9. A New On-Line Detecting Apparatus of the Residual Chlorine in Disinfectant for Fresh-Cut Vegetables

    NASA Astrophysics Data System (ADS)

    Hu, Chao; Su, Shu-Qiang; Li, Bao-Guo; Liu, Meng-Fang

    With the fast development of modern food and beverage industry, fresh-cut vegetables have wider application than before. During the process of sterilization in fresh-cut vegetables, the concentration of chloric disinfectant is usually so high that the common sensor can't be used directly on the product line. In order to solve this problem, we have invented a new detecting apparatus which could detect high concentration of chloric disinfectant directly. In this paper, the working principle, main monitor indicators, application and technical creations of the on-line apparatus have been discussed, and we also carried on the experimental analysis for its performance. The actual demands in factory could be met when the detecting flux is 2L/min, the dilution ratio is 15 and input amount of the disinfectant is 200ml per time, the max of the detecting deviation achieves ±4.8ppm(mg/L). The main detecting range of residual chlorine is 0~300ppm.

  10. EVALUATION OF FUSED-SILICA CAPILLARY COLUMNS FOR GC/ECD (GAS CHROMATOGRAPHY WITH ELECTRON CAPTURE DETECTION) ANALYSIS OF CHLORINATED HYDROCARBONS LISTED IN EPA (ENVIRONMENTAL PROTECTION AGENCY) METHOD 8120 (JOURNAL VERSION)

    EPA Science Inventory

    Four mega-bore, one wide-bore, and one narrow-bore fused-silica capillary columns were evaluated for their applicability to the GC/ECD analysis of 22 chlorinated hydrocarbons, some of which are currently targeted by EPA Method 8120. No one column can resolve all 22 compounds. Fou...

  11. Polycyclic Aromatic Hydrocarbon Residues in Serum Samples of Autopsied Individuals from Tennessee

    PubMed Central

    Ramesh, Aramandla; Kumar, Anil; Aramandla, Mounika P.; Nyanda, Alfred M.

    2014-01-01

    This study reports the concentrations of Polycyclic Aromatic Hydrocarbons (PAHs) in human blood sera samples (n = 650) obtained at autopsy from individuals who died of drug abuse, alcohol toxicity, homicide, suicide and other unknown causes. The analyzed samples from decedents revealed the presence of PAHs of which B(a)P was the most predominant one, followed by benzo(b)fluoranthene and benzo(k)fluoranthene. The other PAHs detected sporadically and measured were benzo(g,h,i)perylene, acenaphthene, anthracene, phenanthrene, and fluoranthene The mean concentrations of PAHs were greater in the twenties to fifties age groups compared to others. The PAH residue levels detected were high in African Americans compared to Caucasians, Asians, and Hispanics. It appears that environmental exposure, dietary intake and in some cases occupational exposure may have contributed to the PAH body burden. While the PAH residue concentrations measured fall within the range of those reported for healthy adults elsewhere, in isolated cases, the concentrations detected were high, calling the need for a reduction in PAH emissions and human biomonitoring studies for purposes of risk assessment. PMID:25547400

  12. Biodegradation pattern of hydrocarbons from a fuel oil-type complex residue by an emulsifier-producing microbial consortium.

    PubMed

    Nievas, M L; Commendatore, M G; Esteves, J L; Bucalá, V

    2008-06-15

    The biodegradation of a hazardous waste (bilge waste), a fuel oil-type complex residue from normal ship operations, was studied in a batch bioreactor using a microbial consortium in seawater medium. Experiments with initial concentrations of 0.18 and 0.53% (v/v) of bilge waste were carried out. In order to study the biodegradation kinetics, the mass of n-alkanes, resolved hydrocarbons and unresolved complex mixture (UCM) hydrocarbons were assessed by gas chromatography (GC). Emulsification was detected in both experiments, possibly linked to the n-alkanes depletion, with differences in emulsification start times and extents according to the initial hydrocarbon concentration. Both facts influenced the hydrocarbon biodegradation kinetics. A sequential biodegradation of n-alkanes and UMC was found for the higher hydrocarbon content. Being the former growth associated, while UCM biodegradation was a non-growing process showing enzymatic-type biodegradation kinetics. For the lower hydrocarbon concentration, simultaneous biodegradation of n-alkanes and UMC were found before emulsification. Nevertheless, certain UCM biodegradation was observed after the medium emulsification. According to the observed kinetics, three main types of hydrocarbons (n-alkanes, biodegradable UCM and recalcitrant UCM) were found adequate to represent the multicomponent substrate (bilge waste) for future modelling of the biodegradation process. PMID:17997031

  13. A comparison of the concentrations of certain chlorinated hydrocarbons and polychlorinated biphenyls in bone marrow and fat tissue of children and their concentrations in breast milk

    SciTech Connect

    Scheele, J.; Teufel, M.; Niessen, K.H.

    1995-12-31

    Chlorinated hydrocarbon (CHC) and polychlorinated biphenyl (PCB) concentrations in the bone marrow of 57 children were compared with the concentrations in adipose tissue of 50 children and the concentrations in breast milk in the Federal Republic of Germany from 1984 to 1991. The concentrations of hexachlorobenzene (HCB), the dichlorodiphenyl-trichlorethane (DDT)-metabolites, and polychlorinated biphenyl (PCB) congeners no. 138 and no. 153 were increased threefold, while the concentrations of several hexachloro-cyclohexane (HCH)-isomers and PCB congener no. 180 were only increased two fold. Because breast feeding is the primary source of CHC and PCB in toddlers and infants we also compared the concentrations in bone marrow of children with the concentrations in breast milk and found approximately fourfold higher concentrations for the most highly chlorinated PCB congener no. 180, but only threefold higher concentrations for PCB 138 and 153 and the DDT-metabolites. The concentrations of {beta}-HCH and HCB were only slightly higher in bone marrow. 15 refs., 2 figs.

  14. Experimental and theoretical studies into the formation of C4-C6 products in partially chlorinated hydrocarbon pyrolysis systems: a probabilistic approach to congener-specific yield predictions.

    PubMed

    McIntosh, Grant J; Russell, Douglas K

    2014-09-25

    This work presents a study of the pyrolytic formation of vinylacetylene and benzene congeners formed from chlorinated hydrocarbon precursors, a complex, multipath polymerization system formed in a monomer-rich environment. (Co-)pyrolyses of dichloro- and trichloroethylene yield a rich array of products, and assuming a single dominant underlying growth mechanism, this (on comparing expected and observed products) allows a number of potentially competing channels to C4 and C6 products to be ruled out. Poor congener/isomer descriptions rule out even-carbon radical routes, and the absence of C3 and C5 products rule out odd-carbon processes. Vinylidenes appear unable to describe the increased reactivity of acetylenes with chlorination noted in our experiments, leaving molecular acetylene dimerization processes and, in C6 systems, the closely related Diels-Alder cyclization as the likely reaction mechanism. The feasibility of these routes is further supported by ab initio calculations. However, some of the most persuasive evidence is provided by congener-specific yield predictions enabled by the construction of a probability tree analogue of kinetic modeling. This approach is relatively quick to construct, provides surprisingly accurate predictions, and may be a very useful tool in screening for important reaction channels in poorly understood congener- or isomer-rich reaction systems. PMID:25225996

  15. Polycyclic aromatic hydrocarbon (PAH) residues on skin in relation to air levels among roofers

    SciTech Connect

    Wolff, M.S.; Herbert, R.; Marcus, M.; Rivera, M.; Landrigan, P.J.; Andrews, L.R.

    1989-05-01

    To assess the utility of skin wipes as an index of exposure to polycyclic aromatic hydrocarbons (PAHs), simultaneous skin wipe and breathing zone air samples were obtained for 10 roofers. Samples were obtained during removal of an old coal-tar pitch roof and application of a new asphalt roof. Skin wipes were obtained immediately before and after the workshift. Anthracene was present in air but not skin samples. In air samples, the relative concentrations of seven PAHs were fluoranthene greater than pyrene greater than benzanthracene greater than benzo(a)pyrene greater than benzo(b)fluoranthene greater than benzo(ghi)perylene greater than benzo(k)fluoranthene. A similar pattern, or rank concentration, was observed in matching skin wipe samples. The amount (ng) of PAH (either total or individual compounds) found in skin wipes taken after the workday was significantly correlated with that in air samples (micrograms/m3, time-weighted average) for 8 of the 9 cases with air and skin samples taken the same day (r = 0.99 for total PAH). Skin wipe PAH residues were not significantly correlated with air samples taken 4 d earlier. These findings suggest that skin wipes can provide a useful measure of exposure to PAH.

  16. The total and freely dissolved polycyclic aromatic hydrocarbons content in residues from biogas production.

    PubMed

    Stefaniuk, Magdalena; Oleszczuk, Patryk

    2016-01-01

    In the situation of increasing agricultural utilization of residues from biogas production (RBP) it is important to determine the concentration of contaminants, which could occur in these materials. The group of contaminants that requires special attention are polycyclic aromatic hydrocarbons (PAH). The objective of the study was to determine the total and freely dissolved (Cfree) of PAHs in RBP from 6 different biogas plants operating under various temperature conditions and without or with the separation into the solid and liquid fractions. The freely dissolved PAHs were determined using polyoxymethylene (POM method). The total content of the Σ16 PAHs in RBP varied from 449 to 6147 μg/kgdw, while that of Cfree PAHs was at the level from 57 to 653 ng/L. No significant differences were noted in the content of the Σ16 PAHs (total) between the solid and the liquid fractions. This indicates that in the course of the separation, the PAHs are distributed proportionally between the fractions. However in the case of Cfree, PAHs content in the solid fraction was over twice as high as in the liquid fraction. This was probably due to the greater affinity of the particles present in the liquid fraction to the analysed PAHs than to the particles of the solid fraction. Higher affinity to liquid fraction was also confirmed by the distribution coefficients KTOC determined on the basis of Cfree. PMID:26586628

  17. Residual indoor contamination from world trade center rubble fires as indicated by polycyclic aromatic hydrocarbon profiles.

    PubMed

    Pleil, Joachim D; Funk, William E; Rappaport, Stephen M

    2006-02-15

    The catastrophic destruction of the World Trade Center (WTC) on Sept. 11, 2001 (9/11) created an immense dust cloud followed by fires that emitted smoke and soot into the air of New York City (NYC) well into December. Outdoor pollutant levels in lower Manhattan returned to urban background levels after about 200 days as the fires were put out and the debris cleanup was completed. However, particulate matter (PM) from the original collapse and fires also penetrated into commercial and residential buildings. This has created public concern because WTC dust is thought to cause adverse pulmonary symptoms including "WTC cough" and reduced lung capacity. Additionally, some recent studies have suggested a possible link between exposure to WTC contamination and other adverse health effects. Distinguishing between normal urban pollutant infiltration and residual WTC dust remaining in interior spaces is difficult; efforts are underway to develop such discriminator methods. Some progress has been made in identifying WTC dust by the content of fibers believed to be associated with the initial building collapse. There are also contaminants created by the fires that burned for 100 days in the debris piles of the building rubble. Using WTC ambient air samples, we have developed indicators for fire related PM based on the relative amounts of specific particle bound polycyclic aromatic hydrocarbons (PAHs) and the mass fraction of PAHs per mass of PM. These two parameters are combined, and we show a graphical method for discriminating between fire sources and urban particulate sources as applied to samples of settled dusts. We found that our PAHs based discriminator method can distinguish fire source contributions to WTC related particulate matter and dusts. Other major building fires or large open burn events could have similar PAHs characteristics. We found that random samples collected approximately 3.5 years after the WTC event from occupied indoor spaces (primarily residential

  18. Transformation of chlorinated hydrocarbons using aquocobalamin or coenzyme F{sub 430} in combination with zero-valent iron

    SciTech Connect

    Morra, M.J.; Borek, V.; Koolpe, J.

    2000-06-01

    More effective methods are necessary for the remediation of soils, sediments, and ground waters contaminated with halogenated organic compounds. The authors objective was to determine the feasibility and utility of using a tetrapyrrole-Fe(0) mixture for reductive dehalogenation of synthetic organic contaminants. Aquocobalamin or coenzyme F{sub 430} was combined with Fe(0) in aqueous systems containing either a single chlorinated compound or mixtures of chlorinated compounds, and substrate disappearance was monitored using gas chromatography-mass spectrometry (GC-MS). Zero-valent iron effectively dehalogenated CCl{sub 4} at low to neutral pH values, while increases in CCl{sub 4} dehalogenation resulting from inclusion of tetrapyrrole catalysts along with Fe(0) occurred only at basic pH values. Rates of CCl{sub 4} disappearance increased with additional aquocobalamin, but reached a maximum and decreased at higher aquocobalamin concentrations. overall dehalogenation rates may thus be a function of Fe(0)'s limited reactive surface area. There was a trend for both tetrapyrrole catalysts to promote the disappearance of halogenated compounds in a mixed substrate containing 20 compounds. Studies with five individual substrates likewise showed trends for increased substrate removal with F{sub 430} beyond that for Fe(0) alone. This increase is most important for compounds such as 1,2-dichloroethane and 1,4-dichlorobenzene that are not readily dehalogenated by Fe(0). Chloride concentrations in the reaction mixtures indicated that reductive dehalogenation was the dominant process responsible for substrate disappearance. Use of a combination of aquocobalamin or coenzyme F{sub 430} and Fe(0) may effectively promote dehalogenation, thus producing fewer products and more complete dehalogenation of the target substrates than can be achieved using only one of the abiotic reductants alone.

  19. Bugs digest chlorinated organics

    SciTech Connect

    Not Available

    1993-02-01

    This article describes a new bioreactor that uses a consortium of aerobic bacteria to biodegrade chlorinated aromatic hydrocarbons. Methanotrophic bacteria are cultivated for their MMO enzyme. After the MMO enzyme breaks down the chlorinated organics by oxidation, non-methanotrophic bacteria consume the byproducts. Pilot-scale testing has demonstrated successful treatment of groundwater containing coal-tar constituents, toluene, trichloroethylene, vinyl chlorides, chlorobenzene, and methyl methacrylate from three Superfund sites.

  20. Comparison of two extraction methods for the analysis of petroleum hydrocarbon residues in mallard duck eggs by GC and GC-MS. [NONE

    SciTech Connect

    Belisle, A.A.; Gay, M.L.; Coon, N.C.

    1981-01-01

    Hydrocarbon residues in pooled eggs from a mallard duck on a diet of 25,000 ppm South Louisiana crude oil were compared after cleanup with and without saponification. The saponification procedure yielded superior reproducibility and extraction efficiency..

  1. Comparison of two extraction methods for the analysis of petroleum hydrocarbon residues in mallard duck eggs by GC and GC-MS

    USGS Publications Warehouse

    Belisle, A.A.; Gay, M.L.; Coon, N.C.

    1981-01-01

    Hydrocarbon residues in pooled eggs from a mallard duck on a diet of 25,000 ppm South Louisiana crude oil were compared after cleanup with and without saponification. The saponification procedure yielded superior reproducibility and extraction efficiency

  2. Catalytic systems for processes of oxidative systems for processes of oxidative chlorination of hydrocarbons. Communication 4. X-ray diffraction study of formation of catalysts on various classes of supports

    SciTech Connect

    Solomonik, I.G.; Kurlyandskaya, I.I.; Ashavskaya, G.A.; Yakerson, V.I.

    1986-10-10

    It is usually assumed that the salt component in supported catalysts, which may be in the liquid phase, is physically distributed in the system of micropores and macropores of the support. Chemical interaction with various supports, differing in nature and structure, has been observed in catalysts for the oxidative chlorination of hydrocarbons. In this article the authors present results from an x-ray diffraction study of supported copper-containing salt systems. It is shown that in supported copper chloride catalysts for the oxidative chlorination of hydrocarbons, the salt component interacts with the support (metastable aluminum oxides or an amorphous aluminosilicate), this interaction leading to the formation of a complex multiphase system. The structure of the support influences the crystallization of the excess salt component, resulting in oriented growth of the crystals. On an aluminosilicate support, copper hydroxochlorides are formed selectively, so that they constitute a large part of the supported salt component.

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

    SciTech Connect

    Umezu, Toyoshi Shibata, Yasuyuki

    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.

  4. An evaluation of the use of an advanced oxidation process to remove chlorinated hydrocarbons from groundwater at the US Department of Energy Kansas City Plant

    SciTech Connect

    Garland, S.B. II; Peyton, G.R.

    1990-10-01

    The Allied-Signal Aerospace Company currently operates a production facility in Kansas City, Missouri, under contract with the US Department of Energy (DOE). Over the years the operation of the DOE Kansas City Plant has resulted in the contamination of groundwater with chlorinated hydrocarbons, including trichloroethene (TCE). One of the plumes of contaminated groundwater, the underground tank farm (UTF) plume, was selected for remediation with an advanced oxidation process (AOP) consisting of simultaneous treatment by ozone (O{sub 3}), ultraviolet (UV) radiation, and hydrogen peroxide (H{sub 2}O{sub 2}). Since the use of AOPs is relatively new for the removal of organics from groundwater, information on design criteria, costs, performance, and operating experience is not well documented in the literature. Therefore, the Oak Ridge National Laboratory (ORNL) was requested to evaluate the treatment process. This report documents the work performed through FY 1989. The results of the initial year of the evaluations, FY 1988, have been published previously, and the evaluation will continue at least through FY 1990. This report first briefly describes the treatment plant and the mechanisms of the treatment process. Next, the methodology and the results from the evaluation are discussed. Finally, conclusions and recommendations are presented. 8 refs., 14 figs., 16 tabs.

  5. Distribution of polycyclic aromatic hydrocarbons in fly ash during coal and residual char combustion in a pressurized fluidized bed

    SciTech Connect

    Hongcang Zhou; Baosheng Jin; Rui Xiao; Zhaoping Zhong; Yaji Huang

    2009-04-15

    To investigate the distribution of polycyclic aromatic hydrocarbons (PAHs) in fly ash, the combustion of coal and residual char was performed in a pressurized spouted fluidized bed. After Soxhlet extraction and Kuderna-Danish (K-D) concentration, the contents of 16 PAHs recommended by the United States Environmental Protection Agency (U.S. EPA) in coal, residual char, and fly ash were analyzed by a high-performance liquid chromatography (HPLC) coupled with fluorescence and diode array detection. The experimental results show that the combustion efficiency is lower and the carbon content in fly ash is higher during coal pressurized combustion, compared to the residual char pressurized combustion at the pressure of 0.3 MPa. Under the same pressure, the PAH amounts in fly ash produced from residual char combustion are lower than that in fly ash produced from coal combustion. The total PAHs in fly ash produced from coal and residual char combustion are dominated by three- and four-ring PAHs. The amounts of PAHs in fly ash produced from residual char combustion increase and then decrease with the increase of pressure in a fluidized bed. 21 refs., 1 fig., 4 tabs.

  6. Evaluation of solid polymeric organic materials for use in bioreactive sediment capping to stimulate the degradation of chlorinated aliphatic hydrocarbons.

    PubMed

    Atashgahi, Siavash; Maphosa, Farai; De Vrieze, Jo; Haest, Pieter Jan; Boon, Nico; Smidt, Hauke; Springael, Dirk; Dejonghe, Winnie

    2014-03-01

    In situ bioreactive capping is a promising technology for mitigation of surface water contamination by discharging polluted groundwater. Organohalide respiration (OHR) of chlorinated ethenes in bioreactive caps can be stimulated through incorporation of solid polymeric organic materials (SPOMs) that provide a sustainable electron source for organohalide respiring bacteria. In this study, wood chips, hay, straw, tree bark and shrimp waste, were assessed for their long term applicability as an electron donor for OHR of cis-dichloroethene (cDCE) and vinyl chloride (VC) in sediment microcosms. The initial release of fermentation products, such as acetate, propionate and butyrate led to the onset of extensive methane production especially in microcosms amended with shrimp waste, straw and hay, while no considerable stimulation of VC dechlorination was obtained in any of the SPOM amended microcosms. However, in the longer term, short chain fatty acids accumulation decreased as well as methanogenesis, whereas high dechlorination rates of VC and cDCE were established with concomitant increase of Dehalococcoides mccartyi and vcrA and bvcA gene numbers both in the sediment and on the SPOMs. A numeric simulation indicated that a capping layer of 40 cm with hay, straw, tree bark or shrimp waste is suffice to reduce the groundwater VC concentration below the threshold level of 5 μg/l before discharging into the Zenne River, Belgium. Of all SPOMs, the persistent colonization of tree bark by D. mccartyi combined with the lowest stimulation of methanogenesis singled out tree bark as a long-term electron donor for OHR of cDCE/VC in bioreactive caps. PMID:23955471

  7. Estimating the in situ sediment-porewater distribution of PAHs and chlorinated aromatic hydrocarbons in anthropogenic impacted sediments

    SciTech Connect

    Hans Peter H. Arp; Gijs D. Breedveld; Gerard Cornelissen

    2009-08-15

    It has become increasingly apparent that the in situ sediment-porewater distribution behavior of organic compounds within anthropogenic impacted sediments is quite diverse, and challenging to generalize. Traditional models based on octanol-water partitioning generally overestimate native porewater concentrations, and modern approaches accounting for multiple carbon fractions, including black carbon, appear sediment specific. To assess the diversity of this sorption behavior, we collected all peer-reviewed total organic carbon (TOC)-normalized in situ sediment-porewater distribution coefficients, K{sub TOC}, for impacted sediments. This entailed several hundreds of data for PAHs, PCBs, PCDD/Fs, and chlorinated benzenes, covering a large variety of sediments, locations, and experimental methods. Compound-specific KTOC could range up to over 3 orders of magnitude. Output from various predictive models for individual carbonaceous phases found in impacted sediments, based on peer-reviewed polyparameter linear free energy relationships (PP-LFERs), Raoult's Law, and the SPARC online-calculator, were tested to see if any of the models could consistently predict literature K{sub TOC} values within a factor of 30 (i.e. about 1.5 orders of magnitude, or half the range of K{sub TOC} values). The Raoult's Law model and coal tar PP-LFER achieved the sought-after accuracy for all tested compound classes, and are recommended for general, regional-scale modeling purposes. As impacted sediment-porewater distribution models are unlikely to get more accurate than this, this review underpins that the only way to accurately obtain accurate porewater concentrations is to measure them directly, and not infer them from sediment concentrations. 86 refs., 2 figs., 3 tabs.

  8. Aqueous chlorination of resorcinol

    USGS Publications Warehouse

    Heasley, V.L.; Burns, M.D.; Kemalyan, N.A.; Mckee, T.C.; Schroeter, H.; Teegarden, B.R.; Whitney, S.E.; Wershaw, R. L.

    1989-01-01

    An investigation of the aqueous chlorination (NaOCl) of resorcinol is reported. The following intermediates were detected in moderate to high yield at different pH values and varying percentages of chlorination: 2-chloro-, 4-chloro-, 2,4-dichloro-, 4,6-dichloro- and 2,4,6-trichlororesorcinol. Only trace amounts of the intermediates were detected when the chlorination was conducted in the presence of phosphate buffer. This result has significant implications since resorcinol in phosphate buffer has been used as a model compound in several recent studies on the formation of chlorinated hydrocarbons during chlorination of drinking water. Relative rates of chlorination were determined for resorcinol and several of the chlorinated resorcinols. Resorcinol was found to chlorinate only three times faster than 2,4,6-trichlororesorcinol. The structure 2,4,6-trichlororesorcinol was established as a monohydrate even after sublimation. A tetrachloro or pentachloro intermediate was not detected, suggesting that the ring-opening step of such an intermediate must be rapid. ?? 1989.

  9. Mobilization of soil bound residue of organochlorine pesticides and polycyclic aromatic hydrocarbons in an in-vitro gastrointestinal model

    PubMed Central

    TAO, SHU; LI, LI; DING, JUNNAN; ZHONG, JUNJUN; ZHANG, DIYU; LU, YAN; YANG, YIFENG; WANG, XILONG; LI, XIQING; CAO, JUN; LU, XIAOXIA; LIU, WENXIN

    2011-01-01

    A previous study on mobilization of organochlorine pesticides (OCPs) in contaminated soils from the field revealed that the total amount of OCPs measured in digestive fluid and chyme of an in-vitro gastrointestinal model was higher than the quantity directly extracted using a solvent extraction without digestion, providing a clue that the bound residue of OCPs might be mobilized. This hypothesis was tested in this study for both OCPs and polycyclic aromatic hydrocarbons (PAHs). Three contaminated surface soil samples with different organic carbon (OC) contents were collected from the field, and extracted with a solvent with and without digestion in an in-vitro gastrointestinal model. It was found that bound residues of OCPs and PAHs were mobilized to a certain extent during digestion. The ratios of the mobilized bound residues over the total quantities extracted after digestion (Rb) varied from 0 to 0.96 for individual compounds. The Rb was positively correlated with OC content. Among the five constitutes of digestive juice, bile salt was the only one that served to mobilize the bound residues and the extractability of bile salt was constant over a concentration range from 2 to 20 mg/mL. The mobilization process followed typical first-order kinetics. The calculated rate constants suggest that mobilization was fast and 90% of extracted bound residues of OCPs and PAHs were mobilized within 2.4 and 4.8 h, respectively. PMID:21175124

  10. Chlorinated hydrocarbons and biomarkers of exposure in wading birds and fish of the Lower Rio Grande Valley, Texas

    USGS Publications Warehouse

    Wainwright, S.E.; Mora, M.A.; Sericano, J.L.; Thomas, P.

    2001-01-01

    During 1997 we evaluated reproductive success in colonial water birds nesting in the Lower Rio Grande Valley (LRGV), Texas, and correlated success with concentrations of contaminants in eggs. We also measured steroid hormones and gonadosomatic index (GSI) as biomarkers of endocrine effects in common carp (Cyprinus carpio). Nest and fledging success of green herons (Butorides virescens) and great egrets (Ardea alba) were similar to those found in other parts of North America; however, nesting success of black-crowned night-herons (Nycticorax nycticorax) was lower, very likely due to flooding of the nesting area. Except for DDE and toxaphene, all chlorinated pesticides in bird eggs were low and not of concern for negative effects on any of the three species. DDE was highest in green heron eggs and seemed to increase along a geographic gradient from west to east, with eggs from Falcon Reservoir containing low concentrations, and those at Los Indios containing the highest concentrations (approx. 11,000 ng/g WW), near or above the threshold for reproductive impairment. DDE levels in great egrets and black-crowned night-herons were below those that are associated with reproductive impairment. Mean DDE levels in carp at the JAS Farms site were above the threshold level suggested for predator protection. Toxaphene was detected in about 20% of the samples with high levels observed in green heron eggs from Los Indios (mean = 4,402 ng/g WW). These are the highest toxaphene levels reported in bird eggs in the LRGV. Toxaphene levels in fish ranged between 90 and 312 ng/g WW. In general, PCBs in bird eggs and fish tissue were low and at levels not of concern for reproductive effects. The greatest concentrations of testosterone and 11-ketotestosterone were detected in fish from the JAS Farms site, which also had the greatest concentrations of DDE. Increased androgen production and gonad development in fish at this site, relative to Pharr, could be possibly associated with

  11. Tenax-GC Extraction Technique for Residual Polychlorinated Biphenyl and Polyaromatic Hydrocarbon Analysis in Biodegradation Assays

    PubMed Central

    Shiaris, M. P.; Sherrill, T. W.; Sayler, G. S.

    1980-01-01

    A rapid Tenax-GC extraction technique has been evaluated for use in conjunction with aqueous biodegradation assays for polyaromatic hydrocarbons and polychlorinated biphenyls. The method was quantitatively efficient and reproducible for phenanthrene, but variable and not quantitative for Aroclor 1254 (polychlorinated biphenyls). Aqueous sample volumes and varying concentrations of organic matter influenced polychlorinated biphenyl and polyaromatic hydrocarbon extraction efficiency. Phenanthrene recovery was decreased by soil extract but unaffected by spent bacteriological culture medium. Both types of organic matter caused significant reduction of Aroclor 1254 recovery. Polyaromatic hydrocarbon and polychlorinated biphenyl biodegradation assays, performed with reservoir samples, supported the laboratory evaluation. The study demonstrated the utility of the Tenax-GC extraction technique for phenanthrene analysis in biodegradation assessment; however, Tenax-GC extraction was not appropriate for Aroclor 1254 biodegradation studies. PMID:16345486

  12. Chlorine: state of the art.

    PubMed

    Evans, Richard B

    2005-01-01

    Chlorine is a widely used industrial chemical. Individuals can be exposed to chlorine through transportation accidents, industrial exposures or misuse of domestic cleaners. While most exposed individuals recover normal pulmonary function, chlorine can cause a variety of lung injuries including pulmonary edema, restrictive lung disease, and obstructive disease, including Reactive Airways Dysfunction Syndrome. Residual effects of chlorine exposure are a function of intensity of exposure, minute ventilation during exposure, and host characteristics such as cigarette smoking and atopy. This monograph will summarize uses of chlorine, the potential for accidents, the mechanism of chlorine toxicity in the lung, and review acute and chronic effects of chlorine exposure on the lung, as well as systemic effects of massive chlorine exposure. PMID:16078037

  13. Residues of organochlorine pesticides and polycyclic aromatic hydrocarbons in farm-raised livestock feeds and manures in Jiangsu, China.

    PubMed

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

    2013-04-15

    The residual levels of 8 organochlorine pesticides (OCPs) and 15 priority polycyclic aromatic hydrocarbons (PAHs) were determined in pig, chicken, and cow feed and manure samples collected from feedlots in Jiangsu province, China. The mean residuals of OCPs ranged from 25.35 to 65.62 ng g(-1) in feeds and from 33.46 to 90.89 ng g(-1) in manures. Among 4 hexachlorocyclohexanes (HCHs), α-HCH was the most abundant compound, with a high occurrence above 80% in all kinds of animal feeds and manures. For dichlorodiphenyltrichloroethanes (DDTs), the predominance of p,p'-DDE and p,p'-DDT of total DDTs was also clearly observed. Composite profiles of HCHs and DDTs in feeds indicated that the residuals of lindane and DDTs could be attributed to new inputs in the past several years. The mean residuals of all of the PAHs varied from 128.94 to 389.66 ng g(-1) in manures. The mean concentrations of seven carcinogenic PAHs in manures varied from 16.80 to 79.70 ng g(-1). Of the 15 priority PAHs, phenanthrene was the most dominant PAH species and accounted for approximately 50% of the total PAHs in all animal manures. The distribution of PAHs with different rings showed that PAHs with 3 rings were the primary components in the tested manures. PMID:23058310

  14. Behaviour of I/Br/Cl-THMs and their projected toxicities under simulated cooking conditions: Effects of heating, table salt and residual chlorine.

    PubMed

    Yan, Mingquan; Li, Mingyang; Han, Xuze

    2016-08-15

    This study examined the effects of heating, residual chlorine and concentration of table salt on the generation of iodine-, bromine- and chlorine-containing trihalomethanes (THMs) under simulated cooking conditions. In the case of addition of either KI- or KIO3-fortified salt, total I-THM concentrations increased with increasing iodine concentration, while total Cl/Br-THM concentrations decreased. CHCl2I, CHBrClI, CHBrI2, CHBr2I and CHI3 were formed in the presence of KI salt, while only CHCl2I was formed in the presence of KIO3 salt. CHCl2I was unstable under cooking conditions, and >90% of this DBP was removed during heating, which in some cases increased the concentrations of the other I-THMs. The calculated cytotoxicity increased with addition of KI- or KIO3-fortified salt due to the generation of I-THMs, whose impact on the cytotoxicity at room temperature was equal to or five times higher, respectively, than the cytotoxicity of the simultaneously formed Cl/Br-THMs for the cases of salts. Heating decreased the cytotoxicity, except for the case of addition of KI salt, in which the calculated cytotoxicity of I-THMs increased above 150% as the temperature was increased up to 100°C. The reported results may have important implications for epidemiologic exposure assessments and, ultimately, for public health protection. PMID:27107240

  15. RADIO FREQUENCY ENHANCED DECONTAMINATION OF SOILS CONTAMINATED WITH HALOGENATED HYDROCARBONS

    EPA Science Inventory

    There has been considerable effort in the development of innovative treatment technologies for the clean up of sites containing hazardous wastes such as hydrocarbons and chlorinated hydrocarbons. Typical examples of such waste material are: chlorinated solvents, polychlorinated b...

  16. Use of mussels and semipermeable membrane devices to assess bioavailability of residual polynuclear aromatic hydrocarbons three years after the Exxon Valdez oil spill

    SciTech Connect

    Shigenaka, G.; Henry, C.B. Jr.

    1995-12-31

    Mussels (Mytilus cf. trossulus) were transplanted to a heavily oiled and extensively treated site on Smith Island, Prince William Sound, Alaska, in 1992. A new monitoring and assessment tool, the semipermeable membrane device, was also deployed to compare hydrocarbon uptake with mussels and to evaluate the route of exposure to mussels. Both mussels and semipermeable membrane devices accumulated polynuclear aromatic hydrocarbons during 14- and 52-day deployments, particularly at the oiled site. Accumulation levels were similar between mussels and the semipermeable membrane devices, but the distribution of individual hydrocarbons differed. The results permit some inference about route of exposure to mussels. Sheens leaching from subsurface deposits of residual oil, and particulate material with adsorbed hydrocarbons were apparently more important exposure pathways than dissolved hydrocarbons in water. Semipermeable membrane devices show promise as monitoring tools and to provide insights into exposure pathways for biota. 20 refs., 7 figs., 4 tabs.

  17. Remediation of inorganic contaminants and polycyclic aromatic hydrocarbons from soils polluted by municipal solid waste incineration residues.

    PubMed

    Jobin, Philippe; Coudert, Lucie; Taillard, Vincent; Blais, Jean-Francois; Mercier, Guy

    2016-08-01

    Three soils polluted by municipal solid waste (MSW) incineration residues and containing various concentrations of Cu, Pb, Sb, Sn and Zn were treated using magnetism, gravity separation (jig and shaking table) and flotation/leaching. The process removed between 18% and 39% of the contaminants present in soil 1, between 31% and 53% of the contaminants present in soil 2 and between 42% and 56% of the contaminants present in soil 3. Polycyclic aromatic hydrocarbons were present only in soil 3, and the process removed 64% of its PAHs total content. Magnetism seemed to be the most efficient technique to remove metals from contaminated soils, followed by gravity separation and finally flotation/leaching. The global efficiency of the process was higher when the initial contaminant concentrations were lower (smaller proportions of MSW incineration residues). The estimated costs of the process, including direct and indirect costs, varied from $82 to $88 per ton of treated soil depending on the proportion of MSW incineration residues mixed with the soil. PMID:26729603

  18. Reaction products of chlorine dioxide.

    PubMed Central

    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 dioxide treatment of organic materials are oxidized species, some of which also contain chlorine. The relative amounts of species types may depend on the amount of chlorine dioxide residual maintained and the concentration and nature of the organic material present in the source water. The trend toward lower concentrations of chlorinated by-products with increasing ClO2 concentration, which was observed with phenols, has not been observed with natural humic materials as measured by the organic halogen parameter. Organic halogen concentrations have been shown to increase with increasing chlorine dioxide dose, but are much lower than those observed when chlorine is applied. Aldehydes have been detected as apparent by-products of chlorine dioxide oxidation reactions in a surface water that is a drinking water source. Some other nonchlorinated products of chlorine dioxide treatment may be quinones and epoxides. The extent of formation of these moieties within the macromolecular humic structure is also still unknown. PMID:7151750

  19. Role of Hot Water System Design on Factors Influential to Pathogen Regrowth: Temperature, Chlorine Residual, Hydrogen Evolution, and Sediment

    PubMed Central

    Brazeau, Randi H.; Edwards, Marc A.

    2013-01-01

    Abstract Residential water heating is linked to growth of pathogens in premise plumbing, which is the primary source of waterborne disease in the United States. Temperature and disinfectant residual are critical factors controlling increased concentration of pathogens, but understanding of how each factor varies in different water heater configurations is lacking. A direct comparative study of electric water heater systems was conducted to evaluate temporal variations in temperature and water quality parameters including dissolved oxygen levels, hydrogen evolution, total and soluble metal concentrations, and disinfectant decay. Recirculation tanks had much greater volumes of water at temperature ranges with potential for increased pathogen growth when set at 49°C compared with standard tank systems without recirculation. In contrast, when set at the higher end of acceptable ranges (i.e., 60°C), this relationship was reversed and recirculation systems had less volume of water at risk for pathogen growth compared with conventional systems. Recirculation tanks also tended to have much lower levels of disinfectant residual (standard systems had 40–600% higher residual), 4–6 times as much hydrogen, and 3–20 times more sediment compared with standard tanks without recirculation. On demand tankless systems had very small volumes of water at risk and relatively high levels of disinfectant residual. Recirculation systems may have distinct advantages in controlling pathogens via thermal disinfection if set at 60°C, but these systems have lower levels of disinfectant residual and greater volumes at risk if set at lower temperatures. PMID:24170969

  20. Study of weathering effects on the distribution of aromatic steroid hydrocarbons in crude oils and oil residues.

    PubMed

    Wang, Chuanyuan; Chen, Bing; Zhang, Baiyu; Guo, Ping; Zhao, Mingming

    2014-01-01

    The composition and distribution of triaromatic steroid hydrocarbons in oil residues after biodegradation and photo-oxidation processes were detected, and the diagnostic ratios for oil spill identification were developed and evaluated based on the relative standard deviation (RSD) and the repeatability limit. The preferential loss of C27 methyl triaromatic steranes (MTAS) relative to C28 MTAS and C29 MTAS was shown during the photo-oxidation process. In contrast to the photochemical degradation, the MTAS with the original 20R biological configuration was preferentially degraded during the biodegradation process. The RSD of most of the diagnostic ratios of MTAS ranged from 9 to 84% during the photo-oxidation process. However, the RSDs of such ratios derived from MTAS were all <5% even in high biodegradation, and such parameters may also provide new methods on oil spill identification. The parameters of monoaromatic sterane and monoaromatic sterane are not used well for oil spill identification after photo-oxidation. The triaromatic steroid hydrocarbons retained their molecular compositions after biodegradation and photo-oxidation and most of the diagnostic ratios derived from them could be efficiently used in oil spill identification. PMID:25144907

  1. Inactivation of influenza virus haemagglutinin by chlorine dioxide: oxidation of the conserved tryptophan 153 residue in the receptor-binding site.

    PubMed

    Ogata, Norio

    2012-12-01

    Airborne influenza virus infection of mice can be prevented by gaseous chlorine dioxide (ClO(2)). This study demonstrated that ClO(2) abolished the function of the haemagglutinin (HA) of influenza A virus (H1N1) in a concentration-, time- and temperature-dependent manner. The IC(50) during a 2 min reaction with ClO(2) at 25 °C was 13.7 µM, and the half-life time of HA with 100 µM ClO(2) at 25 °C was 19.5 s. Peptides generated from a tryptic digest of ClO(2)-treated virus were analysed by mass spectrometry. An HA fragment, (150)NLLWLTGK(157) was identified in which the tryptophan residue (W153) was 32 mass units greater than expected. The W153 residue of this peptide, which is derived from the central region of the receptor-binding site of HA, is highly conserved. It was shown that W153 was oxidized to N-formylkynurenine in ClO(2)-treated virus. It was concluded that the inactivation of influenza virus by ClO(2) is caused by oxidation of W153 in HA, thereby abolishing its receptor-binding ability. PMID:22933663

  2. Removal of polycyclic aromatic hydrocarbons from aqueous solution by raw and modified plant residue materials as biosorbents.

    PubMed

    Xi, Zemin; Chen, Baoliang

    2014-04-01

    Removal of polycyclic aromatic hydrocarbons (PAHs), e.g., naphthalene, acenaphthene, phenanthrene and pyrene, from aqueous solution by raw and modified plant residues was investigated to develop low cost biosorbents for organic pollutant abatement. Bamboo wood, pine wood, pine needles and pine bark were selected as plant residues, and acid hydrolysis was used as an easily modification method. The raw and modified biosorbents were characterized by elemental analysis, Fourier transform infrared spectroscopy and scanning electron microscopy. The sorption isotherms of PAHs to raw biosorbents were apparently linear, and were dominated by a partitioning process. In comparison, the isotherms of the hydrolyzed biosorbents displayed nonlinearity, which was controlled by partitioning and the specific interaction mechanism. The sorption kinetic curves of PAHs to the raw and modified plant residues fit well with the pseudo second-order kinetics model. The sorption rates were faster for the raw biosorbents than the corresponding hydrolyzed biosorbents, which was attributed to the latter having more condensed domains (i.e., exposed aromatic core). By the consumption of the amorphous cellulose component under acid hydrolysis, the sorption capability of the hydrolyzed biosorbents was notably enhanced, i.e., 6-18 fold for phenanthrene, 6-8 fold for naphthalene and pyrene and 5-8 fold for acenaphthene. The sorption coefficients (Kd) were negatively correlated with the polarity index [(O+N)/C], and positively correlated with the aromaticity of the biosorbents. For a given biosorbent, a positive linear correlation between logKoc and logKow for different PAHs was observed. Interestingly, the linear plots of logKoc-logKow were parallel for different biosorbents. These observations suggest that the raw and modified plant residues have great potential as biosorbents to remove PAHs from wastewater. PMID:25079403

  3. Utilizing polymer-coated vials to illustrate the fugacity and bioavailability of chlorinated pesticide residues in contaminated soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fugacity and bioavailability concepts can be challenging topics to communicate effectively in the timeframe of an academic laboratory course setting. In this experiment, students observe partitioning of the residues over time into an artificial biological matrix. The three compounds utilized are o...

  4. Gamma radiolysis of chlorinated hydrocarbons

    SciTech Connect

    Arbon, R.E.; Mincher, B.J.; Meikrantz, D.H.

    1992-08-01

    This program is the Idaho National Engineering Laboratory (INEL) component of a joint collarborative effort with Lawrence Livermore National Laboratory (LLNL). The purpose of this effort is to demonstrate a viable process for breaking down hazardous halogenated organic wastes to simpler, non-hazardous waste using high energy ionizing radiation. The INEL effort focuses on the use of spent reactor fuel gamma radiation sources to decompose complex wastes such as PCBs. At LLNL, halogenated solvents such as carbon tetrachloride and trichloroethylene are being studied using accelerator radiation sources. The INEL irradiation experiments concentrated on a single PCB congener so that a limited set of decomposition reactions could be studied. The congener 2,2{prime}, 3,3{prime},4,5{prime},6,6{prime} - octachlorobiphenyl was examined following exposure to various gamma doses at the Advanced Test Reactor (AIR) spent fuel pool. The decomposition rates and products in several solvents are discussed. 3 refs.

  5. Gamma radiolysis of chlorinated hydrocarbons

    SciTech Connect

    Arbon, R.E.; Mincher, B.J.; Meikrantz, D.H.

    1992-01-01

    This program is the Idaho National Engineering Laboratory (INEL) component of a joint collarborative effort with Lawrence Livermore National Laboratory (LLNL). The purpose of this effort is to demonstrate a viable process for breaking down hazardous halogenated organic wastes to simpler, non-hazardous waste using high energy ionizing radiation. The INEL effort focuses on the use of spent reactor fuel gamma radiation sources to decompose complex wastes such as PCBs. At LLNL, halogenated solvents such as carbon tetrachloride and trichloroethylene are being studied using accelerator radiation sources. The INEL irradiation experiments concentrated on a single PCB congener so that a limited set of decomposition reactions could be studied. The congener 2,2{prime}, 3,3{prime},4,5{prime},6,6{prime} - octachlorobiphenyl was examined following exposure to various gamma doses at the Advanced Test Reactor (AIR) spent fuel pool. The decomposition rates and products in several solvents are discussed. 3 refs.

  6. Multi-class, multi-residue analysis of pesticides, polychlorinated biphenyls, polycyclic aromatic hydrocarbons, polybrominated diphenyl ethers and novel flame retardants....mass spectrometry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  7. Black Carbon, CO2, CO, CH4, and C2-C4 Hydrocarbon Emissions from Agricultural Residue Burning

    NASA Astrophysics Data System (ADS)

    Baker, S. P.; Lincoln, E.; Richardson, M.

    2013-12-01

    The burning of agricultural crop residue represents a significant source of trace gas emissions and particulate matter on a regional and global scale. This study measured black carbon, CO, CO2, CH4 and C2 - C4 hydrocarbon emissions from the burning of agricultural grass residues. The Forest Service and Agricultural Research Service (ARS) conducted two agricultural burning experiments at ARS in Greenbelt, MD. The principal objectives were to measure spectral properties of the soil after burning, and to sample and quantify emissions. Smoke samples were collected in canisters and were analyzed by GC/FID. Emissions of black carbon were measured with an aethelometer during the burns. The first burn experiment was in May 2012. Three 10 x 10 m plots of broadcast straw with typical fuel loadings of 2, 3, and 4 T/ha were burned and sampled. The second burn experiment was in September 2012, conducted on four identical 30 x 30 m plots of grass residue, with a fuel loading of 4 T/ha. The emission factors of BC (black carbon), and GHG emissions CO2 and CH4 will be reported for both fire experiments along with other major carbon emissions. Average emission factors for the May fires were 1650 g/kg CO2 and 6.5 g/kg CH4. The September fires were of higher combustion efficiency with emission factors of 1750 g/kg for CO2 and 1.0 g/kg of CH4. BC emissions were highly positively correlated with CO concentration for all of the plots.

  8. Petroleum hydrocarbon residues in the marine environment of Bassein-Mumbai.

    PubMed

    Chouksey, Mithlesh Kumar; Kadam, A N; Zingde, M D

    2004-10-01

    The paper reports PHc contamination in water, sediment and biota of the coastal area of Bassein-Mumbai in relation to relatively less polluted sites (Dabhol and Ratnagiri) off the west coast of India. To facilitate inter-comparison three standards have been used though the results are reported in terms of SAM (Residue of Saudi Arabian Mix crude). The concentration of PHc in water off Bassein-Mumbai varies widely (2.9-39.2 microg l(-1)) as compared to the average baseline (2.8 microg l(-1)) with higher values generally confined to creeks and estuaries. The higher concentration of PHc in the bottom water of shallow areas is attributed to the contribution from the sediment-associated petroleum residue. High concentration of PHc in the surficial sediment of inshore area Ratnagiri (107.7 ppm, dry wt) is perhaps the remnants of an oil spill that occurred in the Bombay High region on May 17, 1993. The majority of values of PHc concentration in the surficial sediment of the Bassein-Mumbai region exceed 15 ppm (dry wt) against the expected background (<3 ppm, dry wt) and the trend is indicative of transfer of PHc loads from the inshore areas to the open-shore sediments. The PHc concentration of 0.8-2.6 ppm (dry wt) in sediment deposited prior to the first global commercial use of petroleum in core R5 represents the biogenic background. Based on the period of industrialisation and the horizon of PHc accumulation, a sedimentation rate of 0.2 and 1.0 cm y(-1) respectively is estimated for cores U11 and U12. Substantial increase in the concentration of PHc in sediment after 1950 in cores T8 and T10 correlates well with the establishment of refineries on the western shore of the Thane Creek in 1955-1960. A minor peak in most cores in the top 10 cm sediment probably results from biological transfer of PHc lower into the sediment by benthic organisms. Excess of PHc retained in the sediment of the Bassein-Mumbai region over the biogenic background is estimated at 40,000 t. The PHc

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

    PubMed

    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 (P<0.05) in soils and carrots but no significant correlation was found between the concentrations of any contaminants in soils and potatoes. 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

  10. Enhanced reactivity of hydroxylated polycyclic aromatic hydrocarbons to birnessite in soil: reaction kinetics and nonextractable residue formation.

    PubMed

    Jung, Jae-Woong; Lee, Seunghwan; Ryu, Hyerim; Nam, Kyoungphile; Kang, Ki-Hoon

    2008-05-01

    Phenanthrene and pyrene were not transformed by birnessite (delta-MnO2) in the presence of phenol. The phenoxy radicals generated from phenol by birnessite did not act as a mediator for polycyclic aromatic hydrocarbon radical reaction under the studied conditions. In contrast, 9-hydroxyphenanthrene and 1-hydroxypyrene were remarkably sensitive to birnessite. The disappearance patterns of the test compounds both in the aqueous phase and soil followed first-order kinetics, with a linear relationship found between the rate constants and the surface area of birnessite. Moreover, the data indicated that the reaction was faster in the presence of soil than in the aqueous phase probably because of the presence of hydroxyl groups in soil organic matter. Sequential solvent extraction was not successful in the recovery of 9-hydroxyphenanthrene from the birnessite-treated soil samples, and capillary electrophoresis data suggest the formation of nonextractable residues of the compound in soil. In addition, the acute toxicity determined by Microtox declined approximately 8.3 times in the soil samples treated with birnessite compared to untreated samples, demonstrating that the toxic compound was no longer present as its parent form. PMID:18419188

  11. Dynamics of carbon and nitrogen in a mixture of polycyclic aromatic hydrocarbons contaminated soil amended with organic residues.

    PubMed

    Rivera-Espinoza, Y; Dendooven, L

    2007-08-01

    Contamination of soil with polycyclic aromatic hydrocarbons (PAHs) through oil spills occurs frequently in Mexico. PAHs are highly resistant to degradation and restoration of these contaminated soils might be achieved by applying readily available organic material. A clayey soil was contaminated in the laboratory with different forms of PAHs, i.e. phenanthrene, anthracene and benzo(a)pyrene, and amended with maize or biosolids while production of carbon dioxide (CO2), dynamics of ammonia (NH4-), nitrate (NO3-) and PAHs were monitored. The largest CO2 production rate was found in soil added with maize and biosolids and the lowest in the unamended soil. The concentration of PAHs added to the sterilized soil did not change significantly over time and addition of organic material had no significant effect on it. The concentration of PAHs in unsterilized soil decreased sharply in the first weeks independent of addition of organic material and changes were small thereafter. After 100 days, 77% of benzo(a)pyrene was removed from soil, but 91% and 93% of phenanthrene and anthracene, respectively was removed. It was concluded that the autochthonous microbial population degraded phenanthrene, anthracene and benzo(a)pyrene, but neither biosolids nor maize accelerated the decomposition of PAHs or affected their residual concentration. PMID:17879847

  12. Studies of the movement and the formation of bound residues of atrazine, of its chlorinated derivatives, and of hydroxyatrazine in soil using /sup 14/C ring-labeled compounds under outdoor conditions

    SciTech Connect

    Schiavon, M.

    1988-02-01

    Using unperturbed-structure soil columns, placed under field conditions for a 1-year period, we have evaluated the possibilities of penetration into the soil of various /sup 14/C ring-labeled s-triazinic compounds: atrazine, chlorinated derivatives, and hydroxyatrazine. We have simultaneously examined the possibilities of formation of bound residues for each of the compounds. 2-Cl-4,6-Diaminoatrazine appears to be the product most apt to form bound residues but this reaction is paralleled by a rapid loss of total residues. On the other hand, hydroxyatrazine is a strongly adsorbed product which is lost from the soil into the atmosphere only slowly and forms practically no bound residues.

  13. Review of chlorinated phenols

    SciTech Connect

    Exon, J.H.

    1984-12-01

    The chlorinated phenols are a group of 19 isomers composed of phenol with substituted chlorines. These chemicals are readily soluble in organic solvents but only slightly soluble in water, except for the chlorophenate salts. Chlorophenols with less than 3 chlorines are not used extensively except in the production of higher chlorophenols and chlorophenyloxyacetic acid herbicides. Pentachlorophenol and some tetrachlorophenols are used worldwide, primarily as wood preservatives or fungicides. Residues of chlorophenols have been found worldwide in soil, water and air samples, in food products, and in human and animal tissues and body fluids. Environmental contamination with these chemicals occurs from industrial effluents, agricultural runoff, breakdown of chlorophenyloxyacetic acid herbicides and hexachlorobenzene, and from spontaneous formation following chlorination of water for disinfection and deodorization. The acute toxicity of these chemicals is relatively low and little is known concerning their chronic effects. Chlorophenols have not been shown conclusively to be mutagens, teratogens or carcinogens. However, these compounds may act as promotors or cocarcinogens and the immune system is particularly sensitive to their toxic effects. Transplacental exposure to chlorophenols may result in embryotoxicity and abortion. The major mode of toxic action is as uncouplers of oxidative phosphorylation. The toxicity of chlorophenols decreases with decreasing chlorination. These chemicals are mild hepatotoxins and are stored mainly in hepatic and renal tissues.

  14. Leaching of oxidic zinc materials with chlorine and chlorine hydrate

    NASA Astrophysics Data System (ADS)

    Thomas, B. K.; Fray, D. J.

    1981-06-01

    Low grade zinc ores and residues were leached in chlorine water and chlorine hydrate water mixtures. It was found that the rate of leaching Adrar ore and Electric Arc Furnace dust obeyed a shrinking core diffusion model, whereas, the rate of leaching of Turkish ore appeared to be controlled by a surface reaction. In all cases, lead leached with the zinc but the iron oxides remained virtually undissolved.

  15. Making chlorine greener: performance of alternative dechlorination agents in wastewater.

    PubMed

    MacCrehan, William A; Bedner, Mary; Helz, George R

    2005-07-01

    The residual chlorine in chlorine-disinfected and dechlorinated wastewater was characterized using a liquid chromatograph that was switched between reversed-phase separation and flow injection analysis modes, permitting measurement of fractionated and total residual chlorine, respectively. Residuals were detected in the effluent of an operating wastewater treatment plant employing chlorine disinfection and sulfite dechlorination. Despite dechlorination, an estimated total residual chlorine of 3 microM (0.2 ppm as Cl2) was detected in the effluent. To improve dechlorination effectiveness, four alternative agents (ascorbic acid, iron, sulfite plus iodide mediator, thiosulfate) were compared to sulfite on laboratory-chlorinated wastewater. Listed in order of decreasing relative effectiveness, we found: iron metal > sulfite plus iodide approximately = thiosulfate > sulfite > ascorbic acid. Only the iron metal column was completely effective at rapidly removing all traces of residual chlorine. PMID:15924957

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

    USGS Publications Warehouse

    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

  17. Analysis of organo-chlorine pesticides residue in raw coffee with a modified "quick easy cheap effective rugged and safe" extraction/clean up procedure for reducing the impact of caffeine on the gas chromatography-mass spectrometry measurement.

    PubMed

    Bresin, Bruno; Piol, Maria; Fabbro, Denis; Mancini, Maria Antonietta; Casetta, Bruno; Del Bianco, Clorinda

    2015-01-01

    The control of pesticide residues on raw coffee is a task of great importance due to high consumption of this beverage in Italy and in many other countries. High caffeine content can hamper extraction and measurement of any pesticide residue. A tandem extraction protocol has been devised by exploiting the quick easy cheap effective rugged and safe (QuEChERS) scheme for extraction, coupled to a dispersive liquid-liquid micro-extraction (DLLME) in order to drastically reduce caffeine content in the final extract. Gas chromatography-mass spectrometry (GC-MS) has been used for quantification of organo-chlorine pesticides in single ion monitoring (SIM) mode. Method has been validated and performances meet the criteria prescribed by European Union regulations. PMID:25537171

  18. Gaseous, chlorine-free chlorine dioxide for drinking water

    SciTech Connect

    Gordon, G.; Rosenblatt, A.

    1996-11-01

    The benefits of applying chlorine dioxide (ClO{sub 2}) for the oxidative treatment of drinking water are well established. Chlorine dioxide treated finished water typically has substantially lower trihalomethane (THM) levels because ClO{sub 2} will not form chlorinated organic species as a by-product of disinfection. The THMs that are formed are probably due to chlorine from the generator or chlorine used to maintain a post-disinfection residual. An emerging regulatory issue concerning the formation of disinfection by-products (DBPs) is causing the water industry to set standards for the generation and delivery of ClO{sub 2}. The Federal Register (11 February 1994) contains language developed to limit the production of the unwanted inorganic by-products chlorite (ClO{sub 2}{sup -}), chlorate (ClO{sub 3}{sup -}), and bromate (BrO{sub 3}{sup -}) ions by requiring utilities to maintain high (95%) generation efficiencies and by limiting the amount of excess Cl{sub 2} that can be used during the generation process. The efficiency and excess Cl{sub 2} regulations may be problematic for utilities that over-chlorinate to attain chlorine dioxide high yields. Many utilities will have to decide either to reduce the amount of Cl{sub 2} used to react with sodium chlorite (NaClO{sub 2}), thereby increasing the ClO{sub 2}{sup -} residual in finished water, or over-chlorinate to increase yields and surpass the excess Cl{sub 2} limits.

  19. Chlorine dioxide

    Integrated Risk Information System (IRIS)

    Chlorine dioxide ; CASRN 10049 - 04 - 4 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogeni

  20. Chlorine cyanide

    Integrated Risk Information System (IRIS)

    Chlorine cyanide ; CASRN 506 - 77 - 4 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic

  1. Estimation of polycyclic aromatic hydrocarbon concentrations in the water column based on tissue residues in mussels and salmon: An equilibrium partitioning approach

    SciTech Connect

    Neff, J.M.; Burns, W.A.

    1996-12-01

    Equilibrium partitioning was used to estimate concentrations of dissolved polycyclic aromatic hydrocarbons (PAHs) in the water column from PAH residues in tissues of mussels and juvenile pink salmon collected from coastal marine waters affected by the Exxon Valdez oil spill. Estimated concentrations were within factors of 2 to 5 for fish and 5 to 10 for mussels of average total dissolved and particulate PAHs measured in concurrent water samples. Temporal trends of estimated and measured water-column PAH concentrations were comparable. Water-column PAH concentrations estimated from residues in tissues of mussels (Mytilus trossulus) were higher than estimates based on residues in tissues of juvenile pink salmon (Oncorhynchus gorbuscha). Possible reasons for this difference include seasonal variations in mussel lipid content, differences in PAH uptake and depuration rates between fish and mussels, differences in how fish and mussels interact with particulate oil, and possible short exposure times for juvenile pink salmon. All of these factors may play a role. In any event, estimates of dissolved PAHs in the water column, based on PAH residues in either fish or mussel tissue, confirm that PAH concentrations generally did not exceed water quality standards for protection of marine life.

  2. PRACTICAL APPLICATIONS OF CHLORINE DIOXIDE/FIELD DATA

    EPA Science Inventory

    Chlorine dioxide is an effective drinking water disinfectant. he major by-products of chlorine dioxide that are a concern, at this time are chlorite and chlorate. herefore, residual concentrations of these by-products should be kept as low as possible by efficient chlorine dioxid...

  3. Development of a solid-phase microextraction-based method for sampling of persistent chlorinated hydrocarbons in an urbanized coastal environment.

    PubMed

    Zeng, Eddy Y; Tsukada, David; Diehl, Dario W

    2004-11-01

    Solid-phase microextraction (SPME) has been used as an in situ sampling technique for a wide range of volatile organic chemicals, but SPME field sampling of nonvolatile organic pollutants has not been reported. This paper describes the development of an SPME-based sampling method employing a poly(dimethylsiloxane) (PDMS)-coated (100-microm thickness) fiber as the sorbent phase. The laboratory-calibrated PDMS-coated fibers were used to construct SPME samplers, and field tests were conducted at three coastal locations off southern California to determine the equilibrium sampling time and compare the efficacy of the SPME samplers with that of an Infiltrex 100 water pumping system (Axys Environmental Systems Ltd., Sidney, British Columbia, Canada). p,p'-DDE and o,p'-DDE were the components consistently detected in the SPME samples among 42 polychlorinated biphenyl congeners and 17 chlorinated pesticidestargeted. SPME samplers deployed attwo locations with moderate and high levels of contamination for 18 and 30 d, respectively, attained statistically identical concentrations of p,p'-DDE and o,p'-DDE. In addition, SPME samplers deployed for 23 and 43 d, respectively, at a location of low contamination also contained statistically identical concentrations of p,p'-DDE. These results indicate that equilibrium could be reached within 18 to 23 d. The concentrations of p,p'-DDE, o,p'-DDE, or p,p'-DDD obtained with the SPME samplers and the Infiltrex 100 system were virtually identical. In particular, two water column concentration profiles of p,p'-DDE and o,p'-DDE acquired by the SPME samplers at a highly contaminated site on the Palos Verdes Shelf overlapped with the profiles obtained by the Infiltrex 100 system in 1997. The field tests not only reveal the advantages of the SPME samplers compared to the Infiltrex 100 system and other integrative passive devices but also indicate the need to improve the sensitivity of the SPME-based sampling technique. PMID:15575294

  4. Fate of free chlorine in drinking water during distribution in premise plumbing.

    PubMed

    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

  5. Analyses of human milk samples collected in Hawaii for residues of organochlorine pesticides and polychlorobiphenyls

    SciTech Connect

    Takei, G.H.; Kauahikaua, S.M.; Leong, G.H.

    1983-01-01

    This work has revealed that the chlorinated hydrocarbon residues found in human milk samples collected from residents in the State of Hawaii were statistically the same residues found in mainland human milk samples. Moreover, the levels at which these residues were detected in Hawaiian samples were comparable to those detected in mainland samples, and differences between the two groups of samples were not apparent. The close correlation between residue analyses was unexpected considering Hawaii's geographic isolation and the distinct ethnic diets of its populations. They do indicate, however, that the uptake of chlorinated hdyrocarbon contaminants by the population of this state is not specific and is most likely due to some physiological means of entry which is common to the populations of the mainland states.

  6. 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)

    USGS Publications Warehouse

    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.

  7. U. S. EPA’S APPROACH FOR CHLORINATED SOLVENTS

    EPA Science Inventory

    The approach for chlorinated solvents is similar to the approach for petroleum hydrocarbons. However, there are more mechanisms of removal, including reductive dechlorination (biotic or abiotic), dehydrochloroelimination (abiotic), and hydrolysis (biotic or abiotic). As a resul...

  8. Chlorine Clues

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This plot shows that levels of the element chlorine rise dramatically in the deeper rocks lining the walls of the crater dubbed 'Endurance.' The data shown here were taken by the Mars Exploration Rover Opportunity's alpha particle X-ray spectrometer at Endurance and 'Eagle Crater,' the site where Opportunity first landed at Meridiani Planum.

    Opportunity has been inching down the walls of Endurance Crater, investigating distinct layers of rock as it goes for clues to Mars' buried past. The various Endurance layers have been informally labeled 'A' through 'F.' Targets within these layers are listed on the graph along with previous targets from Eagle Crater. All the rocks listed here were observed after they had been drilled by the rover's rock abrasion tool.

    The observations indicate that the elements making up the shallow rock layers of Endurance Crater resemble those of Eagle, while the deeper layers of Endurance possess increasingly higher concentrations of the element chlorine.

    Opportunity will continue to roll deeper into Endurance to see if this puzzling trend continues. Scientists hope the new data will help them figure out how the presence of chlorine fits into the history of water at Endurance Crater.

  9. River sediment (S-37)--a new analytical quality control material ensuring comparability of chlorinated hydrocarbon analysis during an international environmental study in China.

    PubMed

    Gawlik, B M; Martens, D; Henkelmann, B; Schramm, K W; Kettrup, A; Muntau, H

    2000-06-01

    A sediment reference material (S-37) was prepared as analytical quality control material to be used within an international project on polychlorinated hydrocarbon analysis in two Chinese rivers. The raw material was sampled during a cruise on Yangtse River and transported afterwards to the JRC Ispra for further processing. The material was treated according to the general principles applicable for candidate reference material production. After a thorough homogeneity study of the bulk the material was bottled. A total of 1,080 bottles each containing 50 g of dry sediment powder was obtained. Final homogeneity and stability testing proved the material to be fit for the purpose. Isotope dilution GC/MS was used to establish target values for pentachlorobenzene (1.17 +/- 0.08 ng/g), hexachlorobenzene (3.60 +/- 0.17 ng/g), octachlorostyrene (0.19 +/- 0.01 ng/g), pentachloroanisole (0.52 +/- 0.02 ng/g), alpha-HCH (0.70 +/- 0.05 ng/g), beta-HCH (1.38 +/- 0.18 ng/g), gamma-HCH (0.83 +/- 038 ng/g), 2,4'-DDT (0.36 +/- 0.04 ng/g), 2,4'-DDE (0.29 +/- 0.02 ng/g), 2,4'-DDD (0.49 +/- 0.02), 4,4'-DDT (3.42 +/- 0.47 ng/g), 4,4'-DDD (1.29 +/- 0.17 ng/g), PCB 28 (0.11 +/- 0.01 ng/g), PCB 52 (0.09 +/- 0.003 ng/g), PCB 101 (0.07 +/- 0.003 ng/g), PCB 138 (0.06 +/- 0.003 ng/g) and PCB 153 (0.06 +/- 0.003 ng/g). Furthermore, indicative values for major and minor constituents as well as for polychlorinated dibenzodioxines and -furanes were measured. PMID:11227450

  10. ELECTROCHEMICAL DEGRADATION OF CHLORINATED CONTAMINANTS IN SEDIMENTS AND GROUNDWATER

    EPA Science Inventory

    Chlorinated aliphatic and aromatic compounds account for much of the contamination found at sediments sites. Chlorinated aliphatic hydrocarbons such as trichloroethylene (TCE) occur as serious contaminants at 358 major hazardous waste sites in the USA. TCE is widely used as a sol...

  11. Stability and effectiveness of chlorine disinfectants in water distribution systems

    SciTech Connect

    Olivieri, V.P.; Snead, M.C.; Kruse, C.W.; Kawata, K.

    1986-11-01

    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 pipe were added for circulation. The levels of residual disinfectants tested were 0.2 mg/L and 1.0 mg/L as available chlorine. In the absence of a disinfectant residual, microorganisms in the sewage contaminant were consistently recovered at high levels. The presence of any disinfectant residual reduced the microorganism level and frequency of occurrence at the consumer's tap. Free chlorine was the most effective residual disinfectant and may serve as a marker or flag in the distribution network. Free chlorine and chlorine dioxide were the least stable in the pipe network. The loss of disinfectant in the pipe network followed first-order kinetics. The half-life determined in static tests for free chlorine, chlorine dioxide, and combined chlorine was 140, 93, and 1680 min.

  12. Stability and effectiveness of chlorine disinfectants in water distribution systems.

    PubMed Central

    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 pipe were added for circulation. The levels of residual disinfectants tested were 0.2 mg/L and 1.0 mg/L as available chlorine. In the absence of a disinfectant residual, microorganisms in the sewage contaminant were consistently recovered at high levels. The presence of any disinfectant residual reduced the microorganism level and frequency of occurrence at the consumer's tap. Free chlorine was the most effective residual disinfectant and may serve as a marker or flag in the distribution network. Free chlorine and chlorine dioxide were the least stable in the pipe network. The loss of disinfectant in the pipe network followed first-order kinetics. The half-life determined in static tests for free chlorine, chlorine dioxide, and combined chlorine was 140, 93, and 1680 min. PMID:3028767

  13. TREATMENT OF HYDROCARBON, ORGANIC RESIDUE AND PRODUCTION CHEMICAL DAMAGE MECHANISMS THROUGH THE APPLICATION OF CARBON DIOXIDE IN NATURAL GAS STORAGE WELLS

    SciTech Connect

    Lawrence J. Pekot; Ron Himes

    2004-05-31

    Core specimens and several material samples were collected from two natural gas storage reservoirs. Laboratory studies were performed to characterize the samples that were believed to be representative of a reservoir damage mechanism previously identified as arising from the presence of hydrocarbons, organic residues or production chemicals. A series of laboratory experiments were performed to identify the sample materials, use these materials to damage the flow capacity of the core specimens and then attempt to remove or reduce the induced damage using either carbon dioxide or a mixture of carbon dioxide and other chemicals. Results of the experiments showed that pure carbon dioxide was effective in restoring flow capacity to the core specimens in several different settings. However, in settings involving asphaltines as the damage mechanism, both pure carbon dioxide and mixtures of carbon dioxide and other chemicals provided little effectiveness in damage removal.

  14. TREATMENT OF HYDROCARBON, ORGANIC RESIDUE AND PRODUCTION CHEMICAL DAMAGE MECHANISMS THROUGH THE APPLICATION OF CARBON DIOXIDE IN NATURAL GAS STORAGE WELLS

    SciTech Connect

    Lawrence J. Pekot

    2004-06-30

    Two gas storage fields were studied for this project. Overisel field, operated by Consumer's Energy, is located near the town of Holland, Michigan. Huntsman Storage Unit, operated by Kinder Morgan, is located in Cheyenne County, Nebraska near the town of Sidney. Wells in both fields experienced declining performance over several years of their annual injection/production cycle. In both fields, the presence of hydrocarbons, organic materials or production chemicals was suspected as the cause of progressive formation damage leading to the performance decline. Core specimens and several material samples were collected from these two natural gas storage reservoirs. Laboratory studies were performed to characterize the samples that were believed to be representative of a reservoir damage mechanism previously identified as arising from the presence of hydrocarbons, organic residues or production chemicals. A series of laboratory experiments were performed to identify the sample materials, use these materials to damage the flow capacity of the core specimens and then attempt to remove or reduce the induced damage using either carbon dioxide or a mixture of carbon dioxide and other chemicals. Results of the experiments showed that pure carbon dioxide was effective in restoring flow capacity to the core specimens in several different settings. However, in settings involving asphaltines as the damage mechanism, both pure carbon dioxide and mixtures of carbon dioxide and other chemicals provided little effectiveness in damage removal.

  15. Chlorine Analysis - Water. Training Module 5.260.2.77.

    ERIC Educational Resources Information Center

    Kirkwood Community Coll., Cedar Rapids, IA.

    This document is an instructional module package prepared in objective form for use by an instructor familiar with the procedures for chlorine residual analysis. It includes objectives, an instructor guide, and student handouts. The module addresses the determination of combined and free residual chlorine in water supply samples using three…

  16. Toxicity of chlorinated insecticides to quail and pheasants

    USGS Publications Warehouse

    DeWitt, J.B.

    1956-01-01

    'Residues from insecticidal applications of chlorinated hydrocarbons may remain toxic for extended periods. In experiments designed to furnish information on the effects upon quail and pheasants of prolonged feeding upon diets containing small percentages of these compounds, it was shown that aldrin, dieldrin and endrin are cumulative, and that quail are unable to survive after ingesting 5-10 mg./kg, of aldrin, 30-50 mg./kg, of dieldrin, or 6-15 mg./kg, of endrin. Maximum levels (p.p.m.) in the diets permitting survival for extended periods were: DDT, 200; strobane, above 500; aldrin, 0.5; dieldrin, 1.0; endrin, 1.0. Inclusion of these compounds in the diets of breeding quail and pheasants affected hatchability of eggs and viability of chicks, even though the adult birds appeared unaffected.' Detailed figures are given for all points mentioned.

  17. Short-chain chlorinated paraffins in marine organisms from the Pearl River Estuary in South China: Residue levels and interspecies differences.

    PubMed

    Sun, Runxia; Luo, Xiaojun; Tang, Bin; Li, Zongrui; Huang, Liqian; Wang, Tao; Mai, Bixian

    2016-05-15

    There is limited information available on the bioaccumulation of short-chain chlorinated paraffins (SCCPs), a complicated group of persistent organic pollutants (POPs) candidates listed in the Stockholm Convention, in estuarine ecosystem. This study analyzed SCCPs in marine organisms (five fish and six invertebrates) from the Pearl River Estuary in South China. The concentrations of total SCCPs ranged from 210 to 21,000 ng · g(-1) lipid weight, with relatively higher levels in benthic invertebrates (shrimp, crabs and bivalves) than in non-benthic species (pelagic and mesopelagic fish and squid). SCCPs were biomagnified from prey fish (tapertail anchovy, Coilia mystus) to predator fish (Bombay duck, Harpadon nehereus), and the biomagnification factors (BMFs) of SCCP congeners ranged from 1.1 (C10H16Cl6) to 3.4 (C13H18Cl10). Species-specific homologue group patterns were also observed, with significantly lower proportions of C10 congeners in the shrimp, bivalves and Bombay duck than in the other species. PMID:26925731

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

    SciTech Connect

    Garrett, W.E. Jr.

    1995-06-01

    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.

  19. The residual dynamic of polycyclic aromatic hydrocarbons and organochlorine pesticides in fishponds of the Pearl River delta, South China.

    PubMed

    Kong, K Y; Cheung, K C; Wong, C K C; Wong, M H

    2005-05-01

    Hong Kong and South China are the most developed regions within China. The industrialization in these areas has resulted in severe environmental problems. Sediment and biotic samples including tilapia (Oreochromis mossambicus), bighead carp (Aristichthys nobilis), grass carp (Ctenopharyngodon idellus), crucian carp (Carassius auratus) and mandarin fish/fresh water grouper (Siniperca chuatsi) were collected from different fishponds in the Pearl River Delta (Tanzhou, Sanjiao, Guangzhou, Shipai, Changan and Mai Po) for the analysis of polycyclic aromatic hydrocarbons (PAHs) and organochlorine (OC) pesticides. Mandarin fish, which belongs to the highest trophic level, accumulated the highest concentrations of PAHs and DDTs among all fish species. The levels of DDTs in fish samples ranged from 1.5 to 62ng g-1 (wet wt.), with more than 30% of the fish samples exceeding the limit of 14.4ng g-1 (wet wt.) for human consumption recommended by US EPA (2000). Levels of PAHs in fish samples ranged from 1.91 to 224.03ng g-1 (wet wt.), but the potency-weighted total concentrations of PAHs in all muscle tissues were below the guideline value of 0.67ng g-1 (wet wt.) for human consumption set by US EPA (2000). The guideline value calculated was based on a tissue consumption rate of 142.2g day-1 (4-5 meals per week), which is a more protective rate for populations with a high consumption of fish, like Chinese and Asians. The effect of lipid content in PAHs and DDTs accumulation in fish tissue was not significant in general. PMID:15899281

  20. [Residues and risk assessment of polycyclic aromatic hydrocarbons in the surface sediments and marine organisms from Dapeng Bay, Shenzhen].

    PubMed

    Sun, Run-Xia; Ke, Chang-Liang; Gu, Yang-Guang; Lu, Teng-Teng; Du, Fei-Yan; Ma, Sheng-Wei; Lin, Qin

    2013-10-01

    In order to assess contamination by polycyclic aromatic hydrocarbons (PAHs), surface sediments and marine organism samples of fish, shrimp and shellfish were collected from the Dapeng Bay, Shenzhen in October 2011. Concentrations fof sixteen priority PAHs were determined by gas chromatography and mass spectrometry (GC-MS). The total concentrations of PAHs (Sigma PAHs ) ranged from 216. 56 ng.g-1 to 1 314. 92 ng.g-1 dry weight in sediment samples and from 70. 88 ng.g-1 to 251.90 ng.g-1 wet weight in biological samples, respectively. The mean concentration was the highest in fish (171.52 ng.g-1 ), followed by mussel (134.75 ng.g-1) and shrimp (123.35 ng.g-1) in the studied marine organisms. Compared with those in other water bodies around the world, PAHs pollution in the studied area was at medium level. The dominant fraction in the surface sediments was the 4-ring PAHs. Identification of PAH sources suggested that PAHs in Dapeng Bay were likely originated from both pyrolytic and petrogenic sources. The most abundant PAHs were 3-ring PAHs in the tissues of organisms, which may be governed by their feeding behaviors, habitats, and bioavailability of PAHs. Ecological risk assessment indicated that PAHs in surface sediments might have adverse impacts on local ecosystem. Health risk analysis revealed that the potency equivalent concentrations of BaP to the total PAHs in marine organisms from Dapeng Bay were relatively high and may cause some concerns on human health by consumption. PMID:24364300

  1. ENZYME-BASED DETECTION OF CHLORINATED HYDROCARBONS

    EPA Science Inventory

    Recent advances in immobilized enzyme-based analytical methods, e.g., the cholinesterase-based water monitor 'CAM' (cholinesterase antagonsist monitor), have proved useful in the detection of organophosphate and carbamate pesticides. This work has now been extended to the detecti...

  2. Spatial distribution of polycyclic aromatic hydrocarbons in soil, sediment, and combusted residue at an e-waste processing site in southeast China.

    PubMed

    Leung, Anna O W; Cheung, Kwai Chung; Wong, Ming Hung

    2015-06-01

    The environmental pollution and health impacts caused by the primitive and crude recycling of e-waste have become urgent global issues. Guiyu, China is a major hotspot of e-waste recycling. In this study, the levels and distribution of polycyclic aromatic hydrocarbons in soil in Guiyu were determined to investigate the effect of e-waste activities on the environment and to identify possible sources of these pollutants. Sediment samples from a local duck pond, water gullies, a river tributary, and combusted residue from e-waste burning sites were also investigated. The general trend found in soil (Σ16 PAHs) was acid leaching site > duck pond > rice field > printer roller dump site > reservoir (control site) and ranged from 95.2 ± 54.2 to 5,210 ± 89.6 ng/g (dry wt). The highest average total PAH concentrations were found in combusted residues of wires, cables, and other computer electrical components located at two e-waste open burning sites (18,600 and 10,800 ± 3,940 ng/g). These were 195- and 113-fold higher than the PAH concentrations of soil at the control site. Sediment PAH concentrations ranged from 37.2 ± 6 to 534 ± 271 ng/g. Results of this study provide further evidence of significant input of PAHs to the environment attributed to crude e-waste recycling. PMID:23338991

  3. Distribution of polycyclic aromatic hydrocarbon (PAH) residues in several tissues of edible fishes from the largest freshwater lake in China, Poyang Lake, and associated human health risk assessment.

    PubMed

    Zhao, Zhonghua; Zhang, Lu; Cai, Yongjiu; Chen, Yuwei

    2014-06-01

    The residual levels, tissue distribution and human health risk assessment of polycyclic aromatic hydrocarbons (PAHs) in edible fishes, bighead carp (Aristichthys nobilis) and silver carp (Hypophthalmichthys molitrix), from the largest freshwater lake in China, Poyang Lake, were studied. PAH concentrations ranged from 105 to 513ng g(-1)ww and from 53.9 to 401ng g(-1)ww in different tissues of bighead carp and silver carp, respectively. Low molecular weight (LMW) PAHs were the predominant compounds, suggesting the gill-water transfer might be the major exposure route for PAHs in the studied fish species. Tissue distribution indicated that the hepatobiliary system accumulated higher concentrations of PAHs than the extrahepatic tissues with bile being the most predominant tissue for both species. Composition analysis demonstrated that PAHs were from the combined petrogenic and pyrogenic origin, and the gasoline combustion might be the main source. A preliminary evaluation of human health risk using benzo[a]pyrene (BaP) potency equivalent concentration (PEC) as well as the incremental lifetime cancer risk (ILCR) indicated that PAHs in fish would induce potential carcinogenic effects. PMID:24732028

  4. Organochlorine residues in two Norwegian puffin (Fratercula arctica) colonies.

    PubMed

    Ingebrigtsen, K; Skaare, J U; Teigen, S W

    1984-01-01

    Residue levels of the chlorinated hydrocarbons hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs), alpha-, beta-, and gamma-hexachlorocyclohexane (HCH), oxychlordane, trans-nonachlor, aldrin, and dieldrin in adult puffins (Fratercula arctica) from two colonies in Norway (Røst 67 degrees 30'N and Hornøy 70 degrees 20'N) showing differences in breeding performance were compared in 1982. Furthermore, residue levels in puffin chicks from Røst in 1982, when breeding failed totally, were compared with the corresponding levels in 1983, when breeding was successful. Residue levels of chlorinated hydrocarbons were also measured in eggs from Røst 1982. An autoradiographic study of the distribution of [14C]HCB in adult puffins and chicks from Røst 1982 was included. In general, organochlorine contamination was low, and the results are interpreted to eliminate the organochlorines as a serious factor for impaired reproduction in the Røst colony. Significant differences between the two colonies are discussed in relation to geographical and nutritional aspects. The finding of significantly higher levels of organochlorines in organ tissue from puffin chicks from Røst in 1982 compared to the corresponding levels in 1983 may reflect the dramatic difference in nutritional status between the two years. PMID:6084067

  5. Hydrocarbon pneumonia

    MedlinePlus

    Pneumonia - hydrocarbon ... Coughing Fever Shortness of breath Smell of a hydrocarbon product on the breath Stupor (decreased level of ... Most children who drink or inhale hydrocarbon products and develop ... hydrocarbons may lead to rapid respiratory failure and death.

  6. The Galeta Oil Spill. III. Chronic Reoiling, Long-term Toxicity of Hydrocarbon Residues and Effects on Epibiota in the Mangrove Fringe

    NASA Astrophysics Data System (ADS)

    Levings, Sally C.; Garrity, Stephen D.; Burns, Kathryn A.

    1994-04-01

    In April 1986, 75 000-100 000 barrels of medium-weight crude oil (˜ 10 000-13 500 metric tons) spilled into Bahı´a las Minas, a large mangrove-lined bay on the Caribbean coast of Panamá. Between 1986 and 1991, biological and chemical effects of this spill were studied. The epibiota of fringing mangroves ( Rhizophora mangle L.) were examined in three habitats: (1) the shoreward margins of reef flats that fronted the open sea, (2) the edges of channels and lagoons, and (3) the banks of streams and man-made cuts that drained interior mangroves or uplands into lagoons. Chemical analyses of bivalves collected from submerged prop roots (oysters and false mussels) and records of slicks and tarry deposits on artificial roots documented chronic reoiling. Each habitat was repeatedly oiled between 1986 and 1991, with petroleum residues identified as the oil spilled in 1986. There was a decline in the release of tarry oils recorded as slicks and on roots over time, but not in tissue burdens of hydrocarbons in bivalves. This suggested that the processes that released these different types of oil residues were at least partially independent and that toxic hydrocarbons were likely to be released from sediments over the long term. The submerged prop roots of fringing mangroves in each habitat had a characteristic epibiota. On the open coast, roots were covered with a diverse assemblage of sessile invertebrates and algae. In channels, the most abundant species on roots was the edible oyster Crassostrea virginica ( rhizophorae morph). In streams, the false mussel Mytilopsis sallei covered the most space on roots. Cover of sessile invertebrates was significantly reduced at oiled compared with unoiled sites on the open coast for 4 years after oiling, while oysters and false mussels were reduced in cover at oiled sites in channels and streams through at least 1991, when observations ended. False mussels transplanted from an unoiled stream to oiled and unoiled streams were

  7. The Chlorination Quandary

    ERIC Educational Resources Information Center

    Josephson, Julian

    1978-01-01

    Current use of chlorination technology to disinfect water supplies can cause the production of undesirable products, among them chloroform and chlorobenzene. Alternatives to this methodology include the use of ozone, chlorine dioxide, and bromine chloride in place of chlorine. Presently, the methods are feasible in developed countries only. (MA)

  8. REVIEW OF CHLORINATED PHENOLS

    EPA Science Inventory

    The chlorinated phenols are a group of 19 isomers composed of phenol with substituted chlorines. These chemicals are readily soluble in organic solvents but only slightly soluble in water, except for the chlorophenate salts. Chlorophenols with less than 3 chlorines are not used e...

  9. Bioavailability of polycyclic aromatic hydrocarbons from buried shoreline oil residues thirteen years after the Exxon Valdez oil spill: a multispecies assessment.

    PubMed

    Neff, Jerry M; Bence, A Edward; Parker, Keith R; Page, David S; Brown, John S; Boehm, Paul D

    2006-04-01

    Seven taxa of intertidal plants and animals were sampled at 17 shoreline sites in Prince William Sound ([PWS]; AK, USA), that were heavily oiled in 1989 by the Exxon Valdez oil spill (EVOS) to determine if polycyclic aromatic hydrocarbons (PAH) from buried oil in intertidal sediments are sufficiently bioavailable to intertidal prey organisms that they might pose a health risk to populations of birds and wildlife that forage on the shore. Buried residues of EVOS oil are present in upper and middle intertidal sediments at 16 sites. Lower intertidal (0 m) sediments contain little oil. Much of the PAH in lower intertidal sediments are from combustion sources. Mean tissue total PAH (TPAH) concentrations in intertidal clams, mussels, and worms from oiled sites range from 24 to 36 ng/g (parts per billion) dry weight; sea lettuce, whelks, hermit crabs, and intertidal fish contain lower concentrations. Concentrations of TPAH are similar or slightly lower in biota from unoiled reference sites. The low EVOS PAH concentrations detected in intertidal biota at oiled shoreline sites indicate that the PAH from EVOS oil buried in intertidal sediments at these sites have a low bioavailability to intertidal plants and animals. Individual sea otters or shorebirds that consumed a diet of intertidal clams and mussels exclusively from the 17 oiled shores in 2002 were at low risk of significant health problems. The low concentrations of EVOS PAH found in some intertidal organisms at some oiled shoreline sites in PWS do not represent a health risk to populations of marine birds and mammals that forage in the intertidal zone. PMID:16629134

  10. ALTERNATIVES TO CHLORINATION FOR CONTROL OF CONDENSER TUBE BIO-FOULING

    EPA Science Inventory

    The report gives results of a study of methods used to reduce free-chlorine residuals in power plant effluents. Most U.S. power plants use chlorine (28,600 tons in 1972) to control biological fouling in their cooling systems, particularly in their condenser tubes. Using chlorine ...

  11. Precision Cleaning Verification of Nonvolatile Residues by Using Water, Ultrasonics, and Turbidity Analyses

    NASA Technical Reports Server (NTRS)

    Skinner, S. Ballou

    1991-01-01

    Chlorofluorocarbons (CFC's) in the atmosphere are believed to present a major environmental problem because they are able to interact with and deplete the ozone layer. NASA has been mandated to replace chlorinated solvents in precision cleaning, cleanliness verification, and degreasing of aerospace fluid systems hardware and ground support equipment. KSC has a CFC phase-out plan which provides for the elimination of over 90 percent of the CFC and halon use by 1995. The Materials Science Laboratory and KSC is evaluating four analytical methods for the determination of nonvolatile residues removal by water: (1) infrared analyses using an attenuated total reflectance; (2) surface tension analyses, (3) total organic content analyses, and (4) turbidity analyses. This research project examined the ultrasonic-turbidity responses for 22 hydrocarbons in an effect to determine: (1) if ultrasonics in heated water (70 C) will clean hydrocarbons (oils, greases, gels, and fluids) from aerospace hardware; (2) if the cleaning process by ultrasonics will simultaneously emulsify the removed hydrocarbons in the water; and (3) if a turbidimeter can be used successfully as an analytical instrument for quantifying the removal of hydrocarbons. Sixteen of the 22 hydrocarbons tested showed that ultrasonics would remove it at least 90 percent of the contaminated hydrocarbon from the hardware in 10 minutes or less giving a good ultrasonic-turbidity response. Six hydrocarbons had a lower percentage removal, a slower removal rate, and a marginal ultrasonic-turbidity response.

  12. Effects of chlorine on freshwater fish under various time and chemical conditions: toxicity of chlorine to freshwater fish. Final report

    SciTech Connect

    Brooks, A.S.; Bartos, J.M.; Danos, P.T.

    1982-07-01

    Laboratory bioassays to determine the acute toxicity of monochloramine, dichloramine, hypochlorous acid, and hypochlorite ion to emerald shiners, channel catfish, and rainbow trout were conducted. Four exposure regimes typical of chlorination schedules at operating steam electric power plants were used. Fish were exposed to single 15-minute, 30-minute, 120-minute, and quadruple 30-minute periods. No mortality or LC50 values were determined for each species of fish and chemical species of chlorine. Hypochlorous acid was the most toxic form of chlorine studied, followed closely by dichloramine. Monochloramine and hypochlorite ion were three to four times less toxic than hypochlorous acid and dichloramine. On the average, emerald shiners were 1.8 times more sensitive to chlorine than channel catfish and 3.3 times more sensitive than rainbow trout to the four forms of chlorine. The fish were more tolerant of chlorine during short duration exposures and most sensitive during the continuous 120-minute exposures. The significant differences in toxicity noted among the various chlorine species suggest that careful attention should be paid not only to total residual chlorine but to both the chlorine and fish species present and the duration of exposure expected in establishing chlorination regimes.

  13. Survival of poliovirus within organic solids during chlorination.

    PubMed Central

    Hejkal, T W; Wellings, F M; LaRock, P A; Lewis, A L

    1979-01-01

    Poliovirus in fecal homogenates was used to determine the protection against inactivation by chlorination afforded virus that was occluded within particulates. Virus that was closely associated with or occluded within small fecal particulates was protected. A fourfold increase in combined residual chlorine was required to achieve the same degree of inactivation for occluded virus as for free or secondarily adsorbed virus. A combined chlorine residual of 6.6 mg/liter was necessary to achieve 50% inactivation in 15 min at pH 8.0 and 22 degrees C in a particulate suspension containing occluded virus compared to 1.4 mg/liter for free virus. These differences were found to be relatively small compared to differences due to the presence of dissolved organics or between free and combined chlorine residuals. The results suggest different mechanisms of protection due to adsorption and occlusion. PMID:225993

  14. Atomic scale insights on chlorinated gamma-alumina surfaces.

    PubMed

    Digne, Mathieu; Raybaud, Pascal; Sautet, Philippe; Guillaume, Denis; Toulhoat, Hervé

    2008-08-20

    The thermochemistry of chlorinated gamma-alumina surfaces is explored by means of density functional calculations as a function of relevant reaction conditions used in experiments and in high-octane fuel production in the refining industry such as hydrocarbon isomerization and reforming. The role of chlorine as a dope of the Brønsted acidity of gamma-alumina surfaces is investigated at an atomic scale. Combining infrared spectroscopy and density functional theory calculations, the most favorable location of chlorine atoms on the (110), (100) and (111) surfaces of gamma-alumina is found to result either from direct adsorption or from the exchange of basic hydroxyl groups. Moreover, the modification of the hydrogen bond network upon chlorine adsorption is put forward as a key parameter for changing the Brønsted acidity. In a second step, we use a thermodynamic approach based on DFT total energy calculations corrected by the chemical potentials of HCl and H2O to determine the adsorption isotherms of chlorine and the relative surface concentration of hydroxyl groups and chlorine species on the gamma-alumina surfaces. The determination of chlorine content as a function of temperature and partial pressures of H2O and HCl offers new quantitative data required for optimizing the state of the support surface in industrial conditions. The mechanisms of chlorination are also discussed as a function of reaction conditions. PMID:18646849

  15. Development of compound-specific isotope analysis of stable chlorine in sub-µmol quantities of chlorinated organic substances

    NASA Astrophysics Data System (ADS)

    Holmstrand, H.; Andersson, P.; Gustafsson, O.

    2003-04-01

    Chlorinated hydrocarbons is a common class of substances known to be of high ecotoxicity largely due to their persistence and strongly lipophilic properties. This group of chemicals include the semivolatile compounds dichloro-diphenyl-trichloroethane (DDT) and polychlorinated biphenyls (PCB), which, together with solvents like trichloroethylene (TCE) and perchloroethylene (PCE), are globally present at detectable levels in all natural environments. Recent reports on the possibility of enzymatic synthesis of chlorinated dioxins and furans, illustrate the need for means to distinguish the naturally produced contribution from anthropogenic input to the environment. Shifts in the chlorine isotope composition due to degradation, or synthesis, of a compound are in the order of a few per mil of the initial isotope ratio. The cause of the kinetic isotope effect (KIE) arises from differences in preferential phase distribution of isotopic species. Compound specific isotope analysis (CSIA) of stable chlorine should accordingly provide knowledge relevant to degradation rates, distribution patterns and reaction pathways for organochlorines. Isotope analysis of chlorine, derived from chlorinated hydrocarbons, can be performed using thermal ionisation mass spectrometry (TIMS) with positive ions. This lowers the limit of determination from about 30 μmol Cl for conventional electron ionisation mass spectrometry (EIMS), to less than 0.3 μmol Cl with a precision of 0.25 ppm (1s) for TIMS. Such a decrease by a factor 100 in the requirements of sample size will enable CSIA of sediment samples collected away from the immediate vicinity of strongly contaminated areas. The aim of this study is to develop a functioning sequence for i) sealed tube combustion with CuO of solid phase chlorinated hydrocarbons equivalent to <0.7 μmol Cl, ii) conversion of formed chloride to CsCl by ion exchange chromatography and iii) analysis of chlorine isotopes in TIMS. The described method can open new

  16. Recovering hydrocarbons from hydrocarbon-containing vapors

    DOEpatents

    Mirza, Zia I.; Knell, Everett W.; Winter, Bruce L.

    1980-09-30

    Values are recovered from a hydrocarbon-containing vapor by contacting the vapor with quench liquid consisting essentially of hydrocarbons to form a condensate and a vapor residue, the condensate and quench fluid forming a combined liquid stream. The combined liquid stream is mixed with a viscosity-lowering liquid to form a mixed liquid having a viscosity lower than the viscosity of the combined liquid stream to permit easy handling of the combined liquid stream. The quench liquid is a cooled portion of the mixed liquid. Viscosity-lowering liquid is separated from a portion of the mixed liquid and cycled to form additional mixed liquid.

  17. Chlorination of bisphenol A: kinetics and by-products formation.

    PubMed

    Gallard, Hervé; Leclercq, Amélie; Croué, Jean-Philippe

    2004-08-01

    The kinetics of initial chlorination of bisphenol A (BPA) was studied between pH 2 and 11 at room temperature (20 +/- 2 degrees C). pH Profile of the apparent second-order rate constant of the reaction of BPA with chlorine were modeled considering the elementary reactions of HOCl with BPA species and an acid-catalyzed reaction. The predominant reactions at near neutral pH were the reactions of HOCl with the two phenolate species of BPA (k = 3.10 x 10(4) M(-1)s(-1) for BPA- and 6.62 x 10(4) M(-1) s(-1) for BPA(2-)). At near neutral pH, half-life times of BPA were calculated to be less than 1.5 h for chlorine residual higher than 0.2 mg l(-1). Chlorination of synthetic treated waters spiked with BPA showed that BPA disappeared within 4 h and that chlorinated bisphenol A congeners were rapidly formed and remained in solution for up to 10-20 h when low chlorine dosages are applied (0.5-1 mg l(-1)). To limit their presence in drinking water networks, it is then necessary to maintain high chlorine residuals that rapidly produce and decompose chlorinated bisphenol A congeners. PMID:15212912

  18. Chlorination strategies for direct groundwater recharge of tertiary effluent

    SciTech Connect

    Fox, P.; Wang, L.; Johnson, P.C.; Houston, S.; Houston, W.N.; Brown, P.

    1998-07-01

    Chlorination for the control of biological activity during direct recharge of tertiary effluent was studied in bench-scale simulated aquifers. Both free chlorine and chloramine were studied at darcy velocities of 360 cm/d to 720 cm/d. A free chlorine residual of 5 mg/L or above inhibited biological activity in the 1.2 m of soil that was studied. A free chlorine residual concentration of 2 mg/L prevented biological activity in the first 0.9 m of exposed soil and significant biological clogging was observed in soil greater than 0.9 m from the injection point. A 2 mg/L residual concentration of chloramine resulted in biological clogging over the 0.9 m of soil adjacent to the injection point. No chlorine addition resulted in clogging adjacent to the injection point indicating that the chloramine inhibited biological activity and allowed biological activity to occur over a greater distance from the injection point. Dissolved oxygen levels decreased to zero in aquifers where significant biological activity was observed and trihalomethane concentrations decreased in these aquifers. Free chlorine appears to effectively control biological clogging adjacent to the injection point while permitting biological activity to develop after the chlorine has decayed.

  19. Water Treatment Technology - Chlorination.

    ERIC Educational Resources Information Center

    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…

  20. Inhalation of chlorine gas.

    PubMed

    Williams, J G

    1997-11-01

    The clinical features of acute chlorine gas inhalation, and its management are reviewed. Current medical views on the chronic effects of an acute overwhelming exposure on lung function (reactive airways dysfunction syndrome), and the more controversial field of lung disease secondary to repeated inhalations of lower concentrations of chlorine gas are discussed. PMID:9519180

  1. Laboratory experiments to assess the importance of photochemical transformation during the atmospheric transport of chlorinated aromatic pollutants

    SciTech Connect

    Bunce, N.J.; Landers, J.P.; Langshaw, J.A.; Nakai, J.S. )

    1987-01-01

    Chlorinated aromatic hydrocarbons are widespread and persistent pollutants. The EPA priority pollutant list (1978) mentions chlorobenzene, the three dichlorobenzenes, 1, 2, 4-trichlorobenzenes, hexachlorobenzene, and the polyclorinated biophenyls (PCB's) as examples of priority pollutants. In addition to the many studies of the biological chemistry of these chlorinated hydrocarbons, there have also been numerous photochemical studies. The justification for these photochemical studies has been that because these chlorinated hydrocarbons absorb light in the region of the solar spectrum (although very inefficiently) there may be a chance that sunlight assisted degradation is one of the routes by which these substances disappear from the environment. The authors discuss the validity of this possibility in this paper.

  2. Chlorine dioxide treatment for zebra mussel control

    SciTech Connect

    Rybarik, D.; Byron, J.; Germer, M.

    1995-06-01

    Chlorine is recognized and commonly used biocide for power plant cooling water and service water treatment programs, including the control of zebra mussels. Chlorine dioxide has recently become a popular method of zebra mussel control because of its economy, safety, environmental acceptability, and effectiveness when compared to other mussel control methods. This control technique was recently demonstrated at Dairyland Power Cooperative`s Alma Generating Station on the east bank of the upper Mississippi River in Alma, Wisconsin. The project was assisted with EPRI Tailored Collaboration Program funds. The Dairyland Power Alam Generating Station consists of five generating units that utilize raw, untreated Mississippi River water for condenser, circulating, and service water supplies. The first units were built in 1947, with the final and largest unit being completed in 1960. Total station generating capacity is 200 MW. Because of recent increases in the zebra mussel density at the station intake, Dairyland Power selected the team of Nalco and Rio Linda to perform a chlorine dioxide treatment of the station`s new water systems to eradicate and control the mussels before their presence created operational difficulties. This paper will present the results of the treatment including treatment theory, design and construction of the treatment system, the method of chlorine dioxide generation, treatment concentration, analytical methods o monitoring chlorine dioxide generation, residuals and trihalomethane (THM) concentrations, protocol for monitoring treatment mortality, and the effects of chlorine dioxide and detoxification on other water chemistry parameters and equipment materials. The goal of this paper is to inform and assist users with establishing consistent and uniform practices for safely utilizing and monitoring chlorine dioxide in the eradication and control of zebra mussels.

  3. Inactivation of Naegleria gruberi cysts by chlorinated cyanurates.

    PubMed Central

    Engel, J P; Rubin, A J; Sproul, O J

    1983-01-01

    The resistance of Naegleria gruberi cysts to chlorine in the presence of cyanuric acid was compared at pH 5 and 7. An amperometric membrane electrode was used to measure HOCl concentrations independently of the chlorinated cyanurate species, thus permitting an analysis of the role of free chlorine versus chlorinated cyanurates in cyst inactivation. In the presence of cyanuric acid, the products of the HOCl residual and the contact time required for 99% cyst inactivation were 8.5 mg . min/liter and 13.9 mg . min/liter at pH 5 and 7, respectively. The Watson's Law coefficients of dilution (n) were 1.3 and 1.6 at pH 5 and 7, respectively. The results strongly suggest that HOCl is the predominant cysticide with no measurable cysticidal effect of the chlorinated cyanurate species. PMID:6316851

  4. Turbidity and chlorine demand reduction using alum and moringa flocculation before household chlorination in developing countries.

    PubMed

    Preston, Kelsey; Lantagne, Daniele; Kotlarz, Nadine; Jellison, Kristen

    2010-03-01

    Over 1.1 billion people in the world lack access to improved drinking water. Diarrhoeal and other waterborne diseases cause an estimated 1.87 million deaths per year. The Safe Water System (SWS) is a household water treatment intervention that reduces diarrhoeal disease incidence among users in developing countries. Turbid waters pose a particular challenge to implementation of SWS programmes; although research shows that a 3.75 mg l(-1) sodium hypochlorite dose effectively treats turbid waters, users sometimes object to the strong chlorine taste and prefer to drink water that is more aesthetically pleasing. This study investigated the efficacy of two locally available chemical water treatments-alum and Moringa oleifera flocculation-to reduce turbidity and chlorine demand at turbidities of 10, 30, 70, 100 and 300 NTU. Both treatments effectively reduced turbidity (alum flocculation 23.0-91.4%; moringa flocculation 14.2-96.2%). Alum flocculation effectively reduced chlorine demand compared with controls at 30, 70, 100 and 300 NTU (p=0.01-0.06). Moringa flocculation increased chlorine demand to the point where adequate free chlorine residual was not maintained for 24 hours after treatment. Alum pretreatment is recommended in waters>or=30 NTU for optimum water disinfection. Moringa flocculation is not recommended before chlorination. PMID:20009248

  5. TECHNICAL PROTOCOL FOR EVALUATING NATURAL ATTENUATION OF CHLORINATED SOLVENTS IN GROUND WATER

    EPA Science Inventory

    This Protocol is designed to evaluate the fate in ground water of chlorinated aliphatic hydrocarbons and/or fuel hydrocarbons. Documentation of natural attenuation requires detailed site characterization. The data collected under this protocol can be used to compare the relati...

  6. New ORP/pH based control strategy for chlorination and dechlorination of wastewater: pilot scale application.

    PubMed

    Kim, H; Kwon, S; Han, S; Yu, M; Kim, J; Gong, S; Colosimo, M F

    2006-01-01

    Due to its efficiency and low capital demands, chlorination has been widely used for disinfection in many wastewater treatment plants. Since the oxidation power of free chlorine is bigger than combined chlorines which are formed from the reaction between chlorine and reducing agents in water (especially, NH4+ and organic nitrogen), for effective disinfection, excess amount of chlorine is added until all the reducing agents are oxidized and free chlorine is available. After chlorination, chlorine residues in wastewater are usually reduced with SO2 or sulfites before the treated wastewater is discharged, since they are toxic to aquatic life. Addition of excess amount of SO2 or sulfite should be avoided. Otherwise, they consume dissolved oxygen in a river or stream and may have adverse impact on the aquatic life. Determination of wastewater chlorine demand and of sulfite dosages for dechlorination has been a challenge to WWTP operators, due to the dynamic characteristics of wastewater. Recently, a new ORP/pH based approach to determine chlorine demand and sulfite dosage was proposed. The method utilizes significant points occurring on the pH and ORP profiles during chlorination and dechlorination titrations. In this study, the proposed automatic titration system has been implemented into a control system to optimize chlorine and sulfite doses for a pilot scale chlorination/dechlorination system. In short, the disinfection system with the pH/ORP based controller showed very successful results; complete inactivation of total coliforms, and almost zero residual chlorines and high DO in its effluent. PMID:16749451

  7. Evaluation of the Tenax trap in the Sample Analysis at Mars instrument suite on the Curiosity rover as a potential hydrocarbon source for chlorinated organics detected in Gale Crater

    NASA Astrophysics Data System (ADS)

    Miller, Kristen E.; Kotrc, Benjamin; Summons, Roger E.; Belmahdi, Imene; Buch, Arnaud; Eigenbrode, Jennifer L.; Freissinet, Caroline; Glavin, Daniel P.; Szopa, Cyril

    2015-08-01

    The Sample Analysis at Mars (SAM) instrument suite aboard Curiosity has detected chlorinated organic compounds in Martian sediment samples. The chlorine in these molecules is thought to derive from oxychlorine salts in Martian sediments, but the carbon source remains under investigation. To constrain possible carbon sources, we investigated how the composition and concentration of oxychlorine phases in solid samples affect organic molecules released from the Tenax traps on board SAM. We created Mars analogue soils by spiking olivine sand with calcium perchlorate, magnesium perchlorate, or ferric iron chloride and analyzed the volatiles generated during pyrolysis-gas chromatography-mass spectrometry using commercial instruments operated under SAM-like conditions, with and without a Tenax trap. Benzoic acid, phthalic anhydride, high molecular weight aromatics, and chlorobenzenes are produced from the trap in response to volatiles released during Cl salt pyrolysis. Changes in composition or concentration of oxychlorine phases between samples could thus potentially produce an increase in chlorobenzene, as observed between samples from Rocknest and Cumberland. However, in our experiments benzoic acid, phthalic anhydride, and chlorobenzenes increase in proportion with the amount of HCl sent to the trap, while in Cumberland samples the chlorobenzene increase showed no corresponding increase in HCl. Based on our experiments, the Tenax trap is a possible source of the traces of chlorobenzene observed at Rocknest, John Klein, and Confidence Hills. The order-of-magnitude higher chlorobenzene abundances observed at Cumberland cannot be attributed to the Tenax trap. Furthermore, we found no evidence of significant trap degradation after hundreds of experiments with Cl salt-containing analogue soils.

  8. Assessing fuel spill risks in polar waters: Temporal dynamics and behaviour of hydrocarbons from Antarctic diesel, marine gas oil and residual fuel oil.

    PubMed

    Brown, Kathryn E; King, Catherine K; Kotzakoulakis, Konstantinos; George, Simon C; Harrison, Peter L

    2016-09-15

    As part of risk assessment of fuel oil spills in Antarctic and subantarctic waters, this study describes partitioning of hydrocarbons from three fuels (Special Antarctic Blend diesel, SAB; marine gas oil, MGO; and intermediate grade fuel oil, IFO 180) into seawater at 0 and 5°C and subsequent depletion over 7days. Initial total hydrocarbon content (THC) of water accommodated fraction (WAF) in seawater was highest for SAB. Rates of THC loss and proportions in equivalent carbon number fractions differed between fuels and over time. THC was most persistent in IFO 180 WAFs and most rapidly depleted in MGO WAF, with depletion for SAB WAF strongly affected by temperature. Concentration and composition remained proportionate in dilution series over time. This study significantly enhances our understanding of fuel behaviour in Antarctic and subantarctic waters, enabling improved predictions for estimates of sensitivities of marine organisms to toxic contaminants from fuels in the region. PMID:27389459

  9. CHLORINATED SOLVENT PLUME CONTROL

    EPA Science Inventory

    This lecture will cover recent success in controlling and assessing the treatment of shallow ground water plumes of chlorinated solvents, other halogenated organic compounds, and methyl tert-butyl ether (MTBE).

  10. Breathing with chlorinated solvents

    SciTech Connect

    McCarty, P.L.

    1997-06-06

    Chlorinated solvents are effective cleaners and in the past dirted solvents were dumped into landfills, stored in tanks that often leaked, or spilled. As a result the most common contaminants of organic groundwater at hazardous waste sites are the two major chlorinated solvents - tetrachloroethylene (PCE) and trichloroethylene (TCE). Both are suspected carcinogens and both are highly resistant to biodegradation. Now however, there is a report of a bacterium that can remove all of the chlorine atoms from both by halorespiration to form ethene, an innocuous end product. This article goes on to discuss the background of biodegradation of chlorinated compounds, why it is so difficult, and what the future is in this area. 9 refs., 1 fig.

  11. Sarcoendoplasmic reticulum Ca(2+) ATPase. A critical target in chlorine inhalation-induced cardiotoxicity.

    PubMed

    Ahmad, Shama; Ahmad, Aftab; Hendry-Hofer, Tara B; Loader, Joan E; Claycomb, William C; Mozziconacci, Olivier; Schöneich, Christian; Reisdorph, Nichole; Powell, Roger L; Chandler, Joshua D; Day, Brian J; Veress, Livia A; White, Carl W

    2015-04-01

    Autopsy specimens from human victims or experimental animals that die due to acute chlorine gas exposure present features of cardiovascular pathology. We demonstrate acute chlorine inhalation-induced reduction in heart rate and oxygen saturation in rats. Chlorine inhalation elevated chlorine reactants, such as chlorotyrosine and chloramine, in blood plasma. Using heart tissue and primary cardiomyocytes, we demonstrated that acute high-concentration chlorine exposure in vivo (500 ppm for 30 min) caused decreased total ATP content and loss of sarcoendoplasmic reticulum calcium ATPase (SERCA) activity. Loss of SERCA activity was attributed to chlorination of tyrosine residues and oxidation of an important cysteine residue, cysteine-674, in SERCA, as demonstrated by immunoblots and mass spectrometry. Using cardiomyocytes, we found that chlorine-induced cell death and damage to SERCA could be decreased by thiocyanate, an important biological antioxidant, and by genetic SERCA2 overexpression. We also investigated a U.S. Food and Drug Administration-approved drug, ranolazine, used in treatment of cardiac diseases, and previously shown to stabilize SERCA in animal models of ischemia-reperfusion. Pretreatment with ranolazine or istaroxime, another SERCA activator, prevented chlorine-induced cardiomyocyte death. Further investigation of responsible mechanisms showed that ranolazine- and istaroxime-treated cells preserved mitochondrial membrane potential and ATP after chlorine exposure. Thus, these studies demonstrate a novel critical target for chlorine in the heart and identify potentially useful therapies to mitigate toxicity of acute chlorine exposure. PMID:25188881

  12. Sarcoendoplasmic Reticulum Ca2+ ATPase. A Critical Target in Chlorine Inhalation–Induced Cardiotoxicity

    PubMed Central

    Ahmad, Aftab; Hendry-Hofer, Tara B.; Loader, Joan E.; Claycomb, William C.; Mozziconacci, Olivier; Schöneich, Christian; Reisdorph, Nichole; Powell, Roger L.; Chandler, Joshua D.; Day, Brian J.; Veress, Livia A.; White, Carl W.

    2015-01-01

    Autopsy specimens from human victims or experimental animals that die due to acute chlorine gas exposure present features of cardiovascular pathology. We demonstrate acute chlorine inhalation–induced reduction in heart rate and oxygen saturation in rats. Chlorine inhalation elevated chlorine reactants, such as chlorotyrosine and chloramine, in blood plasma. Using heart tissue and primary cardiomyocytes, we demonstrated that acute high-concentration chlorine exposure in vivo (500 ppm for 30 min) caused decreased total ATP content and loss of sarcoendoplasmic reticulum calcium ATPase (SERCA) activity. Loss of SERCA activity was attributed to chlorination of tyrosine residues and oxidation of an important cysteine residue, cysteine-674, in SERCA, as demonstrated by immunoblots and mass spectrometry. Using cardiomyocytes, we found that chlorine-induced cell death and damage to SERCA could be decreased by thiocyanate, an important biological antioxidant, and by genetic SERCA2 overexpression. We also investigated a U.S. Food and Drug Administration–approved drug, ranolazine, used in treatment of cardiac diseases, and previously shown to stabilize SERCA in animal models of ischemia–reperfusion. Pretreatment with ranolazine or istaroxime, another SERCA activator, prevented chlorine-induced cardiomyocyte death. Further investigation of responsible mechanisms showed that ranolazine- and istaroxime-treated cells preserved mitochondrial membrane potential and ATP after chlorine exposure. Thus, these studies demonstrate a novel critical target for chlorine in the heart and identify potentially useful therapies to mitigate toxicity of acute chlorine exposure. PMID:25188881

  13. A LONG-LIFE, LOW-COST SORBENT FOR THE CONVERSION OF HCL TO CHLORINE - PHASE II

    EPA Science Inventory

    The U.S. demand for chlorinated hydrocarbons exceeds 15 million tons annually. The production of these chemicals requires elemental chlorine and unavoidably produces HCl as a byproduct (35 to 50% of input Cl2). A consortium of major chemical companies is developing a sor...

  14. Impact of water quality on chlorine demand of corroding copper.

    PubMed

    Lytle, Darren A; Liggett, Jennifer

    2016-04-01

    Copper is widely used in drinking water premise plumbing system materials. In buildings such as hospitals, large and complicated plumbing networks make it difficult to maintain good water quality. Sustaining safe disinfectant residuals throughout a building to protect against waterborne pathogens such as Legionella is particularly challenging since copper and other reactive distribution system materials can exert considerable demands. The objective of this work was to evaluate the impact of pH and orthophosphate on the consumption of free chlorine associated with corroding copper pipes over time. A copper test-loop pilot system was used to control test conditions and systematically meet the study objectives. Chlorine consumption trends attributed to abiotic reactions with copper over time were different for each pH condition tested, and the total amount of chlorine consumed over the test runs increased with increasing pH. Orthophosphate eliminated chlorine consumption trends with elapsed time (i.e., chlorine demand was consistent across entire test runs). Orthophosphate also greatly reduced the total amount of chlorine consumed over the test runs. Interestingly, the total amount of chlorine consumed and the consumption rate were not pH dependent when orthophosphate was present. The findings reflect the complex and competing reactions at the copper pipe wall including corrosion, oxidation of Cu(I) minerals and ions, and possible oxidation of Cu(II) minerals, and the change in chlorine species all as a function of pH. The work has practical applications for maintaining chlorine residuals in premise plumbing drinking water systems including large buildings such as hospitals. PMID:26826646

  15. DISINFECTION EFFICIENCY AND RESIDUAL TOXICITY OF SEVERAL WASTEWATER DISINFECTANTS. VOLUME I. GRANDVILLE, MICHIGAN

    EPA Science Inventory

    This study was conducted to determine the comparative effectiveness of chlorine, bromine chloride, and ozone as wastewater disinfectants, and to determine any residual toxicity associated with wastewater disinfection with these agents or with chlorinated wastewater which had been...

  16. Chlorinated degreasing solvents: Physical-chemical properties affecting aquifer contamination and remediation

    SciTech Connect

    Jackson, R.E.; Dwarakanath, V.

    1999-09-30

    Chlorinated degreasing solvents are multicomponent liquids containing not only the chlorinated hydrocarbons with which their name is associated (e.g., trichloroethylene or [TCE], perchloroethylene or [PCE], 1,1,1-trichloroethane [TCA]) but also a number of organic additives included as corrosion inhibitors and antioxidants. The additives, such as 1,4-dioxane, are likely to be of significant public-health importance as ground water contaminants due to their toxicity, solubility, and mobility. Following their use in vapor degreasing systems by industry, chlorinated degreasing solvents will also contain about 25% solubilized oil and grease. A number of physical-chemical properties become especially important in the light of the multicomponent nature of these solvents. First, the higher aqueous solubility and lower sorption of the additives makes it reasonable to expect that faster moving plumes of these solvent additives will precede plumes of the chlorinated hydrocarbons. Second, due to high losses of chlorinated hydrocarbons by volatilization from vapor degreasers during years in the middle of the century, it is probable that background concentrations of these hydrocarbons are present in ground water flow systems due to their downwind washout. Finally, the solubilized oil and grease may cause profound changes to the wettability of aquifer materials contacted by the solvents during their subsurface migration. It is argued, therefore, that the wettability of aquifer materials contaminated by chlorinated degreasing solvents needs to be experimentally determined before remediation of DNAPL at each site, rather than being simply assumed as water wet.

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

    NASA Astrophysics Data System (ADS)

    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.

  18. Solid organic residues produced by irradiation of hydrocarbon-containing H2O and H2O/NH3 ices - Infrared spectroscopy and astronomical implications

    NASA Technical Reports Server (NTRS)

    Khare, B. N.; Thompson, W. R.; Murray, B. G. J. P. T.; Chyba, C. F.; Sagan, C.

    1989-01-01

    Plasma-discharge irradiations were conducted for the methane clathrate expected in outer solar system satellites and cometary nuclei; also irradiated were ices prepared from other combinations of H2O with CH4, C2H6, or C2H2. Upon evaporation of the yellowish-to-tan irradiated ices, it is found that a colored solid film adheres to the walls of the reaction vessel at room temperature. These organic films are found to exhibit IR band identifiable with alkane, aldehide, alcohol, and perhaps alkene, as well as substituted aromatic functional groups. These spectra are compared with previous studies of UV- or photon-irradiated nonclathrated hydrocarbon-containing ices.

  19. Bioremediation of chlorinated solvents and diesel soils

    SciTech Connect

    Huismann, S.S.; Peterson, M.A.; Jardine, R.J.

    1995-11-01

    The US Army, in a cooperative effort with the Tennessee Valley Authority (TVA) and its cooperator, ENSR, performed an innovative enhanced bioremediation project at Fort Gillem in Atlanta, Georgia. The objective of the project was to remediate six hundred cubic yards of soil affected by a mixture of chlorinated compounds and petroleum hydrocarbons which posed a threat to uppermost groundwater and private drinking water wells. ENSR completed a demonstration project to measure the effects of bioremediation on both chlorinated compounds (primarily TCE) and petroleum hydrocarbons ({number_sign}2 diesel). Contaminated soil was placed on top of a bermed polyethylene liner to construct an ex-situ biovault. Nutrients were added to the soil as it was loaded onto the liner. Contaminated soil was also used to construct a control vault. A methane barrier cover was placed over both piles. The cover was designed to prevent short circuiting of induced airflow in and around the enhanced pile, and to prevent the release of fugitive emissions from either pile.

  20. Hydrodesulfurization of chlorinized coal

    NASA Technical Reports Server (NTRS)

    Kalvinskas, J. J.; Rohatgi, N. K. (Inventor)

    1983-01-01

    A method of desulfurization is described in which high sulfur coals are desulfurized by low temperature chlorinolysis of coal in liquid media, preferably water, followed by hydrodesulfurization at a temperature above 500 C. The coals are desulfurized to an extent of up to 90% by weight and simultaneously dechlorinated to a chlorine content below 0.1% by weight. The product coals have lower volatiles loss, lower oxygen and nitrogen content and higher fixed carbon than raw coals treated with hydrogen under the same conditions. Heating the chlorinated coal to a temperature above 500 C. in inert gas such as nitrogen results in significantly less desulfurization.

  1. EFFECT OF THE DECHLORINATING AGENT, ASCORBIC ACID, ON THE MUTAGENICITY OF CHLORINATED WATER SAMPLES

    EPA Science Inventory

    XAD resin adsorption has been widely used to concentrate the organic compounds present in chlorinated drinking waters prior to mutagenicity testing. Previous work has shown that mutagenic artifcats can arise due to the reaction of residual chlorine with the resins. Althrough the ...

  2. The synergistic effect of Escherichia coli inactivation by sequential disinfection with low level chlorine dioxide followed by free chlorine.

    PubMed

    Yang, Wu; Yang, Dong; Zhu, Sui-Yi; Chen, Bo-Yan; Huo, Ming-Xin; Li, Jun-Wen

    2012-12-01

    To the best of our knowledge, there was little information available on pathogen removal using low level disinfectant followed by free chlorine in sequential disinfection (SD). This study investigated Escherichia coli inactivation by four types of disinfection: single step disinfection (SSD), SD, traditional sequential disinfection (TSD) and mixed disinfectant disinfection (MDD). Results indicated that SD had higher ability to inactivate E. coli than the others, indicating there was a positive synergistic effect on chlorine disinfection by prior dosing with a low level of chlorine dioxide (ClO(2)). The ONPG assay suggested that the permeability of cell wall rather than the viability of E. coli were changed under 0.02 mg/l ClO(2) treatment. The coexistence of residual ClO(2) and free chlorine also plays an active synergistic effect. Additionally, temperature had a positive effect on E. coli inactivation in SD, while inactivation was reduced in alkaline compared to neutral and acidic conditions. PMID:23165713

  3. Tolerance of five species of tropical marine mussels to continuous chlorination.

    PubMed

    Rajagopal, S; Venugopalan, V P; Van der Velde, G; Jenner, H A

    2003-05-01

    The paper examines the relative lethal and sublethal response of five important tropical marine mussels (Perna viridis, Perna perna, Brachidontes striatulus, Brachidontes variabilis and Modiolus philippinarum) to different chlorine concentrations varying from 0.25 to 15 mg l(-1). The mussels were observed to co-exist in the cooling water circuits of a coastal power station that adopted intermittent chlorination as a fouling control technique. The five mussel species showed, in response to chlorination, 100% mortality at significantly different exposure times, indicating significant species-specific variability in chlorine tolerance. For example, at 1 mg l(-1) residual chlorine, B. variabilis and P. viridis took 288 and 816 h, respectively, to achieve 100% mortality. The time taken for 100% mortality decreased with increasing chlorine residual concentration. The effect of mussel size (= mussel age) of P. viridis, P. perna, B. striatulus and M. philippinarum on mortality was significant between 1 and 5 mg l(-1) residual chlorine, with larger mussels showing greater resistance than smaller ones. All mussel species showed progressive reduction in physiological activities when chlorine residuals were increased from 0 to 1 mg l(-1). However, species-specific differences in the relative rate of physiological activities were observed. Accordingly, relative reduction in physiological activities in response to chlorination was the lowest in P. viridis and the highest in B. variabilis. The data clearly indicate significant differences in the lethal and sublethal responses of the five mussel species to chlorination. The results, therefore, suggest that for effective fouling control, chlorine treatment against mussels has to be employed judiciously, depending on the mussel species involved. PMID:12517421

  4. Chlorine Dioxide (Gas)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chlorine dioxide (ClO2) gas is registered by the U.S. Environmental Protection Agency (EPA) as a sterilant for use in manufacturing, laboratory equipment, medical devices, environmental surfaces, tools and clean rooms. Aqueous ClO2 is registered by the EPA as a surface disinfectant and sanitizer fo...

  5. Chlorination of lanthanum oxide.

    PubMed

    Gaviría, Juan P; Navarro, Lucas G; Bohé, Ana E

    2012-03-01

    The reactive system La(2)O(3)(s)-Cl(2)(g) was studied in the temperature range 260-950 °C. The reaction course was followed by thermogravimetry, and the solids involved were characterized by X-ray diffraction, scanning electron microscopy, and energy dispersive spectroscopy. The results showed that the reaction leads to the formation of solid LaOCl, and for temperatures above 850 °C, the lanthanum oxychloride is chlorinated, producing LaCl(3)(l). The formation of the oxychloride progresses through a nucleation and growth mechanism, and the kinetic analysis showed that at temperatures below 325 °C the system is under chemical control. The influence of diffusive processes on the kinetics of production of LaOCl was evaluated by studying the effect of the reactive gas flow rate, the mass of the sample, and the chlorine diffusion through the boundary layer surrounding the solid sample. The conversion curves were analyzed and fitted according to the Johnson-Mehl-Avrami description, and the reaction order with respect to the chlorine partial pressure was obtained by varying this partial pressure between 10 and 70 kPa. The rate equation was obtained, which includes the influence of the temperature, chlorine partial pressure, and reaction degree. PMID:22280490

  6. Chlorine dioxide and hemodialysis

    SciTech Connect

    Smith, R.P. . Dept. of Pharmacology and Toxicology)

    1989-05-01

    Because it has little or no tendency to generate carcinogenic trihalomethanes such as chloroform, chlorine dioxide is an attractive alternative to chlorine for drinking water disinfection. There are, however, concerns about its acute toxicity, and the toxic effects of its by-products, chlorite and chlorate. The human experience with chlorine dioxide in both controlled, prospective studies and in actual use situations in community water supplies have as yet failed to reveal adverse health effects. The EPA has recommended standards of 0.06 mg/L for chlorine dioxide and standards of 0.007 mg/L for chlorite and chlorate in drinking water. Among groups who may be at special risk from oxychlorines in drinking water are patients who must undergro chronic extracorporeal hemodialysis. Although even units for home hemodialysis are supposed to be equipped with devices which effectively remove oxychlorines, there is a always a possibility of operator error or equipment failure. When the equipment is adequately maintained, it is likely that dialysis patients will have more intensive exposures from drinking water than from dialysis fluids despite the much larger volumes of water that are involved in dialysis. This paper discusses a hemodialysis and the standards and effects of oxychlorines. 90 refs., 2 tabs.

  7. Influence of Other Contaminants on Natural Attenuation of Chlorinated Solvents

    SciTech Connect

    Kinsall, B.L.; Palumbo, A.V.; Pfiffner, S.M.; Phelps, T.J.; Salpas, P.

    1999-04-19

    Studies at numerous sites have shown high variability in the degradation rates of chlorinated solvents as measured by microcosm studies with 14C labeled contaminants. The ability of nutrient and carbon additions to stimulate degradation can vary widely. Although some of these variations can be related to the structure of the extant microbial community, the presence of other less refractory contaminants may be critical fctors impacting the rate of chlorocarbon mineralization. Relaatively highe rates of TCE degradation have been observed in the DOE K-25 burial grounds with diverse organic loadings as well as in areas that show evidence for hydrocarbon contamination. Similarly, at other sites where there was TCE in the absence of hydrocarbons or other contaminants, the measured degradation rates have often been found to be very low. At various other sites, the intrasite variability in degradation rates appeared to be related to the presence of hydrocarbon contamination. The highest rates were observed at sites with evidence of hydrocarbons. These observations indicated that the viability of natural attenuation as a remediation option for chlorinated solvents might depend in part on the presence co-contaminants such as hydrocarbons or natural matter.

  8. RESPONSES OF EARLY LIFE HISTORY STAGES OF THE STRIPED BASS, 'MORONE SAXATILIS' TO CHLORINATION

    EPA Science Inventory

    The toxicity of total residual chlorination (TRC) to early life stages of the striped bass, Morone saxatilis, was determined using percent embryo hatchability, incipient LC50 bioassays, histopathology, and avoidance responses. Beginning 8 to 9 hours after fertilization, developin...

  9. PCB removal by conventional water treatment: effect of chemical coagulation and chlorination

    SciTech Connect

    Aly, O.A.; Badawy, M.I.

    1986-06-01

    Previous studies revealed that residue levels of PCBs in the drinking waters in Egypt tend to exceed the permissible levels. This study evaluated the efficiency of coagulation and chlorination for removal of PCBs from drinking water.

  10. Characterisation of polycyclic aromatic hydrocarbons in flue gas and residues of a full scale fluidized bed combustor combusting non-hazardous industrial waste.

    PubMed

    Van Caneghem, J; Vandecasteele, C

    2014-11-01

    This paper studies the fate of PAHs in full scale incinerators by analysing the concentration of the 16 EPA-PAHs in both the input waste and all the outputs of a full scale Fluidized Bed Combustor (FBC). Of the analysed waste inputs i.e. Waste Water Treatment (WWT) sludge, Refuse Derived Fuel (RDF) and Automotive Shredder Residue (ASR), RDF and ASR were the main PAH sources, with phenanthrene, fluoranthene and pyrene being the most important PAHs. In the flue gas sampled at the stack, naphthalene was the only predominant PAH, indicating that the PAHs in FBC's combustion gas were newly formed and did not remain from the input waste. Of the other outputs, the boiler and fly ash contained no detectable levels of PAHs, whereas the flue gas cleaning residue contained only low concentrations of naphthalene, probably adsorbed from the flue gas. The PAH fingerprint of the bottom ash corresponded rather well to the PAH fingerprint of the RDF and ASR, indicating that the PAHs in this output, in contrast to the other outputs, were mainly remainders from the PAHs in the waste inputs. A PAH mass balance showed that the total PAH input/output ratio of the FBC ranged from about 100 to about 2600 depending on the waste input composition and the obtained combustion conditions. In all cases, the FBC was clearly a net PAH sink. PMID:25002370

  11. 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.

    PubMed

    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 (p<0.05) in turtles from the Turkey Creek and Muddy Creek-Wheatley Harbour sites in Lake 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

  12. Chlorine resistance of poliovirus isolants recovered from drinking water.

    PubMed Central

    Shaffer, P T; Metcalf, T G; Sproul, O J

    1980-01-01

    Poliovirus 1 isolants were recovered from finished drinking water produced by a modern, well-operated water treatment plant. These waters contained free chlorine residuals in excess of 1 mg/liter. The chlorine inactivation of purified high-titer preparations of two such isolants was compared with the inactivation behavior of two stock strains of poliovirus 1, LSc and Mahoney. The surviving fraction of virus derived from the two natural isolants was shown to be orders of magnitude greater than that of the standard strains. These results raise the question whether indirect drinking water standards based on free chlorine residuals are adequate public health measures, or whether direct standards based on virus determinations might be necessary. Images PMID:6257162

  13. Environmental availability of chlorinated organics, explosives, and metals in soils

    SciTech Connect

    Anderson, W.C.; Loehr, R.C.; Smith, B.P.

    1999-08-01

    Environmental availability is key to defining the extent of remediation required. Nationally recognized experts summarize what is known about the environmental availability of chlorinated organics (Perry McCarty), explosives (Judith Pennington), and metals (Rufus Chaney). It also summarizes the current use of environmental availability to set cleanup goals for petroleum hydrocarbons and identifies essential research needed to expand the knowledge base for environmental availability.

  14. Efficacy of chlorine disinfection of soft contact lenses.

    PubMed

    Ferreira, J T; Kriel, F; van der Merwe, D; Pheiffer, G

    1991-09-01

    We evaluated the chlorine system SOFTAB (Alcon) for the disinfection of soft contact lenses. The results indicate that a 1000-fold reduction in microorganisms was achieved within 6 h. Even with the slight interference of residual cleaner and the more significant interference of organic matter disinfection was still achieved. PMID:1745498

  15. Chlorine Analysis - Wastewater. Training Module 5.125.2.77.

    ERIC Educational Resources Information Center

    Kirkwood Community Coll., Cedar Rapids, IA.

    This document is an instructional module package prepared in objective form for use by an instructor familiar with the laboratory procedures for determining the combined chlorine residual of a wastewater sample. Included are objectives, instructor guides, student handouts, and transparency masters. This module considers the amperometric, DPD,…

  16. TOXICITY OF CHLORINE TO JUVENILE SPOT, LEIOSTOMUS XANTHURUS

    EPA Science Inventory

    The sensitivity of juvenile spot, Leiostomus xanthurus, to total residual chlorine (TRC) in flowing sea-water was investigated. Incipient LC50 bioassays, histopathology, avoidance tests and the combined effect of thermal stress and TRC were used to assess sensitivity. Estimated i...

  17. Performance and reliability improvement of HfSiON gate dielectrics using chlorine plasma treatment

    SciTech Connect

    Park, Hong Bae; Ju, Byongsun; Kang, Chang Yong; Park, Chanro; Park, Chang Seo; Lee, Byoung Hun; Kim, Tea Wan; Kim, Beom Seok; Choi, Rino

    2009-01-26

    The effects of chlorine plasma treatment on HfSiON gate dielectrics were investigated with respect to device performance and reliability characteristics. The chlorine plasma treatment was performed on atomic layer deposited HfSiON films to remove the residual carbon content. The optimal chlorine plasma treatment is shown to lower gate leakage current density without increasing equivalent oxide thickness of the gate stack. Secondary ion mass spectroscopy depth profiling showed that the carbon residue in HfSiON was reduced by the chlorine plasma treatment. It is demonstrated that an optimized chlorine plasma treatment improves the transistor I{sub on}-I{sub off} characteristics and reduces negative-bias temperature instability.

  18. Different removal behaviours of multiple trace antibiotics in municipal wastewater chlorination.

    PubMed

    Li, Bing; Zhang, Tong

    2013-06-01

    The chlorination behaviours of 12 antibiotics belonging to six classes at environmentally relevant concentrations were systematically examined under typical conditions relevant to municipal wastewater chlorination. Cefotaxime, cefalexin, ampicillin and tetracycline were completely removed under all three initial free chlorine dosages (5 mg/L, 10 mg/L, and 15 mg/L). The removal efficiencies of sulphamethoxazole, sulphadiazine, roxithromycin, anhydro-erythromycin, ofloxacin, and trimethoprim were closely correlated to the residual free chlorine concentration, and no further significant mass removal was observed after the residual free chlorine concentration decreased to less than ≈ 0.75 mg/L. Ammonia plays a critical role during chlorination because of its competition with antibiotics for free chlorine to form combined chlorine, which reacts slowly with these antibiotics. Except for norfloxacin and ciprofloxacin, the removal behaviours of the 10 other target antibiotics under ammonia nitrogen concentrations ranging from 2 to 15 mg/L were characterised by a rapid initial removal rate upon contact with free chlorine during the first 5 s-1 min (depending on the specific antibiotic and ammonia nitrogen concentration) and then a much slower removal rate. Free chlorine was responsible for the reaction with antibiotics during the rapid stage (first 5 s-1 min), whereas combined chlorine reacted with antibiotics in the subsequent slow stage. Combined chlorine can remove norfloxacin and ciprofloxacin at a relatively faster rate. The presence of suspended solids at 30 mg/L slightly decreased the antibiotic removal rate. The kinetic rate constants decreased by 2.1-13.9%, while the half-lives increased by 2.0-15.0% compared to those of a 0 mg/L suspended solid for the target antibiotics. PMID:23587262

  19. Bacterial repopulation of drinking water pipe walls after chlorination.

    PubMed

    Mathieu, Laurence; Francius, Grégory; El Zein, Racha; Angel, Edith; Block, Jean-Claude

    2016-09-01

    The short-term kinetics of bacterial repopulation were evaluated after chlorination of high-density polyethylene (HDPE) colonized with drinking water biofilms and compared with bare HDPE surfaces. The effect of chlorination was partial as a residual biofilm persisted and was time-limited as repopulation occurred immediately after water resupply. The total number of bacteria reached the same levels on both the bare and chlorinated biofilm-fouled HDPE after a seven-day exposure to drinking water. Due to the presence of a residual biofilm, the hydrophobicity of chlorinated biofilm-fouled surface exhibited much lower adhesion forces (2.1 nN) compared to bare surfaces (8.9 nN). This could explain the rapid repopulation after chlorination, with a twofold faster bacterial accumulation rate on the bare HDPE surface. γ-Proteobacteria dominated the early stages of repopulation of both surfaces and a shift in the dominance occurred over the colonization time. Such observations define a timescale for cleaning frequency in industrial environments and guidelines for a rinsing procedure using drinking water. PMID:27483985

  20. EFFECTS OF OZONE, CHLORINE DIOXIDE, CHLORINE, AND MONOCHLORAMINE ON CRYPTOSPORIDIUM PARVUM OOCYST VIABILITY

    EPA Science Inventory

    Purified Cryptosporidium parvum oocysts were exposed to ozone, chlorine dioxide, chlorine, and monochloramine. xcystation and mouse infectivity were comparatively evaluated to assess oocyst viability. zone and chlorine dioxide more effectively inactivated oocysts than chlorine an...

  1. Achieving second order advantage with multi-way partial least squares and residual bi-linearization with total synchronous fluorescence data of monohydroxy-polycyclic aromatic hydrocarbons in urine samples.

    PubMed

    Calimag-Williams, Korina; Knobel, Gaston; Goicoechea, H C; Campiglia, A D

    2014-02-01

    An attractive approach to handle matrix interference in samples of unknown composition is to generate second- or higher-order data formats and process them with appropriate chemometric algorithms. Several strategies exist to generate high-order data in fluorescence spectroscopy, including wavelength time matrices, excitation-emission matrices and time-resolved excitation-emission matrices. This article tackles a different aspect of generating high-order fluorescence data as it focuses on total synchronous fluorescence spectroscopy. This approach refers to recording synchronous fluorescence spectra at various wavelength offsets. Analogous to the concept of an excitation-emission data format, total synchronous data arrays fit into the category of second-order data. The main difference between them is the non-bilinear behavior of synchronous fluorescence data. Synchronous spectral profiles change with the wavelength offset used for sample excitation. The work presented here reports the first application of total synchronous fluorescence spectroscopy to the analysis of monohydroxy-polycyclic aromatic hydrocarbons in urine samples of unknown composition. Matrix interference is appropriately handled by processing the data either with unfolded-partial least squares and multi-way partial least squares, both followed by residual bi-linearization. PMID:24456595

  2. Selected alternatives to conventional chlorination. Final report

    SciTech Connect

    Garey, J.F.

    1980-10-01

    This study was jointly funded by EPRI and five electric utility companies in New England (New England Power, Northeast Utilities, United Illuminating, Vermont Yankee Nuclear, and Public Service of New Hampshire). Previous investigations had identified three major areas for further study: continuous low-level chlorination, dechlorination, and condenser biofouling control. Continuous low-level chlorination, studied at two locations, one on open coastal water and the other in an industrialized estuarine area, showed that 0.1 ppM total residual oxidant (TRO) prevented attachment of the blue mussel (Mytilus edulis) to concrete surfaces. Chronic bioassays showed that 0.075 ppM TRO reduced biofouling by indigenous organisms; 0.1 ppM TRO slightly increased mortalities of the Atlantic silversides (Menidia menidia) but had no effect on the American oyster (Crassostrea virginica). Dechlorination investigations showed that threespine sticklebacks (Gasterosteus aculeatus), Atlantic silversides (Menidia menidia), larval bay scallops (Argopecten irradians), and the copepod Acartia tonsa exposed to water chlorinated to 0.5 ppM TRO for 10, 100, and 1000 seconds, followed by dechlorination with sodium thiosulfate, all suffered significant toxic effects. Condenser tube biofouling studies showed that there was a strong correlation between condenser performance and condenser tube biofouling; biofilm induction varied inversely with ambient water temperature, but orientation of the tubes had no effect on biofilm formation; and all chemicals tested (mono-, di-, and trisodium phosphate; Polident; and TRO at 0.1 ppM) reduced but did not remove biofilms.

  3. Oxidation of manganese(II) during chlorination: role of bromide.

    PubMed

    Allard, S; Fouche, L; Dick, J; Heitz, A; von Gunten, U

    2013-08-01

    The oxidation of dissolved manganese(II) (Mn(II)) during chlorination is a relatively slow process which may lead to residual Mn(II) in treated drinking waters. Chemical Mn(II) oxidation is autocatalytic and consists of a homogeneous and a heterogeneous process; the oxidation of Mn(II) is mainly driven by the latter process. This study demonstrates that Mn(II) oxidation during chlorination is enhanced in bromide-containing waters by the formation of reactive bromine species (e.g., HOBr, BrCl, Br2O) from the oxidation of bromide by chlorine. During oxidation of Mn(II) by chlorine in bromide-containing waters, bromide is recycled and acts as a catalyst. For a chlorine dose of 1 mg/L and a bromide level as low as 10 μg/L, the oxidation of Mn(II) by reactive bromine species becomes the main pathway. It was demonstrated that the kinetics of the reaction are dominated by the adsorbed Mn(OH)2 species for both chlorine and bromine at circumneutral pH. Reactive bromine species such as Br2O and BrCl significantly influence the rate of manganese oxidation and may even outweigh the reactivity of HOBr. Reaction orders in [HOBr]tot were found to be 1.33 (±0.15) at pH 7.8 and increased to 1.97 (±0.17) at pH 8.2 consistent with an important contribution of Br2O which is second order in [HOBr]tot. These findings highlight the need to take bromide, and the subsequent reactive bromine species formed upon chlorination, into account to assess Mn(II) removal during water treatment with chlorine. PMID:23859083

  4. Process for converting light alkanes to higher hydrocarbons

    DOEpatents

    Noceti, Richard P.; Taylor, Charles E.

    1988-01-01

    A process is disclosed for the production of aromatic-rich, gasoline boiling range hydrocarbons from the lower alkanes, particularly from methane. The process is carried out in two stages. In the first, alkane is reacted with oxygen and hydrogen chloride over an oxyhydrochlorination catalyst such as copper chloride with minor proportions of potassium chloride and rare earth chloride. This produces an intermediate gaseous mixture containing water and chlorinated alkanes. The chlorinated alkanes are contacted with a crystalline aluminosilicate catalyst in the hydrogen or metal promoted form to produce gasoline range hydrocarbons with a high proportion of aromatics and a small percentage of light hydrocarbons (C.sub.2 -C.sub.4). The light hydrocarbons can be recycled for further processing over the oxyhydrochlorination catalyst.

  5. Metal loaded zeolitic media for the storage and oxidative destruction of chlorinated VOCs

    NASA Astrophysics Data System (ADS)

    Chintawar, Prashant Shiodas

    Industrial solvents such as trichloroethylene (TCE), perchloroethylene (PCE), etc. are suspected carcinogens and are linked to atmospheric and groundwater pollution. Therefore, the destruction and/or safe disposal of these chlorinated volatile organic compounds (CVOCs) is an immediate national need. The objective of this dissertation was to study transition metal (TM) loaded zeolites for adsorption (storage) and subsequent catalytic destruction of CVOCs present in humid air streams. In this study, zeolite Y, ZSM-5 and ETS-10 were modified by introduction of a TM cation to make them suitable as dual function sorbent/catalyst (S/C) media. In order to develop these S/C media, five investigations were carried out. In the first investigation, the activity and selectivity of three catalysts viz., Cr-Y, Co-Y, Co/Alsb2Osb3, was compared for the destruction of CVOCs. Cr-Y was the most promising catalyst with its activity decreasing with an increase in the chlorine content of the CVOC molecule. In the second investigation, in order to elucidate the pathways involved in the destruction of CVOCs, in situ FT-IR studies were carried out on active Cr-Y surfaces at 25, 100 (or 130) and 300sp°C which showed that CVOC destruction proceeded through the formation of oxygenated intermediates (carbonyl, carboxylate, etc.). These investigations showed the necessity of chromium for destruction of CVOCs. However, chromium residues in the spent catalysts are an environmental concern. Therefore, in the third investigation, attempts were made to stabilize low levels of chromium on ZSM-5 zeolites. Thus, Cr-ZSM-5 media of varying SiOsb2/Alsb2Osb3 ratio were evaluated for sorption and destruction of TCE. This investigation led to the development of a Cr-ZSM-5 (SiOsb2/Alsb2Osb3=80,\\ {˜}0.5 wt% chromium) as an efficient S/C medium for TCE destruction. In the fourth investigation, deactivation experiments were carried out on four Cr-ZSM-5 catalysts. Under the conditions used, all the catalysts

  6. Influence of chlorine on methane oxidation.

    PubMed

    Chi, Yong; Wang, Bo; Yan, Jianhua; Ni, Mingjiang

    2009-01-01

    Experiments on CH4/Cl2/O2/N2 oxidation were conducted in an atmospheric pressure flow reactor to understand the influence of chlorine on hydrocarbon oxidation in hazardous waste incineration. The reaction temperature varied from 973 to 1273 K and the chlorine to hydrogen mole ratio (Cl/H) of the inlet mixture varied from 0 to 0.44. The species produced in the reaction were measured online with Fourier transform infrared spectroscopy (FT-IR). It was found that the destruction and removal efficiency of CH4 increased with Cl/H mole ratio. Increasing Cl/H favored COCl2 and CO formation and inhibited the CO oxidation process. As Cl/H approached 0.44, the concentrations of CH2Cl2 and CH3Cl first increased, and then declined. Reaction temperature greatly affected the reaction system. Increasing temperatures raised the destruction removal efficiency of CH4 and decreased the concentrations of CH3Cl and CH2Cl2. With a certain ratio of Cl/H, the concentrations of CO and COCl2 first increased and then declined. The CO and COCl2 concentration peak was observed around 1100 K and 1023 K, respectively. When the reaction temperature exceeded 1273 K, carbon in CH4 was mostly converted to CO2. It could be concluded that the presence of chlorine enhanced the destruction of CH4, but resulted in the more toxic incomplete combustion products emission such as COCl2 when the reaction temperature was not high enough. PMID:19999983

  7. 40 CFR 704.45 - Chlorinated terphenyl.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... means the percent by weight of chlorine for each isomer (ortho, meta, and para). (3) Isomeric ratio... chlorinated terphenyl. (4) A description of the isomeric ratio and extent of chlorination of the...

  8. A comparison of chlorinated organic material produced by chlorine and chlorine dioxide bleaching

    SciTech Connect

    McKaque, A.B.; Reeve, D.W.

    1995-12-31

    Chlorine and chlorine dioxide react differently with pulp during bleaching and produce different types of organic by-products. The main differences are the large reduction in the amount of AOX (adsorbable organic halogen) in the effluent and EOX (extractable organic halogen) in the pulp. This talk reviews the differences in the amounts and types of chlorinated organic by-products produced by the two different bleaching agents.

  9. REACTION OF ACTIVATED CARBON WITH AQUEOUS CHLORINE AND CHLORINE DIOXIDE

    EPA Science Inventory

    The objective of this research was to determine whether aqueous chlorine and chlorine dioxide react with activated carbon, or with compounds adsorbed on activated carbon, to produce compounds that would not form in the absence of activated carbon. The experimental conditions were...

  10. Assessment of pesticide residues in two arable soils from the semi-arid and subtropical regions of China.

    PubMed

    Wang, Ligang; Zhao, Zhenhua; Jiang, Xin; Wu, Jinshui; Martens, Dieter

    2005-10-01

    The residues of 31 chlorinated hydrocarbons (CHCs), 25 chlorophenols (CPs), 30 organophosphorus (OP) and pyrethroid (PRT) in two arable soils from the semi-arid and subtropical regions of China were assessed. Data obtained indicate that the main compounds of CHC pesticide residues in the semi-arid soil were 4,4'-DDE (25.3 ng/g) and beta-HCH (14.1 ng/g), which totally accounted to about 90% of total CHC residues detected. The total content of CHC residues detected in the subtropical soil was only 3.1 ng/g, of which approximately 50% was beta-HCH. However, the total content of CP residues in both of the soils was about 11 ng/g. In the semi-arid soil, only parathion-methyl amongst the 30 compounds of OP and PRT residues was detected (32.5 ng/g), whilst malathion and parathion-methyl (8.7 and 17.7 ng/g, respectively) detected in the subtropical soil. Based on these results, it was suggested the environmental risk of pesticide residues ranked in an order as CHCs (mainly as 4,4'-DDE, beta-HCH) > OP (parathion-methyl) > CPs for the semi-arid soil, and as OPs (parathion-methyl and malathion) > CPs > CHCs (beta-HCH) for the subtropical soil. PMID:16240205

  11. Tropospheric budget of reactive chlorine

    NASA Astrophysics Data System (ADS)

    Graedel, T. E.; Keene, W. C.

    1995-03-01

    Reactive chlorine in the lower atmosphere (as distinguished from chlorofluorocarbon-derived chlorine in the stratosphere) is important to considerations of precipitation acidity, corrosion, foliar damage, and chemistry of the marine boundary layer. Many of the chlorine-containing gases are difficult to measure, and natural sources appear to dominate anthropogenic sources for some chemical species. As a consequence, no satisfactory budget for reactive chlorine in the lower atmosphere is available. We have reviewed information on sources; source strengths; measurements in gas, aqueous, and aerosol phases; and chemical processes and from those data derive global budgets for nine reactive chlorine species and for reactive chlorine as a whole. The typical background abundance of reactive chlorine in the lower tropospheric is about 1.5 ppbv. The nine species, CH3 Cl, CH3 CCl3, HCl, CHClF2, Cl2* (thought to be HOCl and/or Cl2), CCl2 = CCl2, CH2 Cl2 , COCl2 , and CHCl3, each contribute at least a few percent to that total. The tropospheric reactive chlorine burden of approximately 8.3 Tg Cl is dominated by CH3 Cl (≈45 %) and CH3 CCl3 (≈25 %) and appears to be increasing by several percent per year. By far the most vigorous chlorine cycling appears to occur among seasalt aerosol, HCl, and Cl2*. The principal sources of reactive chlorine are volatilization from seasalt (enhanced by anthropogenically generated reactants), marine algae, volcanoes, and coal combustion (natural sources being thus quite important to the budget). It is anticipated that the concentrations of tropospheric reactive chlorine will continue to increase in the next several decades, particularly near urban areas in the rapidly developing countries.

  12. Chlorine adsorption on Au(111): chlorine overlayer or surface chloride?

    PubMed

    Gao, Weiwei; Baker, Thomas A; Zhou, Ling; Pinnaduwage, Dilini S; Kaxiras, Efthimios; Friend, Cynthia M

    2008-03-19

    We report the first scanning tunneling microscope (STM) investigation, combined with density functional theory calculations, to resolve controversy regarding the bonding and structure of chlorine adsorbed on Au(111). STM experiments are carried out at 120 K to overcome instability caused by mobile species upon chlorine adsorption at room temperature. Chlorine adsorption initially lifts the herringbone reconstruction. At low coverages (<0.33 ML), chlorine binds to the top of Au(111)-(1 x 1) surface and leads to formation of an overlayer with (square root(3) x square root(3))R30 degree structure at 0.33 ML. At higher coverages, packing chlorine into an overlayer structure is no longer favored. Gold atoms incorporate into a complex superlattice of a Au-Cl surface compound. PMID:18290645

  13. Highly chlorinated unintentionally produced persistent organic pollutants generated during the methanol-based production of chlorinated methanes: A case study in China.

    PubMed

    Zhang, Lifei; Yang, Wenlong; Zhang, Linli; Li, Xiaoxiu

    2015-08-01

    The formation of unintentionally produced persistent organic pollutants (POPs) may occur during various chlorination processes. In this study, emissions of unintentionally produced POPs during the methanol-based production of chlorinated methanes were investigated. High concentrations of highly chlorinated compounds such as decachlorobiphenyl, octachloronaphthalene, octachlorostyrene, hexachlorobutadiene, hexachlorocyclopentadiene, hexachlorobenzene, and pentachlorobenzene were found in the carbon tetrachloride byproduct of the methanol-based production of chlorinated methanes. The total emission amounts of hexachlorocyclopentadiene, hexachlorobutadiene, polychlorinated benzenes, polychlorinated naphthalenes, octachlorostyrene, and polychlorinated biphenyls released during the production of chlorinated methanes in China in 2010 were estimated to be 10080, 7350, 5210, 427, 212, and 167 kg, respectively. Moreover, polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) were formed unintentionally during chlorinated methanes production, the emission factor for PCDDs/DFs was 364 μg toxic equivalency quotient (TEQ) t(-1) product for residues, which should be added into the UNEP toolkit for updating. It was worth noting that a high overall toxic equivalency quotient from polychlorinated naphthalenes and PCDDs/DFs was generated from the chlorinated methanes production in China in 2010. The values reached 563 and 32.8 g TEQ, respectively. The results of the study indicate that more research and improved management systems are needed to ensure that the methanol-based production of chlorinated methanes can be achieved safely. PMID:25777670

  14. Chlorine analysis by diode laser atomic absorption spectrometry.

    PubMed

    Koch, J; Zybin, A; Niemax, K

    2000-04-01

    The general characteristics of Diode Laser Absorption Spectrometry (DLAAS) in low pressure plasmas particularly 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 expected proportions were found to be insignificant, implying the possibility of internal standardization relative to the response of a reference sample. PMID:12953476

  15. 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.

    PubMed

    Sapozhnikova, Yelena; Lehotay, Steven J

    2013-01-01

    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 1h/analyst, and LP-GC/MS-MS analysis provided fast separation of multiple analytes within 9min 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 0.1-0.5ng g(-1) for PCBs, 0.5-10ng g(-1) for PBDEs, 0.5-5ng g(-1) for select pesticides and PAHs and 1-10ng g(-1) for flame retardants. The developed method was successfully applied for analysis of catfish samples from the market. PMID:23245899

  16. Apparatus for hydrocarbon extraction

    DOEpatents

    Bohnert, George W.; Verhulst, Galen G.

    2013-03-19

    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.

  17. PERSISTENCE OF CHLORINATED HYDROCARBON CONTAMINATION IN A CALIFORNIA MARINE ECOSYSTEM

    EPA Science Inventory

    Despite major reductions in the dominant DDT and polychlorinated biphenyls (PCB) input off Los Angeles (California, USA) in the early 1970s, the levels of these pollutants decreased only slightly from 1972 to 1975 both in surficial bottom sediments and in a flatfish bioindicator ...

  18. Corrosion of aluminum alloys by chlorinated hydrocarbon/methanol mixtures

    NASA Technical Reports Server (NTRS)

    De Forest, W. S.

    1967-01-01

    Laboratory investigations show that water-free mixtures of Freon MF /trichlorofluoromethane/ and methanol vigorously attack aluminum alloys which contain significant amounts of copper. Freon MF alone did not attack the aluminum alloys at room temperature. Pure methanol had only a slight corrosive effect on the alloy.

  19. Biodegradation of chlorinated hydrocarbons in a vapor phase reactor

    SciTech Connect

    Ensley, B.D.

    1992-01-01

    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 [mu]g/L (60ppmv) and 3000 [mu]g/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.

  20. Chlorinated hydrocarbons in the young of Lake Michigan coho salmon

    USGS Publications Warehouse

    Willford, W.A.; Sills, J.B.; Whealdon, E.W.

    1969-01-01

    Three thousand eyed coho salmon (Oncorhynchus kisutch) eggs from Lake Michigan stock were sent by the Department of Natural Resources to the Fish Control Laboratory, La Crosse, Wis., on January 15, 1969, for use in evaluating candidate fish-cnotrol chemicals.

  1. INVESTIGATION OF THE METABOLISM OF CHLORINATED HYDROCARBONS IN SUBHUMAN SPECIES

    EPA Science Inventory

    The purpose of this research program was to provide metabolic data on four rather common drinking water contaminants. The compounds were 1,2,4-trichlorobenzene (TCB), bromodichloromethane (BDC), bis(2-chloroisopropyl) ether (BCIE) and bis(2-chloroethyl) ether (BCEE). The compound...

  2. PERMEABLE REACTIVE WALL REMEDIATION OF CHLORINATED HYDROCARBONS IN GROUNDWATER

    EPA Science Inventory

    A pilot-scale permeable reactive barrier was installed at Moffett Field in April 1996 and its performance was monitored over the following 16 months on a quarterly basis. The details of this study are described in a technology evaluation report (Battelle, 1998). This document pro...

  3. USING TREES TO REMEDIATE GROUNDWATERS CONTAMINATED WITH CHLORINATED HYDROCARBONS

    EPA Science Inventory

    Phytoremediation has emerged as a treatment alternative that combines the low cost of intrinsic remediation with the more active and adaptable characteristics of conventional remediation. Our lab has shown that fast-growing and deep-rooted hybrid poplar take up and transpire tric...

  4. MICROEMULSION FORMATION WITH CHLORINATED HYDROCARBONS OF DIFFERING POLARITY

    EPA Science Inventory

    Winsor Type I (o/w), Type II (w/o), and Type III (middle phase) microemulsions have been produced for water and CC14, water and trichloroethylene (TCE), and water and 1,2-dichlorobenzene (DCB) with anionic surfactants and appropriate electrolytes. ttempts at producing classical p...

  5. Biological Chlorine Cycling in Arctic Peat Soils

    NASA Astrophysics Data System (ADS)

    Zlamal, J. E.; Raab, T. K.; Lipson, D.

    2014-12-01

    Soils of the Arctic tundra near Barrow, Alaska are waterlogged and anoxic throughout most of the profile due to underlying permafrost. Microbial communities in these soils are adapted for the dominant anaerobic conditions and are capable of a surprising diversity of metabolic pathways. Anaerobic respiration in this environment warrants further study, particularly in the realm of electron cycling involving chlorine, which preliminary data suggest may play an important role in arctic anaerobic soil respiration. For decades, Cl was rarely studied outside of the context of solvent-contaminated sites due to the widely held belief that it is an inert element. However, Cl has increasingly become recognized as a metabolic player in microbial communities and soil cycling processes. Organic chlorinated compounds (Clorg) can be made by various organisms and used metabolically by others, such as serving as electron acceptors for microbes performing organohalide respiration. Sequencing our arctic soil samples has uncovered multiple genera of microorganisms capable of participating in many Cl-cycling processes including organohalide respiration, chlorinated hydrocarbon degradation, and perchlorate reduction. Metagenomic analysis of these soils has revealed genes for key enzymes of Cl-related metabolic processes such as dehalogenases and haloperoxidases, and close matches to genomes of known organohalide respiring microorganisms from the Dehalococcoides, Dechloromonas, Carboxydothermus, and Anaeromyxobacter genera. A TOX-100 Chlorine Analyzer was used to quantify total Cl in arctic soils, and these data were examined further to separate levels of inorganic Cl compounds and Clorg. Levels of Clorg increased with soil organic matter content, although total Cl levels lack this trend. X-ray Absorption Near Edge Structure (XANES) was used to provide information on the structure of Clorg in arctic soils, showing great diversity with Cl bound to both aromatic and alkyl groups

  6. Perspectives on the Meaning of Detectable Distribution System Residual and Implications for N. Fowleri Control

    EPA Science Inventory

    The objectives of this presentation are to: review history of distribution system chlorination regulations, raise awareness on the meaning of detectable residual as it relates to chloramines, and perhaps renew dialogue on the discussion of minimum disinfectant residuals.

  7. Stimulation of 2-methylisoborneol (MIB) production by actinomycetes after cyclic chlorination in drinking water distribution systems.

    PubMed

    Abbaszadegan, Morteza; Yi, Min; Alum, Absar

    2015-01-01

    The impact of fluctuation in chlorine residual on actinomycetes and the production of 2-methylisoborneol (MIB) were studied in cast-iron and PVC model distribution systems. Actinomycetes were spiked in each system and continued operation for a 12-day non-chlorine experiment, resulting in no changes in actinomycetes and MIB concentrations. Three cyclic chlorination events were performed and chlorine residuals were maintained as follows: 1.0 mg L(-1) for 24 h, 0 mg L(-1) for 48 h, 0.5 mg L(-1) for 48 h, 0 mg L(-1) for 48 h and 2 mg L(-1) for 24 h. After each chlorination event, 2 -3 log decrease in actinomycetes was noted in both systems. However, within 48 h at 0 mg L(-1) chlorine, the actinomycetes recovered to the pre-chlorination levels. On the contrary, MIB concentration in both systems remained un-impacted after the first cycle and increased by fourfold (< 5 to > 20 mg L(-1)) after the second cycle, which lasted through the third cycle despite the fact that actinomycetes numbers fluctuated 2-3 logs during this time period. For obtaining biofilm samples from field, water meters were collected from municipality drinking water distribution systems located in central Arizona. The actinomycetes concentration in asbestos cement pipe and cast iron pipe averaged 3.1 × 10(3) and 1.9 × 10(4) CFU cm(-2), respectively. The study shows that production of MIB is associated with changes in chlorine residual in the systems. This is the first report of cyclic chlorine shock as a stimulus for MIB production by actinomycetes in drinking water distribution system's ecology. PMID:25723062

  8. 46 CFR 151.50-31 - Chlorine.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Chlorine. 151.50-31 Section 151.50-31 Shipping COAST... LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-31 Chlorine. (a) Chlorine barges. Subparts 98.03 and 98.20 of Part 98 of this chapter have been revoked. However, chlorine barges that...

  9. 46 CFR 151.50-31 - Chlorine.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Chlorine. 151.50-31 Section 151.50-31 Shipping COAST... LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-31 Chlorine. (a) Chlorine barges. Subparts 98.03 and 98.20 of Part 98 of this chapter have been revoked. However, chlorine barges that...

  10. 46 CFR 151.50-31 - Chlorine.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Chlorine. 151.50-31 Section 151.50-31 Shipping COAST... LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-31 Chlorine. (a) Chlorine barges. Subparts 98.03 and 98.20 of Part 98 of this chapter have been revoked. However, chlorine barges that...

  11. 46 CFR 151.50-31 - Chlorine.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Chlorine. 151.50-31 Section 151.50-31 Shipping COAST... LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-31 Chlorine. (a) Chlorine barges. Subparts 98.03 and 98.20 of Part 98 of this chapter have been revoked. However, chlorine barges that...

  12. Zebra mussel mortality with chlorine

    SciTech Connect

    Van Benschoten, J.E.; Jensen, J.N.; Harrington, D.; DeGirolamo, D.J.

    1995-05-01

    The rate of mortality of the zebra mussel in response to chlorine is described by a kinetic model that combines a statistical characterization of mussel mortality with a disinfection-type modeling approach. Parameter estimates were made with nine sets of data from experiments conducted in Niagara River water. From the kinetic model, an operational diagram was constructed that describes the time to 95% mortality as a function of chlorine concentration and temperature. Either the model or the diagram can be used to assist utilities in planning chlorination treatments for controlling zebra mussels.

  13. CHLORINE INACTIVATION OF BACILLUS ENDOSPORES

    EPA Science Inventory

    The possibility of a bioterrorism event resulting in the release of Bacillus anthracis endospores into a drinking water distribution system necessitates research into means by which these endospores can be inactivated. This study was designed to determine the chlorine resistance...

  14. CHLORINATION OF AQUATIC HUMIC SUBSTANCES

    EPA Science Inventory

    This research program was initiated with the overall objective of increasing our understanding of the chemical structures of aquatic humic material and their behavior during chemical oxidation in particular with chlorine. Experimental methods were devised for the isolation of hum...

  15. Influence of drinking water treatments on chlorine dioxide consumption and chlorite/chlorate formation.

    PubMed

    Sorlini, Sabrina; Gialdini, Francesca; Biasibetti, Michela; Collivignarelli, Carlo

    2014-05-01

    Disinfection is the last treatment stage of a Drinking Water Treatment Plant (DWTP) and is carried out to maintain a residual concentration of disinfectant in the water distribution system. Chlorine dioxide (ClO2) is a widely used chemical employed for this purpose. The aim of this work was to evaluate the influence of several treatments on chlorine dioxide consumption and on chlorite and chlorate formation in the final oxidation/disinfection stage. A number of tests was performed at laboratory scale employing water samples collected from the DWTP of Cremona (Italy). The following processes were studied: oxidation with potassium permanganate, chlorine dioxide and sodium hypochlorite, coagulation/flocculation with ferric chloride and aluminum sulfate, filtration and adsorption onto activated carbon. The results showed that the chlorine dioxide demand is high if sodium hypochlorite or potassium permanganate are employed in pre-oxidation. On the other hand, chlorine dioxide leads to the highest production of chlorite and chlorate. The coagulation/flocculation process after pre-oxidation shows that chlorine dioxide demand decreases if potassium permanganate is employed as an oxidant, both with ferric chloride and aluminum sulfate. Therefore, the combination of these processes leads to a lower production of chlorite and chlorate. Aluminum sulfate is preferable in terms of the chlorine dioxide demand reduction and minimization of the chlorite and chlorate formation. Activated carbon is the most effective solution as it reduced the chlorine dioxide consumption by about 50% and the DBP formation by about 20-40%. PMID:24534637

  16. A carbon nanotube based resettable sensor for measuring free chlorine in drinking water

    NASA Astrophysics Data System (ADS)

    Hsu, Leo H. H.; Hoque, Enamul; Kruse, Peter; Ravi Selvaganapathy, P.

    2015-02-01

    Free chlorine from dissolved chlorine gas is widely used as a disinfectant for drinking water. The residual chlorine concentration has to be continuously monitored and accurately controlled in a certain range around 0.5-2 mg/l to ensure drinking water safety and quality. However, simple, reliable, and reagent free monitoring devices are currently not available. Here, we present a free chlorine sensor that uses oxidation of a phenyl-capped aniline tetramer (PCAT) to dope single wall carbon nanotubes (SWCNTs) and to change their resistance. The oxidation of PCAT by chlorine switches the PCAT-SWCNT system into a low resistance (p-doped) state which can be detected by probing it with a small voltage. The change in resistance is found to be proportional to the log-scale concentration of the free chlorine in the sample. The p-doping of the PCAT-SWCNT film then can be electrochemically reversed by polarizing it cathodically. This sensor not only shows good sensing response in the whole concentration range of free chlorine in drinking water but is also able to be electrochemically reset back many times without the use of any reagents. This simple sensor is ideally suited for measuring free chlorine in drinking water continuously.

  17. A carbon nanotube based resettable sensor for measuring free chlorine in drinking water

    SciTech Connect

    Hsu, Leo H. H.; Hoque, Enamul; Kruse, Peter; Ravi Selvaganapathy, P.

    2015-02-09

    Free chlorine from dissolved chlorine gas is widely used as a disinfectant for drinking water. The residual chlorine concentration has to be continuously monitored and accurately controlled in a certain range around 0.5–2 mg/l to ensure drinking water safety and quality. However, simple, reliable, and reagent free monitoring devices are currently not available. Here, we present a free chlorine sensor that uses oxidation of a phenyl-capped aniline tetramer (PCAT) to dope single wall carbon nanotubes (SWCNTs) and to change their resistance. The oxidation of PCAT by chlorine switches the PCAT-SWCNT system into a low resistance (p-doped) state which can be detected by probing it with a small voltage. The change in resistance is found to be proportional to the log-scale concentration of the free chlorine in the sample. The p-doping of the PCAT-SWCNT film then can be electrochemically reversed by polarizing it cathodically. This sensor not only shows good sensing response in the whole concentration range of free chlorine in drinking water but is also able to be electrochemically reset back many times without the use of any reagents. This simple sensor is ideally suited for measuring free chlorine in drinking water continuously.

  18. IDENTIFICATION OF NEW DRINKING WATER DISINFECTION BY-PRODUCTS FROM OZONE, CHLORINE DIOXIDE, CHLORAMINE, AND CHLORINE

    EPA Science Inventory

    Due to concern over the potential adverse health effects of trihalomethanes (THMs) and other chlorinated by-products in chlorinated drinking water, alternative disinfection methods are being explored. Ozone, chlorine dioxide, and chloramine are currently popular alternatives to ...

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

    EPA Science Inventory

    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...

  20. Transformation of iopamidol during chlorination.

    PubMed

    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). PMID:25325766

  1. Organo-Chlorinated Thin Films Deposited by Atmospheric Pressure Plasma-Enhanced Chemical Vapor Deposition for Adhesion Enhancement between Rubber and Zinc-Plated Steel Monofilaments.

    PubMed

    Vandenabeele, Cédric; Bulou, Simon; Maurau, Rémy; Siffer, Frederic; Belmonte, Thierry; Choquet, Patrick

    2015-07-01

    A continuous-flow plasma process working at atmospheric pressure is developed to enhance the adhesion between a rubber compound and a zinc-plated steel monofilament, with the long-term objective to find a potential alternative to the electrolytic brass plating process, which is currently used in tire industry. For this purpose, a highly efficient tubular dielectric barrier discharge reactor is built to allow the continuous treatment of "endless" cylindrical substrates. The best treatment conditions found regarding adhesion are Ar/O2 plasma pretreatment, followed by the deposition from dichloromethane of a 75 nm-thick organo-chlorinated plasma polymerized thin film. Ar/O2 pretreatment allows the removal of organic residues, coming from drawing lubricants, and induces external growth of zinc oxide. The plasma layer has to be preferably deposited at low power to conserve sufficient hydrocarbon moieties. Surface analyses reveal the complex chemical mechanism behind the establishment of strong adhesion levels, more than five times higher after the plasma treatment. During the vulcanization step, superficial ZnO reacts with the chlorinated species of the thin film and is converted into porous and granular bump-shaped ZnwOxHyClz nanostructures. Together, rubber additives diffuse through the plasma layer and lead to the formation of zinc sulfide on the substrate surface. Hence, two distinct interfaces, rubber/thin film and thin film/substrate, are established. On the basis of these observations, hypotheses explaining the high bonding strength results are formulated. PMID:26069994

  2. Hydrocarbon residues in tissues of sea otters (`enhydra lutris`) collected following the Exxon Valdez oil spill. Marine mammal study 6-16. Exxon Valdez oil spill state/federal natural resource damage assessment. Final report

    SciTech Connect

    Ballachey, B.E.; Kloecker, K.A.

    1997-04-01

    Ten moderately to heavily oiled sea otters were collected in Prince William Sound during the Exxon Valdez oil spill and up to seven tissues from each were analyzed for hydrocarbons. Aliphatic and aromatic hydrocarbons were detected in all tissues. Concentrations of aromatic hydrocarbons in fat samples were an order of magnitude higher than in other tissues. The patterns of distribution of these hydrocarbons suggested crude oil as the source of contamination. However, there was variation among oiled otters in the concentrations of individual hydrocarbons, which may be due to differing proximate causes of mortality and varying lengths of time and sea otters survived following oil exposure. The concentrations of both aliphatic and aromatic hydrocarbons in the tissues of the ten oiled sea otters generally were higher than in tissues from 7 sea otters with no external oiling that were collected from prince William Sound in 1989 and 1990, or from 12 sea otters collected from an area in southeast Alaska which had not experienced an oil spill.

  3. Application of Chlorine-Assisted Chemical Vapor Deposition of Diamond at Low Temperatures

    NASA Technical Reports Server (NTRS)

    Pan, Chenyu; Altemir, David A.; Margrave, John L.; Hauge, Robert H.

    1994-01-01

    Low temperature deposition of diamond has been achieved by a chlorine-assisted diamond chemical vapor deposition (CA-CVD) process. This method begins with the thermal dissociation of molecular chlorine into atomic chlorine in a resistively heated graphite furnace at temperatures between 1300 and 1500 deg. C. The atomic chlorine, upon mixing, subsequently reacts with molecular hydrogen and hydrocarbons. The rapid exchange reactions between the atomic chlorine, molecular hydrogen, and hydrocarbons give rise to the atomic hydrogen and carbon precursors required for diamond deposition. Homoepitaxial diamond growth on diamond substrates has been studied over the substrate temperature range of 100-950 C. It was found that the diamond growth rates are approximately 0.2 microns/hr in the temperature range between 102 and 300 C and that the growth rates do not decrease significantly with a decrease in substrate temperature. This is unique because the traditional diamond deposition using H2/CH4 systems usually disappears at substrate temperatures below approx. 500 deg. C. This opens up a possible route to the deposition of diamond on low-melting point materials such as aluminum and its alloys.

  4. Cleaning without chlorinated solvents

    SciTech Connect

    Thompson, L.M.; Simandl, R.F.

    1994-12-31

    Because of health and environmental concerns, many regulations have been passed in recent years regarding the use of chlorinated solvents. The Oak Ridge Y-12 Plant has had an active program to find alternatives for these solvents used in cleaning applications for the past 7 years. During this time frame, the quantity of solvents purchased has been reduced by 92%. The program has been a twofold effort. Vapor degreasers used in batch cleaning-operations have been replaced by ultrasonic cleaning with aqueous detergent, and other organic solvents have been identified for use in hand-wiping or specialty operations. In order to qualify these alternatives for use, experimentation was conducted on cleaning ability as well as effects on subsequent operations such as welding, painting and bonding. Cleaning ability was determined using techniques such as X-ray photoelectron spectroscopy (XPS) and Fourier Transform Infrared Spectroscopy (FTIR) which are capable of examining monolayer levels of contamination on a surface. Solvents have been identified for removal of rust preventative oils, lapping oils, machining coolants, lubricants, greases, and mold releases. Solvents have also been evaluated for cleaning urethane foam spray guns, swelling of urethanes and swelling of epoxies.

  5. Cleaning without chlorinated solvents

    NASA Technical Reports Server (NTRS)

    Thompson, L. M.; Simandl, R. F.

    1995-01-01

    Because of health and environmental concerns, many regulations have been passed in recent years regarding the use of chlorinated solvents. The Oak Ridge Y-12 Plant has had an active program to find alternatives for these solvents used in cleaning applications for the past 7 years. During this time frame, the quantity of solvents purchased has been reduced by 92 percent. The program has been a twofold effort. Vapor degreasers used in batch cleaning operations have been replaced by ultrasonic cleaning with aqueous detergent, and other organic solvents have been identified for use in hand-wiping or specialty operations. In order to qualify these alternatives for use, experimentation was conducted on cleaning ability as well as effects on subsequent operations such as welding, painting, and bonding. Cleaning ability was determined using techniques such as x-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) which are capable of examining monolayer levels of contamination on a surface. Solvents have been identified for removal of rust preventative oils, lapping oils, machining coolants, lubricants, greases, and mold releases. Solvents have also been evaluated for cleaning urethane foam spray guns, swelling of urethanes, and swelling of epoxies.

  6. Stable isotopic investigations of in-situ bioremediation of chlorinated organic solvents. 1998 annual progress report

    SciTech Connect

    Sturchio, N.C.

    1998-06-01

    'Contamination of soils and groundwaters with chlorinated aliphatic hydrocarbons (CAHs) is one of the most serious environmental problems in the DOE system and in the nation at large. These compounds are designated as priority pollutants by the US Environmental Protection Agency (EPA) and are known or suspected to be carcinogenic or mutagenic in humans. These compounds are readily transported by groundwater and are not reduced to acceptable concentrations for human consumption by most municipal water supply treatments; thus the compounds represent a significant hazard to a large portion of the human population. In situ bioremediation is an emerging technology that shows great promise for mitigation of CAH contamination at many sites. One of the most severe limitations of in-situ bioremediation is the difficulty of proving when it is working at a given site. The concentrations of CAHs and their degradation products in plumes may be difficult to relate to the efficiency of the remediation process because of dilution effects, but this problem is mitigated to a large extent by measuring isotope ratios. If there is a significant isotopic fractionation between CAHs and derivative chlorine-bearing products, then the fraction of CAH that is dechlorinated can be inferred from the {sup 37}Cl/{sup 35}Cl and {sup 13}C/{sup 12}C isotope ratios of the residual CAH. It is important to point out that there is currently no published information available on the magnitude of chlorine and carbon isotopic fractionation associated with biological degradation of CAHs. The authors plan to help eliminate this important gap in the knowledge with the work being performed here. This work is relevant to EMSP goals because it will provide a new and cost-effective means of evaluating and monitoring the effectiveness of in-situ bioremediation. It will employ newly developed techniques to characterize isotopic fractionation (of chlorine and carbon) associated with biotic and abiotic degradation

  7. Upgrading heavy hydrocarbon oils using sodium hypochlorite

    SciTech Connect

    Rankel, L.A.

    1986-07-22

    A process is described for demetallizing a residual hydrocarbon fraction comprising: (a) contacting the hydrocarbon fraction with an aqueous solution of a hypochlorite salt; (b) separating the mixture into an aqueous phase and an oil phase; (c) contacting the oil phase with a deasphalting solvent and (d) obtaining by separation a product comprising a demetallized oil fraction suitable for use as a feedstock for catalytic processing.

  8. Persistence of pharmaceuticals and other organic compounds in chlorinated drinking water as a function of time

    USGS Publications Warehouse

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

    2007-01-01

    Ninety eight pharmaceuticals and other organic compounds (POOCs) that were amended to samples of chlorinated drinking-water were extracted and analyzed 1, 3, 6, 8, and 10 days after amendment to determine whether the total chlorine residual reacted with the amended POOCs in drinking water in a time frame similar to the residence time of drinking water in a water distribution system. Results indicated that if all 98 were present in the finished drinking water from a drinking-water treatment plant using free chlorine at 1.2??mg/L as the distribution system disinfectant residual, 52 POOCs would be present in the drinking water after 10??days at approximately the same concentration as in the newly finished drinking water. Concentrations of 16 POOCs would be reduced by 32% to 92%, and 22 POOCs would react completely with residual chlorine within 24??h. Thus, the presence of free chlorine residual is an effective means for transforming some POOCs during distribution. ?? 2006 Elsevier B.V. All rights reserved.

  9. Evaluation of the use of chlorine dioxide to control zebra mussels

    SciTech Connect

    Tsou, J.; Coyle, J.; Pallo, S.

    1995-06-01

    Chlorine dioxide was tested as a zebra mussel biocide at two steam electric generating stations in Illinois. The purpose of these studies was to determine the efficacy of chlorine dioxide in killing zebra mussels and to develop site specific treatment programs for the two utilities. The Electric Power Research Institute (EPRI) Zebra Mussel Consortium sponsored the testing of this recent use of chlorine dioxide. The raw water system at Central Illinois Public Service`s Meredosia Station, on the Illinois River, received two to four day applications of chlorine dioxide in April, July, and September 1994. The raw water system at Illinois Power Company`s Wood River Station, on the Mississippi River, received two to four day applications in July 1993, January, April, May, July, and September 1994. Chlorine dioxide was generated on-site and injected into the water intake structure, in front of or just behind the traveling screens, at both power stations. Both cooling and service water systems were treated at the facilities. Various water quality parameters, including residual chlorine in the discharge effluent, were measured during the studies. Residual chlorine was neutralized with sodium bisulfite prior to discharge at both plants. Bioboxes, containing healthy zebra mussels, were placed at various strategic locations throughout the power stations. Control bioboxes were also placed in the rivers, upstream of the chlorine dioxide injection locations. Results of the chlorine dioxide applications varied from 35 percent to 100 percent. These varied results appear to be related to seasonal water temperature differences, water quality, and/or plant design. Mortality differences were also noted in bioboxes which contained zebra mussels imported from Lake Erie and those which contained local mussels. These and other data are presented.

  10. Anaerobic biotransformation of chlorinated alkenes

    SciTech Connect

    Zhuang, P.

    1994-01-01

    Chlorinated alkenes are widely found in contaminated subsurface soil and groundwater. The highly chlorinated alkene (i.e., PCE) is not subject to aerobic biotransformation. The aim of this research was to explore the potential of using anaerobic processes (i.e., denitrification, sulfate-reduction and methanogenesis) for chlorinated alkenes biotransformation. Contaminated soil samples were used throughout this study. Soil microcosms simulating field anoxic conditions with various nutrients amendment, liquid microcosms as well as enrichment liquid cultures were developed to delineate the dechlorination process. The effect of biomass, chlorinated alkenes concentration and site specific conditions (e.g., temperature and pH) on the dechlorination and the primary metabolic process was investigated. The role of sorption and nutritional needs (i.e., electron donor) were also studied. A preliminary study revealed that denitrification was the least affected by low temperatures as compared to sulfate-reduction and methanogenesis. Although dechlorination took place under sequential denitrifying and methanogenic conditions and under sulfate-reducing conditions, further studies concluded that fermentative and methanogenic bacteria were responsible for the observed dechlorination. In most cases, dechlorination of PCE or TCE resulted in the accumulation of cDCE. However, a VC-producing culture was developed from the PCE-contaminated soil. In general, the dechlorination process could be enhanced by increasing electron donor and biomass concentration. At relatively low concentrations, the dechlorination rate was also increased with increasing chlorinated alkene concentration. Dechlorination even proceeded at high chlorinated alkene concentrations when methane production was inhibited. However, as the concentration of the chlorinated alkenes increased, severe toxicity eventually halted the dechlorination process.

  11. Biological Instability in a Chlorinated Drinking Water Distribution Network

    PubMed Central

    Nescerecka, Alina; Rubulis, Janis; Vital, Marius; Juhna, Talis; Hammes, Frederik

    2014-01-01

    The purpose of a drinking water distribution system is to deliver drinking water to the consumer, preferably with the same quality as when it left the treatment plant. In this context, the maintenance of good microbiological quality is often referred to as biological stability, and the addition of sufficient chlorine residuals is regarded as one way to achieve this. The full-scale drinking water distribution system of Riga (Latvia) was investigated with respect to biological stability in chlorinated drinking water. Flow cytometric (FCM) intact cell concentrations, intracellular adenosine tri-phosphate (ATP), heterotrophic plate counts and residual chlorine measurements were performed to evaluate the drinking water quality and stability at 49 sampling points throughout the distribution network. Cell viability methods were compared and the importance of extracellular ATP measurements was examined as well. FCM intact cell concentrations varied from 5×103 cells mL−1 to 4.66×105 cells mL−1 in the network. While this parameter did not exceed 2.1×104 cells mL−1 in the effluent from any water treatment plant, 50% of all the network samples contained more than 1.06×105 cells mL−1. This indisputably demonstrates biological instability in this particular drinking water distribution system, which was ascribed to a loss of disinfectant residuals and concomitant bacterial growth. The study highlights the potential of using cultivation-independent methods for the assessment of chlorinated water samples. In addition, it underlines the complexity of full-scale drinking water distribution systems, and the resulting challenges to establish the causes of biological instability. PMID:24796923

  12. Transformation pathways and acute toxicity variation of 4-hydroxyl benzophenone in chlorination disinfection process.

    PubMed

    Liu, Wei; Wei, Dongbin; Liu, Qi; Du, Yuguo

    2016-07-01

    Benzophenones compounds (BPs) are widely used as UV filters, and have been frequently found in multiple environmental matrices. The residual of BPs in water would cause potential threats on ecological safety and human health. Chlorination disinfection is necessary in water treatment process, in which many chemicals remained in water would react with disinfectant chlorine and form toxic by-products. By using ultra performance liquid phase chromatography quadrupole time of flight mass spectrometer (UPLC-QTOF-MS), nuclear magnetic resonance (NMR), the transformation of 4-hydroxyl benezophenone (4HB) with free available chlorine (FAC) was characterized. Eight major products were detected and seven of them were identified. Transformation pathways of 4HB under acid, neutral, and alkaline conditions were proposed respectively. The transformation mechanisms involved electrophilic chlorine substitution of 4HB, Baeyer-Villiger oxidation of ketones, hydrolysis of esters and oxidative breakage of benzene ring. The orthogonal experiments of pH and dosages of disinfectant chlorine were conducted. The results suggested that pH conditions determined the occurrence of reaction types, and the dosages of disinfectant chlorine affected the extent of reactions. Photobacterium assay demonstrated that acute toxicity had significant increase after chlorination disinfection of 4HB. It was proved that 3,5-dichloro-4HB, one of the major transformation products, was responsible for the increasing acute toxicity after chlorination. It is notable that, 4HB at low level in real ambient water matrices could be transformed during simulated chlorination disinfection practice. Especially, two major products 3-chloro-4HB and 3,5-dichloro-4HB were detected out, implying the potential ecological risk after chlorination disinfection of 4HB. PMID:27085063

  13. Zebra mussel control using periodic chlorine dioxide treatments. Final report

    SciTech Connect

    Mussalli, Y.G.; Martin, P.D.

    1995-11-01

    Chlorine dioxide was injected into the water intakes at two power plants in Illinois and one in Indiana in an effort to eradicate the existing population of zebra mussels and mitigate further settlement in station river water cooling systems. Results of the treatments at Illinois Power Company`s Wood River Station on the Mississippi River, Central Illinois Public Service`s Meredosia Station on the Illinois River, and SI Energy`s Gallagher Station on the Ohio River are reported. Treatments were performed on a turnkey basis, with three treatments performed at Meredosia Station in 1994, six treatments performed at Wood River Station between July 1993 and September 1994, and 2 treatments performed at Gallagher Station in 1994. For each treatment, a contractor installed and operated a portable chlorine dioxide generator, monitored water quality and oxidant levels, and provided and monitored bioboxes containing test mussels. Results of the treatments were very favorable, indicating a good potential for periodic treatments with chlorine dioxide to control zebra mussel infestations in the raw water systems of power plants and other industrial facilities. Some difficulties with the chlorine dioxide generation system and cold temperature effects reduced the treatment effectiveness, particularly the second treatment at Gallagher Station. Average induced mortalities ranged from 70 to 100% at Wood River, 87 to 92% at Meredosia, and 30 to 100% at Gallagher for native mussels. Dechlorination successfully kept total oxidant residual levels at or below 0.05 ppM during all treatments at all stations.

  14. Products from laboratory chlorination of fly ash from a municipal incinerator

    SciTech Connect

    Eiceman, G.A.; Rghei, H.O.

    1982-01-01

    Fly ash samples from a municipal incinerator were treated at 200 and 300 /sup 0/C with chlorine gas for 1 h. Changes in composition of organic compounds in the samples were determined by using GC and GC/MS analysis of benzene extracts. Chlorination of fly ash produced a series of highly chlorinated aromatic hydrocarbons including hexachlorobenzene, decachlorobiphenyl, and nonachlorobiphenyl. Tentative identifications are also listed for other compounds with the following proposed molecular formulas: C/sub 7/HOCl/sub 5/, C/sub 6/H/sub 3/O/sub 2/Cl/sub 3/, C/sub 8/Cl/sub 8/, and C/sub 12/H/sub 4/O/sub 3/Cl/sub 6/ (or C/sub 13/H/sub 8/O/sub 2/Cl/sub 6/). Production of some of these compounds is dependent upon chlorination of benzene-soluble-nonvolatile precursor which was present naturally in this fly ash. These results show that fly ash from municipal incinerators may undergo gas phase-particulate reactions under conditions of high temperature with a source of chlorine and that such reactions lead to the production of chlorinated organic compounds at trace concentration levels.

  15. PPCP degradation by UV/chlorine treatment and its impact on DBP formation potential in real waters.

    PubMed

    Yang, Xin; Sun, Jianliang; Fu, Wenjie; Shang, Chii; Li, Yin; Chen, Yiwei; Gan, Wenhui; Fang, Jingyun

    2016-07-01

    The ultraviolet/chlorine (UV/chlorine) water purification process was evaluated for its ability to degrade the residues of pharmaceuticals and personal care products (PPCPs) commonly found in drinking water sources. The disinfection byproducts (DBPs) formed after post-chlorination were documented. The performance of the UV/chlorine process was compared with that of the UV/hydrogen peroxide (UV/H2O2) process in treating three types of sand-filtered natural water. Except caffeine and carbamazepine residues, the UV/chlorine process was found to be 59-99% effective for feed water with a high level of dissolved organic carbon and alkalinity, and 27-92% effective for water with a high ammonia content. Both chlorine radicals and hydroxyl radicals were found to contribute to the observed PPCP degradation. The removal efficiencies of chlorine- and UV-resistant PPCPs such as carbamazepine and caffeine were 2-3 times greater than in the UV/H2O2 process in waters not enriched with ammonia. UV/chlorine treatment slightly enhanced the formation chloral hydrate (CH), haloketone (HK) and trichloronitromethane (TCNM). It reduced haloacetonitrile (HAN) formation during the post-chlorination in comparison with the UV/H2O2 process. In waters with high concentrations of ammonia, the UV/chlorine process was only 5-7% more effective than the UV/H2O2 process, and it formed slightly more THMs, HKs and TCNM along with reduced formation of CH and HAN. The UV/chlorine process is thus recommended as a good alternative to UV/H2O2 treatment for its superior PPCP removal without significantly enhancing DBP formation. PMID:27110887

  16. SPME-GC-EC of chlorinated paraffins in water

    SciTech Connect

    Webster, G.R.B.; Sarna, L.P.; Thomas, D.A.

    1995-12-31

    Contamination of aquatic ecosystems with chlorinated organic contaminants is an increasing toxicological problem. Chlorinated paraffins (CPs) are a class of compounds which are used as fire retardants in paints and as high pressure lubricants and are classified as Priority Toxic Substances under the Canadian Environmental Protection Act (CEPA). As the largest group of high molecular weight chlorinated hydrocarbons produced in Western Europe and North America, CPs have recently come under increased regulatory scrutiny in Canada, the USA, and Europe, because of concerns about their environmental persistence, possible adverse effects on terrestrial and aquatic organisms, and potential carcinogenicity to humans. In both the monitoring of such contamination and the determination of the success of remediation methods, straightforward and inexpensive analytical methodology increases the ease of environmental assessment and facilitates regulatory enforcement. CPs have been considered to be incapable of being analyzed by GC. The authors report the solid phase microextraction (SPME) based analysis of CPs by GC using electron capture (EC) detection. Both synthetic C{sub 10} standards and fractionated commercially derived material have been analyzed by this method in water.

  17. Detection of chlorinated aromatic compounds

    DOEpatents

    Ekechukwu, A.A.

    1996-02-06

    A method for making a composition for measuring the concentration of chlorinated aromatic compounds in aqueous fluids, and an optical probe for use with the method are disclosed. The composition comprises a hydrophobic polymer matrix, preferably polyamide, with a fluorescent indicator uniformly dispersed therein. The indicator fluoresces in the presence of the chlorinated aromatic compounds with an intensity dependent on the concentration of these compounds in the fluid of interest, such as 8-amino-2-naphthalene sulfonate. The probe includes a hollow cylindrical housing that contains the composition in its distal end. The probe admits an aqueous fluid to the probe interior for exposure to the composition. An optical fiber transmits excitation light from a remote source to the composition while the indicator reacts with chlorinated aromatic compounds present in the fluid. The resulting fluorescence light signal is reflected to a second optical fiber that transmits the light to a spectrophotometer for analysis. 5 figs.

  18. Field-usable portable analyzer for chlorinated organic compounds

    SciTech Connect

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

    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.

  19. 40 CFR 704.43 - Chlorinated naphthalenes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... the chlorine atom(s) on the naphthalene. (4) Polychlorinated biphenyl means any chemical substance that is limited to the biphenyl molecule and that has been chlorinated to varying degrees. (5)...

  20. Inactivation of Helicobacter pylori by chlorination.

    PubMed Central

    Johnson, C H; Rice, E W; Reasoner, D J

    1997-01-01

    Three strains of Helicobacter pylori were studied to determine their resistance to chlorination. The organisms were readily inactivated by free chlorine and should therefore be controlled by disinfection practices normally employed in the treatment of drinking water. PMID:9406419

  1. 40 CFR 704.43 - Chlorinated naphthalenes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... the chlorine atom(s) on the naphthalene. (4) Polychlorinated biphenyl means any chemical substance that is limited to the biphenyl molecule and that has been chlorinated to varying degrees. (5)...

  2. 40 CFR 704.43 - Chlorinated naphthalenes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... the chlorine atom(s) on the naphthalene. (4) Polychlorinated biphenyl means any chemical substance that is limited to the biphenyl molecule and that has been chlorinated to varying degrees. (5)...

  3. 40 CFR 704.43 - Chlorinated naphthalenes.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... the chlorine atom(s) on the naphthalene. (4) Polychlorinated biphenyl means any chemical substance that is limited to the biphenyl molecule and that has been chlorinated to varying degrees. (5)...

  4. 40 CFR 704.43 - Chlorinated naphthalenes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... the chlorine atom(s) on the naphthalene. (4) Polychlorinated biphenyl means any chemical substance that is limited to the biphenyl molecule and that has been chlorinated to varying degrees. (5)...

  5. THE ROLE OF CHLORINE IN DIOXIN FORMATION

    EPA Science Inventory

    There is poor correlation between total chlorine in waste streams and formation of polychlorinated dibenzodioxin and polychlorinated dibenzofuran (PCDD/F) during waste combustion. This is because the active chlorine (Cl) species are strongly dependent upon combustion conditions. ...

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

    PubMed Central

    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 potential toxicity of the reaction products. Fatty acids and their methyl esters react with chlorine with the degree of incorporation corresponding to their degree of unsaturation. Aqueous chlorine oxidizes and chlorinates lipids and amino acids much more readily than ClO2. Several amino acids are highly susceptible to oxidation and chlorination by chlorine compounds. Reactions of chlorine and ClO2 with several food products, including flour and shrimp, have also been characterized. In one model system, 99% of Cl2(g) either reacted with components of flour or was consumed by oxidation/chlorination reactions. The lipids extracted from the chlorinated flour contained significant amounts of chlorine. Exposure of shrimp to hypochlorous acid (HOCl) solution resulted in significant incorporation of chlorine into the edible portion. Although significant quantities of chlorine can be incorporated into specific model compounds and food products, the health risks associated with exposure to chlorinated organic products are unknown. Preliminary studies using the Ames Salmonella/microsome mutagenicity assay indicate that the reaction products from mixtures of aqueous chlorine and various lipids or tryptophan are nonmutagenic. Nevertheless, additional studies are warranted, so that the toxicological significance of these reaction products can be understood more fully. PMID:3545804

  7. Reaction products from the chlorination of seawater. Final report 15 Jul 75-14 Jul 80

    SciTech Connect

    Carpenter, J.H.; Smith, C.A.; Zika, R.G.

    1981-03-01

    Chemical treatment of natural waters, in particular the use of chlorine as a biocide, modifies the chemistry of these waters in ways that are not fully understood. The research described in this report examined both inorganic and organic reaction products from the chlorination of seawater using a variety of analytical approaches. Some analytical methods in widespread current use underestimate the residual oxidants in chlorinated seawater by as much as 70% depending upon the detail of the procedures. The chlorination of seawater in the presence of light produces substantial quantities of bromate ions which can influence standard analytical procedures and represents an unknown factor in estuarine and coastal waters. The copper complexing capacity of Biscayne Bay, Florida water was found to be substantially reduced with the addition of chlorine. Analysis was made by anodic stripping voltammetry on water samples after successive additions of copper sulfate solution. Laboratory chlorination of water from the intake of the Port Everglades, Florida power plant produces bromoform levels comparable to that found in the plant discharge. These results are in contrast to results reported in the literature for a power plant on the Patuxent estuary in Maryland, so that bromoform production appears to be site-specific. Chloroform extracts of chlorinated Biscayne Bay water are found to contain halogenated compounds which are new and different, and which pose unusual analytical problems. Studies using GC/ECD, GC/MS, HPLC, H NMR, differential pulsed polarography and other techniques on natural extracts and synthesized compounds are reported.

  8. Radiolytic dechlorination of chlorinated organics

    NASA Astrophysics Data System (ADS)

    Taghipour, Fariborz; Evans, Greg J.

    1997-02-01

    The radiolytic dechlorination of 12 low molecular weight chlorinated organic compounds present in pulp mill effluent was investigated. For most of these chloro-organic compounds more than 90% dechlorination was obtained for gamma doses up to 20 kGy. Parameters such as the number of chlorine atoms and aqueous solution concentration were found to affect the dechlorination rate. A reaction set was also created to model the behavior of irradiated 0.49-49 mol m -3 chloroform solutions, giving good agreement with experimental results.

  9. Colorectal cancers and chlorinated water

    PubMed Central

    El-Tawil, Ahmed Mahmoud

    2016-01-01

    Published reports have revealed increased risk of colorectal cancers in people exposed to chlorinated drinking water or chemical derivatives of chlorination. Oestrogen plays a dual positive functions for diminishing the possibilities of such risk by reducing the entrance, and increasing the excretion, of these chemicals. In addition, there are supplementary measures that could be employed in order to reduce this risk further, such as boiling the drinking water, revising the standard concentrations of calcium, magnesium and iron in the public drinking water and prescribing oestrogen in susceptible individuals. Hypo-methylation of genomic DNA could be used as a biological marker for screening for the potential development of colorectal cancers. PMID:27096035

  10. Effect of moisture, charge size, and chlorine concentration on PCDD/F emissions from simulated open burning of forest biomass

    EPA Science Inventory

    Loblolly pine (Pinus taeda) was combusted at different charge sizes, fuel moisture, and chlorine content to determine the effect on emissions of polychlorinated dibenzo-p-dioxins and polychlorinated diberizofurans (PCDDslFs) as well as co-pollutants CO, PM, and total hydrocarbons...

  11. Environmental distribution of chlorinated organic pollutants

    SciTech Connect

    Emmi, F.

    1983-01-01

    A survey of the concentration of PCB's and chlorinated hydrocarbon pesticides in Susquehanna River Basin sediments was performed on samples collected from New York and Pennsylvania in 1976-1979. Highest concentrations were found for PCB's, with median and range of 38 and 13-524 ng/g, respectively. Pesticides had median concentrations ranging from approx.1 ng/g for DDT, DDD, and DDE, to less than 0.1 ng/g for aldrin and dieldrin. Highest concentrations generally were found downstream from industrial centers. Concentrations of PCB's and pesticides were also determined for soil composites collected from six areas of the basin. For several pollutants, the highest levels were found in the Pennsylvania areas, especially the Conestoga River Basin site. The PCB levels were the same (approx.35 ng/g) in all New York soil composites; this was consistent with concentrations predicted from known atmospheric deposition data. Adsorption of atrazine and simazine on model substrates was stuided to elucidate the partitioning of these herbicides on river sediments. Clean sea sand had little affinity for these compounds. Adsorption on illite clay and humic acid-coated sea sand gave relatively large K/sub p/ and K/sub oc/ values compared to the values for river sediments, suggesting that the nature of the sites available for absorbing organic molecules needs further study.

  12. STABLE CHLORINE ISOTOPE ANALYSIS OF CHLORINATED ORGANIC CONTAMINANTS

    EPA Science Inventory

    The biogeochemical cycling of chlorinated organic contaminants in the environment is often difficult to understand because of the complex distributions of these compounds and variability of sources. To address these issues from an isotopic perspective, we have measured the, 37Cl...

  13. 49 CFR 179.102-2 - Chlorine.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Chlorine. 179.102-2 Section 179.102-2... Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) § 179.102-2 Chlorine. (a) Each tank car used to transport chlorine must comply with all of the following: (1) Tanks must be fabricated from carbon...

  14. 49 CFR 179.102-2 - Chlorine.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Chlorine. 179.102-2 Section 179.102-2... Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) § 179.102-2 Chlorine. (a) Each tank car used to transport chlorine must comply with all of the following: (1) Tanks must...

  15. 49 CFR 179.102-2 - Chlorine.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Chlorine. 179.102-2 Section 179.102-2... Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) § 179.102-2 Chlorine. (a) Each tank car used to transport chlorine must comply with all of the following: (1) Tanks must be fabricated from carbon...

  16. 49 CFR 179.102-2 - Chlorine.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Chlorine. 179.102-2 Section 179.102-2... Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) § 179.102-2 Chlorine. (a) Each tank car used to transport chlorine must comply with all of the following: (1) Tanks must be fabricated from carbon...

  17. 49 CFR 179.102-2 - Chlorine.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Chlorine. 179.102-2 Section 179.102-2... Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) § 179.102-2 Chlorine. (a) Each tank car used to transport chlorine must comply with all of the following: (1) Tanks must be fabricated from carbon...

  18. An Easy Way To Make Chlorine Water

    NASA Astrophysics Data System (ADS)

    Holmes, L. H., Jr.

    1997-11-01

    Chlorine water can be made easily by mixing hypochlorite and hydrochloric acid. The equilibrium lies toward Cl2 in the reaction HOCl + HCl -> Cl2 + H2O and this can be used to make chlorine water from sodium hypochlorite and hydrochloric acid if the presence of NaCl in the chlorine water does not interfere with its use.

  19. CHLORINE DIOXIDE FOR DRINKING WATER RESEARCH DIVISION

    EPA Science Inventory

    In order to comply with the trihalomethane regulation, many drinking water utilities have had to alter their treatment methods. ne option available to these utilities is to use a disinfectant other than chlorine such as chlorine dioxide. ith chlorine dioxide disinfection, trihalo...

  20. BIODEGRADATION OF HYDROCARBON VAPORS IN THE UNSATURATED ZONE

    EPA Science Inventory

    The time-averaged concentration of hydrocarbon and oxygen vapors were measured in the unsaturated zone above the residually contaminated capillary fringe at the U.S. Coast Guard Air Station in Traverse City, Michigan. Total hydrocarbon and oxygen vapor concentrations were observe...

  1. Disinfectants: Chlorine and chlorine dioxide. (Latest citations from the Life Sciences Collection database). Published Search

    SciTech Connect

    Not Available

    1993-05-01

    The bibliography contains citations concerning the antimicrobial properties of chlorine and chlorine dioxide. The use of chlorine for the inactivation of viruses, bacteria, and fungi in wastewater treatment plants is discussed, including the mode of action and factors influencing inactivation. The use of chlorine dioxide as an alternative to chlorine disinfection in swimming pools and water supplies, and possible adverse effects are also discussed. (Contains a minimum of 157 citations and includes a subject term index and title list.)

  2. PREDICTING CHLORINE RESIDUAL LOSSES IN UNLINED METALIC PIPES

    EPA Science Inventory

    There is substantial evidence that as water moves through a water distribution system its quality can deteriorate through interactions between the bulk phase and the pipe wall. One of the most serious aspects of water quality deterioration, in a network, is the loss of disinfect...

  3. PREDICTING CHLORINE RESIDUAL LOSSES IN UNLINED METALLIC PIPES (POSTER)

    EPA Science Inventory

    There is substantial evidence that as water moves through a water distribution system its quality can deteriorate through interactions between the bulk phase and the pipe wall. One of the most serious aspects of water quality deterioration, in a network, is the loss of disinfect...

  4. PREDICTING CHLORINE RESIDUAL LOSSES IN UNLINED METALLIC PIPES (PRESENTATION)

    EPA Science Inventory

    There is substantial evidence that as water moves through a water distribution system its quality can deteriorate through interactions between the bulk phase and the pipe wall. One of the most serious aspects of water quality deterioration, in a network, is the loss of disinfecta...

  5. Factors promoting survival of bacteria in chlorinated water supplies.

    PubMed Central

    LeChevallier, M W; Cawthon, C D; Lee, R G

    1988-01-01

    Results of our experiments showed that the attachment of bacteria to surfaces provided the greatest increase in disinfection resistance. Attachment of unencapsulated Klebsiella pneumoniae grown in medium with high levels of nutrients to glass microscope slides afforded the microorganisms as much as a 150-fold increase in disinfection resistance. Other mechanisms which increased disinfection resistance included the age of the biofilm, bacterial encapsulation, and previous growth conditions (e.g., growth medium and growth temperature). These factors increased resistance to chlorine from 2- to 10-fold. The choice of disinfectant residual was shown to influence the type of resistance mechanism observed. Disinfection by free chlorine was affected by surfaces, age of the biofilm, encapsulation, and nutrient effects. Disinfection by monochloramine, however, was only affected by surfaces. Importantly, results showed that these resistance mechanisms were multiplicative (i.e., the resistance provided by one mechanism could be multiplied by the resistance provided by a second mechanism). PMID:3288119

  6. Second-generation photosensitizers based on natural chlorines and bacteriochlorines

    NASA Astrophysics Data System (ADS)

    Mironov, Andrei F.

    1996-01-01

    New sensitizers for photodynamic therapy were synthesized on the base of biologically generated chlorins and bacteriochlorins. Derivatives of chlorophyll a and bacteriochlorophyll were prepared from the biomass of blue-green algae Spirulina Platensis and purple bacteria Rhodobacter Capsulatus, generated using specially designed photobioreactor. The strategy for chemical transformation of natural chlorophylls and bacteriochlorophyll has been discussed. Purpurin 18 and its dihydroanalogue bacteriopurpurin were chosen as the key intermediates. Modifications of peripheral substituents, such as introducing the new functional groups, hydrogenation of the B-pyrrolic ring, and insertion of amino acid residues gave the series of novel sensitizers, including water soluble chlorin p6 analogues, and derivatives with graded amphiphility for the studies of tumor accumulation in the malignant tissues.

  7. The Chlorine Isotopic Composition Of Lunar UrKREEP

    NASA Technical Reports Server (NTRS)

    Barnes, J. J.; Tartese, R.; Anand, M.; McCubbin, F. M.; Neal, C. R.; Franchi, I. A.

    2016-01-01

    Since the long standing paradigm of an anhydrous Moon was challenged there has been a renewed focus on investigating volatiles in a variety of lunar samples. Numerous studies have examined the abundances and isotopic compositions of volatiles in lunar apatite, Ca5(PO4)3(F,Cl,OH). In particular, apatite has been used as a tool for assessing the sources of H2O in the lunar interior. However, current models for the Moon's formation have yet to fully account for its thermal evolution in the presence of H2O and other volatiles. For ex-ample, in the context of the lunar magma ocean (LMO) model, it is anticipated that chlorine (and other volatiles) should have been concentrated in the late-stage LMO residual melts (i.e., the dregs enriched in incompatible elements such as K, REEs (Rare Earth Elements), and P, collectively called KREEP, and in its primitive form - urKREEP, given its incompatibility in mafic minerals like olivine and pyroxene, which were the dominant phases that crystallized early in the cumulate pile of the LMO. When compared to chondritic meteorites and terrestrial rocks, lunar samples have exotic chlorine isotope compositions, which are difficult to explain in light of the abundance and isotopic composition of other volatile species, especially H, and the current estimates for chlorine and H2O in the bulk silicate Moon (BSM). In order to better understand the processes involved in giving rise to the heavy chlorine isotope compositions of lunar samples, we have performed a comprehensive in situ high precision study of chlorine isotopes in lunar apatite from a suite of Apollo samples covering a range of geochemical characteristics and petrologic types.

  8. NATURAL ATTENUATION OF CHLORINATED SOLVENTS

    EPA Science Inventory

    The protocol will simply describe in detail, with references and illustrations, the approach currently used by staff of the SPRD to evaluate natural attenuation of chlorinated solvents in ground water. Staff of SPRD, and staff of the Air Force Center for environmental excellence...

  9. VOLTAMMETRIC MEMBRANE CHLORINE DIOXIDE ELECTRODE

    EPA Science Inventory

    A voltammetric membrane electrode system has been modified and applied to the in situ measurement of chlorine dioxide. The electrode system consisted of a gold cathode, a silver/silver chloride reference electrode, and a gold counter electrode. Different membrane materials were t...

  10. Chlorine Abundances in Martian Meteorites

    NASA Technical Reports Server (NTRS)

    Bogard, D.D.; Garrison, D.H.; Park, J.

    2009-01-01

    Chlorine measurements made in martian surface rocks by robotic spacecraft typically give Chlorine (Cl) abundances of approximately 0.1-0.8%. In contrast, Cl abundances in martian meteorites appear lower, although data is limited, and martian nakhlites were also subjected to Cl contamination by Mars surface brines. Chlorine abundances reported by one lab for whole rock (WR) samples of Shergotty, ALH77005, and EET79001 range 108-14 ppm, whereas Cl in nakhlites range 73-1900 ppm. Measurements of Cl in various martian weathering phases of nakhlites varied 0.04-4.7% and reveal significant concentration of Cl by martian brines Martian meteorites contain much lower Chlorine than those measured in martian surface rocks and give further confirmation that Cl in these surface rocks was introduced by brines and weathering. It has been argued that Cl is twice as effective as water in lowering the melting point and promoting melting at shallower martian depths, and that significant Cl in the shergottite source region would negate any need for significant water. However, this conclusion was based on experiments that utilized Cl concentrations more analogous to martian surface rocks than to shergottite meteorites, and may not be applicable to shergottites.

  11. Characterization and identification of a chlorine-resistant bacterium, Sphingomonas TS001, from a model drinking water distribution system.

    PubMed

    Sun, Wenjun; Liu, Wenjun; Cui, Lifeng; Zhang, Minglu; Wang, Bei

    2013-08-01

    This study describes the identification and characterization of a new chlorine resistant bacterium, Sphingomonas TS001, isolated from a model drinking water distribution system. The isolate was identified by 16s rRNA gene analysis and morphological and physiological characteristics. Phylogenetic analysis indicates that TS001 belongs to the genus Sphingomonas. The model distribution system HPC results showed that, when the chlorine residual was greater than 0.7 mg L(-1), 100% of detected heterotrophic bacteria (HPC) was TS001. The bench-scale inactivation efficiency testing showed that this strain was very resistant to chlorine, and 4 mg L(-1) of chlorine with 240 min retention time provided only approximately 5% viability reduction of TS001. In contrast, a 3-log inactivation (99.9%) was obtained for UV fluencies of 40 mJ cm(-2). A high chlorine-resistant and UV sensitive bacterium, Sphingomonas TS001, was documented for the first time. PMID:23648446

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

    PubMed

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

    2011-01-01

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

  13. Environmental factors regulating soil organic matter chlorination

    NASA Astrophysics Data System (ADS)

    Svensson, Teresia; Montelius, Malin; Reyier, Henrik; Rietz, Karolina; Karlsson, Susanne; Lindberg, Cecilia; Andersson, Malin; Danielsson, Åsa; Bastviken, David

    2016-04-01

    Natural chlorination of organic matter is common in soils. Despite the widespread abundance of soil chlorinated soil organic matter (SOM), frequently exceeding soil chloride abundance in surface soils, and a common ability of microorganisms to produce chlorinated SOM, we lack fundamental knowledge about dominating processes and organisms responsible for the chlorination. To take one step towards resolving the terrestrial chlorine (Cl) puzzle, this study aims to analyse how environmental factors influence chlorination of SOM. Four factors were chosen for this study: soil moisture (W), nitrogen (N), chloride (Cl) and organic matter quality (C). These factors are all known to be important for soil processes. Laboratory incubations with 36Cl as a Cl tracer were performed in a two soil incubation experiments. It was found that addition of chloride and nitrogen seem to hamper the chlorination. For the C treatment, on the other hand, the results show that chlorination is enhanced by increased availability of labile organic matter (glucose and maltose). Even higher chlorination was observed when nitrogen and water were added in combination with labile organic matter. The effect that more labile organic matter strongly stimulated the chlorination rates was confirmed by the second separate experiment. These results indicate that chlorination was not primarily a way to cut refractory organic matter into digestible molecules, representing one previous hypothesis, but is related with microbial metabolism in other ways that will be further discussed in our presentation.

  14. Geochemical methods of prospecting for hydrocarbons

    SciTech Connect

    Duchscherer, W. Jr.

    1980-12-01

    Because the commonly used reflection-seismograph exploration technique misses many marginal low-relief structural prospects and regardless of its electronic computer sophistication, overlooks almost all stratigraphic traps, the hydrocarbon exploration industry should take a look at geochemical prospecting methods, which detect geochemical anomalies in the near-surface soils by measuring the thermal dissociation of the soil carbonates that are found overlying hydrocarbon accumulations. To promote understanding of such prospecting techniques, Geochemical Surveys reviews the methods used, the soil-alteration patterns, the lateral and vertical migration of hydrocarbon gases, the halo phenomenon (a ring or annual anomaly), the geochemical modification of sediments, and the data-interpretation and exploration procedures involved in a carbonate ..delta.. C analysis, which measures the residual, stable, cumulative effect of hydrocarbon migration.

  15. Distribution and chemical fate of chlorine dioxide gas during sanitation of tomatoes and cantaloupe

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A series of studies was conducted to establish the 1) distribution and chemical fate of 36-ClO2 on tomatoes and cantaloupe; and 2) the magnitude of residues in kilogram quantities of tomatoes and cantaloupe sanitized with a slow-release chlorine dioxide formulation. Tomatoes and cantaloupe were resp...

  16. Evidence for a pore-filling mechanism in the adsorption of aromatic hydrocarbons to a natural wood char.

    PubMed

    Nguyen, Thanh H; Cho, Hyun-Hee; Poster, Dianne L; Ball, William P

    2007-02-15

    Sorption isotherms for five aromatic hydrocarbons were obtained with a natural wood char (NC1) and its residue after solvent extraction (ENC1). Substantial isotherm nonlinearity was observed in all cases. ENC1 showed higher BET surface area, higher nitrogen-accessible micropore volume, and lower mass of extractable organic chemicals, including quantifiable polycyclic aromatic hydrocarbons (PAHs),while the two chars showed identical surface oxygen/ carbon (O/C) ratio. For two chlorinated benzenes that normally condense as liquids at the temperatures used, sorption isotherms with NC1 and ENC1 were found to be statistically identical. For the solid-phase compounds (1,4-dichlorobenzene (1,4-DCB) and two PAHs), sorption was statistically higher with ENC1, thus demonstrating sorption effects due to both (1) authigenic organic content in the sorbentand (2)the sorbate's condensed state. Polanyi-based isotherm modeling, pore size measurements, and comparisons with activated carbon showthe relative importance of adsorptive pore filling and help explain results. With both chars, maximum sorption increased in the order of decreasing molecular diameter: phenanthrene < naphthalene < 1,2-dichlorobenzene/1,2,4-trichlorobenzene < 1,4-DCB. Comparison of 1,4- and 1,2-DCB shows that the critical molecular diameter was apparently more important than the condensed state, suggesting that 1,4-DCB sorbed in the liquid state for ENC1. PMID:17593721

  17. Formation and destruction of the aromatic products of incomplete combustion (PICs) during the chlorinated organic compounds incineration in a lab-scale combustor

    SciTech Connect

    Lin, C.; Li, W.S.; Chen, S.J.; Jeng, R.S.; Chan, C.P.

    1999-07-01

    Thermal destruction is one of the most effective processes to treat organic waste in view of the volume reduction. However, some pollutant emissions associated with waste incineration have led to reluctance to apply this state-of art technology. Proper control of the incineration process with respect to operating parameters to produce flue gases acceptable to the environment is essential for the success of this approach. Better understanding the mechanism of combustion in an incinerator will help the design of more efficient combustion devices. The objective of this research is to investigate the key operating parameters related to the performance of an incinerator using a heterogeneous laboratory scale spouted bed combustor. The spouted bed is considered as an innovative type of fluidized bed and provided with a small centrally located inlet aperture in its conical base which allows a jet of fluid to enter. The ability to use low heat value fuels due to heat recirculation inside the bed and low pollutants emission levels brought down by the long residence time stimulate the application of this combustor in laboratory research. Formation and destruction of the aromatic products of incomplete combustion (PICs) in the post-combustion region for burning toluene and PVC (polyvinyl chloride) is under investigation in this study. The residual hydrocarbons and chlorinated hydrocarbons species are measured. The primary compounds including aromatics, substituted aromatics, and polycyclic aromatics hydrocarbons (PAHs) are formed and destroyed during flue gas passing through the low temperature region. The flue gas samples are induced from the side probes along the reactor with constant flow rate and simultaneously to monitor the temperature by using thermocouples. The sampling train consists of a fiber glass filter and an impinger.

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

    SciTech Connect

    Sturchio, N.C.; Heraty, L.J.; Huang, L.; Holt, B.D.; Abrajano, T.A. Jr.; Clausen, J.L.

    1998-10-15

    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.

  19. Ordered chlorinated monolayer silicene structures

    NASA Astrophysics Data System (ADS)

    Li, Wenbin; Sheng, Shaoxiang; Chen, Jian; Cheng, Peng; Chen, Lan; Wu, Kehui

    2016-04-01

    We report on a systematic experimental study on the chlorination of monatomic silicene layer on Ag(111) by scanning tunneling microscopy. Monolayer silicene on Ag(111) can form 4×4, (√13×√13)R ± 13.9°, and (2√3×2√3)R30° reconstructions due to their different buckling configurations. We found that at low dosage, Cl atoms attach to the upper buckled Si atoms without changing the buckling configuration of the silicene monolayer. However, at high coverage, the global buckling configuration will be significantly changed, resulting in new ordered structures. Interestingly, all monolayer silicene structures, regardless of their initial reconstructions, tend to form a local silicene 1×1 structure at the saturation coverage. The mechanism for chlorination of monolayer silicene is explained.

  20. Chlorine signal attenuation in concrete.

    PubMed

    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. PMID:26218450

  1. Detection of chlorinated aromatic compounds

    DOEpatents

    Ekechukwu, Amy A.

    1996-01-01

    A method for making a composition for measuring the concentration of chloated aromatic compounds in aqueous fluids, and an optical probe for use with the method. The composition comprises a hydrophobic polymer matrix, preferably polyamide, with a fluorescent indicator uniformly dispersed therein. The indicator fluoresces in the presence of the chlorinated aromatic compounds with an intensity dependent on the concentration of these compounds in the fluid of interest, such as 8-amino-2-naphthalene sulfonate. The probe includes a hollow cylindrical housing that contains the composition in its distal end. The probe admits an aqueous fluid to the probe interior for exposure to the composition. An optical fiber transmits excitation light from a remote source to the composition while the indicator reacts with chlorinated aromatic compounds present in the fluid. The resulting fluorescence light signal is reflected to a second optical fiber that transmits the light to a spectrophotometer for analysis.

  2. Coal desulfurization by aqueous chlorination

    NASA Technical Reports Server (NTRS)

    Kalvinskas, J. J.; Vasilakos, N.; Corcoran, W. H.; Grohmann, K.; Rohatgi, N. K. (Inventor)

    1982-01-01

    A method of desulfurizing coal is described in which chlorine gas is bubbled through an aqueous slurry of coal at low temperature below 130 degrees C., and at ambient pressure. Chlorinolysis converts both inorganic and organic sulfur components of coal into water soluble compounds which enter the aqueous suspending media. The media is separated after chlorinolysis and the coal dechlorinated at a temperature of from 300 C to 500 C to form a non-caking, low-sulfur coal product.

  3. Microbial based chlorinated ethene destruction

    DOEpatents

    Bagwell, Christopher E.; Freedman, David L.; Brigmon, Robin L.; Bratt, William B.; Wood, Elizabeth A.

    2009-11-10

    A mixed culture of Dehalococcoides species is provided that has an ability to catalyze the complete dechlorination of polychlorinated ethenes such as PCE, TCE, cDCE, 1,1-DCE and vinyl chloride as well as halogenated ethanes such as 1,2-DCA and EDB. The mixed culture demonstrates the ability to achieve dechlorination even in the presence of high source concentrations of chlorinated ethenes.

  4. Hydrocarbon release investigations in Missouri

    SciTech Connect

    Fels, J.B.

    1996-09-01

    Hydrocarbon releases are among the most common environmental problems in Missouri, as well as across the country. Old, unprotected underground storage tanks and buried piping from the tanks to pumps are notorious sources of petroleum contamination at LUST (leaking underground storage tank) sites. Missouri has an estimated 5000 LUST sites across the state with the majority being simple spills into clay-rich soils or into a shallow perched water system. However, in the southern half of the state, where residual soils and karst bedrock are not conducive to trapping such releases, significant groundwater supplies are at risk. This article discusses the process used to identify the source of contamination.

  5. Detection of sewage organic chlorination products that are resistant to dechlorination with sulfite

    SciTech Connect

    MacCrehan, W.A.; Jensen, J.S.; Helz, G.R.

    1998-11-15

    Most of the 36 billion gal of treated sewage wastewater discharged daily into the environment in the United States is disinfected via chlorination. To minimize toxicity. dechlorination with sulfite or sulfur dioxide is often performed. Although dechlorination is considered instantaneous and complete, several studies have found residual toxicity of chlorinated/dechlorinated effluent to aquatic life. The authors investigated chlorination/dechlorination of the organic nitrogen components of sewage wastewater using both iodometric titration and a novel LC method. For LC, a postcolumn reaction with iodide rendered submicromolar chloramine concentrations detectable with amperometry. Using a gradient-elution LC separation, the retention and dechlorination behavior of a suite of model amines was determined, representing primary and secondary aliphatic, peptide, and protein-N. Chlorination/dechlorination experiments on freshly collected, tertiary-treated wastewater showed a fraction of the organic N-chloramines are dechlorinated slowly by sulfite with half-lives of >20 min. Chromatographic retention and kinetic behavior of the sewage N-chloramines was consistent with the behavior of the model peptides and proteins. Proteolytic hydrolysis markedly increased the peptide fraction observed upon chlorination of the wastewater. These results suggest that peptides and proteins contribute to slow dechlorination of sewage and may be a factor in the toxicity noted for chlorine-disinfected wastewater.

  6. Bacterial Community Shift Drives Antibiotic Resistance Promotion during Drinking Water Chlorination.

    PubMed

    Jia, Shuyu; Shi, Peng; Hu, Qing; Li, Bing; Zhang, Tong; Zhang, Xu-Xiang

    2015-10-20

    For comprehensive insights into the effects of chlorination, a widely used disinfection technology, on bacterial community and antibiotic resistome in drinking water, this study applied high-throughput sequencing and metagenomic approaches to investigate the changing patterns of antibiotic resistance genes (ARGs) and bacterial community in a drinking water treatment and distribution system. At genus level, chlorination could effectively remove Methylophilus, Methylotenera, Limnobacter, and Polynucleobacter, while increase the relative abundance of Pseudomonas, Acidovorax, Sphingomonas, Pleomonas, and Undibacterium in the drinking water. A total of 151 ARGs within 15 types were detectable in the drinking water, and chlorination evidently increased their total relative abundance while reduced their diversity in the opportunistic bacteria (p < 0.05). Residual chlorine was identified as the key contributing factor driving the bacterial community shift and resistome alteration. As the dominant persistent ARGs in the treatment and distribution system, multidrug resistance genes (mainly encoding resistance-nodulation-cell division transportation system) and bacitracin resistance gene bacA were mainly carried by chlorine-resistant bacteria Pseudomonas and Acidovorax, which mainly contributed to the ARGs abundance increase. The strong correlation between bacterial community shift and antibiotic resistome alteration observed in this study may shed new light on the mechanism behind the chlorination effects on antibiotic resistance. PMID:26397118

  7. Comparison of laboratory and field avoidance behavior of fish in heated chlorinated water

    SciTech Connect

    Giattina, J.D.; Cherry, D.S.; Cairns, J. Jr.; Larrick, S.R.

    1981-07-01

    The effects of intermittent chlorination and temperature selection on the movement of fish were studied in an integrated field and laboratory project on the New River at the Glen Lyn Power Plant in southwestern Virginia. Over a temperature range of 7 to 36 C, the total number of fish sampled from the intermittently chlorinated thermal effluent was lower than control values (P less than or equal to 0.09) when total residual chlorine (TRC) concentration were greater than or equal to 0.15 mg/liter. After seasonal variations were segregated into discrete intervals of field temperature and fish avoidance of TRC, a decline in fish abundance in the chlorinated, heated discharge was observed within 95% confidence limits. In summer field temperatures of 27 to 30 C, fish avoided a TRC concentration that ranged from 0.19 to 0.28 mg/liter TRC; when temperatures were falling from 26 to 7 C, they avoided 0.23 to 0.24 mg/liter TRC. In most cases, laboratory-determined avoidance concentrations predicted accurately the TRC concentrations that would elicit the avoidance behavior of fish under natural field conditions. Based on published acute toxicity tests with intermittent chlorination, spotfin shiners and most other fish species generally avoided chlorien residuals 50% or less of the median lethal concentrations.

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

    PubMed

    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. PMID:27441859

  9. UV/chlorine process for ammonia removal and disinfection by-product reduction: comparison with chlorination.

    PubMed

    Zhang, Xinran; Li, Weiguang; Blatchley, Ernest R; Wang, Xiaoju; Ren, Pengfei

    2015-01-01

    The combined application of UV irradiation at 254 nm and chlorination (UV/chlorine process) was investigated for ammonia removal in water treatment. The UV/chlorine process led to higher ammonia removal with less chlorine demand, as compared to breakpoint chlorination. Chlorination of NH₃ led to NH₂Cl formation in the first step. The photolysis of NH₂Cl and radical- mediated oxidation of ammonia appeared to represent the main pathways for ammonia removal. The trivalent nitrogen of ammonia was oxidized, presumably by reactions with aminyl radicals and chlorine radicals. Measured products included NO₃⁻and NO₂⁻; it is likely that N₂ and N₂O were also generated. In addition, UV irradiation appeared to have altered the reactivity of NOM toward free chlorine. The UV/chlorine process had lower chlorine demand, less C-DBPs (THMs and HAAs), but more HANs than chlorination. These results indicate that the UV/chlorine process could represent an alternative to conventional breakpoint chlorination for ammonia-containing water, with several advantages in terms of simplicity, short reaction time, and reduced chemical dosage. PMID:25466638

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

    SciTech Connect

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

    1986-11-01

    This presentation reviews published information concerning the reactions of chlorine gas (CL/sub 2/(g)), aqueous chlorine, and ClO/sub 2/ with model food compounds, the fate of chlorine during the chlorination of specific food products, and the potential toxicity of the reaction products. Fatty acids and their methyl esters react with chlorine with the degree of incorporation corresponding to their degree of unsaturation. Aqueous chlorine oxidizes and chlorinates lipids and amino acids much more readily than ClO/sub 2/. Several amino acids are highly susceptible to oxidation and chlorination by chlorine compounds. Reactions of chlorine and ClO/sub 2/ with several food products, including flour and shrimp, have also been characterized. Although significant quantities of chlorine can be incorporated into specific model compounds and food products, the health risks associated with exposure to chlorinated organic products are unknown. Preliminary studies using the Ames Salmonella/microsome mutagenicity assay indicate that the reaction products from mixtures of aqueous chlorine and various lipids or tryptophan are nonmutagenic. Nevertheless, additional studies are warranted, so that the toxicological significance of these reaction products can be understood more fully.

  11. Observations of interstellar chlorine and phosphorus

    NASA Technical Reports Server (NTRS)

    Jura, M.; York, D. G.

    1978-01-01

    Copernicus observations of interstellar Cl I, Cl II, and P II UV lines toward 10 stars are reported. Column densities are estimated for each species, and upper limits are computed for HCl column densities. Derivation of the gas-phase abundances of chlorine and phosphorus indicates that the averages of both the chlorine and the phosphorus logarithmic abundances relative to hydrogen are between 5.0 and 5.1. It is suggested that interstellar chlorine may be depleted by about a factor of 3 relative to the solar abundance and that interstellar phosphorus is depleted by a factor of 2 to 3. The results are shown to support the prediction that chlorine is ionized in regions containing primarily atomic oxygen and is neutral in regions where there is a significant amount of molecular hydrogen. The photoionization rate of neutral chlorine toward 15 Mon is estimated, and it is concluded that most chlorine is contained within the gas phase.

  12. IDENTIFICATION OF DRINKING WATER DISINFECTION BY-PRODUCTS FROM OZONE, CHLORINE DIOXIDE, CHLORAMINE, AND CHLORINE

    EPA Science Inventory

    Many drinking water treatment plants are currently using alternative disinfectants to treat drinking water, with ozone, chlorine dioxide, and chloramine being the most popular. However, compared to chlorine, which has been much more widely studied, there is little information abo...

  13. EVALUATION OF MUTAGENIC AND CARCINOGENIC PROPERTIES OF BROMINATED AND CHLORINATED ACETONITRILES: BY-PRODUCTS OF CHLORINATION

    EPA Science Inventory

    The present study was undertaken to determine if chlorinated and brominated acetonitriles formed during the chlorination of drinking water possess mutagenic and/or carcinogenic properties. Chloroacetonitrile (CAN), dichloroacetonitrile (DCAN), trichloroacetonitrile (TCAN), bromoc...

  14. Foaming of mixtures of pure hydrocarbons

    NASA Technical Reports Server (NTRS)

    Robinson, J. V.; Woods, W. W.

    1950-01-01

    Mixtures of pure liquid hydrocarbons are capable of foaming. Nine hydrocarbons were mixed in pairs, in all possible combinations, and four proportions of each combination. These mixtures were sealed in glass tubes, and the foaming was tested by shaking. Mixtures of aliphatic with other aliphatic hydrocarbons, or of alkyl benzenes with other alkyl benzenes, did not foam. Mixtures of aliphatic hydrocarbons with alkyl benzenes did foam. The proportions of the mixtures greatly affected the foaming, the maximum foaming of 12 of 20 pairs being at the composition 20 percent aliphatic hydrocarbon, 80 percent alkyl benzene. Six seconds was the maximum foam lifetime of any of these mixtures. Aeroshell 120 lubricating oil was fractionated into 52 fractions and a residue by extraction with acetone in a fractionating extractor. The index of refraction, foam lifetime, color, and viscosity of these fractions were measured. Low viscosity and high index fractions were extracted first. The viscosity of the fractions extracted rose and the index decreased as fractionation proceeded. Foam lifetimes and color were lowest in the middle fractions. Significance is attached to the observation that none of the foam lifetimes of the fractions or residue is as high as the foam lifetime of the original Aeroshell, indicating that the foaming is not due to a particular foaming constituent, but rather to the entire mixture.

  15. Enhancing the efficacy of electrolytic chlorination for ballast water treatment by adding carbon dioxide.

    PubMed

    Cha, Hyung-Gon; Seo, Min-Ho; Lee, Heon-Young; Lee, Ji-Hyun; Lee, Dong-Sup; Shin, Kyoungsoon; Choi, Keun-Hyung

    2015-06-15

    We examined the synergistic effects of CO2 injection on electro-chlorination in disinfection of plankton and bacteria in simulated ballast water. Chlorination was performed at dosages of 4 and 6ppm with and without CO2 injection on electro-chlorination. Testing was performed in both seawater and brackish water quality as defined by IMO G8 guidelines. CO2 injection notably decreased from the control the number of Artemia franciscana, a brine shrimp, surviving during a 5-day post-treatment incubation (1.8 and 2.3 log10 reduction in seawater and brackish water, respectively at 6ppm TRO+CO2) compared with water electro-chlorinated only (1.2 and 1.3 log10 reduction in seawater and brackish water, respectively at 6ppm TRO). The phytoplankton Tetraselmis suecica, was completely disinfected with no live cell found at >4ppm TRO with and without CO2 addition. The effects of CO2 addition on heterotrophic bacterial growth was not different from electro-chlorination only. Total residual oxidant concentration (TRO) more rapidly declined in electro-chlorination of both marine and brackish waters compared to chlorine+CO2 treated waters, with significantly higher amount of TRO being left in waters treated with the CO2 addition. Total concentration of trihalomethanes (THMs) and haloacetic acids (HAAs) measured at day 0 in brackish water test were found to be 2- to 3-fold higher in 6ppm TRO+CO2-treated water than in 6ppm TRO treated water. The addition of CO2 to electro-chlorination may improve the efficiency of this sterilizing treatment of ballast water, yet the increased production of some disinfection byproducts needs further study. PMID:25841887

  16. COMBINING METHODS FOR THE REDUCTION OF OXYCHLORINE RESIDUALS IN DRINKING WATER

    EPA Science Inventory

    Previous investigations have shown ferrous iron application to be an effective and economically feasible method of removing residual chlorine dioxide and chlorite iron from drinking water. This treatment, however, was not effective in reducing concentrqations of chlorate iron. ...

  17. Factors influencing the formation of haloforms in the chlorination of humic materials

    SciTech Connect

    Peters, C.J.; Young, R.J.; Perry, R.

    1980-11-01

    Examined are the reactions of chlorine with humic and fulvic fractions extracted from the River Thames and tested under controlled conditions of pH and temperature. Also studied is the relationship between residual haloforms and total haloform formation from these acid fractions under conditions generally encountered in water treatment. Monitoring of chloroform production indicates that total chloroform is composed of two components: one produced by thermal decomposition of unidentified chlorinated intermediates and the other dissolved chloroform. The dominant factor influencing both the production of total chloroform and the relative proportions of these two components is pH. (2 drawings, 5 graphs, 15 references, 2 tables)

  18. A kinetics investigation of several reactions involving chlorine containing compounds

    NASA Technical Reports Server (NTRS)

    Davis, D. D.

    1978-01-01

    The technique of flash photolysis-resonance fluorescence was utilized to study nine reactions of stratospheric importance. The tropospheric degradation reactions of seven halogenated hydrocarbons were studied to assess their possible influx into the stratosphere. There are reactions of either Cl, OH, or O(3P) species with hydrogenated species, O3 or chlorinated compounds. Apart from the kinetic measurements, the quantum yield for the production of O(1D) from O3 in the crucial wavelength region of 293 to 316.5 nm was studied by utilizing a narrow wavelength laser as the photolysis source. The product formation was monitored by measuring the fluorescence of NO2 formed through O(1D) reaction with N2O followed by NO reaction with O3 to give NO2.

  19. Dechlorination of chlorine compounds in poly(vinyl chloride) mixed plastics derived oil by solid sorbents

    SciTech Connect

    Uddin, M.A.; Sakata, Yusaku; Shiraga, Yoshitaka; Muto, Akinori; Murata, Katsuhide

    1999-04-01

    The degradation of poly(ethylene) (PE) (i g)/poly(vinyl chloride) (2 g) at 430 C, poly(propylene) (PP) (8 g)/PVC (2 /g) at 380 C, and poly(styrene) (PS) (8 g) at 360 C into fuel oil was carried out in a glass reactor under atmospheric pressure by batch operation. The purpose of this study is to determine the composition of the products of the degradation of PVC mixed plastics and to remove chlorine compounds from products with suitable sorbents. The organic chlorine compounds were distributed in the boiling point (bp) range of 36--174 C (equivalent to the bps of n-C{sub 6} to n-C{sub 10}) for PE/PVC and PP/PVC and 36--195 C for PS/PVC. These compounds are thought to be produced by the reaction between the hydrogen chloride originating from PVC and the hydrocarbons obtained from the degradation of PE, PP, and PS. The degradation of the PP/PVC mixture was also carried out in the presence of a silica-alumina (SA1) catalyst, which is known as an effective catalyst for the degradation of hydrocarbons, and iron oxides (FeOOH, Fe{sub 2}O{sub 3}, and Fe{sub 3}O{sub 4}), as chlorine sorbents. Compared to thermal degradation, the SA1 catalyst accelerated the rate of degradation and lowered the bp of products, and the iron oxides FeOOH and Fe{sub 3}O{sub 4} decreased the chlorine content in the oil to a very low level. The authors suggest that the chlorine removed from the products of degradation of PVC mixed plastics are fixed in the form of iron compounds such as ferrous chloride.

  20. Chlorine fate and transport in drinking water distribution systems: Results from experimental and modeling studies

    NASA Astrophysics Data System (ADS)

    Clark, Robert M.

    2011-12-01

    It has become generally accepted that water quality can deteriorate in a distribution system through microbiological and chemical reactions in the bulk phase and/or at the pipe wall. The most serious aspect of water quality deterioration in a network is the loss of the disinfectant residual that can weaken the barrier against microbial contamination. Studies have suggested that one factor contributing to the loss of disinfectant residuals is the reaction between bulk phase disinfectants and pipe wall material. Free chlorine loss in corroded metal and PVC pipes, subject to changes in velocity, was assessed during an experiment conducted under controlled conditions in a specially constructed pipe loop located at the US Environmental Protection Agency's (EPA's) Test and Evaluation (T&E) Facility in Cincinnati, Ohio (USA). These studies demonstrated that in older unlined metal pipes, the loss of chlorine residual increases with velocity but that wall demand in PVC was negligible.

  1. Decontamination of Pangasius fish (Pangasius hypophthalmus) with chlorine or peracetic acid in the laboratory and in a Vietnamese processing company.

    PubMed

    Tong Thi, Anh Ngoc; Sampers, Imca; Van Haute, Sam; Samapundo, Simbarashe; Ly Nguyen, Binh; Heyndrickx, Marc; Devlieghere, Frank

    2015-09-01

    This study evaluated the decontamination of Pangasius fillets in chlorine or peracetic acid treated wash water. First, the decontamination efficacy of the washing step with chlorinated water applied by a Vietnamese processing company during trimming of Pangasius fillets was evaluated and used as the basis for the experiments performed on a laboratory scale. As chlorine was only added at the beginning of the batch and used continuously without renewal for 239min; a rapid increase of the bacterial counts and a fast decrease of chlorine in the wash water were found. This could be explained by the rapid accumulation of organic matter (ca. 400mg O2/L of COD after only 24min). Secondly, for the experiments performed on a laboratory scale, a single batch approach (one batch of wash water for treating a fillet) was used. Chlorine and PAA were evaluated at 10, 20, 50 and 150ppm at contact times of 10, 20 and 240s. Washing with chlorine and PAA wash water resulted in a reduction of Escherichia coli on Pangasius fish which ranged from 0-1.0 and 0.4-1.4logCFU/g, respectively while less to no reduction of total psychrotrophic counts, lactic acid bacteria and coliforms on Pangasius fish was observed. However, in comparison to PAA, chlorine was lost rapidly. As an example, 53-83% of chlorine and 15-17% of PAA were lost after washing for 40s (COD=238.2±66.3mg O2/L). Peracetic acid can therefore be an alternative sanitizer. However, its higher cost will have to be taken into consideration. Where (cheaper) chlorine is used, the processors have to pay close attention to the residual chlorine level, pH and COD level during treatment for optimal efficacy. PMID:26058007

  2. Optimal design and operation of booster chlorination stations layout in water distribution systems.

    PubMed

    Ohar, Ziv; Ostfeld, Avi

    2014-07-01

    This study describes a new methodology for the disinfection booster design, placement, and operation problem in water distribution systems. Disinfectant residuals, which are in most cases chlorine residuals, are assumed to be sufficient to prevent growth of pathogenic bacteria, yet low enough to avoid taste and odor problems. Commonly, large quantities of disinfectants are released at the sources outlets for preserving minimum residual disinfectant concentrations throughout the network. Such an approach can cause taste and odor problems near the disinfectant injection locations, but more important hazardous excessive disinfectant by-product formations (DBPs) at the far network ends, of which some may be carcinogenic. To cope with these deficiencies booster chlorination stations were suggested to be placed at the distribution system itself and not just at the sources, motivating considerable research in recent years on placement, design, and operation of booster chlorination stations in water distribution systems. The model formulated and solved herein is aimed at setting the required chlorination dose of the boosters for delivering water at acceptable residual chlorine and TTHM concentrations for minimizing the overall cost of booster placement, construction, and operation under extended period hydraulic simulation conditions through utilizing a multi-species approach. The developed methodology links a genetic algorithm with EPANET-MSX, and is demonstrated through base runs and sensitivity analyses on a network example application. Two approaches are suggested for dealing with water quality initial conditions and species periodicity: (1) repetitive cyclical simulation (RCS), and (2) cyclical constrained species (CCS). RCS was found to be more robust but with longer computational time. PMID:24762553

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

    PubMed

    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

  4. Chlorine isotope analysis of organic contaminants using GC-qMS: method optimization and comparison of different evaluation schemes.

    PubMed

    Jin, Biao; Laskov, Christine; Rolle, Massimo; Haderlein, Stefan B

    2011-06-15

    Compound-specific online chlorine isotope analysis of chlorinated hydrocarbons was evaluated and validated using gas chromatography coupled to a regular quadrupole mass spectrometer (GC-qMS). This technique avoids tedious off-line sample pretreatments, but requires mathematical data analysis to derive chlorine isotope ratios from mass spectra. We compared existing evaluation schemes to calculate chlorine isotope ratios with those that we modified or newly proposed. We also tested systematically important experimental procedures such as external vs. internal referencing schemes, and instrumental settings including split ratio, ionization energy, and dwell times. To this end, headspace samples of tetrachloroethene (PCE), trichloroethene (TCE), and cis-dichloroethene (cDCE) at aqueous concentrations in the range of 20-500 μg/L (amount on-column range: 3.2-115 pmol) were analyzed using GC-qMS. The results (³⁷Cl/³⁵Cl ratios) showed satisfying to good precisions with relative standard deviations (n = 5) between 0.4‰ and 2.1‰. However, we found that the achievable precision considerably varies depending on the applied data evaluation scheme, the instrumental settings, and the analyte. A systematic evaluation of these factors allowed us to optimize the GC-qMS technique to determine chlorine isotope ratios of chlorinated organic contaminants. PMID:21612209

  5. Induction of hepatic cytochrome P450 isozymes, benzo(a)pyrene metabolism and DNA binding following exposure to polycyclic aromatic hydrocarbon residues generated during repeated fish fried oil in rats

    SciTech Connect

    Pandey, Manoj K.; Yadav, Sanjay; Parmar, Devendra; Das, Mukul . E-mail: mditrc@rediffmail.com

    2006-06-01

    In the present study the effect of repeated fish fried oil (RFFO) and its extract (RFFE) on hepatic cytochrome P450 (CYP) isozymes, benzo(a)pyrene (BP) metabolism and DNA adduct formation was undertaken. HPLC analysis of RFFO showed the presence of several polycyclic aromatic hydrocarbons. CYP in microsomes from control and RFFO-treated animals showed a peak at 450 nm; however, a shift of 2 nm in the SORET region along with significant induction was observed in microsomes prepared from 3-methylcholanthrene (MC)- and RFFE-treated animals. Activities of hepatic ethoxyresorufin-O-deethylase, methoxyresorufin-O-deethylase, aryl hydrocarbon hydroxylase and erythromycin-N-demethylase were found to be significantly (P < 0.05) induced following exposure of RFFE, whereas none of these enzymes were altered in RFFO-treated group. Immunoblot analysis revealed that RFFE and MC were potent inducers of CYP1A1, 1A1/2 and 3A1 isozymes, where as RFFO showed no change in these protein levels. RT-PCR analysis showed induction of cDNA of CYP1A1 and CYP3A1 by RFFE treatment. Hepatic microsomes prepared from RFFE exposed animals enhanced BP metabolism with a concomitant increase in the relative proportion of BP 7,8-diol. Hepatic microsomes prepared from animals pretreated with RFFE and MC significantly enhanced the binding of [{sup 3}H]-BP to calf thymus DNA. The overall results suggest that exposure to RFFE may induce hepatic CYP isozymes thereby producing enhanced reactive metabolites with a potential to bind with DNA that may result in cancer.

  6. Chlorination-induced genotoxicity in the mussel Perna viridis: assessment by single cell gel electrophoresis (comet) assay.

    PubMed

    Chavan, Pooja; Kumar, Rajesh; Kirubagaran, Ramalingam; Venugopalan, Vayalam P

    2016-08-01

    Mussels are important fouling organisms in the cooling water systems of coastal power plants. Continuous low-dose chlorination (CLDC) is being practiced as an effective method to control mussel biofouling in power plant cooling water systems. CLDC effectively controls mussel fouling by discouraging larval settlement rather than by killing the larvae or adults. Mussels are an integral part of the natural benthic community in the receiving water body where the coolant water is discharged. Hence, from a toxicological point of view, they can serve as both target and non-target organisms. Previous researchers have indicated that chlorine residual, rather than elevated temperature, can be the major stress factor in the effluents released from coastal power plants. However, very little data are available on the sub-lethal effects of low level chlorination on representative benthic fauna. In this study, we used native and transplanted mussels (Perna viridis) to study lethal and sub-lethal effects of chlorination in the cooling water circuit of an operating power plant. Experiments involving comet assay suggested that CLDC can cause DNA damage in treated mussels. However, activation of DNA repair appeared to get initiated after the accrued damage reached a threshold. The results indicate that, at chlorine residual levels observed at the discharge point, exposure to chlorinated effluents is unlikely to cause significant genetic damage to mussels in the recipient water body. PMID:27155389

  7. Chlorine hazard evaluation for the zinc-chlorine electric vehicle battery. Final technical report

    SciTech Connect

    Zalosh, R.G.; Bajpai, S.N.; Short, T.P.; Tsui, R.K.

    1980-04-01

    An evaluation of the hazards associated with conceivable accidental chlorine releases from zinc-chlorine electric vehicle batteries is presented. Since commercial batteries are not yet available, this hazard assessment is based both on theoretical chlorine dispersion models and small-scale and large-scale spill tests with chlorine hydrate. Six spill tests involving chlorine hydrate indicate that the danger zone in which chlorine vapor concentrations intermittently exceed 100 ppM extends at least 23 m directly downwind of a spill onto a warm road surface. Chlorine concentration data from the hydrate spill tests compare favorably with calculations based on a quasi-steady area source dispersion model and empirical estimates of the hydrate decomposition rate. The theoretical dispersion model has been combined with assumed hydrate spill probabilities and current motor vehicle accident statistics in order to project expected chlorine-induced fatality rates. These calculations indicate that expected chlorine fatality rates are several times higher in a city with a warm and calm climate than in a colder and windier city. Calculated chlorine-induced fatality rate projections for various climates are presented as a function of hydrate spill probability in order to illustrate the degree of vehicle/battery crashworthiness required to maintain chlorine-induced fatality rates below current vehicle fatility rates due to fires and asphyxiations.

  8. REACTION PRODUCTS FROM THE CHLORINATION OF SEAWATER

    EPA Science Inventory

    Chemical treatment of natural waters, in particular the use of chlorine as a biocide, modifies the chemistry of these waters in ways that are not fully understood. The research described in this report examined both inorganic and organic reaction products from the chlorination of...

  9. Chlorination products: emerging links with allergic diseases.

    PubMed

    Bernard, A

    2007-01-01

    Exposure of the human population to chlorination products has considerably increased during the 20(th) century especially after the 1960s with the development of public and leisure pools. The present article summarizes current knowledge regarding the human exposure to chlorination products and reviews studies suggesting that these chemicals might be involved in the development or exacerbation of allergic diseases. Populations regularly in contact with chlorination products such as swimmers, lifeguards or workers using chlorine as cleaning or bleaching agent show increased risks of allergic diseases or of respiratory disorders frequently associated with allergy. Experimental evidence suggests that chlorination products promote allergic sensitization by compromising the permeability or the immunoregulatory function of epithelial barriers. These findings led to the chlorine hypothesis proposing that the rise of allergic diseases could result less from the declining exposure to microbial agents (the hygiene hypothesis) than from the increasing and largely uncontrolled exposure to products of chlorination, the most widely used method to achieve hygiene in the developed world. Giving the increasing popularity of water recreational areas, there is an obvious need to assess the effects of chlorine-based oxidants on human health and their possible implication in the epidemic of allergic diseases. PMID:17627515

  10. FATE OF CHROMIUM (III) IN CHLORINATED WATER

    EPA Science Inventory

    The oxidation of trivalent chromium, Cr(III), to the more toxic Cr(VI) in chlorinated water is thermodynamically feasible and was the subject of the study. The study found that free available chlorine (FAC) readily converts Cr(III) to Cr(VI) at a rate that is highly dependent upo...

  11. Chemotaxis of Pseudomonas putida toward chlorinated benzoates

    SciTech Connect

    Harwood, C.S.; Parales, R.E.; Dispensa, M. )

    1990-05-01

    The chlorinated aromatic acids 3-chlorobenzoate and 4-chlorobenzoate are chemoattractants for Pseudomonas putida PRS2000. These compounds are detected by a chromosomally encoded chemotactic response to benzoate which is inducible by {beta}-ketoadipate, and intermediate of benzoate catabolism. Plasmid pAC27, encoding enzymes for 3-chlorobenzoate degradation, does not appear to carry genes for chemotaxis toward chlorinated compounds.

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

    PubMed Central

    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% inactivation after 1 h, while 80 ppm of chlorine and 80 ppm of monochloramine required approximately 90 min for 90% inactivation. The data indicate that C. parvum oocysts are 30 times more resistant to ozone and 14 times more resistant to chlorine dioxide than Giardia cysts exposed to these disinfectants under the same conditions. With the possible exception of ozone, the use of disinfectants alone should not be expected to inactivate C. parvum oocysts in drinking water. PMID:2339894

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

    SciTech Connect

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

    1990-05-01

    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% inactivation after 1 h, while 80 ppm of chlorine and 80 ppm of monochloramine required approximately 90 min for 90% inactivation. The data indicate that C. parvum oocysts are 30 times more resistant to ozone and 14 times more resistant to chlorine dioxide than Giardia cysts exposed to these disinfectants under the same conditions. With the possible exception of ozone, the use of disinfectants alone should not be expected to inactivate C. parvum oocysts in drinking water.

  14. Effects of oil pipeline explosion on ambient particulate matter and their associated polycyclic aromatic hydrocarbons.

    PubMed

    Zhao, Yue; Cao, Lixin; Zhou, Qing; Que, Qiming

    2015-01-01

    Effects of the oil pipeline explosion on PM(2.5)-associated polycyclic aromatic hydrocarbons (PAHs) and their substituted (alkylated, nitrated, oxygenated, hydroxyl and chlorinated) derivatives are assessed near the accident scene of Qingdao, China. Compared with those in TSP-PM(2.5), gaseous phase, burn residue and unburned crude oil, eighty-nine PAHs in PM(2.5) are identified and quantified to investigate the composition, temporal and spatial distribution, and sources. The concentrations of PM(2.5)-associated parent PAHs increase approximately seven times from the non-explosion samples to the explosion samples (mean ± standard deviation: 112 ± 2 vs 764 ± 15 ng/m(3)), while some substituted products (nitro- and oxy-) increase by two orders of magnitude (3117 ± 156 pg/m(3) vs 740 ± 37 ng/m(3)). The toxicity evaluation indicates the BaP equivalent concentrations (based on the US EPA's toxicity factors) in PM(2.5) are much higher than those in the other phases, especially for a long duration after the tragic accident. PMID:25467693

  15. Spatial distribution, temporal variation and risks of parabens and their chlorinated derivatives in urban surface water in Beijing, China.

    PubMed

    Li, Wenhui; Gao, Lihong; Shi, Yali; Wang, Yuan; Liu, Jiemin; Cai, Yaqi

    2016-01-01

    The occurrence and distribution of 13 target compounds, including eight parabens, four chlorinated parabens and p-hydroxybenzoic acid (PHBA), were detected in surface water samples at 35 sampling sites in the Beijing River system, China. The surface water samples were collected from the main rivers and lakes in the urban area monthly from July 2013 to June 2014 (except the frozen period). Laboratory analyses revealed that parabens were ubiquitous in the surface water of Beijing. PHBA was the predominant compound in the surface water samples, with the average concentration of 239ngL(-1), followed by the total amount of chlorinated parabens (average 50.1ng/L) and parabens (average 44.3ng/L). It is noteworthy that octylparaben with longer chain was firstly detected in the surface water. Significant difference was observed for paraben concentrations from different sampling sites, and the highest level of parabens was found in the Xiaotaihou River, which was mainly due to the untreated sewage discharge. Seasonal variation of target compounds in the urban surface water was also studied, and parabens exhibited a different temporal variation from chlorinated derivatives. A combination of factors including high residual chlorine level and water temperature as well as intense ultraviolet radiation might enhance the persistence of chlorinated parabens in chlorinated water during the wet season. Risk assessment showed that parabens and their chlorinated derivatives are not likely to produce biological effects on aquatic ecosystems at current levels in the surface water of Beijing. PMID:26363399

  16. Effects of free and combined chlorine and exposure duration on rainbow trout, channel catfish, and emerald shiners

    SciTech Connect

    Brooks, A.S.; Bartos, J.M.

    1984-11-01

    Laboratory bioassays to determine the acute toxicity of monochloramine, dichloramine, hypochlorous acid, and hypochlorite ion to emerald shiners Notropis atherinoides, channel catfish Ictalurus punctatus, and rainbow trout Salmo gairdneri were conducted. Four exposure regimes typical of chlorination schedules at operating steam electric power plants were used. Fish were exposed for single 15-minute, 30-minute, 120-minute, and 4 x 30-minute periods. Based on median lethal concentrations (LC50s), the nominal solution of hypochlorous acid was the most toxic, followed closely by the solution dominated by dichloramine; nominal monochloramine and hypochlorite ion solutions had a third to a quarter the toxicity of the other two. On the average, emerald shiners were 1.8 times more sensitive than channel catfish and 3.3 times more sensitive than rainbow trout to the four forms of chlorine. The fish were most tolerant of chlorine during short-duration exposures and least tolerant during the continuous 120-minute exposures. The differences in toxicity noted among the chlorine forms suggest that, when chlorination regimes and regulations are established, careful attention should be paid not only to total residual chlorine but to both the chlorine forms and fish species present and the duration of exposure. 24 references, 1 figure, 1 table.

  17. Modeling and testing of reactive contaminant transport in drinking water pipes: chlorine response and implications for online contaminant detection.

    PubMed

    Jeffrey Yang, Y; Goodrich, James A; Clark, Robert M; Li, Sylvana Y

    2008-03-01

    A modified one-dimensional Danckwerts convection-dispersion-reaction (CDR) model is numerically simulated to explain the observed chlorine residual loss for a "slug" of reactive contaminants instantaneously introduced into a drinking water pipe of assumed no or negligible wall demand. In response to longitudinal dispersion, a contaminant propagates into the bulk phase where it reacts with disinfectants in the water. This process generates a U-shaped pattern of chlorine residual loss in a time-series concentration plot. Numerical modeling indicates that the residual loss curve geometry (i.e., slope, depth, and width) is a function of several variables such as axial Péclet number, reaction rate constants, molar fraction of the fast- and slow-reacting contaminants, and the quasi-steady-state chlorine decay inside the "slug" which serves as a boundary condition of the CDR model. Longitudinal dispersion becomes dominant for less reactive contaminants. Pilot-scale pipe flow experiments for a non-reactive sodium fluoride tracer and the fast-reacting aldicarb, a pesticide, were conducted under turbulent flow conditions (Re=9020 and 25,000). Both the experimental results and the CDR modeling are in agreement showing a close relationship among the aldicarb contaminant "slug", chlorine residual loss and its variations, and a concentration increase of chloride as the final reaction product. Based on these findings, the residual loss curve and its geometry are useful tools to identify the presence of a contaminant "slug" and infer its reactive properties in adaptive contaminant detections. PMID:17991507

  18. Chlorine

    MedlinePlus

    ... gas are inhaled. Fluid in the lungs (pulmonary edema) that may be delayed for a few hours ... problems such as fluid in the lungs (pulmonary edema) following the initial exposure. How people can protect ...

  19. Chlorinated aliphatic and aromatic VOC decomposition in air mixture by using electron beam irradiation

    NASA Astrophysics Data System (ADS)

    Chmielewski, A. G.; Sun, Yong-Xia; Bułka, S.; Zimek, Z.

    2004-09-01

    Chlorinated aliphatic and aromatic hydrocarbons, which are emitted from coal power station and waste incinerators, are very harmful to the environment and human health. Recent studies show that chlorinated aliphatic and aromatic hydrocarbons are suspected to be the precursors of dioxin's formation. Dioxin's emission into atmosphere will cause severe environmental problems by ecology contamination. l,4-dichlorobenzene(l,4-DCB) and cis-dichloroethylene( cis-DCE) were chosen as representative chlorinated aromatic and aliphatic compounds, respectively. Their decomposition was investigated by electron beam irradiation. The experiments were carried out "in batch" system. It is found that over 97% cis-DCE is decomposed having an initial concentration of 661 ppm. G-values of cis-DCE decomposition vary from 10 to 28 (molecules/100 eV) for initial concentration of 270-1530 ppm cis-DCE. The decomposition is mainly caused by secondary electron attachment and Cl addition reactions. Comparing with cis-DCE, 1,4-DCB decomposition needs higher absorbed dose. G-value of 1,4-DCB is below 4 molecules/100 eV.

  20. Biodegradation of Chlorinated Solvents: Reactions near DNAPL and Enzyme Function

    SciTech Connect

    McCarty, P. L.; Spormann, Alfred M.; Criddle, Craig, S.

    2003-12-11

    Chlorinated solvents are among the most widespread groundwater contaminants in the country, contamination which is also among the most difficult and expensive for remediation. These solvents are biodegradable in the absence of oxygen, but this biodegradation requires both a food source for the organisms (electron donor) and the presence of chlorinated solvent biodegrading organisms. These two requirements are present naturally at some contamination sites, leading to natural attenuation of the solvents. If one or both requirements are absent, then engineered bioremediation either through addition of an external electron donor or through bioaugmentation with appropriate microorganisms, or both, may be used for site remediation. The most difficult case for cleanup is when a large residual of undissolved chlorinated solvents are present, residing as dense -non-aqueous-phase- liquid ( DNAPL). A major focus of this study was on the potential for biodegradation of the solvents when pre sent as DNAPL where concentrations are very high and potential for toxicity to microorganisms exist. Another focus was on a better understanding of the biological mechanisms involved in chlorinated solvent biodegradation . These studies were directed towards the chlorinated solvents, trichloroethene (TCE), tetrachloroethene or perchloroethene (PCE), and carbon tetrachloride (CT). The potential for biodegradation of TCE and PCE DNAPL was clearly demonstrated in this research. From column soil studies and batch studies we found there to be a clear advantage in focusing efforts at bioremediation near the DNAPL. Here, chlorinated solvent concentrations are the highest, both because of more favorable reaction kinetics and because such high solvent concentrations are toxic to microorganisms, such as methanogens, which compete with dehalogenators for the electron donor. Additionally, biodegradation near a PCE DNAPL results in an enhanced dissolution rate for the chlorinated solvent, by factors of

  1. Combustion of viscous hydrocarbons

    SciTech Connect

    Hayes, M.E.; Hrebenar, K.R.; Murphy, P.L.; Futch, L.E. Jr.; Deal, J.F. III; Bolden, P.L. Jr.

    1987-08-04

    A method is described for utilizing viscous hydrocarbons as combustible pre-atomized fuels, comprising: (A) forming a hydrocarbon-in-water emulsion using an effective amount of a surfactant package comprising at least one water-soluble surfactant, the hydrocarbon-in-water emulsion (1) comprising a hydrocarbon characterized by API gravity of about 20/sup 0/ API or less, viscosity of about 1000 centipoise or greater at 212/sup 0/F., a paraffin content of about 50% by weight or less and, an aromatic content of about 15% by weight or greater, and (2) having a hydrocarbon water ratio from about 60:40 to about 90:10 by volume; and (B) burning the resultant hydrocarbon-in-water emulsion.

  2. Effects of chlorination operating conditions on trihalomethane formation potential in polyaluminum chloride-polymer coagulated effluent.

    PubMed

    Li, Ruihua; Gao, Baoyu; Ma, Defang; Rong, Hongyan; Sun, Shenglei; Wang, Fang; Yue, Qinyan; Wang, Yan

    2015-03-21

    In this study, coagulation performance of polyaluminum chloride (PAC) and PAC-lignin acrylamide (PAC+LAM) in reservoir water treatment was contrastively analyzed. Effects of operating conditions including chlorine dose, contact time and pH on the formation potential of trihalomethanes (THMs) during chlorination in coagulated effluent were also investigated. Comparing with PAC, PAC+LAM achieved higher efficiency in the removal of THMs precursors. TTHM yield in unfiltered water samples (UW) was greater than that of filtered water (FW) due to the residual dissolved organic matter (DOM) in the suspended particles or micro flocs. Meanwhile, operating conditions during chlorination had a significant influence on THMs formation potential. With chlorine dose rising, mass ratio of CHCl3 to TTHM increased, whereas that of CHBr2Cl decreased due to higher Cl2/Br(-) molar ratio. TTHM and CHCl3 levels rose with the increase of pH. Under a given chlorination condition, there was a minor effect of contact time on THM speciation. PMID:25497022

  3. RESIDUAL OXIDANTS REMOVAL FROM COASTAL POWER PLANT COOLING SYSTEM DISCHARGES: FIELD EVALUATION OF SO2 ADDITION SYSTEM

    EPA Science Inventory

    The report gives results of an evaluation of the performance of a dechlorination system that uses SO2 to remove residual oxidants from chlorinated sea water in a power plant cooling system. Samples of unchlorinated, chlorinated, and dechlorinated cooling water were obtained at Pa...

  4. Residual ozone determination by flow injection analysis

    SciTech Connect

    Straka, M.R.; Pacey, G.E.; Gordon, G.

    1984-09-01

    It has been proposed that ozone be used to replace free chlorine for the disinfection of drinking water and waste water. For the use of ozone in this capacity, it would be necessary to have a fast accurate and precise method to analyze for the presence of residuals. An automated method for ozone determination based on the indigo reagent method is presented. This method is based on the advantages of flow injection analysis (FIA) techniques. 19 references, 3 tables, 2 figures.

  5. Chlorinated contaminants in chorio-allantoic membranes from great blue heron eggs at Whidbey Island Naval Air Station.

    PubMed

    Cobb, G P; Norman, D M; Miller, M W; Brewer, L W; Johnston, R K

    1995-01-01

    Chorio-allantoic membranes (CAMs) were collected and analyzed for chlorinated hydrocarbons as part of a wildlife toxicology demonstration project at Naval Air Station (NAS) Whidbey Island, Washington, USA. Concentrations of DDT, DDE, DDD, Aroclor 1254, and Aroclor 1260 were found at concentrations below 0.4 ppm for 13 of 14 samples. The low correlations among DDT and its metabolites in CAMs suggest herons are not being exposed to a consistent source of these compounds. Comparison of chlorinated hydrocarbon data for CAMs from three Puget Sound heron colonies, NAS Whidbey, Samish Island and Dumas Bay, indicates contaminant burdens in herons from NAS Whidbey and Samish Island are significantly lower than burdens in herons from Dumas Bay. PMID:7874465

  6. Formation of dioxins (PCDDs/PCDFs) by dioxin-free fly ash as a catalyst and relation with several chlorine-sources.

    PubMed

    Takasuga, T; Makino, T; Tsubota, K; Takeda, N

    2000-01-01

    Simplified thermal formation experiments have been conducted using dioxin-free fly ash as a catalyst with many kinds of combustible samples such as newspaper, kerosene, paraffin, PE (polyethylene), PP (polypropylene) and PVC. Chlorine sources were PVC, NaCl and HCl. The combustion of samples containing chlorine in the absence of dioxin-free fly ash produced dioxins at a low level although HCl was present in the gas stream. On the other hand, the combustion of samples without chlorine with dioxin-free fly ash increased dioxins formation to a level around 10 times higher than that upon heating dioxin-free fly ash alone. This result is considered to be due to the presence of metal chloride in the fly ash and hydrocarbons in the gas stream. The combustion of samples containing either an organic or inorganic chlorine source or using a HCl stream with dioxin-free fly ash increased dioxin level dramatically. PMID:10739038

  7. Graphene quantum dot as a green and facile sensor for free chlorine in drinking water.

    PubMed

    Dong, Yongqiang; Li, Geli; Zhou, Nana; Wang, Ruixue; Chi, Yuwu; Chen, Guonan

    2012-10-01

    Free chlorine was found to be able to destroy the passivated surface of the graphene quantum dots (GQDs) obtained by pyrolyzing citric acid, resulting in significant quenching of their fluorescence (FL) signal. After optimizing some experimental conditions (including response time, concentration of GQDs, and pH value of solution), a green and facile sensing system has been developed for the detection of free residual chlorine in water based on FL quenching of GQDs. The sensing system exhibits many advantages, such as short response time, excellent selectivity, wide linear response range, and high sensitivity. The linear response range of free chlorine (R(2) = 0.992) was from 0.05 to 10 μM. The detection limit (S/N = 3) was as low as 0.05 μM, which is much lower than that of the most widely used N-N-diethyl-p-phenylenediamine (DPD) colorimetric method. This sensing system was finally used to detect free residual chlorine in local tap water samples. The result agreed well with that by the DPD colorimetric method, suggesting the potential application of this new, green, sensitive, and facile sensing system in drinking water quality monitoring. PMID:22957474

  8. Evaluation of short-term exposure to heated water and chlorine for control of the Asiatic clam (Corbicula fluminea)

    SciTech Connect

    Mattice, J.S.; McLean, R.B.; Burch, M.B.

    1982-01-01

    Based on the need for development of efficient procedures for prevention or control of fouling by the Asiatic clam, Corbicula fluminea, the response of these clams to chlorine in combination with rapid increases in water temperature was examined. Small clams were acclimated to 10 and 25/sup 0/C, and large clams were acclimated to 25/sup 0/C. Experiments with each of these acclimation groups consisted of variables of total residual chlorine concentration (0, 5, 7.5, and 10 mg/L) and test temperature (ambient and 3 test temperatures ranging from 35 to 46/sup 0/C). The periods of exposure to increased temperature and chlorine were 40 and 30 min respectively. Clam mortalities were related to water temperature but not to chlorine exposure. At high temperatures at least 50% of the clams remained open through the entire chlorine exposure period. At higher temperatures all of the clams remained open. Even when clams remained open for the entire 30-min chlorine exposure period, all clams were not killed. However, virtually all clams exposed to 41 to 43/sup 0/C water temperatures were killed whether open or closed during the exposure period. Death due to temperature shock is the logical conclusion from these data. Combined application of heated water and chlorine at the concentrations used is not more effective in killing Corbicula than is heated water alone. Current regulations on the concentration of chlorine in power plant effluents indicate that further studies of control of Corbicula using chlorine offer little likelihood for success. (ERB)

  9. Chlorine-induced cardiopulmonary injury.

    PubMed

    Carlisle, Matthew; Lam, Adam; Svendsen, Erik R; Aggarwal, Saurabh; Matalon, Sadis

    2016-06-01

    Chlorine (Cl2 ) is utilized worldwide for a diverse range of industrial applications, including pulp bleaching, sanitation, and pharmaceutical development. Though Cl2 has widespread use, little is known regarding the mechanisms of toxicity associated with Cl2 exposure, which occurs during industrial accidents or acts of terrorism. Previous instances of Cl2 exposure have led to reported episodes of respiratory distress that result in high morbidity and mortality. Furthermore, studies suggest that acute Cl2 exposure also results in systemic vascular injury and subsequent myocardial contractile dysfunction. Here, we review both lung and cardiac pathology associated with acute Cl2 inhalation and discuss recently published data that suggest that mitochondrial dysfunction underlies the pathogenesis of Cl2 -induced toxicity. Last, we discuss our findings that suggest that upregulation of autophagy protects against Cl2 -induced lung inflammation and can be a potential therapeutic target for ameliorating the toxic effects of Cl2 exposure. PMID:27303906

  10. The occurrence of chlorine in serpentine minerals

    USGS Publications Warehouse

    Miura, Y.; Rucklidge, J.; Nord, G.L., Jr.

    1981-01-01

    Partially serpentinized dunites containing small amounts of Chlorine (< 0.5%) from Dumont, Quebec, and Horoman, Hokkaido, Japan, and one containing less than 0.05% Chlorine from Higashi-Akaishi-Yama, Ehime, Japan have been examined using the electron probe microanalyzer and scanning transmission electron microscope with X-ray analytical capabilities. Chlorine was found together with Si, Mg, Ca and Fe in the serpentine minerals of the Dumont and Hokkaido dunites but not in the Ehime dunite. Chlorine is found associated only with the most finely crystalline facies of the serpentine (grain size less than 10 nm). The Ehime dunite contained no such fine grained serpentine, and was thus effectively chlorine-free, as are the coarser grained serpentines of the other samples. The finegrained chlorine-bearing serpentine also has a much higher concentration of Fe, and can contain smaller amounts of Ca, Ni and Mn than the coarse-grained variety as well as minute awaruite (FeNi3) grains. This fine-grained serpentine probably represents an early stage in the transformation of olivine to serpentine, with chlorine from hydrothermal solutions assisting the necessary chemical changes. The Cl increases the reaction rate by lowering the activation barrier to reaction by the introduction of reaction steps. ?? 1981 Springer-Verlag.

  11. Legionella pneumophila transcriptional response to chlorine treatment.

    PubMed

    Bodet, Charles; Sahr, Tobias; Dupuy, Mathieu; Buchrieser, Carmen; Héchard, Yann

    2012-03-01

    Legionella pneumophila is a ubiquitous environmental microorganism found in freshwater that can cause an acute form of pneumonia known as Legionnaires' disease. Despite widespread use of chlorine to ensure drinking water quality and awareness that L. pneumophila may escape these treatments, little is known about its effects on L. pneumophila. The aim of this study was to investigate the L. pneumophila transcriptional response induced by chlorine treatment. Transcriptome analysis, using DNA arrays, showed that a sublethal dose of chlorine induces a differential expression of 391 genes involved in stress response, virulence, general metabolism, information pathways and transport. Many of the stress response genes were significantly upregulated, whereas a significant number of virulence genes were repressed. In particular, exposure of L. pneumophila to chlorine induced the expression of cellular antioxidant proteins, stress proteins and transcriptional regulators. In addition, glutathione S-transferase specific activity was enhanced following chlorine treatment. Our results clearly indicate that chlorine induces expression of proteins involved in cellular defence mechanisms against oxidative stress that might be involved in adaptation or resistance to chlorine treatment. PMID:22192759

  12. Acanthamoeba castellanii: cellular changes induced by chlorination.

    PubMed

    Mogoa, Emerancienne; Bodet, Charles; Legube, Bernard; Héchard, Yann

    2010-09-01

    Chlorination is a well-known disinfection method, used in water treatment to inactivate various microorganisms, it induces numerous cellular changes. Even though Acanthamoebae are frequently found in water, the cellular changes induced in Acanthamoebae have not been described in the literature. Acanthamoebae are pathogenic amoebae and may provide a reservoir for pathogenic bacteria such as Legionellapneumophila; it is consequently important to understand the response of this amoeba to chlorination, and our study was indeed aimed at examining cellular changes in Acanthamoebae following chlorination. Acanthamoeba trophozoites were treated at various chlorine concentrations (1-5mg/L). A 3-log reduction in Acanthamoebae population was achieved with 5mg/L of free chlorine. Confocal microscopy and flow cytometry experiments indicated that chlorination induced cell permeabilization, size reduction and likely intracellular thiol concentration. Our data show that among the non-cultivable cells some remained impermeabilized (negative staining with propidium iodide), thereby suggesting that these cells might remained viable. A similar state is described in other microorganisms as a VBNC (viable but not cultivable) state. Electron microscopy observations illustrate drastic morphological changes: the pseudopods disappeared and subcellular components, such as mitochondrion, were pronouncedly affected. In conclusion, depending on the concentration used, chlorination leads to many cellular effects on Acanthamoeba that could well arise in cell inactivation. PMID:20034490

  13. Toxicity of chlorine to zebrafish embryos

    PubMed Central

    Kent, Michael L.; Buchner, Cari; Barton, Carrie; Tanguay, Robert L.

    2014-01-01

    Surface disinfection of fertilized fish eggs is widely used in aquaculture to reduce extraovum pathogens that may be released from brood fish during spawning, and this is routinely used in zebrafish (Danio rerio) research laboratories. Most laboratories use approximately 25 – 50 ppm unbuffered chlorine solution for 5 – 10 min. Treatment of embryos with chlorine has significant germicidal effects for many Gram-negative bacteria, viruses, and trophozoite stages of protozoa, it has reduced efficacy against cyst or spore stages of protozoa and certain Mycobacterium spp. Therefore, we evaluated the toxicity of unbufferred and buffered chlorine solution to embryos exposed at 6 or 24 hours post-fertilization (hpf) to determine if higher concentrations can be used for treating zebrafish embryos. Most of our experiments entailed using an outbred line (5D), with both mortality and malformations as endpoints. We found that 6 hpf embryos consistently were more resistant than 24 hpf embryos to the toxic effects of chlorine. Chlorine is more toxic and germicidal at lower pHs, and chlorine causes elevated pH. Consistent with this, we found that unbufferred chlorine solutions (pH ca 8–9) were less toxic at corresponding concentrations than solutions buffered to pH 7. Based on our findings here, we recommend treating 6 hpf embryos for 10 min and 24 hpf for 5 min with unbuffered chlorine solution at 100 ppm. One trial indicated that AB fish, a popular outbred line, are more susceptible to toxicity than 5Ds. This suggests that variability between zebrafish lines occurs, and researchers should evaluate each line or strain under their particular laboratory conditions for selection of the optimum chlorine treatment procedure. PMID:24429474

  14. Chlorination. Training Module 2.300.2.77.

    ERIC Educational Resources Information Center

    Kirkwood Community Coll., Cedar Rapids, IA.

    This document is an instructional module package prepared in objective form for use by an instructor familiar with chlorine, the reasons for chlorination and safe operation and maintenance of gas chlorine, dry calcium hypochlorite and liquid sodium hypochlorite chlorination systems for water supply and wastewater treatment facilities. Included are…

  15. Chlorination of Wastewater, Manual of Practice No. 4.

    ERIC Educational Resources Information Center

    Water Pollution Control Federation, Washington, DC.

    This manual reviews chlorination practices in the treatment and disposal of wastes from the earliest known applications. The application of chlorination for various purposes is described but no attempt has been made to compare chlorination with other methods. Included are chapters on the development and practice of wastewater chlorination,…

  16. Influence of Chlorine Emissions on Ozone Levels in the Troposphere

    EPA Science Inventory

    Chlorine emissions from cooling towers are emitted mainly as hypochlous acid, not as molecular chlorine. Chlorine emissions from cooling towers in electric utilities in the U.S. are estimated to be 4,400 tons per year. Molecular chlorine increases more tropospheric ozone than hyp...

  17. Oxygenated Derivatives of Hydrocarbons

    Technology Transfer Automated Retrieval System (TEKTRAN)

    For the book entitled “Insect Hydrocarbons: Biology, Biochemistry and Chemical Ecology”, this chapter presents a comprehensive review of the occurrence, structure and function of oxygenated derivatives of hydrocarbons. The book chapter focuses on the occurrence, structural identification and functi...

  18. Hydrocarbon Spectral Database

    National Institute of Standards and Technology Data Gateway

    SRD 115 Hydrocarbon Spectral Database (Web, free access)   All of the rotational spectral lines observed and reported in the open literature for 91 hydrocarbon molecules have been tabulated. The isotopic molecular species, assigned quantum numbers, observed frequency, estimated measurement uncertainty and reference are given for each transition reported.

  19. Application of chlorine dioxide for disinfection of student health centers.

    PubMed

    Hsu, Ching-Shan; Lu, Ming-Chun; Huang, Da-Ji

    2012-01-01

    In Taiwan, the immediate health care requirements of students and faculty members are satisfied by on-campus medical service centers. The air quality within these centers should comply with the guidelines laid down by the Taiwan Environmental Protection Agency (EPA). Accordingly, this study performed an experimental investigation into the efficiency of various chlorine dioxide applications in disinfecting a local student health center (SHC). The air quality before and after disinfection were evaluated in terms of the bioaerosol levels of bacteria and fungi. The average background levels of bacteria and fungi before disinfection were found to be 1,142 ± 455.4 CFU/m(3) and 520 ± 442.4 CFU/m(3), respectively. Chlorine dioxide (0.3 mg/m(3)) was applied using three different methods, namely a single, one-off application, multiple applications within a single day, and regular (daily) applications. Among the three disinfection methods, the regular application method was found to yield a high disinfection efficiency for both bacteria and fungi, i.e., 6.5 ± 0.7% and 4.2 ± 0.3%, respectively. The average residual bacteria and fungi levels after regular daily interval disinfection were 318.8 ± 51.5 CFU/m(3) and 254.0 ± 43.8 CFU/m(3), respectively. Therefore, the results suggest that the air quality guidelines prescribed by the Taiwan EPA for SHCs and other healthcare facilities can best be achieved by applying chlorine dioxide at regular (daily) intervals. PMID:21452077

  20. Transfer of chlorine from the environment to agricultural foodstuffs.

    PubMed

    Kashparov, V; Colle, C; Levchuk, S; Yoschenko, V; Svydynuk, N

    2007-01-01

    The factors governing chlorine transfer from Phaeozem and Greyzem soils to various important crop species (foodstuff and forage) were determined in natural conditions in the Kiev region of Ukraine. The stable chlorine concentration ratio (CR) values were the lowest in apple (0.5+/-0.3) and strawberry (2+/-1), higher in vegetables (5+/-3), seeds (15+/-7) and reached a maximum in straw (187+/-90). The average CR values of 36Cl were estimated for the most important crops using all experimental data on 36Cl and stable chlorine transfer into plants from various soils. It was experimentally shown that boiling potatoes in water leads to an equilibrium between 36Cl specific content in the water and moisture in the cooked potato. The 36Cl processing factor (PF) for boiling various foodstuffs is equal to the ratio of water mass in the cooked foodstuff to the total water mass (in the food and the decoction). 36Cl PF for cereal flour can be estimated as 1. The 36Cl processing factor for dairy products is equal to the ratio of residual water mass in the product to initial water mass in milk. At a 36Cl specific activity in soil of 1 Bq kg-1, the estimated annual dietary 36Cl intake into human organism (adult man) is about 10 kBq. Sixty to seventy percent of the above amount will be taken in via milk and dairy products, 7-16% via meat, 14-16% via bread and bakery items and 8-12% via vegetables. The highest annual 36Cl intake, 10.7 kBq, is predicted for 1-year-old children. The expected effective doses from annual 36Cl intake are higher for younger age groups, increasing from 0.008 mSv in adults to 0.12 mSv in 1-year-old children. PMID:17289228