Science.gov

Sample records for biphenyl

  1. Biphenyl

    Integrated Risk Information System (IRIS)

    Biphenyl ; CASRN 92 - 52 - 4 Human health assessment information on a chemical substance is included in IRIS only after a comprehensive review of toxicity data by U.S . EPA health scientists from several program offices , regional offices , and the Office of Research and Development . Sections I ( H

  2. Polychlorinated Biphenyls

    ERIC Educational Resources Information Center

    Peakall, David B.; Lincer, Jeffrey L.

    1970-01-01

    Describes structure, use, analysis, and toxicological properties of polychlorinated biphenyls. Provides data on occurrence and biological magnification in ecosystems. Significance, and synergistic relationships with DDT summarized. (AL)

  3. Method of removing polychlorinated biphenyl from oil

    DOEpatents

    Cook, Gus T.; Holshouser, Stephen K.; Coleman, Richard M.; Harless, Charles E.; Whinnery, III, Walter N.

    1983-01-01

    Polychlorinated biphenyls are removed from oil by extracting the biphenyls into methanol. The mixture of methanol and extracted biphenyls is distilled to separate methanol therefrom, and the methanol is recycled for further use in extraction of biphenyls from oil.

  4. Method of removing polychlorinated biphenyl from oil

    DOEpatents

    Cook, G.T.; Holshouser, S.K.; Coleman, R.M.; Harless, C.E.; Whinnery, W.N. III

    1982-03-17

    Polychlorinated biphenyls are removed from oil by extracting the biphenyls into methanol. The mixture of methanol and extracted biphenyls is distilled to separate methanol therefrom, and the methanol is recycled for further use in extraction of biphenyls from oil.

  5. Polychlorinated biphenyls (PCBs)

    Integrated Risk Information System (IRIS)

    Polychlorinated biphenyls ( PCBs ) ; CASRN 1336 - 36 - 3 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 f

  6. Toxic Substances; Biphenyl; Test Rule

    EPA Pesticide Factsheets

    This rule promulgates EPA’s decision to require manufacturers and processors to test biphenyl (CAS No: 92—52—4) for environmental effects and chemical fate under section 4(a) of the Toxic Substances Control Act (TSCA).

  7. Applications of polychlorinated biphenyls.

    PubMed

    Erickson, Mitchell D; Kaley, Robert G

    2011-02-01

    In the 50 years or so that polychlorinated biphenyls (PCBs) were manufactured in the USA and elsewhere, they were widely used in numerous applications because of their desirable properties. The purpose of this paper is to review and summarize in one place the factual information about the uses of PCBs, as well as to correct some misconceptions that have arisen over the years. The focus is on applications in the USA for which there is ample documentation. However, use patterns were probably similar worldwide. Review. PCBs were used primarily as electrical insulating fluids in capacitors and transformers and also as hydraulic, heat transfer, and lubricating fluids. PCBs were blended with other chemicals as plasticizers and fire retardants and used in a range of products including caulks, adhesives, plastics, and carbonless copy paper. In the USA, PCBs were manufactured from 1929 through mid-1977, although many products remained in service for decades after the manufacture of PCBs was terminated. This article reviews the historic uses of PCBs in the USA and discusses, where possible, the relative sales volumes. Especially with smaller volume, military, and third-party uses, documenting a use and/or differentiating between a commercial use and an experimental test batch is not possible. A major contribution of this paper is to differentiate reported commercial applications of PCBs that can be documented from those which cannot. Undocumented uses may include actual minor uses as well as reported applications that are unlikely ever to have been commercialized.

  8. Chemical Detoxification of Polychlorinated Biphenyls (PCBs).

    DTIC Science & Technology

    The present invention relates to the chemical detoxification of polychlorinated biphenyls by converting them to non-hazardous substances. In...particular, the invention relates to chemically destroying polychlorinated biphenyls on site for decontamination purposes without creating pollution or...hazardous situations. The invention provides a two-step process where polychlorinated biphenyls (PCBs), i.e. biphenyl having 2 to 10 chlorine atoms, are

  9. Carcinogenic effects of polychlorinated biphenyls.

    PubMed

    Faroon, O M; Keith, S; Jones, D; De Rosa, C

    2001-03-01

    As part of its mandate, the Agency for Toxic Substances and Disease Registry (ATSDR) prepares toxicological profiles on hazardous chemicals found at Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) National Priorities List (NPL) sites that have the greatest public health impact. These profiles comprehensively summarize toxicological and environmental information. This article constitutes the release of an important section of the Toxicological profile for polychlorinated biphenyls [ATSDR. 2000: Toxicological profile for polychlorinated biphenyls. Atlanta, GA: US Department of Health and Human Services, Agency for Toxic Substances and Disease Registry.] into the scientific literature. This article focuses on the carcinogenic effects of this group of synthetic organic chemicals (polychlorinated biphenyls) in humans and animals. Information on other health effects, toxicokinetics, mechanisms of toxicity, biomarkers, interactions, chemical and physical properties, potential for human exposure, and regulations and advisories is detailed in the profile.

  10. Current shot noise characteristics in biphenyl diamine and biphenyl dithiol devices

    NASA Astrophysics Data System (ADS)

    kalsoom, Ambreen; Song, Siyu; Li, Guiqin

    2014-09-01

    Current shot noise characteristics, away from their average current, in biphenyl diamine and biphenyl dithiol devices are investigated. The relations among the shot noise and the applied bias, the coupling factors, as well as the alligator clips are revealed. The regular change of the shot noise in biphenyl diamine device and irregular change of the shot noise in biphenyl dithiol device are shown as the coupling strength change from full coupling to weak coupling. It is found that the shot noise suppression in biphenyl diamine device is enhanced at the higher bias. The large differences of the shot noise suppression in the biphenyl dithiol device are revealed.

  11. 40 CFR 721.1790 - Polybrominated biphenyls.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.1790 Polybrominated biphenyls. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substances identified as 1,1′-(Biphenyl, 4,4′-dibromo- (CAS No. 92-86-4);...

  12. Dioxygenation of the Biphenyl Dioxygenation Product

    PubMed Central

    Overwin, Heike; González, Myriam; Méndez, Valentina; Seeger, Michael; Wray, Victor

    2012-01-01

    Two biphenyl dioxygenases (BphAs) were shown to catalyze dioxygenation of biphenyldienediol in the nonoxidized ring to form the respective symmetrical biphenyl-bis-dienediol. This novel metabolite served as a growth substrate for both BphA source strains. Its catabolism through the upper bph pathway of Burkholderia xenovorans LB400 was analyzed. PMID:22504819

  13. Bacterial metabolism of hydroxylated biphenyls.

    PubMed Central

    Higson, F K; Focht, D D

    1989-01-01

    Isolates able to grow on 3- or 4-hydroxybiphenyl (HB) as the sole carbon source were obtained by enrichment culture. The 3-HB degrader Pseudomonas sp. strain FH12 used an NADPH-dependent monooxygenase restricted to 3- and 3,3'-HBs to introduce an ortho-hydroxyl. The 4-HB degrader Pseudomonas sp. strain FH23 used either a mono- or dioxygenase to generate a 2,3-diphenolic substitution pattern which allowed meta-fission of the aromatic ring. By using 3-chlorocatechol to inhibit catechol dioxygenase activity, it was found that 2- and 3-HBs were converted by FH23 to 2,3-HB, whereas biphenyl and 4-HB were attacked by dioxygenation. 4-HB was metabolized to 2,3,4'-trihydroxybiphenyl. Neither organism attacked chlorinated HBs. The degradation of 3- and 4-HBs by these strains is therefore analogous to the metabolism of biphenyl, 2-HB, and naphthalene in the requirement for 2,3-catechol formation. PMID:2729993

  14. Phytoalexins of the Pyrinae: Biphenyls and dibenzofurans

    PubMed Central

    Chizzali, Cornelia

    2012-01-01

    Summary Biphenyls and dibenzofurans are the phytoalexins of the Pyrinae, a subtribe of the plant family Rosaceae. The Pyrinae correspond to the long-recognized Maloideae. Economically valuable species of the Pyrinae are apples and pears. Biphenyls and dibenzofurans are formed de novo in response to infection by bacterial and fungal pathogens. The inducible defense compounds were also produced in cell suspension cultures after treatment with biotic and abiotic elicitors. The antimicrobial activity of the phytoalexins was demonstrated. To date, 10 biphenyls and 17 dibenzofurans were isolated from 14 of the 30 Pyrinae genera. The most widely distributed compounds are the biphenyl aucuparin and the dibenzofuran γ-cotonefuran. The biosynthesis of the two classes of defense compounds is not well understood, despite the importance of the fruit crops. More recent studies have revealed simultaneous accumulation of biphenyls and dibenzofurans, suggesting sequential, rather than the previously proposed parallel, biosynthetic pathways. Elicitor-treated cell cultures of Sorbus aucuparia served as a model system for studying phytoalexin metabolism. The key enzyme that forms the carbon skeleton is biphenyl synthase. The starter substrate for this type-III polyketide synthase is benzoyl-CoA. In apples, biphenyl synthase is encoded by a gene family, members of which are differentially regulated. Metabolism of the phytoalexins may provide new tools for designing disease control strategies for fruit trees of the Pyrinae subtribe. PMID:22563359

  15. Polychlorinated biphenyls in honey bees

    SciTech Connect

    Morse, R.A.; Culliney, T.W.; Gutenmann, W.H.; Littman, C.B.; Lisk, D.J.

    1987-02-01

    Honey bees (Apis mellifera L.) may traverse a radius of several miles from their hives and contact innumerable surfaces during their collection of nectar, pollen, propolis and water. In the process, they may become contaminated with surface constituents which are indicative of the type of environmental pollution in their particular foraging area. Honey has also been analyzed as a possible indicator of heavy metal pollution. Insecticides used in the vicinity of bee hives have been found in bees and honey. It has been recently reported that appreciable concentrations of polychlorinated biphenyls (PCBs) have been found in honey bees sampled throughout Connecticut. In the work reported here, an analytical survey was conducted on PCBs in honey bees, honey, propolis and related samples in several states to learn the extent of contamination and possible sources.

  16. Has the Bacterial Biphenyl Catabolic Pathway Evolved Primarily To Degrade Biphenyl? The Diphenylmethane Case

    PubMed Central

    Pham, Thi Thanh My

    2013-01-01

    In this work, we have compared the ability of Pandoraea pnomenusa B356 and of Burkholderia xenovorans LB400 to metabolize diphenylmethane and benzophenone, two biphenyl analogs in which the phenyl rings are bonded to a single carbon. Both chemicals are of environmental concern. P. pnomenusa B356 grew well on diphenylmethane. On the basis of growth kinetics analyses, diphenylmethane and biphenyl were shown to induce the same catabolic pathway. The profile of metabolites produced during growth of strain B356 on diphenylmethane was the same as the one produced by isolated enzymes of the biphenyl catabolic pathway acting individually or in coupled reactions. The biphenyl dioxygenase oxidizes diphenylmethane to 3-benzylcyclohexa-3,5-diene-1,2-diol very efficiently, and ultimately this metabolite is transformed to phenylacetic acid, which is further metabolized by a lower pathway. Strain B356 was also able to cometabolize benzophenone through its biphenyl pathway, although in this case, this substrate was unable to induce the biphenyl catabolic pathway and the degradation was incomplete, with accumulation of 2-hydroxy-6,7-dioxo-7-phenylheptanoic acid. Unlike strain B356, B. xenovorans LB400 did not grow on diphenylmethane. Its biphenyl pathway enzymes metabolized diphenylmethane, but they poorly metabolize benzophenone. The fact that the biphenyl catabolic pathway of strain B356 metabolized diphenylmethane and benzophenone more efficiently than that of strain LB400 brings us to postulate that in strain B356, this pathway evolved divergently to serve other functions not related to biphenyl degradation. PMID:23749969

  17. Laboratory evaluation of polychlorinated biphenyls encapsulation methods

    EPA Science Inventory

    Effectiveness and limitations of the encapsulation method for reducing polychlorinated biphenyls (PCBs) concentrations in indoor air and contaminated surface have been evaluated in the laboratory study. Ten coating materials such as epoxy and polyurethane coatings, latex paint, a...

  18. Polychlorinated biphenyls in commercial buildings

    SciTech Connect

    Baechler, M.C.; Foley, L.O.; Jarnagin, R.E.

    1990-09-01

    The Bonneville Power Administration (Bonneville) is planning to implement a conservation acquisition program in new and existing commercial buildings. In anticipation of that program, Bonneville is examining the potential environmental effects of conservation measures in commercial buildings. An important conservation measure is the installation of new energy-efficient lighting fixtures. Some of the old lighting fixtures that these new lights will be replacing were manufactured before 1978, when polychlorinated biphenyls (PCBs) were still used in the capacitors of the lighting ballasts. This report focuses on a summary of information about PCBs in fluorescent light fixtures manufactured before 1978. A key issue associated with these PCBs is the potential effect of lamp change-outs on ballast failure. The US Environmental Protection Agency (EPA) speculates that installing energy-efficient lamps in old, PCB-laden ballasts may contribute to ballast failure and PCB leaks, which is addressed in Section 3 of this report. Section 2 discusses applicable standards and regulations; Section 4 describes PCB concentrations in commercial buildings. Sections 5 and 6 discuss cleanup practices and disposal options. 4 tabs.

  19. Developmental neurotoxicity of polybrominated biphenyls.

    PubMed

    Henck, J W; Mattsson, J L; Rezabek, D H; Carlson, C L; Rech, R H

    1994-01-01

    Female F0 generation Sprague-Dawley rats received daily oral doses of 0, 0.2, or 2 mg/kg polybrominated biphenyls (PBB) as fireMaster BP-6 from Day 6 of gestation through Day 24 postpartum. Maternal parameters were assessed, and F1 generation offspring were evaluated for growth and survival, as well as physical and behavioral development. No adverse maternal effects were observed nor were there PBB-related effects on survival of the F1 generation or acquisition of developmental landmarks. Crown-rump length of 0.2 and 2 mg/kg male offspring was significantly less than that of controls and 2 mg/kg male and female offspring gained significantly less weight than did controls for the entire 60-day postnatal observation period. An overall evaluation of behavior by multivariate analysis of variance revealed significant PBB-related effects for acquisition of forward locomotion, cliff avoidance, cage emergence, and open-field activity of male and female offspring from dams administered 2 mg/kg. Delays in acquisition of forward locomotion and suppressed open-field activity were the most prominent effects. These indications of growth retardation and neurobehavioral toxicity occurred at concentrations of PBB in offspring body fat in the range of those which have been reported for highly exposed human subjects with neurological sequelae.

  20. Bioelectrochemical Immunoassay of Polychlorinated Biphenyl

    SciTech Connect

    Lin, Ying-Ying; Liu, Guodong; Wai, Chien M.; Lin, Yuehe

    2008-04-01

    A simple, rapid, and highly sensitive bioelectrochemical immunoassay method based on magnetic beads (MBs) and disposable screen-printed electrodes (SPE) has been developed to detect polychlorinated biphenyls (PCBs). The principle of this bioassay is based on a direct competitive enzyme-linked immunosorbent assay using PCB-antibody-coated MBs and horseradish peroxidase (HRP)-labeled PCB (HRP-PCB). A magnetic process platform was used to mix and shake the samples during the immunoreactions and to separate free and unbound reagents after the liquid-phase competitive immunoreactions among PCB-antibody-coated MBs, PCB analyte, and HRP-PCB. After a complete immunoassay, the HRP tracers attached to MBs were transferred to a substrate solution containing o-aminophenol and hydrogen peroxide for electrochemical detection. The different parameters, including the amount of HRP-PCB conjugates, immunoreaction time, and the concentration of substrate that governs the analytical performance of the immunoassay have been studied in detail and optimized. The detection limit of 5 pg mL-1 was obtained under optimum experimental conditions. The performance of this bioelectrochemical immunoassay was successfully evaluated with untreated river water spiked with PCBs, and the results were validated by commercial PCB enzyme-linked immunosorbent assay kit, indicating that this convenient and sensitive technique offers great promise for decentralized environmental application and trace PCBs monitoring.

  1. Reactive Functionalized Membranes for Polychlorinated Biphenyl Degradation.

    PubMed

    Gui, Minghui; Ormsbee, Lindell E; Bhattacharyya, Dibakar

    2013-08-07

    Membranes have been widely used in water remediation (e.g. desalination and heavy metal removal) because of the ability to control membrane pore size and surface charge. The incorporation of nanomaterials into the membranes provides added benefits through increased reactivity with different functionality. In this study, we report the dechlorination of 2-chlorobiphenyl in the aqueous phase by a reactive membrane system. Fe/Pd bimetallic nanoparticles (NPs) were synthesized (in-situ) within polyacrylic acid (PAA) functionalized polyvinylidene fluoride (PVDF) membranes for degradation of polychlorinated biphenyls (PCBs). Biphenyl formed in the reduction was further oxidized into hydroxylated biphenyls and benzoic acid by an iron-catalyzed hydroxyl radical (OH•) reaction. The formation of magnetite on Fe surface was observed. This combined pathway (reductive/oxidative) could reduce the toxicity of PCBs effectively while eliminating the formation of chlorinated degradation byproducts. The successful manufacturing of full-scale functionalized membranes demonstrates the possibility of applying reactive membranes in practical water treatment.

  2. 40 CFR 721.5713 - Phenol - biphenyl polymer condensate (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Phenol - biphenyl polymer condensate... Specific Chemical Substances § 721.5713 Phenol - biphenyl polymer condensate (generic). (a) Chemical... as a phenol - biphenyl polymer condensate (PMN P-00-1220) is subject to reporting under this...

  3. 40 CFR 721.5713 - Phenol - biphenyl polymer condensate (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Phenol - biphenyl polymer condensate... Specific Chemical Substances § 721.5713 Phenol - biphenyl polymer condensate (generic). (a) Chemical... as a phenol - biphenyl polymer condensate (PMN P-00-1220) is subject to reporting under this...

  4. 40 CFR 721.5713 - Phenol - biphenyl polymer condensate (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Phenol - biphenyl polymer condensate... Specific Chemical Substances § 721.5713 Phenol - biphenyl polymer condensate (generic). (a) Chemical... as a phenol - biphenyl polymer condensate (PMN P-00-1220) is subject to reporting under this section...

  5. 40 CFR 721.5713 - Phenol - biphenyl polymer condensate (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Phenol - biphenyl polymer condensate... Specific Chemical Substances § 721.5713 Phenol - biphenyl polymer condensate (generic). (a) Chemical... as a phenol - biphenyl polymer condensate (PMN P-00-1220) is subject to reporting under this section...

  6. 40 CFR 721.5713 - Phenol - biphenyl polymer condensate (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Phenol - biphenyl polymer condensate... Specific Chemical Substances § 721.5713 Phenol - biphenyl polymer condensate (generic). (a) Chemical... as a phenol - biphenyl polymer condensate (PMN P-00-1220) is subject to reporting under this section...

  7. (eta6-Biphenyl)tricarbonylchromium and mu-(eta6:eta6)-biphenyl-bis(tricarbonylchromium).

    PubMed

    Guzei, Ilia A; Czerwinski, Curtis J

    2004-12-01

    The title compounds, [Cr(C(12)H(10))(CO)(3)] and [Cr(2)(C(12)H(10))(CO)(6)], serve as a fundamental standard of comparison for other mono- and polysubstituted (eta(6)-biphenyl)tricarbonylchromium compounds. (eta(6)-Biphenyl)tricarbonylchromium has a typical piano-stool coordination about the Cr center, and the dihedral angle between the planes of the phenyl rings is 23.55 (5) degrees . The corresponding angle in mu-(eta(6):eta(6))-biphenyl-bis(tricarbonylchromium) is 0 degrees because the molecule occupies a crystallographic inversion center; the Cr atoms reside on opposite sides of the biphenyl ligand. Density functional theory and natural bonding orbital theory analyses were used to scrutinize the geometry of these and closely related compounds to explain important structural features.

  8. Construction of a bioluminescent reporter strain to detect polychlorinated biphenyls

    SciTech Connect

    Layton, A.C.; Muccini, M.; Ghosh, M.M.; Sayler, G.S.

    1998-12-01

    A bioluminescent reporter strain, Ralstonia eutropha ENV307 (pUTK60), was constructed for the detection of polychlorinated biphenyls by inserting the biphenyl promoter upstream of the bioluminescence genes. In the presence of a nonionic surfactant, which enhances the solubility of chlorinated biphenyls, bioluminescence was induced three- to fourfold over background by biphenyl, monochlorinated biphenyls, and Aroclor 1242. The minimum detection limits for these compounds ranged from 0.15 mg/liter for 4-chlorobiphenyl to 1.5 mg/liter for Aroclor 1242.

  9. IRIS Toxicological Review of Biphenyl (Final Report)

    EPA Science Inventory

    EEPA has finalized the Toxicological Review of Biphenyl: in support of the Integrated Risk Information System (IRIS). Now final, this assessment may be used by EPA’s program and regional offices to inform decisions to protect human health.

  10. Degradation of polychlorinated biphenyls by microorganisms

    SciTech Connect

    Yagi, O.; Sudo, R.

    1980-05-01

    The biodegradation of PCB's by microorganisms and the degradation pathway of PCB's are investigated. Experimental methods and materials are described. Only several strains of bacteria, Achromobacter sp., Alcaligenes sp., Acinetobacter sp., Pseudomonas sp., and soil microorganisms were able to decompose PCB's. A possible relationships between the structure and biodegradability of related biphenyl compounds was examined. (5 diagrams, 11 graphs, 18 references, 1 table)

  11. IRIS Toxicological Review of Biphenyl (Final Report)

    EPA Science Inventory

    EEPA has finalized the Toxicological Review of Biphenyl: in support of the Integrated Risk Information System (IRIS). Now final, this assessment may be used by EPA’s program and regional offices to inform decisions to protect human health.

  12. Chronic toxicity of biphenyl to Daphnia magna Straus

    SciTech Connect

    Gersich, F.M.; Bartlett, E.A.; Murphy, P.G.; Milazzo, D.P. )

    1989-09-01

    The US Environmental Protection Agency (EPA) issued a final test rule (1985) for biphenyl on the authority of Section 4(a) of the Toxic Substances Control Act (TSCA). Contained within this rule was the requirement for generating chronic daphnid toxicity data for biphenyl. Biphenyl is used primarily to produce dye carriers, heat-transfer fluids and alkylated biphenyls. The acute toxicity of biphenyl to Daphnia magna has been reported. The 48-hr LC50 values were 4.7 and 2.1 mg/L, respectively. To date, the chronic toxicity of biphenyl to fish and aquatic invertebrates has not been investigated. The objective of this study was to determine the chronic toxicity of biphenyl to D. magna. The daphnid chronic toxicity test is designed to estimate the maximum acceptable toxicant concentration (MATC). The MATC is defined as the concentration falling between the highest concentration showing no effect and the next higher concentration showing a toxic effect when compared to the controls.

  13. Electronic and thermal properties of Biphenyl molecules

    NASA Astrophysics Data System (ADS)

    Medina, F. G.; Ojeda, J. H.; Duque, C. A.; Laroze, D.

    2015-11-01

    Transport properties of a single Biphenyl molecule coupled to two contacts are studied. We characterise this system by a tight-binding Hamiltonian. Based on the non-equilibrium Green's functions technique with a Landauer-Büttiker formalism the transmission probability, current and thermoelectrical power are obtained. We show that the Biphenyl molecule may have semiconductor behavior for certain values of the electrode-molecule-electrode junctions and different values of the angle between the two rings of the molecule. In addition, the density of states (DOS) is calculated to compare the bandwidths with the profile of the transmission probability. DOS allows us to explain the asymmetric shape with respect to the molecule's Fermi energy.

  14. Reactive Functionalized Membranes for Polychlorinated Biphenyl Degradation

    PubMed Central

    Gui, Minghui; Ormsbee, Lindell E.; Bhattacharyya, Dibakar

    2014-01-01

    Membranes have been widely used in water remediation (e.g. desalination and heavy metal removal) because of the ability to control membrane pore size and surface charge. The incorporation of nanomaterials into the membranes provides added benefits through increased reactivity with different functionality. In this study, we report the dechlorination of 2-chlorobiphenyl in the aqueous phase by a reactive membrane system. Fe/Pd bimetallic nanoparticles (NPs) were synthesized (in-situ) within polyacrylic acid (PAA) functionalized polyvinylidene fluoride (PVDF) membranes for degradation of polychlorinated biphenyls (PCBs). Biphenyl formed in the reduction was further oxidized into hydroxylated biphenyls and benzoic acid by an iron-catalyzed hydroxyl radical (OH•) reaction. The formation of magnetite on Fe surface was observed. This combined pathway (reductive/oxidative) could reduce the toxicity of PCBs effectively while eliminating the formation of chlorinated degradation byproducts. The successful manufacturing of full-scale functionalized membranes demonstrates the possibility of applying reactive membranes in practical water treatment. PMID:24954974

  15. IRIS Toxicological Review of Biphenyl (Interagency Science ...

    EPA Pesticide Factsheets

    On September 30, 2011, the draft Toxicological Review of Biphenyl and the charge to external peer reviewers were released for external peer review and public comment. The Toxicological Review and charge were reviewed internally by EPA and by other federal agencies and White House Offices before public release. In the new IRIS process (May 2009), introduced by the EPA Administrator, all written comments on IRIS assessments submitted by other federal agencies and White House Offices will be made publicly available. Accordingly, interagency comments and the interagency science consultation draft of the IRIS Toxicological Review of Biphenyl and the charge to external peer reviewers are posted on this site. EPA is undertaking a new health assessment for biphenyl for the Integrated Risk Information System (IRIS). The outcome of this project will be a Toxicological Review and IRIS and IRIS Summary of biohenyl that will be entered on the IRIS database. IRIS is an EPA database containing Agency scientific positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information to evaluate potential public health risks associated with exposure assessment information to evaluate potential public health risks associated with environmental contaminants. The IRIS database is relied on for the development of risk ass

  16. Thermodynamic properties of biphenyl: Topical report

    SciTech Connect

    Chirico, R. D.; Knipmeyer, S. E.; Nguyen, A.; Steele, W. V.

    1989-06-01

    Ideal-gas thermodynamic properties for biphenyl based on accurate calorimetric measurements were determined between 300 and 700 K, well into the range of typical chemical process temperatures. The calorimetrically derived values provide a firm basis for the prediction of thermodynamic properties for a large family of molecular structures including many substituted biphenyls (such as PCB's) as well as polyphenyls of arbitrary size. Also, results highlighted ambiguities common in the statistical calculation of thermodynamic properties of polycyclic molecules. Critical-property measurement using a differential scanning calorimeter (DSC) showed the commonly accepted assessed value to be in error. This value serves as a ''cornerstone'' in group-contribution critical property estimation schemes, which often are employed by engineers in corresponding-states correlations for the estimation of a great variety of physical properties. Thermodynamically-consistent sublimation vapor pressures were derived to show which of the many literature values are valid; an essential step in the validification of the many reported PCB vapor-pressure measurements, which are key to environmental-impact considerations. Derived Gibbs energies of formation allow the calculation of chemical equilibria in the biphenyl/hydrogen reaction network (published in a companion report; Topical report NIPER-403), which has important ramifications in alternate fuel processing. 85 refs., 11 figs., 16 tabs.

  17. GAS-PHASE OXIDATION PRODUCTS OF BIPHENYL AND POLYCHLORINATED BIPHENYLS (R825377)

    EPA Science Inventory

    Our laboratory recently measured the gas-phase reaction rate constants of
    polychlorinated biphenyls (PCBs) with the hydroxyl radical (OH) and concluded
    that OH reactions are the primary removal pathway of PCBs from the atmosphere.
    With the reaction system previousl...

  18. GAS-PHASE OXIDATION PRODUCTS OF BIPHENYL AND POLYCHLORINATED BIPHENYLS (R825377)

    EPA Science Inventory

    Our laboratory recently measured the gas-phase reaction rate constants of
    polychlorinated biphenyls (PCBs) with the hydroxyl radical (OH) and concluded
    that OH reactions are the primary removal pathway of PCBs from the atmosphere.
    With the reaction system previousl...

  19. Metabolism and metabolites of polychlorinated biphenyls (PCBs)

    PubMed Central

    Grimm, FA; Hu, D; Kania-Korwel, I; Lehmler, HJ; Ludewig, G; Hornbuckle, KC; Duffel, MW; Bergman, A; Robertson, LW

    2015-01-01

    The metabolism of polychlorinated biphenyls (PCBs) is complex and has an impact on toxicity and thereby assessment of PCB risks. A large number of reactive and stable metabolites are formed in the processes of biotransformation in biota in general and in humans in particular. The aim of this document is to provide an overview of PCB metabolism and to identify metabolites of concern and their occurrence. Emphasis is given to mammalian metabolism of PCBs and their hydroxyl, methylsulfonyl, and sulfated metabolites, especially those that persist in human blood. Potential intracellular targets and health risks are also discussed. PMID:25629923

  20. [Male reproductive toxicity of polychlorinated biphenyls].

    PubMed

    Gao, Ming; Wu, Nan-xiang

    2011-05-01

    Polychlorinated biphenyls (PCBs) are a class of persistent organic pollutants with estrogen-like effects that exist widely in the environment, and its male reproductive toxicity is arousing more and more attention. Studies indicate that different types of cells in the testis respond differently to PCBs exposure. This article presents an overview on the toxicity of PCBs to testicular germ cells, Leydig cells, Sertoli cells and male offspring. We suggest that deeper studies focus on the mechanism of PCBs according to the results of investigations on male reproductive epidemiology. An insight into the intercellular junctions of Sertoli cells might produce a breakthrough in the studies of the testicular toxicity of PCBs.

  1. Metabolism and metabolites of polychlorinated biphenyls.

    PubMed

    Grimm, Fabian A; Hu, Dingfei; Kania-Korwel, Izabela; Lehmler, Hans-Joachim; Ludewig, Gabriele; Hornbuckle, Keri C; Duffel, Michael W; Bergman, Åke; Robertson, Larry W

    2015-03-01

    Abstract The metabolism of polychlorinated biphenyls (PCBs) is complex and has an impact on toxicity, and thereby on the assessment of PCB risks. A large number of reactive and stable metabolites are formed in the processes of biotransformation in biota in general, and in humans in particular. The aim of this document is to provide an overview of PCB metabolism, and to identify the metabolites of concern and their occurrence. Emphasis is given to mammalian metabolism of PCBs and their hydroxyl, methylsulfonyl, and sulfated metabolites, especially those that persist in human blood. Potential intracellular targets and health risks are also discussed.

  2. Human Health Effects of Biphenyl: Key Findings and Scientific Issues

    PubMed Central

    Li, Zheng; Hogan, Karen A.; Cai, Christine; Rieth, Susan

    2015-01-01

    Background: In support of the Integrated Risk Information System (IRIS), the U.S. Environmental Protection Agency (EPA) has evaluated the human health hazards of biphenyl exposure. Objectives: We review key findings and scientific issues regarding expected human health effects of biphenyl. Methods: Scientific literature from 1926 through September 2012 was critically evaluated to identify potential human health hazards associated with biphenyl exposure. Key issues related to the carcinogenicity and noncancer health hazards of biphenyl were examined based on evidence from experimental animal bioassays and mechanistic studies. Discussion: Systematic consideration of experimental animal studies of oral biphenyl exposure took into account the variety of study designs (e.g., study sizes, exposure levels, and exposure durations) to reconcile differing reported results. The available mechanistic and toxicokinetic evidence supports the hypothesis that male rat urinary bladder tumors arise through urinary bladder calculi formation but is insufficient to hypothesize a mode of action for liver tumors in female mice. Biphenyl and its metabolites may induce genetic damage, but a role for genotoxicity in biphenyl-induced carcinogenicity has not been established. Conclusions: The available health effects data for biphenyl provides suggestive evidence for carcinogenicity in humans, based on increased incidences of male rat urinary bladder tumors at high exposure levels and on female mouse liver tumors. Kidney toxicity is also a potential human health hazard of biphenyl exposure. Citation: Li Z, Hogan KA, Cai C, Rieth S. 2016. Human health effects of biphenyl: key findings and scientific issues. Environ Health Perspect 124:703–712; http://dx.doi.org/10.1289/ehp.1509730 PMID:26529796

  3. Endometriosis among Women Exposed to Polybrominated Biphenyls

    PubMed Central

    Hoffman, Caroline S.; Small, Chanley M.; Blanck, Heidi Michels; Tolbert, Paige; Rubin, Carol; Marcus, Michele

    2007-01-01

    Purpose We examined the association between endometriosis and exposure to polybrominated biphenyls (PBBs) and polychlorinated biphenyls (PCBs) among women inadvertently exposed to PBBs in 1973. Methods Serum PBB and PCB were measured in the late 1970s. Women self-reported endometriosis at interview in 1997. We constructed Cox models to estimate the relative incidence of endometriosis in relation to PBB and PCB levels. Results Seventy-nine of 943 women (9%) reported endometriosis. Compared to women with low PBB exposure (≤ 1 parts per billion [ppb]), women with moderate PBB (1–4 ppb) (hazard ratio [HR] = 0.72; 95% confidence interval [CI], 0.39–1.31) and high PBB (≥ 4 ppb) (HR = 0.90; 95% CI, 0.51–1.59) exposure did not have increased incidence of endometriosis. Increased incidence of endometriosis was suggested among women exposed to moderate PCB (5–8 ppb) (HR = 1.67; 95% CI, 0.91–3.10) and high PCB (≥ 8 ppb) (HR = 1.68; 95% CI, 0.95–2.98) levels compared to low PCB exposure (≤ 5 ppb). Conclusions Our study does not support an association between PBB exposure and endometriosis. Findings for serum PCB level are consistent with an emerging body of literature suggesting an association between PCB exposure and endometriosis. PMID:17448678

  4. Process for removing polychlorinated biphenyls from soil

    DOEpatents

    Hancher, C.W.; Saunders, M.B.; Googin, J.M.

    1984-11-16

    The present invention relates to a method of removing polychlorinated biphenyls from soil. The polychlorinated biphenyls are extracted from the soil by employing a liquid organic solvent dispersed in water in the ratio of about 1:3 to 3:1. The organic solvent includes such materials as short-chain hydrocarbons including kerosene or gasoline which are immiscible with water and are nonpolar. The organic solvent has a greater affinity for the PCB's than the soil so as to extract the PCB's from the soil upon contact. The organic solvent phase is separated from the suspended soil and water phase and distilled for permitting the recycle of the organic solvent phase and the concentration of the PCB's in the remaining organic phase. The present process can be satisfactorily practiced with soil containing 10 to 20% petroleum-based oils and organic fluids such as used in transformers and cutting fluids, coolants and the like which contain PCB's. The subject method provides for the removal of a sufficient concentration of PCB's from the soil to provide the soil with a level of PCB's within the guidelines of the Environmental Protection Agency.

  5. Oxidation of polychlorinated biphenyls by Pseudomonas sp. strain LB400 and Pseudomonas pseudoalcaligenes KF707.

    PubMed Central

    Gibson, D T; Cruden, D L; Haddock, J D; Zylstra, G J; Brand, J M

    1993-01-01

    Biphenyl-grown cells and cell extracts prepared from biphenyl-grown cells of Pseudomonas sp. strain LB400 oxidize a much wider range of chlorinated biphenyls than do analogous preparations from Pseudomonas pseudoalcaligenes KF707. These results are attributed to differences in the substrate specificity of the biphenyl 2,3-dioxygenases from both organisms. PMID:8331086

  6. Final report for Tank 100 Sump sludge (KON332) for polychlorinated biphenyl`s (PCB)

    SciTech Connect

    Fuller, R.K.

    1998-07-30

    Final Report for Tank 100 Sump Sludge (KON332) for Polychlorinated Biphenyl`s (PCB) Sample Receipt Sample KON332 was received from Tank 100-Sump (WESF) on May 18, 1998. The laboratory number issued for this sample is S98BOO0207 as shown on the Request for Sample Analysis (RSA) form (Attachment 4). The sample breakdown diagram (Attachment 3) provides a cross-reference of customer sample identification to the laboratory identification number. Attachment 4 provides copies of the Request for Sample Analysis (RSA) and Chain of Custody (COC) forms. The sample was received in the laboratory in a 125-ml polybottle. Breakdown and subsampling was performed on June 6, 1998. PCB analysis was performed on the wet sludge. A discussion of the results is presented in Attachment 2. The 222-S extraction bench sheets are presented in Attachment 5. The PCB raw data are presented in Attachment 6.

  7. Sphingobium fuliginis HC3: A Novel and Robust Isolated Biphenyl- and Polychlorinated Biphenyls-Degrading Bacterium without Dead-End Intermediates Accumulation

    PubMed Central

    Hu, Jinxing; Qian, Mingrong; Zhang, Qian; Cui, Jinglan; Yu, Chunna; Su, Xiaomei; Shen, Chaofeng; Hashmi, Muhammad Z.; Shi, Jiyan

    2015-01-01

    Biphenyl and polychlorinated biphenyls (PCBs) are typical environmental pollutants. However, these pollutants are hard to be totally mineralized by environmental microorganisms. One reason for this is the accumulation of dead-end intermediates during biphenyl and PCBs biodegradation, especially benzoate and chlorobenzoates (CBAs). Until now, only a few microorganisms have been reported to have the ability to completely mineralize biphenyl and PCBs. In this research, a novel bacterium HC3, which could degrade biphenyl and PCBs without dead-end intermediates accumulation, was isolated from PCBs-contaminated soil and identified as Sphingobium fuliginis. Benzoate and 3-chlorobenzoate (3-CBA) transformed from biphenyl and 3-chlorobiphenyl (3-CB) could be rapidly degraded by HC3. This strain has strong degradation ability of biphenyl, lower chlorinated (mono-, di- and tri-) PCBs as well as mono-CBAs, and the biphenyl/PCBs catabolic genes of HC3 are cloned on its plasmid. It could degrade 80.7% of 100 mg L −1 biphenyl within 24 h and its biphenyl degradation ability could be enhanced by adding readily available carbon sources such as tryptone and yeast extract. As far as we know, HC3 is the first reported that can degrade biphenyl and 3-CB without accumulation of benzoate and 3-CBA in the genus Sphingobium, which indicates the bacterium has the potential to totally mineralize biphenyl/PCBs and might be a good candidate for restoring biphenyl/PCBs-polluted environments. PMID:25875180

  8. Adaptive responses and cellular behaviour of biphenyl-degrading bacteria toward polychlorinated biphenyls.

    PubMed

    Chávez, Francisco P; Gordillo, Felipe; Jerez, Carlos A

    2006-01-01

    Polychlorinated biphenyls (PCBs) are one of the most widely distributed classes of chlorinated chemicals in the environment. For cleanup of large areas of PCB-contaminated environments, bioremediation seems to be a promising approach. However, the multitude of PCB congeners, their low bioavailability and high toxicity are important factors that affect the cleanup progression. Elucidating how the PCB-degrading microorganisms involved in the process adapt to and deal with the stressing conditions caused by this class of compounds may help to improve the bioremediation process. Also specific physiological characteristics of biphenyl-utilizing bacteria involved in the degradation of PCBs may enhance their availability to these compounds and therefore contribute to a better microbial mineralization. This review will focus in the stress responses caused in aerobic biphenyl-utilizing bacteria by PCBs and its metabolic intermediates and will also analyze bacterial properties such as motility and chemotaxis, adherence to solid surfaces, biosurfactant production and biofilm development, all properties found to enhance bacteria-pollutant interaction.

  9. PRACTICAL APPROACHES TO REMEDIATION OF POLYCHLORINATED BIPHENYLS IN SEDIMENTS

    EPA Science Inventory

    Polychlorinated biphenyls (PCBs) are one group of persistent organic pollutants (POPs) of international concern because of global distribution, persistence, and toxicity. Removal of these compounds from the environment presents a very tough challenge because they are highly hydro...

  10. PRACTICAL APPROACHES TO REMEDIATION OF POLYCHLORINATED BIPHENYLS IN SEDIMENTS

    EPA Science Inventory

    Polychlorinated biphenyls (PCBs) are one group of persistent organic pollutants (POPs) of international concern because of global distribution, persistence, and toxicity. Removal of these compounds from the environment presents a very tough challenge because they are highly hydro...

  11. IRIS Toxicological Review of Biphenyl (External Review Draft) (September 2011)

    EPA Science Inventory

    EPA is conducting a peer review of the scientific basis supporting the human health hazard and dose-response assessment of biphenyl that will appear in the Integrated Risk Information System (IRIS) database.

  12. IRIS Toxicological Review of Biphenyl (External Review Draft) (September 2011)

    EPA Science Inventory

    EPA is conducting a peer review of the scientific basis supporting the human health hazard and dose-response assessment of biphenyl that will appear in the Integrated Risk Information System (IRIS) database.

  13. Toxicity of polybrominated biphenyls (PBBs) in Domestic and laboratory animals.

    PubMed Central

    Damstra, T; Jurgelski, W; Posner, H S; Vouk, V B; Bernheim, N J; Guthrie, J; Luster, M; Falk, H L

    1982-01-01

    The composition, environmental fate, and effects of the polybrominated biphenyls (Firemaster BP-6 or FF-1) involved in the accidental contamination of cattle feed in Michigan in 1973 are reviewed. Toxic effects referred to in this report are limited to those occurring in domestic and laboratory animals and include general toxicity, neurobehavioral toxicity, immunotoxicity, reproductive toxicity, mutagenicity and carcinogenicity. The absorption, distribution, biotransformation and elimination of these polybrominated biphenyls are discussed along with the interactions with other chemicals and drugs. PMID:6282577

  14. NUCLEOTIDE SEQUENCING AND TRANSCRIPTIONAL MAPPING OF THE GENES ENCODING BIPHENYL DIOXYGENASE, A MULTICOM- PONENT POLYCHLORINATED-BIPHENYL-DEGRADING ENZYME IN PSEUDOMONAS STRAIN LB400

    EPA Science Inventory

    The DNA region encoding biphenyl dioxygenase, the first enzyme in the biphenyl-polychlorinated biphenyl degradation pathway of Pseudomonas species strain LB400, was sequenced. Six open reading frames were identified, four of which are homologous to the components of toluene dioxy...

  15. NUCLEOTIDE SEQUENCING AND TRANSCRIPTIONAL MAPPING OF THE GENES ENCODING BIPHENYL DIOXYGENASE, A MULTICOM- PONENT POLYCHLORINATED-BIPHENYL-DEGRADING ENZYME IN PSEUDOMONAS STRAIN LB400

    EPA Science Inventory

    The DNA region encoding biphenyl dioxygenase, the first enzyme in the biphenyl-polychlorinated biphenyl degradation pathway of Pseudomonas species strain LB400, was sequenced. Six open reading frames were identified, four of which are homologous to the components of toluene dioxy...

  16. Complete Genome Sequence of the Polychlorinated Biphenyl-Degrading Bacterium Pseudomonas putida KF715 (NBRC 110667) Isolated from Biphenyl-Contaminated Soil

    PubMed Central

    Yamazoe, Atsushi; Hosoyama, Akira; Kimura, Nobutada; Hirose, Jun; Watanabe, Takahito; Fujihara, Hidehiko; Futagami, Taiki; Goto, Masatoshi; Furukawa, Kensuke

    2017-01-01

    ABSTRACT Pseudomonas putida KF715 (NBRC 110667) utilizes biphenyl as a sole source of carbon and degrades polychlorinated biphenyls (PCBs). Here, we report a complete genome sequence of the KF715 strain, which comprises a circular chromosome and four plasmids. Biphenyl catabolic genes were located on the largest plasmid, pKF715A. PMID:28209826

  17. Structural Characterization of Pandoraea pnomenusa B-356 Biphenyl Dioxygenase Reveals Features of Potent Polychlorinated Biphenyl-Degrading Enzymes

    PubMed Central

    Chakko, Mathew N.; Sinha, Sangita C.; Powlowski, Justin B.; Eltis, Lindsay D.; Bolin, Jeffrey T.

    2013-01-01

    The oxidative degradation of biphenyl and polychlorinated biphenyls (PCBs) is initiated in Pandoraea pnomenusa B-356 by biphenyl dioxygenase (BPDOB356). BPDOB356, a heterohexameric (αβ)3 Rieske oxygenase (RO), catalyzes the insertion of dioxygen with stereo- and regioselectivity at the 2,3-carbons of biphenyl, and can transform a broad spectrum of PCB congeners. Here we present the X-ray crystal structures of BPDOB356 with and without its substrate biphenyl 1.6-Å resolution for both structures. In both cases, the Fe(II) has five ligands in a square pyramidal configuration: H233 Nε2, H239 Nε2, D386 Oδ1 and Oδ2, and a single water molecule. Analysis of the active sites of BPDOB356 and related ROs revealed structural features that likely contribute to the superior PCB-degrading ability of certain BPDOs. First, the active site cavity readily accommodates biphenyl with minimal conformational rearrangement. Second, M231 was predicted to sterically interfere with binding of some PCBs, and substitution of this residue yielded variants that transform 2,2′-dichlorobiphenyl more effectively. Third, in addition to the volume and shape of the active site, residues at the active site entrance also apparently influence substrate preference. Finally, comparison of the conformation of the active site entrance loop among ROs provides a basis for a structure-based classification consistent with a phylogeny derived from amino acid sequence alignments. PMID:23308114

  18. Occupational exposure to polychlorinated biphenyls in electrical workers. I. Environmental and blood polychlorinated biphenyls concentrations.

    PubMed Central

    Maroni, M; Colombi, A; Cantoni, S; Ferioli, E; Foa, V

    1981-01-01

    Industrial exposure to polychlorinated biphenyls (PCBs) and internal dose were investigated in 80 worker exposed for many years to PCB mixtures with a 42% chlorine content (Pyralene 3010 and Apirolio). PCBs were determined by liquid gas chromatography on samples taken from workroom air, workroom surfaces and tools, the palms of the hand, and the blood of the workers. In the workroom air samples, PCB concentrations ranged from 48 to 275 micrograms/m3. All tested surfaces and tools were heavily contaminated, with a range from 0.2 to 159 micrograms PCBs per cm2 of surface. Considerable amounts of PCBs were detected on the palms of the hands of the workers (2-28 microgram/cm2 of skin surface). In blood, total PCB concentrations from 88 to 1319 micrograms/kg were observed: comparing the blood concentrations of low and high chlorine content biphenyls, a significant difference was found for the low-chlorinated biphenyl concentrations between workers currently exposed and workers exposed only in the past. In groups of workers who were homogeneous as regards work area and job, the PCB concentrations in the blood were closely correlated with the length of actual occupational exposure to these compounds. These findings led to the conclusion that absorption of PCBs in these workers had occurred mainly through the skin, therefore industrial preventive surveillance must take this route of exposure into account. Since blood PCB concentrations appear to be correlated with the length of exposure, PCB determination on whole blood may be used to monitor industrial and environmental exposure to PCBs. PMID:6781529

  19. Polychlorinated Biphenyls and links to Cardiovascular Disease

    PubMed Central

    Perkins, Jordan T.; Petriello, Michael C.; Newsome, Bradley J.; Hennig, Bernhard

    2015-01-01

    The pathology of cardiovascular disease is multi-faceted, with links to many modifiable and non-modifiable risk factors. Epidemiological evidence now implicates exposure to persistent organic pollutants, such as polychlorinated biphenyls (PCBs), with an increased risk of developing diabetes, hypertension, and obesity; all of which are clinically relevant to the onset and progression of cardiovascular disease. PCBs exert their cardiovascular toxicity either directly or indirectly via multiple mechanisms, which are highly dependent on the type and concentration of PCBs present. However, many PCBs may modulate cellular signaling pathways leading to common detrimental outcomes including induction of chronic oxidative stress, inflammation, and endocrine disruption. With the abundance of potential toxic pollutants increasing globally, it is critical to identify sensible means of decreasing associated disease risks. Emerging evidence now implicates a protective role of lifestyle modifications such as increased exercise and/or nutritional modulation via anti-inflammatory foods, which may help to decrease the vascular toxicity of PCBs. This review will outline the current state of knowledge linking coplanar and non-coplanar PCBs to cardiovascular disease and describe the possible molecular mechanism of this association. PMID:25877901

  20. Inadvertent Polychlorinated Biphenyls in Commercial Paint Pigments†

    PubMed Central

    2009-01-01

    A polychlorinated biphenyl (PCB) that was not produced as part of the Aroclor mixtures banned in the 1980s was recently reported in air samples collected in Chicago, Philadelphia, the Arctic, and several sites around the Great Lakes. In Chicago, the congener 3,3′-dichlorobiphenyl or PCB11 was found to be the fifth most concentrated congener and ubiquitous throughout the city. The congener exhibited strong seasonal concentration trends that suggest volatilization of this compound from common outdoor surfaces. Due to these findings and also the compound’s presence in waters that received waste from paint manufacturing facilities, we hypothesized that PCB11 may be present in current commercial paint. In this study we measured PCBs in paint sold on the current retail market. We tested 33 commercial paint pigments purchased from three local paint stores. The pigment samples were analyzed for all 209 PCB congeners using gas chromatography with tandem mass spectrometry (GC-MS/MS). More than 50 PCB congeners including several dioxin-like PCBs were detected, and the PCB profiles varied due to different types of pigments and different manufacturing processes. PCB congeners were detected in azo and phthalocyanine pigments which are commonly used in paint but also in inks, textiles, paper, cosmetics, leather, plastics, food and other materials. Our findings suggest several possible mechanisms for the inadvertent production of specific PCB congeners during the manufacturing of paint pigments. PMID:19957996

  1. Chamber study of polychlorinated biphenyl {PCB} emissions ...

    EPA Pesticide Factsheets

    The sorption of airborne polychlorinated biphenyls (PCBs) by twenty building materials and their subsequent re-emission (desorption) from concrete were investigated using two 53-L environmental chambers connected in series with a field-collected caulk in the source chamber serving as a stable source of PCBs and building materials in the test chamber. During the tests, the PCB concentrations in the outlet air of the test chamber were monitored and the building materials were removed from the test chamber at different times to determine their PCB content. Among the materials tested, a petroleum-based paint, a latex paint, and a certain type of carpet were among the strongest sinks. Solvent-free epoxy coating, certain types of flooring materials, and brick were among the weakest sinks. For a given sink material, PCB congeners with lower vapor pressures were sorbed in larger quantities. Rough estimates of the partition and diffusion coefficients were obtained by applying a sink model to the data acquired from the chamber studies. A desorption test with the concrete panels showed that re-emission is a slow process, suggesting that PCB sinks, e.g. concrete, can release PCBs into the air for a prolonged period of time (years or decades). This study could fill some of the data gaps associated with the characterization of PCB sinks in contaminated buildings. This paper summarizes the laboratory research results for PCB transport from primary sources to PCB sinks, includ

  2. Polychlorinated Biphenyls (PCBs), Organochlorine Pesticides, and Neurodevelopment

    PubMed Central

    Korrick, Susan A.; Sagiv, Sharon K.

    2013-01-01

    Purpose of review Although environmental levels of polychlorinated biphenyls (PCBs) and certain organochlorine pesticides – hexachlorobenzene (HCB), dichlorodiphenyl trichloroethane (DDT) and its primary metabolite, dichlorodiphenyl dicloroethene (DDE) – are generally on the decline, early-life exposures to these prevalent contaminants continue. This review will describe current understanding of the potential neurodevelopmental consequences of low-level exposures to these contaminants. Findings Animal models suggest that early-life exposures to PCBs, DDT/DDE, or HCB are associated with decreased cognitive or behavioral function in later development. However, despite almost 30 years of research, results of human studies are inconsistent regarding the nature of the observed effects and their persistence over time. Overall, epidemiologic studies support modest associations of primarily prenatal PCB exposures with differences in neuromotor development, decrements in cognition, and behavioral deficits, particularly regarding attention and impulse control. There are limited published human data regarding potential neurodevelopmental toxicities of early-life exposures to DDT/DDE and HCB. Summary Exposures to PCBs, DDT/DDE and HCB are likely detrimental to neurodevelopment. Effective control of exposure is complicated by variable exposure sources and variable contaminant levels in food, particularly fish, for which it is important to balance the risk of contaminants with nutritional benefits. PMID:18332718

  3. Inadvertent polychlorinated biphenyls in commercial paint pigments.

    PubMed

    Hu, Dingfei; Hornbuckle, Keri C

    2010-04-15

    A polychlorinated biphenyl (PCB) that was not produced as part of the Aroclor mixtures banned in the 1980s was recently reported in air samples collected in Chicago, Philadelphia, the Arctic, and several sites around the Great Lakes. In Chicago, the congener 3,3'-dichlorobiphenyl or PCB11 was found to be the fifth most concentrated congener and ubiquitous throughout the city. The congener exhibited strong seasonal concentration trends that suggest volatilization of this compound from common outdoor surfaces. Due to these findings and also the compound's presence in waters that received waste from paint manufacturing facilities, we hypothesized that PCB11 may be present in current commercial paint. In this study we measured PCBs in paint sold on the current retail market. We tested 33 commercial paint pigments purchased from three local paint stores. The pigment samples were analyzed for all 209 PCB congeners using gas chromatography with tandem mass spectrometry (GC-MS/MS). More than 50 PCB congeners including several dioxin-like PCBs were detected, and the PCB profiles varied due to different types of pigments and different manufacturing processes. PCB congeners were detected in azo and phthalocyanine pigments which are commonly used in paint but also in inks, textiles, paper, cosmetics, leather, plastics, food and other materials. Our findings suggest several possible mechanisms for the inadvertent production of specific PCB congeners during the manufacturing of paint pigments.

  4. Chamber study of polychlorinated biphenyl (PCB) emissions ...

    EPA Pesticide Factsheets

    The sorption of airborne polychlorinated biphenyls (PCBs) by twenty building materials and their subsequent re-emission (desorption) from concrete were investigated using two 53-L environmental chambers connected in series with a field-collected caulk in the source chamber serving as a stable source of PCBs and building materials in the test chamber. During the tests, the PCB concentrations in the outlet air of the test chamber were monitored and the building materials were removed from the test chamber at different times to determine their PCB content. Among the materials tested, a petroleum-based paint, a latex paint, and a certain type of carpet were among the strongest sinks. Solvent-free epoxy coating, certain types of flooring materials, and brick were among the weakest sinks. For a given sink material, PCB congeners with lower vapor pressures were sorbed in larger quantities. Rough estimates of the partition and diffusion coefficients were obtained by applying a sink model to the data acquired from the chamber studies. A desorption test with the concrete panels showed that re-emission is a slow process, suggesting that PCB sinks, e.g. concrete, can release PCBs into the air for a prolonged period of time (years or decades). This study could fill some of the data gaps associated with the characterization of PCB sinks in contaminated buildings. This paper summarizes the laboratory research results for PCB transport from primary sources to PCB sinks, includ

  5. Polychlorinated biphenyls and links to cardiovascular disease.

    PubMed

    Perkins, Jordan T; Petriello, Michael C; Newsome, Bradley J; Hennig, Bernhard

    2016-02-01

    The pathology of cardiovascular disease is multi-faceted, with links to many modifiable and non-modifiable risk factors. Epidemiological evidence now implicates exposure to persistent organic pollutants, such as polychlorinated biphenyls (PCBs), with an increased risk of developing diabetes, hypertension, and obesity; all of which are clinically relevant to the onset and progression of cardiovascular disease. PCBs exert their cardiovascular toxicity either directly or indirectly via multiple mechanisms, which are highly dependent on the type and concentration of PCBs present. However, many PCBs may modulate cellular signaling pathways leading to common detrimental outcomes including induction of chronic oxidative stress, inflammation, and endocrine disruption. With the abundance of potential toxic pollutants increasing globally, it is critical to identify sensible means of decreasing associated disease risks. Emerging evidence now implicates a protective role of lifestyle modifications such as increased exercise and/or nutritional modulation via anti-inflammatory foods, which may help to decrease the vascular toxicity of PCBs. This review will outline the current state of knowledge linking coplanar and non-coplanar PCBs to cardiovascular disease and describe the possible molecular mechanism of this association.

  6. Octanol/air partitioning of polychlorinated biphenyls

    SciTech Connect

    Komp, P.; McLachlan, M.S.

    1997-12-01

    The partitioning of 16 polychlorinated biphenyls (PCBs) between air and 1-octanol was investigated using a fugacity meter. The measurements were conducted over an environmentally relevant temperature range (10--43 C). For a given congener the measured 1-octanol/air partition coefficient K{sub OA} was exponentially proportional to the reciprocal temperature. The enthalpy of phase change (octanol to air) {Delta}H{sub OA} ranged from 71 to 93 kJ/mol. Up to log K{sub OA} values of 9.37 (corresponding to 2,2{prime},3,4{prime},5{prime},6-hexachlorobiphenyl), the enthalpy of phase change was similar to the enthalpy of vaporization of the subcooled liquid PCB. For the less volatile congeners (log K{sub OA} > 9.37), the enthalpies of vaporization exceeded the enthalpies of phase change, the difference increasing with increasing log K{sub OA}. Solubilities of the PCBs in 1-octanol were calculated from the data, and the results were in excellent agreement with octanol solubilities calculated using the OCTASOL fragment method. A very good correlation between the measured octanol/air partition coefficients and values calculated from octanol/water and air/water partition coefficients was obtained. This yielded a method to estimate reliably the octanol/air partitioning of all PCB congeners.

  7. Tris(biphenyl-4-yl)arsane

    PubMed Central

    Shawkataly, Omar bin; Khan, Imthyaz Ahmed; Sirat, Siti Syaida; Yeap, Chin Sing; Fun, Hoong-Kun

    2011-01-01

    The asymmetric unit of title compound, C36H27As, contains two crystallographically independent mol­ecules, A and B, with similar conformations. The two phenyl rings of each biphenyl unit are twisted slightly away from each other with dihedral angles of 6.0 (2), 27.7 (3) and 33.4 (2)° in mol­ecule A and 5.7 (3), 27.5 (2) and 33.0 (2)° in mol­ecule B. The As-bonded phenyl rings make dihedral angles of 54.9 (2), 76.0 (2) and 88.2 (2),° with each other in mol­ecule A, and 60.3 (2), 78.1 (2) and 79.5 (2)° in mol­ecule B. In the crystal, the mol­ecules are stacked down the b axis. Weak inter­molecular C—H⋯π inter­actions stabilize the crystal structure. The crystal studied was a racemic twin, the refined ratio of twin components being 0.461 (7):0.539 (7). PMID:21523119

  8. Structures of cyano-biphenyl liquid crystals

    NASA Technical Reports Server (NTRS)

    Chu, Yuan-Chao; Tsang, Tung; Rahimzadeh, E.; Yin, L.

    1989-01-01

    The structures of p-alkyl- p'-cyano- bicyclohexanes, C(n)H(2n+1) (C6H10)(C6H10) CN (n-CCH), and p-alkyl- p'-cyano- biphenyls, C(n)H(2n+1) (C6H4)(C6H4) CN (n-CBP), were studied. It is convenient to use an x ray image intensification device to search for symmetric x ray diffraction patterns. Despite the similarities in molecular structures of these compounds, very different crystal structures were found. For the smectic phase of 2CCH, the structure is close to rhombohedral with threefold symmetry. In contrast, the structure is close to hexagonal close-packed with two molecules per unit cell for 4CCH. Since intermolecular forces may be quite weak for these liquid crystals systems, it appears that crystal structures change considerably when the alkyl chain length is slightly altered. Different structures were also found in the crystalline phase of n-CBP for n = 6 to 9. For n = 7 to 9, the structures are close to monclinic. The structures are reminiscent of the smectic-A liquid crystal structures with the linear molecules slightly tilted away from the c-axis. In contrast, the structure is quite different for n = 6 with the molecules nearly perpendicular to the c-axis.

  9. Studies on populations exposed to polychlorinated biphenyls.

    PubMed Central

    Kreiss, K

    1985-01-01

    Mean serum levels of polychlorinated biphenyls (PCBs) in U.S. population groups without occupational exposure to PCBs are usually between 4 and 8 ng/mL, with 95% of individuals having serum PCB measurements of less than 20. Subpopulations consuming fish taken from contaminated waters, such as Lake Michigan and near Triana, AL, have mean serum PCB levels several times those found in other general population groups and ranges that extend into concentrations found in industrial populations involved in capacitor manufacture. Two studies of general populations and several studies of industrial workers have demonstrated associations of PCBs with various serum lipids and liver enzyme levels. Six groups of investigators have found associations between PCB or chlorinated pesticide levels and blood pressure. Research efforts are needed in clarifying determinants of serum-adipose partition ratios; the utility of urinary porphyrins as a measure of subclinical hepatic effects; human metabolites and excretion of chlorinated hydrocarbons; and the relation, if any, between blood pressure and organochlorine compounds when controlled for confounding variables. Established cohorts, such as those in Triana, Lake Michigan sportsfishers, the Michigan PBB cohort, residents of farms with PCB-lined silos, and occupational groups, could all be studied further with attention to these research questions. PMID:3928345

  10. Can Stress Enhance Phytoremediation of Polychlorinated Biphenyls?

    PubMed Central

    Kalinowski, Tomasz; Halden, Rolf U.

    2012-01-01

    Abstract Phytoremediation—plant-facilitated remediation of polluted soil and groundwater—is a potentially effective treatment technology for the remediation of heavy metals and certain organic compounds. However, contaminant attenuation rates are often not rapid enough to make phytoremediation a viable option when compared with alternative treatment approaches. Different strategies are being employed to enhance the efficacy of phytoremediation, including modification to the plant genome, inoculation of the rhizosphere with specialized and/or engineered bacteria, and treatment of the soil with supplementary chemicals, such as surfactants, chelators, or fertilizers. Despite these efforts, greater breakthroughs are necessary to make phytoremediation a viable technology. Here, we introduce and discuss the concept of integrating controlled environmental stresses as a strategy for enhancing phytoremediation. Plants have a diverse suite of defense mechanisms that are only induced in response to stress. Here, we examine some stress-response mechanisms in plants, focusing on defenses involving physiological changes that alter the soil microenvironment (rhizosphere), and outline how these defense mechanisms can be co-opted to enhance the effectiveness of phytoremediation of polychlorinated biphenyls and other contaminants. PMID:23236249

  11. Waste disposal technologies for polychlorinated biphenyls.

    PubMed Central

    Piver, W T; Lindstrom, F T

    1985-01-01

    Improper practices in the disposal of polychlorinated biphenyl (PCB) wastes by land burial, chemical means and incineration distribute these chemicals and related compounds such as polychlorinated dibenzofurans (PCDFs) and polychlorinated dibenzodioxins (PCDDs) throughout the environment. The complete range of methods for disposal that have been proposed and are in use are examined and analyzed, with emphasis given to the two most commonly used methods: land burial and incineration. The understanding of aquifer contamination caused by migration of PCBs from subsurface burial sites requires a description of the physical, chemical and biological processes governing transport in unsaturated and saturated soils. For this purpose, a model is developed and solved for different soil conditions and external driving functions. The model couples together the fundamental transport phenomena for heat, mass, and moisture flow within the soil. To rehabilitate a contaminated aquifer, contaminated groundwaters are withdrawn through drainage wells, PCBs are extracted with solvents or activated carbon and treated by chemical, photochemical or thermal methods. The chemical and photochemical methods are reviewed, but primary emphasis is devoted to the use of incineration as the preferred method of disposal. After discussing the formation of PCDFs and PCDDs during combustion from chloroaromatic, chloroaliphatic, as well as organic and inorganic chloride precursors, performance characteristics of different thermal destructors are presented and analyzed. To understand how this information can be used, basic design equations are developed from governing heat and mass balances that can be applied to the construction of incinerators capable of more than 99.99% destruction with minimal to nondetectable levels of PCDFs and PCDDs. PMID:3921358

  12. Polychlorinated biphenyls as hormonally active structural analogues

    SciTech Connect

    McKinney, J.D. ); Waller, C.L. )

    1994-03-01

    Among the environmental chemicals that may be able to disrupt the endocrine systems of animals and humans, the polychlorinated biphenyls (PCBs) are a chemical class of considerable concern. One possible mechanism by which PCBs may interfere with endocrine function is their ability to mimic natural hormones. These actions reflect a close relationship between the physicochemical properties encoded in the PCB molecular structure and the responses they evoke in biological systems. These physiocochemical properties determine the molecular reactivities of PCBs and are responsible for their recognition as biological acceptors and receptors, as well as for triggering molecular mechanisms that lead to tissue response. [open quotes]Coplanarity[close quotes] of PCB phenyl rings and [open quotes]laterality[close quotes] of chlorine atoms are important structural features determining specific binding behavior with proteins and certain toxic responses in biological systems. We compare qualitative structure-activity relationships for PCBs with the limited information on the related non-coplanar chlorinated diphenyl ethers, providing further insights into the nature of the molecular recognition processes and support for the structural relationship of PCBs to thyroid hormones. Steriodlike activity requires conformational restriction and possibility hydroxylation. We offer some simple molecular recognition models to account for the importance of these different structural features in the structure-activity relationships that permit one to express PCB reactivities in terms of dioxin, thyroxine, and estradiol equivalents. The available data support the involvement of PCBs as mimics of thyroid and other steroidal hormones. The potential for reproductive and developmental toxicity associated with human exposure to PCBs is of particular concern. 53 refs., 6 figs.

  13. Process for gamma ray induced degradation of polychlorinated biphenyls

    DOEpatents

    Meikrantz, David H.; Mincher, Bruce J.; Arbon, Rodney E.

    1998-01-01

    The invention is a process for the in-situ destruction of polychlorinated biphenyl (PCB) compounds in transformer oils and transformers. These compounds are broken down selectively by irradiation of the object or mixture using spent nuclear fuel or any isotopic source of high energy gamma radiation. For example, the level of applied dose required to decompose 400 ppm of polychlorinated biphenyl in transformer oil to less than 50 ppm is 500 kilogray. Destruction of polychlorinated biphenyls to levels of less than 50 ppm renders the transformer oil or transformer non-PCB contaminated under current regulations. Therefore, this process can be used to treat PCB contaminated oil and equipment to minimize or eliminate the generation of PCB hazardous waste.

  14. Process for gamma ray induced degradation of polychlorinated biphenyls

    DOEpatents

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

    1998-08-25

    The invention is a process for the in-situ destruction of polychlorinated biphenyl (PCB) compounds in transformer oils and transformers. These compounds are broken down selectively by irradiation of the object or mixture using spent nuclear fuel or any isotopic source of high energy gamma radiation. For example, the level of applied dose required to decompose 400 ppm of polychlorinated biphenyl in transformer oil to less than 50 ppm is 500 kilograms. Destruction of polychlorinated biphenyls to levels of less than 50 ppm renders the transformer oil or transformer non-PCB contaminated under current regulations. Therefore, this process can be used to treat PCB contaminated oil and equipment to minimize or eliminate the generation of PCB hazardous waste. 5 figs.

  15. Degradation of polychlorinated biphenyls by mixed microbial cultures.

    PubMed Central

    Clark, R R; Chian, E S; Griffin, R A

    1979-01-01

    Three different enriched mixed cultures capable of degrading polychlorinated biphenylas were isolated from two soil samples and a river sediment, respectively. The predominant organisms found in all three mixed cultures were Alcaligenes odorans, Alcaligenes dentrificans, and an unidentified bacterium. The polychlorinated biphenyl isomers that were more water soluble and had lower chlorination were not only degraded at a faster rate than those that were less water soluble and had higher chlorination, but were also more completely utilized by these mixed cultures. This resulted in the presence in the environment of polychlorinated biphenyl residues consisting mainly of higher-chlorinated isomers. A form of cometabolism of polychlorinated biphenyls was also found with these cultures in the presence of acetate as the cosubstrate. PMID:110265

  16. The comparative biologic and toxic potencies of polychlorinated biphenyls and polybrominated biphenyls.

    PubMed

    Andres, J; Lambert, I; Robertson, L; Bandiera, S; Sawyer, T; Lovering, S; Safe, S

    1983-09-15

    Aroclor 1254 and fireMaster BP-6, two commercial polychlorinated biphenyl (PCB) and polybrominated biphenyl (PBB) preparations, exhibit comparable biologic and toxic effects. In the present study the commercial PBB was more active than Aroclor 1254 in causing thymic atrophy in male Wistar rats. However, a direct comparison of the relative effects of bromine vs chlorine substituents is not possible with the commercial PBB and PCB mixtures due to their complex congeneric composition. This study reports the synthesis and biologic and toxic effects of a series of laterally substituted 3,3',4,4'-tetrahalobiphenyls which contain the following variable molecular Cl/Br ratios; Br4, Br3Cl, Br2Cl2 (two isomers), BrCl3, and Cl4. 3,3',4,4'-Tetrabromobiphenyl and 3,4,4'-tribromo-3'-chlorobiphenyl (150 mumol/kg)-pretreated animals significantly inhibited the growth rate of and caused thymic atrophy in immature male Wistar rats whereas those isostereomers with reduced Br (and increased Cl) content were either less active or inactive. Pretreatment of male Wistar rats with 10 mumol/kg of the 3,3',4,4'-tetrahalobiphenyls and determination of their effects as inducers of the hepatic microsomal drug-metabolizing enzymes also illustrated the effects of the relative Cl/Br ratios on induction potencies. Both 3,3',4,4'-tetrabromo- and 3,4,4'-tribromo-3'-chlorobiphenyl maximally induced the cytochrome P-448-dependent monooxygenases, benzo[a]pyrene and 4-chlorobiphenyl hydroxylase; the order of potency of the other isostereomers was 4,4'-dibromo-3,3'-dichloro- congruent to 3,4-dibromo-3',4'-dichlorobiphenyl greater than 4-bromo-3,3',4'-trichloro- greater than 3,3',4,4'-tetrachlorobiphenyl. With few exceptions this order of potency was observed for the induction of benzo[a]pyrene hydroxylase and ethoxyresorufin O-deethylase in rat hepatoma cells in culture and for their relative binding affinities to the rat cytosolic receptor protein. The data clearly demonstrate that the biologic

  17. OXIDATION OF BIPHENYL BY A MULTICOMPONENT ENZYME SYSTEM FROM PSEUDOMONAS SP. STRAIN LB400

    EPA Science Inventory

    Pseudomonas sp. strain LB400 grows on biphenyl as the sole carbon and energy source. This organism also cooxidizes several chlorinated biphenyl congeners. Biphenyl dioxygenase activity in cell extract required addition of NAD(P)H as an electron donor for the conversion of bipheny...

  18. OXIDATION OF POLYCHLORINATED BIPHENYLS BY PSEUDOMONAS SP. STRAIN LB400 AND PSEUDOMONAS PSEUDOALCALIGENES KF707

    EPA Science Inventory

    Biphenyl-grown cells and cell extracts prepared from biphenyl-grown cells of Pseudomonas sp. strain LB400 oxidize a much wider range of chlorinated biphenyls than do analogous preparations from Pseudomonas pseudoalcaligenes KF707. These results are attributed to differences in th...

  19. 40 CFR 721.10417 - Biphenyl alkyl morpholino ketone (generic) (P-11-338).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Biphenyl alkyl morpholino ketone... Specific Chemical Substances § 721.10417 Biphenyl alkyl morpholino ketone (generic) (P-11-338). (a... generically as biphenyl alkyl morpholino ketone (PMN P-11-338) is subject to reporting under this section for...

  20. 40 CFR 721.10417 - Biphenyl alkyl morpholino ketone (generic) (P-11-338).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Biphenyl alkyl morpholino ketone... Specific Chemical Substances § 721.10417 Biphenyl alkyl morpholino ketone (generic) (P-11-338). (a... generically as biphenyl alkyl morpholino ketone (PMN P-11-338) is subject to reporting under this section for...

  1. 40 CFR 721.10417 - Biphenyl alkyl morpholino ketone (generic) (P-11-338).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Biphenyl alkyl morpholino ketone... Specific Chemical Substances § 721.10417 Biphenyl alkyl morpholino ketone (generic) (P-11-338). (a... generically as biphenyl alkyl morpholino ketone (PMN P-11-338) is subject to reporting under this section for...

  2. OXIDATION OF BIPHENYL BY A MULTICOMPONENT ENZYME SYSTEM FROM PSEUDOMONAS SP. STRAIN LB400

    EPA Science Inventory

    Pseudomonas sp. strain LB400 grows on biphenyl as the sole carbon and energy source. This organism also cooxidizes several chlorinated biphenyl congeners. Biphenyl dioxygenase activity in cell extract required addition of NAD(P)H as an electron donor for the conversion of bipheny...

  3. OXIDATION OF POLYCHLORINATED BIPHENYLS BY PSEUDOMONAS SP. STRAIN LB400 AND PSEUDOMONAS PSEUDOALCALIGENES KF707

    EPA Science Inventory

    Biphenyl-grown cells and cell extracts prepared from biphenyl-grown cells of Pseudomonas sp. strain LB400 oxidize a much wider range of chlorinated biphenyls than do analogous preparations from Pseudomonas pseudoalcaligenes KF707. These results are attributed to differences in th...

  4. Exposure Monitoring and Risk Assessment of Biphenyl in the Workplace

    PubMed Central

    Kim, Hyeon-Yeong; Shin, Sae-Mi; Ham, Miran; Lim, Cheol-Hong; Byeon, Sang-Hoon

    2015-01-01

    This study was performed to assess exposure to and the risk caused by biphenyl in the workplace. Biphenyl is widely used as a heat transfer medium and as an emulsifier and polish in industry. Vapor or high levels of dust inhalation and dermal exposure to biphenyl can cause eye inflammation, irritation of respiratory organs, and permanent lesions in the liver and nervous system. In this study, the workplace environment concentrations were assessed as central tendency exposure and reasonable maximum exposure and were shown to be 0.03 and 0.12 mg/m3, respectively. In addition, the carcinogenic risk of biphenyl as determined by risk assessment was 0.14 × 10−4 (central tendency exposure) and 0.56 × 10−4 (reasonable maximum exposure), which is below the acceptable risk value of 1.0 × 10−4. Furthermore, the central tendency exposure and reasonable maximum exposure hazard quotients were 0.01 and 0.06 for oral toxicity, 0.05 and 0.23 for inhalation toxicity, and 0.08 and 0.39 for reproduction toxicity, respectively, which are all lower than the acceptable hazard quotient of 1.0. Therefore, exposure to biphenyl was found to be safe in current workplace environments. Because occupational exposure limits are based on socioeconomic assessment, they are generally higher than true values seen in toxicity experiments. Based on the results of exposure monitoring of biphenyl, the current occupational exposure limits in Korea could be reviewed. PMID:25985312

  5. Polychlorinated biphenyl sources, environmental levels, and exposures in school buildings

    EPA Science Inventory

    Background: Building materials and components containing polychlorinated biphenyls (PCBs) were used in some U.S. school buildings until the late 1970s and may be present today. There is limited information on source factors and occupant exposures. Methods: Analysis of PCBs in mat...

  6. Polychlorinated Biphenyl Sources, Emissions, and Environmental Levels in School Buildings

    EPA Science Inventory

    Building materials and components containing polychlorinated biphenyls (PCBs) were used in some U.S. school buildings until the late 1970s and may be present today. PCB emission rates from caulk and fluorescent light ballasts were measured in laboratory chambers. PCB concentrat...

  7. Polychlorinated Biphenyls: In situ Bioremediation from the Environment

    EPA Science Inventory

    Polychlorinated biphenyls (PCBs) are a group of hydrophobic and stable organic compounds consisting of 209 possible congeners. Because of their unique physico-chemical properties, PCBs were used in a wide range of industrial applications. The properties that made PCBs useful in i...

  8. DIRECT ELECTROCHEMICAL IMMUNOSENSOR FOR POLYCHLORINATED BIPHENYLS. (R825323)

    EPA Science Inventory

    A direct electrochemical immunosensor has been developed for the determination of polychlorinated biphenyls (PCBs) in water. The assay is based on the measurement of the current due to the specific binding between PCB and anti-PCB antibody-immobilized conducting polymer matrix. T...

  9. 41 CFR 101-42.1102-2 - Polychlorinated biphenyls.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... AND DISPOSAL OF HAZARDOUS MATERIALS AND CERTAIN CATEGORIES OF PROPERTY 42.11-Special Types of Hazardous Materials and Certain Categories of Property § 101-42.1102-2 Polychlorinated biphenyls. (a... 41 Public Contracts and Property Management 2 2013-07-01 2012-07-01 true Polychlorinated...

  10. Polychlorinated Biphenyl Sources, Emissions, and Environmental Levels in School Buildings

    EPA Science Inventory

    Building materials and components containing polychlorinated biphenyls (PCBs) were used in some U.S. school buildings until the late 1970s and may be present today. PCB emission rates from caulk and fluorescent light ballasts were measured in laboratory chambers. PCB concentrat...

  11. Polychlorinated Biphenyls: In situ Bioremediation from the Environment

    EPA Science Inventory

    Polychlorinated biphenyls (PCBs) are a group of hydrophobic and stable organic compounds consisting of 209 possible congeners. Because of their unique physico-chemical properties, PCBs were used in a wide range of industrial applications. The properties that made PCBs useful in i...

  12. Polychlorinated biphenyl sources, environmental levels, and exposures in school buildings

    EPA Science Inventory

    Background: Building materials and components containing polychlorinated biphenyls (PCBs) were used in some U.S. school buildings until the late 1970s and may be present today. There is limited information on source factors and occupant exposures. Methods: Analysis of PCBs in mat...

  13. DIRECT ELECTROCHEMICAL IMMUNOSENSOR FOR POLYCHLORINATED BIPHENYLS. (R825323)

    EPA Science Inventory

    A direct electrochemical immunosensor has been developed for the determination of polychlorinated biphenyls (PCBs) in water. The assay is based on the measurement of the current due to the specific binding between PCB and anti-PCB antibody-immobilized conducting polymer matrix. T...

  14. A cohort study on mortality and exposure to polychlorinated biphenyls.

    PubMed

    Hsieh, S F; Yen, Y Y; Lan, S J; Hsieh, C C; Lee, C H; Ko, Y C

    1996-01-01

    In 1979, an outbreak of food poisoning ("Yu-Cheng") occurred in Central Taiwan, ROC, involving more than 2000 people. The event was caused by ingestion of rice oil contaminated with polychlorinated derivatives of biphenyls, dibenzofurans, and quaterphenyls. A retrospective cohort study on mortality was undertaken, and possible long-term health effects in the affected individuals were studied. The mortality experience of 1940 victims (929 males, 1011 females) between 1980 and 1991 was compared with the expected numbers, which were calculated from national and local mortality rates. By the end of 1991, 102 deaths were identified, thus producing a standardized mortality ratio (SMR) of overall mortality of 0.99 for males and 1.34 for females. Total cancer mortality was lower than in each comparison group. Mortality from liver diseases was elevated significantly (SMR = 3.22), especially during the first 3 y after the food-poisoning event (SMR = 10.76). Increased clinical severity of polychlorinated biphenyl intoxication was associated with increased mortality from all causes and from liver diseases. In summary, there was a positive association between mortality and intoxication dose, and severe polychlorinated biphenyl poisoning acutely affected mainly the liver. A continued follow-up of this cohort would be valuable in the study of long-term health effects of polychlorinated biphenyl poisoning.

  15. IRIS Toxicological Review of Biphenyl (Interagency Science Consultation Draft)

    EPA Science Inventory

    On September 30, 2011, the draft Toxicological Review of Biphenyl and the charge to external peer reviewers were released for external peer review and public comment. The Toxicological Review and charge were reviewed internally by EPA and by other federal agencies and White House...

  16. IRIS Toxicological Review of Biphenyl (Interagency Science Discussion Draft)

    EPA Science Inventory

    EPA is releasing the draft report, Toxicological Review of Biphenyl, that was distributed to other federal agencies and the Executive Office of the President for comment during Interagency Science Discussion (IASD) (Step 6b) of the IRIS assessment development process. Interagenc...

  17. 77 FR 54818 - Polychlorinated Biphenyls (PCBs): Revisions to Manifesting Regulations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-06

    ...The Environmental Protection Agency (``EPA'' or ``the Agency'') is issuing this direct final rule to update and clarify several sections of the Polychlorinated Biphenyl (PCB) regulations associated with the manifesting requirements, which uses the Resource Conservation and Recovery Act (RCRA) Uniform Hazardous Waste Manifest, under the Toxic Substances Control Act (TSCA). Today's changes are......

  18. 21 CFR 109.30 - Tolerances for polychlorinated biphenyls (PCB's).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Tolerances for polychlorinated biphenyls (PCB's). 109.30 Section 109.30 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION UNAVOIDABLE CONTAMINANTS IN FOOD FOR HUMAN CONSUMPTION AND...

  19. 21 CFR 109.30 - Tolerances for polychlorinated biphenyls (PCB's).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Tolerances for polychlorinated biphenyls (PCB's). 109.30 Section 109.30 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION UNAVOIDABLE CONTAMINANTS IN FOOD FOR HUMAN CONSUMPTION AND...

  20. 21 CFR 109.30 - Tolerances for polychlorinated biphenyls (PCB's).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Tolerances for polychlorinated biphenyls (PCB's). 109.30 Section 109.30 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION UNAVOIDABLE CONTAMINANTS IN FOOD FOR HUMAN CONSUMPTION AND...

  1. 21 CFR 109.30 - Tolerances for polychlorinated biphenyls (PCB's).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Tolerances for polychlorinated biphenyls (PCB's). 109.30 Section 109.30 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION UNAVOIDABLE CONTAMINANTS IN FOOD FOR HUMAN CONSUMPTION AND...

  2. IRIS Toxicological Review of Biphenyl (Interagency Science Discussion Draft)

    EPA Science Inventory

    EPA is releasing the draft report, Toxicological Review of Biphenyl, that was distributed to other federal agencies and the Executive Office of the President for comment during Interagency Science Discussion (IASD) (Step 6b) of the IRIS assessment development process. Interagenc...

  3. IRIS Toxicological Review of Biphenyl (Interagency Science Consultation Draft)

    EPA Science Inventory

    On September 30, 2011, the draft Toxicological Review of Biphenyl and the charge to external peer reviewers were released for external peer review and public comment. The Toxicological Review and charge were reviewed internally by EPA and by other federal agencies and White House...

  4. 41 CFR 101-42.1102-2 - Polychlorinated biphenyls.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... environmental contaminant requiring special handling and disposal in accordance with the U.S. Environmental... airports, the Department of Defense or the Federal Aviation Administration, respectively, shall obtain the... polychlorinated biphenyls (PCBs), a toxic environmental contaminant, require(s) special handling and disposal...

  5. 41 CFR 101-42.1102-2 - Polychlorinated biphenyls.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... environmental contaminant requiring special handling and disposal in accordance with the U.S. Environmental... airports, the Department of Defense or the Federal Aviation Administration, respectively, shall obtain the... polychlorinated biphenyls (PCBs), a toxic environmental contaminant, require(s) special handling and disposal...

  6. Polychlorinated biphenyls (PCBs) in San Francisco Bay.

    PubMed

    Davis, J A; Hetzel, F; Oram, J J; McKee, L J

    2007-09-01

    San Francisco Bay is facing a legacy of polychlorinated biphenyls (PCBs) spread widely across the land surface of the watershed, mixed deep into the sediment of the Bay, and contaminating the Bay food web to a degree that poses health risks to humans and wildlife. In response to this persistent problem, water quality managers are establishing a PCB total maximum daily load (TMDL) and implementation plan to accelerate the recovery of the Bay from decades of PCB contamination. This article provides a review of progress made over the past 15 years in managing PCBs and understanding their sources, pathways, fate, and effects in the Bay, and highlights remaining information needs that should be addressed in the next 10 years. The phaseout of PCBs during the 1970s and the 1979 federal ban on sale and production led to gradual declines from the 1970s to the present. However, 25 years after the ban, PCB concentrations in some Bay sport fish today are still more than ten times higher than the threshold of concern for human health. Without further management action it appears that the general recovery of the Bay from PCB contamination will take many more decades. PCB concentrations in sport fish were, along with mercury, a primary cause of a consumption advisory for the Bay and the consequent classification of the Bay as an impaired water body. Several sources of information indicate that PCB concentrations in the Bay may also be high enough to adversely affect wildlife, including rare and endangered species. The greater than 90% reduction in food web contamination needed to meet the targets for protection of human health would likely also generally eliminate risks to wildlife. PCB contamination in the Bay is primarily associated with industrial areas along the shoreline and in local watersheds. Strong spatial gradients in PCB concentrations persist decades after the release of these chemicals to Bay Area waterways. Through the TMDL process, attention is being more sharply

  7. Two-photon spectroscopy of the biphenyl chromophore. The electronic excited states of biphenyl and fluorene below 50000 cm -1

    NASA Astrophysics Data System (ADS)

    Dick, Bernhard; Hohlneicher, Georg

    1985-03-01

    The two-proton excitation spectra of biphenyl and fluorene in dilute solution have been measured up to 50000 cm -1. Both spectra exhibit a medium intense band system in the range 32000-42000 cm -1, and a strong band above 45000 cm -1. The lowest frequency feature is assigned to a B 3 symmetry transition in biphenyl and the corresponding B 2 transition in fluorene. The polarization of the higher bands leads to the assignment of two A states at 38000 and 47000 cm -1. The origin of the electronically excited states of the biphenyl chromophore is discussed by simple composite molecule considerations as well as CNDO Cl calculations. The latter give a semiquantitative picture of transition energies and transition probabilities for one-and two-photon allowed excitations. A compilation of one-photon spectra and calculations from the literature is included in the analysis to provide a consistent picture of the electronically excited states of the biphenyl chromophore up to 50000 cm -1.

  8. Classification of polychlorinated biphenyl residues: isomers vs. homologue concentrations in modeling aroclors and polychlorinated biphenyl residues

    SciTech Connect

    Stalling, D.L.; Schwartz, T.R.; Dunn, W.J. III; Wold, S.

    1987-07-15

    SIMCA (soft independent modeling by class analogy), a principal components chemometric modeling program, was used to examine complex mixtures of polychlorinated biphenyl residues (PCBs) in fish and turtles. Individual PCB isomers were measured by electron capture capillary gas chromatography. The authors calculated PCB (Cl/sub 1-10/) congener concentrations by summing 105 isomer concentrations into homologue subgroups. Information theory was used to estimate the maximum information content of the two data sets. The authors compared the results from principal components modeling of samples and Aroclors by using both isomer and Cl/sub 1-10/ homologue concentrations. Modeling of normalized data from Aroclors or their mixtures gave similar sample score plots for both data sets. However, modeling environmental sample congener concentrations gave erroneous classification results when compared to results from modeling isomer data. Although the Cl/sub 1-10/ sums accurately reflect the concentration of PCBs in the sample, calculations to determine PCB profiles as Aroclor mixtures should be made by using individual PCB isomers.

  9. Identification of novel extracellular protein for PCB/biphenyl metabolism in Rhodococcus jostii RHA1.

    PubMed

    Atago, Yuki; Shimodaira, Jun; Araki, Naoto; Bin Othman, Nor'azizi; Zakaria, Zuriati; Fukuda, Masao; Futami, Junichiro; Hara, Hirofumi

    2016-05-01

    Rhodococcus jostii RHA1 (RHA1) degrades polychlorinated biphenyl (PCB) via co-metabolism with biphenyl. To identify the novel open reading frames (ORFs) that contribute to PCB/biphenyl metabolism in RHA1, we compared chromatin immunoprecipitation chip and transcriptomic data. Six novel ORFs involved in PCB/biphenyl metabolism were identified. Gene deletion mutants of these 6 ORFs were made and were tested for their ability to grow on biphenyl. Interestingly, only the ro10225 deletion mutant showed deficient growth on biphenyl. Analysis of Ro10225 protein function showed that growth of the ro10225 deletion mutant on biphenyl was recovered when exogenous recombinant Ro10225 protein was added to the culture medium. Although Ro10225 protein has no putative secretion signal sequence, partially degraded Ro10225 protein was detected in conditioned medium from wild-type RHA1 grown on biphenyl. This Ro10225 fragment appeared to form a complex with another PCB/biphenyl oxidation enzyme. These results indicated that Ro10225 protein is essential for the formation of the PCB/biphenyl dioxygenase complex in RHA1.

  10. DNA-stable isotope probing integrated with metagenomics for retrieval of biphenyl dioxygenase genes from polychlorinated biphenyl-contaminated river sediment.

    PubMed

    Sul, Woo Jun; Park, Joonhong; Quensen, John F; Rodrigues, Jorge L M; Seliger, Laurie; Tsoi, Tamara V; Zylstra, Gerben J; Tiedje, James M

    2009-09-01

    Stable isotope probing with [(13)C]biphenyl was used to explore the genetic properties of indigenous bacteria able to grow on biphenyl in PCB-contaminated River Raisin sediment. A bacterial 16S rRNA gene clone library generated from [(13)C]DNA after a 14-day incubation with [(13)C]biphenyl revealed the dominant organisms to be members of the genera Achromobacter and Pseudomonas. A library built from PCR amplification of genes for aromatic-ring-hydroxylating dioxygenases from the [(13)C]DNA fraction revealed two sequence groups similar to bphA (encoding biphenyl dioxygenase) of Comamonas testosteroni strain B-356 and of Rhodococcus sp. RHA1. A library of 1,568 cosmid clones was produced from the [(13)C]DNA fraction. A 31.8-kb cosmid clone, detected by aromatic dioxygenase primers, contained genes of biphenyl dioxygenase subunits bphAE, while the rest of the clone's sequence was similar to that of an unknown member of the Gammaproteobacteria. A discrepancy in G+C content near the bphAE genes implies their recent acquisition, possibly by horizontal transfer. The biphenyl dioxygenase from the cosmid clone oxidized biphenyl and unsubstituted and para-only-substituted rings of polychlorinated biphenyl (PCB) congeners. A DNA-stable isotope probing-based cosmid library enabled the retrieval of functional genes from an uncultivated organism capable of PCB metabolism and suggest dispersed dioxygenase gene organization in nature.

  11. IRIS Toxicological Review of Biphenyl (External Review Draft) ...

    EPA Pesticide Factsheets

    EPA is conducting a peer review of the scientific basis supporting the human health hazard and dose-response assessment of biphenyl that will appear in the Integrated Risk Information System (IRIS) database. EPA is undertaking a new health assessment for biphenyl for the Integrated Risk Information System (IRIS). The outcome of this project will be a Toxicological Review and IRIS and IRIS Summary of biohenyl that will be entered on the IRIS database. IRIS is an EPA database containing Agency scientific positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information to evaluate potential public health risks associated with exposure assessment information to evaluate potential public health risks associated with environmental contaminants. The IRIS database is relied on for the development of risk assessments sites-specific environmental decisions, and rule making.

  12. Hydroxylated biphenyls as tyrosinase inhibitor: A spectrophotometric and electrochemical study.

    PubMed

    Ruzza, Paolo; Serra, Pier Andrea; Fabbri, Davide; Dettori, Maria Antonietta; Rocchitta, Gaia; Delogu, Giovanna

    2017-01-27

    A small collection of C2-symmetry hydroxylated biphenyls was prepared by straightforward methods and the capability to act as inhibitors of tyrosinase has been evaluated by both spectrophotometric and electrochemical assays. Our attention was focused on the diphenolase activity of this enzyme characterized by the absence of the characteristic lag time of enzymatic reaction of its monophenolase activity. To this purpose, we evaluated the capability of tyrosinase to oxidize a natural o-diphenol substrate to o-quinone analyzing the changes in the UV-Vis spectrum of a solution of caffeic acid and the reduction of the cathodic current in a tyrosinase-biosensor, respectively. Results of both the methods were comparable. Most of the compounds possessed higher inhibitory activity compared to compound 1, a known hydroxylated biphenyl inhibitor of tyrosinase.

  13. Polychlorinated Biphenyl Presence in the Columbia River Corridor

    SciTech Connect

    R. M. Hermann

    2007-09-06

    The U. S. Department of Energy (DOE) is required by Comprehensive Environmental Response, Compensation, and Liability Act of 1980 regulations to develop a conceptual understanding of potential contaminant releases from the Hanford Site based on an evaluation of existing data and known historical practices. Polychlorinated biphenyls (PCBs) are one environmental contaminant potentially released through leaks, spills, or disposal. This document presents a summary of selected relevant existing information, including environmental studies and Hanford Site analytical data.

  14. CORRECTIVE ACTION PLAN FOR CORRECTIVE ACTION UNIT 528: POLYCHLORINATED BIPHENYLS CONTAMINATION NEVADA TEST SITE, NEVADA

    SciTech Connect

    BECHTEL NEVADA

    2005-06-01

    Corrective Action Unit (CAU) 528: Polychlorinated Biphenyls Contamination is listed in Appendix III of the Federal Facility Agreement and Consent Order (FFACO, 1996) and is located in Area 25 of the Nevada Test Site. CAU 528 was created to address polychlorinated biphenyl (PCB) contamination identified during the CAU 262 corrective action investigation. CAU 528 consists of one Corrective Action Site (CAS): CAS 25-27-03, Polychlorinated Biphenyls Surface Contamination.

  15. Complete Reductive Dehalogenation of Brominated Biphenyls by Anaerobic Microorganisms in Sediment

    PubMed Central

    Bedard, Donna L.; Van Dort, Heidi M.

    1998-01-01

    We sought to determine whether microorganisms from the polychlorinated biphenyl (PCB)-contaminated sediment in Woods Pond (Lenox, Mass.) could dehalogenate brominated biphenyls. The PCB dechlorination specificities for the microorganisms in this sediment have been well characterized. This allowed us to compare the dehalogenation specificities for brominated biphenyls and chlorinated biphenyls within a single sediment. Anaerobic sediment microcosms were incubated separately at 25°C with 16 different mono- to tetrabrominated biphenyls (350 μM) and disodium malate (10 mM). Samples were extracted and analyzed by gas chromatography with an electron capture detector and a mass spectrometer detector at various times for up to 54 weeks. All of the tested brominated biphenyls were dehalogenated. For most congeners, including 2,6-dibromobiphenyl (26-BB) and 24-25-BB, the dehalogenation began within 1 to 2 weeks. However, for 246-BB and 2-2-BB, debromination was first observed at 7 and 14 weeks, respectively. Most intermediate products did not persist, but when 2-2-BB was produced as a dehalogenation product, it persisted for at least 15 weeks before it was dehalogenated to 2-BB and then to biphenyl. The dehalogenation specificities for brominated and chlorinated biphenyls were similar: meta and para substituents were generally removed first, and ortho substituents were more recalcitrant. However, the brominated biphenyls were better dehalogenation substrates than the chlorinated biphenyls. All of the tested bromobiphenyls, including those with ortho and unflanked meta and para substituents, were ultimately dehalogenated to biphenyl, whereas their chlorinated counterparts either were not dehalogenation substrates or were only partially dehalogenated. Our data suggest that PCB-dechlorinating microorganisms may be able to dehalogenate brominated biphenyls and may exhibit a relaxed specificity for these substrates. PMID:16349530

  16. Polychlorinated Biphenyls, Organochlorines & PD Risk: A Case Control Study in Alaskan Natives

    DTIC Science & Technology

    2011-05-01

    1-0490 TITLE: Polychlorinated Biphenyls, Organochlorines & PD Risk: A Case Control Study in Alaskan Natives PRINCIPAL INVESTIGATOR...Polychlorinated Biphenyls, Organochlorines & PD Risk: A Case 5a. CONTRACT NUMBER W81XWH-04-1-0490 Control Study in Alaskan Natives 5b. GRANT NUMBER...to pol ychlorinated biphenyl (PCBs) residues, organochlorine pesticides and methylmercury with PD. The hy pothesis is that increased exposure to t

  17. Polychlorinated Biphenyls, Organochlorines & PD Risk: A Case Control Study in Alaska

    DTIC Science & Technology

    2010-05-01

    TITLE: Polychlorinated Biphenyls, Organochlorines & PD Risk: A Case Control Study in Alaska PRINCIPAL INVESTIGATOR: Caroline M. Tanner, M.D...2010 4. TITLE AND SUBTITLE Polychlorinated Biphenyls, Organochlorines & PD Risk: A Case 5a. CONTRACT NUMBER W81XWH-04-1-0490 Control Study in...now in progress in Anchorage. 15. SUBJECT TERMS Parkinson’s disease, Polychlorinated biphenyl, Organochlorine pesticides, Methylmercury, Alaska

  18. Assessment of bioaccumulation of biphenyls in the trophic chain of a coastal area of Parana, Brazil.

    PubMed

    Froehner, Sandro; Maceno, Marcell

    2010-05-01

    The presence of biphenyl was investigated in sediments and water in Paranagua Bay. Chemicals compounds like biphenyl can cause several effects on the ecosystems such as bioaccumulation. Biphenyl and similar compounds are subject to bioaccumulation, which in turn may harm the local ecosystem. The bioaccumulation in the local trophic chain was evaluated using a mathematical model based on toxicokinetic properties of the compound in the organisms. The results showed that even in water, the concentration of biphenyl was high, 0.82 ng/L. Also, in the fishes, the concentrations calculated by the model were higher than the maximum than the maximum allowed for human consumption.

  19. Synergistic Processing of Biphenyl and Benzoate: Carbon Flow Through the Bacterial Community in Polychlorinated-Biphenyl-Contaminated Soil

    NASA Astrophysics Data System (ADS)

    Leewis, Mary-Cathrine; Uhlik, Ondrej; Leigh, Mary Beth

    2016-02-01

    Aerobic mineralization of PCBs, which are toxic and persistent organic pollutants, involves the upper (biphenyl, BP) and lower (benzoate, BZ) degradation pathways. The activity of different members of the soil microbial community in performing one or both pathways, and their synergistic interactions during PCB biodegradation, are not well understood. This study investigates BP and BZ biodegradation and subsequent carbon flow through the microbial community in PCB-contaminated soil. DNA stable isotope probing (SIP) was used to identify the bacterial guilds involved in utilizing 13C-biphenyl (unchlorinated analogue of PCBs) and/or 13C-benzoate (product/intermediate of BP degradation and analogue of chlorobenzoates). By performing SIP with two substrates in parallel, we reveal microbes performing the upper (BP) and/or lower (BZ) degradation pathways, and heterotrophic bacteria involved indirectly in processing carbon derived from these substrates (i.e. through crossfeeding). Substrate mineralization rates and shifts in relative abundance of labeled taxa suggest that BP and BZ biotransformations were performed by microorganisms with different growth strategies: BZ-associated bacteria were fast growing, potentially copiotrophic organisms, while microbes that transform BP were oligotrophic, slower growing, organisms. Our findings provide novel insight into the functional interactions of soil bacteria active in processing biphenyl and related aromatic compounds in soil, revealing how carbon flows through a bacterial community.

  20. Synergistic Processing of Biphenyl and Benzoate: Carbon Flow Through the Bacterial Community in Polychlorinated-Biphenyl-Contaminated Soil.

    PubMed

    Leewis, Mary-Cathrine; Uhlik, Ondrej; Leigh, Mary Beth

    2016-02-26

    Aerobic mineralization of PCBs, which are toxic and persistent organic pollutants, involves the upper (biphenyl, BP) and lower (benzoate, BZ) degradation pathways. The activity of different members of the soil microbial community in performing one or both pathways, and their synergistic interactions during PCB biodegradation, are not well understood. This study investigates BP and BZ biodegradation and subsequent carbon flow through the microbial community in PCB-contaminated soil. DNA stable isotope probing (SIP) was used to identify the bacterial guilds involved in utilizing (13)C-biphenyl (unchlorinated analogue of PCBs) and/or (13)C-benzoate (product/intermediate of BP degradation and analogue of chlorobenzoates). By performing SIP with two substrates in parallel, we reveal microbes performing the upper (BP) and/or lower (BZ) degradation pathways, and heterotrophic bacteria involved indirectly in processing carbon derived from these substrates (i.e. through crossfeeding). Substrate mineralization rates and shifts in relative abundance of labeled taxa suggest that BP and BZ biotransformations were performed by microorganisms with different growth strategies: BZ-associated bacteria were fast growing, potentially copiotrophic organisms, while microbes that transform BP were oligotrophic, slower growing, organisms. Our findings provide novel insight into the functional interactions of soil bacteria active in processing biphenyl and related aromatic compounds in soil, revealing how carbon flows through a bacterial community.

  1. Synergistic Processing of Biphenyl and Benzoate: Carbon Flow Through the Bacterial Community in Polychlorinated-Biphenyl-Contaminated Soil

    PubMed Central

    Leewis, Mary-Cathrine; Uhlik, Ondrej; Leigh, Mary Beth

    2016-01-01

    Aerobic mineralization of PCBs, which are toxic and persistent organic pollutants, involves the upper (biphenyl, BP) and lower (benzoate, BZ) degradation pathways. The activity of different members of the soil microbial community in performing one or both pathways, and their synergistic interactions during PCB biodegradation, are not well understood. This study investigates BP and BZ biodegradation and subsequent carbon flow through the microbial community in PCB-contaminated soil. DNA stable isotope probing (SIP) was used to identify the bacterial guilds involved in utilizing 13C-biphenyl (unchlorinated analogue of PCBs) and/or 13C-benzoate (product/intermediate of BP degradation and analogue of chlorobenzoates). By performing SIP with two substrates in parallel, we reveal microbes performing the upper (BP) and/or lower (BZ) degradation pathways, and heterotrophic bacteria involved indirectly in processing carbon derived from these substrates (i.e. through crossfeeding). Substrate mineralization rates and shifts in relative abundance of labeled taxa suggest that BP and BZ biotransformations were performed by microorganisms with different growth strategies: BZ-associated bacteria were fast growing, potentially copiotrophic organisms, while microbes that transform BP were oligotrophic, slower growing, organisms. Our findings provide novel insight into the functional interactions of soil bacteria active in processing biphenyl and related aromatic compounds in soil, revealing how carbon flows through a bacterial community. PMID:26915282

  2. [Diversity of the Key Biphenyl Destruction Genes in the Microbial Community of the Anadyr Bay Coastal Sediments].

    PubMed

    Shumkova, E S; Voronina, A O; Kuznetsova, N V; Plotnikova, E G

    2015-07-01

    Biphenyl 2,3-dioxygenase is the key enzyme involved in the bacterial destruction of biphenyl and polychlo- rinated biphenyls (PCBs), which are highly stable toxic compounds. The diversity of bphA1 genes encoding the biphenyl 2,3-dioxygenase a subunit of biphenyl-decomposing bacteria from the microbial community of the Bering Sea coastal sediments (the Anadyr port area) was studied. The enrichment culture was obtained by the incubation of bottom sediments samples with biphenyl as the only carbon source. It was followed by total DNA extraction and PCR analysis with degenerate primers specific to the bacterial biphenyl 2,3-dioxygenase a subunit genes. Subsequent cloning of the PCR products led to the identification of three types of aromatic dioxygenase genes, which appeared to be phylogenetically close to the genes of the biphenyl/toluene dioxygenase and 3-phenylpropionate dioxygenase subfamilies of the Actinomycetales bacteria.

  3. Ideal gas thermodynamic properties for the phenyl, phenoxy, and o-biphenyl radicals

    NASA Technical Reports Server (NTRS)

    Burcat, A.; Zeleznik, F. J.; Mcbride, B. J.

    1985-01-01

    Ideal gas thermodynamic properties of the phenyl and o-biphenyl radicals, their deuterated analogs and the phenoxy radical were calculated to 5000 K using estimated vibrational frequencies and structures. The ideal gas thermodynamic properties of benzene, biphenyl, their deuterated analogs and phenyl were also calculated.

  4. Complete Genome Sequence of the Polychlorinated Biphenyl Degrader Rhodococcus sp. WB1

    PubMed Central

    Yu, Man; Shen, Alin

    2016-01-01

    Rhodococcus sp. WB1 is a polychlorinated biphenyl degrader which was isolated from contaminated soil in Zhejiang, China. Here, we present the complete genome sequence. The analysis of this genome indicated that a biphenyl-degrading gene cluster and several xenobiotic metabolism pathways are harbored. PMID:27738025

  5. Polychlorinated biphenyls may alter marine trophic pathways by reducing phytoplankton size and production.

    PubMed

    O'Connors, H B; Wurster, C F; Powers, C D; Biggs, D C; Rowland, R G

    1978-08-25

    Polychlorinated biphenyls at concentrations of 1 to 10 micrograms per liter reduced phytoplankton biomass and size in natural estuarine phytoplankton communities grown within dialysis bags in situ in an estuarine marsh. In polychlorinated biphenyls-contaminated waters, these changes could increase the number of trophic levels and divert the flow of biomass from harvestable fish to jellyfish and other gelatinous predators.

  6. Health and productivity of dairy cows fed polychlorinated biphenyls

    SciTech Connect

    Willett, L.B.; Liu, T.T.; Durst, H.I.; Smith, K.L.; Redman, D.R.

    1987-07-01

    Holstein cows were studied through a complete lactation, a nonlactating period, and 42 days of a subsequent lactation for overt and subtle responses to a commercial mixture of polychlorinated biphenyls. Dosed cows (n = 4) received consecutive 60-day periods of daily dosing with 10, 100, and 1000 mg of Aroclor 1254. Control cows (n = 6) received daily sham doses. The following were recorded: daily milk production, feed intake, and health observations; weekly body weight, temperature, heart and respiratory rates and rectal palpation; semi-monthly clinical chemistry determinations; and monthly milk fat, microbiological culture of quarter foremilk samples, and composite milk somatic cell counts. Mean daily milk production (22.4 +/- 1.1 vs 24.8 +/- 1.0 kg) and net energy of a complete lactation (1.46 +/- 0.05 vs 1.45 +/- 0.03 Mcal/kg dry matter intake) were not different (p = 0.85) for control and PCB-dosed cows. Milk production during the first 42 days of the subsequent lactation was also similar for control and dosed cows. Occurrences of injuries, dysfunctions, and general infections were not related to polychlorinated biphenyl exposure. Intramammary infections were detected for both lactations with 51 and 32 infections detected in microbiological cultures, respectively, for the control and dosed groups. Environmental pathogens were most frequently isolated from cases of clinically apparent mastitis. The majority of quarter infections detected were due to Corynebacterium bovis. Only one animal (dosed, necropsy revealed left oviduct obstructed) failed to conceive with three to six services required before conception for the other control and dosed cows. Exposure to polychlorinated biphenyls resulting in maximal residues in milk fat, near 100 micrograms/g, had no apparent effect on health and productivity.

  7. Fluorescent Biphenyl Derivatives of Phenylalanine Suitable for Protein Modification

    PubMed Central

    Chen, Shengxi; Fahmi, Nour Eddine; Bhattacharya, Chandrabali; Wang, Lin; Jin, Yuguang; Benkovic, Stephen J.; Hecht, Sidney M.

    2013-01-01

    In a recent study, we demonstrated that structurally compact fluorophores incorporated into the side chains of amino acids could be introduced into dihydrofolate reductase from E. coli (ecDHFR) with minimal disruption of protein structure or function, even where the site of incorporation was within a folded region of the protein. The modified proteins could be employed for FRET measurements, providing sensitive monitors of changes in protein conformation. The very favorable results achieved in that study encouraged us to prepare additional fluorescent amino acids of potential utility for studying protein dynamics. Presently, we describe the synthesis and photophysical characterization of four positional isomers of biphenyl-phenylalanine, all of which were found to exhibit potentially useful fluorescent properties. All four phenylalanine derivatives were used to activate suppressor tRNA transcripts, and incorporated into multiple positions of ecDHFR. All phenylalanine derivatives were incorporated with good efficiency into position 16 of ecDHFR, and afforded modified proteins which consumed NADPH at rates up to about twice the rate measured for wild type. This phenomenon has been noted on a number of occasions previously and shown to be due to an increase in the off-rate of tetrahydrofolate from the enzyme, altering a step that is normally rate limiting. When introduced into sterically accessible position 49, the four phenylalanine derivatives afforded DHFRs having catalytic function comparable to wild type. The four phenylalanine derivatives were also introduced into position 115 of ecDHFR, which is known to be a folded region of the protein less tolerant of structural alteration. As anticipated, significant differences were noted in the catalytic efficiencies of the derived proteins. The ability of two of the sizeable biphenyl-phenylalanine derivatives to be accommodated at position 115 with minimal perturbation of DHFR function is attributed to rotational

  8. Fluorescent biphenyl derivatives of phenylalanine suitable for protein modification.

    PubMed

    Chen, Shengxi; Fahmi, Nour Eddine; Bhattacharya, Chandrabali; Wang, Lin; Jin, Yuguang; Benkovic, Stephen J; Hecht, Sidney M

    2013-11-26

    In a recent study, we demonstrated that structurally compact fluorophores incorporated into the side chains of amino acids could be introduced into dihydrofolate reductase from Escherichia coli (ecDHFR) with minimal disruption of protein structure or function, even when the site of incorporation was within a folded region of the protein. The modified proteins could be employed for FRET measurements, providing sensitive monitors of changes in protein conformation. The very favorable results achieved in that study encouraged us to prepare additional fluorescent amino acids of potential utility for studying protein dynamics. Presently, we describe the synthesis and photophysical characterization of four positional isomers of biphenyl-phenylalanine, all of which were found to exhibit potentially useful fluorescent properties. All four phenylalanine derivatives were used to activate suppressor tRNA transcripts and incorporated into multiple positions of ecDHFR. All phenylalanine derivatives were incorporated with good efficiency into position 16 of ecDHFR and afforded modified proteins that consumed NADPH at rates up to about twice the rate measured for wild type. This phenomenon has been noted on a number of occasions previously and shown to be due to an increase in the off-rate of tetrahydrofolate from the enzyme, altering a step that is normally rate limiting. When introduced into sterically accessible position 49, the four phenylalanine derivatives afforded DHFRs having catalytic function comparable to wild type. The four phenylalanine derivatives were also introduced into position 115 of ecDHFR, which is known to be a folded region of the protein less tolerant of structural alteration. As anticipated, significant differences were noted in the catalytic efficiencies of the derived proteins. The ability of two of the sizable biphenyl-phenylalanine derivatives to be accommodated at position 115 with minimal perturbation of DHFR function is attributed to rotational

  9. Pesticide Monitoring Study. Evaluation of Silicic Acid Column Pesticide/Polychlorinated Biphenyl Separation Procedure: Recovery and Elution Patterns of 24 Pesticides and Pesticide Metabolites and Two Polychlorinated Biphenyls.

    DTIC Science & Technology

    1979-02-01

    This report presents silicic acid column recovery and elution characteristics for 24 pesticides and pesticide metabolites and two polychlorinated ... biphenyls . The average percent recoveries for all except a few compounds studied were essentially quantitative. The average percent relative standard

  10. Polychlorinated biphenyls (PCBs) depress allogeneic natural cytotoxicity by earthworm coelomocytes

    SciTech Connect

    Suzuki, M.M.; Cooper, E.L.; Eyambe, G.S.; Goven, A.J.; Fitzpatrick, L.C.; Venables, B.J. |

    1995-10-01

    Coelomocytes of the earthworm Lumbricus terrestris caused significant spontaneous allogeneic cytotoxicity in a 24-h trypan blue assay, but not in an assay using lactate dehydrogenase (LDH) release. Allogeneic cytotoxicity assays using cells from worms exposed to polychlorinated biphenyls (PCBs) suggest that PCBs can suppress a natural killing (NK-like) reaction. The implications of this work are twofold: understanding the evolution of natural killing (NK-like) activity and providing preliminary information on how spontaneous killing, a component of cellular immunity, may be compromised by pollutants.

  11. Polychlorinated biphenyl (PCB) partitioning between adipose tissue and serum

    SciTech Connect

    Brown, J.F. Jr.; Lawton, R.W.

    1984-09-01

    It has been recently suggested that variabilities in the partitioning of chronically retained lipophilic xenobiotics between adipose tissue and serum may be relatable to variations in the lipid content of the serum. Here, the authors present theoretical considerations and experimental data showing that this is indeed the case for polychlorinated biphenyls (PCBs) in humans. At equilibrium, in the absence of active transport, any lipophilic substance must distribute itself among body tissues in such a way that its chemical activity and also its chemical potential are the same at all points. In order to verify the theoretical relationships, three sorts of data relating to serum PCB levels in a human population were examined.

  12. Degradation of polychlorinated biphenyls (PCBs) using palladized iron

    SciTech Connect

    West, O.R.; Liang, L.; Holden, W.L.

    1996-06-01

    Contamination from polychlorinated biphenyls (PCBs) is a persistent problem within the Department of Energy complex, as well as in numerous industrial sites around the US. To date, commercially available technologies for destroying these highly stable compounds involve degradation at elevated temperatures either through incineration or base-catalyzed dehalogenation at 300{degrees}C. Since the heating required with these processes substantially increases the costs for treatment of PCB-contaminated wastes, there is a need for finding an alternative approach where PCB can be degraded at ambient temperatures. This report describes the degradation of PCB`s utilizing the bimetallic substrate of iron/palladium.

  13. Determination of polychlorinated biphenyls in Antarctic macroalgae Desmarestia sp.

    PubMed

    Montone, R C; Taniguchi, S; Sericano, J; Weber, R R; Lara, W H

    2001-09-28

    Selected polychlorinated biphenyl (PCB) congeners were measured in Desmarestia sp., an abundant algae in the Antarctica Peninsula and South Shetlands. Samples were collected from various points of Admiralty Bay, King George Island, Antarctic Peninsula, during the 1993-1994 austral summer. Total PCB concentrations ranged from 0.46 to 3.86 ng g(-1) (dry weight). Predominant PCB congeners were 52, 101, 110, 138 and 153. The low levels of PCBs found on all samples and the predominance of low molecular weight congeners indicate that there are no significant local PCBs sources in the area of study.

  14. Influence of polychlorinated biphenyls on the growth of chicken embryos

    SciTech Connect

    Hatano, Yasuhiko; Hatano, Akira

    1994-12-31

    Incubation of chicken embryos with either 0.01 or 0.03 ppm polychlorinated biphenyls (PCBs) for 12, 15, or 18 d resulted in a significant decrease in liver and body weight associated with enhanced mortality. Teratological examination revealed an increased frequency of malformations including hydrops, eventration, wry neck, and brevicollis. PCB exposure was also found to produce histologic damage to liver and cutaneous tissue. Our data demonstrate that exposure of chicks to PCBs during development results in a retardation of growth, an increased incidence of malformations, and histopathologic damage. 9 refs., 2 figs., 4 tabs.

  15. Isolation and characterization of bacteria degrading polychlorinated biphenyls from transformer oil.

    PubMed

    Rojas-Avelizapa, N G; Rodríguez-Vázquez, R; Martínez-Cruz, J; Esparza-García, F; Montes de Oca-García, A; Ríos-Leal, E; Fernández-Villagómez, G

    1999-01-01

    Polychlorinated biphenyls from transformer oil were degraded in liquid culture under aerobic conditions using a mixed bacterial culture isolated from a transformer oil sample with a high content of polychlorinated biphenyls and other hydrocarbons. Four strains were identified, three of them corresponded to genus Bacillus, the other one to Erwinia. Bacteria in the transformer oil could remove as much as 65% of polychlorinated biphenyls (88% W/V in the transformer oil). Additional data showed that the two isolated strains of B. lentus were able to grow on transformer oil and degrade polychlorinated biphenyls by 80 and 83%. Our results provide evidence that microorganisms occurring in transformer oil have the potential to degrade polychlorinated biphenyls.

  16. Oxidation of biphenyl by a multicomponent enzyme system from Pseudomonas sp. strain LB400.

    PubMed Central

    Haddock, J D; Nadim, L M; Gibson, D T

    1993-01-01

    Pseudomonas sp. strain LB400 grows on biphenyl as the sole carbon and energy source. This organism also cooxidizes several chlorinated biphenyl congeners. Biphenyl dioxygenase activity in cell extract required addition of NAD(P)H as an electron donor for the conversion of biphenyl to cis-2,3-dihydroxy-2,3-dihydrobiphenyl. Incorporation of both atoms of molecular oxygen into the substrate was shown with 18O2. The nonlinear relationship between enzyme activity and protein concentration suggested that the enzyme is composed of multiple protein components. Ion-exchange chromatography of the cell extract gave three protein fractions that were required together to restore enzymatic activity. Similarities with other multicomponent aromatic hydrocarbon dioxygenases indicated that biphenyl dioxygenase may consist of a flavoprotein and iron-sulfur proteins that constitute a short electron transport chain involved in catalyzing the incorporation of both atoms of molecular oxygen into the aromatic ring. Images PMID:8419290

  17. Biphenyl-Metabolizing Bacteria in the Rhizosphere of Horseradish and Bulk Soil Contaminated by Polychlorinated Biphenyls as Revealed by Stable Isotope Probing▿ †

    PubMed Central

    Uhlik, Ondrej; Jecna, Katerina; Mackova, Martina; Vlcek, Cestmir; Hroudova, Miluse; Demnerova, Katerina; Paces, Vaclav; Macek, Tomas

    2009-01-01

    DNA-based stable isotope probing in combination with terminal restriction fragment length polymorphism was used in order to identify members of the microbial community that metabolize biphenyl in the rhizosphere of horseradish (Armoracia rusticana) cultivated in soil contaminated with polychlorinated biphenyls (PCBs) compared to members of the microbial community in initial, uncultivated bulk soil. On the basis of early and recurrent detection of their 16S rRNA genes in clone libraries constructed from [13C]DNA, Hydrogenophaga spp. appeared to dominate biphenyl catabolism in the horseradish rhizosphere soil, whereas Paenibacillus spp. were the predominant biphenyl-utilizing bacteria in the initial bulk soil. Other bacteria found to derive carbon from biphenyl in this nutrient-amended microcosm-based study belonged mostly to the class Betaproteobacteria and were identified as Achromobacter spp., Variovorax spp., Methylovorus spp., or Methylophilus spp. Some bacteria that were unclassified at the genus level were also detected, and these bacteria may be members of undescribed genera. The deduced amino acid sequences of the biphenyl dioxygenase α subunits (BphA) from bacteria that incorporated [13C]into DNA in 3-day incubations of the soils with [13C]biphenyl are almost identical to that of Pseudomonas alcaligenes B-357. This suggests that the spectrum of the PCB congeners that can be degraded by these enzymes may be similar to that of strain B-357. These results demonstrate that altering the soil environment can result in the participation of different bacteria in the metabolism of biphenyl. PMID:19700551

  18. Maternal exposure to polychlorinated biphenyls and the secondary sex ratio: an occupational cohort study

    PubMed Central

    2011-01-01

    Background Though commercial production of polychlorinated biphenyls was banned in the United States in 1977, exposure continues due to their environmental persistence. Several studies have examined the association between environmental polychlorinated biphenyl exposure and modulations of the secondary sex ratio, with conflicting results. Objective Our objective was to evaluate the association between maternal preconceptional occupational polychlorinated biphenyl exposure and the secondary sex ratio. Methods We examined primipara singleton births of 2595 women, who worked in three capacitor plants at least one year during the period polychlorinated biphenyls were used. Cumulative estimated maternal occupational polychlorinated biphenyl exposure at the time of the infant's conception was calculated from plant-specific job-exposure matrices. A logistic regression analysis was used to evaluate the association between maternal polychlorinated biphenyl exposure and male sex at birth (yes/no). Results Maternal body mass index at age 20, smoking status, and race did not vary between those occupationally exposed and those unexposed before the child's conception. Polychlorinated biphenyl-exposed mothers were, however, more likely to have used oral contraceptives and to have been older at the birth of their first child than non-occupationally exposed women. Among 1506 infants liveborn to polychlorinated biphenyl-exposed primiparous women, 49.8% were male; compared to 49.9% among those not exposed (n = 1089). Multivariate analyses controlling for mother's age and year of birth found no significant association between the odds of a male birth and mother's cumulative estimated polychlorinated biphenyl exposure to time of conception. Conclusions Based on these data, we find no evidence of altered sex ratio among children born to primiparous polychlorinated biphenyl-exposed female workers. PMID:21418576

  19. Reevaluation of polychlorinated biphenyl concentrations in milk and body fat of lactating cows.

    PubMed

    Willett, L B; Liu, T T; Fries, G F

    1990-08-01

    Polychlorinated biphenyls occur as mixtures of congeners, each of which may be absorbed, excreted, or metabolized differently. Quantification of polychlorinated biphenyls by packed-column GLC has been difficult. Many quantification techniques, generally based on quantification of a selected group of the congeners present, have been used by researchers. Results of these studies have not provided a consistent basis to determine the relationship between the amounts of polychlorinated biphenyls consumed and residual polychlorinated biphenyls in milk and animal tissues. In the present study, we hypothesized that if a standardized quantification procedure was applied, consistent dose:residue predictions could be made. Weighted percentage of each peak in the polychlorinated biphenyl mixture procedures was used as a standard method to quantify polychlorinated biphenyls in milk fat from published and unpublished studies where lactating cows were fed between 3.5 and 1000 mg/d (Aroclor 1254) for greater than or equal to 15 d. When steady state occurred by 60 d of dosing, the relationship between concentration in milk fat (microgram/g) and daily dose as mg and as mg/kg BW were described by the equations: [polychlorinated biphenyls, microgram/g]milk fat = .28 (daily dose, mg).82, and [polychlorinated biphenyls, microgram/g]milk fat = 50.2 (daily dose, mg/kg BW).81. Similar equations described the relationships between daily dose and concentrations in adipose tissue and blood plasma. Concentrations of polychlorinated biphenyls residues in milk fat of 79 animals that were dosed with known quantities of polychlorinated biphenyls for 15 to 107 d confirmed that the equations could be valuable in predicting exposure over a wide range of exposure durations and concentrations.

  20. Semipermeable membrane devices used to estimate bioconcentration of polychlorinated biphenyls

    USGS Publications Warehouse

    Chambers, D.B.

    1999-01-01

    Aquatic organisms passively accumulate hydrophobic organic compounds, such as polychlorinated biphenyls, even when ambient water concentrations of the contaminant are below analytical detection limits. However, contaminant concentrations in tissue samples are subject to an inherently high level of variability due to differences in species, life stage, and gender bioconcentration potentials. Semipermeable membrane devices (SPMDs) were used to sample Aroclor 1254, a mixture of readily bioconcentrated polychlorinated biphenyls (PCBs), in a contaminated wetland near Flat Top, WV. The devices consisted of triolein, a lipid found in fish, enclosed in a polyethylene membrane. SPMDs were deployed in the water column and in direct contact with wetland sediments along a previously identified concentration gradient of PCBs. The devices were retrieved after a 25-day exposure period. Analytes were recovered by dialyzing the devices in nanograde hexane. Hexane dialysates were condensed and analyzed by gas chromatography. All deployed devices sequestered quantifiable amounts of Aroclor 1254. Water-column SPMDs accumulated PCBs far in excess of ambient water concentrations. The devices contacting sediments accumulated PCBs at all sites, though accumulated concentrations did not exceed concentrations in sediment. Patterns of PCB concentration in the devices corresponded to the identified gradient at the site. Results from the water-column SPMDs were used to estimate the concentration of the dissolved, bioavailable fraction of PCBs present in the water column. These concentrations ranged from 0.01 to 0.09 ??g/L of bioavailable Aroclor 1254.

  1. Biobatteries and biofuel cells with biphenylated carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Stolarczyk, Krzysztof; Kizling, Michał; Majdecka, Dominika; Żelechowska, Kamila; Biernat, Jan F.; Rogalski, Jerzy; Bilewicz, Renata

    2014-03-01

    Single-walled carbon nanotubes (SWCNTs) covalently biphenylated are used for the construction of cathodes in a flow biobattery and in flow biofuel cell. Zinc covered with a hopeite layer is the anode in the biobattery and glassy carbon electrode covered with bioconjugates of single-walled carbon nanotubes with glucose oxidase and catalase is the anode of the biofuel cell. The potentials of the electrodes are measured vs. the Ag/AgCl reference electrode under changing loads of the fuel cell/biobattery. The power density of the biobattery with biphenylated nanotubes at the cathode is ca. 0.6 mW cm-2 and the open circuit potential is ca. 1.6 V. In order to obtain larger power densities and voltages three biobatteries are connected in a series which leads to the open circuit potential of ca. 4.8 V and power density 2.1 mW cm-2 at 3.9 V under 100 kΩ load. The biofuel cell shows power densities of ca. 60 μW cm-2 at 20 kΩ external resistance but the open circuit potential for such biofuel cell is only 0.5 V. The biobattery showing significantly larger power densities and open circuit voltages are especially useful for testing novel cathodes and applications such as powering units for clocks and sensing devices.

  2. Momentum space analysis of the electronic structure of biphenyl

    NASA Astrophysics Data System (ADS)

    Morini, F.; Shojaei, S. H. Reza; Deleuze, M. S.

    2014-11-01

    The results of a yet to come experimental study of the electronic structure of biphenyl employing electron momentum spectroscopy (EMS) have been theoretically predicted, taking into account complications such as structural mobility in the electronic ground state, electronic correlation and relaxation, and a dispersion of the inner-valence ionization intensity to electronically excited (shake-up) configurations in the cation. The main purpose of this work is to explore the current limits of EMS in unraveling details of the molecular structure, namely the torsional characteristics of large and floppy aromatic molecules. At the benchmark ADC(3)/cc-pVDZ level of theory, the influence of the twist angle between the two phenyl rings is found to be extremely limited, except for individual orbital momentum profiles corresponding to ionization lines at electron binding energies ranging from 15 to 18 eV. When taking band overlap effects into account, this influence is deceptively far too limited to allow for any experimental determination of the torsional characteristics of biphenyl by means of EMS.

  3. Fungal laccase-catalyzed degradation of hydroxy polychlorinated biphenyls.

    PubMed

    Keum, Young Soo; Li, Qing X

    2004-07-01

    Hydroxy polychlorinated biphenyls (hydroxy PCBs) are toxic metabolites of PCBs. Their toxicity such as strong endocrine disruption demands effective remediation methods. Laccases from Trametes versicolor and Pleurotus ostreatus were tested to degrade hydroxy PCBs. Optimum pHs for both enzymes were around 4.0. Laccase from T. versicolor degrades hydroxy PCBs more rapidly than that from P. ostreatus. The enzymatic activities remained little changes in up to 10% organic solvents, but decreased rapidly in more than 10% acetone, acetonitrile or DMSO. Degradation rate constants decreased with increase of chlorination and no degradation was observed with tetra-, penta- and hexa-chloro hydroxy PCBs in non-mediated reactions. However, the tetra- to hexa-chloro hydroxy PCBs were degraded by laccase from T. versicolor in the presence of the mediator 2,2,6,6-tetramethylpiperidine-N-oxy radical. The other mediators, 4-ethyl-2-methoxyphenol, 2,2'-azino-bis(3-ethylbenzthiazoline sulfonic acid) diammonium salt and 1-hydroxybenzotriazole and humic acid, also enhanced degradation of all the hydroxy PCBs except 4-hydroxy-2',3,3',4',5,5'-hexachlorobiphenyl. The results showed that 3-hydroxy biphenyl was more resistant to laccase degradation than 2- or 4-hydroxy analogues. Significant linear-correlations (coefficient of determination, r2 = 0.9097 and 0.8186 for laccases from P. ostreatus and T. versicolor, respectively) were found between the ionization potentials and the removal rate constants of hydroxy PCBs.

  4. Aryl biphenyl-3-ylmethylpiperazines as 5-HT7 receptor antagonists.

    PubMed

    Kim, Jeeyeon; Kim, Youngjae; Tae, Jinsung; Yeom, Miyoung; Moon, Bongjin; Huang, Xi-Ping; Roth, Bryan L; Lee, Kangho; Rhim, Hyewhon; Choo, Il Han; Chong, Youhoon; Keum, Gyochang; Nam, Ghilsoo; Choo, Hyunah

    2013-11-01

    The 5-HT7 receptor (5-HT7 R) is a promising therapeutic target for the treatment of depression and neuropathic pain. The 5-HT7 R antagonist SB-269970 exhibited antidepressant-like activity, whereas systemic administration of the 5-HT7 R agonist AS-19 significantly inhibited mechanical hypersensitivity and thermal hyperalgesia. In our efforts to discover selective 5-HT7 R antagonists or agonists, aryl biphenyl-3-ylmethylpiperazines were designed, synthesized, and biologically evaluated against the 5-HT7 R. Among the synthesized compounds, 1-([2'-methoxy-(1,1'-biphenyl)-3-yl]methyl)-4-(2-methoxyphenyl)piperazine (28) was the best binder to the 5-HT7 R (pKi =7.83), and its antagonistic property was confirmed by functional assays. The selectivity profile of compound 28 was also recorded for the 5-HT7 R over other serotonin receptor subtypes, such as 5-HT1 R, 5-HT2 R, 5-HT3 R, and 5-HT6 R. In a molecular modeling study, the 2-methoxyphenyl moiety attached to the piperazine ring of compound 28 was proposed to be essential for the antagonistic function.

  5. A reassessment of the nomenclature of polychlorinated biphenyl (PCB) metabolites.

    PubMed Central

    Maervoet, Johan; Covaci, Adrian; Schepens, Paul; Sandau, Courtney D; Letcher, Robert J

    2004-01-01

    Polychlorinated biphenyls (PCBs) are a widespread class of persistent organic chemicals that accumulate in the environment and humans and are associated with a broad spectrum of health effects. PCB biotransformation has been shown to lead to two classes of PCB metabolites that are present as contaminant residues in the tissues of selected biota: hydroxylated (HO) and methyl sulfone (MeSO2) PCBs. Although these two types of metabolites are related structures, different rules for abbreviation of both classes have emerged. It is important that a standardized nomenclature for the notation of PCB metabolites be universally agreed upon. We suggest that the full chemical name of the PCB metabolite and a shorthand notation should be adopted using the International Union of Pure and Applied Chemistry's chemical name/original Ballschmiter and Zell number of the parent congener, followed by the assignment of the phenyl ring position number of the MeSO2- or HO-substituent. This nomenclature provides a clear, unequivocal set of rules in naming and abbreviating the PCB metabolite structure. Furthermore, this unified PCB metabolite nomenclature approach can be extended to the naming and abbreviation of potential metabolites of structurally analogous contaminants such as HO-polybrominated biphenyls and HO-polybrominated diphenyl ethers. PMID:14998742

  6. Diversity of chlorobiphenyl-metabolizing bacteria and their biphenyl dioxygenases in contaminated sediment.

    PubMed

    Koubek, Jiri; Mackova, Martina; Macek, Tomas; Uhlik, Ondrej

    2013-11-01

    Bacteria and bacterial communities in sites contaminated with polychlorinated biphenyls have been extensively studied in the past decades. However, there are still major gaps in the knowledge of environmental processes, especially in the behavior of previously described bacteria in vitro, their real degradation abilities and the enzymes that are involved in the degradation processes. In this work we analyzed actively degrading bacterial populations by stable isotope probing with (13)C biphenyl and (13)C-4-chlorobiphenyl as labeled substrates in the environment of sediment contaminated with polychlorinated biphenyls. We performed analysis of populations which degrade biphenyl and 4-chlorobiphenyl at concentrations similar to those of the original site. Several bacterial genera were revealed to actively participate in biphenyl and 4-chlorobiphenyl removal, some of which had not previously been described to take part in this process. We also found there are few differences in the communities metabolizing biphenyl and 4-chlorobiphenyl. Analysis of the genes responsible for substrate removal proved most of the genes to be closely related to Pseudomonas pseudoalcaligenes KF707 genes giving bacteria the ability of transforming di-para-chlorinated biphenyls. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  7. 4-Substituted-2-Methoxyphenol: Suitable Building Block to Prepare New Bioactive Natural-like Hydroxylated Biphenyls

    PubMed Central

    Dettori, Maria Antonietta; Fabbri, Davide; Pisano, Marina; Rozzo, Carla; Palmieri, Giuseppe; Dessµ, Alessandro; Dallocchio, Roberto; Delogu, Giovanna

    2015-01-01

    A small collection of eugenol- and curcumin-analog hydroxylated biphenyls was prepared by straightforward methods starting from natural 4-substituted-2-methoxyphenols and their antitumoral activity was evaluated in vitro. Two curcumin-biphenyl derivatives showed interesting growth inhibitory activities on different malignant melanoma cell lines with IC50 ranging from 13 to 1 µM. Preliminary molecular modeling studies were carried out to evaluate conformations and dihedral angles suitable for antiproliferative activity in hydroxylated biphenyls bearing a side aliphatic chain. PMID:26074750

  8. Determination of acute toxicity of polychlorinated biphenyls to photobactrium phosphoreum

    SciTech Connect

    Chu, S.; Xu, X.; He, Y.

    1997-02-01

    Polychlorinated biphenyls (PCBs) are a highly lipophilic group of global pollutants, consisting of 209 congeners. PCBs were discovered before the turn of the century and their usefulness for industry, because of their physical properties, was recognized early. The distribution of PCBs in the environment was not noticed until Jensen and his colleagues found PCBs in wildlife samples. Since then, investigations in many parts of the world have revealed the widespread distribution of PCBs in environmental samples and PCVs are persistent and accumulate in food webs. Thus, determination of toxicities of commercial PCB mixtures and PCB congeners are required. Toxicity tests using luminous bacteria have shown high correlation to traditional bioassays. This study compared the EC50 values of the commercial mixtures, PCB3 and PCB5, with those of Aroclor 1242 and Aroclor 1254. 12 refs., 2 tabs.

  9. Polychlorinated Biphenyl Sorption and Availability in Field-Contaminated Sediments†

    PubMed Central

    2009-01-01

    Traditional and new relationships of polychlorinated biphenyl (PCB) distribution among the solid phases, the free aqueous phase, and biolipids are comprehensively reviewed using seven well-characterized freshwater and marine sediments polluted with PCBs. The traditional relationship relating free aqueous concentration and biolipid concentration to sediment total organic carbon, compound octanol−water partitioning coefficient, and solid-phase contaminant concentration overestimates measured free aqueous concentrations and biolipid concentrations by mean factors of 8 and 33, respectively. By contrast, relationships based on measured free aqueous phase concentrations or the PCB mass fraction desorbed from sediment provide reasonable predictions of biolipid concentrations. Solid-phase concentration-based predictions perform better when sorption to amorphous organic matter and black carbon (BC) is distinguished. Contrary to previously published relationships, BC sorption appears to be linear for free aqueous PCB-congener concentrations in the picogram to microgram per liter range. PMID:19961220

  10. Polychlorinated Biphenyls as Probes of Biogeochemical Processes in Rivers

    USGS Publications Warehouse

    Fitzgerald, S.A.; Steuer, J.J.

    1997-01-01

    A field study was conducted to investigate the use of PCB (polychlorinated biphenyl) congener and homolog assemblages as tracers of biogeochemical processes in the Milwaukee and Manitowoc Rivers in southeastern Wisconsin from 1993 to 1995. PCB congeners in the dissolved and suspended particle phases, along with various algal indicators (algal carbon and pigments), were quantitated in the water seasonally. In addition, PCB congener assemblages were determined seasonally in surficial bed sediments. Biogeochemical processes investigated included: determination of the source of suspended particles and bottom sediments by comparison with known Aroclor mixtures, water-solid partitioning, and algal uptake of PCBs. Seasonal differences among the PCB assemblages were observed mainly in the dissolved phase, somewhat less in the suspended particulate phase, and not at all in the bed sediments.

  11. Donor's position-specific channel interference in substituted biphenyl molecules.

    PubMed

    Mehboob Alam, Md

    2015-07-21

    The channel interference mechanism describes the two-photon absorption process in terms of the relative orientations of different transition dipole moment vectors (TDMVs) in a molecule. Controlling these interferences is a difficult but important task, because it can provide new information about such absorption/emission processes. The present contribution aims to explain the reversal in the nature of these interferences with the relative positions of the donor-acceptor groups in substituted biphenyl molecules. The results obtained from the linear and quadratic response theories indicate that having the donor at the para position leads to a constructive interference whereas having it at any of the other two positions results in a destructive interference. This is explained by a systematic analysis of the relative orientations of all the TDMVs involved in a three-state model.

  12. Integration of sample analysis method (SAM) for polychlorinated biphenyls

    SciTech Connect

    Monagle, M.; Johnson, R.C.

    1996-05-01

    A completely integrated Sample Analysis Method (SAM) has been tested as part of the Contaminant Analysis Automation program. The SAM system was tested for polychlorinated biphenyl samples using five Standard Laboratory Modules{trademark}: two Soxtec{trademark} modules, a high volume concentrator module, a generic materials handling module, and the gas chromatographic module. With over 300 samples completed within the first phase of the validation, recovery and precision data were comparable to manual methods. Based on experience derived from the first evaluation of the automated system, efforts are underway to improve sample recoveries and integrate a sample cleanup procedure. In addition, initial work in automating the extraction of semivolatile samples using this system will also be discussed.

  13. Effects of polychlorinated biphenyls on development and reproduction.

    PubMed

    Faroon, O M; Keith, S; Jones, D; de Rosa, C

    2001-04-01

    As part of its mandate, the Agency for Toxic Substances and Disease Registry (ATSDR) prepares toxicological profiles on hazardous chemicals found at Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) National Priorities List (NPL) sites that have the greatest public health impact. These profiles comprehensively summarize toxicological and environmental information. This article, which constitutes the release of an important section of the Toxicological Profile for Polychlorinated Biphenyls (ATSDR 2000) into the scientific literature, focuses on the developmental and reproductive effects of this group of synthetic organic chemicals (PCBs) in humans and animals. Information on other health effects, toxicokinetics, mechanisms of toxicity, biomarkers, interactions, chemical and physical properties, potential for human exposure, and regulations and advisories is detailed in the profile. Interested readers are encouraged to consult the original toxicological profile for more information. Profiles can be requested from ATSDR's Information Center by telephone (1-888-42-ATSDR [1-888-422-8737] or E-mail: (atsdric@cdc.gov).

  14. Developmental neurotoxicology of polychlorinated biphenyls and related compounds

    SciTech Connect

    Tilson, H.A.; Harry, G.J.

    1992-01-01

    Polychlorinated biphenyls are stable, lipophilic industrial compounds that are present in residue levels in human tissue, wildlife and freshwater sediment. They are toxic and are known to pass the placenta and intoxicate the fetus. Two large outbreaks of poisoning have occurred in Asia and women pregnant at or after the exposures had children who were developmentally impaired. Laboratory experiments in rhesus monkeys and rodents designed to assess neural or developmental neurotoxic effects show altered activity levels, impaired learning, and delayed ontogeny of reflexes. Children exposed transplacentally to PCBs in North America have been reported to display hypotonia and hyporeflexia at birth, delay in psychomotor development at 6 and 12 months of age and poorer visual recognition at 7 months. PCBs appear to be developmental neurotoxicants in both humans and animals and may pose a significant health risk, particularly to pregnant women and their offspring.

  15. Bis(4-carbamoylpiperidinium) biphenyl-4,4′-disulfonate

    PubMed Central

    Smith, Graham; Wermuth, Urs D.; Young, David J.

    2010-01-01

    In the title isonipecotamide salt 2C6H13N2O+·C12H8O6S2 2−, the asymmetric unit comprises one biphenyl-4,4′-disulfonate dianion which lies across a crystallographic inversion centre and another in a general position [dihedral angle between the two phenyl rings is 37.1 (1)°], together with three isonipecotamide cations. Two of these cations give a cyclic homomeric amide–amide dimer inter­action [graph set R 2 2(8)], the other giving a similar dimeric inter­action but across an inversion centre, both dimers then forming lateral cyclic R 4 2(8) pyrimidinium–amide N—H⋯O inter­actions. These units are linked both laterally and longitudinally to the sulfonate groups of the dianions through piperidinium N—H⋯O hydrogen bonds, giving a three-dimensional framework structure. PMID:21589457

  16. Polychlorinated biphenyls and organochlorine pesticides in plastics ingested by seabirds.

    PubMed

    Colabuono, Fernanda Imperatrice; Taniguchi, Satie; Montone, Rosalinda Carmela

    2010-04-01

    The occurrence of plastic objects in the digestive tract was assessed in eight species of Procellariiformes collected in southern Brazil and the occurrence of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in the ingested plastics pellets and plastic fragments was evaluated. PCBs were detected in plastic pellets (491 ng g(-1)) and plastic fragments (243-418 ng g(-1)). Among the OCPs, p,p'-DDE had the highest concentrations, ranging from 68.0 to 99.0 ng g(-1). The occurrence of organic pollutants in post-consumer plastics supports the fact that plastics are an important source carrying persistent organic pollutants in the marine environment. Although transfer through the food chain may be the main source of exposure to POPs to seabirds, plastics could be an additional source for the organisms which ingest them, like Procellariiformes which are the seabirds most affected by plastic pollution. (c) 2010 Elsevier Ltd. All rights reserved.

  17. Phase Pinning by EPR Probe in Biphenyl Doped with Naphthalene

    NASA Astrophysics Data System (ADS)

    Veron, A.; Emery, J.

    1997-08-01

    The naphthalene Electronic Paramagnetic Resonance probe used to study the phase transitions in biphenyl does not account for the plane wave modulation of the incommensurate phase II. Its EPR spectra yields a phase distribution which looks like a “multi-soliton regime”. Moreover, the splitting between the edge singularities is not symmetrical, in contradiction with a linear one. This behaviour is not exhibited by the phenanthrene EPR probe whose spectra account well enough for the plane wave modulation with a linear coupling to the order parameter. To analyse the defect behaviour of the probe, we first introduce a coupling between the probe and the modulation wave and determine the phase distribution within the phenomenological Landau theory. Furthermore, a calculation based on intermolecular interaction is performed in order to describe the microscopic origin of this distribution and is applied to naphthalene and phenanthrene molecular probes.

  18. Polychlorinated biphenyls in the Great Lakes: 1990`s concentrations

    SciTech Connect

    Bloem, T.B.; Stanko, T.A.; Blankenbaker, R.K.; Higgins, J.H.; De Vault, D.S.; Anderson, D.J.

    1994-12-31

    Concentrations of polychlorinated biphenyls (PCBs) in the water column of the Laurentian Great Lakes have declined over the last decade. The measurement of current concentrations of these hydrophobic organic contaminants (HOCS) requires the sampling of large sample volumes, typically 100--400 liters. This paper will present results from the water column HOC trend program, begun by GLNPO in 1991. Water samples were filtered with a 0.7{mu}M glass fiber filter, and the filtrate was collected and extracted using the Goulden Large Sample Extractor (GLSE). PCBs were extracted from the filters with Soxhlet extraction, and the resulting operationally-defined particulate and dissolved phases were analyzed by gas chromatography with electron capture detection. Results indicate concentrations in the 100s of picograms/liter for total PCBs. Spatial differences within and between Lakes, and temporal differences will be presented.

  19. Polychlorinated biphenyl transport in the Hudson River, New York

    USGS Publications Warehouse

    Turk, John T.; Troutman, David E.

    1981-01-01

    Polychlorinated biphenyls (PCB's) have been entering the Hudson River estuary since 1951. Concentration and loading of PCB 's in the river below Waterford, N.Y., are controlled at present by resuspension of sediments containing these substances; therefore , until the amount of PCB 's in the sediments is significantly lowered, reduction of point-source PCB discharge from the present rate of 0.4 kilograms per day will produce no more than a 10% reduction in loading to the river. Potential concentrations of PCB 's in solution and suspension in the river can be predicted by a simple model for mixing and dilution. From a known range of PCB influent rates, total PCB loading to the Hudson River from above Waterford is shown to be between 2,000 and 12,000 kilograms per year. (USGS)

  20. Column chromatography separation of polychlorinated biphenyls from dichlorodiphenyltrichloroethane and methabolites

    SciTech Connect

    Needham, L.L.; Smrek, A.L.; Head, S.L.; Burse, V.W.; Liddle, J.A.

    1980-11-01

    Gas chromatographic determinations of organochlorine insectides or polychlorinated biphenyls (PCBs) in biological material are often complicated by their simultaneous presence in the eluates from the column chromatography steps. A gas chromatography/electron capture detector procedure to analyze serum for PCBs (Aroclor 1260) in the presence of the ortho, para and para, para isomers of dichlorodiphenyltrichloroethane (DDT) and its metabolites, dichlorodiphenyldichloroethylene (DDE) and dichlorodiphenyldichloroethane (DDD) was devised. The use of silver nitrate on silica gel column to separate PCBs from DDT and metabolites are described. Bovine serum was analyzed for DDt, DDE, and DDD. 500 individuals in an Alabama community were studied, the highest concentrations in (ppB) for PCB was 155. The method described yield high recoveries of PCBs, with no interference from chlorinated hydrocarbons normally found in human serum. 2 figures, 2 tables. (DP)

  1. Polychlorinated biphenyl partitioning and bioaccumulation in Green Bay, Lake Michigan

    SciTech Connect

    Endicott, D.; Griesmer, D.; Kreis, R.; Mackelburg, L.

    1994-12-31

    The 1989--1990 Green Bay Mass Balance Study generated an extensive data set for polychlorinated biphenyl (PCB) congeners in water, sediment and biological matrices. The analytes included several mono-ortho substituted PCB congeners. From these data, ratios between dissolved, particulate, and biotic concentrations in the water column and sediment have been calculated. These ratios provide a basis for evaluating the distribution of hydrophobic organic chemicals in the aquatic ecosystem. The Mass Balance Study also supported development of mathematical models of PCB transport, fate, and food chain bioaccumulation in Green Bay. The models provide significant additional insight as to processes affecting the observed PCB distribution, including spatial-temporal variability, organic carbon sorbent dynamics, sediment-water column disequilibria, and kinetics of bioaccumulation.

  2. Cleaning Polychlorinated Biphenyl (PCB) Contaminated Garden Soil by Phytoremediation

    PubMed Central

    Schnoor, Jerald L.

    2013-01-01

    A poplar planted system resulted in the complete removal of at least 19 of the 29 potential polychlorinated biphenyl (PCB) congeners detected in trace amounts (37.9 ng g-1 in total) in a commercial garden soil, while the unplanted soil only had 2 congeners completely removed after 96 days. In addition, the most recalcitrant congener, PCB 52, only decreased by 0.1% in the unplanted reactors while declining by 22.3% in the planted system. There was also greater removal of a PCB 77 spike in the planted system when compared to the unplanted system, 17.2% in the planted system versus 2.8% in the unplanted system. The results suggest that phytoremediation may be an effective tool in cleaning commercially available garden soils that are lightly contaminated with PCBs. PMID:24409084

  3. Polychlorinated biphenyl accumulation in tree bark and wood growth rings

    SciTech Connect

    Meredith, M.L.; Hites, R.A.

    1987-07-01

    Polychlorinated biphenyls (PCBs) were found in the bark of black walnut and tulip poplar trees growing near a PCB-contaminated landfill. PCBs were also found in the bark of white oak trees growing 14 km away from the landfill. The concentration of individual congeners in the bark averaged 18 ppb at the landfill and 0.5 ppb at the other site. The PCB congeners were accumulated into the bark in proportion to their lipophilicity (as measured by octanol-water partition coefficients). The authors findings suggest that tree bark could be used for biomonitoring of lipophilic organic pollutants in the atmosphere. There is little evidence that PCBs are present in the wood of trees. The signal to blank ratios are always less than 3, and the relative concentrations between 20-year time intervals do not show trends that correlate with the known inputs of PCBs in Bloomington, IN. 2 tables.

  4. Hydroxylated polychlorinated biphenyls in the environment: sources, fate, and toxicities.

    PubMed

    Tehrani, Rouzbeh; Van Aken, Benoit

    2014-05-01

    Hydroxylated polychlorinated biphenyls (OH-PCBs) are produced in the environment by the oxidation of PCBs through a variety of mechanisms, including metabolic transformation in living organisms and abiotic reactions with hydroxyl radicals. As a consequence, OH-PCBs have been detected in a wide range of environmental samples, including animal tissues, water, and sediments. OH-PCBs have recently raised serious environmental concerns because they exert a variety of toxic effects at lower doses than the parent PCBs and they are disruptors of the endocrine system. Although evidence about the widespread dispersion of OH-PCBs in various compartments of the ecosystem has accumulated, little is currently known about their biodegradation and behavior in the environment. OH-PCBs are, today, increasingly considered as a new class of environmental contaminants that possess specific chemical, physical, and biological properties not shared with the parent PCBs. This article reviews recent findings regarding the sources, fate, and toxicities of OH-PCBs in the environment.

  5. Phytoremediation of Polychlorinated Biphenyls: New Trends and Promises

    PubMed Central

    Van Aken, Benoit; Correa, Paola A.; Schnoor, Jerald L.

    2011-01-01

    Transgenic plants and associated bacteria constitute a new generation of genetically modified organisms for efficient and environmental-friendly treatment of soil and water contaminated with polychlorinated biphenyls (PCBs). This review focuses on recent advances in phytoremediation for the treatment of PCBs, including the development of transgenic plants and associated bacteria. Phytoremediation, or the use of higher plants for rehabilitation of soil and groundwater, is a promising strategy for cost-effective treatment of sites contaminated by toxic compounds, including toxic PCBs. Plants can help mitigate environmental pollution by PCBs through a range of mechanisms: besides uptake from soil (phytoextraction), plants are capable of enzymatic transformation of PCBs (phytotransformation); by releasing a variety of secondary metabolites, plants also enhance the microbial activity in the root zone, improving biodegradation of PCBs (rhizoremediation). However, because of their hydrophobicity and chemical stability, PCBs are only slowly taken up and degraded by plants and associated bacteria, resulting in incomplete treatment and potential release of toxic metabolites into the environment. Moreover, naturally occurring plant-associated bacteria may not possess the enzymatic machinery necessary for PCB degradation. In order to overcome these limitations, bacterial genes involved in the metabolism of PCBs, such as biphenyl dioxygenases, have been introduced into higher plants, following a strategy similar to the development of transgenic crops. Similarly, bacteria have then been genetically modified that exhibit improved biodegradation capabilities and are able to maintain stable relationships with plants. Transgenic plants and associated bacteria bring hope for a broader and more efficient application of phytoremediation for the treatment of PCBs. PMID:20384372

  6. Risk of Spontaneous Abortion among Women Exposed to Polybrominated Biphenyls

    PubMed Central

    Small, Chanley M.; Cheslack-Postava, Keely; Terrell, Metrecia; Blanck, Heidi Michels; Tolbert, Paige; Rubin, Carol; Henderson, Alden; Marcus, Michele

    2008-01-01

    Accidental contamination of livestock in Michigan in 1973 with polybrominated biphenyls (PBBs) led to the establishment of a registry of exposed individuals in 1976. At the time of enrollment, serum was collected and analyzed for PBBs and polychlorinated biphenyls, PCBs. In 1997, women aged 18 years or older and active in the registry were invited to participate in a telephone interview about their health. Using generalized estimating equations to account for correlated outcomes within the same woman, we assessed the risk of spontaneous abortion among 529 women with 1344 potentially exposed pregnancies. PBB and PCB exposure were not associated with risk of spontaneous abortion after adjusting for maternal age at conception, age at menarche, and prior infertility. Compared to pregnancies with PBB exposure below the limit of detection, those with levels above 2.9 ppb had a non-significant reduced odds of spontaneous abortion (adjusted OR=0.73; 95% CI= 0.47-1.13). Compared to pregnancies with PCB exposure below the limit of detection, those with levels above 6.5 ppb had little difference in risk (adjusted OR=0.91; 95% CI= 0.59-1.41). Maternal age at conception above 34 years was significantly associated with elevated risk of spontaneous abortion (OR=2.46; 95% CI= 1.10-5.49). The effect of prior infertility was of borderline significance (OR=1.52; 95% CI= 0.98-2.38). Older age at menarche was associated with decreased risk of spontaneous abortion (adjusted OR=0.58; 95% CI: 0.38-0.89, comparing menarche at 12-13 with menarche <12). Our results do not support an association between exposure to PBBs or PCBs and risk of spontaneous abortion. PMID:17239850

  7. Guidance on the management of polychlorinated biphenyls (PCBs)

    SciTech Connect

    Not Available

    1993-11-01

    Polychlorinated biphenyls (PCBs) are a class of synthetic organic chemicals including 209 known isomers, each with from 1 to 10 chlorine atoms on a biphenyl ring. PCBs have a number of desirable properties for industrial applications including thermal stability, flame retardance, and low vapor pressure. Because of these properties, PCBs were widely used as dielectric fluid in electrical equipment such as utility transformers and capacitors. PCBs were also extensively used in hydraulic fluid and heat transfer fluid, in gaskets, as additives in cutting oils and lubricant, and in a variety of other uses. The Toxic Substances Control Act (TSCA) banned the manufacture of PCBs after 1978 in response to emerging information about the adverse health effects of PCBs and their persistence in the environment. In addition, TSCA directed the Administrator of the Environmental Protection Agency (EPA) to prescribe methods for disposal of PCBS, require marking of PCBs with warning labels, and control their use. The TSCA regulations allow continued use of PCBs provided that the use is totally enclosed and does not pose a risk to human health or the environment. However, at the end of their useful life, all PCB materials must be disposed of according to the TSCA regulations. This guidance document uses graphics and flow charts where possible to present the TSCA regulations according to management activities such as use, storage, disposal, and spill cleanup. The document is designed to be read on an as-needed basis; that is, each chapter can stand alone or may be read in combination with others to help the reader determine the regulations relevant to his or her individual situation and needs. Every attempt has been made to include the requirements of other statutes and regulations that apply to PCB materials and provide references for the reader to consult for additional information.

  8. EMISSIONS OF POLYCHLORINATED BIPHENYLS AS PRODUCTS OF INCOMPLETE COMBUSTION FROM INCINERATORS

    EPA Science Inventory

    The paper discusses emissions of polychlorinated biphenyls (PCBs) as products of incomplete combustion from incinerators. PCBs were used widely as industrial chemicals, particularly as additives in electrical transformer cooling oil. Growing evidence of PCBs' role as a persistent...

  9. 78 FR 20640 - Polychlorinated Biphenyls (PCBs); Recycling Plastics from Shredder Residue

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-05

    ... AGENCY Polychlorinated Biphenyls (PCBs); Recycling Plastics from Shredder Residue AGENCY: Environmental... will generally allow for the recycling of plastic separated from shredder residue under the conditions described in the Voluntary Procedures for Recycling Plastics from Shredder Residue, relying principally on...

  10. EMISSIONS OF POLYCHLORINATED BIPHENYLS AS PRODUCTS OF INCOMPLETE COMBUSTION FROM INCINERATORS

    EPA Science Inventory

    The paper discusses emissions of polychlorinated biphenyls (PCBs) as products of incomplete combustion from incinerators. PCBs were used widely as industrial chemicals, particularly as additives in electrical transformer cooling oil. Growing evidence of PCBs' role as a persistent...

  11. Dual chirality control of palladium(II) complexes bearing tropos biphenyl diamine ligands.

    PubMed

    Aikawa, Kohsuke; Mikami, Koichi

    2005-12-14

    Axial and center chirality of Pd complexes with tropos biphenyl secondary diamine ligands is shown to be controlled by chiral amide (R)-DABNTf, which can efficiently discriminate between two enantiomeric Pd complexes.

  12. DECHLORINATION OF POLYCHLORINATED BIPHENYLS IN SEDIMENT SLURRIES BY PALLADIUM MODIFIED ZEROVALENT IRON

    EPA Science Inventory

    Polychlorinated biphenyls (PCBs) are one group of persistent organic pollutants (POPs) of international concern because of global distribution, persistence, and toxicity. Removal of these compounds from the environment presents a very tough challenge because they are highly hydro...

  13. COMPARING POLYCHLORINATED BIPHENYLS IN FARM-RAISED AND WILD-CAUGHT CATFISH FROM SOUTHERN MISSISSIPPI

    EPA Science Inventory

    Polychlorinated biphenyls (PCBs) are among the most thermally stable organic chemicals known. This characteristic has historically made them useful in a wide array of applications including use in electrical transformers and capacitors, varnishes, waxes, synthetic resins, epoxy ...

  14. COMPARING POLYCHLORINATED BIPHENYLS IN FARM-RAISED AND WILD-CAUGHT CATFISH FROM SOUTHERN MISSISSIPPI

    EPA Science Inventory

    Polychlorinated biphenyls (PCBs) are among the most thermally stable organic chemicals known. This characteristic has historically made them useful in a wide array of applications including use in electrical transformers and capacitors, varnishes, waxes, synthetic resins, epoxy ...

  15. ENANTIOMERIC COMPOSITION OF CHIRAL POLYCHLORINATED BIPHENYL ATROPISOMERS IN AQUATIC AND RIPARIAN BIOTA

    EPA Science Inventory

    The enantiomeric composition of polychlorinated biphenyl (PCB) atropisomers was measured in river and riparian biota (fish, bivalves, crayfish, water snakes, barn swallows) from selected sites throughout the United States by using chiral gas chromatography/mass spectrometry. Nonr...

  16. DECHLORINATION OF POLYCHLORINATED BIPHENYLS IN SEDIMENT SLURRIES BY PALLADIUM MODIFIED ZEROVALENT IRON

    EPA Science Inventory

    Polychlorinated biphenyls (PCBs) are one group of persistent organic pollutants (POPs) of international concern because of global distribution, persistence, and toxicity. Removal of these compounds from the environment presents a very tough challenge because they are highly hydro...

  17. ONTOGENETIC ALTERATIONS IN MOLECULAR AND STRUCTURAL CORRELATES OF DENDRITIC GROWTH FOLLOWING DEVELOPMENTAL EXPOSURE TO POLYCHLORINATED BIPHENYLS.

    EPA Science Inventory

    This is the first report showing both molecular and structural changes in brain following developmental exposure to a neurotoxicant. It is known that perinatal exposure to a neurotoxicant, polychlorinated biphenyls (PCBs), is associated with decreased IQ scores, impaired learnin...

  18. ONTOGENETIC ALTERATIONS IN MOLECULAR AND STRUCTURAL CORRELATES OF DENDRITIC GROWTH FOLLOWING DEVELOPMENTAL EXPOSURE TO POLYCHLORINATED BIPHENYLS.

    EPA Science Inventory

    This is the first report showing both molecular and structural changes in brain following developmental exposure to a neurotoxicant. It is known that perinatal exposure to a neurotoxicant, polychlorinated biphenyls (PCBs), is associated with decreased IQ scores, impaired learnin...

  19. Notifications Dated October 2, 2014 Submitted by We Energies to Dispose of Polychlorinated Biphenyl Remediation Waste

    EPA Pesticide Factsheets

    Disposal Notifications Dated October 2, 2014 for We Energies and the Utility Solid Waste Group Members’ Risk-Based Approvals to Dispose of Polychlorinated Biphenyl Remediation Waste at the Waste Management Disposal Sites in Menomonee Falls and Franklin, WI

  20. 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

  1. ENANTIOMERIC COMPOSITION OF CHIRAL POLYCHLORINATED BIPHENYL ATROPISOMERS IN AQUATIC AND RIPARIAN BIOTA

    EPA Science Inventory

    The enantiomeric composition of polychlorinated biphenyl (PCB) atropisomers was measured in river and riparian biota (fish, bivalves, crayfish, water snakes, barn swallows) from selected sites throughout the United States by using chiral gas chromatography/mass spectrometry. Nonr...

  2. Polychlorinated Biphenyls, Organochlorines & PD Risk: A Case Control Study in Alaska

    DTIC Science & Technology

    2009-05-01

    Organochlorines & PD Risk: A Case Control Study in Alaska 5b. GRANT NUMBER W81XWH-04-1-0490 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT...biphenyl (PCBs) residues, organochlorine pesticides and methylmercury with PD. The hypothesis is that increased exposure to these compounds will be...Parkinson’s disease, polychlorinated biphenyl, organochlorine pesticides, methylmercury, Alaska natives, neurodegeneration 16. SECURITY

  3. Preliminary results of the comparison of the electrochemical behavior of a thioether and biphenyl

    NASA Technical Reports Server (NTRS)

    Morales, W.; Jones, W. R.

    1983-01-01

    An electrochemical cell was constructed to explore the feasibility of using electrochemical techniques to simulate the tribochemistry of various substances. The electrochemical cell was used to study and compare the behavior of a thioether 1,3-bis(phenylthio) benzene and biphenyl. It is found that under controlled conditions biphenyl undergoes a reversible reduction to a radical anion whereas the thioether undergoes an irreversible reduction yielding several products. The results are discussed in relationship to boundary lubrication.

  4. Microcosm enrichment of biphenyl-degrading microbial communities from soils and sediments

    SciTech Connect

    Wagner-Doebler, I.; Bennasar, A.; Stroempl, C.; Bruemmer, I.; Eichner, C.; Grammel, I.; Moore, E.R.B.; Vancanneyt, M.

    1998-08-01

    A microcosm enrichment approach was employed to isolate bacteria which are representative of long-term biphenyl-adapted microbial communities. Growth of microorganisms was stimulated by incubating soil and sediment samples from polluted and nonpolluted sites with biphenyl crystals. After 6 months, stable population densities between 8 {times} 10{sup 9} and 2 {times} 10{sup 11} CFU/ml were established in the microcosms, and a large percentage of the organisms were able to grow on biphenyl-containing minimal medium plates. A total of 177 biphenyl-degrading strains were subsequently isolated and characterized by their ability to grow on biphenyl in liquid culture and to accumulate a yellow meta cleavage product when they were sprayed with dihydroxy-biphenyl. Isolates were identified by using a polyphasic approach, including fatty acid methyl ester (FAME) analysis, 16S rRNA gene sequence comparison, sodium dodecyl sulfate-polyacrylamide gel electrophoresis of whole-cell proteins, and genomic fingerprinting based on sequence variability in the 16S-23S ribosomal DNA intergenic spacer region. In all of the microcosms, isolates identified as Rhodococcus opacus dominated the cultivable microbial community, comprising a cluster of 137 isolates with very similar FAME profiles (Euclidean distances, <10) and identical 16S rRNA gene sequences.

  5. Investigation of saponification for determination of polychlorinated biphenyls in marine sediments.

    PubMed

    Numata, Masahiko; Yarita, Takashi; Aoyagi, Yoshie; Yamazaki, Misako; Takatsu, Akiko

    2005-02-01

    The effects of saponification conditions (temperature and water content of saponifying solution) on the determination of chlorinated biphenyls (CBs) in marine sediments were investigated. Although highly chlorinated biphenyls (nona- to deca-CBs) decomposed during high-temperature saponification, the degree of degradation was reduced by adding water to the ethanolic potassium hydroxide saponifying solution. Room-temperature saponification yielded quantitative recovery of highly chlorinated biphenyl surrogates but low extraction efficiencies of lightly chlorinated biphenyls (mono- to di-CBs). The same samples were analyzed by other extraction techniques, for example, pressurized liquid extraction, and analytical results were compared. The mono- and di-CB concentrations were correlated with the extraction temperatures of various extraction techniques. In particular, the concentrations of some CB congeners (CB11, CB14) were higher with saponification. The low degree of degradation of highly chlorinated biphenyls and the high recovery of lightly chlorinated biphenyls were compatible when room-temperature and high-temperature saponification were combined. Except for the anomalies of CB11 and CB14, the combined method gave satisfactory results for analysis of PCBs.

  6. Optimization of the Finnigan MAT 5100 Capillary Gas Chromatograph-Mass Spectrometer for the Analysis of Polychlorinated Biphenyls.

    DTIC Science & Technology

    1986-11-01

    FINNIGAN MAT 5100 CAPILLARY GAS CHROMATOGRAPH-MASS SPECTROMETER FOR THE ANALYSIS OF POLYCHLORINATED BIPHENYLS J.A. Hiltz - J. Power ,¢., DJ : .,:.JAN 1 4...CAPILLARY GAS CHROMATOGRAPH-MASS SPECTROMETER FOR THE ANALYSIS OF POLYCHLORINATED BIPHENYLS J.A. Hiltz - J.J. Power November 1986 Approved by B.F. Peters A...INTRODUCTION The use of polychlorinated biphenyls (PCBs) as dielectric fluids in electrical transformers and capacitors has been commomplace over the

  7. Brominated Biphenyls Prime Extensive Microbial Reductive Dehalogenation of Aroclor 1260 in Housatonic River Sediment

    PubMed Central

    Bedard, Donna L.; Van Dort, Heidi; Deweerd, Kim A.

    1998-01-01

    The upper Housatonic River and Woods Pond (Lenox, Mass.), a shallow impoundment on the river, are contaminated with polychlorinated biphenyls (PCBs), the residue of partially dechlorinated Aroclor 1260. Certain PCB congeners have the ability to activate or “prime” anaerobic microorganisms in Woods Pond sediment to reductively dehalogenate the Aroclor 1260 residue. We proposed that brominated biphenyls might have the same effect and tested the priming activities of 14 mono-, di-, and tribrominated biphenyls (350 μM) in anaerobic microcosms of sediment from Woods Pond. All of the brominated biphenyls were completely dehalogenated to biphenyl, and 13 of them primed PCB dechlorination. Measured in terms of chlorine removal and decrease in the proportion of hexa- through nonachlorobiphenyls, the microbial PCB dechlorination primed by several brominated biphenyls was nearly twice as effective as that primed by chlorinated biphenyls. Congeners containing a meta bromine primed Dechlorination Process N (flanked meta dechlorination), and congeners containing an unflanked para bromine primed Dechlorination Process P (flanked para dechlorination). Two ortho-substituted congeners, 2-bromobiphenyl and 2,6-dibromobiphenyl (2-BB and 26-BB), also primed Process N dechlorination. The most effective primers were 26-BB, 245-BB, 25-3-BB, and 25-4-BB. The microbial dechlorination primed by 26-BB converted ∼75% of the hexa- through nonachlorobiphenyls to tri- and tetrachlorobiphenyls in 100 days and removed ∼75% of the PCBs that are most persistent in humans. These results represent a major step toward identifying an effective method for accelerating PCB dechlorination in situ. The challenge now is to identify naturally occurring compounds that are safe and effective primers. PMID:9572952

  8. Polychlorinated biphenyls (PCBs) in bottom sediments: identification of sources.

    PubMed

    Wolska, Lidia; Mechlińska, Agata; Rogowska, Justyna; Namieśnik, Jacek

    2014-09-01

    Polychlorinated biphenyls (PCBs) can enter the environment from various sources. They are synthetic chemicals and as such are present in the environment mainly as mixtures containing various amounts of PCB congeners. It is therefore difficult to pinpoint the source of PCB emissions into the environment and the pathways along which they migrate there. The situation is different where locating the emission sources of polycyclic aromatic hydrocarbons (PAHs) is concerned. There is much information in the literature on the molecular markers that can be used to identify the sources of PAH emissions into the environment. Environmental samples like soil or bottom sediments are usually analysed for their contents of both groups of compounds. Therefore, with data on the origins of PAHs to hand, and seeking and comparing mutual correlations, one can attempt to define the probable sources of emission of PCBs. The purpose of this work was to identify the probable PCBs emission sources in bottom sediments using available data, that is polycyclic aromatic hydrocarbon diagnostic ratios. The numerical ratios of pairs of compounds such as fluoranthene/pyrene, phenanthrene/anthracene, fluoranthene/(fluoranthene+pyrene) and chrysene/benzo[a]anthracene are generally used as a tool for identifying and assessing pollution emission sources.

  9. Atmospheric emission of polychlorinated biphenyls from multiple industrial thermal processes.

    PubMed

    Liu, Guorui; Zheng, Minghui; Cai, Mingwei; Nie, Zhiqiang; Zhang, Bing; Liu, Wenbin; Du, Bing; Dong, Shujun; Hu, Jicheng; Xiao, Ke

    2013-03-01

    In this study, field measurements were conducted to estimate and characterize the atmospheric emission levels and profiles of polychlorinated biphenyls (PCBs) from multiple industrial thermal processes. The emission levels and profiles of PCBs from five types of thermal processes at twenty-three plants were studied and compared with eight processes reported in our previous studies. Correlation analysis was preformed to identify a marker congener for emission of ΣPCB. A significant correlation was observed between congener CB-118 and ΣPCB (R(2)=0.65 and p<0.01), which suggests that CB-118 is a good marker congener for emission of ΣPCB. The profiles of PCBs emitted from the thirteen thermal processes were compared, and this information could be used for studying source-receptor relationships and identifying the specific sources of PCBs. To prioritize the sources for control, the concentrations of PCBs from thirteen industrial thermal sources were compared. The PCB concentrations from secondary zinc smelting and thermal wire reclamation were about one to three order magnitude higher than those of other sources, which suggests that these two sources be given priority in PCB source control. Finally, the atmospheric emission factors of PCBs from the thirteen industrial sources were summarized, and these data will be useful for developing an integrated emission inventory of PCBs.

  10. An Efficient Approach to Sulfate Metabolites of Polychlorinated Biphenyls

    PubMed Central

    Li, Xueshu; Parkin, Sean; Duffel, Michael W.; Robertson, Larry W.; Lehmler, Hans-Joachim

    2009-01-01

    Polychlorinated biphenyls (PCBs), a major class of persistent organic pollutants, are metabolized to hydroxylated PCBs. Several hydroxylated PCBs are substrates of cytosolic phase II enzymes, such as phenol and hydroxysteroid (alcohol) sulfotransferases; however, the corresponding sulfation products have not been isolated and characterized. Here we describe a straightforward synthesis of a series of ten PCB sulfate monoesters from the corresponding hydroxylated PCBs. The hydroxylated PCBs were synthesized by coupling chlorinated benzene boronic acids with appropriate brominated (chloro-)anisoles, followed by demethylation with boron tribromide. The hydroxylated PCBs were sulfated with 2,2,2-trichloroethyl chlorosulfate using DMAP as base. Deprotection with zinc powder/ammonium formate yielded the ammonium salts of the desired PCB sulfate monoesters in good yields when the sulfated phenyl ring contained no or one chlorine substituent. However, no PCB sulfate monoesters were isolated when two chlorines were present ortho to the sulfated hydroxyl group. To aid with future quantitative structure activity relationship studies, the structures of two 2,2,2-trichloroethyl-protected PCB sulfates were verified by X-ray diffraction. PMID:19345419

  11. Hydroxylated Polychlorinated Biphenyls in the Environment: Sources, Fate, and Toxicities

    PubMed Central

    Tehrani, Rouzbeh; Van Aken, Benoit

    2013-01-01

    Hydroxylated polychlorinated biphenyls (OH-PCBs) are produced in the environment by the oxidation of PCBs through a variety of mechanisms, including metabolic transformation in living organisms and abiotic reactions with hydroxyl radicals. As a consequence, OH-PCBs have been detected in a wide range of environmental samples, including animal tissues, water, and sediments. OH-PCBs have recently raised serious environmental concerns because they exert a variety of toxic effects at lower doses than the parent PCBs and they are disruptors of the endocrine system. Although evidence has accumulated about the widespread dispersion of OH-PCBs in various compartments of the ecosystem, little is currently known about their biodegradation and behavior in the environment. OH-PCBs are today increasingly considered as a new class of environmental contaminants that possess specific chemical, physical, and biological properties not shared with the parent PCBs. This article reviews recent findings regarding the sources, fate, and toxicities of OH-PCBs in the environment. PMID:23636595

  12. Reproduction success of American kestrels exposed to dietary polychlorinated biphenyls.

    PubMed

    Fernie, K J; Smits, J E; Bortolotti, G R; Bird, D M

    2001-04-01

    While reproduction of wild birds is adversely affected by multiple environmental contaminants, we determined that polychlorinated biphenyls (PCBs) alone alter reproduction. Captive American kestrels (Falco sparverius), fed PCB-spiked (Aroclor 1248:1254:1260) food (7 mg/kg body weight/d) prior to and during the first breeding season only (100 d) laid eggs with environmentally relevant levels of total PCBs (34.0 microg/g whole egg wet wt vs 0 microg/g for controls). Reproduction changed during, not after, PCB exposure in this two-year study. The PCB-exposed pairs laid smaller clutches later in the season and laid more totally infertile clutches. Hatching success was reduced in PCB-exposed pairs, and 50% of PCB nestlings died within 3 d of hatching. Nearly 60% of PCB-exposed pairs with hatchlings failed to produce fledglings. Higher levels of total PCB residues and congeners were associated with later clutch initiation and fewer fertile eggs, hatchlings, and fledglings. We suggest that nonpersistent PCB congeners have a greater influence on reproduction than do persistent congeners.

  13. Preconception maternal polychlorinated biphenyl concentrations and the secondary sex ratio

    SciTech Connect

    Taylor, Kira C.; Jackson, Leila W.; Lynch, Courtney D.; Kostyniak, Paul J.; Buck Louis, Germaine M. . E-mail: louisg@mail.nih.gov

    2007-01-15

    The secondary sex ratio is the ratio of male to female live births and historically has ranged from 102 to 106 males to 100 females. Temporal declines have been reported in many countries prompting authors to hypothesize an environmental etiology. Blood specimens were obtained from 99 women aged 24-34 prior to attempting pregnancy and quantified for 76 polychlorinated biphenyl (PCB) congeners using dual column gas chromatography with electron capture detection. Women were prospectively followed until pregnancy or 12 cycles of trying. The odds of a male birth for three PCB groupings (total, estrogenic, anti-estrogenic) controlling for maternal characteristics were estimated using logistic regression. Among the 50 women with live births and PCB data, 26 female and 24 male infants were born (ratio 0.92). After adjusting for age and body mass index, odds of a male birth were elevated among women in the second (OR=1.29) and third (OR=1.48) tertiles of estrogenic PCBs; odds (OR=0.70) were reduced among women in the highest tertile of anti-estrogenic PCBs. All confidence intervals included one. The direction of the odds ratios in this preliminary study varied by PCB groupings, supporting the need to study specific PCB patterns when assessing environmental influences on the secondary sex ratio.

  14. Organochlorine pesticides and polychlorinated biphenyls in California sea lions.

    PubMed

    Kannan, K; Kajiwara, N; Le Boeuf, B J; Tanabe, S

    2004-10-01

    Concentrations of polychlorinated biphenyls (PCBs), DDTs, chlordanes, HCHs, hexachlorobenzene (HCB), dieldrin, heptachlor epoxide, tris(4-chlorophenyl)methane (TCPMe), and tris(4-chlorophenyl)methanol (TCPMOH) were measured in the blubber of California sea lions (Zalophus californianus) collected in 2000. DDTs were the most predominant contaminants, followed by PCBs, chlordanes, TCPMe, HCHs, TCPMOH, dieldrin, and heptachlor epoxide. Concentrations of PCBs and DDTs varied from a few microg/g to several hundreds of microg/g on a lipid weight basis. Concentrations of DDTs have declined by an order of magnitude over the last three decades in California sea lions; nevertheless, the measured concentrations of PCBs and DDTs in California sea lions are still some of the highest values reported for marine mammals in recent years. Concentrations of organochlorines were highly correlated with one another. Concentrations of PCBs and DDTs in the blubber of gray whale, humpback whale, northern elephant seal, and harbor seal, and in the adipose fat of sea otter, were lower than the levels found in California sea lions, and were in the range of a few to several microg/g on a lipid weight basis.

  15. Environmental determinants of polychlorinated biphenyl concentrations in residential carpet dust

    PubMed Central

    DellaValle, Curt T.; Wheeler, David C.; Deziel, Nicole C.; De Roos, Anneclaire J.; Cerhan, James R.; Cozen, Wendy; Severson, Richard K.; Flory, Abigail R.; Locke, Sarah J.; Colt, Joanne S.; Hartge, Patricia; Ward, Mary H.

    2014-01-01

    Polychlorinated biphenyls (PCBs), banned in the United Sates in the late 1970s, are still found in indoor and outdoor environments. Little is known about the determinants of PCB levels in homes. We measured concentrations of 5 PCB congeners (105, 138, 153, 170, 180) in carpet dust collected between 1998–2000 from 1,187 homes in four sites: Detroit, Iowa, Los Angeles, and Seattle. Home characteristics, occupational history, and demographic information were obtained by interview. We used a geographic information system to geocode addresses and determine distances to the nearest major road, freight route, and railroad, percentage of developed land, number of industrial facilities within 2 km of residences, and population density. Ordinal logistic regression was used to estimate the associations between the covariates of interest and the odds of PCB detection in each site separately. Total PCBs levels (all congeners < maximum practical quantitation limit [MPQL] vs. at least one congener ≥ MPQL to < median concentration vs. at least one congener >median concentration) were positively associated with either percentage of developed land (ORrange: 1.01-1.04 for each percentage increase) or population density (OR: 1.08 for every 1,000/mi2) in each site. The number of industrial facilities within 2 km of a home was associated with PCB concentrations; however, facility type and the direction of the association varied by site. Our findings suggest that outdoor sources of PCBs may be significant determinants of indoor concentrations. PMID:23952055

  16. Pinpointing Biphenyl Dioxygenase Residues That Are Crucial for Substrate Interaction

    PubMed Central

    Zielinski, Marco; Kahl, Silke; Hecht, Hans-Jürgen; Hofer, Bernd

    2003-01-01

    Three regions of the biphenyl dioxygenase (BDO) of Burkholderia sp. strain LB400 have previously been shown to significantly influence the interaction between enzyme and substrates at the active site. For a further discrimination within these regions, we investigated the effects of 23 individual amino acid exchanges. The regiospecificity of substrate dioxygenation was used as a sensitive means to monitor changes in the steric-electronic structure of the active site. Replacements of residues that, according to a model of the BDO three-dimensional structure, directly interact with substrates in most, but not all, cases (Met231, Phe378, and Phe384) very strongly altered this parameter (by factors of >7). On the other hand, a number of amino acids (Ile243, Ile326, Phe332, Pro334, and Trp392) which have no contacts with substrates also strongly changed the site preference of dioxygenation (by factors of between 2.6 and 3.5). This demonstrates that residues which had not been predicted to be influential can play a pivotal role in BDO specificity. PMID:14617661

  17. Phytoremediation of soil contaminated with cadmium, copper and polychlorinated biphenyls.

    PubMed

    Wu, Longhua; Li, Zhu; Han, Cunliang; Liu, Ling; Teng, Ying; Sun, Xianghui; Pan, Cheng; Huang, Yujuan; Luo, Yongming; Christie, Peter

    2012-07-01

    A pot experiment and afield trial were conducted to study the remediation of an aged field soil contaminated with cadmium, copper and polychlorinated biphenyls (PCBs) (7.67 +/- 0.51 mg kg(-1) Cd, 369 +/- 1 mg kg(-1) Cu in pot experiment; 8.46 +/- 0.31 mg kg(-1) Cd, 468 +/- 7 mg kg(-1) Cu, 323 +/- 12 microg kg(-1) PCBs for field experiment) under different cropping patterns. In the pot experiment Sedum plumbizincicola showed pronounced Cd phytoextraction. After two periods (14 months) of cropping the Cd removal rates in these two treatments were 52.2 +/- 12.0 and 56.1 +/- 9.1%, respectively. Total soil PCBs in unplanted control pots decreased from 323 +/- 11 to 49.3 +/- 6.6 microg kg(-1), but with no significant difference between treatments. The field microcosm experiment intercropping of three plant species reduced the yield of S. plumbizincicola, with a consequent decrease in soil Cd removal. S. plumbizincicola intercropped with E. splendens had the highest shoot Cd uptake (18.5 +/- 1.8 mg pot(-1)) after 6 months planting followed by intercropping with M. sativa (15.9 +/- 1.9 mg pot(-1)). Liming with S. plumbizincicola intercropped with M. sativa significantly promoted soil PCB degradation by 25.2%. Thus, adjustment of soil pH to 5.56 combined with intercropping with S. plumbizincicola and M. sativagave high removal rates of Cd, Cu, and PCBs.

  18. Polychlorinated Biphenyls Water Pollution along the River Nile, Egypt

    PubMed Central

    Megahed, Ayman Mohamed; Dahshan, Hesham; Abd-El-Kader, Mahdy A.; Abd-Elall, Amr Mohamed Mohamed; Elbana, Mariam Hassan; Nabawy, Ehab; Mahmoud, Hend A.

    2015-01-01

    Ten polychlorinated biphenyl (PCB) congeners were determined in water samples collected along the River Nile using gas chromatography-electron capture detector (GC-ECD). PCB concentrations ranged from 14 to 20 μg/L, which were higher than those reported in previous studies, indicating serious PCB pollution in the River Nile. PCB congener profiles varied depending on the sampling sties. PCB-138 was the predominant congener accounting for more than 18% of total PCBs. The composition of PCB congeners in the water revealed that highly chlorinated PCB technical mixtures such as Aroclor 1254 was the main PCB production historically used in Egypt. An increasing trend in PCB levels from the upper stream to the Nile estuaries was observed. The calculated flux of PCBs indicated that 6.8 tons of PCBs is dumped into the Mediterranean Sea each year from the River Nile. The hazard quotients and carcinogenic risk caused by PCB pollution in the River Nile were above the acceptable level indicating that PCBs in the River Nile water pose adverse health effects for all age groups. Our findings revealed that PCBs possess a serious risk to the Egyptian population that depends mainly on the River Nile as a source of water. Thus, stricter legislation and regulatory controls should be applied to reduce the risk of PCBs in Egypt. PMID:26798844

  19. Polychlorinated Biphenyls Water Pollution along the River Nile, Egypt.

    PubMed

    Megahed, Ayman Mohamed; Dahshan, Hesham; Abd-El-Kader, Mahdy A; Abd-Elall, Amr Mohamed Mohamed; Elbana, Mariam Hassan; Nabawy, Ehab; Mahmoud, Hend A

    2015-01-01

    Ten polychlorinated biphenyl (PCB) congeners were determined in water samples collected along the River Nile using gas chromatography-electron capture detector (GC-ECD). PCB concentrations ranged from 14 to 20 μg/L, which were higher than those reported in previous studies, indicating serious PCB pollution in the River Nile. PCB congener profiles varied depending on the sampling sties. PCB-138 was the predominant congener accounting for more than 18% of total PCBs. The composition of PCB congeners in the water revealed that highly chlorinated PCB technical mixtures such as Aroclor 1254 was the main PCB production historically used in Egypt. An increasing trend in PCB levels from the upper stream to the Nile estuaries was observed. The calculated flux of PCBs indicated that 6.8 tons of PCBs is dumped into the Mediterranean Sea each year from the River Nile. The hazard quotients and carcinogenic risk caused by PCB pollution in the River Nile were above the acceptable level indicating that PCBs in the River Nile water pose adverse health effects for all age groups. Our findings revealed that PCBs possess a serious risk to the Egyptian population that depends mainly on the River Nile as a source of water. Thus, stricter legislation and regulatory controls should be applied to reduce the risk of PCBs in Egypt.

  20. The inducing properties of polychlorinated biphenyls on hepatic monooxygenases.

    PubMed

    Alvares, A P; Kappas, A

    1977-11-01

    The polychlorinated biphenyls (PCBs) represent a newly recognized and widely distributed category of environmental pollutants whose biologic impact on animals and man may be both substantial and highly detrimental. The pharmacologic effects of these agents on enzymes in the liver which metabolize drugs and other foreign compounds, such as carcinogens, are powerful and long lasting. PCBs mimic the effects produced on these enzymes by drugs, such as phenobarbital, and carcinogens, such as 3-methylcholanthrene. They are potent inducers of cytochromes P-45O and P-448 and associated enzymic activities. Further, these chemicals can cross the placental barrier and be transmitted through maternal milk to the newborn infant causing marked increases in drug biotransformation enzymes in the fetus and the neonate. Studies with the use of microscope immersion oils containing PCBs show that application of minute amounts of these oils to the skin of experimental animals results in a marked induction of the drug-and carcinogen-metabolizing enzymes. These findings suggest that even trivial skin exposure to chemicals, such as PCBs, can have significant and perhaps harmful biologic effects in man.

  1. Chiral Polychlorinated Biphenyl Transport, Metabolism and Distribution - A Review

    PubMed Central

    Lehmler, Hans-Joachim; Harrad, Stuart J.; Hühnerfuss, Heinrich; Kania-Korwel, Izabela; Lee, Cindy M.; Lu, Zhe; Wong, Charles S.

    2009-01-01

    Chirality can be exploited to gain insight into enantioselective fate processes that may otherwise remain undetected because only biological, but not physical and chemical transport and transformation processes in an achiral environment will change enantiomer compositions. This review provides an in-depth overview of the application of chirality to the study of chiral polychlorinated biphenyls (PCBs), an important group of legacy pollutants. Like other chiral compounds, individual PCB enantiomers may interact enantioselectively (or enantiospecifically) with chiral macromolecules, such as cytochrome P-450 enzymes or ryanodine receptors, leading to differences in their toxicological effects and the enantioselective formation of chiral biotransformation products. Species and congener-specific enantiomer enrichment has been demonstrated in environmental compartments, wildlife and mammals, including humans, typically due to a complex combination of biotransformation processes and uptake via the diet by passive diffusion. Changes in the enantiomer composition of chiral PCBs in the environment have been used to understand complex aerobic and anaerobic microbial transformation pathways, to delineate and quantify PCB sources and transport in the environment, to gain insight into the biotransformation of PCBs in aquatic food webs, and to investigate the enantioselective disposition of PCBs and their methylsulfonyl PCBs metabolites in rodents. Overall, changes in chiral signatures are powerful, but currently underutilized tools for studies of environmental and biological processes of PCBs. PMID:20384371

  2. Source apportionment of polychlorinated biphenyls in the tidal Delaware River.

    PubMed

    Du, Songyan; Belton, Thomas J; Rodenburg, Lisa A

    2008-06-01

    The Delaware River, similar to many surface water bodies throughout the United States, is impaired due to polychlorinated biphenyl (PCB) concentrations that exceed the federal water quality standard. A total maximum daily load (TMDL) for PCBs in the Delaware was promulgated in 2003 after construction of a detailed water quality model that relied upon estimated PCB loadings from sources such as wastewater treatment plant effluents, contaminated sites, and tributaries. The purpose of this project was to corroborate this loading estimate by analyzing ambient water column data on PCB concentrations in the Delaware River via positive matrix factorization (PMF) in order to identify covarying congener patterns that are, in theory, associated with sources. The PMF program identified six factors (covarying congener patterns) that appear to be associated with sources, such as sediment resuspension, contaminated sites, and wastewater effluents and combined sewer overflows (CSOs). PCB 11 was found to be a useful tracer for CSO/ wastewater inputs despite the fact that no known dye manufacturers exist in the watershed. This analysis generally corroborates the PCB loading estimate used in the water quality model.

  3. Electrode materials for biphenyl-based rectification devices.

    PubMed

    Parashar, Sweta; Srivastava, Pankaj; Pattanaik, Manisha

    2013-10-01

    An ab initio approach was utilized to explore the electronic transport properties of 4'-thiolate-biphenyl-4-dithiocarboxylate (TBDT) sandwiched between two electrodes made of various materials X (X = Cu, Ag, and Au). Analysis of current-voltage (I-V) characteristics, rectification performance, transmission functions, and the projected density of states (PDOS) under various external voltage biases showed that the transport properties of these constructed systems are markedly impacted by the choice of electrode materials. Further, Cu electrodes yield the best rectifying behavior, followed by Ag and then Au electrodes. Interestingly, the rectification effects can be tuned by changing the torsion angle between the two phenyl rings, as well as by stretching the contact distances between the end group and the electrodes. For Cu, the maximum rectifying ratio increases by 37 % as the contact distance changes from 1.7 Å to 1.9 Å. This is due to an increase in coupling strength asymmetry between the molecule and the electrodes. Our findings are compared with the results reported for other systems. The present calculations are helpful not only for predicting the optimal electrode material for practical applications but also for achieving better control over rectifying performance in molecular devices.

  4. Polychlorinated biphenyls and their interaction with the environment

    SciTech Connect

    Dickerson, K.S.; Korte, N.E.

    1994-05-01

    This document is a review of the existing technical literature regarding the physical and biological properties of polychlorinated biphenyls (PCBs) and their interaction with the environment. It is intended to be used when evaluating PCB-contaminated soil and the effects of specific environmental conditions on PCB degradation. PCBs are a class of chlorinated aromatic compounds with 209 possible structural arrangements. The composition of PCBs in the environment changes over time due to various physiochemical and biological properties and processes: vapor pressure, solubility, octanol-water partitioning, adsorption, and biodegradation. As the number of chlorine atoms increases, both vapor pressure and water solubility decrease, while adsorption and the octanol-water partitioning coefficient increase. Dechlorination of PCBs occurs primarily through aerobic and anaerobic microbial degradation. Aerobic bacteria preferentially dechlorinate less-chlorinated PCBs, while anaerobic bacteria preferentially dechlorinate more highly chlorinated PCBs. The less-chlorinated PCB congeners are less persistent in the environment due to volatilization, solubility, and aerobic biodegradation, while the more-chlorinated PCBs are more persistent in the environment due to adsorption. The composition of an original PCB mixture in the environment can be expected to change due to a combination of processes described above. Any attempt to determine the source of PCBs or Aroclors identified in an environment sample must be approached with caution to avoid inaccurate conclusions.

  5. Polychlorinated Biphenyls Disrupt Hepatic Epidermal Growth Factor Receptor Signaling.

    PubMed

    Hardesty, Josiah E; Wahlang, Banrida; Falkner, K Cameron; Clair, Heather B; Clark, Barbara J; Ceresa, Brian P; Prough, Russell A; Cave, Matthew C

    2016-07-26

    1. Polychlorinated biphenyls (PCBs) are persistent environmental pollutants that disrupt hepatic xenobiotic and intermediary metabolism, leading to metabolic syndrome and nonalcoholic steatohepatitis (NASH). 2. Since phenobarbital indirectly activates Constitutive Androstane Receptor (CAR) by antagonizing growth factor binding to the epidermal growth factor receptor (EGFR), we hypothesised that PCBs may also diminish EGFR signaling. 3. The effects of the PCB mixture Aroclor 1260 on the protein phosphorylation cascade triggered by EGFR activation were determined in murine (in vitro and in vivo) and human models (in vitro). EGFR tyrosine residue phosphorylation was decreased by PCBs in all models tested. 4. The IC50 values for Aroclor 1260 concentrations that decreased Y1173 phosphorylation of EGFR were similar in murine AML-12 and human HepG2 cells (∼2-4 μg/mL). Both dioxin and non-dioxin-like PCB congeners decreased EGFR phosphorylation in cell culture. 5. PCB treatment reduced phosphorylation of downstream EGFR effectors including Akt and mTOR, as well as other phosphoprotein targets including STAT3 and c-RAF in vivo. 6. PCBs diminish EGFR signaling in human and murine hepatocyte models and may dysregulate critical phosphoprotein regulators of energy metabolism and nutrition, providing a new mechanism of action in environmental diseases.

  6. Characterisation of Polychlorinated Biphenyls in Coastal Inland Seawater, Nigeria

    NASA Astrophysics Data System (ADS)

    Benson, Nsikak U.; Fred-Ahmadu, Omowunmi H.; Adedapo, Adebusayo E.; Anake, Winifred U.

    2017-05-01

    The concentrations of polychlorinated biphenyls (PCBs) were determined in samples of surface seawater collected from five (5) different locations along the coastline of a tropical lagoon. The surface water samples were analysed using gas chromatography coupled with electron capture detector (GC-ECD) with fifteen (15) PCB congeners detected across the studied area. The chlorobiphenyls levels are in the order Ebute Ero > Oko Baba > Ijora > Lagos Island > Unilag lagoon front with levels 107.89, 53.15, 34.90, 27.78, and 2.15 mg/L, respectively. The enhanced average concentration of PCBs at the Ebute Ero site is due to the predominance of PCB-180 and PCB-185. A negative correlation was found between the total PCB concentration and the level of dissolved oxygen. Although, the results indicated fairly high levels of PCBs, the anthropogenic contributions from industrial releases and domestic activities may be largely associated with the detected concentrations of the di-, tetra-, penta-, hexa-, hepta-, and octa-chlorobiphenyls.

  7. Reliability of the determinations of polychlorinated contaminants (biphenyls, dioxins, furans)

    SciTech Connect

    Horwitz, W.; Albert, R.

    1996-05-01

    Precision performance parameters from results of 34 interlaboratory performance studies of polychlorinated aromatic ring compounds (biphenyls, dioxins, and furans) (PCCs) have been recalculated by using the Internation Union of Pure and Applied Chemistry-1987 harmonized protocol. Most studies of 1052 test samples, 56 analytes, 19 matrixes, and 2 types of detectors (electron capture and mass spectrometers) provide among-laboratories relative standard deviations (RSD{sub R}s), that are considerably better than those predicted form the Horwitz equation at fractional concentrations of 10{sup {minus}6} down to 10{sup {minus}15}. The explanation suggested is that supplying common reference calibration solutions, as was done in many of these studies, does not reflect realistic operating conditions. Furthermore, the ability to repeat, discuss, and reassess aberrant reported values results in underestimating the true RSD{sub R}. The commonly reported problems of preparation of standard calibrating solutions, instability of the detections system, and failure to follow quality control instructions and good laboratory practices may be important sources of inter-laboratory variability in PCC determinations. 55 refs., 15 figs., 7 tabs.

  8. Levels of polychlorinated biphenyls (PCBs) in transformer oils from Korea.

    PubMed

    Shin, Sun Kyoung; Kim, Tae Seung

    2006-10-11

    Using Korean waste official method, polychlorinated biphenyls (PCBs) were analyzed from 33 transformer oils collected under National Institute of Environmental Research (NIER) in Republic of Korea (ROK) and their emission rate in Korea was estimated. Practical quantification limits analyzed by this method were in the ranges of 0.02 and 0.05 mg L(-1), and recovery of samples was in the ranges of 77-97%. The analytical results showed that PCBs in the transformer oils were identified as Aroclor 1242, 1254 or 1260. Twenty-nine samples were determined to contain PCBs of >0.05 mg L(-1) and among these samples, nine samples contained to have >2 mg kg(-1) which is limit of Waste Control Act (WCA) with regard to PCBs in transformer oil from Korea. The concentrations of PCBs in transformer oils were between N.D. (not detected) and 48.33 mg kg(-1). PCBs concentrations did not exceed 50 mg kg(-1) which is generally accepted limit for the definition of waste in POPs Guideline of Basel Convention.

  9. Exposure to polychlorinated biphenyls (PCBs) among welders in Sri Lanka.

    PubMed

    Lankatilake, Kantha; Samaranayake, Dulani; Piyathunga, Kasun

    2012-01-01

    Polychlorinated biphenyls (PCBs) are a group of persistent organic pollutants with the ability to cause adverse impacts on human health and the environment. This study describes the indiscriminate use of PCB-contaminated transformer oil as a coolant in informal welding shops in Kalutara, Sri Lanka. Sixty-three welders, one each from a convenience sample of 63 welding workshops participated in the study. We administered a questionnaire and observed work practices. Sixty-two (98%) workplaces used transformer oil as the coolant in the welding equipment, 60 (95%) claiming that it was the only one available. Sixty-two (98%) did not use any protective measures when refilling coolant oil, while none of them safely disposed of the empty coolant oil containers. Only four (6%) were aware of the possible health effects of PCB-contaminated coolant oil. Health and safety measures in the work places studied were very poor. Coolant oil samples from a sub-sample of 30 welding workshops were tested for PCBs; 19 (63%) were positive. PCB-contaminated coolant oil is widely used by the welders in Kalutara without adequate precautions or safety measures.

  10. Continuous catalytic hydrodechlorination of polychlorinated biphenyls (PCBs) in transformer oil.

    PubMed

    Veriansyah, Bambang; Choi, Hye-Min; Lee, Youn-Woo; Kang, Jeong Won; Kim, Jae-Duck; Kim, Jaehoon

    2009-12-01

    Continuous catalytic hydrodechlorination of polychlorinated biphenyls (PCBs) in the presence of transformer oils was carried out in a fixed bed reactor using a 57.6 wt% Ni on silicon oxide-aluminum oxide (SiO(2)-Al(2)O(3)) catalyst. Reaction temperatures ranging 150-300 degrees C, PCBs concentrations ranging 50-200 ppm, and reaction times ranging 1-8 h were tested. At a higher reaction temperature or at a lower PCBs concentration, catalytic activity was higher and complete dechlorination of PCBs resulted even at long reaction time. Catalyst regeneration using hexane and 0.1 M sodium hydroxide (NaOH) was effective to restore the catalytic activity. Fresh, spent and regenerated catalysts were characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analysis. XRD analysis revealed growth of Ni crystallite size of the spent and the regenerated catalysts. XPS analysis showed that a considerable amount of chlorine and carbon species were deposited on the surface of the spent catalyst, which may play a role in the catalysts deactivation.

  11. Thyroid function in Yusho patients exposed to polychlorinated biphenyls (PCB)

    SciTech Connect

    Murai, K.; Okamura, K.; Tsuji, H.; Kajiwara, E.; Watanabe, H.; Akagi, K.; Fujishima, M.

    1987-12-01

    Thyroid function was investigated in 123 Yusho patients who were exposed to toxic levels of polychlorinated biphenyls (PCBs) 16 years ago. In Yusho patients, compared with the patients without evidence of Yusho or normal controls, the serum triiodothyronine (T/sub 3/) and thyroxine (T/sub 4/) levels were significantly higher, while thyroid stimulating hormone (TSH) levels measured by sensitive assay were normal. There was no difference in serum levels of albumin, alkaline phosphatase, total cholesterol, and thyroxine binding globulin (TBG) between the two groups and the prevalence of positive antithyroid autoantibodies was almost the same, suggesting that hyperthyroxinemia in Yusho patients was not due to increased TBG binding or abnormal autoimmune mechanism. Serum free T/sub 4/ levels, however, were not elevated, although T/sub 4//TBG ratio was significantly higher. The thyroid hormone levels were higher than normal value in 4 of 123 Yusho patients but only 1 case had clinical symptoms such as excessive perspiration. Despite higher serum PCBs in Yusho patients, there was no correlation between PCB levels and levels of T/sub 3/, T/sub 4/, or TSH. The present results suggest hyperthyroxinemia without obvious clinical symptoms in Yusho patients long after exposure to PCBs.

  12. Polychlorinated Biphenyl (PCB) carcinogenicity with special emphasis on airborne PCBs

    PubMed Central

    Robertson, Larry W.; Ludewig, Gabriele

    2011-01-01

    Polychlorinated biphenyls (PCBs) are industrial chemicals used in various applications requiring chemical stabilityand have now become widely dispersed. Their characteristics of persistence, low water/higher lipid solubility, contribute to their ability to bioconcentrate and bioaccumulate. Traditionally PCBs have been regulated as food contaminants and the general population is primarily exposed by that route. PCBs in foodstuffs are generally higher chlorinated, resistant to metabolic breakdown, and elicit toxic changes that are thought to be predominantly receptor/parent PCB-driven. But for certain occupational exposures, and for those persons residing or working in contaminated buildings, and in large cities, an inhalation route of exposure may predominate. Airborne PCBs are, in contrast to foodborne PCBs, lower chlorinated, more volatile, and subject to metabolic attack. In this review, we have explored (geno-) toxic manifestations of PCBs typical of those found in air. Here metabolic conversion of the parent PCB to hydroxylated and other metabolic progeny appear to play a dominant role, especially in genotoxicity. We should be cognizant of the impact of exposures to airborne PCBs for those individuals who are occupationally exposed, for persons living near contaminated sites, for those who work or go to school in contaminated buildings, and especially cognizant of the young, the socio-economically disadvantaged and medically-underserved or nutritionally-deficient populations. PMID:21686028

  13. Cytogenetic and teratogenic test of polybrominated biphenyls in rodents.

    PubMed

    Wertz, G F; Ficsor, G

    1978-04-01

    Previously we reported negative terata and c-mitosis synergism of FireMaster (polybrominated biphenyls) with colchicine in subacutely treated rats. Now we report absence of chromosome aberrations from FireMaster and absence of c-mitosis synergism of FireMaster and colchicine in male mice. For the study of chromosome aberrations groups of three mice received 0, 50, or 500 mg/kg FireMaster or 4.5 mg/kg triethylenemelamine (TEM) dissolved in dimethyl sulfoxide through a single stomach gavage administration. Five hours before killing the animals were injected with 5 mg colchicine/kg. Groups of 3 mice from each treatment killed 12, 24, and 48 hr after treatment. From the bone marrow of each of 36 mice 100 metaphases were scored for gaps, chromatid and chromosome breaks, rearrangements and pulverized chromosomes. Only TEM induced chromosome damage. For detection of synergism between FireMaster and colchicine, slides prepared for chromosome analysis were also scored for metaphase and mitotic indeces. Control mice for detection of synergism were treated as for the chromosome study but were not injected with colchicine. Approximately 1000 cells were scored from each of 72 animals for determination of metaphase and mitotic indeces. FireMaster did not show c-mitosis synergism with colchicine in mice. Treatment with FireMaster did not cause visually recognizable toxicity.

  14. Developmental abilities of children exposed to polybrominated biphenyls (PBB).

    PubMed Central

    Seagull, E A

    1983-01-01

    To investigate whether ingestion of polybrominated biphenyls has an adverse effect on the neuropsychological development of young children exposed in utero and in infancy, five tests of the McCarthy Scales of Children's Abilities were administered to a group of 19 PBB-exposed Michigan children. When the data for the exposed group were analyzed according to body burden of PBB as determined by fat biopsy, correlations ranging from -.5228 to -.3004 were found between the natural logarithms of the children's fat PBB values and their standardized scores on the developmental scales. Four of the five correlations were significant at p less than .05. Multivariate analysis of covariance confirmed the existence of a significant main effect for fat PBB level, with parental education held constant. Children with higher body burdens of PBB (greater than .100 ppm) scored significantly lower than exposed children with lower body burdens on the same four tests, and on a composite score representing overall performance. These results suggest the existence of an inverse relationship between body levels of PBB and some developmental abilities in young children. PMID:6297321

  15. Developmental abilities of children exposed to polybrominated biphenyls (PBB).

    PubMed

    Seagull, E A

    1983-03-01

    To investigate whether ingestion of polybrominated biphenyls has an adverse effect on the neuropsychological development of young children exposed in utero and in infancy, five tests of the McCarthy Scales of Children's Abilities were administered to a group of 19 PBB-exposed Michigan children. When the data for the exposed group were analyzed according to body burden of PBB as determined by fat biopsy, correlations ranging from -.5228 to -.3004 were found between the natural logarithms of the children's fat PBB values and their standardized scores on the developmental scales. Four of the five correlations were significant at p less than .05. Multivariate analysis of covariance confirmed the existence of a significant main effect for fat PBB level, with parental education held constant. Children with higher body burdens of PBB (greater than .100 ppm) scored significantly lower than exposed children with lower body burdens on the same four tests, and on a composite score representing overall performance. These results suggest the existence of an inverse relationship between body levels of PBB and some developmental abilities in young children.

  16. Neutrophhil function after exposure to polychlorinated biphenyls in vitro

    SciTech Connect

    Ganey, P.E.; Denison, M.; Roth, R.A.; Robinson, J.P. )

    1993-10-01

    Polychlorinated biphenyls (PCBs) are known to be immunotoxic, yet the effects on neutrophil (PMN) function are not well characterized. We incubated PMNs isolated from rat peritoneum with a mixture of PCB congeners, Aroclor 1242, in the absence or presence of either phorbol myristate acetate (PMA) to stimulate generation of supoxide anion (O[sub 2]) or N-formyl-methionyl-leucyl-phenylalanine (fMLP) to induce degranulation (measured as release of [beta]-glucuronidase). Aroclor 1242 alone stimulated O[sub 2] production at a concentration of 10 [mu]g/ml. Significant cytotoxicity was not observed under these conditions. This concentration of Aroclor 1242 also increased O[sub 2] generation in PMNs activated with 20 ng PMA/ml. In the presence of a concentration of PMA (2 ng/ml) that by itself did not stimulate production of O[sub 2], 1 [mu]g Aroclor 1242/ml caused significant generation of O[sub 2], indicating synergy between Aroclor 1242 and PMA. Aroclor 1242 caused release of [beta]-glucuronidase from quiescent PMNs; however, in PMNs stimulated with fMLP to undergo degranulation, Aroclor 1242 inhibited release of [beta]-glucuronidase.

  17. Polychlorinated biphenyls in blue crabs from South Carolina

    SciTech Connect

    Marcus, J.M.; Mathews, T.D.

    1987-11-01

    Blue crabs are important members of the estuarine food web due to their numbers and their multiple roles as scavengers, predators and prey. Because of their omnivorous feeding characteristics, wide distribution an close association with bottom sediments, the potential exists for blue crabs to bioaccumulate pollutants residing in those sediments as has been shown for fiddler crabs. It follows that human health risk upon consumption of such crabs and biomagnification through the food web become primary concerns. During the spring of 1985, commercial crab fishermen in Beaufort County, South Carolina contacted the South Carolina Wildlife and Marine Resources Department (SCWMRD) concerning their perceptions of significantly declining catch rates in the Campbell Creek-Whale Branch area. Using knowledge of previously documented elevated polychlorinated biphenyls (PCB) levels in the sediments of the upper portion of Campbell Creek, the SCWMRD initiated analysis of crab tissue from the area to ascertain the body burdens of PCBs. Initial screening results indicated potentially significant levels of PCBs in blue crabs at which time, SCWMRD contacted the SC Department of Health and Environmental Control (SCDHEC) for more intensive study and definition of the situation. The work reported here was conducted between June and October 1985.

  18. A comprehensive approach to actual polychlorinated biphenyls environmental contamination.

    PubMed

    Risso, F; Magherini, A; Ottonelli, M; Magi, E; Lottici, S; Maggiolo, S; Garbarino, M; Narizzano, R

    2016-05-01

    Worldwide polychlorinated biphenyls (PCBs) pollution is due to complex mixtures with high number of congeners, making the determination of total PCBs in the environment an open challenge. Because the bulk of PCBs production was made of Aroclor mixtures, this analysis is usually faced by the empirical mixture identification via visual inspection of the chromatogram. However, the identification reliability is questionable, as patterns in real samples are strongly affected by the frequent occurrence of more than one mixture. Our approach is based on the determination of a limited number of congeners chosen to enable objective criteria for Aroclor identification, summing up the advantages of congener-specific analysis with the ones of total PCBs determination. A quantitative relationship is established between congeners and any single mixture, or mixtures combination, leading to the identification of the actual contamination composition. The approach, due to its generality, allows the use of different sets of congeners and any technical mixture, including the non-Aroclor ones. The results confirm that PCB environmental pollution in northern Italy is based on Aroclor. Our methodology represents an important tool to understand the source and fate of the PCBs contamination.

  19. Toxic effects of polychlorinated biphenyls on cardiac development in zebrafish.

    PubMed

    Li, Mengmeng; Wang, Xuejie; Zhu, Jingai; Zhu, Shasha; Hu, Xiaoshan; Zhu, Chun; Guo, Xirong; Yu, Zhangbin; Han, Shuping

    2014-12-01

    Polychlorinated biphenyls (PCBs) are ubiquitous environmental pollutants that may pose significant health-risks to various organisms including humans. Although the mixed PCB Aroclor 1254 is widespread in the environment, its potential toxic effect on heart development and the mechanism underlying its developmental toxicity have not been previously studied. Here, we used the zebrafish as a toxicogenomic model to examine the effects of Aroclor 1254 on heart development. We found that PCB exposure during zebrafish development induced heart abnormalities including pericardial edema and cardiac looping defects. Further malformations of the zebrafish embryo were observed and death of the larvae occurred in a time- and dose-dependent manner. Our mechanistic studies revealed that abnormalities in the arylhydrocarbon receptor, Wnt and retinoic acid signaling pathways may underlie the effects of PCBs on zebrafish heart development. Interestingly, co-administration of Aroclor 1254 and diethylaminobenzaldehyde, an inhibitor of retinaldehyde dehydrogenase, partially rescued the toxic effects of PCBs on zebrafish heart development. In conclusion, PCBs can induce developmental defects in the zebrafish heart, which may be mediated by abnormal RA signaling.

  20. Health effects of low-level exposure to polychlorinated biphenyls.

    PubMed

    Stark, A D; Costas, K; Chang, H G; Vallet, H L

    1986-10-01

    A polychlorinated biphenyl (PCB) spill resulting from a transformer explosion in Syracuse, New York, with no subsequent fire, provided an opportunity for the examination of the effects of low-level PCB exposure without the confounding presence of furans and dioxins. The incident provided 52 individuals exposed to PCB among building personnel, police, firemen, and public utility employees. Sixty-eight nonexposed were matched to the exposed group by sex, age, employer, and job description. Data were collected on the exposed relative to their activities at the spill site, their location, possible routes of exposure, duration of exposure, and subsequent health effects. Exposed and nonexposed were interviewed for past medical history and relevant symptoms. Blood chemistries were studied inclusive of SGOT, SGPT, total protein, CBC, cholesterol, and triglyceride levels, as well as a fasting blood PCB level measurement. Six weeks after the spill, exposed and nonexposed were reinterviewed and had their blood work repeated except for the CBC and PCB levels. Exposed and nonexposed laboratory results were unremarkable. Some transient skin irritation believed to be associated with PCBs was noted. There were significant PCBs in blood level trends for occupation, age, duration of exposure, and level of alcohol consumption. Triglyceride level was highly correlated with PCB level. This relationship held when age and alcohol consumption were controlled for.

  1. Elimination half-lives of polychlorinated biphenyl congeners in children.

    PubMed

    Grandjean, Philippe; Budtz-Jørgensen, Esben; Barr, Dana B; Needham, Larry L; Weihe, Pal; Heinzow, Birger

    2008-09-15

    The elimination kinetics of polychlorinated biphenyls (PCBs) in humans is difficult to assess in observational studies, because PCB exposure is never completely abolished. In a community with high dietary PCB exposures from whale blubber, we examined two groups of children with increased body burdens from breast-feeding. Follow-up was from ages 4.5 to 7.5 years (99 subjects) and 7 to 14 years (101 subjects). The calculations were performed by the use of structural equation models, with adjustment for body weight and dietary blubber intake as the main source of postnatal exposure. As a likely result of background exposures, apparent elimination half-lives were unexpectedly long when based on results from all cohort members. Subjects with exposures above the median and in the highest quartile showed half-lives of about 3-4 years for CB-138 and 4.5-5.5 years for CB-105 and CB-118; 6.5-7.5 years for CB-156, CB-170, and CB-187; and 7-9 years for CB-153 and CB-180. The longest half-lives correspond to elimination of the parent PCB solely with a daily fat excretion rate of 1-2 g, whereas shorter half-lives assume metabolic break-down.

  2. Accumulation of polychlorinated biphenyls from floodplain soils by passerine birds.

    PubMed

    Neigh, Arianne M; Zwiernik, Matthew J; Bradley, Patrick W; Kay, Denise P; Jones, Paul D; Holem, Ryan R; Blankenship, Alan L; Strause, Karl D; Newsted, John L; Giesy, John P

    2006-06-01

    Eggs, nestlings, and adults of the eastern bluebird (Sialia sialis) and house wren (Troglodytes aedon) were collected at a polychlorinated biphenyl (PCB)-contaminated site and a reference location on the Kalamazoo River (MI, USA). Eggs and nestlings of eastern bluebirds at the more contaminated location contained concentrations of 8.3 and 1.3 mg/kg, respectively, of total PCBs and 77 and 6.3 ng/kg, respectively, of 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQs). Eggs, nestlings, and adults of house wrens from the contaminated location contained 6.3, 0.77, and 3.2 mg/kg, respectively, of PCBs and 400, 63, and 110 ng/kg, respectively, of TEQs. Concentrations of total PCBs and TEQs in tissues at the more contaminated location were significantly greater than concentrations in tissues at the reference site for all tissue types of both species. Exposures of the two species studied were different, which suggests that terrestrial-based insectivorous passerine species, foraging in the same area, may have differential exposure to PCBs depending on specific foraging techniques and the insect orders that are targeted. Despite the greater accumulation of PCBs at the more contaminated location, the risk of exposure to PCBs did not exceed the threshold for adverse effects at either location.

  3. Binding of polychlorinated biphenyls to the aryl hydrocarbon receptor

    SciTech Connect

    Kafafi, S.A.; Ali, A.H.; Said, H.K. ); Afeefy, H.Y. ); Kafafi, A. G. )

    1993-10-01

    A new thermodynamic model for calculating the dissociation constants of complexes formed between the aryl hydrocarbon receptor (AhR) and polychlorinated biphenyls (PCBs) is reported. The free energies of binding of PCBs to AhR are controlled by their lipophilicites, electron affinities, and entropies. The corresponding physicochemical properties of polychlorinated dibenzo-p-dioxins and dibenzofurans also control their interactions with AhR. We present evidence supporting the hypothesis that the majority of PCBs are likely to interact with AhR in their nonplanar conformations. In addition, we demonstrate that the affinities of PCBs for AhR relative to 2,3,7,8-tetrachlorodibenzo-p-dioxin correlate with corresponding toxic equivalency factors in animals. The reported methodology is likely to be applicable to the polyhalogenated and mixed polyhalogentated bi- and terphenyls and related xenobiotics; thus, it could minimize the number of in vivo studies in laboratory animals and facilitate the identification of potentially and facilitate the identification of potentially hazardous aromatic xenobiotics.

  4. Chiral Polychlorinated Biphenyls: Absorption, Metabolism and Excretion – A Review

    PubMed Central

    Kania-Korwel, Izabela; Lehmler, Hans-Joachim

    2015-01-01

    Seventy eight out of the 209 possible polychlorinated biphenyl (PCB) congeners are chiral, nineteen of which exist under ambient conditions as stable rotational isomers that are non-superimposable mirror images of each other. These congeners (C-PCBs) represent up to 6% by weight of technical PCB mixtures and undergo considerable atropisomeric enrichment in wildlife, laboratory animals and humans. The objective of this review is to summarize our current knowledge of the processes involved in the absorption, metabolism and excretion of C-PCBs and their metabolites in laboratory animals and humans. C-PCBs are absorbed and excreted by passive diffusion, a process that, like other physicochemical processes, is inherently not atropselective. In mammals, metabolism by cytochrome P450 (P450) enzymes represents a major route of elimination for many C-PCBs. In vitro studies demonstrate that C-PCBs with a 2,3,6-trichlorosubstituion pattern in one phenyl ring are readily oxidized to hydroxylated PCB metabolites (HO-PCBs) by P450 enzymes, such as rat CYP2B1, human CYP2B6 and dog CYP2B11. The oxidation of C-PCBs is atropselective, thus resulting in a species and congener-dependent atropisomeric enrichment of C-PCBs and their metabolites. This atropisomeric enrichment of C-PCBs and their metabolites likely plays a poorly understood role in the atropselective toxicity of C-PCBs and, therefore, warrants further investigation. PMID:25651810

  5. Modeling polychlorinated biphenyl sorption isotherms for soot and coal.

    PubMed

    Jantunen, A P K; Koelmans, A A; Jonker, M T O

    2010-08-01

    Sorption isotherms (pg-ng/L) were measured for 11 polychlorinated biphenyls (PCBs) of varying molecular planarity from aqueous solution to two carbonaceous geosorbents, anthracite coal and traffic soot. All isotherms were reasonably log-log-linear, but smooth for traffic soot and staircase-shaped for coal, to which sorption was stronger and more nonlinear. The isotherms were modeled using seven sorption models, including Freundlich, (dual) Langmuir, and Polanyi-Dubinin-Manes (PDM). PDM provided the best combination of reliability and mechanistically-interpretable parameters. The PDM normalizing factor Z appeared to correlate negatively with sorbate molecular volume, dependent on the degree of molecular planarity. The modeling results supported the hypothesis that maximum adsorption capacities (Q(max)) correlate positively with the sorbent's specific surface area. Q(max) did not decrease with increasing sorbate molecular size, and adsorption affinities clearly differed between the sorbents. Sorption was consistently stronger but not less linear for planar than for nonplanar PCBs, suggesting surface rather than pore sorption. Copyright 2010 Elsevier Ltd. All rights reserved.

  6. Mortality of workers exposed to polychlorinated biphenyls--an update

    SciTech Connect

    Brown, D.P.

    1987-11-01

    A retrospective cohort mortality study of workers exposed to polychlorinated biphenyls (PCBs) in two plants manufacturing electrical capacitors was reported in 1981. The study was conducted primarily to examine the risk of cancer mortality associated with exposure to PCBs. Based on animal data, liver cancer was the disease of most interest. Due to the small number of deaths and a relatively short observation period, the study was considered inconclusive. This study has been updated by adding 7 yr of observation. The number of deaths in the study cohort has increased from 163 to 295. Mortality from all causes was found to be lower than expected (295 observed vs. 318 expected deaths) as well as mortality from all cancers (62 observed vs. 80 expected deaths). A statistically significant excess in deaths was observed in the disease category that includes cancer of the liver (primary and unspecified), gall bladder, and biliary tract (5 observed vs. 1.9 expected; p less than .05). Most of this excess was observed in women employed in one plant. Due to the small number of deaths and the variability of specific cause of death within this category, it remains difficult to interpret these findings in regard to PCB exposure.

  7. Polychlorinated biphenyls as initiators in liver carcinogenesis: resistant hepatocyte model.

    PubMed

    Espandiari, Parvaneh; Glauert, Howard P; Lehmler, Hans-Joachim; Lee, Eun Y; Srinivasan, Cidambi; Robertson, Larry W

    2003-01-01

    A modified Solt-Farber protocol was established to investigate the potential initiating activity of lower chlorinated polychlorinated biphenyl (PCB) congeners in rat liver. Two different studies were conducted in male Fisher 344 rats. PCBs investigated were PCB3, PCB12, PCB38, and PCB77 in study 1 and PCB15, PCB52, PCB77, and the combination of PCB52 and PCB77 in study 2. Rats were subjected to partial hepatectomy followed by a single dose of the suspected initiating agent, diethylnitrosamine, or vehicle. Two weeks later all groups received selection treatment consisting of three daily doses of 2-acetylaminofluorene (2-AAF) and then a single dose of carbon tetrachloride, followed by three additional daily treatments of 2-AAF via gavage. Rats were killed 2 weeks after the last treatment of 2-AAF, and the number and volume of gamma-glutamyltranspeptidase (GGT)-positive foci were determined. Among the PCBs tested, PCB3, PCB15, PCB52, and PCB77 significantly increased the number of GGT-positive foci per cm(3) of liver and per liver. Only PCB3 and PCB15 increased the volume fraction of GGT-positive foci. Histopathologic analysis of hematoxylin- and eosin-stained liver sections showed that rats with significantly increased GGT-positive foci also had extensive cellular alteration. This effect was not seen in nonselection groups. We conclude that, under the conditions and time courses of these experiments, several PCBs have initiating activity in male Fischer 344 rats.

  8. Biomagnification of polychlorinated biphenyls through a riverine food web

    SciTech Connect

    Zaranko, D.T.; Kaushik, N.K.; Griffiths, R.W.

    1997-07-01

    From 1989 to 1993, biota collected from Pottersburg Creek, London, ON, Canada were analyzed for total polychlorinated biphenyls (PCBs) and lipids. Data were analyzed by analysis of covariance (ANCOVA) with lipid as the covariate, to investigate station, time, and trophic effects on PCB accumulation in aquatic organisms. All three variables were highly significant. PCB concentrations in biota decreased along the length of the creek away from the point source. PCB concentrations in biota collected in July 1993 were not significantly different from concentrations in biota collected in July 1990, suggesting that sources into the creek have not been alleviated. The relationship between PCBs and lipid for biota from Pottersburg Creek suggests that organisms accumulate PCBs relative to their position in the food web. Fish and leeches occupying the top of the food web accumulated more PCBs than organisms occupying a lower trophic position (crayfish and oligochaetes/chironomids), indicating that biomagnification through trophic transfer (i.e., the uptake of a chemical through ingestion) is the primary mechanism governing contaminant levels in biota and not bioconcentration (i.e, the uptake of a chemical from water).

  9. Health effects of low-level exposure to polychlorinated biphenyls

    SciTech Connect

    Stark, A.D.; Costas, K.; Chang, H.G.; Vallet, H.L.

    1986-10-01

    A polychlorinated biphenyl (PCB) spill resulting from a transformer explosion in Syracuse, New York, with no subsequent fire, provided an opportunity for the examination of the effects of low-level PCB exposure without the confounding presence of furans and dioxins. The incident provided 52 individuals exposed to PCB among building personnel, police, firemen, and public utility employees. Sixty-eight nonexposed were matched to the exposed group by sex, age, employer, and job description. Data were collected on the exposed relative to their activities at the spill site, their location, possible routes of exposure duration of exposure, and subsequent health effects. Exposed and nonexposed were interviewed for past medical history and relevant symptoms. Blood chemistries were studied inclusive of SGOT, SGPT, total protein, CBC, cholesterol, and triglyceride levels, as well as a fasting blood PCB level measurement. Six weeks after the spill, exposed and nonexposed were re-interviewed and had their blood work repeated except for the CBC and PCB levels. Exposed and nonexposed laboratory results were unremarkable. Some transient skin irritation believed to be associated with PCBs was noted. There were significant PCBs in blood level trends for occupation, age, duration of exposure, and level of alcohol consumption. Triglyceride level was highly correlated with PCB level. This relationship held when age and alcohol consumption were controlled for.

  10. Inhalation of Polychlorinated Biphenyls (PCB) Produces Hyperactivity in Rats.

    PubMed

    Lombardo, John P; Berger, David F; Hunt, Anne; Carpenter, David O

    2015-01-01

    Attention deficit hyperactivity disorder (ADHD) is a serious behavioral syndrome seen in children, and more common in males than females. There is increasing evidence that prenatal and/or early life exposure to persistent organic pollutants (POP) such as polychlorinated biphenyls (PCB) is associated with increased risk of ADHD occurrence. While PCB exposure is usually attributed to ingestion of contaminated food, recent reports of elevated PCB concentrations in indoor air, especially in schools, raised concern regarding inhalation as an important route of exposure to PCB with consequent effects on neurobehavior. The effects of exposure to air contaminated with Aroclor 1248 or contaminated sediment (SED) from the St. Lawrence River were examined on operant behavior of male and female Sprague-Dawley rats. Data showed that relative to controls, vapor-phase inhalation of PCB, whether from blowing air over Aroclor 1248 or from blowing air over sediment contaminated with PCB, resulted in hyperactivity and impatience in rats, more pronounced in males than females. These results are consistent with the hypothesis that inhalation of PCB may contribute to behavioral abnormalities in children.

  11. Sex effect on polychlorinated biphenyl concentrations in fish: a synthesis

    USGS Publications Warehouse

    Madenjian, C.P.

    2011-01-01

    Polychlorinated biphenyls (PCBs) accumulate in fish primarily via food intake, and therefore, PCBs serve as a chemical tracer for food consumption. Sex differences in PCB concentrations of fish have been attributed to the following three mechanisms: (i) females losing a substantial portion of their PCB body burden during spawning and consequently their PCB concentration is considerably reduced immediately after spawning; (ii) sex differences in habitat utilization leading to sex differences in the PCB concentrations of the prey; and (iii) sex differences in gross growth efficiency, which is defined as growth divided by the amount of food consumption needed to achieve that growth. Based on my analyses and synthesis, mechanisms (i) and (ii) operate in relatively few fish populations, but can lead to mature males having PCB concentrations two to three times higher than mature female PCB concentrations. In contrast, mechanism (iii) operates in all fish populations, but typically, mechanism (iii) results in relatively modest sex differences, with mature males only between 15 and 35% higher in PCB concentration than mature females. In summary, the study of sex differences in PCB concentrations of fish has led to insights into fish behaviour and fish physiology.

  12. Elimination Half-lives of Polychlorinated Biphenyl Congeners in Children

    PubMed Central

    Grandjean, Philippe; Budtz-Jørgensen, Esben; Barr, Dana B.; Needham, Larry L.; Weihe, Pal; Heinzow, Birger

    2008-01-01

    The elimination kinetics of polychlorinated biphenyls (PCBs) in humans is difficult to assess in observational studies, because PCB exposure is never completely abolished. In a community with high dietary PCB exposures from whale blubber, we examined two groups of children with increased body burdens from breast-feeding. Follow-up was from ages 4.5 years to 7.5 years (99 subjects) and 7 to 14 years (101 subjects). The calculations were performed by the use of structural equation models, with adjustment for body weight and dietary blubber intake as the main source of postnatal exposure. As a likely result of background exposures, apparent elimination half-lives were unexpectedly long when based on results from all cohort members. Subjects with exposures above the median and in the highest quartile showed half-lives of about 3-4 years for CB-138, and 4.5-5.5 years for CB-105 and CB-118; 6.5-7.5 years for CB-156, CB-170, and CB-187; and 7-9 years for CB-153 and CB-180. The longest half-lives correspond to elimination of the parent PCB solely with a daily fat excretion rate of 1-2 g, while shorter half-lives assume metabolic break-down. PMID:18853821

  13. Polychlorinated biphenyl congeners as markers of toxic equivalents of polychlorinated biphenyls, dibenzo-p-dioxins and dibenzofurans in breast milk.

    PubMed

    Glynn, A W; Atuma, S; Aune, M; Darnerud, P O; Cnattingius, S

    2001-07-01

    In breast milk, concentrations of polychlorinated biphenyls (PCBs) are higher than those of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs), making PCB analyses less time-consuming and expensive. We searched for PCB "markers" of PCDD/DF concentrations, by studying associations between concentrations of PCB and PCDD/DFs (expressed as toxic equivalents, TEQs) in breast milk from 27 women (primiparas, 22-35 years). These women donated breast milk in 1996-1999 together with 183 other primiparas from Uppsala County, Sweden. Regression analyses showed that both dioxin-like and non-dioxin-like penta- to hepta-chlorinated PCBs could be used as markers of TEQ concentrations in this group of women, in some cases after age adjustment of the regressions. The strong positive association between concentrations of dioxin-like PCB/DD/DFs and non-dioxin-like PCBs will in future epidemiological studies make it difficult to separate Ah receptor-dependent effects from non-Ah receptor-dependent effects. With the use of regression equations and concentrations in breast milk samples collected in 1994, TEQ concentrations were estimated in the 1994 samples. Comparisons between estimated and measured concentrations indicated that associations between concentrations of marker substances and TEQs should be determined separately within each study population, in order to obtain reliable TEQ exposure assessments from PCB markers.

  14. Novel biphenyl ester derivatives as tyrosinase inhibitors: Synthesis, crystallographic, spectral analysis and molecular docking studies

    PubMed Central

    Kwong, Huey Chong; Chidan Kumar, C. S.; Mah, Siau Hui; Chia, Tze Shyang; Loh, Zi Han; Chandraju, Siddegowda; Lim, Gin Keat

    2017-01-01

    Biphenyl-based compounds are clinically important for the treatments of hypertension and inflammatory, while many more are under development for pharmaceutical uses. In the present study, a series of 2-([1,1'-biphenyl]-4-yl)-2-oxoethyl benzoates, 2(a-q), and 2-([1,1'-biphenyl]-4-yl)-2-oxoethyl pyridinecarboxylate, 2(r-s) were synthesized by reacting 1-([1,1'-biphenyl]-4-yl)-2-bromoethan-1-one with various carboxylic acids using potassium carbonate in dimethylformamide at ambient temperature. Single-crystal X-ray diffraction studies revealed a more closely packed crystal structure can be produced by introduction of biphenyl moiety. Five of the compounds among the reported series exhibited significant anti-tyrosinase activities, in which 2p, 2r and 2s displayed good inhibitions which are comparable to standard inhibitor kojic acid at concentrations of 100 and 250 μg/mL. The inhibitory effects of these active compounds were further confirmed by computational molecular docking studies and the results revealed the primary binding site is active-site entrance instead of inner copper binding site which acted as the secondary binding site. PMID:28241010

  15. Chronic oral exposure of rainbow trout (Salmo gairdneri) to a polychlorinated biphenyl (Aroclor 1254): pathological effects.

    PubMed Central

    Nestel, H; Budd, J

    1975-01-01

    Groups of eight rainbow trout (Salmo gairdneri) were fed rations containing 0 ppm, 1 ppm, 10 ppm and 100 ppm of the polychlorinated biphenyl, Aroclor 1254, over a period of up to 330 days. Growth rates were unaffected by these levels. Pathological changes were found in the kidneys of 13 fish on the polychlorinated biphenyl ration. Foci of nephrosis with cellular or granular cast formation were seen. The greatest number of cases occured in fish at the 10 ppm concentration. An increase in the number of hepatocytes per unit area was related to the greater concentration of polychlorinated biphenyls in the diet. A reduction in the amount of white pulp in the spleen was observed in 23 of 27 fish on the 10 ppm and 100 ppm diets. The fish with nephrosis had reduced splenic white pulp and lowered white cell counts. Fish fed the 1 ppm and 10 ppm levels had mean tissue residues of 1.4 and 2.3 ppm polychlorinated biphenyl respectively. Fish on the 100 ppm ration had a mean value of 80.1 ppm polychlorinated biphenyl content. Images Fig. 1. PMID:804980

  16. Reductive debromination of the commercial polybrominated biphenyl mixture firemaster BP6 by anaerobic microorganisms from sediments

    SciTech Connect

    Morris, P.J.; Quensen, J.F. III; Tiedje, J.M.; Boyd, S.A. )

    1992-10-01

    Anaerobic microorganisms eluted from three sediments, one contaminated with polybrominated biphenyls (PBBs) and two contaminated with polychlorinated biphenyls, were compared for their ability to debrominate the commercial PBB mixture Firemaster. These microorganisms were incubated with reduced anaerobic mineral medium and noncontaminated sediment amended with Firemaster. Firemaster averages six bromines per biphenyl molecule; four of the bromines are substituted in the meta or para position. The inocula from all three sources were able to debrominate the meta and para positions. Microorganisms from the Pine River (St. Louis, Mich.) contaminated with Firemaster, the Hudson River (Hudson Falls, N.Y.) contaminated with Aroclor 1242, and Silver Lake (Pittsfield, Mass.) contaminated with Aroclor 1260 removed 32, 12, and 3% of the meta plus para bromines, respectively, after 32 weeks of incubation. This suggests that previous environmental exposure to PBBs enhances the debromination capability of the sediment microbial community through selection for different strains of microorganisms. The Pine River inoculum removed an average of 1.25 bromines per biphenyl molecule during a 32-week incubation period, resulting in a mixture potentially more accessible to aerobic degradation processes. No ortho bromine removal was observed. However, when Firemaster was incubated with Hudson River microorganisms that had been repeatedly transferred on a pyruvate medium amended with Aroclor 1242, 17% of the meta and para bromines were removed after 16 weeks of incubation and additional debromination products, including 2-bromobiphenyl and biphenyl, were detected.

  17. Factors influencing combined exposure to three indicator polychlorinated biphenyls in an adult cohort from Bolivia.

    PubMed

    Arrebola, J P; Mutch, E; Cuellar, M; Quevedo, M; Claure, E; Mejía, L M; Fernández-Rodríguez, M; Freire, C; Olea, N; Mercado, L A

    2012-07-01

    Polychlorinated biphenyls are persistent organic pollutants that have been used for decades in several industrial applications. Although production of polychlorinated biphenyls was restricted from the 1970s in most countries, substantial amounts remain in old equipment and buildings and they have been detected in various environmental and biological matrices. The main objective of this study was to analyze predictors of the combined exposure to three non-dioxin-like polychlorinated biphenyls (congeners 138, 153 and 180) in serum and adipose tissue from an adult cohort (n=112) living in the city of Santa Cruz de la Sierra (Bolivia) and surrounding towns/villages. A second aim was to identify modifiers that might influence the statistical associations found, using crude, partially-adjusted, and global multiple linear regression models. Main predictors of serum concentrations were occupation and fatty food consumption, while those for adipose tissue concentrations included age, smoking habit, fatty food consumption, and residence. The differences between the two matrices might be derived from their biological meaning, given that adipose tissue concentrations are an indicator of chronic exposure to polychlorinated biphenyls while serum levels are a good predictor of ongoing exposure and the mobilization of polychlorinated biphenyls stored in fatty tissues. Body mass index was found to be an important modifier of these associations.

  18. Worker exposure to polychlorinated biphenyls in elastic polysulphide sealant renovation.

    PubMed

    Kontsas, Helena; Pekari, Kaija; Riala, Riitta; Bäck, Beatrice; Rantio, Tiina; Priha, Eero

    2004-01-01

    Worker exposure to polychlorinated biphenyls (PCBs) in renovation of prefabricated houses was assessed by biological monitoring of 24 PCB congeners including the 10 most abundant PCBs in elastic polysulphide sealants. Serum samples from 22 exposed and 21 non-exposed men were analysed using gas chromatography-mass spectrometry with negative chemical ionization. Total PCB concentration of 24 PCB congeners in workers' serum varied between 0.6 and 17.8 microg/l (mean 3.9 microg/l, median 1.9 microg/l). The Finnish upper reference limit for occupationally non-exposed persons (3 microg/l) was exceeded in the serum samples of 10 workers. Concentrations for non-exposed persons were 0.3-3.0 microg/l (mean 1.7 microg/l, median 1.5 microg/l). The concentration for the sum of the 10 most abundant PCB congeners in elastic polysulphide sealants in serum samples taken in autumn after the renovation season was 2-10 times higher than in samples from the same workers (n=5) taken in the previous spring. The concentrations of PCB congeners PCB 28, 52, 77, 101, 138, 153 and 180 in hygienic samples taken from the breathing zone of the workers were low, ranging from not detected to 3.1 microg/m3. The concentrations of PCB 28 and 52 in sera were positively correlated with the concentrations in air samples taken from the breathing zone of six workers (r=0.70 and 0.80).

  19. A compromised liver alters polychlorinated biphenyl-mediated toxicity.

    PubMed

    Wahlang, Banrida; Perkins, Jordan T; Petriello, Michael C; Hoffman, Jessie B; Stromberg, Arnold J; Hennig, Bernhard

    2017-02-02

    Exposure to environmental toxicants namely polychlorinated biphenyls (PCBs) is correlated with multiple health disorders including liver and cardiovascular diseases. The liver is important for both xenobiotic and endobiotic metabolism. However, the responses of an injured liver to subsequent environmental insults has not been investigated. The current study aims to evaluate the role of a compromised liver in PCB-induced toxicity and define the implications on overall body homeostasis. Male C57Bl/6 mice were fed either an amino acid control diet (CD) or a methionine-choline deficient diet (MCD) during the 12-week study. Mice were subsequently exposed to either PCB126 (4.9mg/kg) or the PCB mixture, Arcolor1260 (20mg/kg) and analyzed for inflammatory, calorimetry and metabolic parameters. Consistent with the literature, MCD diet-fed mice demonstrated steatosis, indicative of a compromised liver. Mice fed the MCD-diet and subsequently exposed to PCB126 showed observable wasting syndrome leading to mortality. PCB126 and Aroclor1260 exposure worsened hepatic fibrosis exhibited by the MCD groups. Interestingly, PCB126 but not Aroclor1260 induced steatosis and inflammation in CD-fed mice. Mice with liver injury and subsequently exposed to PCBs also manifested metabolic disturbances due to alterations in hepatic gene expression. Furthermore, PCB exposure in MCD-fed mice led to extra-hepatic toxicity such as upregulated circulating inflammatory biomarkers, implicating endothelial cell dysfunction. Taken together, these results indicate that environmental pollution can exacerbate toxicity caused by diet-induced liver injury which may be partially due to dysfunctional energy homeostasis. This is relevant to PCB-exposed human cohorts who suffer from alcohol or diet-induced fatty liver diseases.

  20. Immunotoxicity Monitoring in a Population Exposed to Polychlorinated Biphenyls

    PubMed Central

    Haase, Hajo; Fahlenkamp, Astrid; Schettgen, Thomas; Esser, Andre; Gube, Monika; Ziegler, Patrick; Kraus, Thomas; Rink, Lothar

    2016-01-01

    The relationship between polychlorinated biphenyl (PCB) burden and several indicators of immune function was investigated as part of the HELPcB (Health Effects in High-Level Exposure to PCB) program, offering bio-monitoring to workers, relatives, and neighbors exposed to PCBs by a German transformers and capacitors recycling company. The present retrospective observational study evaluates the correlation of plasma levels of total PCBs, five indicator congeners (28, 101, 138, 153, 180), and seven dioxin-like congeners (105, 114, 118, 156, 157, 167, 189) with several parameters of immune function. The cross-sectional study was performed immediately after the end of exposure (258 subjects), and one (218 subjects), and two (177 subjects) years later. At the first time point, measurements showed significant positive correlation between congeners with low to medium chlorination and the relative proportion of CD19 positive B-cells among lymphocytes, as well as a negative correlation of PCB114 with serum IgM, and of PCB 28 with suppressor T-cell and NK-cell numbers. Congeners with a high degree of chlorination, in particular PCB157 and 189, were positively associated with expression of the activation marker CD25 on T-cells in the cohort of the second time point. No associations between PCB levels and IFN-y production by T-cells and killing by NK-cells were found. In conclusion, there were several effects on the cellular composition of adaptive immunity, affecting both T- and B-cells. However, the values were not generally outside the reference ranges for healthy adult individuals and did not indicate overt functional immunodeficiency, even in subjects with the uppermost PCB burden. PMID:27005643

  1. Attenuation of polychlorinated biphenyl sorption to charcoal by humic acids.

    PubMed

    Koelmans, Albert A; Meulman, Brendo; Meijer, Thijs; Jonker, Michiel T O

    2009-02-01

    Strong sorption to black carbon may limit the environmental risks of organic pollutants, but interactions with cosorbing humic acid (HA) may interfere. We studied the attenuative effect of HA additions on the sorption of polychlorinated biphenyls (PCBs) to a charcoal. "Intrinsic" sorption to HA-amended charcoal was calculated by subtracting the sorption contribution of HA from the total sorption to charcoal and HA. Association of PCBs with HA was proportional to hydrophobicity. However, the planar PCBs 77 and 126 had an additional 2-4 times stronger association than expected from hydrophobicity alone. Sorption isotherms for the raw charcoal fitted slightly better to a three-parameter Polanyi-Dubinin-Manes model than to a two-parameter Langmuir model. Preloading the charcoal with 1-75 mg of HA/g of charcoal increasingly attenuated sorption to charcoal with up to a factor of 10. The resultant isotherms could be described adequately with the Freundlich model. Isotherm nonlinearity increased with HA loading, suggesting increased sorption competition between HA and PCBs. Attenuation was negligible in the PCB picogram per liter to nanogram per liter range and increased at higher PCB concentrations, which points to saturation of binding sites on the charcoal. Attenuation was highest for planar congeners, which suggests an additional site blockage mechanism. These variations due to HA loading and PCB concentration can explain the variability in attenuation reported in earlier work and imply that the use of constant "attenuation factors" to adjust sorption coefficients determined for pure carbonaceous materials in order to apply them to field situations may not be warranted.

  2. Plasma Polychlorinated Biphenyl Concentrations and Immune Function in Postmenopausal Women☆

    PubMed Central

    Spector, June T.; De Roos, Anneclaire J.; Ulrich, Cornelia M.; Sheppard, Lianne; Sjodin, Andreas; Wener, Mark H.; Wood, Brent; McTiernan, Anne

    2014-01-01

    Background Polychlorinated biphenyl (PCB) exposure has been associated with non-Hodgkin lymphoma in several studies, and the immune system is a potential mediator. Objectives We analyzed associations of plasma PCBs with immune function measures. We hypothesized that higher plasma PCB concentrations are associated with lower immune function cross-sectionally, and that increases in PCB concentrations over a one year period are associated with decreases in immune function. Methods Plasma PCB concentrations and immune function [natural killer (NK) cell cytotoxicity and PHA-induced T-lymphocyte proliferation (PHA-TLP)] were measured at baseline and one year in 109 postmenopausal overweight women participating in an exercise intervention study in the Seattle, Washington (USA) area. Mixed models, with adjustment for body mass index and other potential confounders, were used to estimate associations of PCBs with immune function cross-sectionally and longitudinally. Results Associations of PCBs with immune function measures differed across groups of PCBs (e.g., medium- and high-chlorinated and dioxin-like [mono-ortho substituted]) and by the time frame for the comparison (cross-sectional vs. longitudinal). Higher concentrations of medium- and high-chlorinated PCBs were associated with higher PHA-TLP cross-sectionally but not longitudinally. The mean decrease in 0.5 μg/mL PHA-TLP per 50.0 pmol/g-lipid increase in dioxin-like PCBs over one year was 51.6 (95% confidence interval 2.7, 100.5; P=0.039). There was no association between plasma PCBs and NK cytotoxicity. Conclusions These results do not provide strong evidence of impaired cellular immunity from PCB exposure. Larger longitudinal studies with greater variability in PCB exposures are needed to further examine temporal associations of PCBs with immune function. PMID:24721136

  3. Polychlorinated biphenyls in Spanish adults: Determinants of serum concentrations

    SciTech Connect

    Agudo, Antonio; Goni, Fernando; Etxeandia, Arsenio; Vives, Asuncion; Millan, Esmeralda; Lopez, Raul; Amiano, Pilar; Ardanaz, Eva; Barricarte, Aurelio; Dolores Chirlaque, M.; Dorronsoro, Miren; Jakszyn, Paula; Larranaga, Nerea; Martinez, Carmen; Navarro, Carmen; Rodriguez, Laudina; and others

    2009-07-15

    Background: Polychlorinated biphenyls (PCBs) are persistent compounds that may pose an environmental hazard to humans, food being the main source of exposure for the general population. Objective: To measure the serum concentrations of the main PCBs in subjects from the general population in Spain, and to assess potential determinants of such concentrations. Methods: Serum was obtained from blood samples of 953 subjects aged 35-64 years, residents in five Spanish regions (three from the North and two from the South), randomly selected from the EPIC-Spain cohort. Blood collection took place during 1992-1996 and four PCB congeners (118, 138, 153 and 180) were determined by means of gas chromatography with electron-capture detection (GC-ECD). Results: The concentration of total PCBs was 459 ng/g lipids (or 3.1 {mu}g/l); the corresponding figures for PCB 153 were 186 ng/g lipids and 1.25 {mu}g/l. Men had higher values than women, PCB levels increased with age, and serum concentration of PCBs was higher in northern regions. Body mass index (BMI) was inversely related to PCB concentrations, and fish intake was the dietary factor showing the greatest association with serum PCBs. The pattern described was similar for each congener separately. Conclusions: We found concentrations similar to those reported in European countries where blood collection was carried during the same period. Regional differences within Spain are not fully explained by anthropometric or dietary factors. The inverse association with BMI suggests that in the mid-1990s there was still ongoing or recent exposure to PCBs in Spain.

  4. Polybrominated diphenyl ethers and polybrominated biphenyls in Australian sewage sludge.

    PubMed

    Clarke, Bradley; Porter, Nichola; Symons, Robert; Marriott, Philip; Ades, Peter; Stevenson, Gavin; Blackbeard, Judy

    2008-10-01

    This paper presents a brief review of the international scientific literature of polybrominated diphenyl ethers (PBDEs) and polybrominated biphenyls (PBBs) in sewage sludge and a survey of these compounds in sewage sludge from 16 Australian wastewater treatment plants (WWTPs). The SigmaPBDE mean concentration in the Australian study was 1137microgkg(-1) dry weight (d.w.) (s.d. 1116) and ranged between 5 and 4 230microgkg(-1)d.w. The urban mean of 1308microgkg(-1) (s.d. 1320) and the rural mean of 911microgkg(-1) (s.d. 831) are not statistically different and are similar to levels in European sludges. Principal components analysis was performed on the data set and revealed that 76% of the data variation could be explained by two components that corresponded to overall concentration of the pentaBDE and the decaBDE commercial formulations. An analysis of variance was performed comparing PBDEs levels at three WWTPs over the years 2005 and 2006, finding differences between treatment plants (BDE-47) but no significant difference in PBDE levels in the years 2005 and 2006. Low levels of BB-153 were detected in all samples of this survey (n=16); mean 0.6microgkg(-1)d.w. (s.d. 0.5). This compound has rarely been reported in any other study of sewage sludges undertaken outside Australia. This work highlights the need for a risk assessment of PBDEs in sewage sludge when used for land application, taking into account typical levels found in Australian sludges and soils.

  5. Binding properties of halogenated biphenyls to cells and macromolecules

    SciTech Connect

    Pepe, M.G.

    1982-01-01

    The interaction of polychlorinated biphenyls (PCB) with serum proteins may help explain the cellular incorporation of PCB as the effect of PCB on thyroid hormone function. PCB reduces serum thyroxine and triiodothyronine levels in rats; the mechanism for this effect is unknown. The initial distribution of PCB from blood to tissue is rapid and depends on blood perfusion and tissue affinity; however, the translocation of unmetabolized PCB from its initial storage sites to adipose tissue may depend on serum and cellular protein interactions. Therefore, the ability of PCB to displace triiodothyronine binding to albumin and antibodies, as well as the effect of binding to serum proteins as a mechanism for cellular incorporation was measured. PCB binding to albumin showed both high and low affinity binding sites. This binding was able to prevent triiodothyronine binding to albumin. The distribution of PCB inserum showed that lipoproteins contained 94% of the total /sup 14/C PCB added, while 5% of the /sup 14/C PCB was bound to albumin. The in vitro binding of /sup 14/C PCB to serum obtained from rats pretreated with PCB in their diets for 6 months showed a significant decrease (p < 0.05) in binding compared to serum from untreated controls. This reduction in binding was caused by a decrease (p < 0.05) in total serum protein. Cellular incorporation of PCB is dependent on cell type, integrity of the plasma membrane and serum proteins. The in vitro incorporation of /sup 14/C PCB was higher (p < 0.05) in liver, adrenal and adipose cells than pituitary and thyroid cells.

  6. Polychlorinated biphenyls: New evidence from the last decade

    PubMed Central

    Faroon, Obaid; Ruiz, Patricia

    2015-01-01

    Millions of pounds of polychlorinated biphenyl (PCB) compounds have been produced in multiple countries for industrial applications over the last several decades. PCB exposure induces various adverse health effects in animals and humans. Environmental and occupational exposures to PCBs have been associated with liver, kidney, endocrine, and neurodevelopmental adverse effects. We have collected and reviewed animal and human data cited in the U.S. National Library of Medicine from 2000–2010. In brief, our review shows new evidence that demonstrates: In animal studies, exposure to one of the PCBs, A1221, induces a significant alteration of serum luteinizing hormone. The effects were more profound in the F2 generation, particularly with respect to fluctuations in hormones and reproductive tract tissues across the estrous cycle. Morphological analyses of brain tissue from rats exposed to A1254 confirmed earlier work that showed the relative size of the intra- and infra-pyramidal (II-P) mossy fibers was smaller than in controls, and reduction in growth was selective for the II-P mossy fibers. PCB exposure increased anogenital distance and prostate size but decreased epididymal weight, epididymal sperm count, and motile epididymal sperm count. No effects were observed on testicular weight or size. The epidemiological data showed an association between diabetes mellitus prevalence and elevated concentrations of PCB-153. Additionally, prenatal PCB exposure studies were associated with a smaller thymic index at birth and could adversely affect immune responses to childhood vaccinations and resistance to respiratory infections. PCB exposure was also reported to adversely affect enamel development in children in a dose-dependent manner. Because PCBs and their metabolites are potential health hazards, understanding the risk factors associated with individual PCBs, PCB mixtures, and PCB metabolites is important. PCB exposures of vulnerable populations (pregnant women, fetuses

  7. Human Receptor Activation by Aroclor 1260, a Polychlorinated Biphenyl Mixture

    PubMed Central

    Wahlang, Banrida; Falkner, K. Cameron; Clair, Heather B.; Al-Eryani, Laila; Prough, Russell A.; States, J. Christopher; Coslo, Denise M.; Omiecinski, Curtis J.; Cave, Matthew C.

    2014-01-01

    Polychlorinated biphenyls (PCBs) are persistent environmental toxicants, present in 100% of U.S. adults and dose-dependently associated with obesity and non-alcoholic fatty liver disease (NAFLD). PCBs are predicted to interact with receptors previously implicated in xenobiotic/energy metabolism and NAFLD. These receptors include the aryl hydrocarbon receptor (AhR), pregnane xenobiotic receptor (PXR), constitutive androstane receptor (CAR), peroxisome proliferator-activated receptors (PPARs), liver-X-receptor (LXRα), and farnesoid-X-receptor (FXR). This study evaluates Aroclor 1260, a PCB mixture with congener composition mimicking that of human adipose tissue, and selected congeners, as potential ligands for these receptors utilizing human hepatoma-derived (HepG2) and primate-derived (COS-1) cell lines, and primary human hepatocytes. Aroclor 1260 (20 μg/ml) activated AhR, and PCB 126, a minor component, was a potent inducer. Aroclor 1260 activated PXR in a simple concentration-dependent manner at concentrations ≥10 μg/ml. Among the congeners tested, PCBs 138, 149, 151, 174, 183, 187, and 196 activated PXR. Aroclor 1260 activated CAR2 and CAR3 variants at lower concentrations and antagonize CAR2 activation by the CAR agonist, CITCO, at higher concentrations (≥20 μg/ml). Additionally, Aroclor 1260 induced CYP2B6 in primary hepatocytes. At subtoxic doses, Aroclor 1260 did not activate LXR or FXR and had no effect on LXR- or FXR-dependent induction by the agonists T0901317 or GW4064, respectively. Aroclor 1260 (20 μg/ml) suppressed PPARα activation by the agonist nafenopin, although none of the congeners tested demonstrated significant inhibition. The results suggest that Aroclor 1260 is a human AhR, PXR and CAR3 agonist, a mixed agonist/antagonist for CAR2, and an antagonist for human PPARα. PMID:24812009

  8. Lipopolysaccharide-induced hepatic injury is enhanced by polychlorinated biphenyls.

    PubMed Central

    Brown, A P; Schultze, A E; Holdan, W L; Buchweitz, J P; Roth, R A; Ganey, P E

    1996-01-01

    After intravenous administration of bacterial lipopolysaccharide (LPS) to rats, polymorphonuclear neutrophils (PMNs) rapidly accumulate in the liver, and midzonal hepatic necrosis is prominent by 6 hr. PMNs are required for the development of hepatic injury in rats. Certain polychlorinated biphenyls (PCBs) can activate PMNs, resulting in production of superoxide anion (O2-.) and release of cytolytic factors from granules. This raises the possibility that PCB exposure might enhance PMN-mediated tissue injury, such as LPS-induced hepatotoxicity. We treated female Sprague-Dawley rats with a minimally toxic dose of LPS in saline (2 mg/kg, intravenous) and 90 min later exposed them to Aroclor 1248 (50 mg/kg, intraperitoneal), a mixture of PCBs. The animals were killed 6 hr after LPS administration, and hepatic injury was assessed. Neither LPS nor Aroclor 1248 alone produced liver injury. Co-treatment with LPS and Aroclor 1248 resulted in pronounced liver injury as demonstrated from increased activities of alanine aminotransferase and isocitrate dehydrogenase in plasma. Histological evaluation indicated increased severity of hepatic necrosis in rats receiving both LPS and Aroclor 1248. Hepatic accumulation of PMNs, normally observed after LPS, was not altered by co-exposure to PCBs. Aroclor 1248 stimulated rat PMNs in vitro to produce O2-. and to degranulate. In addition, PMN-mediated cytotoxicity to isolated rat hepatocytes in culture was increased upon addition of Aroclor 1248. PCBs activate PMNs in vitro and increase PMN-dependent hepatocellular damage in vitro and after LPS treatment in vivo. PCBs may act in vivo as an additional inflammatory stimulus to activate PMNs to become cytotoxic, resulting in increased tissue injury. Images Figure 1. Figure 2. A Figure 2. B Figure 3. Figure 4. A Figure 4. B Figure 5. Figure 6. PMID:8793352

  9. Pan-arctic river fluxes of polychlorinated biphenyls.

    PubMed

    Carrizo, Daniel; Gustafsson, Örjan

    2011-10-01

    Observations of polychlorinated biphenyls (PCB) concentrations in fluvial surface sediments near the mouths of the six Great Arctic Rivers (GARs; Ob, Yenisey, Lena, Indigirka, Kolyma, and Mackenzie) were combined with annual dissolved organic carbon (DOC) and particulate organic carbon (POC) loadings and hydraulic discharge to estimate the pan-Arctic river flux of PCBs. The highest total-phase fluxes of ∑(13)PCB were found for the Ob River, with 184 kg/yr and the smallest for the Indigirka River with 3.9 kg/yr. Consistent with a continent-scale trend among the Eurasian GARs of increasing POC concentrations eastward, which is extending to the North American Mackenzie River, a general shift in the estimated PCB partitioning from dissolved to particle-associated flux was found toward the east. Pentachlorinated and hexachlorinated PCBs constituted the majority (>70%) of the total PCB fluxes in the Eurasian Rivers. In contrast, trichlorinated and tetrachlorinated congeners were the most abundant in the Mackenzie (≈ 75%). The total ∑(13)PCB fluxes from the pan-Arctic rivers are here estimated to be ∼0.4 tonne/yr. This is geochemically consistent with the inventory of total PCBs in the Polar Mixed Layer of the entire Arctic Ocean (0.39 tonne) and about a factor 2 less than two new estimates of the PCB settling export to Arctic subsurface waters. Hence, the yearly Great Arctic River PCB fluxes only represent 0.001% of the historical PCB emission into the global environment. To our knowledge, this is the first estimate of circum-Arctic river flux of any organic pollutant based on a comprehensive investigation of the pollutants in several rivers and it contributes toward a more complete understanding of large-scale contaminant cycling in the Arctic.

  10. Striped bass stocks and concentrations of polychlorinated biphenyls

    USGS Publications Warehouse

    Fabrizio, Mary C.; Sloan, Ronald J.; O'Brien, John F.

    1991-01-01

    Harvest restrictions on striped bass Morone saxatilis fisheries in Atlantic coastal states were relaxed in 1990, but consistent, coastwide regulations of the harvest have been difficult to implement because of the mixed-stock nature of the fisheries and the recognized contamination of Hudson River fish by polychlorinated biphenyls (PCBs). We examined PCB concentrations and stock of origin of coastal striped bass to better understand the effects of these two factors on the composition of the harvest. The probability of observing differences in PCB concentration among fish from the Hudson River stock and the 'southern' group (Chesapeake Bay and Roanoke River stocks combined) was investigated with the logit model (a linear model for analysis of categorical data). Although total PCB concentrations were highly variable among fish from the two groups, striped bass classified as Hudson River stock had a significantly greater probability of having PCB concentrations equal to or greater than 2.00 mg/kg than did fish belonging to the southern group for all age- and size-classes examined. There was a significantly greater probability of observing total PCB concentrations equal to or exceeding 2.00 mg/kg in fish that were 5, 6, and 7 or more years old, and this probability increased linearly with age. We observed similar results when we examined the effect of size on total PCB concentration. The minimum-size limit estimated to permit escapement of fish to sustain stock production is 610 mm total length. Unless total PCB concentrations decrease in striped bass, it is likely that many harvestable fish will have concentrations that exceed the tolerance limit set by the U.S. Food and Drug Administration.

  11. Perinatal exposure to polychlorinated biphenyls alters social behaviors in rats

    PubMed Central

    Jolous-Jamshidi, Banafsheh; Cromwell, Howard C.; McFarland, Ashley M.; Meserve, Lee A.

    2014-01-01

    Perinatal exposure to polychlorinated biphenyls (PCBs) leads to significant alterations of neural and hormonal systems. These alterations have been shown to impair motor and sensory development. Less is known about the influence of PCB exposure on developing emotional and motivational systems involved in social interactions and social learning. The present study examined the impact of perinatal PCB exposure (mixture of congeners 47 and 77) on social recognition in juvenile animals, conspecific-directed investigation in adults and on neural and hormonal systems involved in social functions. We used a standard habituation–dishabituation paradigm to evaluate juvenile recognition and a social port paradigm to monitor adult social investigation. Areal measures of the periventricular nucleus (PVN) of the hypothalamus were obtained to provide correlations with related hormone and brain systems. PCB exposed rats were significantly impaired in social recognition as indicated by persistent conspecific-directed exploration by juvenile animals regardless of social experience. As adults, PCB exposure led to a dampening of the isolation-induced enhancement of social investigation. There was not a concomitant alteration of social investigation in pair-housed PCB exposed animals at this stage of development. Interestingly, PVN area was significantly decreased in juvenile animals exposed to PCB during the perinatal period. Shifts in hypothalamic regulation of hormones involved in social behavior and stress could be involved in the behavioral changes observed. Overall, the results suggest that PCB exposure impairs context or experience-dependent modulation of social approach and investigation. These types of social-context deficits are similar to behavioral deficits observed in social disorders such as autism and other pervasive developmental disorders. PMID:20813172

  12. Effects of polybrominated biphenyls on the excretion of steroids.

    PubMed

    Willett, L B; Schanbacher, F L; Moorhead, P D

    1983-05-01

    When polybrominated biphenyls (fireMaster BP-6, PBB) are ingested by cattle, they have been shown to alter hepatic enzyme systems, and produce renal lesions with chronic high exposure. These changes provide mechanisms for alteration of the metabolism and clearance of steroid hormones that might then affect reproductive function. This study was conducted to examine the effects of PBB on the excretion of radiolabel from injected estradiol-17 beta and progesterone. Toxicity was induced by dosing two Holstein cows with 25 g of fireMaster BP-6/d for 39 or 50 d. Single iv injections of 35 microCi [4-14C] progesterone and 400 microCi [2,4,6,7-3H] estradiol-17 beta were given on d -5, 10, 30 and 38 or 48 relative to dosing. Last injections were given when animals were terminally toxic. Clinical signs and necropsy findings confirmed the typical toxic syndrome and renal lesions. Excretion of 14C was primarily in feces, while 3H appeared in both urine and feces. As toxicosis developed, the excretion of steroids in feces was delayed as anorexia reduced mass and rate of passage of feces. This had little effect on the amount of steroid excreted and the rate of urinary excretion was affected only minimally. Recovery of both radiolabels declined 10 to 20% by d 30 of dosing as excretion rate was reduced from pre-PBB dosing. Excretion declined sharply when animals were moribund. Despite developing toxicosis, both animals continued to have estrous cycles with normal periodicity.

  13. Immunotoxicity Monitoring in a Population Exposed to Polychlorinated Biphenyls.

    PubMed

    Haase, Hajo; Fahlenkamp, Astrid; Schettgen, Thomas; Esser, Andre; Gube, Monika; Ziegler, Patrick; Kraus, Thomas; Rink, Lothar

    2016-03-08

    The relationship between polychlorinated biphenyl (PCB) burden and several indicators of immune function was investigated as part of the HELPcB (Health Effects in High-Level Exposure to PCB) program, offering bio-monitoring to workers, relatives, and neighbors exposed to PCBs by a German transformers and capacitors recycling company. The present retrospective observational study evaluates the correlation of plasma levels of total PCBs, five indicator congeners (28, 101, 138, 153, 180), and seven dioxin-like congeners (105, 114, 118, 156, 157, 167, 189) with several parameters of immune function. The cross-sectional study was performed immediately after the end of exposure (258 subjects), and one (218 subjects), and two (177 subjects) years later. At the first time point, measurements showed significant positive correlation between congeners with low to medium chlorination and the relative proportion of CD19 positive B-cells among lymphocytes, as well as a negative correlation of PCB114 with serum IgM, and of PCB 28 with suppressor T-cell and NK-cell numbers. Congeners with a high degree of chlorination, in particular PCB157 and 189, were positively associated with expression of the activation marker CD25 on T-cells in the cohort of the second time point. No associations between PCB levels and IFN-y production by T-cells and killing by NK-cells were found. In conclusion, there were several effects on the cellular composition of adaptive immunity, affecting both T- and B-cells. However, the values were not generally outside the reference ranges for healthy adult individuals and did not indicate overt functional immunodeficiency, even in subjects with the uppermost PCB burden.

  14. Congener-specific polychlorinated biphenyls in cetaceans from Taiwan waters.

    PubMed

    Chou, C C; Chen, Y N; Li, C S

    2004-11-01

    During 2000 to 2001, a total of 73 blubber samples from 13 species of stranded or accidentally captured cetaceans were collected from Taiwan coastal waters for polychlorinated biphenyl (PCB) analysis. After homogenization, saponification, liquid-liquid extraction, and silica-gel solid-phase extraction, PCB concentrations were determined by gas chromatography/mass spectrometry. Total concentrations of 19 PCB congeners (SigmaPCBs) were between 0.23 microg/g lipid weight of Risso's dolphin to 33.73 microg/g lipid weight of rough-toothed dolphin. Pentachlorobiphenyls, hexachlorobiphenyls and heptachlorobiphenyls were the predominant PCB congeners species. PCB153 was the most abundant congener in all samples. The PCB153/SigmaPCBs consistently comprised between 20% to 30% of all congeners. The toxicity measured as 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQs) were from 2.7 pg/g lipid weight of finless porpoise to 2,900 pg/g lipid weight of rough-toothed dolphin. PCB 118, a mono-ortho congener, was the largest contributor to TEQs. PCB concentrations and TEQs were higher in mature male than in immature male animals but were inconsistent in female animals because of a possible transferring of PCBs from maternal cetaceans to their offsprings during gestation and lactation. Stranded cetaceans had significantly higher PCB levels than by-catch cetaceans because of their higher lipid consumption during starvation or illness. From the collected samples, we also found that cetaceans from Taiwan waters had relatively lower PCB concentrations and TEQs than those from high-latitude areas.

  15. Formation and stability of polychlorinated biphenyl Pickering emulsions.

    PubMed

    Roy-Perreault, Andréanne; Kueper, Bernard H; Rawson, Jim

    2005-03-01

    An emulsion stabilized by colloidal suspensions of finely divided solids is known as a Pickering emulsion. The potential for polychlorinated biphenyls (PCBs) to form Pickering emulsions ex situ when in contact with powdered solids, such as clays and metal oxides, is investigated here. Bentonite, iron oxide and magnesium oxide dispersions proved to be robust Pickering emulsion stabilizers, whereas manganese oxide dispersions were not. Batch experiments revealed that emulsions can be formed using a moderately low energy input and can be stabilized with solid concentrations as low as 0.5 wt.%. For the base conditions (volumetric oil fraction (phi(oil))=30 vol.%; solid concentration (chi)=2 wt.%), the formed emulsions were indefinitely stable and the initial average droplet diameters varied from 80 to 258 mum, depending on the solid used in the colloidal dispersion. The average droplet size varied at early time, but for most conditions stabilized to a steady-state value 1 week after preparation. The effect of Ostwald ripening was limited. At greater than 0.5 wt.% concentration, the efficiency of the solid dispersion as a stabilizer was dependant on the volumetric oil fraction but not on the solid concentration. Generally, systems with volumetric oil fractions outside of the 20-70 vol.% range were unstable. The emulsions' droplet stability, average droplet size and size distribution were observed to vary as a function of the amount of energy provided to the system, the volumetric oil fraction, and the concentration of the solid in the aqueous dispersion. It is hypothesized that drilling through fractured rock in the immediate vicinity of dense, non-aqueous phase liquid (DNAPL) PCBs may provide both the energy and solid material necessary to form Pickering emulsions.

  16. Polychlorinated biphenyls in the atmosphere of southern Norway

    SciTech Connect

    Haugen, J.E. ); Wania, F. ); Lei, Y.D. . Dept. of Chemical Engineering and Applied Chemistry)

    1999-07-15

    Atmospheric concentrations of seven polychlorinated biphenyl (PCB) congeners (IUPAC No. 101, 105, 118, 138/163, 153, 156, 180) were measured every week from 1992 to 1995 in Lista, a coastal station in Southern Norway. This data set of 200 samples was analyzed with respect to the influence of time, temperature, air mass origin, and wind speed on both the absolute level and the relative congeneric composition of the PCBs. The geometric mean concentration of the sum of the seven PCB congeners was 114 pg[center dot]m[sup [minus]3], which is in the range observed at urban locations in Europe during the early 1990s. No obvious concentration decrease could be observed during the 4 years. PCB concentrations showed a clear seasonal fluctuation with higher levels during the summer. The temperature dependence of the air concentrations of individual congeners increased with the number of chlorine atoms per molecule resulting in an increase in the relative importance of the higher chlorinated congeners during warm periods. Air arriving in Southern Norway from southwesterly directions had slightly higher concentrations than air coming from the North, whereas the relative composition of the PCB congeners was not influenced by air mass origin. At higher wind speed the concentrations of PCBs decreased. Episodes of conspicuously elevated PCB concentrations neither were associated with a particular air mass origin nor had an unusual congeneric composition. The data analysis suggests that whereas regional air transport from central Europe contributes to the occurrence of PCBs in Lista, a large fraction of the PCBs stems likely from local sources.

  17. Dietary uptake of polychlorinated biphenyls (PCBs) by rainbow trout

    USGS Publications Warehouse

    Carline, Robert F.; Barry, Patrick M.; Ketola, H. George

    2004-01-01

    The presence of detectable levels of polychlorinated biphenyls (PCBs) in commercially produced fish feed has raised a concern about the degree of biomagnification of these contaminants in hatchery-reared trout. Our objectives were to (1) define the relationship between concentrations of PCBs in fish feed and in fish tissue and (2) estimate the relative contributions of feed and hatchery supply water to PCB concentrations in fish. We conducted a 6-month feeding trial with fingerling rainbow trout Oncorhynchus mykiss fed commercial diets with four concentrations of PCBs: a low-PCB diet (69 ng/g); a typical commercial diet (126 ng/g); and the typical diet spiked with PCBs at two levels (220 and 280 ng/g). The concentrations of PCBs in fillets after 1 month were commensurate with those in the feeds and remained relatively stable for the next 5 months; mean PCB concentrations in fillets ranged from 54 to 94 ng/g. Low levels of PCBs were detected in the hatchery supply water. We used the concentrations of PCBs in the feeds, absorption rates of PCBs, and two different rates of PCB depuration to estimate the potential uptake of PCBs from supply water. When we used a low depuration rate (half-life = 219 d), the computed body burdens of PCBs could be entirely attributed to the feeds. When a high depuration rate (half-life = 66 d) was used, some uptake of PCBs from the supply water was likely, but most of the total body burden originated from the feeds. We concluded that rainbow trout fed a diet with 126 ng/g PCBs would have a PCB concentration of about 60 ng/g in their fillets, which is high enough to warrant issuance of a consumption advisory (no more than one meal of fish per week) under a protocol adopted by some Great Lakes states.

  18. Ecotoxicology of polychlorinated biphenyls in fish--a critical review.

    PubMed

    Henry, T B

    2015-01-01

    Polychlorinated biphenyls (PCBs) are widespread persistent anthropogenic contaminants that can accumulate in tissues of fish. The toxicity of PCBs and their transformation products has been investigated for nearly 50 years, but there is a lack of consensus regarding the effects of these environmental contaminants on wild fish populations. The objective of this review is to critically examine these investigations and evaluate publicly available databases for evidence of effects of PCBs in wild fish. Biological activity of PCBs is limited to a small proportion of PCB congeners [e.g., dioxin-like PCBs (DL-PCBs)] and occurs at concentrations that are typically orders of magnitude higher than PCB levels detected in wild fish. Induction of biomarkers consistent with PCB exposure (e.g., induction of cytochrome P450 monooxygenase system) has been evaluated frequently and shown to be induced in fish from some environments, but there does not appear to be consistent reports of damage (i.e., biomarkers of effect) to biomolecules (i.e., oxidative injury) in these fish. Numerous investigations of endocrine system dysfunction or effects on other organ systems have been conducted in wild fish, but collectively there is no consistent evidence of PCB effects on these systems in wild fish. Early life stage toxicity of DL-PCBs does not appear to occur at concentrations reported in wild fish embryos, and results do not support an association between PCBs and decreased survival of early life stages of wild fish. Overall, there appears to be little evidence that PCBs have had any widespread effect on the health or survival of wild fish.

  19. Dechlorination of polychlorinated biphenyls by iron and its oxides.

    PubMed

    Sun, Yifei; Liu, Xiaoyuan; Kainuma, Masashi; Wang, Wei; Takaoka, Masaki; Takeda, Nobuo

    2015-10-01

    The decomposition efficiency of polychlorinated biphenyls (PCBs) was determined using elemental iron (Fe) and three iron (hydr)oxides, i.e., α-Fe2O3, Fe3O4, and α-FeOOH, as catalysts. The experiments were performed using four distinct PCB congeners (PCB-209, PCB-153, and the coplanar PCB-167 and PCB-77) at temperatures ranging from 180 °C to 380 °C and under an inert, oxidizing or reducing atmosphere composed of N2, N2+O2, or N2+H2. From these three options N2 showed to provide the best reaction atmosphere. Among the iron compounds tested, Fe3O4 showed the highest activity for decomposing PCBs. The decomposition efficiencies of PCB-209, PCB-167, PCB-153, and PCB-77 by Fe3O4 in an N2 atmosphere at 230 °C were 88.5%, 82.5%, 69.9%, and 66.4%, respectively. Other inorganic chlorine (Cl) products which were measured by the amount of inorganic Cl ions represented 82.5% and 76.1% of the reaction products, showing that ring cleavage of PCBs was the main elimination process. Moreover, the dechlorination did not require a particular hydrogen donor. We used X-ray photoelectron spectroscopy to analyze the elemental distribution at the catalyst's surface. The O/Fe ratio influenced upon the decomposition efficiency of PCBs: the lower this ratio, the higher the decomposition efficiency. X-ray absorption near edge structure spectra showed that α-Fe2O3 effectively worked as a catalyst, while Fe3O4 and α-FeOOH were consumed as reactants, as their final state is different from their initial state. Finally, a decomposition pathway was postulated in which the Cl atoms in ortho-positions were more difficult to eliminate than those in the para- or meta-positions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Transfer of polychlorinated biphenyls to infants from their mothers

    SciTech Connect

    Kodama, H.; Ota, H.

    1980-03-01

    Transfer of polychlorinated biphenyls (PCBs) which are environmental pollutants, to infants from their mothers was investigated from 1974 to 1977. The following samples were collected and analyzed for PCBs using a gas chromatographic determination: (a) maternal blood at 8 and 4 months prepartum, delivery, and 1, 3, 5, and 7 months postpartum; (b) cord blood at delivery; (c) human milk at 1, 3, 5, and 7 months postpartum; and (d) newborn infant blood at 3 months, 1, 2, and 3 yr after birth. The PCB levels in maternal blood gradually elevated with the progress of gestation and then decreased, reaching a general population level at 5 months postpartum. The PCB level in maternal blood at delivery was significantly higher than that in the cord blood. The mean values of PCB levels in human milk at 3 months postpartum-both the whole and fat basis-showed some differences in each sampling time period, however, those values were generally obtained within the normal range of ordinary Japanese lactating women. When the cord blood at delivery was considered as newborn infant blood at birth, the PCB levels in the blood of breast-fed infants rose markedly with ingestion of human milk, exceeding the level in the blood of their mothers at 3 months postpartum, and tended to increase until 1 yr of age, and then gradually decreased at 2 and 3 yr of age. However, the PCB levels in the blood of bottle-fed infants remained at a low concentration level during the same period. In this survey, the concentration of PCBs in the blood of two newborn infants who received their mothers' milk for a longer period of time than the other infants, continued to increase exponentially, finally reaching about a four-fold value of their mothers. These results suggest that the quantity of PCBs transferred to infants from their mothers via lactation was much greater than that transferred placentally.

  1. Association between polychlorinated biphenyls and Parkinson’s disease neuropathology

    PubMed Central

    Hatcher-Martin, Jaime M.; Gearing, Marla; Steenland, Kyle; Levey, Allan I.; Miller, Gary W.; Pennell, Kurt D.

    2012-01-01

    Polychlorinated biphenyls (PCBs) are synthetic chemicals primarily used as coolants and insulators in electrical equipment. Although banned for several decades, PCBs continue to exist in the environment because of their long half-life, continued presence in items produced before the ban, and poor disposal practices. Epidemiological and experimental studies have identified exposure to PCBs as a potential risk factor for Parkinson’s disease, perhaps more so in females. The objective of this work was to examine the association between PCB levels in post-mortem human brain tissue and the diagnosis of Parkinson’s disease, as well as the degree of nigral depigmentation. We also sought to determine if this association was more significant when patients were stratified by sex. Post-mortem brain samples from control patients and those diagnosed with Parkinson’s disease were obtained from the Emory University Brain Bank and from the Nun Study. Concentrations of eight prevalent PCB congeners were extracted from post-mortem brain tissue and analyzed using gas chromatography-mass spectrometry. PCB congeners 153 and 180 were significantly elevated in the brains of Parkinson’s disease patients. When stratified by sex, the female Parkinson’s disease group demonstrated significantly elevated concentrations of total PCBs and specifically congeners 138, 153, and 180 compared to controls, whereas PCB concentrations in males were not significantly different between control and Parkinson’s disease groups. In a separate population of women (Nun Study) who had no clinical signs or symptoms of PD, elevated concentrations total PCB and congeners 138, 153 and 180 were also observed in post-mortem brain tissue exhibiting moderate nigral depigmentation compared to subjects with mild or no depigmentation. These quantitative data demonstrate an association between brain PCB levels and Parkinson’s disease-related pathology. Furthermore, these data support epidemiological and

  2. Non–Dioxin-Like Polychlorinated Biphenyls and Risk of Endometriosis

    PubMed Central

    Trabert, Britton; De Roos, Anneclaire J.; Schwartz, Stephen M.; Peters, Ulrike; Scholes, Delia; Barr, Dana B.; Holt, Victoria L.

    2010-01-01

    Background Endometriosis, a gynecologic disorder affecting 8–10% of reproductive-age women in the United States, is defined as the presence of endometrial tissue outside the uterus and is linked to pelvic pain and infertility. Environmental contaminants, including polychlorinated biphenyls (PCBs), are hypothesized to contribute to endometriosis risk through effects on steroid hormones. Objective We evaluated serum concentrations of certain noncoplanar PCBs, which have no or only weak dioxin-like properties, as risk factors for endometriosis. Methods In a case–control study of Group Health enrollees in western Washington State, 20 PCB congeners were measured in serum from surgically confirmed endometriosis cases that were newly diagnosed between 1996 and 2001 (n = 251) and from female controls matched for age and reference year (n = 538). Results Summed and estrogenic PCB concentrations were not associated with endometriosis risk [summed: odds ratio (OR) = 1.3; 95% confidence interval (CI), 0.8–2.2; estrogenic: OR = 1.1; 95% CI, 0.8–1.4]. Although several congener-specific ORs were statistically above or below the null (PCB 170: third quartile vs. lowest: OR = 0.5; 95% CI, 0.3–0.9; PCB 196: third quartile vs. lowest: OR = 0.4; 95% CI, 0.2–0.7; PCB 201: second vs. lowest: OR = 0.5; 95% CI, 0.3–0.8; third quartile vs. lowest: OR = 0.4; 95% CI, 0.2–0.7), there were no overall consistent patterns of endometriosis risk. Conclusions Taken in context with other North American studies, our findings suggest that noncoplanar PCB concentrations consistent within the range of exposure currently observed in western Washington State do not contribute meaningfully to endometriosis risk. PMID:20423815

  3. 77 FR 12836 - Draft Toxicological Review of Biphenyl: In Support of Summary Information on the Integrated Risk...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-02

    ... Biphenyl: In Support of Summary Information on the Integrated Risk Information System (IRIS)'' (EPA/635/R... of Summary Information on the Integrated Risk Information System (IRIS)'' is available primarily via... AGENCY Draft Toxicological Review of Biphenyl: In Support of Summary Information on the Integrated...

  4. 76 FR 60827 - Draft Toxicological Review of Biphenyl: In Support of Summary Information on the Integrated Risk...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-30

    ... Biphenyl: In Support of Summary Information on the Integrated Risk Information System (IRIS)'' (EPA/ 635/R... Integrated Risk Information System (IRIS)'' is available primarily via the Internet on the NCEA home page... AGENCY Draft Toxicological Review of Biphenyl: In Support of Summary Information on the Integrated...

  5. Biphenyl derivatives incorporating urea unit as novel VEGFR-2 inhibitors: design, synthesis and biological evaluation.

    PubMed

    Wang, Chen; Gao, Hongping; Dong, Jinyun; Zhang, Yanmin; Su, Ping; Shi, Yaling; Zhang, Jie

    2014-01-01

    A series of novel biphenyl urea derivates were synthesized and investigated for their potential to inhibit vascular endothelial growth factor receptor-2 (VEGFR-2). In particular, A7, B3 and B4 displayed significant enzymatic inhibitory activities, with IC₅₀ values of 4.06, 4.55 and 5.26 nM. Compound A7 exhibited potent antiproliferative activity on several cell lines. SAR study suggested that the introduction of methyl at ortho-position of the biphenyl urea and tertiary amine moiety could improve VEGFR-2 inhibitory activity and antitumor effects. Molecular docking indicated that the urea moiety formed four hydrogen bonds with DFG residue. These biphenyl ureas could serve as promising lead compounds for further optimization.

  6. Occurrence, distribution, and dechlorination of polychlorinated biphenyls and health risk assessment in Selangor River basin.

    PubMed

    Sakai, Nobumitsu; Dayana, Emmy; Abu Bakar, Azizi; Yoneda, Minoru; Nik Sulaiman, Nik Meriam; Ali Mohd, Mustafa

    2016-10-01

    Polychlorinated biphenyls (PCBs) were monitored in surface water collected in the Selangor River basin, Malaysia, to identify the occurrence, distribution, and dechlorination process as well as to assess the potential adverse effects to the Malaysian population. Ten PCB homologs (i.e., mono-CBs to deca-CBs) were quantitated by using gas chromatography-mass spectrometry (GC/MS). The total concentration of PCBs in the 10 sampling sites ranged from limit of detection to 7.67 ng L(-1). The higher chlorinated biphenyls (tetra-CBs to deca-CBs) were almost not detected in most of the sampling sites, whereas lower chlorinated biphenyls (mono-CBs, di-CBs, and tri-CBs) dominated more than 90 % of the 10 homologs in all the sampling sites. Therefore, the PCB load was estimated to be negligible during the sampling period because PCBs have an extremely long half-life. The PCBs, particularly higher chlorinated biphenyls, could be thoroughly dechlorinated to mono-CBs to tri-CBs by microbial decomposition in sediment or could still be accumulated in the sediment. The lower chlorinated biphenyls, however, could be resuspended or desorbed from the sediment because they have faster desorption rates and higher solubility, compared to the higher chlorinated biphenyls. The health risk for the Malaysia population by PCB intake that was estimated from the local fish consumption (7.2 ng kg(-1) bw day(-1)) and tap water consumption (1.5 × 10(-3)-3.1 × 10(-3) ng kg(-1) bw day(-1)) based on the detected PCB levels in the surface water was considered to be minimal. The hazard quotient based on the tolerable daily intake (20 ng kg(-1) bw day(-1)) was estimated at 0.36.

  7. Concentration-dependent effects of carbon nanotubes on growth and biphenyl degradation of Dyella ginsengisoli LA-4.

    PubMed

    Qu, Yuanyuan; Wang, Jingwei; Zhou, Hao; Ma, Qiao; Zhang, Zhaojing; Li, Duanxing; Shen, Wenli; Zhou, Jiti

    2016-02-01

    To enrich the understanding on interactions between carbon nanotubes (CNTs) and microbes, the responses of a biphenyl-degrading bacterium to single-walled carbon nanotubes (SWCNTs), multi-walled carbon nanotubes (MWCNTs) and carboxyl single-walled carbon nanotubes (SWCNT-COOHs) were investigated. Electron microscopy, viability test, cellular membrane integrity, and oxidative stress analyses indicated that CNT toxicity was mainly caused by physical piercing. Apart from antibacterial activities, the experimental results showed that CNTs enhanced cell growth and biphenyl degradation at certain concentrations (1.0-1.5 mg/L). The CNTs aggregated and adsorbed cells and biphenyl to form a CNTs-cells-biphenyl coexisting system, thus it created a suitable microenvironment for cell attachment and proliferation where the cells could utilize biphenyl easier for their growth. To the best of our knowledge, this is the first report about CNTs' impact on biodegradation efficacy and growth of aromatic-degrading bacterium.

  8. Microsomal biphenyl hydroxylase of fall armyworm larvae and its induction by allelochemicals and host plants.

    PubMed

    Yu, S J; Ing, R T

    1984-01-01

    Biphenyl was hydroxylated to 4-hydroxybiphenyl by a mixed-function oxidase system from midgut microsomes of fall armyworm (Spodoptera frugiperda) larvae. Optimum conditions for assaying the enzyme were established. The microsomal biphenyl 4-hydroxylase activity increased during larval development and declined in the prepupa. Allelochemicals (monoterpenes, indoles and flavones), drugs (phenobarbital and 3-methylcholanthrene) and host plants were found to induce the hydroxylase. The enzyme was also found to be fairly active in other species such as velvetbean caterpillars, corn earworms, tobacco budworms, mole crickets, American cockroaches and honey bees.

  9. Design of antiviral stapled peptides containing a biphenyl cross-linker.

    PubMed

    Muppidi, Avinash; Zhang, Hongtao; Curreli, Francesca; Li, Nan; Debnath, Asim K; Lin, Qing

    2014-04-01

    Here we report the design and synthesis of a panel of stapled peptides containing a distance-matching biphenyl cross-linker based upon a peptide capsid assembly inhibitor reported previously. Compared with the linear peptide, the biphenyl-stapled peptides exhibited significantly enhanced cell penetration and potent antiviral activity in the cell-based infection assays. Isothermal titration calorimetry and surface plasmon resonance experiments revealed that the most active stapled CAI peptide binds to the C-terminal domain of HIV capsid protein as well as envelop glycoprotein gp120 with low micromolar binding affinities, and as a result, inhibits both the HIV-1 virus entry and the virus assembly.

  10. Bacterial degradation of polychlorinted biphenyls in sludge from an industrial sewer lagoon

    NASA Technical Reports Server (NTRS)

    Kim, W. S.; Takacs, A. M.; Kuivinen, D. E.

    1983-01-01

    A laboratory experiment was conducted to determine if polychlorinated biphenyls (PCB's) found in an industrial sewer sludge can be effectively degraded by mutant bacteria. The aerated sludge was inoculated daily with mutant bacteria in order to augment the existing bacteria with bacteria that were considered to be capable of degrading PCB's. The pH, nitrogen, and phosphorus levels were monitored daily to maintain an optimum growing medium for the bacteria. A gas chromatographic method was used to determine the PCB concentrations of the sludge initially and also throughout the experiment. Results and discussion of the bacterial treatment of polychlorinated biphenyls are presented.

  11. Bis(alkyl)thioethers on a biphenyl scaffold: A spectroscopic and structural insight

    NASA Astrophysics Data System (ADS)

    Ferguson, Rhiann; Nejman, Phillip S.; Slawin, Alexandra M. Z.; Woollins, J. Derek

    2017-09-01

    A series of bis(alkyl)thioether compounds utilising biphenyl as the backbone of the type 2,2‧-bis(alkylthio)-1,1‧-biphenyl have been prepared with yields of 32-70%. The six benzyl derivatives all displayed an AB quartet for the CH2 hydrogens within their 1H NMR spectra due to restricted rotation within the molecule. Where the alkyl group was changed to neopentyl the CH2 protons became equivalent giving rise to a singlet within the 1H NMR spectrum. The compounds have been characterised principally using multinuclear NMR spectroscopy and single crystal X-ray diffraction.

  12. Lactational transfer of mercury and polychlorinated biphenyls in polar bears.

    PubMed

    Knott, Katrina K; Boyd, Daryle; Ylitalo, Gina M; O'Hara, Todd M

    2012-07-01

    We examined concentrations of total mercury (tHg, inorganic and methylated forms) and polychlorinated biphenyls (PCBs) in blood and milk from free-ranging Southern Beaufort-Chukchi Sea polar bears (Ursus maritimus) to assess maternal transfer of contaminants during lactation and the potential health risk to nursing young. Concentrations of contaminants in the blood of dependent and juvenile animals (ages 1-5 years) ranged from 35.9 to 52.2 μg kg(-1) ww for tHg and 13.9 to 52.2 μg kg(-1) ww (3255.81-11067.79 μg kg(-1) lw) for ΣPCB(7)s, similar to those of adult females, but greater than adult males. Contaminant concentrations in milk ranged from 5.7 to 71.8 μg tHg kg(-1)ww and 160 to 690 μg ΣPCB(11)s kg(-1) ww (547-5190 μg kg(-1) lw). The daily intake levels for tHg by milk consumption estimated for dependent young were below the tolerable daily intake level (TDIL) of tHg established for adult humans. Although the daily intake levels of PCBs through milk consumption for cubs of the year exceeded the TDIL thresholds, calculated dioxin equivalents for PCBs in milk were below adverse physiological thresholds for aquatic mammals. Relatively high concentrations of non-dioxin like PCBs in polar bear milk and blood could impact endocrine function of Southern Beaufort-Chukchi Sea polar bears, but this is uncertain. Transfer of contaminants during mid to late lactation likely limits bioaccumulation of dietary contaminants in female polar bears during spring. As polar bears respond to changes in their arctic sea ice habitat, the adverse health impacts associated with nutritional stress may be exacerbated by tHg and PCBs exposure, especially in ecologically and toxicologically sensitive polar bear cohorts such as reproductive females and young. Copyright © 2012. Published by Elsevier Ltd.

  13. Plasma polychlorinated biphenyl concentrations and immune function in postmenopausal women

    SciTech Connect

    Spector, June T.; De Roos, Anneclaire J.; Ulrich, Cornelia M.; Sheppard, Lianne; Sjoedin, Andreas; Wener, Mark H.; Wood, Brent; and others

    2014-05-01

    Background: Polychlorinated biphenyl (PCB) exposure has been associated with non-Hodgkin lymphoma in several studies, and the immune system is a potential mediator. Objectives: We analyzed associations of plasma PCBs with immune function measures. We hypothesized that higher plasma PCB concentrations are associated with lower immune function cross-sectionally, and that increases in PCB concentrations over a one year period are associated with decreases in immune function. Methods: Plasma PCB concentrations and immune function [natural killer (NK) cell cytotoxicity and PHA-induced T-lymphocyte proliferation (PHA-TLP)] were measured at baseline and one year in 109 postmenopausal overweight women participating in an exercise intervention study in the Seattle, Washington (USA) area. Mixed models, with adjustment for body mass index and other potential confounders, were used to estimate associations of PCBs with immune function cross-sectionally and longitudinally. Results: Associations of PCBs with immune function measures differed across groups of PCBs (e.g., medium- and high-chlorinated and dioxin-like [mono-ortho-substituted]) and by the time frame for the comparison (cross-sectional vs. longitudinal). Higher concentrations of medium- and high-chlorinated PCBs were associated with higher PHA-TLP cross-sectionally but not longitudinally. The mean decrease in 0.5 µg/mL PHA-TLP/50.0 pmol/g-lipid increase in dioxin-like PCBs over one year was 51.6 (95% confidence interval 2.7, 100.5; P=0.039). There was no association between plasma PCBs and NK cytotoxicity. Conclusions: These results do not provide strong evidence of impaired cellular immunity from PCB exposure. Larger longitudinal studies with greater variability in PCB exposures are needed to further examine temporal associations of PCBs with immune function. - Highlights: • Plasma PCBs and immune function were measured in 109 women at baseline and one year. • Immune measures included T lymphocyte proliferation

  14. Polychlorinated biphenyls and organochlorine pesticides in plasma of older Canadians.

    PubMed

    Medehouenou, Thierry Comlan Marc; Ayotte, Pierre; Carmichael, Pierre-Hugues; Kröger, Edeltraut; Verreault, René; Lindsay, Joan; Dewailly, Éric; Tyas, Suzanne L; Bureau, Alexandre; Laurin, Danielle

    2011-11-01

    No nationwide study has ever measured polychlorinated biphenyl (PCB) and organochlorine pesticide (OCP) body burden in Canadians aged 65 years and over. The objective of this study was to determine plasma concentrations of PCB congeners and OCPs in participants from a sub-cohort of the Canadian Study of Health and Aging and to examine the effects of socio-demographic, anthropometric and lifestyle characteristics on selected organochlorine concentrations. Archived plasma samples collected from 2023 subjects were analyzed by gas chromatography-mass spectrometry using negative chemical ionization for 15 PCB congeners and 11 OCPs. Descriptive statistics were used to report PCB congeners and OCP plasma concentrations. Multivariate models were used to study whether age at blood collection, sex, education, body mass index, rural residence, geographic region, smoking status and alcohol intake influences PCB 153, the most abundant congener, and the major OCP (beta-hexachlorocyclohexane, hexachlorobenzene, trans-nonachlor, p,p'-DDE) plasma concentrations. Statistical analyses were restricted to 1979 subjects and 17 organochlorine compounds for which at least 50% of the samples had concentrations above the limit of detection. Of these, 775 were men (mean age: 82.2 years) and 1204 were women (mean age: 84.6 years). The median concentrations (ng/g lipid) of PCB 153 in the plasma of men and women were 70.9 and 75.4, respectively. The levels of the sum of PCBs and the sum of dioxin-like PCBs were 276 and 31.3 for men, and 300 and 45.5 for women, respectively. The median concentrations (ng/g lipid) of p,p'-DDE, the most abundant OCP, were 565 for men and 828 for women. All compounds were positively and significantly intercorrelated (rs=0.39-0.99; p<0.001). Except for trans-nonachlor, the multivariate models revealed that age and male sex were the determining characteristics that showed, respectively, strongly positive and negative associations with selected organochlorine

  15. Cancer mortality among electric utility workers exposed to polychlorinated biphenyls.

    PubMed Central

    Loomis, D; Browning, S R; Schenck, A P; Gregory, E; Savitz, D A

    1997-01-01

    OBJECTIVES: To assess whether excess mortality from cancer, malignant melanoma of the skin, and cancers of the brain and liver in particular, is associated with long term occupational exposure to polychlorinated biphenyls (PCBs). METHODS: An epidemiological study of mortality was conducted among 138,905 men employed for at least six months between 1950 and 1986 at five electrical power companies in the United States. Exposures were assessed by panels composed of workers, hygienists, and managers at each company, who considered tasks performed by workers in 28 job categories and estimated weekly exposures in hours for each job. Poisson regression was used to examine mortality in relation to exposure to electrical insulating fluids containing PCBs, controlling for demographic and occupational factors. RESULTS: Neither all cause nor total cancer mortality was related to cumulative exposure to PCB insulating fluids. Mortality from malignant melanoma increased with exposure; rate ratios (RRs) relative to unexposed men for melanoma were 1.23 (95% confidence interval (95% CI) 0.56 to 2.52), 1.71 (0.68 to 4.28) and 1.93 (0.52 to 7.14) for men with < 2000, > 2000-10,000, and > 10,000 hours of cumulative exposure to PCB insulating fluids, respectively, without consideration of latency. Lagging exposure by 20 years yielded RRs of 1.29 (0.76 to 2.18), 2.56 (1.09 to 5.97), and 4.81 (1.49 to 15.50) for the same exposure levels. Mortality from brain cancer was modestly increased among men with < 2000 hours (RR 1.61, 95% CI 0.86 to 3.01) and > 2000-10,000 hours exposure (RR 1.79, 95% CI 0.81 to 3.95), but there were no deaths from brain cancer among the most highly exposed men. A lag of five years yielded slightly increased RRs. Mortality from liver cancer was not associated with exposure to PCB insulating fluids. CONCLUSIONS: This study was larger and provided more detailed information on exposure than past investigations of workers exposed to PCBs. The results suggest that PCBs

  16. Polychlorinated biphenyls and their association with survival following breast cancer

    PubMed Central

    Parada, Humberto; Wolff, Mary S.; Engel, Lawrence S.; Eng, Sybil M.; Khankari, Nikhil K.; Neugut, Alfred I.; Teitelbaum, Susan L.; Gammon, Marilie D.

    2015-01-01

    Background Polychlorinated biphenyls (PCBs) are hypothesized to influence breast carcinogenesis due to their persistence and potential to induce estrogenic and anti-estrogenic effects. Whether PCBs influence survival following breast cancer is unknown. Methods A population-based cohort of women diagnosed with first primary invasive or in situ breast cancer in 1996–1997 and with blood-measured PCBs (n=627) collected shortly after diagnosis was followed for vital status through 2011. After 5 and 15 years we identified 54 and 187 deaths, respectively, of which 36 and 74 were breast cancer-related. Using Cox regression, we estimated hazard ratios (HR) and 95% confidence intervals (CI) for mortality for baseline PCB concentrations, individually and as estrogenic (ΣGroup 1B: PCB101, PCB174, PCB177, PCB187, PCB199), anti-estrogenic (ΣGroup 2A: PCB66, PCB74, PCB105, PCB118; Σ2B: PCB138, PCB170), and cytochrome P450 enzyme-inducing (ΣGroup 3: PCB99, PCB153, PCB180, PCB183, PCB203) groups. Results The highest PCB174 tertile was associated with an increase in all-cause (HR=2.22, 95%CI: 1.14–4.30) and breast cancer-specific (HR=3.15, 95%CI: 1.23–8.09) mortality within 5 years of diagnosis and remained associated with breast cancer-specific mortality (HR=1.88, 95%CI: 1.05–3.36) at 15 years. At 5 years, the highest tertile of PCB177 was positively associated with all-cause mortality (HR=2.12, 95%CI: 1.05–4.30). At 15 years, the highest tertiles of ΣGroup 2A congeners and PCB118 were inversely associated with all-cause mortality (HR=0.60, 95%CI: 0.39–0.83; HR=0.63, 95%CI: 0.43–0.92, respectively). Conclusions In this first US study of PCBs and breast cancer survival, PCBs were associated with mortality in biologically plausible directions. The investigation of other, structurally similar, chemicals may be warranted. PMID:26798968

  17. Evaluation of strains isolated by growth on naphthalene and biphenyl for hybridization of genes to dioxygenase probes and polychlorinated biphenyl-degrading ability.

    PubMed

    Pellizari, V H; Bezborodnikov, S; Quensen, J F; Tiedje, J M

    1996-06-01

    Approximately equal numbers of bacteria were isolated from primarily tropical soils by growth on biphenyl and naphthalene to compare their competence in polychlorinated biphenyl (PCB) degradation. The strains isolated by growth on biphenyl catalyzed more extensive PCB degradation than the strains isolated by growth on naphthalene, suggesting that naphthalene cocontamination may be only partially effective in stimulating the cometabolism of lower chlorinated PCBs. Probes were made from the bph, nah, and tod genes encoding the large iron iron sulfur protein of the dioxygenase complex and hybridized to 19 different strains. The hybridization patterns did not correlate well with the substrates of isolation, suggesting that there is considerable diversity in these genes in nature and that probe hybridization is not a reliable indication of catabolic capacity. The strains with the most extensive PCB degradation capacity did strongly hybridize to the bph probe, but a few strains that exhibited strong hybridization had poor PCB-degrading ability. Of the 19 strains studied, 5 hybridized to more than one probe and 2, including one strong PCB degrader, hybridized to all three probes. Southern blots showed that the bph and nah probes hybridized to separate bands, suggesting that multiple dioxygenases were present. Multiple dioxygenases may be an important feature of competitive decomposers in nature and hence may not be rare. Most of the isolates identified were members of the beta subgroup of the Proteobacteria, a few were gram positive, and none were true Pseudomonas species.

  18. Evaluation of strains isolated by growth on naphthalene and biphenyl for hybridization of genes to dioxygenase probes and polychlorinated biphenyl-degrading ability.

    PubMed Central

    Pellizari, V H; Bezborodnikov, S; Quensen, J F; Tiedje, J M

    1996-01-01

    Approximately equal numbers of bacteria were isolated from primarily tropical soils by growth on biphenyl and naphthalene to compare their competence in polychlorinated biphenyl (PCB) degradation. The strains isolated by growth on biphenyl catalyzed more extensive PCB degradation than the strains isolated by growth on naphthalene, suggesting that naphthalene cocontamination may be only partially effective in stimulating the cometabolism of lower chlorinated PCBs. Probes were made from the bph, nah, and tod genes encoding the large iron iron sulfur protein of the dioxygenase complex and hybridized to 19 different strains. The hybridization patterns did not correlate well with the substrates of isolation, suggesting that there is considerable diversity in these genes in nature and that probe hybridization is not a reliable indication of catabolic capacity. The strains with the most extensive PCB degradation capacity did strongly hybridize to the bph probe, but a few strains that exhibited strong hybridization had poor PCB-degrading ability. Of the 19 strains studied, 5 hybridized to more than one probe and 2, including one strong PCB degrader, hybridized to all three probes. Southern blots showed that the bph and nah probes hybridized to separate bands, suggesting that multiple dioxygenases were present. Multiple dioxygenases may be an important feature of competitive decomposers in nature and hence may not be rare. Most of the isolates identified were members of the beta subgroup of the Proteobacteria, a few were gram positive, and none were true Pseudomonas species. PMID:8787402

  19. EFFECTS OF DEVELOPMENTAL EXPOSURE TO THE POLYCHLORINATED BIPHENYL CONGENER 153 ON AUDITORY AND MOTOR FUNCTION.

    EPA Science Inventory

    Polychlorinated biphenyls (PCBs) are pervasive environmental contaminants that have been shown to detrimentally affect somatic and behavioral endpoints. In the present study, primiparous Long-Evans rats were exposed to 0, 1, 5, 20 or 60mg/kg/day PCB153 via oral gavage from Gesta...

  20. STUDIES ON ADSORPTION OF 2-CHLORO BIPHENYL ON SEDIMENTS AND SEDIMENT COMPONENTS

    EPA Science Inventory

    Polychlorinated biphenyls, or PCBs, are a family of 209 structurally related chemical compounds (congeners), consisting of two benzene rings and 1 to 10 chlorine atoms. They range from light, oily fluids to heavier, greasy or waxy substances. PCBs were discovered more than 100 ye...

  1. ENANTIOSELECTIVE REDUCTIVE TRANSFORMATION OF CHIRAL POLYCHLORINATED BIPHENYLS IN LAKE SEDIMENT MICROCOSMS

    EPA Science Inventory

    The transformation rates and enantiomeric ratios of two chiral poylchlorinated biphenyls (PCBs), 2,2',3,4',5',6-hexachlorobiphenyl (2,2',3,4',5',6-HCB) and 2,2',3,3',4,4',5,6-octachlorobiphenyl (2,2',3,3',4,4',5,6-OCB), were determined in anaerobic lake sediment microcosms (25oC)...

  2. Polybrominated biphenyls: Metabolism and toxicity. (Latest citations from the Life Sciences Collection database). Published Search

    SciTech Connect

    Not Available

    1993-05-01

    The bibliography contains citations concerning the adverse health effects resulting from polybrominated biphenyl (PBB) exposure, including liver and kidney function, neurological effects, and immune response. The biochemistry and mechanism of PBB toxicity in man and animals are examined. (Contains a minimum of 93 citations and includes a subject term index and title list.)

  3. MONITORING POLYCHLORINATED BIPHENYLS (PCBS) BIODEGRADATION USING CONTINUOUS-FLOW ISOTOPE RATIO MASS SPECTROMETRY

    EPA Science Inventory

    Research has shown that polychlorinated biphenyls (PCBs) in some cases can be removed from the environment by biodegradation. Aerobic and anaerobic biological processes have been determined in previous research to be capable of degrading PCBs. During the aerobic and anaerobic d...

  4. MONITORING POLYCHLORINATED BIPHENYLS (PCBS) BIODEGRADATION USING CONTINUOUS-FLOW ISOTOPE RATIO MASS SPECTROMETRY

    EPA Science Inventory

    Research has shown that polychlorinated biphenyls (PCBs) in some cases can be removed from the environment by biodegradation. Aerobic and anaerobic biological processes have been determined in previous research to be capable of degrading PCBs. During the aerobic and anaerobic d...

  5. Immunological disorders associated with polychlorinated biphenyls and related halogenated aromatic hydrocarbon compounds

    USGS Publications Warehouse

    Noguchi, G.E.; Leatherland, J.F.; Woo, P.T.K.

    1998-01-01

    This review characterizes immunological disorders in fish associated with the widespread environmental contaminants, polychlorinated biphenyls (PCBs), and related halogenated aromatic hydrocarbons (HAHs). Special attention is devoted to comparing the sensitivity of fish species, identifying sensitive immunological endpoints and postulating mechanisms of action.

  6. Treatment Of Polychlorinated Biphenyls In Two Surface Soils Using Catalyzed H2O2 Propagations

    EPA Science Inventory

    Two surface soils contaminated with polychlorinated biphenyls (PCBs) collected from Superfund sites in the New England region of the United States, Fletcher Paints and Merrimack Industrial Metals, were evaluated for field treatment at the bench level using catalyzed H2...

  7. STUDIES ON ADSORPTION OF 2-CHLORO BIPHENYL ON SEDIMENTS AND SEDIMENT COMPONENTS

    EPA Science Inventory

    Polychlorinated biphenyls, or PCBs, are a family of 209 structurally related chemical compounds (congeners), consisting of two benzene rings and 1 to 10 chlorine atoms. They range from light, oily fluids to heavier, greasy or waxy substances. PCBs were discovered more than 100 ye...

  8. CATALYTIC STEAM REFORMING OF CHLOROCARBONS: POLYCHLORINATED BIPHENYLS (PCBS). (R826694C633)

    EPA Science Inventory

    Experiments with commercial askarals (Aroclors 1221, 1248 and 1254) have confirmed the feasibility of catalytic steam reforming as a method for destroying polychlorinated biphenyls (PCBs). Rhodium, platinum and nickel supported on [Potential of viable but non-culturable bacteria in polychlorinated biphenyls degradation--a review].

    PubMed

    Su, Xiaomei; Ding, Linxian; Shen, Chaofeng

    2013-09-04

    The state of "viable but non-culturable" (VBNC) is a survival strategy adopted by microorganisms when exposed to environmental stress. With the increasingly serious problem of xenobiotics pollution, enhanced microbial processes that exploit the potential of microbes to remediate polychlorinated biphenyl-contaminated environments have been developed. Microorganisms represent a significant advance with respect to the transformation and degradation of polychlorinated biphenyls in the environment. It is of great importance to study the potential function of VBNC bacteria in polluted environment. In this paper, current research status of VBNC bacteria is summarized, and resuscitation of VBNC bacteria to potentially stimulate microbial degradation of pollutants is discussed in detail. Furthermore, we put forward a novel approach to explore the potential of VBNC bacteria for polychlorinated biphenyls degradation using resuscitation promoting factor (Rpf) of Micrococcus luteus. The novel efficient method is helpful for excavating and obtaining highly desirable polychlorinated biphenyls degrading microorganisms. Moreover, the prospect of VBNC bacteria to other environmental remediation fields, such as flocculation and nitrification deodorant, is addressed.

  9. Chlorinated biphenyl mineralization by individual populations and consortia of freshwater bacteria.

    PubMed Central

    Pettigrew, C A; Breen, A; Corcoran, C; Sayler, G S

    1990-01-01

    Comparative studies were performed to investigate the contribution of microbial consortia, individual microbial populations, and specific plasmids to chlorinated biphenyl biodegradation among microbial communities from a polychlorinated biphenyl-contaminated freshwater environment. A bacterial consortium, designated LPS10, was shown to mineralize 4-chlorobiphenyl (4CB) and dehalogenate 4,4'-dichlorobiphenyl. The LPS10 consortium involved three isolates: Pseudomonas testosteroni (LPS10A), which mediated the breakdown of 4CB and 4,4'-dichlorobiphenyl to 4-chlorobenzoic acid; an isolate tentatively identified as an Arthrobacter sp. (LPS10B), which mediated 4-chlorobenzoic acid degradation; and Pseudomonas putida bv. A (LPS10C), whose role in the consortium has not been determined. None of these isolates contained detectable plasmids or sequences homologous to the 4CB-degradative plasmid pSS50. A freshwater isolate, designated LBS1C1, was found to harbor a 41-megadalton plasmid that was related to the 35-megadalton plasmid pSS50, and this isolate was shown to mineralize 4CB. In chemostat enrichments with biphenyl and 4CB as primary carbon sources, the LPS10 consortium was found to outcomplete bacterial populations harboring plasmids homologous to pSS50. These results demonstrate that an understanding of the biodegradative capacity of individual bacterial populations as well as interacting populations of bacteria must be considered in order to gain a better understanding of polychlorinated biphenyl biodegradation in the environment. Images PMID:2117875

  10. Treatment Of Polychlorinated Biphenyls In Two Surface Soils Using Catalyzed H2O2 Propagations

    EPA Science Inventory

    Two surface soils contaminated with polychlorinated biphenyls (PCBs) collected from Superfund sites in the New England region of the United States, Fletcher Paints and Merrimack Industrial Metals, were evaluated for field treatment at the bench level using catalyzed H2...

  11. Effects of polychlorinated biphenyls (Aroclor 1242) on the ultrastructure of certain planktonic algae

    SciTech Connect

    Mahanty, H.K.; Fineran, B.A.; Gresshoff, P.M.

    1983-03-01

    Species of freshwater algae sensitive and resistant to polychlorinated biphenyls were examined by transmission electron microscopy after treatment. In all treated sensitive species, disruption of internal chloroplast membranes and failure of cytokinesis were the major changes observed. All control and resistant species showed well-preserved internal structures and regular cytokinesis.

  12. Commentary on Polychlorinated Biphenyls (PCBs), Toxins, and Neuropsychological Deficits: Good Science is the Antidote

    ERIC Educational Resources Information Center

    Hebben, Nancy

    2004-01-01

    The seven cohort studies of the relation between prenatal and postnatal exposure to polychlorinated biphenyls (PCBs) to cognitive, neuropsychological and behavioral development have suggested that exposure to PCBs can cause persistent changes in cognitive functioning. D.V. Cicchetti, A.S. Kaufman, and S.S. Sparrow (this issue) apply six scientific…

  13. Evaluating Health Risks from Inhaled Polychlorinated Biphenyls: Research Needs for Addressing Uncertainty

    EPA Science Inventory

    Indoor air polychlorinated biphenyl (PCB) concentrations in some U.S. schools are one or more orders of magnitude higher than background levels. In response to this, efforts have been made to assess the potential health risk posed by inhaled PCBs. These efforts are hindered by un...

  14. POLYCHLORINATED BIPHENYL MIXTURES (AROCLORS) INHIBIT LPS-INDUCED MURINE SPLENOCYTE PROLIFERATION IN VITRO. (R826687)

    EPA Science Inventory

    Abstract

    The immune system is believed to be a sensitive indicator for adverse polychlorinated biphenyl (PCB)-induced health effects. Four commercial PCB mixtures (Aroclors) or six individual PCB congeners were evaluated for their effect on splenocyte viability and lip...

  15. Determination of Polychlorinated Biphenyls in Soil and Sediment by Selective Pressurized Liquid Extraction with Immunochemical Detection

    EPA Science Inventory

    A selective liquid pressurized extraction (SPLE) method was developed as a streamlined sample preparation/cleanup procedure for determining Aroclors and coplanar polychlorinated biphenyls (PCBs) in soil and sediment matrices. The SPLE method was coupled with an enzyme-linked imm...

  16. Induction of monooxygenation in rainbow trout by polybrominated biphenyls: a comparative study.

    PubMed

    Elcombe, C R; Lech, J J

    1978-04-01

    Two commercial polychlorinated biphenyl mixtures (Aroclor 1254 and Aroclor 1242) and one polybrominated biphenyl mixture (FireMaster BP-6) were examined for their abilities to induce hepatic microsomal monooxygenation in rainbow trout (Salmo gairdneri). Pretreatment of rainbow trout with Aroclors 1254 and 1242 (150 mg/kg IP) resulted in an approximate 10-fold induction of arylhydrocarbon (benzo[a]pyrene) hydroxylation, ethoxycoumarin-O-deethylation and ethoxyresorufin-O-deethylation within 7 days after injection. These enzyme activities remained elevated above control values for at least 2-3 weeks. Administration of FireMaster BP-6 (150 mg/kg IP) also resulted in an induction of several monooxygenase activities. Arylhydrocarbon (benzo[a]pyrene) hydroxylation, ethoxycoumarin-O-deethylation and ethoxyresorufin-O-deethylation were increased by 6-, 3,- and 25-fold, respectively. Only the latter two activities remained elevated two weeks post-injection. Ethylmorphine-N-demethylation was unaffected by the polyhalogenated biphenyls. Significant increases in P-450 hemoprotein were not observed after pretreatment with any of the polyhalogenated biphenyls studied.

  17. Evaluating Health Risks from Inhaled Polychlorinated Biphenyls: Research Needs for Addressing Uncertainty

    EPA Science Inventory

    Indoor air polychlorinated biphenyl (PCB) concentrations in some U.S. schools are one or more orders of magnitude higher than background levels. In response to this, efforts have been made to assess the potential health risk posed by inhaled PCBs. These efforts are hindered by un...

  18. Plasma-chemical technology of treatment of halogen-containing waste including polychlorinated biphenyls

    NASA Astrophysics Data System (ADS)

    Gusarov, E. E.; Malkov, Yu. P.; Stepanov, S. G.; Troshchinenko, G. A.; Zasypkin, I. M.

    2010-12-01

    We consider the developed plasma-chemical technology of halogen-containing substances treatment. The paper contains the experimental plant schematic and the positive results obtained after the treatment of tetrafluoromethane, ozone-damaging freon 12, polychlorinated biphenyls (PCB), the waste containing fluoride and chloride organics. The technology is proposed for industrial application.

  19. POLYBROMINATED BIPHENYL EXPOSURE AND BENIGN BREAST DISEASE IN A COHORT OF US WOMEN. (R825300)

    EPA Science Inventory

    PURPOSE: We examined the relation between serum polybrominated biphenyl (PBB) levels and the risk of benign breast disease in a cohort of Michigan women unintentionally exposed to PBBs in 1973 and interviewed in 1997.

    METHODS: We used extend...

  1. Determination of Polychlorinated Biphenyls in Soil and Sediment by Selective Pressurized Liquid Extraction with Immunochemical Detection

    EPA Science Inventory

    A selective liquid pressurized extraction (SPLE) method was developed as a streamlined sample preparation/cleanup procedure for determining Aroclors and coplanar polychlorinated biphenyls (PCBs) in soil and sediment matrices. The SPLE method was coupled with an enzyme-linked imm...

  2. Polychlorinated Biphenyls (PCBs) in Fish Tissue in U.S. Fresh Waters

    EPA Science Inventory

    As of 2015 the U.S. EPA has conducted probabilistic, nationally-representative assessments of polychlorinated biphenyls (PCBs) in fish tissue in U.S. lakes (2000-2003), twice in rivers 5th order and greater (2008-2009 and 2013-2014) as part of National Rivers and Streams Assessme...

  3. ANALYSIS OF CHIRAL PESTICIDES AND POLYCHLORINATED BIPHENYL CONGENERS IN ENVIRONMENTAL SAMPLES

    EPA Science Inventory

    Over 25 % of pesticides and other toxic organic pollutants are chiral, as are 19 of the 209 polychlorinated biphenyl (PCB) congeners; that is, they exist as two mirror image species called enantiomers (PCB enantiomers are called atropisomers). The enantiomers of a chiral compound...

  4. ANALYSIS OF CHIRAL PESTICIDES AND POLYCHLORINATED BIPHENYL CONGENERS IN ENVIRONMENTAL SAMPLES

    EPA Science Inventory

    Over 25 % of pesticides and other toxic organic pollutants are chiral, as are 19 of the 209 polychlorinated biphenyl (PCB) congeners; that is, they exist as two mirror image species called enantiomers (PCB enantiomers are called atropisomers). The enantiomers of a chiral compound...

  5. Polychlorinated Biphenyls (PCBs) in Fish Tissue in U.S. Fresh Waters

    EPA Science Inventory

    As of 2015 the U.S. EPA has conducted probabilistic, nationally-representative assessments of polychlorinated biphenyls (PCBs) in fish tissue in U.S. lakes (2000-2003), twice in rivers 5th order and greater (2008-2009 and 2013-2014) as part of National Rivers and Streams Assessme...

  6. Commentary on Polychlorinated Biphenyls (PCBs), Toxins, and Neuropsychological Deficits: Good Science is the Antidote

    ERIC Educational Resources Information Center

    Hebben, Nancy

    2004-01-01

    The seven cohort studies of the relation between prenatal and postnatal exposure to polychlorinated biphenyls (PCBs) to cognitive, neuropsychological and behavioral development have suggested that exposure to PCBs can cause persistent changes in cognitive functioning. D.V. Cicchetti, A.S. Kaufman, and S.S. Sparrow (this issue) apply six scientific…

  7. ENANTIOMERIC COMPOSITION OF CHIRAL POLYCHLORINATED BIPHENYL ATROPISOMERS IN AQUATIC BED SEDIMENT

    EPA Science Inventory

    Enantiomeric ratios (ERs) for eight polychlorinated biphenyl (PCB) atropisomers were measured in aquatic sediment from selected sites throughout the United States by using chiral gas chromatography/mass spectrometry. Nonracemic ERs for PCBs 91, 95, 132, 136, 149, 174, and 176 wer...

  8. Chemometric comparison of polychlorinated biphenyl residues and toxicologically active polychlorinated biphenyl congeners in the eggs of Forster's Terns (Sterna fosteri)

    USGS Publications Warehouse

    Schwartz, Ted R.; Stalling, David L.

    1991-01-01

    The separation and characterization of complex mixtures of polychlorinated biphenyls (PCBs) is approached from the perspective of a problem in chemometrics. A technique for quantitative determination of PCB congeners is described as well as an enrichment technique designed to isolate only those congener residues which induce mixed aryl hydrocarbon hydroxylase enzyme activity. A congener-specific procedure is utilized for the determination of PCBs in whichn-alkyl trichloroacetates are used as retention index marker compounds. Retention indices are reproducible in the range of ±0.05 to ±0.7 depending on the specific congener. A laboratory data base system developed to aid in the editing and quantitation of data generated from capillary gas chromatography was employed to quantitate chromatographic data. Data base management was provided by computer programs written in VAX-DSM (Digital Standard MUMPS) for the VAX-DEC (Digital Equipment Corp.) family of computers.In the chemometric evaluation of these complex chromatographic profiles, data are viewed from a single analysis as a point in multi-dimensional space. Principal Components Analysis was used to obtain a representation of the data in a lower dimensional space. Two-and three-dimensional proections based on sample scores from the principal components models were used to visualize the behavior of Aroclor® mixtures. These models can be used to determine if new sample profiles may be represented by Aroclor profiles. Concentrations of individual congeners of a given chlorine substitution may be summed to form homologue concentration. However, the use of homologue concentrations in classification studies with environmental samples can lead to erroneous conclusions about sample similarity. Chemometric applications are discussed for evaluation of Aroclor mixture analysis and compositional description of environmental residues of PCBs in eggs of Forster's terns (Sterna fosteri) collected from colonies near Lake Poygan

  9. Metabolism of Doubly para-Substituted Hydroxychlorobiphenyls by Bacterial Biphenyl Dioxygenases

    PubMed Central

    Pham, Thi Thanh My; Sondossi, Mohammad

    2015-01-01

    In this work, we examined the profile of metabolites produced from the doubly para-substituted biphenyl analogs 4,4′-dihydroxybiphenyl, 4-hydroxy-4′-chlorobiphenyl, 3-hydroxy-4,4′-dichlorobiphenyl, and 3,3′-dihydroxy-4,4′-chlorobiphenyl by biphenyl-induced Pandoraea pnomenusa B356 and by its biphenyl dioxygenase (BPDO). 4-Hydroxy-4′-chlorobiphenyl was hydroxylated principally through a 2,3-dioxygenation of the hydroxylated ring to generate 2,3-dihydro-2,3,4-trihydroxy-4′-chlorobiphenyl and 3,4-dihydroxy-4′-chlorobiphenyl after the removal of water. The former was further oxidized by the biphenyl dioxygenase to produce ultimately 3,4,5-trihydroxy-4′-chlorobiphenyl, a dead-end metabolite. 3-Hydroxy-4,4′-dichlorobiphenyl was oxygenated on both rings. Hydroxylation of the nonhydroxylated ring generated 2,3,3′-trihydroxy-4′-chlorobiphenyl with concomitant dechlorination, and 2,3,3′-trihydroxy-4′-chlorobiphenyl was ultimately metabolized to 2-hydroxy-4-chlorobenzoate, but hydroxylation of the hydroxylated ring generated dead-end metabolites. 3,3′-Dihydroxy-4,4′-dichlorobiphenyl was principally metabolized through a 2,3-dioxygenation to generate 2,3-dihydro-2,3,3′-trihydroxy-4,4′-dichlorobiphenyl, which was ultimately converted to 3-hydroxy-4-chlorobenzoate. Similar metabolites were produced when the biphenyl dioxygenase of Burkholderia xenovorans LB400 was used to catalyze the reactions, except that for the three substrates used, the BPDO of LB400 was less efficient than that of B356, and unlike that of B356, it was unable to further oxidize the initial reaction products. Together the data show that BPDO oxidation of doubly para-substituted hydroxychlorobiphenyls may generate nonnegligible amounts of dead-end metabolites. Therefore, biphenyl dioxygenase could produce metabolites other than those expected, corresponding to dihydrodihydroxy metabolites from initial doubly para-substituted substrates. This finding shows that a clear

  10. Structural Basis of the Enhanced Pollutant-Degrading Capabilities of an Engineered Biphenyl Dioxygenase

    PubMed Central

    Dhindwal, Sonali; Gomez-Gil, Leticia; Neau, David B.; Pham, Thi Thanh My; Sylvestre, Michel; Eltis, Lindsay D.; Bolin, Jeffrey T.

    2016-01-01

    ABSTRACT Biphenyl dioxygenase, the first enzyme of the biphenyl catabolic pathway, is a major determinant of which polychlorinated biphenyl (PCB) congeners are metabolized by a given bacterial strain. Ongoing efforts aim to engineer BphAE, the oxygenase component of the enzyme, to efficiently transform a wider range of congeners. BphAEII9, a variant of BphAELB400 in which a seven-residue segment, 335TFNNIRI341, has been replaced by the corresponding segment of BphAEB356, 333GINTIRT339, transforms a broader range of PCB congeners than does either BphAELB400 or BphAEB356, including 2,6-dichlorobiphenyl, 3,3′-dichlorobiphenyl, 4,4′-dichlorobiphenyl, and 2,3,4′-trichlorobiphenyl. To understand the structural basis of the enhanced activity of BphAEII9, we have determined the three-dimensional structure of this variant in substrate-free and biphenyl-bound forms. Structural comparison with BphAELB400 reveals a flexible active-site mouth and a relaxed substrate binding pocket in BphAEII9 that allow it to bind different congeners and which could be responsible for the enzyme's altered specificity. Biochemical experiments revealed that BphAEII9 transformed 2,3,4′-trichlorobiphenyl and 2,2′,5,5′-tetrachlorobiphenyl more efficiently than did BphAELB400 and BphAEB356. BphAEII9 also transformed the insecticide dichlorodiphenyltrichloroethane (DDT) more efficiently than did either parental enzyme (apparent kcat/Km of 2.2 ± 0.5 mM−1 s−1, versus 0.9 ± 0.5 mM−1 s−1 for BphAEB356). Studies of docking of the enzymes with these three substrates provide insight into the structural basis of the different substrate selectivities and regiospecificities of the enzymes. IMPORTANCE Biphenyl dioxygenase is the first enzyme of the biphenyl degradation pathway that is involved in the degradation of polychlorinated biphenyls. Attempts have been made to identify the residues that influence the enzyme activity for the range of substrates among various species. In this study

  11. Development of field application vectors for bioremediation of soils contaminated with polychlorinated biphenyls.

    PubMed Central

    Lajoie, C A; Zylstra, G J; DeFlaun, M F; Strom, P F

    1993-01-01

    Field application vectors (FAVs), which are a combination of a selective substrate, a host, and a cloning vector, have been developed for the purpose of expressing foreign genes in nonsterile, competitive environments in which the gene products provide no advantage to the host. Such gene products are exemplified by the enzymes for the cometabolism of polychlorinated biphenyls (PCBs) through the biphenyl degradation pathway. Attempts to use highly competent PCB-cometabolizing strains in the environment in the absence of biphenyl have not been successful, while the addition of biphenyl is limited by its human toxicity and low water solubility. Broad-substrate-specificity PCB-degradative genes (bphABC) were cloned from a naturally occurring isolate. Pseudomonas sp. strain ENV307, into broad-host-range plasmid pRK293. The resulting PCB-degrading plasmids were transferred to the FAV host Pseudomonas paucimobilis 1IGP4, which utilizes the nontoxic, water-soluble, nonionic surfactant Igepal CO-720 as a selective growth substrate. Plasmid stability in the recombinant strains was determined in the absence of antibiotic selection. PCB-degrading activity was determined by resting cell assays. Treatment of contaminated soil (10, 100, or 1,000 ppm of Aroclor 1242) by surfactant amendment (1.0% [wt/wt]Igepal CO-720 in wet soil) and inoculation with recombinant isolates of strain 1IGP4 (approximately 4 x 10(6) cells per g of soil) resulted in degradation of many of the individual PCB congeners in the absence of biphenyl.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8328798

  12. Degradation of nonionic surfactants and polychlorinated biphenyls by recombinant field application vectors.

    PubMed

    Lajoie, C A; Layton, A C; Easter, J P; Menn, F M; Sayler, G S

    1997-10-01

    Degradation of polychlorinated biphenyls (PCBs) in the environment is limited by their aqueous solubility and the degradative competence of indigenous populations. Field application vectors (FAVs) have been developed in which surfactants are used to both increase the solubility of the PCBs and support the growth of surfactant-degrading strains engineered for PCB degradation. Surfactant and PCB degradation by two recombinant strains were investigated. Pseudomonas putida IPL5 utilizes both alkylethoxylate [polyoxyethylene 10 lauryl ether (POL)] and alkylphenolethoxylate [Igepal CO-720 (IGP)] surfactants as growth substrates, but only degrades the ethoxylate moiety. The resulting degradation products from the alkyl- and alkylphenolethoxylate surfactants were 2-(dodecyloxy)ethanol and nonylphenoldiethoxylates, respectively. Ralstonia eutropha B30P4 grows on alkylethoxylate surfactants without the appearance of solvent-extractable degradation products. It also degrades the 2-(dodecyloxy)ethanol produced by strain IPL5 from the alkylethoxylate surfactants. The extent of degradation of the alkylethoxylate surfactant (POL) was greater for strain IPL5 (90%) than for B30P4 (60%) as determined by the cobaltothiocyanate active substances method (CTAS). The recombinant strain B30P4::TnPCB grew on biphenyl. In contrast, the recombinant strain IPL5::TnPCB could not grow on biphenyl, and PCB degradation was inhibited in the presence of biphenyl. The most extensive surfactant and PCB degradation was achieved by the use of both recombinant strains together in the absence of biphenyl. PCB (Aroclor 1242) and surfactant (POL) concentrations were reduced from 25 ppm and 2000 ppm, respectively, to 6.5 ppm and 225 ppm, without the accumulation of surfactant degradation products. Given the inherent complexity of commercial surfactant preparations, the use of recombinant consortia to achieve extensive surfactant and PCB degradation appears to be an environmentally acceptable and effective

  13. Development of field application vectors for bioremediation of soils contaminated with polychlorinated biphenyls.

    PubMed

    Lajoie, C A; Zylstra, G J; DeFlaun, M F; Strom, P F

    1993-06-01

    Field application vectors (FAVs), which are a combination of a selective substrate, a host, and a cloning vector, have been developed for the purpose of expressing foreign genes in nonsterile, competitive environments in which the gene products provide no advantage to the host. Such gene products are exemplified by the enzymes for the cometabolism of polychlorinated biphenyls (PCBs) through the biphenyl degradation pathway. Attempts to use highly competent PCB-cometabolizing strains in the environment in the absence of biphenyl have not been successful, while the addition of biphenyl is limited by its human toxicity and low water solubility. Broad-substrate-specificity PCB-degradative genes (bphABC) were cloned from a naturally occurring isolate. Pseudomonas sp. strain ENV307, into broad-host-range plasmid pRK293. The resulting PCB-degrading plasmids were transferred to the FAV host Pseudomonas paucimobilis 1IGP4, which utilizes the nontoxic, water-soluble, nonionic surfactant Igepal CO-720 as a selective growth substrate. Plasmid stability in the recombinant strains was determined in the absence of antibiotic selection. PCB-degrading activity was determined by resting cell assays. Treatment of contaminated soil (10, 100, or 1,000 ppm of Aroclor 1242) by surfactant amendment (1.0% [wt/wt]Igepal CO-720 in wet soil) and inoculation with recombinant isolates of strain 1IGP4 (approximately 4 x 10(6) cells per g of soil) resulted in degradation of many of the individual PCB congeners in the absence of biphenyl.(ABSTRACT TRUNCATED AT 250 WORDS)

  14. Reductive debromination of the commercial polybrominated biphenyl mixture firemaster BP6 by anaerobic microorganisms from sediments.

    PubMed

    Morris, P J; Quensen, J F; Tiedje, J M; Boyd, S A

    1992-10-01

    Anaerobic microorganisms eluted from three sediments, one contaminated with polybrominated biphenyls (PBBs) and two contaminated with polychlorinated biphenyls, were compared for their ability to debrominate the commercial PBB mixture Firemaster. These microorganisms were incubated with reduced anaerobic mineral medium and noncontaminated sediment amended with Firemaster. Firemaster averages six bromines per biphenyl molecule; four of the bromines are substituted in the meta or para position. The inocula from all three sources were able to debrominate the meta and para positions. Microorganisms from the Pine River (St. Louis, Mich.) contaminated with Firemaster, the Hudson River (Hudson Falls, N.Y.) contaminated with Aroclor 1242, and Silver Lake (Pittsfield, Mass.) contaminated with Aroclor 1260 removed 32, 12, and 3% of the meta plus para bromines, respectively, after 32 weeks of incubation. This suggests that previous environmental exposure to PBBs enhances the debromination capability of the sediment microbial community through selection for different strains of microorganisms. The Pine River inoculum removed an average of 1.25 bromines per biphenyl molecule during a 32-week incubation period, resulting in a mixture potentially more accessible to aerobic degradation processes. No ortho bromine removal was observed. However, when Firemaster was incubated with Hudson River microorganisms that had been repeatedly transferred on a pyruvate medium amended with Aroclor 1242, 17% of the meta and para bromines were removed after 16 weeks of incubation and additional debromination products, including 2-bromobiphenyl and biphenyl, were detected. This suggests the possibility for ortho debromination, since all components of the Firemaster mixture have at least one ortho-substituted bromine.(ABSTRACT TRUNCATED AT 250 WORDS)

  15. Occurrence of Tn4371-related mobile elements and sequences in (chloro)biphenyl-degrading bacteria.

    PubMed

    Springael, D; Ryngaert, A; Merlin, C; Toussaint, A; Mergeay, M

    2001-01-01

    Tn4371, a 55-kb transposable element involved in the degradation and biphenyl or 4-chlorobiphenyl identified in Ralstonia eutropha A5, displays a modular structure including a phage-like integrase gene (int), a Pseudomonas-like (chloro)biphenyl catabolic gene cluster (bph), and RP4- and Ti-plasmid-like transfer genes (trb) (C. Merlin, D. Springael, and A. Toussaint, Plasmid 41:40-54, 1999). Southern blot hybridization was used to examine the presence of different regions of Tn4371 in a collection of (chloro)biphenyl-degrading bacteria originating from different habitats and belonging to different bacterial genera. Tn4371-related sequences were never detected on endogenous plasmids. Although the gene probes containing only bph sequences hybridized to genomic DNA from most strains tested, a limited selection of strains, all beta-proteobacteria, displayed hybridization patterns similar to the Tn4371 bph cluster. Homology between Tn4371 and DNA of two of those strains, originating from the same area as strain A5, extended outside the catabolic genes and covered the putative transfer region of Tn4371. On the other hand, none of the (chloro)biphenyl degraders hybridized with the outer left part of Tn4371 containing the int gene. The bph catabolic determinant of the two strains displaying homology to the Tn4371 transfer genes and a third strain isolated from the A5 area could be mobilized to a R. eutropha recipient, after insertion into an endogenous or introduced IncP1 plasmid. The mobilized DNA of those strains included all Tn4371 homologous sequences previously identified in their genome. Our observations show that the bph genes present on Tn4371 are highly conserved between different (chloro)biphenyl-degrading hosts, isolated globally but belonging mainly to the beta-proteobacteria. On the other hand, Tn4371-related mobile elements carrying bph genes are apparently only found in isolates from the environment that provided the Tn4371-bearing isolate A5.

  16. The occurrence and significance of polychlorinated biphenyls in the environment

    USGS Publications Warehouse

    Dustman, E.H.; Stickel, L.F.; Blus, L.J.; Reichel, W.L.; Wiemeyer, Stanley N.

    1971-01-01

    SUMMARY: Polychlorinated biphenyls constitute a group of chlorine-bearing compounds of industrial origin that have permeated the natural environment throughout the world. Their chemical structure resembles that of some of the organochlorine pesticides. They are troublesome interferences in gas chromatographic analysis of these pesticides. Although methods have been developed to overcome analytical problems, measurements of quantity still are only approximate. Special studies in the United States, Netherlands, and Great Britain have traced PCB's to industrial effluent, but other possible sources have not been followed. Their use in paints, cartons, and insulating fluids suggests that environmental pollution may be from many different sources. PCB's are present in fish and wildlife in many countries of the world. Quantities are higher in animals living near industrial areas. PCB's build up in biological food chains with increases of tens to thousands of times from lower to higher organisms. Experimental studies have shown that PCB's have a toxicity to mallards, pheasants, bobwhite quail, coturnix quail, red-winged blackbirds, starlings, cowbirds, and grackles that is of the same order as the toxicity of DDE to these species. Overt signs of poisoning also are similar to those caused by compounds of the DDT group. Toxic effects of DDE and Aroclor 1254 to coturnix chicks were additive, but not synergistic. PCB's containing higher percentages of chlorine are more toxic to birds than those containing lower percentages. PCB's of foreign manufacture contained contaminants to an extent that greatly increased their toxicity Aroclor 1242. Statistical evaluations of the role that different chemicals may play in thinning of eggshells of brown pelicans show that DDE residues correlate better with shell thinning than do residues of dieldrin or PCB's. Studies of the effects of PCB's in the environment are as yet insufficient for well-rounded conclusions. The evidence available

  17. Proof of concept for the use of macroinvertebrates as indicators of polychlorinated biphenyls (PCB) contamination in Lake Hartwell

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has been conducting research to develop methods and tools for the evaluation of monitored natural recovery (MNR) of sediments contaminated with polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and other lega...

  18. Evaluating Chemical Reactivity And Mechanical Stability Of Nano Palladized Iron Embedded In Activated Carbon On Dechlorination Of Polychlorinated Biphenyls

    EPA Science Inventory

    Remediation of contaminated sites with hydrophobic organic compounds such as polychlorinated biphenyls (PCBs) remains a scientific and technical challenge. The high stability, low aqueous solubility, and high organic affinity of PCBs make them difficult to treat. Many physical,...

  19. HIGH BREAST MILK LEVELS OF POLYCHLORINATEDE BIPHENYLS (PCBS) AMONG FOUR WOMEN LIVING ADJACENT TO A PCB-CONTAMINATED WASTE SITE

    EPA Science Inventory

    As a consequence of contamination by effluents from local electronics manufacturing facilities, the New Bedford Harbor and estuary in southeastern Massachusetts is among the sites in the United States that are considered the most highly contaminated by polychlorinated biphenyls (...

  20. ACCUMULATION OF THE PERSISTENT ENVIRONMENTAL TOXICANTS METHYLMERCURY OR POLYCHLORINATED BIPHENYLS IN IN VITRO MODELS OF RAT NEURONAL TISSUE.

    EPA Science Inventory

    Polychlorinated biphenyls (PCBs) and methylmercury (CH3Hg+) are known toxicants which persist in the environment and accumulate in tissue. Studies to identify mechanisms of action associated with these toxicants have largely been conducted in vitro, and dosimetry comparisons acro...

  1. Recombination of the bph (Biphenyl) Catabolic Genes from Plasmid pWW100 and Their Deletion during Growth on Benzoate

    PubMed Central

    Lloyd-Jones, Gareth; de Jong, Caroline; Ogden, Richard C.; Duetz, Wouter A.; Williams, Peter A.

    1994-01-01

    Pseudomonas sp. strain CB406 was isolated from polychlorinated biphenyl-contaminated soil and harbors a nontransmissible plasmid, pWW100, of approximately 200 kb which carries the genes required for biphenyl and 4-chlorobiphenyl catabolism. The catabolic phenotype was mobilized following the construction in vivo of a cointegrate plasmid containing functional upper and lower biphenyl operons inserted into the broad-host-range R plasmid RP4. The Bph+ phenotype carried by pWW100 was stable in nonselective media but was unstable during growth on benzoate, where the sequential selection of two species of bph deletion derivatives occurs at high frequency. This mirrors observations made with TOL plasmids (encoding toluene and xylene catabolism) grown under similar conditions. Subcloning of dioxygenase genes involved in biphenyl catabolism confirmed the localization of the bph genes on the wild-type plasmid and the RP4 cointegrate plasmid. Images PMID:16349195

  2. HEAVY METAL, ORGANOCHLORINE PESTICIDE AND POLYCHLORINATED BIPHENYL CONTAMINATION IN ARCTIC GROUND SQUIRRELS (SPERMOPHILUS PARRYI) IN NORTHERN ALASKA

    EPA Science Inventory

    Heavy metal and organochlorine (OC)concentrations, including organochlorine pesticides and polychlorinated biphenyl congeners (PCBs), were determined in arctic ground squirrels (Spermophilus parryi) from three sites in the Brooks Range of northern Alaska in 1991-93. Heavy metals ...

  3. ACCUMULATION OF THE PERSISTENT ENVIRONMENTAL TOXICANTS METHYLMERCURY OR POLYCHLORINATED BIPHENYLS IN IN VITRO MODELS OF RAT NEURONAL TISSUE.

    EPA Science Inventory

    Polychlorinated biphenyls (PCBs) and methylmercury (CH3Hg+) are known toxicants which persist in the environment and accumulate in tissue. Studies to identify mechanisms of action associated with these toxicants have largely been conducted in vitro, and dosimetry comparisons acro...

  4. On the enantioselective olefin epoxidation by doubly bridged biphenyl azepine derivatives--mixed tropos/atropos chiral biaryls.

    PubMed

    Vachon, Jérôme; Rentsch, Samuel; Martinez, Alexandre; Marsol, Claire; Lacour, Jérôme

    2007-02-07

    Diastereomeric doubly bridged biphenyl azepines, atropos at 20 degrees C and tropos at 80 degrees C, are precursors to effective iminium organocatalysts that are employed in the enantioselective epoxidation of prochiral olefins (up to 85% ee).

  5. HIGH BREAST MILK LEVELS OF POLYCHLORINATEDE BIPHENYLS (PCBS) AMONG FOUR WOMEN LIVING ADJACENT TO A PCB-CONTAMINATED WASTE SITE

    EPA Science Inventory

    As a consequence of contamination by effluents from local electronics manufacturing facilities, the New Bedford Harbor and estuary in southeastern Massachusetts is among the sites in the United States that are considered the most highly contaminated by polychlorinated biphenyls (...

  6. Evaluating Chemical Reactivity And Mechanical Stability Of Nano Palladized Iron Embedded In Activated Carbon On Dechlorination Of Polychlorinated Biphenyls

    EPA Science Inventory

    Remediation of contaminated sites with hydrophobic organic compounds such as polychlorinated biphenyls (PCBs) remains a scientific and technical challenge. The high stability, low aqueous solubility, and high organic affinity of PCBs make them difficult to treat. Many physical,...

  7. Proof of concept for the use of macroinvertebrates as indicators of polychlorinated biphenyls (PCB) contamination in Lake Hartwell

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has been conducting research to develop methods and tools for the evaluation of monitored natural recovery (MNR) of sediments contaminated with polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and other lega...

  8. Data on sediment quality and concentrations of polychlorinated biphenyls from the Lower Neponset River, Massachusetts, 2002-03

    USGS Publications Warehouse

    Breault, Robert F.; Cooke, Matthew G.; Merrill, Michael

    2004-01-01

    The U.S. Geological Survey, in cooperation with the Massachusetts Executive Office of Environmental Affairs Department of Fish and Game Riverways Program, and the U.S. Environmental Protection Agency, studied sediment and water quality in the lower Neponset River, which is a tributary to Boston Harbor. Grab and core samples of sediment were tested for elements and organic compounds including polyaromatic hydrocarbons, organochlorine pesticides, and polychlorinated biphenyls. Physical properties of sediment samples, including grain size, were also measured. Selected sediment-core samples were tested for reactive sulfides and metals by means of the toxicity characteristic leaching procedure, which are sediment-disposal-related tests. Water quality, with respect to polychlorinated biphenyl contamination, was determined by testing samples collected by PISCES passive-water-column samplers for polychlorinated biphenyl congeners. Total concentrations of polychlorinated biphenyls were calculated by congener and by Aroclor.

  9. HEAVY METAL, ORGANOCHLORINE PESTICIDE AND POLYCHLORINATED BIPHENYL CONTAMINATION IN ARCTIC GROUND SQUIRRELS (SPERMOPHILUS PARRYI) IN NORTHERN ALASKA

    EPA Science Inventory

    Heavy metal and organochlorine (OC)concentrations, including organochlorine pesticides and polychlorinated biphenyl congeners (PCBs), were determined in arctic ground squirrels (Spermophilus parryi) from three sites in the Brooks Range of northern Alaska in 1991-93. Heavy metals ...

  10. Asymmetric induction by the cholestanic moiety on tropos species: synthesis and stereochemical characterization of bile acid-based biphenyl phosphites.

    PubMed

    Iuliano, A; Facchetti, S; Uccello-Barretta, G

    2006-06-23

    Three different bile acid-derived biphenyl phosphites were synthesized, starting from cholic and deoxycholic acids and biphenol, and their stereochemical features were checked by CD and NMR spectroscopies. On the basis of the spectroscopic results, the capability of the cholestanic system to induce a prevalent sense of twist on the biphenyl moiety of the bile acid-derived phosphites as well as their tropos nature was inferred.

  11. Structurally simplified biphenyl combretastatin A4 derivatives retain in vitro anti-cancer activity dependent on mitotic arrest

    PubMed Central

    Tarade, Daniel; Ma, Dennis; Pignanelli, Christopher; Mansour, Fadi; Simard, Daniel; van den Berg, Sean; Gauld, James; McNulty, James; Pandey, Siyaram

    2017-01-01

    The cis-stilbene, combretastatin A4 (CA4), is a potent microtubule targeting and vascular damaging agent. Despite promising results at the pre-clinical level and extensive clinical evaluation, CA4 has yet to be approved for therapeutic use. One impediment to the development of CA4 is an inherent conformational instability about the ethylene linker, which joins two aromatic rings. We have previously published preliminary data regarding structurally simplified biphenyl derivatives of CA4, lacking an ethylene linker, which retain anti-proliferative and pro-apoptotic activity, albeit at higher doses. Our current study provides a more comprehensive evaluation regarding the anti-proliferative and pro-apoptotic properties of biphenyl CA4 derivatives in both 2D and 3D cancerous and non-cancerous cell models. Computational analysis has revealed that cytotoxicity of CA4 and biphenyl analogues correlates with predicted tubulin affinity. Additional mechanistic evaluation of the biphenyl derivatives found that their anti-cancer activity is dependent on prolonged mitotic arrest, in a similar manner to CA4. Lastly, we have shown that cancer cells deficient in the extrinsic pathway of apoptosis experience delayed cell death following treatment with CA4 or analogues. Biphenyl derivatives of CA4 represent structurally simplified analogues of CA4, which retain a similar mechanism of action. The biphenyl analogues warrant in vivo examination to evaluate their potential as vascular damaging agents. PMID:28253265

  12. Food contamination with polychlorinated biphenyls and dioxins in Belgium. Effects on the body burden.

    PubMed

    Van Larebeke, N; Covaci, A; Schepens, P; Hens, L

    2002-11-01

    The core paper of this debate shows that persistent organic pollutant residues of the 12 chemicals targeted for a phase out under the Stockholm Convention are present in almost all categories of food in the US food supply. For dioxins, the study does not use measured data, but is based upon potential dioxin residues in selected food items. Polychlorinated biphenyls are not included in the study. In this paper we discuss selected data of polychlorinated biphenyl and dioxin concentrations in Belgian food. Some of these exposures are chronic, others are attributable to incidents. Both result in high body burdens in Belgium. The paper also compares the current concentrations in food with the recent standards launched by the EU for dioxins in food, and discusses whether these values adequately protect European citizens.

  13. Ab initio studies of the optoelectronic properties of biphenyl derivatives in OLEDs

    NASA Astrophysics Data System (ADS)

    Hashemi, Hossein; Bregman, Avi; Jung, Jaehun; Kwon, Minsang; Kim, Jinsang; Kieffer, John; Kieffer Group Team; Kim Group Team

    The influence of molecular conformation on electron relaxation and photophysical properties of a series of biphenyl derivatives have been investigated using density functional theory (DFT) and time-dependent DFT(TDDFT). The calculated absorption and emission properties of the series as well as phosphorescence quantum yield are in good agreement with the available experimental data. The spin orbit coupling values and the S --> T intersystem-crossing matrix elements and crossing rate constants are also explored as a function of the twist angle between the rings. The T --> S0 radiative and non-radiative transition rates are calculated and discussed for each member of the series. In addition, the T --> S0 radiative transition rate constant is calculated for twisted biphenyls and compared to those for planar molecules. Acknowledge support from: National Science Foundation, Grant No. DMR-1435965.

  14. Assessment of exposure risk of polychlorinated biphenyls to interior least terns (Sterna antillarum).

    PubMed

    Sanchez, Brian C; Caldwell, Colleen A

    2008-03-01

    Risk of polychlorinated biphenyl (PCB) exposure and effects were assessed for a colony of federally endangered interior least terns (Sterna antillarum) nesting on the Bitter Lake National Wildlife Refuge (NM, USA). The colony feeds from an area on the Refuge (Hunter Marsh/Oxbow Complex) wherein fish with elevated concentrations of total PCBs have been documented. Concentrations of total PCBs in whole fish averaged 0.94 mg/kg with a maximum concentration of 2.77 mg/kg, wet weight. Estimated daily PCB intake rates by adult birds throughout their 180-d breeding season ranged from <0.01 mg/kg/d to 0.98 mg/ kg/d, yielding hazard quotients that ranged from 0.01 to 21.68. Polychlorinated biphenyls pose a moderate risk to the colony of interior least terns that breed at the Bitter Lake National Wildlife Refuge, but the exposure rate is not likely to threaten their overall breeding success.

  15. A practical approach to the degradation of polychlorinated biphenyls in transformer oil.

    PubMed

    Wu, Wenhai; Xu, Jie; Zhao, Hongmei; Zhang, Qing; Liao, Shijian

    2005-08-01

    A practical and efficient disposal method for hydrodechlorination of polychlorinated biphenyls (PCBs) in transformer oil is reported. Transformer oil containing PCBs was treated by nanometric sodium hydride (nano-NaH) and transition metal catalysts. High destruction and removal efficiency (89.8%) can be attained by nano-NaH alone under mild conditions. The process exhibits apparent characteristics of a first order reaction. The reductive ability of nano-NaH was enhanced by the addition of transition metal catalysts. In the presence of TiCl4, 99.9% PCBs was hydrodechlorinated. The complex reducing reagents, Ni(OAc)2+i-PrONa, show extra hydrodechlorinating activity for di-chlorinated biphenyls.

  16. Zero-valent iron-promoted dechlorination of polychlorinated biphenyls (PCBs)

    SciTech Connect

    Chuang, Fei-Wen; Larson, R.A.

    1995-12-01

    Zero-valent iron promoted the dechlorination of PCBs (Aroclors 1221 and 1254) at elevated temperatures in an oxygen-limited environment. At temperatures higher than 300{degrees}C, dechlorination of Aroclor 1221 began to occur; at 400{degrees}C, the major reaction product, biphenyl, was observed in highest yield. (At this temperature most of the PCBs were dechlorinated to biphenyl within 10 min.) At temperatures of 500{degrees}C or higher, dechlorination and other reactions of PCBs took place. At 600{degrees}C, almost all PCBs were destroyed by reactions other than hydrogenolytic dechlorination. Similar reactions were observed with the more highly chlorinated Aroclor 1254. Water or other impurities associated with the iron surface may donate protons or hydrogen atoms to the PCBs and take part in other reactions.

  17. (Biphenyl-2,2'-di-yl)di-tert-butyl-phos-phonium trifluoro-methane-sulfonate.

    PubMed

    Muller, Alfred; Holzapfel, Cedric W

    2013-01-01

    To aid in the elucidation of catalytic reaction mechanism of palladacycles, we found that reaction of trifluoro-methane-sulfonic acid with a phosphapalladacycle resulted in elimination of the palladium and formation of the title phospholium salt, C20H26P(+)·CF3SO3(-). Selected geometrical parameters include P-biphenyl (av.) = 1.801 (3) Å and P-t-Bu (av.) = 1.858 (3) Å, and significant distortion of the tetra-hedral P-atom environment with biphen-yl-P-biphenyl = 93.93 (13)° and t-Bu-P-t-Bu = 118.82 (14)°. In the crystal, weak C-H⋯O inter-actions lead to channels along the c axis that are occupied by CF3SO3(-) anions.

  18. Dechlorination of polychlorinated biphenyl-contaminated soil via anaerobic composting with pig manure.

    PubMed

    Zhang, Chi; Du, Yao; Tao, Xiao-Qing; Zhang, Kun; Shen, Dong-Sheng; Long, Yu-Yang

    2013-10-15

    Anaerobic dechlorination is an effective degradation pathway of higher chlorinated polychlorinated biphenyls (PCBs). The efficiency of anaerobic composting remediation of PCB-contaminated soil using pig manure was determined. The results show that the dechlorination of PCB-contaminated soil via anaerobic composting with pig manure is feasible. PCB concentration is the most critical factor. Elevated PCB concentrations can inhibit dechlorination but does not disrupt the anaerobic fermentation process. At 1 mg kg(-1) PCBs, the degradation rate of five or more chlorinated biphenyls is 43.8%. The highest dechlorination performance in this experiment was obtained when the soil-to-organic waste ratio, carbon-to-nitrogen ratio, moisture content, and PCB concentration were 2:3, 20, 60%, and 1 mg kg(-1), respectively.

  19. Modulating Inhibitors of Transthyretin Fibrillogenesis via Sulfation: Polychlorinated Biphenyl Sulfates as Models1

    PubMed Central

    Grimm, Fabian A.; Lehmler, Hans-Joachim; He, Xianran; Robertson, Larry W.; Duffel, Michael W.

    2015-01-01

    Small molecules that bind with high affinity to thyroxine (T4) binding sites on transthyretin (TTR) kinetically stabilize the protein’s tetrameric structure, thereby efficiently decreasing the rate of tetramer dissociation in TTR related amyloidoses. Current research efforts aim to optimize the amyloid inhibiting properties of known inhibitors, such as derivatives of biphenyls, dibenzofurans and benzooxazoles, by chemical modification. In order to test the hypothesis that sulfate group substituents can improve the efficiencies of such inhibitors, we evaluated the potential of six polychlorinated biphenyl sulfates to inhibit TTR amyloid fibril formation in vitro. In addition, we determined their binding orientations and molecular interactions within the T4 binding site by molecular docking simulations. Utilizing this combined experimental and computational approach, we demonstrated that sulfation significantly improves the amyloid inhibiting properties as compared to both parent and hydroxylated PCBs. Importantly, several PCB sulfates were of equal or higher potency than some of the most effective previously described inhibitors. PMID:25595224

  20. Biphenyls from Nicotiana tabacum and their anti-tobacco mosaic virus.

    PubMed

    Shang, Shan-Zhai; Xu, Wen-Xiu; Lei, Ping; Zhao, Wei; Tang, Jian-Guo; Miao, Ming-Ming; Sun, Han-Dong; Pu, Jian-Xin; Chen, Yong-Kuan; Yang, Guang-Yu

    2014-12-01

    Five new biphenyls, tababiphenyls A-E (1-5), together with five known ones (5-10), were isolated from the leaves of Nicotiana tabacum, of which compound 1 possessed a seldom reported 6-carbons unit in biphenyls. Their structures were established on the basis of extensive spectroscopic analyses. All compounds were tested for their anti-tobacco mosaic virus (anti-TMV) activities. The results showed that compounds 3 and 5 exhibited high anti-TMV activities with inhibition rate of 48.4% and 32.1%, respectively, which were higher than that of positive control (ningnanmycin). The other compounds also showed potential anti-TMV activities with inhibition rates in the range of 18.6-28.7%, respectively. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Permissivity of the biphenyl-specific aerobic bacterial metabolic pathway towards analogues with various steric requirements.

    PubMed

    Overwin, Heike; Standfuß-Gabisch, Christine; González, Myriam; Méndez, Valentina; Seeger, Michael; Reichelt, Joachim; Wray, Victor; Hofer, Bernd

    2015-09-01

    It has repeatedly been shown that aryl-hydroxylating dioxygenases do not possess a very high substrate specificity. To gain more insight into this phenomenon, we examined two powerful biphenyl dioxygenases, the well-known wild-type enzyme from Burkholderia xenovorans LB400 (BphA-LB400) and a hybrid enzyme, based on a dioxygenase from Pseudomonas sp. B4-Magdeburg (BphA-B4h), for their abilities to dioxygenate a selection of eight biphenyl analogues in which the second aromatic ring was replaced by aliphatic as well as aliphatic/aromatic moieties, reflecting a variety of steric requirements. Interestingly, both enzymes were able to catalyse transformation of almost all of these compounds. While the products formed were identical, major differences were observed in transformation rates. In most cases, BphA-B4h proved to be a significantly more powerful catalyst than BphA-LB400. NMR characterization of the reaction products showed that the metabolite obtained from biphenylene underwent angular dioxygenation, whereas all other compounds were subject to lateral dioxygenation at ortho and meta carbons. Subsequent growth studies revealed that both dioxygenase source strains were able to utilize several of the biphenyl analogues as sole sources of carbon and energy. Therefore, prototype BphBCD enzymes of the biphenyl degradative pathway were examined for their ability to further catabolize the lateral dioxygenation products. All of the ortho- and meta-hydroxylated compounds were converted to acids, showing that this pathway is quite permissive, enabling catalysis of the turnover of a fairly wide variety of metabolites.

  2. Altered biologic activities of commercial polychlorinated biphenyl mixtures after microbial reductive dechlorination.

    PubMed Central

    Mousa, M A; Ganey, P E; Quensen, J F; Madhukar, B V; Chou, K; Giesy, J P; Fischer, L J; Boyd, S A

    1998-01-01

    The reductive dechlorination of polychlorinated biphenyls (PCBs) by anaerobic bacteria has recently been established as an important environmental fate of these compounds. This process removes chlorines directly from the biphenyl ring with replacement by hydrogen, resulting in a product mixture in which the average number of chlorines per biphenyl is reduced. In this study, dechlorination of commercial PCB mixtures (Aroclors 1242 and 1254) by microorganisms eluted from PCB-contaminated sediments of the River Raisin (Michigan) and Silver Lake (Massachusetts) caused a depletion in the proportion of highly chlorinated PCB congeners and an accumulation of lesser-chlorinated congeners. Dechlorination occurred primarily at the meta and, to a much lesser extent, para positions of biphenyl. The concentrations of the coplanar congeners including 3,3',4,4',5-pentachlorobiphenyl, the most potent dioxinlike congener, were significantly lowered by reductive dechlorination. Microbial reductive dechlorination of commercial PCB mixtures caused a substantial reduction in biologic activities in several instances. It significantly lowered or eliminated the inhibitory effects of Aroclors on fertilization of mouse gametes in vitro. Similarly, the dechlorinated product mixtures had substantially lower ethoxyresorufin-O-deethylase induction potencies and showed less ability to induce activating protein 1 transcription factor activity as compared to the unaltered Aroclors. In other assays the same dechlorinated product mixtures demonstrated biologic activities similar to the nondechlorinated Aroclors, including the ability of PCB mixtures to stimulate insulin secretion and cause neutrophil activation. The data presented here establish that the biologic activities of commercial PCB mixtures are altered by microbial reductive dechlorination and that an assessment of their toxic potential requires an array of tests that include the different mechanisms associated with PCBs. Images Figure 2

  3. Semiquantitative determination of polychlorinated biphenyls in tissue samples by thin layer chromatography

    USGS Publications Warehouse

    Mulhern, B.M.; Cromartie, E.; Reichel, W.L.; Belisle, A.A.

    1971-01-01

    A method is described for the analysis of polychlorinated biphenyl (PCB) compounds in tissue samples. Cleanup by hexane-aceto-nitrile partitioning and Florisil column chromatography are performed on samples before oxidative treatment to convert DDE to DCBP. PCB components are then determined semi-quantitatively by TLC. No prior separation of PCB from chlorinated pesticides is required. The lower limit of sensitivity is 0.2 ?g.

  4. Polybrominated biphenyl exposure and human cancer: Report of a case and public health implications

    SciTech Connect

    Sherman, J.D.

    1991-05-01

    This is a human case report of documented exposure to polybrominated biphenyls (PBBs), with serial PBB determinations, obtained over an 11 year period, and signs and symptoms characteristic of PBB exposure, culminating in cancer. No epidemiological studies of PBB and cancer are available, but structure-activity relationships and animal studies were predictive of malignancy. The patient did not have the risk factors of alcoholism or cigarette smoking.

  5. Thermoplastic and thermoset main chain liquid crystal polymers prepared from biphenyl mesogen

    SciTech Connect

    Su, W.F.A.

    1993-12-31

    Main chain liquid crystal thermoplastic polyesters and thermosetting epoxy resins were prepared using biphenyl mesogen. The melting point of polyesters was effectively decreased by incorporating flexible methylene spacers into the polymer main chain. The liquid crystal epoxy resins exhibit high glass transition temperature, low thermal expansion coefficient, high dielectric strength and low dielectric loss. They are suitable for the preparation of self-reinforcing molecular composites.

  6. [Polymorphism of the bphA genes in bacteria destructing biphenyl/chlorinated biphenils].

    PubMed

    Shumkova, E S; Egorova, D O; Boronnikova, S V; Plotnikova, E G

    2015-01-01

    Polychlorinated biphenyls (PCBs) are persistent organic pollutants. Biphenyl 2,3-dioxygenase (BDO) is a key enzyme that determines the range of PCBs oxidized by a bacterial strain. BDO subunit α (BphA1) plays an essential role in substrate recognition and binding. The genes for dioxygenases that hydroxylate aromatic rings were screened and analyzed phylogenetically. Genes found in biphenyl-oxidizing Rhodococcus erythropolis strains G12a, B7b, and B106a proved to be similar to the published nucleotide sequences of the Rhodococcus sp. HA99 and R04 and Novosphingobium aromaticivorans F199 bphA1 genes, which code for the α-subunits that do not belong to the biphenyl/toluene dioxygenase (B/TDO) family. PCB-destructing R. ruber P25 was found to possess a unique bphA1 gene, which clusters together with the phenylpropionate dioxygenase (PPDO) α-subunits of Mycobacterium vanbaalenii PYR-1 and Frankia sp. EuI1c. The deduced amino acid sequences of the genes were analyzed. The amino acids of the BDO active site in R. wratislaviensis P1, P12, P13, and P20 (bphA1 genes of the B/TDO family) were identical to those of the active PCB degrader R. jostii RHA1. The Rhodococcus strains in question were shown to be active toward both orthoand parachlorinated ring of 2,4'-dichlorobiphenyl. The α-subunit amino acids responsible for the substrate specificity of the enzyme in Pseudomonas sp. S9, S13, S210, S211, and S212 (B/TDO family) were the same as in P. pseudoalcaligenes KF707. The Pseudomonas strains were active toward the para-chlorinated ring of 2,4'-dichlorobiphenyl. The results of screening bacterial strains for bphA1 can be used to identify the biotechnologically promising PCB destructors.

  7. CLOSURE REPORT FOR CORRECTIVE ACTION UNIT 528: POLYCHLORINATED BIPHENYLS CONTAMINATION NEVADA TEST SITE, NEVADA

    SciTech Connect

    BECHTEL NEVADA

    2006-09-01

    This Closure Report (CR) describes the closure activities performed at CAU 528, Polychlorinated Biphenyls Contamination, as presented in the Nevada Division of Environmental Protection (NDEP)-approved Corrective Action Plan (CAP) (US. Department of Energy, National Nuclear Security Administration Nevada Site Office [NNSAINSO], 2005). The approved closure alternative was closure in place with administrative controls. This CR provides a summary of the completed closure activities, documentation of waste disposal, and analytical data to confirm that the remediation goals were met.

  8. A new biphenyl derivative from the mangrove endophytic fungus Phomopsis longicolla HL-2232.

    PubMed

    Li, Xiao-Bao; Chen, Guang-Ying; Liu, Rui-Jie; Zheng, Cai-Juan; Song, Xin-Ming; Han, Chang-Ri

    2017-03-13

    A new biphenyl derivative 5,5'-dimethoxybiphenyl-2,2'-diol (1), together with five known compounds (2-5), was isolated from the mangrove endophytic fungus Phomopsis longicolla HL-2232. The structures of these compounds were elucidated using comprehensive spectroscopic methods. The absolute configuration of 4 was determined by single-crystal X-ray diffraction for the first time. The inhibitory activities of all compounds against two Vibrio bacteria were evaluated.

  9. Reductive dehalogenation of polybrominated and polychlorinated biphenyls by anaerobic microorganisms from sediment

    SciTech Connect

    Morris, P.J.

    1992-01-01

    Polychlorinated biphenyls (PCBs)and polybrominated biphenyls (PBBs) are stable industrial chemicals that consist of complex mixtures considered to be highly recalcitrant to biological degradation in the environment. Reductive dehalogenation is the only known biodegradation process for the more highly halogenated PCB and PBB mixtures. Studies were undertaken to: (1) examine in situ reductive debromination in sediments of the Pine River Reservoir, (2) compare the ability of microorganisms from PCB-contaminated and PBB-contaminated sediments to debrominate the commercial PBB mixture, Firemaster, (3) examine factors which might enhance reductive dehalogenation in sediments, (4) evaluate the role of sediment for dechlorinating microorganisms. Sediments in the heavily contaminated region of the Pine River have undergone little or no debromination. Anaerobic microorganisms previously shown to dechlorinate PCB mixtures were unable to dechlorinate Aroclor 1242 in the presence of Pine River sediments located close to the PBB manufacturing site. Microorganisms downstream of the heaviest contamination were able to debrominate Firemaster. Microorganisms from the Pine River (contaminated with Firemaster), Hudson River (contaminated with Aroclor 1242) and Silver Lake (contaminated with Aroclor 1260), removed 32%, 12%, and 3% of the meta plus para bromines, respectively, after 32 weeks. The Pine River inoculum removed an average of 1.25 bromines from the biphenyl molecule. When Firemaster was incubated with Hudson River microorganisms, 17% of the meta and para bromines were removed after 16 weeks, and additional debromination products, 2-bromobiphenyl and biphenyl, were detected suggesting ortho debromination. A PCB enrichment culture was established using pyruvate as an electron donor and Aroclor 1242 as the electron acceptor. Three Michigan surface soils, Pine River sediments, and ashed sediment supported reductive dechlorination of Aroclor 1242 by Hudson River microorganisms.

  10. 4-[(2'-Cyano-biphenyl-4-yl)methyl]-morpholin-4-ium nitrate.

    PubMed

    Sima, Weiwei

    2010-07-17

    The title ion pair, C(18)H(19)N(2)O(+)·NO(3) (-), features an N-H⋯O hydrogen bond linking the cation to the anion. The morpholine portion adopts a chair conformation; the aromatic rings of the biphenyl-ene portion are twisted [torsion angles for the four atoms involving the ar-yl-aryl bond = 35.1 (2)-40.4 (2)°].

  11. Contamination of the food chain by polychlorinated biphenyls from a broken transformer

    SciTech Connect

    Drotman, D.P.; Baxter, P.J.; Liddle, J.A.; Brokopp, C.D.; Skinner, M.D.

    1983-03-01

    In 1979, widespread distribution of chicken and egg food products and grease contaminated with polychlorinated biphenyl (PCBs) occurred across the United States and as far away as Canada and Japan. The contamination was traced to an accidental leakage of PCBs from a transformer stored in a hog slaughtering plant in Montana. Breast milk analyses showed the PCB absorption had occurred among egg consumers. The episode illustrates the need for heightened vigilance over the fate of PCBs still in use.

  12. Cometabolism of polychlorinated biphenyls: enhanced transformation of Aroclor 1254 by growing bacterial cells.

    PubMed Central

    Kohler, H P; Kohler-Staub, D; Focht, D D

    1988-01-01

    Acinetobacter sp. strain P6 and a soil isolate, Arthrobacter sp. strain B1B, were tested for their ability to transform Aroclor 1254 as washed resting cells and as growing cells with biphenyl as the substrate. Growing cells were far superior to resting-cell suspensions in terms of total polychlorinated biphenyl (PCB) transformation, transformation of specific PCB congeners, and diversity of congeners that were attacked. Growing cells of Acinetobacter sp. strain P6 and Arthrobacter sp. strain B1B transformed 32 and 23% of the [14C]Aroclor 1254, respectively, whereas resting cells of the same respective cultures transformed only 17 and 8%. Transformation was significantly greater with resting cells in only 2 of 39 cases in which congeners were transformed by both growing and resting cells of both cultures. The components of 19 and 12 capillary gas-chromatographic peaks of Aroclor 1254 were transformed by biphenyl-grown resting cells of Acinetobacter sp. strain P6 and Arthrobacter sp. strain B1B, respectively, whereas the components of an additional 6 and 7 peaks were attacked by growing cells of the same respective cultures. Biphenyl oxidation by resting cells of both cultures decreased with time to less than 8% in 28 h. In addition to the normal 2,3-dioxygenase attack on PCBs, Acinetobacter sp. strain P6 also attacked congeners lacking an open 2,3-position. The ability of Acinetobacter sp. strain P6 to transform the components of 25 of the 40 largest peaks of Aroclor 1254 makes it one of the most versatile PCB-transforming organisms yet reported. PMID:3140725

  13. Nano/bio treatment of polychlorinated biphenyls with evaluation of comparative toxicity

    DOE PAGES

    Le, Thao Thanh; Francis, Arokiasamy J.; Nguyen, Hoang Khanh; ...

    2015-02-03

    The persistence of polychlorinated biphenyl (PCB) Aroclor 1248 in soils and sediments is a major concern because of its toxicity and presence at high concentrations. In this study, we developed an integrated remediation system for PCBs using chemical catalysis and biodegradation. The dechlorination of Aroclor 1248 was achieved by treatment with bimetallic nanoparticles Pd/nFe under anoxic conditions. Among the 32 PCB congeners of Aroclor 1248 examined, our process dechlorinated 99%, 92%, 84%, and 28% of tri-, tetra-, penta-, and hexachlorinated biphenyls, respectively. The resulting biphenyl was biodegraded rapidly by Burkholderia xenovorans LB400. Benzoic acid was detected as an intermediate duringmore » the biodegradation process. The toxicity of the residual PCBs after nano-bio treatment was evaluated in terms of toxic equivalent values which decreased from 33.8 × 10-5 μg g-1 to 9.5 × 10-5 μg g-1. The residual PCBs also had low cytotoxicity toward Escherichia coli as demonstrated by lower reactive oxygen species levels, lower glutathione peroxidase activity, and a reduced number of dead bacteria.« less

  14. Nano/bio treatment of polychlorinated biphenyls with evaluation of comparative toxicity

    SciTech Connect

    Le, Thao Thanh; Francis, Arokiasamy J.; Nguyen, Hoang Khanh; Jeon, Jong -Rok; Chang, Yoon -Seok

    2015-02-03

    The persistence of polychlorinated biphenyl (PCB) Aroclor 1248 in soils and sediments is a major concern because of its toxicity and presence at high concentrations. In this study, we developed an integrated remediation system for PCBs using chemical catalysis and biodegradation. The dechlorination of Aroclor 1248 was achieved by treatment with bimetallic nanoparticles Pd/nFe under anoxic conditions. Among the 32 PCB congeners of Aroclor 1248 examined, our process dechlorinated 99%, 92%, 84%, and 28% of tri-, tetra-, penta-, and hexachlorinated biphenyls, respectively. The resulting biphenyl was biodegraded rapidly by Burkholderia xenovorans LB400. Benzoic acid was detected as an intermediate during the biodegradation process. The toxicity of the residual PCBs after nano-bio treatment was evaluated in terms of toxic equivalent values which decreased from 33.8 × 10-5 μg g-1 to 9.5 × 10-5 μg g-1. The residual PCBs also had low cytotoxicity toward Escherichia coli as demonstrated by lower reactive oxygen species levels, lower glutathione peroxidase activity, and a reduced number of dead bacteria.

  15. Nano/bio treatment of polychlorinated biphenyls with evaluation of comparative toxicity.

    PubMed

    Le, Thao Thanh; Nguyen, Khanh-Hoang; Jeon, Jong-Rok; Francis, Arokiasamy J; Chang, Yoon-Seok

    2015-04-28

    The persistence of polychlorinated biphenyl (PCB) Aroclor 1248 in soils and sediments is a major concern because of its toxicity and presence at high concentrations. In this study, we developed an integrated remediation system for PCBs using chemical catalysis and biodegradation. The dechlorination of Aroclor 1248 was achieved by treatment with bimetallic nanoparticles Pd/nFe under anoxic conditions. Among the 32 PCB congeners of Aroclor 1248 examined, our process dechlorinated 99%, 92%, 84%, and 28% of tri-, tetra-, penta-, and hexachlorinated biphenyls, respectively. The resulting biphenyl was biodegraded rapidly by Burkholderia xenovorans LB400. Benzoic acid was detected as an intermediate during the biodegradation process. The toxicity of the residual PCBs after nano-bio treatment was evaluated in terms of toxic equivalent values which decreased from 33.8×10(-5)μgg(-1) to 9.5×10(-5)μgg(-1). The residual PCBs also had low cytotoxicity toward Escherichia coli as demonstrated by lower reactive oxygen species levels, lower glutathione peroxidase activity, and a reduced number of dead bacteria. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Highly potent first examples of dual aromatase-steroid sulfatase inhibitors based on a biphenyl template.

    PubMed

    Woo, L W Lawrence; Jackson, Toby; Putey, Aurélien; Cozier, Gyles; Leonard, Philip; Acharya, K Ravi; Chander, Surinder K; Purohit, Atul; Reed, Michael J; Potter, Barry V L

    2010-03-11

    Single agents against multiple drug targets are of increasing interest. Hormone-dependent breast cancer (HDBC) may be more effectively treated by dual inhibition of aromatase and steroid sulfatase (STS). The aromatase inhibitory pharmacophore was thus introduced into a known biphenyl STS inhibitor to give a series of novel dual aromatase-sulfatase inhibitors (DASIs). Several compounds are good aromatase or STS inhibitors and DASI 20 (IC(50): aromatase, 2.0 nM; STS, 35 nM) and its chlorinated congener 23 (IC(50): aromatase, 0.5 nM; STS, 5.5 nM) are examples that show exceptional dual potency in JEG-3 cells. Both biphenyls share a para-sulfamate-containing ring B and a ring A, which contains a triazol-1-ylmethyl meta to the biphenyl bridge and para to a nitrile. At 1 mg/kg po, 20 and 23 reduced plasma estradiol levels strongly and inhibited liver STS activity potently in vivo. 23 is nonestrogenic and potently inhibits carbonic anhydrase II (IC(50) 86 nM). A complex was crystallized and its structure was solved by X-ray crystallography. This class of DASI should encourage further development toward multitargeted therapeutic intervention in HDBC.

  17. Cloning and expression in Escherichia coli of Pseudomonas strain LB400 genes encoding polychlorinated biphenyl degradation.

    PubMed Central

    Mondello, F J

    1989-01-01

    Pseudomonas strain LB400 is able to degrade an unusually wide variety of polychlorinated biphenyls (PCBs). A genomic library of LB400 was constructed by using the broad-host-range cosmid pMMB34 and introduced into Escherichia coli. Approximately 1,600 recombinant clones were tested, and 5 that expressed 2,3-dihydroxybiphenyl dioxygenase activity were found. This enzyme is encoded by the bphC gene of the 2,3-dioxygenase pathway for PCB-biphenyl metabolism. Two recombinant plasmids encoding the ability to transform PCBs to chlorobenzoic acids were identified, and one of these, pGEM410, was chosen for further study. The PCB-degrading genes (bphA, -B, -C, and -D) were localized by subcloning experiments to a 12.4-kilobase region of pGEM410. The ability of recombinant strains to degrade PCBs was compared with that of the wild type. In resting-cell assays, PCB degradation by E. coli strain FM4560 (containing a pGEM410 derivative) approached that of LB400 and was significantly greater than degradation by the original recombinant strain. High levels of PCB metabolism by FM4560 did not depend on the growth of the organism on biphenyl, as it did for PCB metabolism by LB400. When cells were grown with succinate as the carbon source, PCB degradation by FM4560 was markedly superior to that by LB400. Images PMID:2493454

  18. Degradation and total mineralization of monohalogenated biphenyls in natural sediment and mixed bacterial culture.

    PubMed Central

    Kong, H L; Sayler, G S

    1983-01-01

    Mixed bacterial cultures obtained from polychlorinated biphenyl-contaminated river sediments are capable of degrading monohalogenated biphenyls under simulated natural conditions. Culture conditions include river water as supportive medium and mixed bacterial cultures obtained from river sediments. Degradation occurs when the substrates are supplied as the sole carbon source or when added together with glucose. The degradation rates of 2-, 3-, and 4-chlorobiphenyl, at 30 micrograms ml-1, were 1.1, 1.6, and 2.0 micrograms ml-1 day-1, respectively. Monobrominated biphenyls, including 2-, 3-, and 4-bromobiphenyl, were degraded at rates of 2.3, 4.2, and 1.4 micrograms ml-1 day-1, respectively. Metabolites, including halogenated benzoates, were detected by high-performance liquid chromatography and mass spectrometry. By using chlorophenyl ring-labeled monochlorobiphenyls as substrates, total mineralization (defined as CO2 production from the chlorophenyl ring) was observed for 4-chlorobiphenyl but not for 2-chlorobiphenyl. Rates of total mineralization of 4-chlorobiphenyl (at 39 to 385 micrograms ml-1 levels) were dependent on substrate concentration, whereas variation of cell number in the range of 10(5) to 10(7) cells ml-1 had no significant effects. Simulated sunlight enhanced the rate of mineralization by ca. 400%. PMID:6639021

  19. A New Biphenyl Neolignan from Leaves of Patrinia villosa (Thunb.) Juss.

    PubMed Central

    Xin-Jia, Yan; Wei, Liu; Ying, Zhao; Ning, Chen; Ying, Xu; Jian, Wu; Tan, Wang; Yue, Li; Zheng, Xiang

    2016-01-01

    Results: One new stereoisomer of biphenylneolignan with four known compounds was isolated from the leaves of Patrinia villosa Juss. Methods: The structure of the new compound was elucidated as 2,6,2’,6’-tetramethoxy-4,4’-bis (1,2-trans-2,3-epoxy-1-hydroxypropyl) biphenyl (1) on the basis of spectroscopic analysis and comparison with literature data. The four known compounds were identified as 2,6,2’,6’-tetramethoxy-4,4’-bis(1,2-cis-2,3-epoxy-1-hydroxypropyl)biphenyl (2), 1H-indole-3-carbaldehyde (3), luteolin (4) and quercetin(5) by comparison of their spectral data with the reported data, respectively. Conclusions: Compound 1 is a new biphenylneolignan, compound 2 and 3 were isolated for the first time from the plant. SUMMARY One new stereoisomer of biphenylneolignan named 2,6,2’,6’-tetramethoxy-4,4’-bis (1,2-trans-2,3-epoxy-1-hydroxypropyl) biphenyl with four known compounds was isolated from the leaves of Patrinia villosa Juss. PMID:27019553

  20. Laboratory and human studies on polychlorinated biphenyls (PCBs) and related compounds.

    PubMed Central

    Kimbrough, R D

    1985-01-01

    Similar qualitative toxic effects have been observed in animals for a class of halogenated aromatic compounds, which include the halogenated biphenyls, naphthalenes, dibenzodioxins, and dibenzofurans. All of these compounds are lipid soluble and persist in the environment and in mammals. The polybrominated biphenyls (PBBs) are the most persistent. They are predominantly stored in fatty tissue; they pass the placenta and are excreted in milk. Some isomers of the halogenated biphenyls are more toxic than others. With some exceptions, the more toxic isomers are retained longer in tissues and are also the carcinogenic components of the mixture. Most of these chemicals seem to be promoters of carcinogenesis in animals rather than initiators. An array of toxic effects in laboratory animals has been ascribed to these compounds and numerous reviews summarizing this information are available. Less information is available on the human health effects of environmental and occupational exposure. Results of recent studies in animals to further elucidate the effects of these chemicals are presented, and results from some human studies conducted in the United States are reviewed. PMID:3921372

  1. Biphenyl metabolism by rat liver microsomes. Regioselective effects of inducers, inhibitors, and solvents

    SciTech Connect

    Haugen, D.A.

    1981-01-01

    The effects of the inducers phenobarbital and 3-methylcholanthrene, the inhibitors 7,8-benzoflavone and 1-benzyl-imidazole, and the solvents methanol, acetone, and dimethyl sulfoxide on the 2-, 3-, and 4-hydroxylation of biphenyl and the O-de-ethylation of 7-ethoxycoumarin by rat liver microsomes were examined. Phenobarbital pretreatment primarily induced 2- and 3-hydroxylation, the latter most dramatically. 3-Methylcholanthrene pretreatment induced 2- and 3-hydroxylation to similar extents. The inhibitors and solvents had regioselective effects on biphenyl metabolism that were characteristic of the uninduced, phenobarbital-induced, and 3-methylcholanthrene-induced microsomes. The presence of multiple forms of cytochrome P-450 in uninduced microsomes is indicated by the regioselective effects of the solvents and the inhibitors. The 3-methylcholanthrene-dependent increases in 2- and 3-hydroxylation appear due to induction of a single form of cytochrome P-450, as indicated by similar dose-response relationships and similar changes in sensitivitty to the inhibitors. The phenobarbital-dependent increases in 2- and 3-hydroxylation appear due to the induction of two forms of cytochrome P-450, as indicated by different changes in sensitivity to the effects of dimethyl sulfoxide and 7,8-benzoflavone. The results indicate that examination of the regioselectivity of biphenyl metabolism is a useful approach for characterizing microsomal mono-oxygenases, and they suggest that the approach may also be useful in the characterization of purified mono-oxygenase systems. (JMT)

  2. Polychlorinated biphenyls in eggs and chlorioallantoic membranes of American alligators (Alligator mississippiensis) from coastal South Carolina

    SciTech Connect

    Cobb, G.P.; Wood, P.D.; O`Quinn, M.

    1997-07-01

    Assessing chemical exposure in threatened or endangered wildlife species presents unique analytical problems. Chorioallantoic membranes (CAMs) have been proposed as surrogate tissues for evaluation of polychlorinated biphenyl (PCB) exposure in oviparous species. Research was undertaken to determine the extent of PCB accumulation in alligators (Alligator mississippiensis) at sites along the coast of South Carolina and to evaluate the utility of CAMs as surrogate tissues for determining PCB concentrations in whole alligator eggs. Polychlorinated biphenyls were found in eggs and CAMs of alligators from both sites examined. Concentrations of PCBs were higher in CAMs (p = 0.02) and eggs (p = 0.001) from sites known to contain chlorinated hydrocarbons than from more pristine sites. Total PCBs partitioned predictably (r{sup 2} > 0.59; p < 0.02) between egg and CAM tissues indicating the utility of CAMs to serve as surrogate tissues when comparing total PCB concentrations in whole eggs. Tetrachloro through octachloro biphenyl homologues and total PCBs in CAMs from reference areas were correlated with concentrations of these homologues in eggs. At contaminated sites, total PCB concentrations in CAMs were correlated with total PCB concentrations in eggs.

  3. Hydroxylated and methylsulfonyl polychlorinated biphenyl metabolites in albatrosses from Midway Atoll, North Pacific Ocean

    SciTech Connect

    Klasson-Wehler, E.; Bergman, A.; Athanasiadou, M.

    1998-08-01

    Concentrations of hydroxylated metabolites of polychlorinated biphenyls (PCBs) (OH-PCBs) and methylsulfonyl metabolites of PCBs (MeSO{sub 2}-PCBs) were determined in plasma and liver of albatrosses collected from the Midway Atoll in the central North Pacific Ocean. The mean total concentrations of OH-PCBs in plasma of Laysan albatrosses (Diomedea immutabilis) and black-footed albatrosses (Diomedea nigripes) were 11.5 and 27.1 ng/g wet weight, respectively. Total concentrations of OH-PCBs were only one- to fivefold less than those of total PCBs. 4-hydroxy-2,2{prime},3,4{prime},5,5{prime},6-heptachlorinated biphenyl and 4-hydroxy-2,2{prime},3,4{prime},5,5{prime}-hexachlorinated biphenyl were the predominant polychlorinated biphenylols, constituting 70 to 90% of the total OH-PCBs. Concentrations of MeSO{sub 2}-PCBs in liver were between 10.6 and 77 ng/g, lipid weight, approximately 250 times less than those of total PCBs. The MeSO{sub 2}-PCBs congeners retained in the liver were dominated by those having the methylsulfonyl group in the 3-position.

  4. Anaerobic degradation of polychlorinated biphenyls (PCBs) and polychlorinated biphenyls ethers (PBDEs), and microbial community dynamics of electronic waste-contaminated soil.

    PubMed

    Song, Mengke; Luo, Chunling; Li, Fangbai; Jiang, Longfei; Wang, Yan; Zhang, Dayi; Zhang, Gan

    2015-01-01

    Environmental contamination caused by electronic waste (e-waste) recycling is attracting increasing attention worldwide because of the threats posed to ecosystems and human safety. In the present study, we investigated the feasibility of in situ bioremediation of e-waste-contaminated soils. We found that, in the presence of lactate as an electron donor, higher halogenated congeners were converted to lower congeners via anaerobic halorespiration using ferrous ions in contaminated soil. The 16S rRNA gene sequences of terminal restriction fragments indicated that the three dominant strains were closely related to known dissimilatory iron-reducing bacteria (DIRB) and those able to perform dehalogenation upon respiration. The functional species performed the activities of ferrous oxidation to ferric ions and further ferrous reduction for dehalogenation. The present study links iron cycling to degradation of halogenated materials in natural e-waste-contaminated soil, and highlights the synergistic roles of soil bacteria and ferrous/ferric ion cycling in the dehalogenation of polychlorinated biphenyls (PCBs) and polybrominated biphenyl ethers (PBDEs).

  5. Sediment quality and polychlorinated biphenyls in the Lower Neponset River, Massachusetts, and implications for urban river restoration

    USGS Publications Warehouse

    Breault, Robert F.; Cooke, Matthew G.; Merrill, Michael

    2004-01-01

    Efforts to restore fish passage, habitat, and recreational use of the Neponset River, a tributary to Boston Harbor, Massachusetts, have raised concerns about the sediment, water, and biota quality of the river. Consequently, the U.S. Geological Survey, in cooperation with the Massachusetts Executive Office of Environmental Affairs Department of Fish and Game Riverways Program and the U.S. Environmental Protection Agency, studied sediment and water quality, with a specific focus on polychlorinated biphenyls, in the Neponset River. Sediment samples were collected throughout the Neponset River and tested for elements and organic compounds including polyaromatic hydrocarbons, organochlorine pesticides, and polychlorinated biphenyls. Although enriched compared to background concentrations, sediment quality in the Neponset River was generally better than that of other urban rivers in the United States, except with respect to one constituent, polychlorinated biphenyls. Concentrations of lead, some polyaromatic hydrocarbons, and polychlorinated biphenyls in the sediment may be toxic to aquatic organisms and may pose a risk to human health. The sediment quality also fails to meet the minimum requirements set by the Commonwealth of Massachusetts for lined landfill disposal. The locations of the source(s) of polychlorinated biphenyls to the Neponset River were determined by means of congener analysis from PISCES passive water-column samplers. The PISCES data indicate a sharp increase in polychlorinated biphenyl concentrations and a substantial shift in congener pattern downstream of one PISCES sampling location near Fairmont Avenue, Boston, Massachusetts. This result indicates that the area upstream of this sampling location may be the location of a historical source of polychlorinated biphenyls to the Neponset River. The present (2003) source to the water column may likely be PCB contaminated sediment.

  6. Optimizing Polychlorinated Biphenyl Degradation by Flavonoid-Induced Cells of the Rhizobacterium Rhodococcus erythropolis U23A.

    PubMed

    Pham, Thi Thanh My; Pino Rodriguez, Nancy Johanna; Hijri, Mohamed; Sylvestre, Michel

    2015-01-01

    There is evidence that many plant secondary metabolites may act as signal molecules to trigger the bacterial ability to metabolize polychlorinated biphenyls (PCBs) during the rhizoremediation process. However, the bases for the PCB rhizoremediation process are still largely unknown. The rhizobacterium Rhodococcus erythropolis U23A is unable to use flavanone as a growth substrate. However, on the basis of an assay that monitors the amount of 4-chlorobenzoate produced from 4-chlorobiphenyl by cells grown co-metabolically on flavanone plus sodium acetate, this flavonoid was previously found to be a potential inducer of the U23A biphenyl catabolic pathway. In this work, and using the same assay, we identified ten other flavonoids that did not support growth, but that acted as inducers of the U23A biphenyl pathway, and we confirmed flavonoid induction of the biphenyl catabolic pathway using quantitative real-time polymerase chain reaction (RT-qPCR) on the bphA gene. We also examined the effect of the growth co-substrate on flavonoid induction. Sodium acetate was replaced by glucose, mannose, sucrose, or mannitol, which are sugars found in plant root exudates. The data showed that the level of induction of strain U23A biphenyl-degrading enzymes was significantly influenced by the nature and concentration of the flavonoid in the growth medium, as well as by the substrate used for growth. Sucrose allowed for an optimal induction response for most flavonoids. Some flavonoids, such as flavone and isoflavone, were better inducers of the biphenyl catabolic enzymes than biphenyl itself. We also found that all flavonoids tested in this work were metabolized by strain U23A during co-metabolic growth, but that the metabolite profiles, as well as the level of efficiency of degradation, differed for each flavonoid. To obtain insight into how flavonoids interact with strain U23A to promote polychlorinated biphenyl (PCB) degradation, we determined the concentration of flavanone at

  7. Optimizing Polychlorinated Biphenyl Degradation by Flavonoid-Induced Cells of the Rhizobacterium Rhodococcus erythropolis U23A

    PubMed Central

    Hijri, Mohamed; Sylvestre, Michel

    2015-01-01

    There is evidence that many plant secondary metabolites may act as signal molecules to trigger the bacterial ability to metabolize polychlorinated biphenyls (PCBs) during the rhizoremediation process. However, the bases for the PCB rhizoremediation process are still largely unknown. The rhizobacterium Rhodococcus erythropolis U23A is unable to use flavanone as a growth substrate. However, on the basis of an assay that monitors the amount of 4-chlorobenzoate produced from 4-chlorobiphenyl by cells grown co-metabolically on flavanone plus sodium acetate, this flavonoid was previously found to be a potential inducer of the U23A biphenyl catabolic pathway. In this work, and using the same assay, we identified ten other flavonoids that did not support growth, but that acted as inducers of the U23A biphenyl pathway, and we confirmed flavonoid induction of the biphenyl catabolic pathway using quantitative real-time polymerase chain reaction (RT-qPCR) on the bphA gene. We also examined the effect of the growth co-substrate on flavonoid induction. Sodium acetate was replaced by glucose, mannose, sucrose, or mannitol, which are sugars found in plant root exudates. The data showed that the level of induction of strain U23A biphenyl-degrading enzymes was significantly influenced by the nature and concentration of the flavonoid in the growth medium, as well as by the substrate used for growth. Sucrose allowed for an optimal induction response for most flavonoids. Some flavonoids, such as flavone and isoflavone, were better inducers of the biphenyl catabolic enzymes than biphenyl itself. We also found that all flavonoids tested in this work were metabolized by strain U23A during co-metabolic growth, but that the metabolite profiles, as well as the level of efficiency of degradation, differed for each flavonoid. To obtain insight into how flavonoids interact with strain U23A to promote polychlorinated biphenyl (PCB) degradation, we determined the concentration of flavanone at

  8. Identification of a catabolic transposon, Tn4371, carrying biphenyl and 4-chlorobiphenyl degradation genes in Alcaligenes eutrophus A5.

    PubMed Central

    Springael, D; Kreps, S; Mergeay, M

    1993-01-01

    Alcaligenes eutrophus A5 catabolizes biphenyl to CO2 via benzoate and 4-chlorobiphenyl to 4-chlorobenzoate. In curing and conjugation experiments, the A5 endogenous 51-kb IncP1 plasmid pSS50 was found to be dispensable for biphenyl and 4-chlorobiphenyl catabolism. Transfer of the biphenyl- and 4-chlorobiphenyl-degrading phenotype by means of pSS50 was observed at a frequency of 10(-5) per transferred plasmid in matings of A5 with other A. eutrophus strains. Transconjugants harbor enlarged pSS50 derivatives which contain additional genetic information governing the oxidation of biphenyl and 4-chlorobiphenyl to benzoate and 4-chlorobenzoate and originating from the chromosome of strain A5. The following observations indicate that the catabolic genes reside on a 59-kb large transposon (Tn4371) for which a restriction map is presented. (i) Tn4371 transposes between different replicons and at different locations of the same replicon. (ii) Transposition was observed in a Rec- strain of A. eutrophus. (iii) Tn4371 transposes as a single, contiguous piece of DNA. Although an RP4::Tn4371 plasmid was stably maintained in different hosts, the plasmid conferred growth on biphenyl only when present in strains of A. eutrophus and in an Acinetobacter sp. strain. Images PMID:8383664

  9. Separation and enrichment of six indicator polychlorinated biphenyls from real waters using a novel magnetic multiwalled carbon nanotube composite absorbent.

    PubMed

    Zhang, Jiabin; Gan, Ning; Pan, Muyun; Lin, Saichai; Cao, Yuting; Wu, Dazhen; Long, Nengbing

    2015-03-01

    A novel and effective magnetic multiwalled carbon nanotube composite for the separation and enrichment of polychlorinated biphenyls was developed. Fe3 O4 @SiO2 core-shell structured nanoparticles were first synthesized, then the poly(sodium 4-styrenesulfonate) was laid on its surface to prepare the polyanionic magnetic nanoparticles. The above materials were then grafted with polycationic multiwalled carbon nanotubes, which were modified by polydiallyl dimethyl ammonium chloride through the layer-by-layer self-assembly approach. Its performance was tested by magnetic solid-phase extraction and gas chromatography with mass spectrometry for the determination of six kinds of indicator polychlorinated biphenyls in water samples. Under optimal conditions, the spiked recoveries of several real samples for six kinds of polychlorinated biphenyls (PCB28, PCB52, PCB101, PCB138, PCB153, PCB180) were in the range of 73.4-99.5% with relative standard deviations varying from 1.5 to 8.4%. All target compounds showed good linearities in the tested range with correlation coefficients higher than 0.9993. The limits of quantification for six kinds of indicator polychlorinated biphenyls were between 0.018 and 0.039 ng/mL. The proposed method was successfully applied to analyze polychlorinated biphenyls in real water samples. Satisfactory results were obtained using the effective magnetic absorbent.

  10. Polychlorinated biphenyl poisoning: correlation of sensory and motor nerve conduction, neurologic symptoms, and blood levels of polychlorinated biphenyls, quaterphenyls, and dibenzofurans

    SciTech Connect

    Chen, R.C.; Tang, S.Y.; Miyata, H.; Kashimoto, T.; Chang, Y.C.; Chang, K.J.; Tung, T.C.

    1985-08-01

    In 1979 in Taiwan, more than 2000 people were poisoned with rice cooking oil contaminated with polychlorinated biphenyls (PCB). One hundred ten patients were studied within one year of the exposure. The blood PCB levels were 39.3 +/- 16.6 ppb. The blood levels of the PCB derivatives, polychlorinated quaterphenyls (PCQ) and polychlorinated dibenzofurans (PCDF), were 8.6 +/- 4.8 and 0.076 +/- 0.038 ppb, respectively. Both the sensory and motor nerve conduction velocities (NCV) of the patients were significantly lower than the control. Abnormal slowing of sensory NCV was found in 43.6% and abnormal slowing of motor NCV was seen in 21.8%. Patients who had higher PCQ blood levels has significantly slower median nerve sensory NCV than those with lower PCQ levels. Patients with higher PCB blood levels had significantly slower peroneal nerve motor NCV than those with lower PCB levels.

  11. [Exposure to polychlorinated biphenyls (PCBs) in food and cancer risk: recent advances].

    PubMed

    Roveda, Anna Maria; Veronesi, Licia; Zoni, Roberta; Colucci, Maria Eugenia; Sansebastiano, Giuliano

    2006-01-01

    Polychlorinated Biphenyls are synthetic chlorinated hydrocarbon compounds whose commercial production started in the thirties and that have been widely used in the electro-technical industry. Although their production was stopped over 25 years ago, the Stockholm Convention included these compounds among the list of Persistent Organic Pollutants (POPs). In fact, humans continue to be exposed to the toxic effects of PCBs because of their resistance to chemical and biological decomposition, their capacity of bio-accumulation and their long half-life. Studies performed so far have pointed out a possible association between exposure to Polychlorinated Biphenyls and increased risk of developing some types of cancer (breast, prostate, testicular, ovarian and uterine cancers); it has also been suggested that these compounds may act as disruptive endocrine and cause infertility as well as other hormone-regulated disorders. PCBs accumulate in organisms through the food chain, and food is therefore the main exposure source for humans: it accounts for over 90% of exposure, the highest concentrations being found in fish (such as salmon and shellfish), dairy products (especially milk and butter) and animal fat. Moreover, waste-heaps, illegal disposal of oil waste and combustion of certain waste products in incineration plants represent sources of environmental pollution. The highest levels of PCBs in the environment were found in the early 1970s; since then concentrations of Polychlorinated Biphenyls have gradually decreased in all environmental components (water, air, earth and sediments), in fish, in other food products and lastly also in humans, thus suggesting that the associated risks have also likewise diminished.

  12. Transcriptomic Assessment of Isozymes in the Biphenyl Pathway of Rhodococcus sp. Strain RHA1†

    PubMed Central

    Gonçalves, Edmilson R.; Hara, Hirofumi; Miyazawa, Daisuke; Davies, Julian E.; Eltis, Lindsay D.; Mohn, William W.

    2006-01-01

    Rhodococcus sp. RHA1 grows on a broad range of aromatic compounds and vigorously degrades polychlorinated biphenyls (PCBs). Previous work identified RHA1 genes encoding multiple isozymes for most of the seven steps of the biphenyl (BPH) pathway, provided evidence for coexpression of some of these isozymes, and indicated the involvement of some of these enzymes in the degradation of BPH, ethylbenzene (ETB), and PCBs. To investigate the expression of these isozymes and better understand how they contribute to the robust degradative capacity of RHA1, we comprehensively analyzed the 9.7-Mb genome of RHA1 for BPH pathway genes and characterized the transcriptome of RHA1 growing on benzoate (BEN), BPH, and ETB. Sequence analyses revealed 54 potential BPH pathway genes, including 28 not previously reported. Transcriptomic analysis with a DNA microarray containing 70-mer probes for 8,213 RHA1 genes revealed a suite of 320 genes of diverse functions that were upregulated during growth both on BPH and on ETB, relative to growth on the control substrate, pyruvate. By contrast, only 65 genes were upregulated during growth on BEN. Quantitative PCR assays confirmed microarray results for selected genes and indicated that some of the catabolic genes were upregulated over 10,000-fold. Our analysis suggests that up to 22 enzymes, including 8 newly identified ones, may function in the BPH pathway of RHA1. The relative expression levels of catabolic genes did not differ for BPH and ETB, suggesting a common regulatory mechanism. This study delineated a suite of catabolic enzymes for biphenyl and alkyl-benzenes in RHA1, which is larger than previously recognized and which may serve as a model for catabolism in other environmentally important bacteria having large genomes. PMID:16957245

  13. Identification of Bacteria Utilizing Biphenyl, Benzoate, and Naphthalene in Long-Term Contaminated Soil

    PubMed Central

    Uhlik, Ondrej; Wald, Jiri; Strejcek, Michal; Musilova, Lucie; Ridl, Jakub; Hroudova, Miluse; Vlcek, Cestmir; Cardenas, Erick; Mackova, Martina; Macek, Tomas

    2012-01-01

    Bacteria were identified associated with biodegradation of aromatic pollutants biphenyl, benzoate, and naphthalene in a long-term polychlorinated biphenyl- and polyaromatic hydrocarbon-contaminated soil. In order to avoid biases of culture-based approaches, stable isotope probing was applied in combination with sequence analysis of 16 S rRNA gene pyrotags amplified from 13C-enriched DNA fractions. Special attention was paid to pyrosequencing data analysis in order to eliminate the errors caused by either generation of amplicons (random errors caused by DNA polymerase, formation of chimeric sequences) or sequencing itself. Therefore, sample DNA was amplified, sequenced, and analyzed along with the DNA of a mock community constructed out of 8 bacterial strains. This warranted that appropriate tools and parameters were chosen for sequence data processing. 13C-labeled metagenomes isolated after the incubation of soil samples with all three studied aromatics were largely dominated by Proteobacteria, namely sequences clustering with the genera Rhodanobacter Burkholderia, Pandoraea, Dyella as well as some Rudaea- and Skermanella-related ones. Pseudomonads were mostly labeled by 13C from naphthalene and benzoate. The results of this study show that many biphenyl/benzoate-assimilating bacteria derive carbon also from naphthalene, pointing out broader biodegradation abilities of some soil microbiota. The results also demonstrate that, in addition to traditionally isolated genera of degradative bacteria, yet-to-be cultured bacteria are important players in bioremediation. Overall, the study contributes to our understanding of biodegradation processes in contaminated soil. At the same time our results show the importance of sequencing and analyzing a mock community in order to more correctly process and analyze sequence data. PMID:22808223

  14. Enhancing and optimizing electronic transport in biphenyl derivative single-molecule junctions attached to carbon nanotubes electrodes

    NASA Astrophysics Data System (ADS)

    Reis-Silva, J. C.; Ferreira, D. F. S.; Leal, J. F. P.; Pinheiro, F. A.; Del Nero, J.

    2017-02-01

    We investigate, by means of ab initio calculations based on non-equilibrium Green's function method coupled to density function theory, electronic transport in molecular junctions composed of biphenyl (BP) and biphenyl within (-2H+) defect (BP2D) molecules attached to metallic (9,0) carbon nanotubes. We demonstrate that the BP2D junction exhibits unprecedented electronic transport properties, and that its conductance can be up to three orders of magnitude higher than biphenyl single-molecule junctions. These findings are explained in terms of the non-planar molecular conformation of BP2D, and of the stronger electronic coupling between the BP2D molecule and the organic electrodes, which confers high stability to the junction. Our results suggest that BP2D attached to carbon nanotubes can be explored as an efficient and highly stable platform in single-molecule electronics with extraordinary transport properties.

  15. Assessment of polychlorinated biphenyls and mercury levels in soil and biological samples from San Felipe, Nuevo Mercurio, Zacatecas, Mexico.

    PubMed

    Costilla-Salazar, Rogelio; Trejo-Acevedo, Antonio; Rocha-Amador, Diana; Gaspar-Ramírez, Octavio; Díaz-Barriga, Fernando; Pérez-Maldonado, Iván Nelinho

    2011-02-01

    The aim of this work was to evaluate contamination by polychlorinated biphenyls and mercury in soil, and to assess exposure level to both contaminants in children living in San Felipe, Nuevo Mercurio, Zacatecas, Mexico. We found soil levels of total polychlorinated biphenyls ranging from non detectable (nd) to 190 μg/kg. Mercury soil levels ranged from 8.9 to 10215.0 mg/kg. Exposure levels of total polychlorinated biphenyls assessed in blood and urinary mercury in children living in the studied community were 1,600 ± 8,800 ng/g lipid and 4.2 ± 7.1 μg/g creatinine, respectively.

  16. Electronic transport in biphenyl single-molecule junctions with carbon nanotubes electrodes: The role of molecular conformation and chirality

    SciTech Connect

    Brito Silva, C. A. Jr.; Granhen, E. R.; Silva, S. J. S. da; Leal, J. F. P.; Del Nero, J.; Pinheiro, F. A.

    2010-08-15

    We investigate, by means of ab initio calculations, electronic transport in molecular junctions composed of a biphenyl molecule attached to metallic carbon nanotubes. We find that the conductance is proportional to cos{sup 2} {theta}, with {theta} the angle between phenyl rings, when the Fermi level of the contacts lies within the frontier molecular orbitals energy gap. This result, which agrees with experiments in biphenyl junctions with nonorganic contacts, suggests that the cos{sup 2} {theta} law has a more general applicability, irrespective of the nature of the electrodes. We calculate the geometrical degree of chirality of the junction, which only depends on the atomic positions, and demonstrate that it is not only proportional to cos{sup 2} {theta} but also is strongly correlated with the current through the system. These results indicate that molecular conformation plays the preponderant role in determining transport properties of biphenyl-carbon nanotubes molecular junctions.

  17. Polychlorinated biphenyls-containing electrical insulating oil contaminated soil treatment with calcium and magnesium peroxides.

    PubMed

    Goi, Anna; Viisimaa, Marika; Trapido, Marina; Munter, Rein

    2011-02-01

    Calcium and magnesium peroxides were applied for the treatment of soil contaminated by polychlorinated biphenyls-containing electrical insulating oil (Aroclor 1016). The removal of PCB-containing electrical insulating oil was achieved with the addition of either calcium peroxide or magnesium peroxide alone and dependent on dosages of the chemical. A 21-d treatment of 60% watered soil with the moderate addition (chemical/oil weight ratio of 0.005/1) of either calcium peroxide or magnesium peroxide resulted in nearly complete (96 ± 2%) oil removal, unsubstantial increase in soil pH and almost no changes in oxygen consumption and dehydrogenase activity, making it suitable for the soil decontamination.

  18. Laboratory data base for isomer-specific determination of polychlorinated biphenyls

    SciTech Connect

    Schwartz, T.R.; Campbell, R.D.; Stalling, D.L.; Little, R.L.; Petty, J.D.; Hogan, J.W.; Kaiser, E.M.

    1984-07-01

    A computer-assisted technique for quantitative determination of polychlorinated biphenyl isomers is described. PCB isomers were identified by use of a retention index system with n-alkyl trichloroacetates as retention index marker compounds. A laboratory data base system was developed to aid in editing and quantitation of data generated from capillary gas chromatographic data. Data base management was provided by computer programs written in DSM-11 (Digital Standard MUMPS) for the PDP-11 family of computers. 13 references, 4 figures, 2 tables.

  19. Polychlorinated biphenyls in plant foliage: translocation or volatilization from contaminated soils

    SciTech Connect

    Bacci, E.; Gaggi, C.

    1985-11-01

    Physical properties such as water solubility, vapor pressure, and Henry's law constant suggest that polychlorinated biphenyls (PCB's) can easily reach the troposphere as vapor. The potential of plant foliar tissues to take up PCB's as vapor has probably been underrated in some of the previous works. Nevertheless recently it was reported that the level of PCB's found in the foliage is mainly due to vapor transport from the soil, rather than to translocation through the plant. This research has been planned to assess the influence of translocation on the concentration of PCB's in the foliage of different plant species.

  20. Heavy metal, polychlorinated biphenyl and organochlorine pesticide residues in marine organisms: risk evaluation for consumers.

    PubMed

    Marcotrigiano, G O; Storelli, M M

    2003-09-01

    This survey provides information on the levels of heavy metal, polychlorinated biphenyl and organochlorine pesticide residues in marine organisms to ascertain whether these concentrations exceeded the prescribed legal limits. In order to assess the potential human health impact, the weekly intake was estimated. Most of the organisms analysed showed higher levels of mercury than the maximum permissible limit, while cadmium and lead were below the proposed permissible limits in all samples. The estimated intake was far above the established Provisional Tolerable Weekly Intake for all metals, except for total mercury.

  1. Whole-Cell Fluorescent Biosensors for Bioavailability and Biodegradation of Polychlorinated Biphenyls

    PubMed Central

    Liu, Xuemei; Germaine, Kieran J.; Ryan, David; Dowling, David N.

    2010-01-01

    Whole-cell microbial biosensors are one of the newest molecular tools used in environmental monitoring. Such biosensors are constructed through fusing a reporter gene such as lux, gfp or lacZ, to a responsive promoter. There have been many reports of the applications of biosensors, particularly their use in assaying pollutant toxicity and bioavailability. This paper reviews the basic concepts behind the construction of whole-cell microbial biosensors for pollutant monitoring, and describes the applications of two such biosensors for detecting the bioavailability and biodegradation of Polychlorinated Biphenyls (PCBs). PMID:22205873

  2. Polychlorinated biphenyl (PCB) congeners in Mussel and other mollusc from Da Chen Island, East China Sea

    SciTech Connect

    Chu, S.G.; Xi, Z.Q.; Xu, X.B

    1995-11-01

    Polychlorinated biphenyls (PCBs) are among the most persistent and toxic pollutants in environment. Determination of these contaminants in fish, shellfish and other mollusc is very important, not only because these aquatics are important food for mankind, but also because they can bioconcentrate contaminants preferentially in their adipose tissue, and serve as biomarker of the aquatic pollution. Mussels and oysters have been widely used to monitor the pollution in the coastal environment. The aim of the study was to investigate the concentrations and the main source of PCBs in mussels and other mollusca from the coastal areas of East China Sea. 10 refs., 3 figs., 2 tabs.

  3. Microbial biodegradation of 4-chlorobiphenyl, a model compound of chlorinated biphenyls. [Achromobacter; Bacillus brevis

    SciTech Connect

    Masse, R.; Messier, F.; Peloquin, L.; Ayotte, C.; Sylvestre, M.

    1984-05-01

    The biodegradation products of 4-chlorobiphenyl were analyzed in an Achromobacter sp. strain and a Bacillus brevis strain. Both strains generated the same metabolites, with 4-chlorobenzoic acid as the major metabolic product. The authors' results corroborate previous observations whereby most bacterial strains degrade the chlorobiphenyls via a major pathway which proceeds by a hydroxylation in position 2,3 and meta-1,2 fission. However, they also detected several metabolites whose structure suggests the existence of other routes for the degradation of chlorinated biphenyls. 21 references.

  4. Investigation of hyperkeratotic activity of polybrominated biphenyls in Firemaster FF-1.

    PubMed

    Needham, L L; Hill, R H; Orti, D L; Patterson, D G; Kimbrough, R D; Groce, D F; Liddle, J A

    1982-01-01

    A polybrominated biphenyl (PBB) mixture was fractionated by normal-phase preparative high-performance liquid chromatography. The hexane fractions were concentrated and applied to rabbit ears. Only the most polar fraction produced hyperkeratosis on the rabbit ears. This active fraction was subfractionated by using the same procedure. Again, the extent of hyperkeratotic activity increased with increasing polarity. The PBBs of the largest concentration levels in the active fraction were purified by preparative gas chromatography and tested on rabbit ears. The major compounds did not demonstrate hyperkeratotic activity.

  5. Evidence of degradation of polybrominated biphenyls in soil samples from Michigan

    SciTech Connect

    Hill, R.H. Jr.; Patterson, D.G.; Orti, D.L.; Holler, J.S.; Needham, L.L.; Sirmans, S.L.; Liddle, J.A.

    1982-01-01

    Soil samples obtained from the former polybrominated biphenyls (PBB) manufacturing site in Michigan were analyzed by gas chromatography and gas chromatography with mass spectrometric detection. The results indicate significant degradation of the PBB residue in the soil sample. The soil sample with the highest concentration of PBB had the greatest degree of degradation. Principal degradation products include 2,3', 4,4', 5-pentabromobiphenyl, 2,2', 4,4', 5-pentabromobiphenyl and two unidentified tetrabromobiphenyls. The degradation pattern observed supports a photochemical decomposition mechanism. These degraded residues may be more toxic than the original Firemaster residues. The implications of the results are discussed.

  6. Chiral biphenyl diphosphines for asymmetric catalysis: stereoelectronic design and industrial perspectives.

    PubMed

    Jeulin, Séverine; de Paule, Sébastien Duprat; Ratovelomanana-Vidal, Virginie; Genêt, Jean-Pierre; Champion, Nicolas; Dellis, Philippe

    2004-04-20

    Two original chiral diphosphines, SYNPHOS and DIFLUORPHOS, have been synthesized on multigram scales. Their steric and electronic profiles have been established in comparison with the commonly used 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl and 6,6'-dimethoxy-2,2'-bis(diphenylphosphino)-1,1'-biphenyl ligands. A screening study of the four ligands in Ru(II)-catalyzed asymmetric hydrogenation of prochiral ketones and olefins has been performed. It revealed that the stereoelectronic features of the ligand and the substrate deeply influenced the enantioselectivities obtained in asymmetric hydrogenation, SYNPHOS and DIFLUORPHOS being fully complementary in terms of enantioselectivity for this reaction.

  7. Organochlorine pesticide and polychlorinated biphenyl residues in human milk from Rome (Italy) and surroundings

    SciTech Connect

    Dommarco, R.; Muccio, A.D.; Camoni, I.; Gigli, B.

    1987-12-01

    Organochlorine (OC) pesticides and polychlorinated biphenyls (PCBs) in human milk have been the subject of many studies. Surveys carried out in Italy are all eight years old with the exception of the latest work. Because of recent improvements in analytical methodology, the authors believe an up-to-date study would provide additional information. Thus, this paper presents a survey of the levels of human milk contamination, in Rome and surroundings, by organochlorine pesticides and PCBs. This survey is a part of a larger monitoring program covering also geographical areas outside of Rome.

  8. Residues of organochlorine pesticides and polychlorinated biphenyls and autopsy data for bald eagles, 1971-72

    USGS Publications Warehouse

    Cromartie, E.; Reichel, W.L.; Locke, L.N.; Belisle, A.A.; Kaiser, T.E.; Lamont, T.G.; Mulhern, B.M.; Prouty, R.M.; Swineford, D.M.

    1975-01-01

    Thirty-seven bald eagles found sick or dead in 18 States during 1971-72 were analyzed for organochlorine pesticides and polychlorinated biphenyls (PCB's). DDE and PCB's were detected in all bald eagle carcasses; 30 carcasses contained DDD and 28 contained dieldrin. Four eagles contained possibly lethal levels of dieldrin and nine eagles had been poisoned by thallium. Autopsies revealed that illegal shooting was the most common cause of mortality. Since 1964 when data were first collected, 8 of the 17 eagles obtained from Maryland, Virginia, South Carolina, and Florida possibly died from dieldrin poisoning; all four specimens from Maryland and Virginia were from the Chesapeake Bay Tidewater area.

  9. Residues of organochlorine pesticides and polychlorinated biphenyls and autopsy data for bald eagles, 1973-74

    USGS Publications Warehouse

    Prouty, R.M.; Reichel, W.L.; Locke, L.N.; Belisle, A.A.; Cromartie, E.; Kaiser, T.E.; Lamont, T.G.; Mulhern, B.M.; Swineford, D.M.

    1977-01-01

    Thirty-nine bald eagles found sick or dead in 13 States during 1969 and 1970 were analyzed for pesticide residues. Residues of DDE, dieldrin, polychlorinated biphenyls (PCB's), and mercury were detected in all bald eagle carcasses; DDD residues were detected in 38; DDT, heptachlor epoxide, and dichlorobenzophenone (DCBP) were detected less frequently. Six eagles contained possible lethal levels of dieldrin in the brain, and one contained a lethal concentration of DDE (385 ppm) in the brain together with 235 ppm of PCB's. Autopsy revealed that 18 bald eagles were illegally shot; other causes of death were impact injuries, electrocution, emaciation, and infectious diseases.

  10. Accurate oxidation potentials of 40 benzene and biphenyl derivatives with heteroatom substituents.

    PubMed

    Luo, Pu; Feinberg, Adam M; Guirado, Gonzalo; Farid, Samir; Dinnocenzo, Joseph P

    2014-10-03

    The redox equilibrium method was used to determine accurate oxidation potentials in acetonitrile for 40 heteroatom-substituted compounds. These include methoxy-substituted benzenes and biphenyls, aromatic amines, and substituted acetanilides. The redox equilibrium method allowed oxidation potentials to be determined with high precision (≤ ±6 mV). Whereas most of the relative oxidation potentials follow well-established chemical trends, interestingly, the oxidation potentials of substituted N-methylacetanilides were found to be higher than those of the corresponding acetanilides. Density functional theory calculations provided insight into the origin of these surprising results in terms of the preferred conformations of the amides versus their cation radicals.

  11. Management of the Polychlorinated Biphenyl Inventory in the Double Shell Tank (DST) System

    SciTech Connect

    LECHELT, J.A.

    2000-08-09

    This document presents the significant management features for polychlorinated biphenyl (PCB) wastes in the double-shell tank (DST) system, discussed in Sections 2.0 through 4.0. Section 2.0 delineates the decision limits for acceptance of PCB wastes into and within the DST system. Section 3.0 briefly discusses the process for obtaining a baseline PCB inventory. The PCB inventory tracking system for waste transfers into and within the DST system is described in Section 4.0. The implementation of this PCB management plan is described in Section 5.0. Section 6.0 names the organizations responsible for implementation of the plans elements.

  12. Biodegradation of biphenyl and removal of 2-chlorobiphenyl by Pseudomonas sp. KM-04 isolated from PCBs-contaminated mine impacted soil

    NASA Astrophysics Data System (ADS)

    Nam, I.; Chon, C.; Kim, J.; Kim, Y.

    2013-12-01

    The aim of the present study is to remediate the PCBs contaminated mine soil using microcosm study. For that, the naturally occurring microorganisms are stimulated and enriched in soil itself by supplementing biphenyl as well as benzoic acid. As a result the biphenyl degrading organisms are induced to degrade the PCBs contamination. From the stimulated soil, the biphenyl degrading organisms are isolated and degraded metabolites are elucidated. Pseudomonas sp. strain KM-04 was isolated from PCBs-contaminated soil in a coal mine-impacted area, and identification of bacteria was done by sequencing the 16S rRNA gene analysis. The growth of Pseudomonas sp. strain KM-04 using biphenyl as the sole carbon source was investigated by culturing in 100-mL Erlenmeyer flasks containing 10 ml sterilized MSM and 10 μg/ml biphenyl, and the ability of KM-04 to remove biphenyl and 2-chlorobiphenyl from mine soil was investigated. Metabolite formation was confirmed by liquid chromatography/atmospheric pressure chemical ionization-mass spectrometric analysis. Pseudomonas sp. strain KM-04 uses biphenyl as a sole carbon and energy source, and resting cells convert biphenyl to its metabolic intermediates, including dihydroxybiphenyl, 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid, and benzoic acid. Incubation of real soil collected from abandoned mine areas with resting cells of Pseudomonas sp. strain KM-04 for 10 days resulted in the 98.5 % of biphenyl and 82.3 % of 2-chlorobiphenyl in a slurry system. The ability of the Pseudomonas sp. strain KM-04 to bioremediate biphenyl and 2-chlorobiphenyl from abandoned mine soil was examined using soil microcosm studies under laboratory conditions. Treatment of mine soil with the Pseudomonas sp. strain KM-04 for 15 days resulted in 87.1 % reduction in biphenyl and 68.7 % in 2-chlorobiphenyl contents. The results suggest that Pseudomonas sp. strain KM-04 is a potential candidate for the biological removal of biphenyl and chlorinated derivatives

  13. Degradation of polychlorinated biphenyl mixtures in soil using phanerochaete chrysosporium in nutrient rich, non-ligninolytic conditions

    DOEpatents

    Yadav, Jagjit S.; Reddy, Chilekampalli A.; Quensen, John F.; Tiedje, James M.

    2000-01-01

    Substantial degradation of polychlorinated biphenyl (PCB) mixtures is carried out using the white rot fungus Phanerochaete chrysosporium, under nutrient, carbon and nitrogen source rich, non-ligninolytic conditions. The PCBs with various numbers of ortho, meta, and para chlorines were extensively degraded, indicating relative nonspecificity for the position of chlorine substitutions on the biphenyl ring. Maximal degradation of PCBs in a mixture was observed in malt extract medium (18.4% on a molar basis), in which most of the individual PCBs were degraded.

  14. (4R)-4-(Biphenyl-4-yl)-7-chloro-1,2,3,4-tetra­hydro­quinoline

    PubMed Central

    Theissmann, Thomas; Bolte, Michael

    2011-01-01

    The title compound, C21H18ClN, was synthesized by an enanti­oselective Brønsted acid-catalysed transfer hydrogenation reaction. The six-membered heterocycle adopts a half-chair conformation. It has the biphenyl residue in an axial position. The two rings of the biphenyl residue are almost coplanar [dihedral angle = 2.65 (9)°]. The crystal packing is stabilized by N—H⋯Cl hydrogen bonds, which connect the mol­ecules into chains running along the a axis. PMID:22064825

  15. (4R)-4-(Biphenyl-4-yl)-7-chloro-1,2,3,4-tetra-hydro-quinoline.

    PubMed

    Theissmann, Thomas; Bolte, Michael

    2011-10-01

    The title compound, C(21)H(18)ClN, was synthesized by an enanti-oselective Brønsted acid-catalysed transfer hydrogenation reaction. The six-membered heterocycle adopts a half-chair conformation. It has the biphenyl residue in an axial position. The two rings of the biphenyl residue are almost coplanar [dihedral angle = 2.65 (9)°]. The crystal packing is stabilized by N-H⋯Cl hydrogen bonds, which connect the mol-ecules into chains running along the a axis.

  16. Profiles of polychlorinated biphenyl congeners, organochlorine pesticides and butlyns in southern sea otters and their prey

    USGS Publications Warehouse

    Kannan, K.; Kajiwara, N.; Watanabe, M. E.; Nakata, H.; Thomas, N.J.; Stephenson, M.; Jessup, David A.; Tanabe, S.

    2004-01-01

    Concentrations of organochlorine pesticides, polychlorinated biphenyl (PCB) congeners, and butyltins were measured in sea otters and selected prey species (invertebrates) collected from the California (USA) coast. Polychlorinated biphenyls, DDTs (sum of p,pa??-dichlorodiphenyldichloroethylene [p,pa??-DDE], p,pa??-dichlorodiphenyldichloroethane [p,pa??-DDD], and p,pa??-DDT), and butyltins were the major contaminants found in sea otters and their prey. Lipid-normalized concentrations of PCBs and DDT in sea otter livers were 60- and 240-fold greater than those found in the prey. Great biomagnification of PCBs and DDT in sea otters is suggested to result from their high per-capita intake of diet compared with those of other marine mammals. Profiles of PCB congeners in sea otters and prey species suggest a great capacity of sea otters to biotransform lower-chlorinated congeners. Sea otters seem to possess a greater ability than cetaceans to metabolize PCBs. The 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents of non- and mono-ortho PCBs in sea otters and certain prey species were at or above the theoretical threshold for toxic effects.

  17. Net trophic transfer efficiencies of polychlorinated biphenyl congeners to lake whitefish (Coregonus clupeaformis) from their food

    USGS Publications Warehouse

    Madenjian, C.P.; O'Connor, D.V.; Rediske, R.R.; O'Keefe, J. P.; Pothoven, S.A.

    2008-01-01

    Lake whitefish (Coregonus clupeaformis) were fed rainbow smelt (Osmerus mordax) in four laboratory tanks over a 133-d experiment. At the start of the experiment, 10 to 14 of the fish in each tank were sacrificed, and the concentrations of 40 polychlorinated biphenyl (PCB) congeners within these fish were determined. Polychlorinated biphenyl congener concentrations were also determined in the 15 lake whitefish remaining in each of the four tanks at the end of the experiment as well as in the rainbow smelt fed to the lake whitefish. Each lake whitefish was weighed at the start and the end of the experiment, and the amount of food eaten by the lake whitefish during the experiment was tracked. Using these measurements, net trophic transfer efficiency (??) from the rainbow smelt to the lake whitefish in each of the four tanks was calculated for each of the 40 PCB congeners. Results showed that ?? decreased exponentially as log KOW for the congeners increased from 6 to 8. Further, ?? averaged 0.70 for the tetrachloro congeners but averaged only 0.45 for the higher chlorinated congeners. ?? 2008 SETAC.

  18. Net trophic transfer efficiencies of polychlorinated biphenyl congeners to lake trout (Salvelinus namaycush) from its prey

    USGS Publications Warehouse

    Madenjian, Charles P.; David, Solomon R.; Rediske, Richard R.; O’Keefe, James P.

    2012-01-01

    Lake trout (Salvelinus namaycush) were fed bloater (Coregonus hoyi) in eight laboratory tanks over a 135-d experiment. At the start of the experiment, four to nine fish in each tank were sacrificed, and the concentrations of 75 polychlorinated biphenyl (PCB) congeners within these fish were determined. Polychlorinated biphenyl congener concentrations were also determined in the 10 lake trout remaining in each of the eight tanks at the end of the experiment as well as in the bloater fed to the lake trout. Each lake trout was weighed at the start and the end of the experiment, and the amount of food eaten by the lake trout was recorded. Using these measurements, net trophic transfer efficiency (γ) from the bloater to the lake trout in each of the eight tanks was calculated for each of the 75 congeners. Results showed that γ did not vary significantly with the degree of chlorination of the PCB congeners, and γ averaged 0.66 across all congeners. However,γ did show a slight, but significant, decrease as logKOW increased from 6.0 to 8.2. Activity level of the lake trout did not have a significant effect on γ.

  19. Behaviour of particulate polychlorinated biphenyls and polycyclic aromatic hydrocarbons in the Scheldt estuary

    NASA Astrophysics Data System (ADS)

    Van Zoest, R.; Van Eck, G. T. M.

    Temporal and spatial variations in PolyChlorinated Biphenyl (PCB) and Polycyclic Aromatic Hydrocarbon (PAH) contents were studied in the Scheldt estuary during a one-year period (August 1987 - June 1988). Concentration levels in the Scheldt river (up to 206 ng·g -1 for individual PCB congeners and 14.6 μg·g -1 for individual PAH compounds) were higher than in any other river in the North Sea area. The annual input into the estuary was approximately 160 kg for total PCBs (10 congeners) and 12 000 kg for total PAHs (13 compounds). A small fraction of the riverine PCB and PAH load (10%) was transported to the North Sea, whereas most organic pollutants were stored in estuarine sediments. Particulate PCBs and most particulate PAHs behaved conservatively in the Scheldt estuary. PCB and PAH contents decreased when salinities increased, as a result of the mixing of riverine with marine particulates. Moreover, the PCB patterns gradually shifted in that the fraction of less chlorinated biphenyls increased compared to more chlorinated congeners. Possible mechanisms are discussed. It is suggested that emissions of PCB mixtures enriched in less chlorinated congeners took place in the proximity of the mouth of the estuary. Low molecular weight PAHs (phenanthrene, anthracene and fluoranthene) were removed in the lower salinity range. This observation may be explained by microbial degradation at low salinities under (near) anoxic conditions, favoured by the long residence time of the particulates in the high-turbidity zone.

  20. Profiles of polychlorinated biphenyl congeners, organochlorine pesticides, and butyltins in southern sea otters and their prey.

    PubMed

    Kannan, Kurunthachalam; Kajiwara, Natsuko; Watanabe, Mafumi; Nakata, Haruhiko; Thomas, Nancy J; Stephenson, Mark; Jessup, David A; Tanabe, Shinsuke

    2004-01-01

    Concentrations of organochlorine pesticides, polychlorinated biphenyl (PCB) congeners, and butyltins were measured in sea otters and selected prey species (invertebrates) collected from the California (USA) coast. Polychlorinated biphenyls, DDTs (sum of p,p'-dichlorodiphenyldichloroethylene [p,p'-DDE], p,p'-dichlorodiphenyldichloroethane [p,p'-DDD], and p,p'-DDT), and butyltins were the major contaminants found in sea otters and their prey. Lipid-normalized concentrations of PCBs and DDT in sea otter livers were 60- and 240-fold greater than those found in the prey. Great biomagnification of PCBs and DDT in sea otters is suggested to result from their high per-capita intake of diet compared with those of other marine mammals. Profiles of PCB congeners in sea otters and prey species suggest a great capacity of sea otters to biotransform lower-chlorinated congeners. Sea otters seem to possess a greater ability than cetaceans to metabolize PCBs. The 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents of non- and mono-ortho PCBs in sea otters and certain prey species were at or above the theoretical threshold for toxic effects.

  1. Assessment of exposure risk of polychlorinated biphenyls to interior least terns (Sterna antillarum)

    USGS Publications Warehouse

    Sanchez, B.C.; Caldwell, C.A.

    2008-01-01

    Risk of polychlorinated biphenyl (PCB) exposure and effects were assessed for a colony of federally endangered interior least terns (Sterna antillarum) nesting on the Bitter Lake National Wildlife Refuge (NM, USA). The colony feeds from an area on the Refuge (Hunter Marsh/Oxbow Complex) wherein fish with elevated concentrations of total PCBs have been documented. Concentrations of total PCBs in whole fish averaged 0.94 mg/kg with a maximum concentration of 2.77 mg/kg, wet weight. Estimated daily PCB intake rates by adult birds throughout their 180-d breeding season ranged from <0.01 mg/kg/d to 0.98 mg/kg/d, yielding hazard quotients that ranged from 0.01 to 21.68. Polychlorinated biphenyls pose a moderate risk to the colony of interior least terns that breed at the Bitter Lake National Wildlife Refuge, but the exposure rate is not likely to threaten their overall breeding success. ?? 2008 SETAC.

  2. Synthesis of biphenyl derivative and its application as dichroic materials in poly (vinyl alcohol) polarizing films

    NASA Astrophysics Data System (ADS)

    Shahab, Siyamak; Almodarresiyeh, Hora A.; Filippovich, Ljudmila; Kumar, Rakesh; Darroudi, Mahdieh; Hajikolaee, Fatemeh Haji

    2016-03-01

    In the present work, first time on the basis of polyvinyl alcohol (PVA) and new designed structure (Potassium 2,2‧-([1,1‧-biphenyl]-4,4‧-diylbis(azanediyl))diacetate) (I) thermostable polarizing film was created. The structure (I) was first modeled and then synthesized and obtained polarizing film absorbing at λmax = 300 nm used for electronic applications. Polarizing efficiency (PE) of polarizing film is 96% at stretching degree (Rs) 4.0. On the basis of PVA, Potassium 2,2‧-([1,1‧-biphenyl]-4,4‧-diylbis(azanediyl))diacetate (I), Sodium 2-hydroxy-5-((2-methoxy-4-((4-sulfonatophenyl)diazenyl)phenyl)diazenyl)benzoate (II) and commercial dye (Congo Red) thermostable polarizing film for wide spectral range of spectrum (λmax = 288-561 nm) was developed. During the work it was established that oriented PVA-films is phenomenon of anisotropy of thermal conductivity (λ||/λ⊥). It is very important for creation of thermostable polarizing films. Thermal conductivity in a direction of orientation (λ||) is higher than in a direction perpendicular orientations (λ⊥). The optimization of the molecule (1) was carried out by Density Functional Theory (DFT) using B3LYP/6-311 + G* method. Electronic absorption spectrum of the molecule (I) in dimethylformamide (DMF) solution was calculated using TDB3LYP/6-311 + G* level. The nature of absorption bands in the UV spectral region was interpreted.

  3. Assessing atmospheric concentration of polychlorinated biphenyls by evergreen Rhododendron maximum next to a contaminated stream.

    PubMed

    Dang, Viet D; Walters, David M; Lee, Cindy M

    2016-09-01

    Conifers are often used as an air passive sampler, but few studies have focused on the implication of broadleaf evergreens to monitor atmospheric semivolatile organic compounds such as polychlorinated biphenyls (PCBs). In the present study, the authors used Rhododendron maximum (rhododendron) growing next to a contaminated stream to assess atmospheric PCB concentrations. The present study area was located in a rural setting and approximately 2 km downstream of a former capacitor plant. Leaves from the same mature shrubs were collected in late fall 2010 and winter and spring 2011. Polychlorinated biphenyls were detected in the collected leaves, suggesting that rhododendron can be used as air passive samplers in rural areas where active sampling is impractical. Estimated ΣPCB (47 congeners) concentrations in the atmosphere decreased from fall 2010 to spring 2011 with concentration means at 3990 pg m(-3) , 2850 pg m(-3) , and 931 pg m(-3) in fall 2010, winter 2011, and spring 2011, respectively. These results indicate that the atmospheric concentrations at this location continue to be high despite termination of active discharge from the former industrial source. Leaves had a consistent pattern of high concentrations of tetra-CBs and penta-CBs similar to the congener distribution in polyethylene passive samplers deployed in the water column, suggesting that volatilized PCBs from the stream were the primary source of contaminants in rhododendron leaves. Environ Toxicol Chem 2016;35:2192-2198. © 2016 SETAC. © 2016 SETAC.

  4. Flavonoids biotransformation by bacterial non-heme dioxygenases, biphenyl and naphthalene dioxygenase.

    PubMed

    Seo, Jiyoung; Kang, Su-Il; Kim, Mihyang; Han, Jaehong; Hur, Hor-Gil

    2011-07-01

    This review details recent progresses in the flavonoid biotransformation by bacterial non-heme dioxygenases, biphenyl dioxygenase (BDO), and naphthalene dioxygenase (NDO), which can initially activate biphenyl and naphthalene with insertion of dioxygen in stereospecfic and regiospecific manners. Flavone, isoflavone, flavanone, and isoflavanol were biotransformed by BDO from Pseudomonas pseudoalcaligenes KF707 and NDO from Pseudomonas sp. strain NCIB9816-4, respectively. In general, BDO showed wide range of substrate spectrum and produced the oxidized products, whereas NDO only metabolized flat two-dimensional substrates of flavone and isoflavone. Furthermore, biotransformation of B-ring skewed substrates, flavanone and isoflavanol, by BDO produced the epoxide products, instead of dihydrodiols. These results support the idea that substrate-driven reactivity alteration of the Fe-oxo active species may occur in the active site of non-heme dioxygenases. The study of flavonoid biotransformation by structurally-well defined BDO and NDO will provide the substrate structure and reactivity relationships and eventually establish the production of non-plant-originated flavonoids by means of microbial biotechnology.

  5. Enhanced Polychlorinated Biphenyl Removal in a Switchgrass Rhizosphere by Bioaugmentation with Burkholderia xenovorans LB400

    PubMed Central

    Liang, Yi; Meggo, Richard; Hu, Dingfei; Schnoor, Jerald L.; Mattes, Timothy E.

    2014-01-01

    Phytoremediation makes use of plants and associated microorganisms to clean up soils and sediments contaminated with inorganic and organic pollutants. In this study, switchgrass (Panicum virgatum) was used to test for its efficiency in improving the removal of three specific polychlorinated biphenyl (PCB) congeners (PCB 52, 77 and 153) in soil microcosms. The congeners were chosen for their ubiquity, toxicity, and recalcitrance. After 24 weeks of incubation, loss of 39.9 ± 0.41% of total PCB molar mass was observed in switchgrass treated soil, significantly higher than in unplanted soil (29.5 ± 3.4%) (p<0.05). The improved PCB removal in switchgrass treated soils could be explained by phytoextraction processes and enhanced microbial activity in the rhizosphere. Bioaugmentation with Burkholderia xenovorans LB400 was performed to further enhance aerobic PCB degradation. The presence of LB400 was associated with improved degradation of PCB 52, but not PCB 77 or PCB 153. Increased abundances of bphA (a functional gene that codes for a subunit of PCB-degrading biphenyl dioxygenase in bacteria) and its transcript were observed after bioaugmentation. The highest total PCB removal was observed in switchgrass treated soil with LB400 bioaugmentation (47.3 ± 1.22 %), and the presence of switchgrass facilitated LB400 survival in the soil. Overall, our results suggest the combined use of phytoremediation and bioaugmentation could be an efficient and sustainable strategy to eliminate recalcitrant PCB congeners and remediate PCB-contaminated soil. PMID:25246731

  6. Enhancing effect of spawning on elimination of a persistent polychlorinated biphenyl from female yellow perch

    SciTech Connect

    Vodicnik, M.J.; Peterson, R.E.

    1985-08-01

    Distribution and elimination of 2,5,2',5'-tetrachloro(14C)biphenyl (4-CB) were studied for 6 months after exposing sexually mature female yellow perch to the compound in water and transferring them to flowing 4-CB-free water. Perch that were exposed in January spawned in May, and the study was terminated in June. During the first 41/2 months after exposure, the t1/2 for whole-body elimination was 22 weeks, primarily by elimination of 4-CB from the viscera and carcass. During spawning, enhanced elimination (t1/2 less than 0.7 weeks) was due to the voiding of eggs containing 4-CB. After spawning, whole-body elimination returned to a slower rate (t1/2 = 16.3 weeks). Prior to the enhancement in 4-CB elimination rate during spawning, there was a redistribution of 4-CB residues within the body of the perch which was characterized by a transfer of 4-CB residues from primarily the carcass and viscera to eggs. Two weeks after exposure, 30% of the initial 4-CB body burden was distributed to the eggs, whereas just prior to spawning, about 50% was present in this tissue. These findings demonstrate that egg maturation and spawning result in a significant reduction in the body burden of a persistent polychlorinated biphenyl in a lean-fish species.

  7. Potential for Polychlorinated Biphenyl Biodegradation in Sediments from Indiana Harbor and Ship Canal

    PubMed Central

    Liang, Yi; Martinez, Andres; Hornbuckle, Keri C.; Mattes, Timothy E.

    2014-01-01

    Polychlorinated biphenyls (PCBs) are carcinogenic, persistent, and bioaccumulative contaminants that pose risks to human and environmental health. In this study, we evaluated the PCB biodegradation of sediments from Indiana Harbor and Ship Canal (IHSC), a PCB-contaminated site (average PCB concentration = 12,570 ng/g d.w.). PCB congener profiles and bacterial community structure in a core sediment sample (4.57 m long) were characterized. Analysis of vertical PCB congener profile patterns in sediment and pore water strongly suggest that in situ dechlorination occurred in sediments. However, 16S rRNA genes from putative PCB-dechlorinating Chloroflexi were relatively more abundant in upper 2 m sediments, as were genes indicative of aerobic biodegradation potential (i.e. biphenyl dioxygenase (bphA)). Characterization of the bacterial community by terminal restriction fragment length polymorphism and comparison of these with sediment and pore water PCB congener profiles with the Mantel test revealed a statistical correlation (p<0.001). Sequences classified as Acinetobacter and Acidovorax were highly abundant in deep sediments. Overall, our results suggest that PCB dechlorination has already occurred, and that IHSC sediments have the potential for further aerobic and anaerobic PCB biodegradation. PMID:24764649

  8. Pollutants make rheumatic diseases worse: Facts on polychlorinated biphenyls (PCBs) exposure and rheumatic diseases.

    PubMed

    Abella, Vanessa; Pérez, Tamara; Scotece, Morena; Conde, Javier; Pirozzi, Claudio; Pino, Jesús; Lago, Francisca; González-Gay, Miguel Ángel; Mera, Antonio; Gómez, Rodolfo; Gualillo, Oreste

    2016-07-15

    Polychlorinated biphenyls (PCBs) are persistent organic pollutants that bioaccumulate in adipose tissue, disturbing its metabolism and the balance of adipokines, related to obesity. The altering secretion pattern of adipokines from the adipose tissue and the increasing mechanical load in weight-bearing joints presented in obesity condition, are risk factors for osteoarthritis development. The most prevalent rheumatic diseases, osteoarthritis and rheumatoid arthritis, are chronic conditions that target the whole joints, leading to increasing disability and health care cost. The goal of this focused review is to summarize the current knowledge on the role of PCBs in osteoarthritis and rheumatoid arthritis pathogenesis. A PubMed search was managed using keywords as "rheumatic diseases", "polychlorinated biphenyls", "obesity" and "endocrine disruption". The incidence of rheumatoid arthritis has been reported to be increased especially in urban areas in industrialized countries, emphasizing the importance of environment in the pathogenesis of rheumatic diseases. Analysis of two cohorts exposed to PCBs food contamination showed high incidence of arthritis. In addition, PCBs in serum correlated positively with the prevalence of self-reported arthritis. Few studies support the hypothesis that osteoarthritis development could be related to PCBs induction of chondrocytes apoptosis. Evidences have emerged for a relationship between PCBs and development of several types of arthritis. Further research is encouraged to determine the correlation between PCBs exposure and the development of rheumatic diseases. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Maternal Exposure to Polybrominated and Polychlorinated Biphenyls: Infant Birth Weight and Gestational Age

    PubMed Central

    Givens, Marjory L.; Small, Chanley M.; Terrell, Metrecia L.; Cameron, Lorraine L.; Blanck, Heidi Michels; Tolbert, Paige E.; Rubin, Carol; Henderson, Alden K.; Marcus, Michele

    2007-01-01

    Understanding the influence of maternal exposures on gestational age and birth weight is essential given that pre-term and/or low birth weight infants are at risk for increased mortality and morbidity. We performed a retrospective analysis of a cohort exposed to polybrominated biphenyls (PBB) through accidental contamination of cattle feed and polychlorinated biphenyls (PCB) through residual contamination in the geographic region. Our study population consisted of 444 mothers and their 899 infants born between 1975 and 1997. Using restricted maximum likelihood estimation, no significant association was found between estimated maternal serum PBB at conception or enrollment PCB levels and gestational age or infant birth weight in unadjusted models or in models that adjusted for maternal age, smoking, parity, infant gender, and decade of birth. For enrollment maternal serum PBB, no association was observed for gestational age. However, a negative association with high levels of enrollment maternal serum PBB and birth weight was suggested. We also examined the birth weight and gestational age among offspring of women with the highest (10%) PBB or PCB exposure, and observed no significant association. Because brominated compounds are currently used in consumer products and therefore, are increasingly prevalent in the environment, additional research is needed to better understand the potential relationship between in utero exposure to brominated compounds and adverse health outcomes. PMID:17617441

  10. Net trophic transfer efficiencies of polychlorinated biphenyl congeners to lake trout (Salvelinus namaycush) from its prey.

    PubMed

    Madenjian, Charles P; David, Solomon R; Rediske, Richard R; O'Keefe, James P

    2012-12-01

    Lake trout (Salvelinus namaycush) were fed bloater (Coregonus hoyi) in eight laboratory tanks over a 135-d experiment. At the start of the experiment, four to nine fish in each tank were sacrificed, and the concentrations of 75 polychlorinated biphenyl (PCB) congeners within these fish were determined. Polychlorinated biphenyl congener concentrations were also determined in the 10 lake trout remaining in each of the eight tanks at the end of the experiment as well as in the bloater fed to the lake trout. Each lake trout was weighed at the start and the end of the experiment, and the amount of food eaten by the lake trout was recorded. Using these measurements, net trophic transfer efficiency (γ) from the bloater to the lake trout in each of the eight tanks was calculated for each of the 75 congeners. Results showed that γ did not vary significantly with the degree of chlorination of the PCB congeners, and γ averaged 0.66 across all congeners. However, γ did show a slight, but significant, decrease as log K(OW) increased from 6.0 to 8.2. Activity level of the lake trout did not have a significant effect on γ. Copyright © 2012 SETAC.

  11. Effect of ozonation on polychlorinated biphenyl degradation and on soil physico-chemical properties.

    PubMed

    Javorská, Hana; Tlustos, Pavel; Komárek, Michael; Lestan, Domen; Kaliszová, Regina; Száková, Jirina

    2009-01-30

    The objectives of this study were to investigate the effectiveness of ozone treatment on degradation of polychlorinated biphenyl (PCB) contaminated soils and to observe the subsequent changes in soil physico-chemical properties. Furthermore, the ability of plants to grow on the ozone-treated soils was evaluated. Soils with different physico-chemical characteristics spiked with seven PCB congeners in two different time periods were chosen. Ozonation was more efficient for PCB degradation in freshly spiked soils and the removal efficiency increased with increasing ozonation time. The highest decrease was found in the soil with a lower soil organic matter (SOM) content and a coarser soil structure indicating the substantial effect of soil characteristics on the efficiency of ozonation. The composition of individual PCB congeners changed in all treatments in terms of higher accumulation rate of highly chlorinated biphenyls with a higher ozonation time. Increased mobility of several elements, changes in SOM content and in soil pH were detected after ozonation. Vulnerability of plants to these modifications was documented on rape seedlings. No inhibition in growth during any treatment and predominantly higher concentration of PCB in non-ozonated treatments were observed. Results suggest that this method can present a promising environmental friendly remediation technology for PCB contaminated soils.

  12. Ab initio study of the thermopower of biphenyl-based single-molecule junctions

    NASA Astrophysics Data System (ADS)

    Bürkle, M.; Zotti, L. A.; Viljas, J. K.; Vonlanthen, D.; Mishchenko, A.; Wandlowski, T.; Mayor, M.; Schön, G.; Pauly, F.

    2012-09-01

    By employing ab initio electronic-structure calculations combined with the nonequilibrium Green's function technique, we study the dependence of the thermopower Q on the conformation in biphenyl-based single-molecule junctions. For the series of experimentally available biphenyl molecules, alkyl side chains allow us to gradually adjust the torsion angle ϕ between the two phenyl rings from 0∘ to 90∘ and to control in this way the degree of π-electron conjugation. Studying different anchoring groups and binding positions, our theory predicts that the absolute values of the thermopower decrease slightly towards larger torsion angles, following an a+bcos2ϕ dependence. The anchoring group determines the sign of Q and a,b simultaneously. Sulfur and amine groups give rise to Q,a,b>0, while for cyano, Q,a,b<0. The different binding positions can lead to substantial variations of the thermopower mostly due to changes in the alignment of the frontier molecular orbital levels and the Fermi energy. We explain our ab initio results in terms of a π-orbital tight-binding model and a minimal two-level model, which describes the pair of hybridizing frontier orbital states on the two phenyl rings. The variations of the thermopower with ϕ seem to be within experimental resolution.

  13. Continuous coculture degradation of selected polychlorinated biphenyl congeners by Acinetobacter spp. in an aerobic reactor system

    SciTech Connect

    Adriaens, P.; Focht, D.D. )

    1990-07-01

    A coculture of two Acinetobacter spp. was applied to degrade polychlorinated biphenyls during a 42-day incubation study in a continuous aerobic fixed-bed reactor system, filled with polyurethane foam boards as support for bacterial biofilm development. The reactor was supplied with mineral medium containing 500 ppm sodium benzoate as a growth (primary) substrate, while the incoming airstream was saturated with biphenyl vapors to induce for PCB cometabolism in Acinetobacter sp. strain P6. The chlorobenzoates thus generated from 4,4{prime}-dichlorobiphenyl (4,4{prime}-DCBP), 3,4-dichlorobiphenyl (3,4-DCBP), and 3,3{prime},4,4{prime}-tetrachlorobiphenyl were further metabolized by Acinetobacter sp. strain 4-CB1. The chlorobenzoate metabolites, as well as ring-fission product ({lambda}{sub max} = 442 nm) from the PCB congeners, accounted for the degradation of 63% (2.8 mM) of the 4,4{prime}-DCBP, 100% (0.5 mM) of the 3,4-DCBP, and 32% (0.12 mM) of the 3,3{prime},4,4{prime}-TCBP, the biofilm responded with a concurrent higher release of chlorobenzoates and chloride through cosubstrate utilization.

  14. Profiles of polychlorinated biphenyls (PCBs) in cement kilns co-processing solid waste.

    PubMed

    Jin, Rong; Zhan, Jiayu; Liu, Guorui; Zhao, Yuyang; Zheng, Minghui; Yang, Lili; Wang, Mei

    2017-05-01

    Co-incineration of sewage sludge in cement kilns can be used for its disposal. In the present study, samples were collected from three cement production runs where sewage sludge and other wastes (e.g. municipal solid waste, waste acid and wet sewage sludge) were co-processed. The samples were analyzed for polychlorinated biphenyls (PCBs). The dioxin-like (dl)-PCB concentrations in the stack gases from run 1, 2, and 3 were 344.6, 548.7, and 104.3 pg m(-3), respectively. The toxic equivalency (TEQs) values for runs 1, 2, and 3 were 5.6, 8.9, and 0.7 pg TEQ Nm(-3), respectively. Calculation of net emissions for the three runs indicated that the co-incineration of other waste in addition to sewage sludge in cement kilns would not increase emission of the dl-PCBs. PCB concentrations in samples from the suspension boiler and humidifier tower, kiln-end bag filter, and cyclone preheater were much higher than those in samples from the kiln head area, indicating that these stages will be important for controlling PCB formation. Chlorinated biphenyl (CB)-77, CB-105 and CB-118 were the major dl-PCB congeners, CB-52, CB-101 were the major indicator PCB congeners, and tetra-CB to hexa-CB were the major homologues for the total input or output materials.

  15. Potential of autochthonous fungal strains isolated from contaminated soils for degradation of polychlorinated biphenyls.

    PubMed

    Mouhamadou, Bello; Faure, Mathieu; Sage, Lucile; Marçais, Johanna; Souard, Florence; Geremia, Roberto A

    2013-04-01

    Up to now, most studies on polychlorinated biphenyl (PCB) bioremediation have examined the ability of model fungal strains to biodegrade PCBs. Yet, there is limited information concerning the potential of autochthonous filamentous fungal strains in the biodegradation of PCBs and their possible use in the environmental technologies. In this study, we investigated the capacity of autochthonous fungal strains in the biodegradation of PCBs by isolating 24 taxa from former industrial sites highly contaminated by PCBs. Microscopic and molecular analyses using the internal transcribed spacer (ITS) region revealed that the fungal strains belonged to the phyla Ascomycota (19 strains) and Zygomycota (five strains). The chromatography gas analysis revealed evidence of degradation of seven PCB congeners. With the exception of Circinella muscae which presented no degradation potential, the other fungal strains exhibited a rate of biodegradation ranging from 29 to 85 % after 7 d of incubation in liquid medium. Among these strains, Doratomyces nanus, Doratomyces purpureofuscus, Doratomyces verrucisporus, Myceliophthora thermophila, Phoma eupyrena, and Thermoascus crustaceus showed remarkable degradation ability (>70 %) regardless of the number of chlorine substituents on the biphenyl nucleus and a high tolerance towards PCBs. To our knowledge, this is the first study that demonstrates the ability of PCB degradation by these species and indicates the potential effectiveness of some autochthonous fungal strains in bioremediation systems. Copyright © 2013 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  16. Quercetin ameliorates polychlorinated biphenyls-induced testicular DNA damage in rats.

    PubMed

    Lovato, F L; de Oliveira, C R; Adedara, I A; Barbisan, F; Moreira, K L S; Dalberto, M; da Rocha, M I U M; Marroni, N P; da Cruz, I B; Costabeber, I B

    2016-02-01

    Polychlorinated biphenyls (PCBs) are a group of environmental contaminants widely reported to cause gonadal toxicity in both humans and animals. This study investigated the amelioratory role of quercetin in PCBs-induced DNA damage in male Wistar rats. Polychlorinated biphenyls were administered intraperitoneally at a dose of 2 mg kg(-1) alone or in combination with quercetin (orally) at 50 mg kg(-1) for 25 days. Quercetin modulation of PCBs-induced gonadal toxicity was evaluated using selected oxidative stress indices, comet assay, measurement of DNA concentration and histology of the testes. Administration of PCBs alone caused a significant (P < 0.05) depletion in the total thiol level in testes of treated rats. Conversely, the levels of reactive oxygen species (ROS) and thiobarbituric acid reactive substances (TBARS) production were markedly elevated in testes of PCBs-treated rats compared with control. Further, PCBs exposure produced statistically significant increases in DNA tail migration, degraded double-stranded DNA (dsDNA) concentration and histological alterations of testes of the treated rats compared to control. Quercetin cotreatment significantly improved the testicular antioxidant status, decreased DNA fragmentation and restored the testicular histology, thus demonstrating the protective effect of quercetin in PCBs-treated rats.

  17. Serum Polybrominated Biphenyls (PBBs) and Polychlorinated Biphenyls (PCBs) and Thyroid Function among Michigan Adults Several Decades after the 1973-1974 PBB Contamination of Livestock Feed.

    PubMed

    Jacobson, Melanie H; Darrow, Lyndsey A; Barr, Dana Boyd; Howards, Penelope P; Lyles, Robert H; Terrell, Metrecia L; Smith, Alicia K; Conneely, Karen N; Marder, M Elizabeth; Marcus, Michele

    2017-09-26

    In 1973-1974, Michigan residents were exposed to polybrominated biphenyls (PBBs) through an accidental contamination of the food supply. Residents were enrolled in a registry assembled after the incident, and they and their children participated in follow-up studies to assess subsequent health outcomes. We evaluated associations between serum PBBs and polychlorinated biphenyls (PCBs) and markers of thyroid function among Michigan adults. Serum concentrations of four PBB and four PCB congeners were measured at least once in 753 adults, including 79 women who participated in a 2004-2006 study and 683 women and men with follow-up during 2012-2015. Participants completed questionnaires on health conditions (including physician-diagnosed thyroid disease), behaviors, and demographics. Thyroid hormones were measured in a subset without thyroid disease (n=551). In multivariable linear regression models, PBB and PCB congener concentrations, on both the volume (nanogram/milliliter) and lipid (nanogram/gram lipid) basis, were assessed in relation to thyroid hormones. Logistic regression models were used to estimate associations between serum PBBs and PCBs and thyroid disease. Thyroid disease was common (18% overall; 25% among women). Among women, all odds ratios (ORs) for PBB-153 and thyroid disease were positive for quintiles above the reference level, but estimates were imprecise and were without a monotonic increase. For an interquartile range (IQR) increase in PBB-153 (0.43 ng/mL), the OR (any thyroid disease)=1.12; (95% CI: 0.83, 1.52) (n=105 cases); for hypothyroidism, OR=1.35 (95% CI: 0.86, 2.13) (n=49 cases). There were 21 cases of thyroid disease in men [OR=0.69 (95% CI: 0.33); 1.44 for an IQR increase (0.75 ng/mL) in serum PBB-153]. PCB congeners were statistically significantly associated with greater total and free thyroxine and total triiodothyronine among women and with total and free triiodothyronine among men in lipid-standardized models. We

  18. Comparative induction of xenobiotic metabolism in rodent kidney, testis and liver by commercial mixtures of polybrominated biphenyls and polychlorinated biphenyls, phenobarbital and 3-methylcholanthrene: absolute and temporal effects.

    PubMed

    Kluwe, W M; Hook, J B

    1981-01-01

    Male Fischer 344 rats were killed at various times after single or multiple treatments with polybrominated biphenyls (PBB), polychlorinated biphenyls (PCB), sodium phenobarbital (NaPB) or 3-methylcholanthrene (3MC). p-Chloro-N-methyl-aniline N-demethylase (PCNMA) and aryl hydrocarbon hydroxylase (AHH) activities were determined in the 14 000 g supernatant fraction (postmitochondrial supernate, PMS) of renal, testicular and hepatic homogenates. Cytochrome P-450 (p-450) concentrations were determined in the 100 000 g pellet fractions of the same homogenates and the effects of enzyme induction on the sensitivities of AHH in PMS to inhibition by alpha-napthoflavone (ANF) and metyrapone (MET) in vitro were determined. Single treatments with PBB or PCB induced hepatic P-450 only, while multiple treatments with PBB, PCB or 3MC induced both renal and hepatic P-450; NaPB induced only hepatic P-450, while testicular P-450 concentration was unaffected by the inducers. Treatments with PBB, PCB or 3MC shifted the Soret maxima of renal and hepatic dithionite-reduced P-450 difference spectra to shorter wavelengths. Multiple treatments with PBB, PCB or 3MC increased renal and hepatic AHH activities, but NaPB induced hepatic AHH only. Renal AHH activity was increased more rapidly than hepatic AHH after a single treatment with PBB, PCB or 3MC and returned more rapidly to control. The renal AHH induced by PBB and PCB, like that induced by 3MC, was more sensitive to inhibition by ANF in vitro than was renal AHH from naive rats. Hepatic AHH induced by PBB and PCB, unlike that induced by NaPB or 3MC, exhibited no net alterations in sensitivities to the inhibitory effects of ANF or MET. Testicular AHH activity was not induced by PBB, PCB , NaPB or 3MC. Multiple treatments with PBB, PCB or NaPB increased hepatic, but not renal or testicular PCNMA activities. The organ-specificity and time-dependency of the effects of PBB, PCB, NaPB and 3MC on P-450 concentrations and AHH activities

  19. Laboratory study of polychlorinated biphenyl (PCB) contamination and mitigation in buildings; Part 1. Emissions from selected primary sources

    EPA Science Inventory

    Polychlorinated biphenyls (PCBs) are a class of 209 organic compounds, known as congeners, with the chemical formula of C12H1O-xClx, where x is the number of chlorine atoms in the range of 1 to 10. Different mixtures of these congeners were sold under many brands and trade names ...

  20. Determination of levels of polychlorinated biphenyls (PCBs) present in caulk and window glazing material samples from older buildings

    EPA Science Inventory

    Levels of polychlorinated biphenyls (PCBs) in caulk and window glazing material samples from older buildings were determined, using a method developed for this purpose. This method was evaluated by analyzing a combination of 47 samples of caulk, glazing materials, including quali...

  1. Global contamination of coplanar polybrominated/chlorinated biphenyls (Co-PXBs) in the market fishes from Japan.

    PubMed

    Ohta, Souichi; Tokusawa, Hidekazu; Nakao, Teruyuki; Aozasa, Osamu; Miyata, Hideaki; Alaee, Mehran

    2008-08-01

    Polybrominated chlorinated biphenyls (PXBs, X=Br, Cl) are a group of environmental contaminants that have not been studied previously. The introduction of the second halogen to the biphenyl backbone increases the number of possible congeners to more than 9000. Only a limited number of PXBs are commercially available. In order to determine the occurrence of these compounds in environmental matrices, an isotope dilution HRGC/HRMS method for determination of five co-planar polybrominated/chlorinated biphenyls (Co-PXBs) in biota was developed. The method detection limit for these compounds ranged between 0.05 and 0.5 pg/g for 4'-monobromo-3,3',4,5-tetrachlorobiphenyl and 3',4',5'-tribromo-3,4-dichlorobiphenyl, respectively. Concentrations of five co-planar polybrominated and chlorinated biphenyls in eighteen different fish fillets from Japanese markets ranged between 4 and 46 pg/g wet weight for mink whale and young yellow-tail fish. These values are substantially lower than those reported for Co-PCBs; however, it should be noted that due to the unavailability of standards, identification and quantification of all the isomers was not possible.

  2. Laboratory study of polychlorinated biphenyl (PCB) contamination and mitigation in buildings; Part 1. Emissions from selected primary sources

    EPA Science Inventory

    Polychlorinated biphenyls (PCBs) are a class of 209 organic compounds, known as congeners, with the chemical formula of C12H1O-xClx, where x is the number of chlorine atoms in the range of 1 to 10. Different mixtures of these congeners were sold under many brands and trade names ...

  3. USE OF PLANT AND EARTHWORM BIOASSYS TO EVALUATE REMEDIATION OF SOIL FROM A SITE CONTAMINATED WITH POLYCHLORINATED BIPHENYLS

    EPA Science Inventory

    Soil from a site heavily contaminated with polychlorinated biphenyls (PCBs) was treated with a pilot-scale, solvent extraction tehnology. Bioassays in earthworms and plants were used to examine the efficacy of the remediation process for reducing the toxicity of the soil. The ear...

  4. USE OF PLANT AND EARTHWORM BIOASSAYS TO EVALUATE REMEDIATION OF SOIL FROM A SITE CONTAMINATED WITH POLYCHLORINATED BIPHENYLS

    EPA Science Inventory

    Soil from a site heavily contaminated with polychlorinated biphenyls (PCBs) was treated with a pilot-scale, solvent extraction technology. Bioassays in earthworms and plants were used to examine the efficacy of the remediation process for reducing the toxicity of the soil. The ...

  5. SEQUENCE SIMILARITIES IN THE GENES ENCODING POLY- CHLORINATED BIPHENYL DEGRADATION BY PSEUDOMONAS STRAIN LB400 AND ALCALIGENES EUTROPHUS H850

    EPA Science Inventory

    DNA-DNA hybridization was used to compare the Pseudomonas strain LB400 genes for polychlorinated biphenyl (PCB) degradation with those from seven other PCB-degrading strains. Significant hybridization was detected to the genome of Alcaligenes eutrophus H850, a strain similar to L...

  6. A SIMPLE AND FAST EXTRACTION METHOD FOR ORGANOCHLORINE PESTICIDES AND POLYCHLORINATED BIPHENYLS IN SMALL VOLUMES OF AVIAN SERUM

    EPA Science Inventory

    A solid-phase extraction (SPE) method was developed using 8 M urea to desorb and extract organochlorine pesticides (OCs) and polychlorinated biphenyls (PCBs) from avian serum for analysis by capillary gas chromatography with electron capture detection (GC-ECD). The analytes were ...

  7. Levels of Polychlorinated Dibenzo-p-Dibenzofurans, and Biphenyls in Southern Mississippi Catfish and Estimation of Potential.

    EPA Science Inventory

    Fish consumption has been classified as one of the primary pathways of exposure to polychlorinated dibenzo-p-dioxins, dibenzofurans (PCDD/Fs) and biphenyls (PCBs). In this study, we evaluated tissue levels of the 17 laterally-substituted PCDD/Fs, 12 dioxin-like PCBs, and 97 non-...

  8. A SIMPLE AND FAST EXTRACTION METHOD FOR ORGANOCHLORINE PESTICIDES AND POLYCHLORINATED BIPHENYLS IN SMALL VOLUMES OF AVIAN SERUM

    EPA Science Inventory

    A solid-phase extraction (SPE) method was developed using 8 M urea to desorb and extract organochlorine pesticides (OCs) and polychlorinated biphenyls (PCBs) from avian serum for analysis by capillary gas chromatography with electron capture detection (GC-ECD). The analytes were ...

  9. EVIDENCE THAT CA2+ SIGNALING AND TRANSCRIPTION FACTOR (CREB) ACTIVITIES STIMULATED BY POLYCHLORINATED BIPHENYLS ARE LOCALIZED TO DEVELOPING NEURONS.

    EPA Science Inventory

    Using a mixed culture of neonatal cortical cells, we have demonstrated that the polychlorinated biphenyl (PCB) mixture Aroclor 1254 (A1254) induces complex Ca2+i signals involving multiple receptors/channels (Inglefield and Shafer, J.Pharm.Exp.Ther. 295:105) and also activates/ p...

  10. Polychlorinated biphenyls: Occurrence in sediments and soils. (Latest citations from the Selected Water Resources Abstracts database). Published Search

    SciTech Connect

    Not Available

    1993-11-01

    The bibliography contains citations concerning field and laboratory analyses of polychlorinated biphenyls (PCBs) in sediments and soils. Topics include site studies; chemical analyses of adsorption-desorption processes; decomposition in soils, including biodegradation; and bioaccumulation. Detection methods and instrumention, and the impact of dredging in contaminated areas are also discussed. (Contains 250 citations and includes a subject term index and title list.)

  11. Polychlorinated biphenyls: Occurrence in sediments and soils. (Latest citations from the Selected Water Resources Abstracts database). Published Search

    SciTech Connect

    Not Available

    1993-02-01

    The bibliography contains citations concerning field and laboratory analyses of polychlorinated biphenyls (PCBs) in sediments and soils. Topics include site studies; chemical analyses of adsorption-desorption processes; decomposition in soils, including biodegradation; and bioaccumulation. Detection methods and instrumention, and the impact of dredging in contaminated areas are also discussed. (Contains 250 citations and includes a subject term index and title list.)

  12. Polychlorinated biphenyls: Occurrence in sediments and soils. (Latest citations from the Selected Water Resources Abstracts database). Published Search

    SciTech Connect

    Not Available

    1994-08-01

    The bibliography contains citations concerning field and laboratory analyses of polychlorinated biphenyls (PCBs) in sediments and soils. Topics include site studies; chemical analyses of adsorption-desorption processes; decomposition in soils, including biodegradation; and bioaccumulation. Detection methods and instrumention, and the impact of dredging in contaminated areas are also discussed. (Contains 250 citations and includes a subject term index and title list.)

  13. Oxidative ring cleavage of low chlorinated biphenyl derivatives by fungi leads to the formation of chlorinated lactone derivatives.

    PubMed

    Sietmann, Rabea; Gesell, Manuela; Hammer, Elke; Schauer, Frieder

    2006-07-01

    The yeast Trichosporon mucoides and the filamentous fungus Paecilomyces lilacinus as biphenyl oxidizing organisms are able to oxidize chlorinated biphenyl derivatives. Initial oxidation of derivatives chlorinated at C4 position started at the non-halogenated ring and went on up to ring cleavage. The products formed were mono- and dihydroxylated 4-chlorobiphenyls, muconic acid derivatives 2-hydroxy-4-(4-chlorophenyl)-muconic acid and 2-hydroxy-5-(4-chlorophenyl)-muconic acid as well as the corresponding lactones 4-(4-chlorophenyl)-2-pyrone-6-carboxylic acid and 3-(4-chlorophenyl)-2-pyrone-6-carboxylic acid. Altogether T. mucoides formed 12 products and P. lilacinus accumulated five products. Whereas the rate of the first oxidation step at 4-chlorobiphenyl seems to be diminished by the decreased bioavailability of the compound, no considerable differences were observed between the degradation of 4-chloro-4'-hydroxybiphenyl and 4-hydroxybiphenyl. Twofold chlorinated biphenyl derivatives did not serve as substrates for oxidation by either organism with the exception of 2,2'-dichlorobiphenyl, transformed by the yeast Trichosporon mucoides to two monohydroxylated derivatives. The results show, that soil fungi may contribute to the aerobic degradation of low chlorinated biphenyls accumulating from anaerobic dehalogenation of PCB by bacteria.

  14. The Relationship between Prenatal and Postnatal Exposure to Polychlorinated Biphenyls (PCBs) and Cognitive, Neuropsychological, and Behavioral Deficits: A Critical Appraisal

    ERIC Educational Resources Information Center

    Cicchetti, Domenic V.; Kaufman, Alan S.; Sparrow, Sara S.

    2004-01-01

    Our purpose in this report is to evaluate scientifically that body of literature relating the effects of prenatal and postnatal exposure to polychlorinated biphenyls (PCBs) upon neurobehavioral, health-related, and cognitive deficits in neonates, developing infants, children, and adults. The data derive from seven cohorts: six cohorts of mothers…

  15. 21 CFR 109.15 - Use of polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... environmental stability and tendency to survive and be concentrated through the food chain. The judgment as to... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Use of polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials. 109.15 Section 109.15 Food and Drugs FOOD AND DRUG...

  16. 21 CFR 500.45 - Use of polychlorinated biphenyls (PCB's) in the production, handling, and storage of animal feed.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... its environmental stability and tendency to survive and be concentrated through the food chain. The... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Use of polychlorinated biphenyls (PCB's) in the production, handling, and storage of animal feed. 500.45 Section 500.45 Food and Drugs FOOD AND DRUG...

  17. 21 CFR 509.15 - Use of polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... environmental stability and tendency to survive and be concentrated through the food chain. The judgment as to... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Use of polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials. 509.15 Section 509.15 Food and Drugs FOOD AND DRUG...

  18. 21 CFR 109.15 - Use of polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... environmental stability and tendency to survive and be concentrated through the food chain. The judgment as to... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Use of polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials. 109.15 Section 109.15 Food and Drugs FOOD AND DRUG...

  19. 21 CFR 509.15 - Use of polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... environmental stability and tendency to survive and be concentrated through the food chain. The judgment as to... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Use of polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials. 509.15 Section 509.15 Food and Drugs FOOD AND DRUG...

  20. 21 CFR 500.45 - Use of polychlorinated biphenyls (PCB's) in the production, handling, and storage of animal feed.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... its environmental stability and tendency to survive and be concentrated through the food chain. The... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Use of polychlorinated biphenyls (PCB's) in the production, handling, and storage of animal feed. 500.45 Section 500.45 Food and Drugs FOOD AND DRUG...

  1. 21 CFR 509.15 - Use of polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... environmental stability and tendency to survive and be concentrated through the food chain. The judgment as to... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Use of polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials. 509.15 Section 509.15 Food and Drugs FOOD AND DRUG...

  2. 21 CFR 509.15 - Use of polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... environmental stability and tendency to survive and be concentrated through the food chain. The judgment as to... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Use of polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials. 509.15 Section 509.15 Food and Drugs FOOD AND DRUG...

  3. 21 CFR 109.15 - Use of polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... environmental stability and tendency to survive and be concentrated through the food chain. The judgment as to... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Use of polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials. 109.15 Section 109.15 Food and Drugs FOOD AND DRUG...

  4. 21 CFR 109.15 - Use of polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... environmental stability and tendency to survive and be concentrated through the food chain. The judgment as to... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Use of polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials. 109.15 Section 109.15 Food and Drugs FOOD AND DRUG...

  5. 21 CFR 109.15 - Use of polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... environmental stability and tendency to survive and be concentrated through the food chain. The judgment as to... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Use of polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials. 109.15 Section 109.15 Food and Drugs FOOD AND DRUG...

  6. 21 CFR 509.15 - Use of polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... environmental stability and tendency to survive and be concentrated through the food chain. The judgment as to... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Use of polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials. 509.15 Section 509.15 Food and Drugs FOOD AND DRUG...

  7. 21 CFR 500.45 - Use of polychlorinated biphenyls (PCB's) in the production, handling, and storage of animal feed.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... its environmental stability and tendency to survive and be concentrated through the food chain. The... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Use of polychlorinated biphenyls (PCB's) in the production, handling, and storage of animal feed. 500.45 Section 500.45 Food and Drugs FOOD AND DRUG...

  8. 21 CFR 500.45 - Use of polychlorinated biphenyls (PCB's) in the production, handling, and storage of animal feed.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... its environmental stability and tendency to survive and be concentrated through the food chain. The... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Use of polychlorinated biphenyls (PCB's) in the production, handling, and storage of animal feed. 500.45 Section 500.45 Food and Drugs FOOD AND DRUG...

  9. 21 CFR 500.45 - Use of polychlorinated biphenyls (PCB's) in the production, handling, and storage of animal feed.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... its environmental stability and tendency to survive and be concentrated through the food chain. The... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Use of polychlorinated biphenyls (PCB's) in the production, handling, and storage of animal feed. 500.45 Section 500.45 Food and Drugs FOOD AND DRUG...

  10. Determination of levels of polychlorinated biphenyls (PCBs) present in caulk and window glazing material samples from older buildings

    EPA Science Inventory

    Levels of polychlorinated biphenyls (PCBs) in caulk and window glazing material samples from older buildings were determined, using a method developed for this purpose. This method was evaluated by analyzing a combination of 47 samples of caulk, glazing materials, including quali...

  11. Framework for Application of the Toxicity Equivalence Methodology for Polychlorinated Dioxins, Furans, and Biphenyls in Ecological Risk Assessment (Final)

    EPA Science Inventory

    Polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and biphenyls (PCBs) are persistent contaminants found widely in the environment. Several of these compounds bioaccumulate in the tissues of fish, birds, and mammals and have been shown to cause mortality and adver...

  12. The Relationship between Prenatal and Postnatal Exposure to Polychlorinated Biphenyls (PCBs) and Cognitive, Neuropsychological, and Behavioral Deficits: A Critical Appraisal

    ERIC Educational Resources Information Center

    Cicchetti, Domenic V.; Kaufman, Alan S.; Sparrow, Sara S.

    2004-01-01

    Our purpose in this report is to evaluate scientifically that body of literature relating the effects of prenatal and postnatal exposure to polychlorinated biphenyls (PCBs) upon neurobehavioral, health-related, and cognitive deficits in neonates, developing infants, children, and adults. The data derive from seven cohorts: six cohorts of mothers…

  13. SEQUENCE SIMILARITIES IN THE GENES ENCODING POLY- CHLORINATED BIPHENYL DEGRADATION BY PSEUDOMONAS STRAIN LB400 AND ALCALIGENES EUTROPHUS H850

    EPA Science Inventory

    DNA-DNA hybridization was used to compare the Pseudomonas strain LB400 genes for polychlorinated biphenyl (PCB) degradation with those from seven other PCB-degrading strains. Significant hybridization was detected to the genome of Alcaligenes eutrophus H850, a strain similar to L...

  14. USE OF PLANT AND EARTHWORM BIOASSAYS TO EVALUATE REMEDIATION OF SOIL FROM A SITE CONTAMINATED WITH POLYCHLORINATED BIPHENYLS

    EPA Science Inventory

    Soil from a site heavily contaminated with polychlorinated biphenyls (PCBs) was treated with a pilot-scale, solvent extraction technology. Bioassays in earthworms and plants were used to examine the efficacy of the remediation process for reducing the toxicity of the soil. The ...

  15. USE OF PLANT AND EARTHWORM BIOASSYS TO EVALUATE REMEDIATION OF SOIL FROM A SITE CONTAMINATED WITH POLYCHLORINATED BIPHENYLS

    EPA Science Inventory

    Soil from a site heavily contaminated with polychlorinated biphenyls (PCBs) was treated with a pilot-scale, solvent extraction tehnology. Bioassays in earthworms and plants were used to examine the efficacy of the remediation process for reducing the toxicity of the soil. The ear...

  16. Determination of selected polychlorinated biphenyls in soil and earthworm (Eisenia fetida) using a QuEChERS-based method and gas chromatography with tandem MS.

    PubMed

    He, Zeying; Wang, Lu; Peng, Yi; Luo, Ming; Wang, Wenwen; Liu, Xiaowei

    2015-11-01

    Soil and earthworms are important objects in soil pollution assessment and environmental behavior and toxicity study for polychlorinated biphenyls. Accelerated solvent extraction and solid-phase extraction are generally required for the extraction and clean-up of polychlorinated biphenyls in soil and earthworm, which are tedious and time-consuming. In this work, a modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) procedure combined with gas chromatography and triple quadrupole mass spectrometry was developed for the determination of 20 selected polychlorinated biphenyl congeners in soil and earthworm. Different extraction times, solvents, and clean-up adsorbents were compared and optimized. The average recoveries from spiked soils ranged between 70 and 120% with satisfactory relative standard deviations for all the polychlorinated biphenyls. In earthworm, the recoveries of polychlorinated biphenyls 180, 183, and 189 were relatively low (< 70% in some spiking levels) compared to that of the other polychlorinated biphenyls. The limits of quantification were in the range of 0.01-0.05 ng/g. The method was successfully applied to the analysis of 66 agricultural soils. To our knowledge, a combined method based on QuEChERS for the determination of polychlorinated biphenyls in soil and earthworms has not been published before. The procedure proved to be simple, sensitive, efficient, and environmentally friendly.

  17. Identification of the bphA4 gene encoding ferredoxin reductase involved in biphenyl and polychlorinated biphenyl degradation in Pseudomonas sp. strain KKS102.

    PubMed Central

    Kikuchi, Y; Nagata, Y; Hinata, M; Kimbara, K; Fukuda, M; Yano, K; Takagi, M

    1994-01-01

    The nucleotide sequence of the downstream region of the bph operon from Pseudomonas sp. strain KKS102 was determined. Two open reading frames (ORF1 and ORF2) were found in this region, and the deduced amino acid sequence of ORF2 showed homology with the sequences of four ferredoxin reductases of dioxygenase systems. When this region was inserted just upstream of the bph operon, which does not contain a gene encoding ferredoxin reductase, biphenyl dioxygenase activity was detected. The 24- and 44-kDa polypeptides predicted from the two open reading frames were identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Crude extract which contained the products of ORF2 and bphA1A2A3 showed cytochrome c reduction activity. These data clearly suggest that ORF2 encodes ferredoxin reductase. The deduced amino acid sequence of ORF1 does not show significant homology with the sequences of any other proteins in the SWISS-PROT data bank, and the function of ORF1 is unknown. Images PMID:8132464

  18. Franck-Condon analysis of the S0 --> T1 absorption and phosphorescence spectra of biphenyl and bridged derivatives

    NASA Astrophysics Data System (ADS)

    Negri, Fabrizia; Zgierski, Marek Z.

    1992-11-01

    The equilibrium geometry and the vibrational force field of the ground and the lowest triplet electronic states of biphenyl and three bridged derivatives-biphenylene, fluorene and phenanthrene-are computed by using an updated version of the QCFF/PI (Quantum Chemical Force Field/π electron) Hamiltonian. The displacement parameters between T1 and S0 are obtained and used to model the S0→T1 absorption and the phosphorescence spectra. The calculated Franck-Condon envelopes are found to be in excellent agreement with the vibrational structure of the observed spectra. The common features of the phosphorescence spectra of biphenyl and fluorene are related to the same orbital nature of the lowest triplet state. The observed asymmetry between the phosphorescence and singlet-triplet absorption spectra of biphenyl is reproduced when the twisted equilibrium geometry of S0 is considered. It is shown that evidence of the nonplanarity of the ground state of biphenyl is manifested by the lower intensity of the band observed in the phosphorescence at 747 cm-1 with respect to the intensity of the same band in fluorene. The increased vibrational activity calculated in the lower frequency region for biphenylene and phenanthrene agrees with the observed spectra and reflects the different orbital nature of the lowest triplet state of the two strongly perturbed bridged derivatives with respect to biphenyl and fluorene. From the analysis of the computed vibrational frequencies, it is suggested that the false origin of the symmetry forbidden phosphorescence of biphenylene is due to the lowest out-of-plane mode of au symmetry.

  19. Structural insight into the expanded PCB-degrading abilities of a biphenyl dioxygenase obtained by directed evolution.

    PubMed

    Kumar, Pravindra; Mohammadi, Mahmood; Viger, Jean-François; Barriault, Diane; Gomez-Gil, Leticia; Eltis, Lindsay D; Bolin, Jeffrey T; Sylvestre, Michel

    2011-01-14

    The biphenyl dioxygenase of Burkholderia xenovorans LB400 is a multicomponent Rieske-type oxygenase that catalyzes the dihydroxylation of biphenyl and many polychlorinated biphenyls (PCBs). The structural bases for the substrate specificity of the enzyme's oxygenase component (BphAE(LB400)) are largely unknown. BphAE(p4), a variant previously obtained through directed evolution, transforms several chlorobiphenyls, including 2,6-dichlorobiphenyl, more efficiently than BphAE(LB400), yet differs from the parent oxygenase at only two positions: T335A/F336M. Here, we compare the structures of BphAE(LB400) and BphAE(p4) and examine the biochemical properties of two BphAE(LB400) variants with single substitutions, T335A or F336M. Our data show that residue 336 contacts the biphenyl and influences the regiospecificity of the reaction, but does not enhance the enzyme's reactivity toward 2,6-dichlorobiphenyl. By contrast, residue 335 does not contact biphenyl but contributes significantly to expansion of the enzyme's substrate range. Crystal structures indicate that Thr335 imposes constraints through hydrogen bonds and nonbonded contacts to the segment from Val320 to Gln322. These contacts are lost when Thr is replaced by Ala, relieving intramolecular constraints and allowing for significant movement of this segment during binding of 2,6-dichlorobiphenyl, which increases the space available to accommodate the doubly ortho-chlorinated congener 2,6-dichlorobiphenyl. This study provides important insight about how Rieske-type oxygenases can expand substrate range through mutations that increase the plasticity and/or mobility of protein segments lining the catalytic cavity.

  20. Bis(cyclopentadienyl)titanium complexes of naphthalene-1,8-dithiolates, biphenyl 2,2'-dithiolates, and related ligands.

    PubMed

    Aucott, Stephen M; Kilian, Petr; Milton, Heather L; Robertson, Stuart D; Slawin, Alexandra M Z; Woollins, J Derek

    2005-04-18

    Titanocene 1,8-dithiolato-naphthalene and titanocene 2,2'-dithiolato biphenyl are produced by the reaction of naphtho[1,8-cd]-1,2-dithiole [or the biphenyl] with titanocene dicarbonyl (Ti(II)) in toluene at room temperature. The pro-ligands 2,7-di(tert-butyl)naphtho[1,8-cd]-1,2-dithiole, 5,6-dihydroacenaphtho[5,6-cd]-1,2-dithiole, 4,5-dithioacephenanthrylene, and 13,14-dithiapicene have been used in similar reactions with titanocene dicarbonyl to investigate the effect of steric bulk and of varying the naphthalene backbone on the final complex. The resulting Cp(2)TiS(2)Ar complexes (Ar = naphthalene) have been shown by temperature-dependent (1)H NMR spectroscopy to exist in solution in an envelope conformation with the six-membered TiS(2)C(3) rings undergoing inversion on the NMR time scale while the similar Cp(2)TiS(2)Ar complexes (Ar = biphenyl, binaphthalene) interconvert more rapidly. Titanocene 2,2'-disulfinato biphenyl has been synthesized by the salt elimination reaction of titanocene dichloride (Ti(IV)) and the disodium salt of biphenyl 2,2'-disulfinic acid. Finally, the effect of using pro-ligands where the sulfur atoms have been mono- or di-oxidized has been studied, and an interesting oxygen elimination reaction is observed for the S=O fragments but not for the SO(2) groups. All complexes have been characterized spectroscopically and seven X-ray structures are reported.

  1. Biphenyl 4-Hydroxylases Involved in Aucuparin Biosynthesis in Rowan and Apple Are Cytochrome P450 736A Proteins1[OPEN

    PubMed Central

    Kaufholdt, David; Broggini, Giovanni A.L.; Flachowsky, Henryk; Hänsch, Robert

    2015-01-01

    Upon pathogen attack, fruit trees such as apple (Malus spp.) and pear (Pyrus spp.) accumulate biphenyl and dibenzofuran phytoalexins, with aucuparin as a major biphenyl compound. 4-Hydroxylation of the biphenyl scaffold, formed by biphenyl synthase (BIS), is catalyzed by a cytochrome P450 (CYP). The biphenyl 4-hydroxylase (B4H) coding sequence of rowan (Sorbus aucuparia) was isolated and functionally expressed in yeast (Saccharomyces cerevisiae). SaB4H was named CYP736A107. No catalytic function of CYP736 was known previously. SaB4H exhibited absolute specificity for 3-hydroxy-5-methoxybiphenyl. In rowan cell cultures treated with elicitor from the scab fungus, transient increases in the SaB4H, SaBIS, and phenylalanine ammonia lyase transcript levels preceded phytoalexin accumulation. Transient expression of a carboxyl-terminal reporter gene construct directed SaB4H to the endoplasmic reticulum. A construct lacking the amino-terminal leader and transmembrane domain caused cytoplasmic localization. Functional B4H coding sequences were also isolated from two apple (Malus × domestica) cultivars. The MdB4Hs were named CYP736A163. When stems of cv Golden Delicious were infected with the fire blight bacterium, highest MdB4H transcript levels were observed in the transition zone. In a phylogenetic tree, the three B4Hs were closest to coniferaldehyde 5-hydroxylases involved in lignin biosynthesis, suggesting a common ancestor. Coniferaldehyde and related compounds were not converted by SaB4H. PMID:25862456

  2. Biphenyl based stationary phases for improved selectivity in complex steroid assays.

    PubMed

    Lindner, Johanna M; Vogeser, Michael; Grimm, Stefanie H

    2017-08-05

    The measurement of steroid hormones and their corticoid precursors is an important aspect in endocrinology since these analytes are biomarkers for several endocrine disorders. Over the last few years, HPLC-MS/MS has become the method of choice to analyze these compounds. There are already several methods using stationary phases modified with C18 groups. However, since these columns sometimes do not enable sufficient separation of some isobaric steroids, we investigated the potential of a different RP modification using biphenyl groups for the separation of challenging isobars such as corticosterone, 11- and 21-deoxycortisol. The aim of our work was the development of an isotope dilution UHPLC-MS/MS assay for clinical research that combines simple and effective sample preparation with a powerful MS method quantifying a broad steroid panel (aldosterone, corticosterone, cortisol, cortisone, 11-deoxycorticosterone, 11-deoxycortisol, 21-deoxycortisol, dehydroepiandrosterone, dehydroepiandrosterone sulfate, 17-OH-progesterone, progesterone, and testosterone) in human serum. After a manual protein precipitation step using zinc trifluoroacetate (ZnTFA) in methanol, the supernatants were directly injected into the UHPLC-MS system. Chromatographic baseline separation of all isobaric compounds (corticosterone↔11-deoxycortisol↔21-deoxycortisol, 17-OH-progesterone↔11-deoxycorticosterone, and aldosterone↔cortisone) was achieved using a Kinetex Biphenyl column (150×2.1mm, 1.7μm) with a mobile phase consisting of 0.2mM ammonium fluoride in water and methanol. The total run time was 10min. For detection we used a Xevo TQ-S mass spectrometer operating in the ESI positive and negative modes. The method was validated according to the EMA guideline for bioanalytical method validation. The results for accuracy (within-run: 92.3%-115%, between-run: 92.4 %-113%) and imprecision (within-run: 0.80%-9.05%, between-run: 1.98 %-15.2%) were satisfying. The recovery ranged from 95% to

  3. Bioaugmentation of a historically contaminated soil by polychlorinated biphenyls with Lentinus tigrinus

    PubMed Central

    2012-01-01

    Background Several species belonging to the ecological group of white-rot basidiomycetes are able to bring about the remediation of matrices contaminated by a large variety of anthropic organic pollutants. Among them, polychlorobiphenyls (PCBs) are characterized by a high recalcitrance due to both their low bioavailability and the inability of natural microbial communities to degrade them at significant rates and extents. Objective of this study was to assess the impact of a maize stalk-immobilized Lentinus tigrinus CBS 577.79 inoculant combined with soybean oil (SO), as a possible PCB-mobilizing agent, on the bioremediation and resident microbiota of an actual Aroclor 1260 historically contaminated soil under unsaturated solid-phase conditions. Results Best overall PCB depletions (33.6 ± 0.3%) and dechlorination (23.2 ± 1.3%) were found after 60 d incubation in the absence of SO where, however, the fungus appeared to exert adverse effects on both the growth of biphenyl- and chlorobenzoate-degrading bacteria and the abundance of genes coding for both biphenyl dioxygenase (bph) and catechol-2,3-dioxygenase. A significant (P < 0.001) linear inverse relationship between depletion yields and degree of chlorination was observed in both augmented and control microcosms in the absence of SO; conversely, this negative correlation was not evident in SO-amended microcosms where the additive inhibited the biodegradation of low chlorinated congeners. The presence of SO, in fact, resulted in lower abundances of both biphenyl-degrading bacteria and bph. Conclusions The PCB depletion extents obtained in the presence of L. tigrinus are by far higher than those reported in other remediation studies conducted under unsaturated solid phase conditions on actual site soils historically contaminated by Aroclor 1260. These results suggest that the bioaugmentation strategy with the maize stalk-immobilized mycelium of this species might be promising in the reclamation of PCB

  4. Cutaneous effects of exposure to polybrominated biphenyls (PBBs): the Michigan PBB incident

    SciTech Connect

    Chanda, J.J.; Anderson, H.A.; Glamb, R.W.; Lomatch, D.L.; Wolff, M.S.; Voorhees, J.J.; Selikoff, I.J.

    1982-10-01

    In 1973 an environmental accident occurred in northern Michigan in which 1000-2000 pounds of the toxic fire retardant polybrominated biphenyl (PBB) was added to the livestock food supply of much of northern Michigan. PBB is highly lipophilic, poorly metabolized, and biocumulative. It subsequently entered the human food chain of the entire state of Michigan. Health effects were noted in contaminated animals and among exposed farmers some months after the contamination; these often included cutaneous problems. Three years later a multidisciplinary study of the farming population was undertaken. Detected cutaneous abnormalities included halogen acne, hair loss, skin redness, skin peeling, and scaling, itching, increased sweating, and increased growth of fingernails and toenails. The mechanisms underlying these effects are unknown. PBBs appear to be etiologically implicated for significant cutaneous toxicity.

  5. Domain structure in biphenyl incommensurate phase II observed by electron paramagnetic resonance

    NASA Astrophysics Data System (ADS)

    Véron, A.; Emery, J.; Spiesser, M.

    1994-11-01

    The domain structure in incommensurate phase II of single biphenyl crystal has been observed by investigations of the optically excited states of the Electronic Paramagnetic Resonance (E.P.R.) deuterated naphthalene molecular probes which substitute biphenyl molecules. Our results confirm that this phase is a 1q bi-domain one. The analysis of the spectra obtained in X band (9.5 GHz) experiments, in relation with the spin Hamiltonian parameter properties permits us to show that the E.P.R. probe rotates around a direction perpendicular to its long axis while the biphenyl molecule undergoes a twist movement around this axis. They also account for a regime which is like a “ multi-soliton " regime while the modulation is a plane wave one in the pure single crystal. The two molecules of the high temperature cell do not exactly experience the saure displacement field in the incommensurate phase and consequently the two domains can be distinguished. The spin Hamiltonian parameters which characterize the E.P.R. probes have been determined in the incommensurate phase II of biphenyl. La structure en domaines de la phase II du biphényle est mise en évidence par les investigations dans les états photo-excités des molécules de naphtalène deutéré, utilisées comme sondes de Résonance Paramagnétique Electronique, se substituant de manière diluée dans le mono-cristal de biphényle. Ceci confirme que cette phase est 1q bi-domaine. L'analyse des spectres obtenus dans des expériences en bande X (9.5 GHz) en relation avec les propriétés de l'hamiltonien de spin permet de montrer que la sonde moléculaire tourne autour d'une direction perpendiculaire à son grand axe alors que la molécule de biphényle subit un mouvement de twist autour de cet axe. Les résultats montrent que ces sondes rendent compte d'un régime qui est comme un régime “ multi-solitons " alors que la modulation est plane dans le cristal pur. Les deux molécules sondes de la cellule

  6. Digestive tract absorption of polychlorinated dibenzo-p-dioxins, dibenzofurans, and biphenyls in a nursing infant

    SciTech Connect

    McLachlan, M.S. )

    1993-11-01

    The digestive tract absorption of environmental contaminants is an important but poorly understood parameter in contaminant is an important but poorly understood parameter in contaminant risk assessments. The net absorption of polychlorinated dibenzo-p-dioxins, dibenzofurans, and biphenyls in a nursing infant was measured under natural conditions over 12 days. The levels of the substances in the mother's milk were typical for Germany. It was found that for almost all congeners over 90% of the ingested compound was absorbed. This indicates that the common assumption of 100% absorption in nursing infants is reasonable. No firm conclusions could be drawn regarding the absorption of Cl7- and Cl8DD/F due to high blank levels in the cotton diapers used.

  7. Effects of polychlorinated biphenyls, hexachlorocyclohexanes, and mercury on human neutrophil apoptosis, actin cytoskelton, and oxidative state

    USGS Publications Warehouse

    Sweet, L.I.; Passino-Reader, D. R.; Meier, P.G.; Omann, G.M.

    2006-01-01

    Apoptosis, or programmed cell death, has been proposed as a biomarker for environmental contaminant effects. In this work, we test the hypothesis that in vitro assays of apoptosis are sensitive indicators of immunological effects of polychlorinated biphenyls, hexachlorocyclohexanes, and mercury on human neutrophils. Apoptosis, necrosis, and viability as well as the related indicators F-actin levels, and active thiol state were measured in purified human neutrophils after treatment with contaminants. Effective concentrations observed were 0.3 μM (60 μg/L) mercury, 750 μg/L Aroclor 1254, and 50 μM (14,500 μg/L) hexachlorocylcohexanes. Concentrations of contaminants that induced apoptosis also decreased cellular F-actin levels. Active thiols were altered by mercury, but not organochlorines. Comparison of these data with levels of contaminants reported to be threats to human health indicate neutrophil apoptosis is a sensitive indicator of mercury toxicity.

  8. Polychlorinated biphenyl congeners in sediment cores from the Upper Mississippi River

    PubMed Central

    Martinez, Andres; Schnoebelen, Douglas J.; Hornbuckle, Keri C.

    2015-01-01

    We determined polychlorinated biphenyls (PCBs) and radionuclide 137Cs in sediment cores from the Upper Mississippi River (UMR) and the Iowa River, Iowa, at their confluence. Vertical distribution of 137Cs indicated negligible mixing in the UMR core, while the Iowa River core showed signs of mixing. A clear 137Cs peak was found in the UMR core, which was correlated to 1963. The PCB vertical distribution in UMR core was similar to the historical trend in Aroclor production observed in Great Lakes cores, with a peak close to the 137Cs peak, suggesting a date near 1960. In general, PCB congener profiles in both cores resembled the Iowa soil background signal. We concluded that despite evidence of mixing in the Iowa River core, both cores retain the PCB signature of historical and regional environmental exposure. Further, our results indicate that this iconic waterway has a long history of PCBs that reflects national production and use. PMID:26547030

  9. Incubation stage and polychlorinated biphenyl (PCB) congener patterns in an altricial and precocial bird species

    USGS Publications Warehouse

    Custer, Christine M.; Custer, Thomas W.; Thyen, Stefan; Becker, Peter H.

    2014-01-01

    The composition of polychlorinated biphenyl (PCB) congeners was compared between non-incubated and embryonated eggs of tree swallows (Tachycineta bicolor) and little terns (Sterna albifrons) to determine if measurable changes in PCB congeners occurred during the embryonic period. There was no indication of changes in PCB congener patterns over the incubation period in tree swallows in 1999 and 2000 at a site with very high PCB exposure or a site with more modest PCB exposure. Additionally, congeners known to be either quickly metabolized or conserved based on experimental studies did not generally respond as predicted. Similarly, PCB congener patterns in eggs of little terns from Bottsand, Schleswig-Holstein, Germany, did not differ between non-incubated and embryonated eggs. The results from both species suggest that the stage of incubation is not an important consideration when evaluating PCB congener patterns; comparisons and assessments can be made with eggs collected at all stages of incubation.

  10. Temperature of hydrogen radio frequency plasma under dechlorination process of polychlorinated biphenyls

    SciTech Connect

    Inada, Y. Abe, K.; Kumada, A.; Hidaka, K.; Amano, K.; Itoh, K.; Oono, T.

    2014-10-27

    It has been reported that RF (radio frequency) hydrogen plasmas promote the dechlorination process of PCBs (polychlorinated biphenyls) under irradiation of MW (microwave). A relative emission intensity spectroscope system was used for single-shot imaging of two-dimensional temperature distributions of RF hydrogen plasmas generated in chemical solutions with several mixing ratios of isopropyl alcohol (IPA) and insulation oil under MW irradiation. Our experimental results showed that the plasma generation frequencies for the oil-contaminating solutions were higher than that for the pure IPA solution. In addition, the plasma temperature in the compound liquids including both oil and IPA was higher than that in the pure IPA and oil solutions. A combination of the plasma temperature measurements and plasma composition analysis indicated that the hydrogen radicals generated in a chemical solution containing the equal volumes of IPA and oil were almost the same amounts of H and H{sup +}, while those produced in the other solutions were mainly H.

  11. Effect of intrauterine PCB (polychlorinated biphenyls) exposure on visual recognition memory

    SciTech Connect

    Jacobson, S.W.; Fein, G.G.; Jacobson, J.L.; Schwartz, P.M.; Dowler, J.K.

    1985-01-01

    Adverse neonatal outcomes have been associated with intrauterine exposure to polychlorinated biphenyls (PCBs). In a follow-up study of exposed and nonexposed infants, 123 infants tested at birth were administered Fagan's test of visual recognition memory at 7 months. Two measures of prenatal PCB exposure, cord serum PCB level and maternal report of contaminated fish consumption, predicted less preference for a novel stimulus. Preference for novelty decreased in a dose-dependent fashion with increasing levels of prenatal PCB exposure. Postnatal exposure from nursing was not related to visual recognition memory. The relation between prenatal exposure and visual recognition was not mediated by the neonatal deficits, suggesting that intrauterine PCB exposure may have a delayed effect on central nervous system functioning.

  12. Growth abnormalities in the population exposed in utero and early postnatally to polychlorinated biphenyls and dibenzofurans

    SciTech Connect

    Yueliang L. Guo; Chen-Chin Hsu; Lambert, G.H.

    1995-09-01

    This article reviews the findings in children exposed to various levels of polychlorinated biphenyls (PCBs) and related compounds in utero and early postnatally. Yu-Cheng ({open_quotes}oil-disease{close_quotes}) mothers were Taiwanese women exposed to PCBs and their heat-degradation products form the ingestion of contaminated rice oil in 1979. Children of these mothers were born growth retarded, with dysmorphic physical findings, and delayed cognitive development compared with unexposed children. In this article, findings in Yu-Cheng children born between 1978 and 1985 are summarized and compared with two other well-documented cohorts of children prenatally exposed to different levels of PCBs. Results of the investigation in Yu-Cheng children will provide important information about the toxicities, health effects, and mechanisms of PCB/PCDF exposure and demonstrate that the developing human is more sensitive than the adult to the toxic effects of these chemicals. 53 refs., 2 tabs.

  13. Polychlorinated biphenyl toxicity to Japanese quail as related to degree of chlorination

    USGS Publications Warehouse

    Hill, E.F.; Heath, R.G.; Spann, J.W.; Williams, J.D.

    1974-01-01

    To learn if the percentage of chlorine in a mixture of polychlorinated biphenyls (PCB's) alone determines toxicity, Japanese quail were fed diets containing Aroelor 1248, 1254, or 1260 at levels that added equal amounts of chlorine to the feed. The experiment comprised two consecutive 5-day periods; three sublethal concentrations of chlorine were evaluated during the first period and three lethal concentrations during the second period. Evaluations utilized comparisons of mortality, time to death, weight change, and food consumption. Sublethal concentrations produced no detectable effects. Lethal concentrations with equal Chlorine showed Aroelor 1248 to be less toxic at the highest chlorine concentrations, but at lower concentrations Aroelor 1254 was more toxic than Aroclor 1260. Although chlorine percentage of a PCB is positively correlated with its avian toxicity, PCB toxicity is apparently not simply a function of chlorination.

  14. Polychlorinated biphenyls (PCBs) in a benthic ecosystem in Gwangyang Bay, South Korea.

    PubMed

    Hong, Sang Hee; Kannan, Narayanan; Yim, Un Hyuk; Choi, Jin-Woo; Shim, Won Joon

    2011-12-01

    Benthic ecosystem in Gwangyang Bay, a fast developing industrial area with steel production, port container handling, petroleum and other chemical processing in South Korea was studied. The average levels of polychlorinated biphenyls (ΣPCB) in the benthic components were: seawater 2.99 ± 0.13 (ng/L); sediment 294 ± 118 (ng/g TOC); [biota=ng/g lipid] starfish 92; prawn 131 ± 2; mussels 127 ± 22; crab 182 ± 114; clam 187; polychaeta 215; sea cucumber 497 ± 90; squill 603 ± 38; fish 396 ± 159. Levels in the inner bay samples were higher than the outer bay samples suggesting land based pollution. Good correlation (r(2)=0.79; p<0.05) existed between PCB concentration and lipid content indicating partitioning processes in action. PCB signature in the abiotic and biotic components shows enrichment of lower chlorinated congeners emitted by a unique source nearby, viz. steel manufacturing plant.

  15. Tissue concentrations of heavy metals and polychlorinated biphenyls in raccoons in central New York

    SciTech Connect

    Valentine, R.L.; Bache, C.A.; Gutenmann, W.H.; Lisk, D.J. )

    1988-06-01

    The ubiquitous presence of heavy metals such as lead, mercury and cadmium and polychlorinated biphenyls (PCBs) in wildlife animals has been studied. Possible sources of these toxicants include pesticides used agriculturally, highway traffic exhaust, landfills, power plants and miscellaneous industrial and other activities. Fish-consuming animals may also absorb heavy metals and PCBs from this dietary source. Small game hunting and the trapping of fur-bearing animals are actively pursued in Central New York and these animals are exposed to all of the latter pollution sources. It was therefore of interest to determine the concentrations of such toxicants as cadmium, lead, mercury, selenium and PCBs in wildlife animals in this area of New York State.

  16. Atmospheric polychlorinated biphenyls in Indian cities: levels, emission sources and toxicity equivalents.

    PubMed

    Chakraborty, Paromita; Zhang, Gan; Eckhardt, Sabine; Li, Jun; Breivik, Knut; Lam, Paul K S; Tanabe, Shinsuke; Jones, Kevin C

    2013-11-01

    Atmospheric concentration of Polychlorinated biphenyls (PCBs) were measured on diurnal basis by active air sampling during Dec 2006 to Feb 2007 in seven major cities from the northern (New Delhi and Agra), eastern (Kolkata), western (Mumbai and Goa) and southern (Chennai and Bangalore) parts of India. Average concentration of Σ25PCBs in the Indian atmosphere was 4460 (± 2200) pg/m(-3) with a dominance of congeners with 4-7 chlorine atoms. Model results (HYSPLIT, FLEXPART) indicate that the source areas are likely confined to local or regional proximity. Results from the FLEXPART model show that existing emission inventories cannot explain the high concentrations observed for PCB-28. Electronic waste, ship breaking activities and dumped solid waste are attributed as the possible sources of PCBs in India. Σ25PCB concentrations for each city showed significant linear correlation with Toxicity equivalence (TEQ) and Neurotoxic equivalence (NEQ) values.

  17. Novel biphenyl-substituted 1,2,4-oxadiazole ferroelectric liquid crystals: synthesis and characterization

    PubMed Central

    Subrao, Mahabaleshwara; Potukuchi, Dakshina Murthy; Sharada Ramachandra, Girish; Bhagavath, Poornima; Bhat, Sangeetha G

    2015-01-01

    Summary Two novel series of unsymmetrically substituted 1,2,4-oxadiazole viz., R.Ox.C*Cn compounds are synthesized and characterized. An optically active, (S)-(+)-methyl 3-hydroxy-2-methylpropionate is used to introduce a chiral center in the molecule. A biphenyl moiety prepared by Suzuki coupling reaction is directly attached to the oxadiazole core at C-5 position. Investigations for the phase behavior revealed that the series with a benzyl group on one end of the oxadiazole core exhibits an 1D orthogonal smectic-A phase while the second series with dodecyl flexible end chain shows orthogonal smectic-A and tilted chiral smectic-C (SmC*) phases over a wide range of temperatures. The smectic-C phase exhibits ferroelectric (FE) polarization switching. The mesomorphic thermal stabilities of these compounds are discussed in the domain of the symmetry and the flexibility of the alkyloxy end chain length attached to the chiral center. PMID:25815075

  18. [EVALUATION OF MIGRATION ABILITY OF POLYCHLORINATED BIPHENYLS IN THE "SOIL-PLANT" AND "SOIL-EARTHWORMS"].

    PubMed

    Baeva, Yu I; Chernykh, N A

    2016-01-01

    In the article there is given a hygienic assessment ofpolychlorinated biphenyls (PCBs) contamination of soils of the city of Serpukhov of the Moscow region. For the first time there was investigated the PCB's ability to migrate in the system "soil-earthworms", and were calculated bioaccumulation factors at the different level of soil contamination. There was performed a comparative evaluation of the accumulation of given contaminants by higher terrestrial plants and representatives of soil paedobionts (Lumbricidae worms), and revealed clear differences in these processes. There was shown the possibility of the use of earthworms as a highly sensitive bio-indicators in monitoring for soil contamination by persistent organic pollutants, even at low concentrations.

  19. Improved extraction procedures for polychlorinated biphenyls in solid samples with aqueous sodium hydroxide under autoclave conditions.

    PubMed

    Akimoto, Y; Inouye, Y

    2000-03-01

    The efficacy of the extraction of polychlorinated biphenyls (PCBs) from varnish-infiltrated insulating papers as a model of solid materials with an aqueous sodium hydroxide (NaOH) by autoclaving at 121 degrees C for 30 min was compared with those for the conventional procedures, i.e., saponification with 1 N ethanolic NaOH in a boiling water bath for 60 min and extraction with benzene in a Soxhlet apparatus. The newly invented autoclaving method was found to be superior to the conventional ones, yielding approximately 5- to 6-fold cumulative PCB congeners without being accompanied by extended decomposition. Therefore, the autoclave-based sample treatment is recommended for more accurate determination of PCBs in the case of PCB-impregnated solid materials such as hardened oils and resin-coated or -infiltrated papers instead of being treated conventionally.

  20. Chiral biphenyl diphosphines for asymmetric catalysis: Stereoelectronic design and industrial perspectives

    PubMed Central

    Jeulin, Séverine; de Paule, Sébastien Duprat; Ratovelomanana-Vidal, Virginie; Genêt, Jean-Pierre; Champion, Nicolas; Dellis, Philippe

    2004-01-01

    Two original chiral diphosphines, SYNPHOS and DIFLUORPHOS, have been synthesized on multigram scales. Their steric and electronic profiles have been established in comparison with the commonly used 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl and 6,6′-dimethoxy-2,2′-bis(diphenylphosphino)-1,1′-biphenyl ligands. A screening study of the four ligands in RuII-catalyzed asymmetric hydrogenation of prochiral ketones and olefins has been performed. It revealed that the stereoelectronic features of the ligand and the substrate deeply influenced the enantioselectivities obtained in asymmetric hydrogenation, SYNPHOS and DIFLUORPHOS being fully complementary in terms of enantioselectivity for this reaction. PMID:15031423

  1. Polychlorinated biphenyl pollution caused by resuspension of surface sediments in the lagoon of Venice.

    PubMed

    Raccanelli, S; Pavoni, B; Marcomini, A; Orio, A A

    1989-03-01

    A mechanical device was used to reproduce in the laboratory the sediment resuspension caused by tidal currents and wind waves in the lagoon of Venice. Shear stresses comparable to those observed in the field were applied to the sediment surface. Series of experiments were run at 6.6 and 9.0 dyn/cm2. The concentration of polychlorinated biphenyls (PCBs) were determined in the sediments and resuspended particulate matter by means of gas chromatographic techniques. At the two different stresses, particulate matter with different grain size and different concentrations of PCBs was resuspended. However, no significant differences were observed in the amounts of PCBs mobilized per litre of water. In fact, by increasing the applied stress, coarser particulate matter was resuspended with a lower concentration of PCBs per unit of dry weight.

  2. Contamination of soil, leaves and vegetables by polychlorinated biphenyls in Xiamen region, China.

    PubMed

    Maskaoui, Khalid; Zhou, Jun-Liang; Han, Ya-Li; Hu, Zhong; Zheng, Tian-Ling; Hong, Hua-Sheng

    2005-01-01

    The paper aimed to identify the primary of polychlorinated biphenyls(PCBs) in the Jiulong River Estuary, investigate the spatial distribution of PCBs contamination in the environment, localize the atmospheric source and evaluate ongoing PCBs emissions by analyzing soil samples collected along the Jiulong River region. In addition, the accumulation of PCBs in the human food chain was quantified by analyzing leaf of orange trees and vegetable samples collected along a gradient of soil/atmospheric contamination moving away from the source. Consequently, the impact on the human health and the ecosystem was quantified, different management options were proposed to reduce this impact and to carry out research on organic contaminants along the Jiulong River and Xiamen region.

  3. Polychlorinated biphenyl contamination and minisatellite DNA mutation rates of tree swallows.

    PubMed

    Stapleton, M; Dunn, P O; McCarty, J; Secord, A; Whittingham, L A

    2001-10-01

    The evidence that exposure to polychlorinated biphenyls (PCBs) leads to mutations is equivocal and controversial. Using multilocus DNA fingerprinting, we compared the mutation rate of tree swallows (Tachycineta bicolor) nesting at sites with high and low levels of contamination with PCBs. The upper Hudson River, USA, is highly contaminated with PCBs as a result of releases from two capacitor manufacturing plants in Hudson Falls and Fort Edward, New York, USA. Tree swallows nesting nearby have some of the highest known concentrations of PCBs in their tissues of any contemporary bird population (up to 114,000 ng PCB/g tissue). We found no difference in mutation rates between sites in New York with high PCB contamination and reference sites in Wisconsin, USA, and Ontario and Alberta, Canada, with known or presumably low levels of contamination. Thus, the mechanism behind altered reproductive behavior of tree swallows along the upper Hudson River is most likely physiological impairment, such as endocrine disruption, rather than mutation.

  4. Polychlorinated biphenyls in polysulfide sealants--occurrence and emission from a landfill station.

    PubMed

    Persson, N Johan; Pettersen, Harald; Ishaq, Rasha; Axelman, Johan; Bandh, Cecilia; Broman, Dag; Zebühr, Yngve; Hammar, Tommy

    2005-11-01

    Approximately 80,000 kg polysulfide sealant containing 10,000-18,000 kg polychlorinated biphenyls (PCB) was deposited at a Swedish municipal landfill station during 1965-1973. Investigations during 1994 showed that soil layers underneath the landfill had concentration of PCB not alarmingly high. The concentration of PCB congeners in ground water samples was elevated 4-750 times compared to a reference sample. Based on samples of ground water, leachate water, and flux chambers measuring evaporation of PCB from the landfill surface, the emission of PCB was estimated to be 1 g sigmaPCB/yr. This very low rate was attributed to the high sorptive capacity of the sealant. Compared to a reference site, the evaporation flux was elevated for the most volatile congeners, but factors 20-1400 lower than from another landfill which was contaminated with PCB in paper-pulp fibres.

  5. [Application prospect about bioremediation of polychlorinated biphenyls-contaminated soil with immobilized microorganism technique: a review].

    PubMed

    Hu, Jin-Xing; Su, Xiao-Mei; Han, Hui-Bo; Shen, Chao-Feng; Shi, Ji-Yan

    2014-06-01

    As one type of the persistent organic pollutants, polychlorinated biphenyls (PCBs) are tremendously harmful to organisms. These compounds are easily absorbed onto soil particles and able to accumulate in soil after they are released into the environment. Bioremediation technology of PCBs-contaminated soils has become a research hotspot in recent years, and immobilized microorganism technique has high developing and applying value because of its unique advantages in environmental remediation. This paper reviewed the chief remediation technology of PCBs-contaminated soils and then analyzed the characteristics of immobilized microorganism technique and its research progress in remediation of organic polluted soil. Finally, the feasibility and problems of this technique in remediation of PCBs-contaminated soil were also discussed.

  6. Lithium salt of biphenyl tetracarboxylate as an anode material for Li/Na-ion batteries

    NASA Astrophysics Data System (ADS)

    Medabalmi, Veerababu; Wang, Guanxiong; Ramani, Vijay K.; Ramanujam, Kothandaraman

    2017-10-01

    Electrochemical lithiation/delithiation and sodiation/desodiation studies are carried out on lithium [1,1‧-biphenyl]-3,3‧,4,4‧-tetracarboxylate (Li4-BPTC). Although four Li+ can be inserted, only two Li+ was reversible yielding a capacity of 110, 122 and 107 mAh g-1 (after 50 cycles) at a current density of 40, 80 and 160 mA g-1 respectively. As sodium analog of Li4-BPTC is unstable in the ambient conditions, Li4-BPTC was tested in sodium half-cell and a reversible capacity of 107 mAh g-1 was obtained even after 200 cycles at 160 mA g-1 rate. The exchange of Li+ by Na+ in Li4-BPTC electrode during the electrochemical sodiation/desodiation was confirmed by ICP-OES and XPS studies.

  7. Trophodynamic analysis of polychlorinated biphenyl congeners and other chlorinated hydrocarbons in the Lake Ontario ecosystem

    SciTech Connect

    Oliver, B.G.; Niimi, A.J. )

    1988-04-01

    The bioaccumulation of polychlorinated biphenyl (PCB) congeners and some other chlorinated organics in the Lake Ontario ecosystem has been studied. In addition to the classical biomagnification of PCBs and some of the other organics, the chlorine content of the PCBs was observed to increase with trophic level. Most of the differential PCB fractionation seemed to occur at the lower end of the food chain (water to plankton to mysid). At the higher trophic levels (mysid to smelt to salmonid), the PCBs seemed to be distributed as a uniform composition mixture. The bioaccumulation factor of these hydrophobic organics increased linearly with octanol-water partition coefficient of the chemicals at all trophic levels. The environmental bioaccumulation of these chemicals in salmonids was higher than that predicted from bioconcentration from water alone, showing that contaminated food is a major source of these chemical residues in fish.

  8. Traceless liquid-phase synthesis of biphenyls and terphenyls using pentaerythritol as a tetrapodal soluble support.

    PubMed

    Kim, Chul-Bae; Cho, Chul-Hee; Kim, Chang Keun; Park, Kwangyong

    2007-01-01

    Application of a novel sulfonate-based traceless multifunctional linker system using pentaerythritol as a tetrapodal soluble support was demonstrated using liquid-phase parallel and combinatorial preparation of biphenyl and terphenyl compounds. Nickel-catalyzed reactions of pentaerythritol tetrakis(arenesulfonate)s with arylmagnesium bromides generated the desired products in sufficient yields through reductive cleavage/cross-coupling of the C-S bond. Homogeneous pentaerythritol-supported reactions could be accomplished using less nucleophile with shorter reaction periods than could the corresponding heterogeneous polymer-supported reactions. This liquid-phase approach using a small polyfunctionalized support combines advantages of solution-phase and solid-phase syntheses by allowing high reactivity, high atom economy, simple isolation, and real-time monitoring of the reaction progress.

  9. Accumulation of polychlorinated biphenyls in turbot (Scophthalmus maximus) from seawater sediments and food

    NASA Astrophysics Data System (ADS)

    Courtney, W. A. M.; Langston, W. J.

    1980-03-01

    Juvenile turbot, Scophthalmus maximus (L.), were exposed to 0.58 µg 1-1 Aroclor 1254 in seawater, to sediments containing 100, 60 and 1 ppm or fed with cockle containing 20 ppm PCB (polychlorinated biphenyls). Concentration factors for liver and muscle were 104 and 103, respectively, for uptake of PCB from seawater. Contamination of muscle was similar to that of sediments containing 1 and 60 ppm PCB to which turbot were exposed, but less than the 20 ppm in their experimental diet. Contamination of flatfish in the North Sea area is compared with the levels of PCB in the flounder, Platichthys flesus (L.), in the River Thames and predictable values for uptake of PCB from different pathways discussed.

  10. Distribution of polychlorinated biphenyls (PCBs) in surface sediments of Gable Mountain Pond

    SciTech Connect

    Riley, R.G.; Prohammer, L.A.; Neitzel, D.A.; Bean, R.M.; Thomas, J.M.

    1986-01-01

    Samples of sediments were collected and analyzed to determine the concentration and distribution of polychlorinated biphenyls (PCBs) in Gable Mountain Pond, which is located on the Hanford Site in southeastern Washington State. All samples, with one exception, were found to contain the specific PCB Aroclor 1260, a constituent of the insulating fluid used in electric utility transformers. The highest concentration of PCBs in the pond was found next to the mouth of the inlet pipe. The distribution of PCBs over the pond is consistent with the hypothesis that they entered primarily through the inlet pipe and spread along the length of the pond in a roughly westerly direction. Concentrations of Arochlor 1260 ranged from 2 to 148 parts per billion, which is roughly two to four orders of magnitude below the regulated upper concentration limit (50 parts per million) for the disposal of PCB-contaminated waste. 19 res., 8 figs., 2 tabs.

  11. Polychlorinated biphenyls in a terrestrial predator, the pine marten (Martes martes L.)

    SciTech Connect

    Bremle, G.; Larsson, P.; Helldin, J.O.

    1997-09-01

    A terrestrial predator population, the pine marten (Martes martes, L.), inhabiting an area in mid-Sweden was investigated for polychlorinated biphenyls, p,p{prime}-DDE, lindane, and hexachlorobenzene. The condition of the animals, as shown by intestine fat amounts or fat content of muscle tissue, showed negative relationships with concentration of persistent pollutants. The relationship resulted in a higher concentration of pollutants as intestinal fat amounts of muscle fat content decreased and lower levels of pollutants as these indexes of condition improved. The results indicate that terrestrial predators show changes in pollutant concentration due to condition, caused by food availability and starvation. No differences in pollutant concentration were recorded between males and females and no relationship was found for levels of pollutants and age or reproduction (females). The latter results are in contrast to those found for aquatic predatory mammals.

  12. Mesomorphic, dielectric, and optical properties of fluorosubstituted biphenyls, terphenyls, and quaterphenyls

    NASA Astrophysics Data System (ADS)

    Kula, P.; Spadło, A.; Dziaduszek, J.; Filipowicz, M.; Dąbrowski, R.; Czub, J.; Urban, S.

    2008-12-01

    Compounds with moderate and large negative dielectric anisotropy (Δɛ) are very attractive liquid crystal (LC) for vertical alignment mode (VA). Materials with such properties can be achieved by lateral substitution of a polar group into a mesogenic molecule. We synthesized some new LC materials with a negative value of Δɛ, a moderately high birefringence (Δn), and a low viscosity. The mesomorphic and physical behaviour of the novel biphenyls, terphenyls and quaterphenyls fluorosubstituted in the rigid core and also with fluorinated alkyl and alkoxy chains are investigated. The prepared series of four LC compounds are promising for new LC mixtures for various applications. Examples of nematic mixtures with Δɛ˜-3.25 will be presented.

  13. Temperature of hydrogen radio frequency plasma under dechlorination process of polychlorinated biphenyls

    NASA Astrophysics Data System (ADS)

    Inada, Y.; Abe, K.; Kumada, A.; Hidaka, K.; Amano, K.; Itoh, K.; Oono, T.

    2014-10-01

    It has been reported that RF (radio frequency) hydrogen plasmas promote the dechlorination process of PCBs (polychlorinated biphenyls) under irradiation of MW (microwave). A relative emission intensity spectroscope system was used for single-shot imaging of two-dimensional temperature distributions of RF hydrogen plasmas generated in chemical solutions with several mixing ratios of isopropyl alcohol (IPA) and insulation oil under MW irradiation. Our experimental results showed that the plasma generation frequencies for the oil-contaminating solutions were higher than that for the pure IPA solution. In addition, the plasma temperature in the compound liquids including both oil and IPA was higher than that in the pure IPA and oil solutions. A combination of the plasma temperature measurements and plasma composition analysis indicated that the hydrogen radicals generated in a chemical solution containing the equal volumes of IPA and oil were almost the same amounts of H and H+, while those produced in the other solutions were mainly H.

  14. Prediction of mutagenicity and carcinogenicity using in silico modelling: A case study of polychlorinated biphenyls.

    PubMed

    Vračko, M; Bobst, S

    2015-01-01

    In silico modelling is an important alternative method for the evaluation of properties of chemical compounds. Basically, two concepts are used in its applications: QSAR modelling for endpoint predictions, and grouping (categorization) of large groups of chemicals. In the presented report we address both of these concepts. As a case study we present the results on a set of polychlorinated biphenyls (PCBs) and some of their metabolites. Their mutagenicity and carcinogenic potency were evaluated with CAESAR and T.E.S.T. models, which are freely available over the internet. We discuss the value and reliability of the predictions, the applicability domain of models and the ability to create prioritized groupings of PCBs as a category of chemicals.

  15. Polychlorinated biphenyls removal from contaminated soils using a transportable indirect thermal dryer unit: implications for emissions.

    PubMed

    Yang, Bing; Xue, Nandong; Ding, Qiong; Vogt, Rolf David; Zhou, Lingli; Li, Fasheng; Wu, Guanglong; Zhang, Shilei; Zhou, Dandan; Liu, Bo; Yan, Yunzhong

    2014-11-01

    An assessment in China of the application of a transportable indirect thermal dryer unit for the remediation of soils contaminated with polychlorinated biphenyls (PCBs) demonstrated that it is well suited to remove PCBs from soils. A remarkable reduction of total PCBs in soils from 163-770 μg g(-1) to 0.08-0.15 μg g(-1) was achieved. This represented removal efficiencies of greater than 99.9% and an approximate 100% removal of the toxic equivalent of the PCBs. Furthermore, the emissions to the atmosphere from the unit were in compliance with current PCBs regulations. In conclusion, remediation of PCBs-contaminated soils based on a transportable indirect thermal dryer unit appears to be a highly efficient and environmentally sound treatment technology that has huge implications for cleaning thousands of regionally dispersed sites of PCBs contamination in China.

  16. QSAR studies of bioconcentration factors of polychlorinated biphenyls (PCBs) using DFT, PCS and CoMFA.

    PubMed

    Liu, Hui; Liu, Hongxia; Sun, Ping; Wang, Zunyao

    2014-11-01

    The bioconcentration factors (BCFs) of 58 polychlorinated biphenyls (PCBs) were modeled by quantitative structure-activity relationship (QSAR) using density functional theory (DFT), the position of Cl substitution (PCS) and comparative molecular field analysis (CoMFA) methods. All the models were robust and predictive, and especially, the best CoMFA model was significant with a correlation coefficient (R(2)) of 0.926, a cross-validation correlation coefficient (Q(2)) of 0.821 and a root mean square error estimated (RMSE) of 0.235. The results indicate that the electrostatic descriptors play a more significant role in BCFs of PCBs. Additionally, a test set was used to compare the predictive ability of our models to others, and results show that our CoMFA model present the lowest RMSE. Thus, the models obtain in this work can be used to predict the BCFs of remaining 152 PCBs without available experimental values.

  17. Alteration of Rat Fetal Cerebral Cortex Development after Prenatal Exposure to Polychlorinated Biphenyls

    PubMed Central

    Naveau, Elise; Pinson, Anneline; Gérard, Arlette; Nguyen, Laurent; Charlier, Corinne; Thomé, Jean-Pierre; Zoeller, R. Thomas; Bourguignon, Jean-Pierre; Parent, Anne-Simone

    2014-01-01

    Polychlorinated biphenyls (PCBs) are environmental contaminants that persist in environment and human tissues. Perinatal exposure to these endocrine disruptors causes cognitive deficits and learning disabilities in children. These effects may involve their ability to interfere with thyroid hormone (TH) action. We tested the hypothesis that developmental exposure to PCBs can concomitantly alter TH levels and TH-regulated events during cerebral cortex development: progenitor proliferation, cell cycle exit and neuron migration. Pregnant rats exposed to the commercial PCB mixture Aroclor 1254 ended gestation with reduced total and free serum thyroxine levels. Exposure to Aroclor 1254 increased cell cycle exit of the neuronal progenitors and delayed radial neuronal migration in the fetal cortex. Progenitor cell proliferation, cell death and differentiation rate were not altered by prenatal exposure to PCBs. Given that PCBs remain ubiquitous, though diminishing, contaminants in human systems, it is important that we further understand their deleterious effects in the brain. PMID:24642964

  18. Alteration of rat fetal cerebral cortex development after prenatal exposure to polychlorinated biphenyls.

    PubMed

    Naveau, Elise; Pinson, Anneline; Gérard, Arlette; Nguyen, Laurent; Charlier, Corinne; Thomé, Jean-Pierre; Zoeller, R Thomas; Bourguignon, Jean-Pierre; Parent, Anne-Simone

    2014-01-01

    Polychlorinated biphenyls (PCBs) are environmental contaminants that persist in environment and human tissues. Perinatal exposure to these endocrine disruptors causes cognitive deficits and learning disabilities in children. These effects may involve their ability to interfere with thyroid hormone (TH) action. We tested the hypothesis that developmental exposure to PCBs can concomitantly alter TH levels and TH-regulated events during cerebral cortex development: progenitor proliferation, cell cycle exit and neuron migration. Pregnant rats exposed to the commercial PCB mixture Aroclor 1254 ended gestation with reduced total and free serum thyroxine levels. Exposure to Aroclor 1254 increased cell cycle exit of the neuronal progenitors and delayed radial neuronal migration in the fetal cortex. Progenitor cell proliferation, cell death and differentiation rate were not altered by prenatal exposure to PCBs. Given that PCBs remain ubiquitous, though diminishing, contaminants in human systems, it is important that we further understand their deleterious effects in the brain.

  19. Temperature dependence of aqueous solubility of selected chlorobenzenes, polychlorinated biphenyls, and dibenzofuran

    SciTech Connect

    Shiu, W.Y.; Wania, F.; Hung, H.; Mackay, D.

    1997-03-01

    The aqueous solubilities of seven chlorobenzenes (1,4-dichlorobenzene, 1,2,3-trichlorobenzene, 1,3,5-trichlorobenzene, 1,2,3,5-tetrachlorobenzene, 1,2,4,5-tetrachlorobenzene, pentachlorobenzene, and hexachlorobenzene), five polychlorinated biphenyls (4-chlorobiphenyl, 4,4{prime}-dichlorobiphenyl, 2,4,5-trichlorobiphenyl, 2,3,4,5-tetrachlorobiphenyl, and 2,2{prime},4,4{prime},6,6{prime}-hexachlorobiphenyl), and dibenzofuran are reported over the range 5 to 45 C, from which enthalpies of solution are deduced. The octanol-water partition coefficient (K{sub OW}) of dibenzofuran deduced from its solubilities in octanol, in octanol saturated with water, and in water saturated with octanol is also reported for the same range in temperature, showing agreement with the previously reported value of K{sub OW} and much less sensitivity to temperature.

  20. Residues of polychlorinated biphenyls (PCBs) in fish, water and sediment from Shing Mun River

    SciTech Connect

    Chui, V.W.; Lam-Leung, S.Y.; Chan, T.C. )

    1991-12-01

    The level and pattern of contamination by polychlorinated biphenyls (PCBs) were investigated in tilapia, Oreochromis mossambicus (Peters), sediment, and water from the Shing Mun River. The range of total PCBs was 12.9 ng/g to 181.6 ng/g wet weight in tilapia, 12.7 ng/g to 46.0 ng/g freeze-dried weight in sediment, and 3.8 ng/L to 13.6 ng/L in water. The effect of biomagnification was also observed, PCB concentrations increased from water to sediment to tilapia. PCB congeners occurred in such a way that lower chlorinated PCBs comprised a higher fraction of the total PCBs in water, sediment, and tilapia muscle, whereas higher chlorinated PCBs were more commonly found only in tilapia.