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. POLYCHLORINATED BIPHENYLS: PROGRESS AND PROBLEMS

    EPA Science Inventory

    Polychlorinated biphenyls (PCBs) are industrial chemical products which are synthesized by the direct chlorination of biphenyl. he degree of biphenyl ring chlorination determines the physical properties and applications of commercial PCBs and, therefore, it is not surprising that...

  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. 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.

  6. 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

  7. 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. PMID:12117297

  8. Nonoccupational exposure to polychlorinated biphenyls

    SciTech Connect

    Thurston, F.E.

    1988-01-01

    Polychlorinated biphenyls became worldwide environmental contaminants during five decades of industrial use. They cause cancer in some animals and are suspected of causing birth defects and elevated triglycerides in humans. The risk to humans from low-level exposure is unclear. No clinical symptoms have yet been identified in people who eat contaminated fish, a major source of low-level exposure. 19 references.

  9. 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.

  10. Polychlorinated biphenyls in tree bark

    SciTech Connect

    Hermanson, M.H.; Hites, R.A. )

    1990-05-01

    Polychlorinated biphenyl (PCB) concentrations in tree bark vary with proximity to a source. Higher total PCB bark/air ratios in areas near contamination show that bark may retain PCB from prior periods of high atmospheric concentrations. Bark is enriched in the more chlorinated PCB homologues relative to air. Congener-specific analyses show that, when compared with air, bark favorably accumulates the less volatile congeners. Lipophilicity is not a good indicator of bark PCB concentrations, but vapor pressure is.

  11. 40 CFR 721.1790 - Polybrominated biphenyls.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... reporting. (1) The chemical substances identified as 1,1′-(Biphenyl, 4,4′-dibromo- (CAS No. 92-86-4); 1,1′-(Biphenyl, 2-bromo- (CAS No. 2052-07-5); 1,1′-(Biphenyl, 3-bromo- (CAS No. 2113-57-7); 1,1′-(Biphenyl, 2,2′, 3,3′, 4,4′, 5,5′, 6,6′-decabromo- (CAS No. 13654-09-6); Nonabromobiphenyl (CAS No....

  12. 40 CFR 721.1790 - Polybrominated biphenyls.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... reporting. (1) The chemical substances identified as 1,1′-(Biphenyl, 4,4′-dibromo- (CAS No. 92-86-4); 1,1′-(Biphenyl, 2-bromo- (CAS No. 2052-07-5); 1,1′-(Biphenyl, 3-bromo- (CAS No. 2113-57-7); 1,1′-(Biphenyl, 2,2′, 3,3′, 4,4′, 5,5′, 6,6′-decabromo- (CAS No. 13654-09-6); Nonabromobiphenyl (CAS No....

  13. Kinetics of biphenyl and polychlorinated biphenyl metabolism in soil

    SciTech Connect

    Focht, D.D.; Brunner, W.

    1985-10-01

    The metabolism of /sup 14/C-labeled PCBs (polychlorinated biphenyls), which comprised the Aroclor 1242 mixture, was greatly enhanced by the addition of biphenyl (BP) to soil. After 49 days, only 25 to 35% of the original PCBs remained in the soil, and 48 to 49% was converted to /sup 14/CO/sub 2/ (including soil carbonates) in treatment enriched with BP; by contrast, 92% of the PCBs remained and less than 2% was converted to /sup 14/CO/sub 2/ in the unenriched control. Although the mineralization of PCBs in soils inoculated with Acinetobacter strain P6 was not greater than that in uninoculated BP-enriched soils, the initial and maximum mineralization rates and mineralization of BP was consistent with kinetic models based upon linear-no growth and exponential growth; lower cell densities (< 10/sup 6//g) of BP-oxidizing bacteria gave a better fit for exponential growth, whereas the highest cell density (10/sup 9//g) gave a better fit for linear-no growth. The numbers of BP-oxidizing bacteria declined exponentially upon depletion of the substrate. Since the mineralization of the chlorinated cometabolites was brought about by microorganisms (comensals) other than BP oxidizers, /sup 14/CO/sub 2/ production could not be fit to either of the two growth models. However, /sup 14/CO/sub 2/ production from the highest-density inoculum could be fit to a first-order (no-growth) sequential-reaction series.

  14. 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

  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. POLYCHLORINATED BIPHENYLS AS HORMONALLY ACTIVE STRUCTURAL ANALOGUES

    EPA Science Inventory

    Among the environmental chemicals believed to have the potential to disrupt the endocrine systems of animals including humans, the polychlorinated biphenyls are a chemical class of considerable concern. Possible mechanisms by which these chemicals may interfere with endocrine fun...

  17. USE OF THE 'ORTHO EFFECT' FOR CHLORINATED BIPHENYL AND BROMINATED BIPHENYL ISOMER IDENTIFICATION

    EPA Science Inventory

    The ortho effect observed for chlorinated biphenyls (PCBs) and brominated biphenyls (PBBs) having 2,2; 2,2', 6 or 2,2', 6,6' halogens, can be combined with GC retention index for isomer specific identifications by gas chromatography/mass spectrometry (GC/MS). This technique relia...

  18. Polychlorinated biphenyls inventory in Belarus.

    PubMed

    Kukharchyk, Tamara I; Kakareka, Sergey V

    2008-09-01

    Polychlorinated biphenyls (PCB) inventory is a key element of the ecologically sound management of these dangerous chemicals. This article presents the findings of the large-scale PCB inventory project that was implemented in Belarus in 2003-2004. Data on PCB-containing equipment of more than 2000 enterprises was recorded: trademarks; volumes of PCBs; dates of manufacture; condition of equipment; levels of operation, descriptions of installations or storage locations. In the course of the inventory about 1500 tones of PCBs were identified, 99% of this total was found in power transformers and capacitors. As it proved most equipment containing PCBs is still in service today due to its long life-time. Additionally, the PCB-containing equipment which has been taken out of service is primarily stored on the territory of enterprises. The distribution of PCBs in Belarus among economy sectors as well as regions is shown. Problems of the PCB inventory and disposal are discussed. It is shown that the inventory needs to be regularly updated in order to estimate temporal changes in PCB-containing equipment condition, current owners and a location. PMID:17597287

  19. 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.

  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. 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...

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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.

  7. 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)

  8. 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.

  9. 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.

  10. 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

  11. Enhanced degradation of polychlorinated biphenyls by directed evolution of biphenyl dioxygenase

    SciTech Connect

    Kumamaru, Tetsuya; Suenaga, Hikaru; Mitsuoka, Mariko; Watanabe, Takahito; Furukawa, Kensuke

    1998-07-01

    Biphenyl dioxygenases (BP Dox) from different organisms, which are involved in the initial oxygenation and subsequent degradation of polychlorinated biphenyls (PCB), are similar in structure but have different functions. The large subunit of BP Dox, encoded by the bphA1 gene, is crucial for substrate selectivity. Using the process of DNA shuffling, the authors randomly recombined the bphA1 genes of Pseudomonas pseudoalcaligenes KF707 and Burkholderia cepacia LB400 and selected for genes that expressed proteins with altered function. Upon expression in Escherichia coli, some of these evolved genes exhibited enhanced degradation capacity, not only for PCB and related biphenyl compounds, but for single aromatic hydrocarbons such as benzene and toluene, which are poor substrates for the original BP Dox.

  12. Bioavailability of soil-sorbed biphenyl to bacteria

    SciTech Connect

    Feng, Y.; Park, J.H.; Voice, T.C.; Boyd, S.A.

    2000-05-15

    Limited bioavailability of organic pollutants in soil may be a detriment to the successful application of bioremediation. The availability of soil-sorbed biphenyl to two biphenyl-degrading bacteria, Pseudomonas putida P106 and Rhodococcus erythropolis NY05, was assessed using a kinetic mineralization assay. Biphenyl was aged in four soils of different organic carbon (OC) contents for up to 274 days. With a biphenyl-soil contact time of 24 h, the initial mineralization rates (IMRs) ranged from 2.6 to 3.5 {micro}g{sm_bullet}L{sup {minus}1}{sm_bullet}min{sup {minus}1} for strain P106 and from 3.8 to 0.92 {micro}g{sm_bullet}L{sup {minus}1}{sm_bullet}min{sup {minus}1} for strain NY05. These IMRs were higher than those of soil-free controls and those predicted by a coupled desorption/biodegradation model, suggesting both strains of bacteria could access soil-sorbed biphenyl. For strain P106, biphenyl mineralization curves in slurries of four different soils were nearly coincident with those in soil-free systems containing the same total mass of biphenyl. This strain appeared to have immediate and complete access to the pool of sorbed biphenyl. The extent of bioavailability of soil-sorbed biphenyl decreased with increased aging. The decrease in availability was most pronounced within the first 80 days. The effect of soil organic matter content on bioavailability showed different trends for the two organisms.

  13. 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...

  14. 40 CFR 721.3480 - Halogenated biphenyl glycidyl ethers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Halogenated biphenyl glycidyl ethers... Substances § 721.3480 Halogenated biphenyl glycidyl ethers. (a) Chemical substance and significant new uses... ethers (PMNs P-90-1844, P-90-1845, and P-90-1846) are subject to reporting under this section for...

  15. 40 CFR 721.3480 - Halogenated biphenyl glycidyl ethers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Halogenated biphenyl glycidyl ethers... Substances § 721.3480 Halogenated biphenyl glycidyl ethers. (a) Chemical substance and significant new uses... ethers (PMNs P-90-1844, P-90-1845, and P-90-1846) are subject to reporting under this section for...

  16. 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

  17. 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

  18. Draft Genome Sequence of Cupriavidus pauculus Strain KF709, a Biphenyl-Utilizing Bacterium Isolated from Biphenyl-Contaminated Soil

    PubMed Central

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

    2015-01-01

    We report the draft genome sequence of Cupriavidus pauculus strain KF709, which comprises 6,826,799 bp with 6,272 coding sequences. The strain KF709 utilizes biphenyl and degrades low-chlorinated biphenyls; however, it possesses fewer coding sequences involved in the degradation of aromatic compounds than other strains belonging to the Betaproteobacteria. PMID:25814614

  19. Biodegradation of polyfluorinated biphenyl in bacteria.

    PubMed

    Hughes, David; Clark, Benjamin R; Murphy, Cormac D

    2011-07-01

    Fluorinated aromatic compounds are significant environmental pollutants, and microorganisms play important roles in their biodegradation. The effect of fluorine substitution on the transformation of fluorobiphenyl in two bacteria was investigated. Pseudomonas pseudoalcaligenes KF707 and Burkholderia xenovorans LB400 used 2,3,4,5,6-pentafluorobiphenyl and 4,4'-difluorobiphenyl as sole sources of carbon and energy. The catabolism of the fluorinated compounds was examined by gas chromatography-mass spectrometry and fluorine-19 nuclear magnetic resonance spectroscopy (19F NMR), and revealed that the bacteria employed the upper pathway of biphenyl catabolism to degrade these xenobiotics. The novel fluorometabolites 3-pentafluorophenyl-cyclohexa-3,5-diene-1,2-diol and 3-pentafluorophenyl-benzene-1,2-diol were detected in the supernatants of biphenyl-grown resting cells incubated with 2,3,4,5,6-pentafluorobiphenyl, most likely as a consequence of the actions of BphA and BphB. 4-Fluorobenzoate was detected in cultures incubated with 4,4'-difluorobiphenyl and 19F NMR analysis of the supernatant from P. pseudoalcaligenes KF707 revealed the presence of additional water-soluble fluorometabolites. PMID:20830605

  20. 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.

  1. 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.

  2. 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

  3. Mechanism of hydroxylation of biphenyl by Cunninghamella echinulata.

    PubMed Central

    Smith, R V; Davis, P J; Clark, A M; Prasatik, S K

    1981-01-01

    The hydroxylation of [U-2H]biphenyl and [2,2',3,3',5,5',6,6'-2H]biphenyl by Cunninghamella echinulata A.T.C.C. 9244 has been studied. G.l.c.-mass-spectrometry analyses indicate the lack of an isotope effect during the hydroxylation of the perdeuterated substrate. Both g.l.c.-mass spectrometry and 1H n.m.r. were used to definitively demonstrate the presence of a 1,2-hydride-shift during the microbiological hydroxylation of [2,2',3,3',5,5',6,6'-2H]biphenyl. PMID:7306077

  4. Testing for polychlorinated biphenyls in human milk

    SciTech Connect

    Wickizer, T.M.; Brilliant, L.B.

    1981-09-01

    Reports of polychlorinated biphenyl (PCB) contamination of human milk have raised questions about the possible risks of breast-feeding and whether nursing mothers ought to have their breast milk tested. Current data on contamination of human milk are needed so that pediatricians can make informed recommendations about breast milk testing and breast-feeding. With consideration of recent findings of PCB contamination of human milk in Michigan, recommendations concerning breast milk testing and breast-feeding are made. No major changes in current breast-feeding practices are advised. However, breast milk testing is recommended for certain nursing mothers who have had potentially high exposure to PCBs. Limiting the duration of breast-feeding may also be advisable for mothers with high PCB milk fat levels in order to reduce infant exposure to PCBs.

  5. Polychlorinated biphenyls: influence on birthweight and gestation

    SciTech Connect

    Taylor, P.R.; Lawrence, C.E.; Hwang, H.L.; Paulson, A.S.

    1984-10-01

    Fifty-one infants born to women employed at two capacitor manufacturing facilities with a history of high exposure to polychlorinated biphenyls (PCBs) had a mean birthweight of 153 grams less than that of 337 infants born to women who had worked in low-exposure areas (90 per cent confidence interval, -286 to -20 g); mean gestational age was 6.6 days shorter in the high-exposure infants (90 per cent CI, -10.3 to -2.9 days). After adjusting for gestational age, the difference in birthweight was markedly reduced, indicating that the observed reduction in birthweight was due mainly to shortening of gestational age in the high-exposure group.

  6. 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...

  7. 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.

  8. DECHLORINATIONS OF POLYCHLORINATED BIPHENYLS IN SEDIMENTS OF NEW BEDFORD HARBOR

    EPA Science Inventory

    The breakdown of polychlorinated biphenyl (PCB) congeners in situ in sediments heavily contaminated with PCBs by processes called reductive dechlorinations have been reported. hese studies characterized several distinct dechlorination patterns, caused by different strains of anae...

  9. Effective inhibition of hydroxyl radicals by hydroxylated biphenyl compounds.

    PubMed

    Taira, J; Ikemoto, T; Mimura, K; Hagi, A; Murakami, A; Makino, K

    1993-01-01

    In aqueous media, approximate rate constants for the reactions between hydroxyl radicals (.OH) and biphenyl compounds such as dehydrodieugenol, magnolol, honokiol, dehydrodidihydroeugenol, dehydrodivanillyl alcohol, and dehydrodicreosol were estimated by competition reactions for .OH between these biphenyls and 5,5-dimethyl-1-pyrroline-N-oxide (DMPO). By measuring the decrease in the height of the EPR signals of the .OH spin adduct, rate constants in the order of 10(9) to 10(10) M were measured. PMID:8282234

  10. NUCLEOTIDE SEQUENCING AND TRANSCRIPTIONAL MAPPING OF THE GENES ENCODING BIPHENYL DIOXYGENASE, A MULTICOMPONENT 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. ix open reading frames were identified, four of which are, homologous to the components of toluene dioxy...

  11. 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...

  12. ENANTIOMER SEPARATION OF POLYCHLORINATED BIPHENYL ATROPISOMERS AND POLYCHLORINATED BIPHENYL RETENTION BEHAVIOR ON MODIFIED CYCLODEXTRIN CAPILLARY GAS CHROMATOGRAPHY COLUMNS

    EPA Science Inventory

    Seven commercially-available chiral capillary gas chromatography columns containing modified cyclodextrins were evaluated for their ability to separate enantiomers of the 19 stable chiral polychlorinated biphenyl (PCB) atropisomers, and for their ability to separate these enantio...

  13. KINETICS OF THE REACTIONS OF NAPHTHALENE AND BIPHENYL WITH OH RADICALS AND WITH O3 AT 294 + OR - 1 K

    EPA Science Inventory

    Naphthalene and biphenyl are the simplest members of the polycyclic aromatic hydrocarbons and the polyphenyls, respectively. In addition, biphenyl is the parent compound of the chlorine and bromine substituted biphenyls. However, these bicyclic aromatics are of a sufficiently low...

  14. 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

  15. 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. PMID:25877901

  16. 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

  17. 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.

  18. 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. PMID:19957996

  19. Formation of polybrominated dibenzofurans from polybrominated biphenyls.

    PubMed

    Altarawneh, Mohammednoor; Dlugogorski, Bogdan Z

    2015-01-01

    Decades after phasing out their production and use, especially in the formulations of brominated flame retardants (BFRs), polybrominated biphenyls (PBBs) still pose serious environmental and health problems. The oxidation of PBB has been hypothesised as a pathway for the formation of the notorious polybrominated dibenzofurans (PBDFs) and their dispersion in the environment. However, the exact reaction corridor remains misunderstood, with the existing mechanisms predicting the reaction to proceed via a high energy process that involves the breakage of C-C linkage (∼118.0 kcal mol(-1)) and the subsequent formation of bromophenols molecules, where the latter are supposed to act as precursors for the formation of PBDFs (∼40.0-60.0 kcal mol(-1)). Herein, we show that PBBs produce PBDFs in a facile mechanism through a series of highly exothermic reactions (i.e., overall barriers reside 8.2-10.0 kcal mol(-1) below the entrance channel). Whilst the fate of the ROO-type intermediates in oxidation of all aromatics is to emit CO or CO2, PBDFs constitute the dominant products from the oxidation of PBBs. Initially formed R-OO adduct evolves in a very exoergic mechanism to yield PBDFs. In view of the facile oxidative transformation of PBBs into PBDFs, we conclude that, it is unsafe to dispose BFRs in oxidation processes, as this practice generates high yields of toxic PBDFs. PMID:25303667

  20. 75 FR 34076 - Polychlorinated Biphenyls (PCBs); Reassessment of Use Authorizations; Extension of Comment Period...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-16

    ... AGENCY 40 CFR Part 761 RIN 2070-AJ38 Polychlorinated Biphenyls (PCBs); Reassessment of Use Authorizations..., Hazardous substances, Labeling, Polychlorinated biphenyls (PCBs), Reporting and recordkeeping requirements..., 2010, concerning the reassessment of the use authorizations for PCBs. This document extends the...

  1. 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.

  2. 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

  3. 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.

  4. 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.

  5. 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...

  6. 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...

  7. 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. his organism also cooxidizes several chlorinated biphenyl congeners. iphenyl dioxygenase activity in cell extract required addition of NAD(P)H as an electron donor for the conversion of biphenyl ...

  8. 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

  9. Incidence of thyroid disease following exposure to polybrominated biphenyls and polychlorinated biphenyls, Michigan, 1974-2006.

    PubMed

    Yard, Ellen E; Terrell, Metrecia L; Hunt, Danielle Rentz; Cameron, Lorraine L; Small, Chanley M; McGeehin, Michael A; Marcus, Michele

    2011-08-01

    Thyroid hormones, which influence body metabolism and development, could be affected by persistent organic pollutants. We sought to examine the relationship between polybrominated biphenyls (PBBs) and polychlorinated biphenyls (PCBs) and thyroid disease. We employed incidence density sampling to perform a nested case control analysis of the Michigan Long-Term PBB Cohort. Cohort members (n=3333) were exposed to PBBs through contaminated cattle feed in 1973-1974 and to PCBs through daily life. Those with detectable serum PBB and PCB concentrations at enrollment were categorized into tertiles of PBB and PCB exposure. Case-patients were cohort members answering "Yes" to "Has a healthcare provider ever told you that you had a thyroid problem?" during follow-up interviews; control-patients were cohort members answering "No". We used odds ratios (OR) with 95% confidence intervals (CI) to compare odds of thyroid disease by PBB and PCB exposure and by various risk factors. Total cumulative thyroid disease incidence after 33 years was 13.9% among women and 2.6% among men. After adjusting for body mass index, we found no statistically significant differences in odds of any type of thyroid disease among women or men with elevated PBB or PCB exposure. Compared to control-patients, women with thyroid disease had increased odds of being overweight/obese (OR=2.82, 95% CI: 1.94-4.11) and developing infertility (OR=1.71, 95% CI: 1.08-2.69), diabetes (OR=1.61, 95% CI: 1.04-2.51), or arthritis (OR=1.71, 95% CI: 1.18-2.50) during follow-up. Additional research should explore potential associations between PBBs/PCBs and thyroid disease among children exposed in utero. PMID:21737118

  10. Thyrotoxic and dopaminergic effects of polychlorinated biphenyls

    SciTech Connect

    Ness, D.K.

    1994-01-01

    Perturbations in the developing nervous system have been associated with perinatal exposures to polychlorinated biphenyls (PCBs). To determine which PCBs accumulate in brain following perinatal exposure, Sprague-Dawley rats were exposed by gavage to Aroclor 1242 (4 or 16 mg/kg/day) during days 10-16 of gestation. At weaning (day 21), analysis of pup brain (frontal cortex, hippocampus, and caudate putamen) by gas chromatography revealed ten peaks representing 10-14 congeners in PCB-exposed animals. Brain PCB concentrations were greatest in high-dose pups for all congeners except for 2,4,4[prime]-trichlorobiphenyl (PCB 28) which had a higher concentration in the low-dose group. Congeners differed significantly in their degree of bioaccumulation, but no significant differences among brain regions were found. A lack of regionalization of PCB residues in the brain was also demonstrated by autoradiography in weanling rats treated iv with [[sup 14]C]-3,3[prime],4,4[prime]-tetrachlorobiphenyl or [[sup 14]C]-2,2[prime],4,4[prime]-tetrachlorobiphenyl. Time-mated Sprague-Dawley rats were exposed on days 10-16 of gestation to three environmentally-relevant PCBs: 2,4,4[prime]-trichlorobiphenyl (PCB 28), 8 or 32 mg/kg/day; 2,3[prime],4,4[prime],5-pentachlorobiphenyl (PCB 118), 4 or 16 mg/kg/day; or 2,2[prime],4,4[prime],5,5[prime]-hexachlorobiphenyl (PCB 153), 16 or 64 mg/kg/day. At weaning, serum total thyroxin, but not triiodothyronine, was markedly depressed in pups exposed perinatally to PCB 118 or 153; and thyroid glands from PCB 118-treated pups revealed histologic changes suggestive of sustained TSH stimulation. No significant PCB-induced changes were detected in the activity of the rate limiting enzyme in the synthesis of catecholamines, tyrosine hydroxylase, in the caudate putamen at weaning or in adulthood. Likewise no significant changes were detected in dopamine receptor (D1 and D2) concentrations in several regions in the mesocortical and nigrostriatal pathways.

  11. The transfer of polychlorinated biphenyls (PCBs) and polybrominated biphenyls (PBBs) across the human placenta and into maternal milk

    SciTech Connect

    Jacobson, J.L.; Fein, G.G.; Jacobson, S.W.; Schwartz, P.M.; Dowler, J.K.

    1984-04-01

    Cord serum and maternal milk levels of polychlorinated biphenyls (PCBs) and polybrominated biphenyls (PBBs) were examined in relation to maternal serum levels. Maternal serum levels were significantly higher than cord serum levels for both types of compounds. Placental passage was indicated by significant maternal to cord serum correlations for both PCBs (r . .42) and PBBs (r . .81). Correlations between maternal serum and milk levels were similar. Higher PBB correlations were probably due to greater reliability in the measurement of PBB levels in serum and milk.

  12. Transfer of polychlorinated biphenyls (PCBs) and polybrominated biphenyls (PBBs) across the human placenta and into maternal milk

    SciTech Connect

    Jacobson, J.L.; Fein, G.G.; Jacobson, S.W.; Schwartz, P.M.; Dowler, J.K.

    1984-04-01

    Cord serum and maternal milk levels of polychlorinated biphenyls (PCBs) and polybrominated biphenyls (PBBs) were examined in relation to maternal serum levels. Maternal serum levels were significantly higher than cord serum levels for both types of compounds. Placental passage was indicated by significant maternal to cord serum correlations for both PCBs (r = .42) and PBBs (r = .81). Correlations between maternal serum and milk levels were similar. Higher PBB correlations were probably due to greater reliability in the measurement of PBB levels in serum and milk.

  13. 77 FR 54863 - 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 proposed 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 to......

  14. DEVELOPMENTAL NEUROTOXICOLOGY OF POLYCHLORINATED BIPHENYLS AND RELATED COMPOUNDS

    EPA Science Inventory

    Polychlorinated biphenyls are stable, lipophilic industrial compounds that are present in residue levels in human tissue, wildlife and freshwater sediment. hey are toxic and are known to pass the placenta and intoxicate the fetus. wo large outbreaks of poisoning have occurred in ...

  15. FIBER OPTIC FLUOROIMMUNOSENSOR FOR THE DETECTION OF POLYCHLORINATED BIPHENYLS

    EPA Science Inventory

    There currently exists a critical and growing need for cost-effective, real-time, and in situ methods for detection of environmental pollutants such as polychlorinated biphenyls (PCBs). erein reported is a evanescent wave Fluoroimmunosensor for measurement of PCBS. 2,4-5-Trichlor...

  16. 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...

  17. 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...

  18. INTRAUTERINE EXPOSURE OF HUMANS TO PCBS (POLYCHLORINATED BIPHENYLS): NEWBORN EFFECTS

    EPA Science Inventory

    The effect of low-level chronic exposure to polychlorinated biphenyls (PCBs) from consumption of Lake Michigan fish was assessed in pregnant women and their newborn offspring. Low levels of PCBs remain in the human body for some time, and caused, in this sample, decreases in birt...

  19. POLYCHLORINATED BIPHENYLS IN PRECIPITATION IN THE LAKE MICHIGAN BASIN

    EPA Science Inventory

    Rainfall samples were collected in Chicago, Illinois, and on Beaver Island, Michigan, and analyzed for polychlorinated biphenyls (PCBs). The precipitation weighted mean concentration of 35 samples of rain was 111 mg/l. (111 parts per trillion). This would result in the deposition...

  20. HALF-LIFE OF POLYCHLORINATED BIPHENYLS IN OCCUPATIONALLY EXPOSED WORKERS

    EPA Science Inventory

    In 1977 and 1985, serum polychlorinated biphenyl (PCB) concentrations were determined for 58 workers in a Bloomington, Indiana, factory that used PCBs in capacitor manufacture until 1977. ess chlorinated PCBs were quantitated as Aroclor 1242, and more highly chlorinated PCBs were...

  1. 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...

  2. 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...

  3. 21 CFR 109.30 - Tolerances for polychlorinated biphenyls (PCB's).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 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...

  4. 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 FOOD-PACKAGING MATERIAL Tolerances...

  5. 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...

  6. 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...

  7. 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

  8. 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. PMID:26828632

  9. 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.

  10. Removal of polychlorinated biphenyls by desulfurization and emissions of polychlorinated biphenyls from sintering plants.

    PubMed

    Wang, Mengjing; Hou, Meifang; Zhao, Kai; Li, Haifeng; Han, Ying; Liao, Xiao; Chen, Xuebin; Liu, Wenbin

    2016-04-01

    The influence of desulfurization on polychlorinated biphenyls (PCBs) from sintering plants was investigated. The concentrations of dioxin-like (dl) PCBs, toxic equivalents (TEQs), indicator PCBs, and total tri- to deca-chlorinated PCB homolog groups (∑PCBs) in the flue gases at the desulfurization system inlets were 290-1906 pg m(-3) (2.4-18.8 pg World Health Organization (WHO) TEQ m(-3)), 420-2885 pg m(-3), and 6496-22,648 pg m(-3), respectively. Desulfurization reduced the values to 43.3-500 pg m(-3) (0.46-9.5 pg WHO-TEQ m(-3)), 183-587 pg m(-3), and 2383-11,639 pg m(-3), respectively. The removed PCBs were adsorbed by gypsum from the flue gas; the PCB concentration distributions at the inlets and outlets and in the gypsum samples were similar. The emission factors were 9.86 ng WHO-TEQ t(-1) for the flue gas and 8.37 ng WHO-TEQ t(-1) for gypsum. Desulfurization decreased the annual atmospheric PCB emissions from 48.6 to 30.7 g WHO-TEQ, and the estimated annual emissions in gypsum were 8.06 g WHO-TEQ. PCBs in the gypsum have not been effectively eliminated and will probably reenter the environment and in turn become a new source of PCB emission. The PCB concentrations in fly ashes from series-connected electrostatic precipitators clearly increased. PMID:26690582

  11. 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.

  12. 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

  13. 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.

  14. 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

    2016-01-01

    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 (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. PMID:26915282

  15. Synthesis, structural, spectroscopic and thermal characteristics of disubstituted biphenyl derivative: Biphenyl-4,4‧-diacetic acid

    NASA Astrophysics Data System (ADS)

    Sienkiewicz-Gromiuk, Justyna; Głuchowska, Halina; Tarasiuk, Bogdan; Mazur, Liliana; Rzączyńska, Zofia

    2014-07-01

    A novel 4,4‧-disubstituted biphenyl derivative featuring two acetic acid side arms symmetrically attached to a biphenyl system, that is biphenyl-4,4‧-diacetic acid (H2bpda), has been successfully synthesized by means of the three-stage organic strategy. The synthesis product was characterized by elemental analysis, various spectroscopic techniques including FT-IR, Raman, 1H and 13C NMR as well as thermogravimetric and TG-FT-IR coupled measurements. The phase purity of material was verified on the basis of the X-ray powder diffraction. The studied compound crystallizes in the monoclinic P21/c space group with half of the molecule in the asymmetric unit. Structural studies indicate intermolecular Osbnd H⋯O hydrogen bonding between the carboxylic groups of the adjacent molecules of H2bpda. The occurrence of intermolecularly associated carboxylic groups can also be clearly seen in the vibrational spectra of the acid. On thermal analysis both in air and nitrogen an anhydrous compound demonstrates considerable thermal stability.

  16. 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.

  17. 40 CFR 721.10417 - Biphenyl alkyl morpholino ketone (generic) (P-11-338).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (generic) (P-11-338). 721.10417 Section 721.10417 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... 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...

  18. 40 CFR 721.10417 - Biphenyl alkyl morpholino ketone (generic) (P-11-338).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (generic) (P-11-338). 721.10417 Section 721.10417 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... 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...

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

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (generic) (P-11-338). 721.10417 Section 721.10417 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... 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...

  20. 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.

  1. O-Methyltransferases involved in biphenyl and dibenzofuran biosynthesis.

    PubMed

    Khalil, Mohammed N A; Brandt, Wolfgang; Beuerle, Till; Reckwell, Dennis; Groeneveld, Josephine; Hänsch, Robert; Gaid, Mariam M; Liu, Benye; Beerhues, Ludger

    2015-07-01

    Biphenyls and dibenzofurans are the phytoalexins of the Malinae involving apple and pear. Biosynthesis of the defence compounds includes two O-methylation reactions. cDNAs encoding the O-methyltransferase (OMT) enzymes were isolated from rowan (Sorbus aucuparia) cell cultures after treatment with an elicitor preparation from the scab-causing fungus, Venturia inaequalis. The preferred substrate for SaOMT1 was 3,5-dihydroxybiphenyl, supplied by the first pathway-specific enzyme, biphenyl synthase (BIS). 3,5-Dihydroxybiphenyl underwent a single methylation reaction in the presence of S-adenosyl-l-methionine (SAM). The second enzyme, SaOMT2, exhibited its highest affinity for noraucuparin, however the turnover rate was greater with 5-hydroxyferulic acid. Both substrates were only methylated at the meta-positioned hydroxyl group. The substrate specificities of the OMTs and the regiospecificities of their reactions were rationalized by homology modeling and substrate docking. Interaction of the substrates with SAM also took place at a position other than the sulfur group. Expression of SaOMT1, SaOMT2 and SaBIS3 was transiently induced in rowan cell cultures by the addition of the fungal elicitor. While the immediate SaOMT1 products were not detectable in elicitor-treated cell cultures, noraucuparin and noreriobofuran accumulated transiently, followed by increasing levels of the SaOMT2 products aucuparin and eriobofuran. SaOMT1, SaOMT2 and SaBIS3 were N- and C-terminally fused with the super cyan fluorescent protein and a modified yellow fluorescent protein, respectively. All the fluorescent reporter fusions were localized to the cytoplasm of Nicotiana benthamiana leaf epidermis cells. A revised biosynthetic pathway of biphenyls and dibenzofurans in the Malinae is presented. PMID:26017378

  2. Mesomorphic and luminescent properties of disubstituted polyacetylenes bearing biphenyl pendants

    NASA Astrophysics Data System (ADS)

    Lam, Jacky W. Y.; Law, Chi Kong; Dong, Yuping; Wang, Jiannong; Ge, Weikun; Tang, Ben Zhong

    2003-01-01

    Liquid crystalline and light emitting properties of two new disubstituted polyacetylenes bearing biphenyl pendants (-{(R)CC[(CH 2) 4OCO-Biph-OC 7H 15]} n-, RCH 3 ( 1), C 6H 5 ( 2), Biph=4,4 '-biphenylyl) were investigated. Whereas 1 formed enantiotropic nematic phase, 2 was non-mesomorphic. Upon photoexcitation, the THF solutions of 1 and 2 emitted strong UV and blue light of 369 and 460 nm, respectively, whose quantum efficiencies were higher than that of poly(1-phenyl-1-octyne), a highly luminescent disubstituted polyacetylene.

  3. 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.

  4. 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.

  5. 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.

  6. OXIDATION OF POLYCHLORINATED BIPHENYLS BY PSEUDOMONAS SP. STRAIN LB400 AND PSEUDOMONAS PSEUDOAL-CALIGENES 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. hese results are attributed to differences in the...

  7. Induction of bphA, Encoding Biphenyl Dioxygenase, in Two Polychlorinated Biphenyl-Degrading Bacteria, Psychrotolerant Pseudomonas Strain Cam-1 and Mesophilic Burkholderia Strain LB400

    PubMed Central

    Master, Emma R.; Mohn, William W.

    2001-01-01

    We investigated induction of biphenyl dioxygenase in the psychrotolerant polychlorinated biphenyl (PCB) degrader Pseudomonas strain Cam-1 and in the mesophilic PCB degrader Burkholderia strain LB400. Using a counterselectable gene replacement vector, we inserted a lacZ-Gmr fusion cassette between chromosomal genes encoding the large subunit (bphA) and small subunit (bphE) of biphenyl dioxygenase in Cam-1 and LB400, generating Cam-10 and LB400-1, respectively. Potential inducers of bphA were added to cell suspensions of Cam-10 and LB400-1 incubated at 30°C, and then beta-galactosidase activity was measured. Biphenyl induced beta-galactosidase activity in Cam-10 to a level approximately six times greater than the basal level in cells incubated with pyruvate. In contrast, the beta-galactosidase activities in LB400-1 incubated with biphenyl and in LB400-1 incubated with pyruvate were indistinguishable. At a concentration of 1 mM, most of the 40 potential inducers tested were inhibitory to induction by biphenyl of beta-galactosidase activity in Cam-10. The exceptions were naphthalene, salicylate, 2-chlorobiphenyl, and 4-chlorobiphenyl, which induced beta-galactosidase activity in Cam-10, although at levels that were no more than 30% of the levels induced by biphenyl. After incubation for 24 h at 7°C, biphenyl induced beta-galactosidase activity in Cam-10 to a level approximately four times greater than the basal level in cells incubated with pyruvate. The constitutive level of beta-galactosidase activity in LB400-1 grown at 15°C was approximately five times less than the level in LB400-1 grown at 30°C. Thus, there are substantial differences in the effects of physical and chemical environmental conditions on genetic regulation of PCB degradation in different bacteria. PMID:11375179

  8. 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

  9. Pseudomonas putida KF715 bphABCD operon encoding biphenyl and polychlorinated biphenyl degradation: Cloning, analysis, and expression in soil bacteria

    SciTech Connect

    Hayase, Nobuki; Taira, Kazunari; Furukawa, Kensuke )

    1990-02-01

    The authors cloned the entire bphABCD genes encoding degradation of biphenyl and polychlorinated biphenyls to benzoate and chlorobenzoates from the chromosomal DNA of Pseudomonas putida KF715. The nucleotide sequence revealed two open reading frames corresponding to the bphC gene encoding 2,3-dihydroxybiphenyl dioxygenase and the bphD gene encoding 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid (ring-meta-cleavage compound) hydrolase.

  10. Degradation of polychlorinated biphenyls using mesoporous iron-based spinels.

    PubMed

    Huang, Linyan; Su, Guijin; Zhang, Aiqian; Shi, Yali; Xia, Chaobo; Lu, Huijie; Li, Liewu; Liu, Sha; Zheng, Minghui

    2013-10-15

    A series of mesoporous iron-based spinel materials were synthesized to degrade polychlorinated biphenyls (PCBs), with CB-209 being used as a model compound. The materials were characterized by X-ray powder diffraction (XRD), pore structure analysis, and X-ray photoelectron spectroscopy (XPS). A comparison of the dechlorination efficiencies (DEs) of the materials revealed that NiFe2O4 had the highest DE, followed by Fe3O4. Newly produced polychlorinated biphenyls, chlorinated benzenes, hydroxyl species and organic acids were detected by gas chromatography-mass spectrometry, high performance liquid chromatography-mass spectrometry and ion chromatograph. Identification of the intermediate products indicates that three degradation pathways, hydrodechlorination, the breakage of CC bridge bond and oxidative reaction, accompanied by one combination reaction, are competitively occurring over the iron-based spinels. The relative amounts of produced three NoCB isomers were illustrated by the CCl BDEs of CB-209 at meta-, para- and ortho-positions, and their energy gap between HOMO and LUMO. The consumption of the reactive oxygen species caused by the transformation of Fe3O4 into Fe2O3 in the Fe3O4 reaction system, and the existence of the highly reactive O2(-) species in the NiFe2O4 reaction system, could provide a reason why the oxidation reaction was more favored over NiFe2O4 than Fe3O4. PMID:23974532

  11. Polychlorinated biphenyl residues in sandstorm depositions in Beijing, China.

    PubMed

    Fu, Shan; Yang, Zhong-Zhi; Li, Ke; Xu, Xiao-Bai

    2008-10-01

    Sandstorms, which distribute many particles, are a special atmospheric occurrence and are frequent in northern China. We conducted this study to determine, for the first time, the concentration of polychlorinated biphenyls (PCBs) in sandstorm depositions. We collected 13 samples from urban areas of Beijing, and we measured a total of 144 PCB congeners. Thirteen samples all contained PCB residues. The total PCB concentration ranged from 1.6 to 15.6ngg(-1) (median, 4.8ngg(-1), dry weight), with trichlorinated biphenyls as the predominant homologue (>50.4%). Furthermore, we observed increasing PCB contamination from northwest to east Beijing. We later explored possible factors affecting contamination of the sandstorm depositions, which revealed a significant correlation between SigmaPCBs and the minimum particle size of the sandstorm deposition samples. Principal-component analysis revealed that the major source of PCBs in Beijing may be potentially associated with the number-one commercial PCB through the long-range transmission. In previous results, PCBs were not a severe component of contamination in sandstorm depositions of Beijing. However, this study suggested that sandstorm deposition may be a potential source of exposure to PCBs for the residents of Beijing, China. PMID:18674798

  12. 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.

  13. Conduction mechanisms in biphenyl dithiol single-molecule junctions

    NASA Astrophysics Data System (ADS)

    Bürkle, M.; Viljas, J. K.; Vonlanthen, D.; Mishchenko, A.; Schön, G.; Mayor, M.; Wandlowski, T.; Pauly, F.

    2012-02-01

    Based on density-functional theory calculations, we report a detailed study of the single-molecule charge-transport properties for a series of recently synthesized biphenyl-dithiol molecules [D. Vonlanthen , Angew. Chem., Int. Ed.1433-785110.1002/anie.200903946 48, 8886 (2009); A. Mishchenko , Nano Lett.NALEFD1530-698410.1021/nl903084b 10, 156 (2010)]. The torsion angle ϕ between the two phenyl rings, and hence the degree of π conjugation, is controlled by alkyl chains and methyl side groups. We consider three different coordination geometries, namely, top-top, bridge-bridge, and hollow-hollow, with the terminal sulfur atoms bound to one, two, and three gold surface atoms, respectively. Our calculations show that different coordination geometries give rise to conductances that vary by one order of magnitude for the same molecule. Irrespective of the coordination geometries, the charge transport calculations predict a cos2ϕ dependence of the conductance, which is confirmed by our experimental measurements. We demonstrate that the calculated transmission through biphenyl dithiols is typically dominated by a single transmission eigenchannel formed from π electrons. For perpendicular orientation of the rings a residual conductance arises from σ-π couplings. But only for a single molecule with a completely broken conjugation we find a nearly perfect degeneracy of the σ-π eigenchannels for the hollow-hollow-type contact in our theory.

  14. 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. PMID:24039134

  15. 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.

  16. 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

  17. Mechanistic insights on the hydrodesulfurization of biphenyl-2-thiol with nickel compounds.

    PubMed

    Torres-Nieto, Jorge; Brennessel, William W; Jones, William D; García, Juventino J

    2009-03-25

    The reactivity of the nickel(I) dimer [(dippe)Ni(mu-H)](2) (1) with biphenyl-2-thiol was explored with the aim of clarifying the key step of sulfur extrusion during the hydrodesulfurization process using dibenzothiophene (DBT). These reactions were monitored by variable temperature NMR experiments which allowed the complete characterization and isolation of [(dippe)(2)Ni(2)(mu-H)(mu-S-2-biphenyl)] (3). The latter compound evolves to the terminal nickel-hydride [(dippe)Ni (eta(1)-C-2-biphenyl)(H)] (4) and transient [(dippe)NiS] (5), to ultimately yield [(dippe)(2)Ni(2)(mu-S)] (2) and biphenyl as the resulting HDS products. The reactivity of 1 and biphenyl-2-thiol was examined using different ratios of reactants, which allowed preparation of [(dippe)Ni(eta(1)-S-biphenyl-2-thiolate)(2)] (6) when using an excess of this substrate. The reactivity of 6 with 1 was addressed, yielding compound 2 and an equivalent amount of biphenyl. PMID:19292493

  18. 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

  19. 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.

  20. Polychlorinated biphenyls: persistent pollutants with immunological, neurological, and endocrinological consequences.

    PubMed

    Crinnion, Walter J

    2011-03-01

    Polychlorinated biphenyls (PCBs) are considered "persistent organic pollutants;" fat-soluble compounds that bioaccumulate in individuals and bio-magnify in the food chain. PCBs were the first industrial compounds to experience a worldwide ban on production because of their potent toxicity. These compounds are still present in our food supply (fish, dairy, hamburger, and poultry being the most contaminated) and our bodies. Once in the body, they can cause long-term problems, especially for those exposed in utero. PCB bioaccumulation can lead to reduced infection fighting ability, increased rates of autoimmunity, cognitive and behavioral problems, and hypothyroidism. Some research also links PCBs to increased rates of type 2 diabetes. Testing is currently available for some of the most damaging PCBs. The testing compares individual levels to national reference values and can be interpreted to determine current exposure. Dietary measures can be enacted that will reduce PCB half-lives in humans by increasing excretion. PMID:21438643

  1. 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.

  2. Studies on the vapor behavior of selected polychlorinated biphenyls.

    PubMed

    Haque, R; Kohnert, R

    1976-01-01

    The vapor loss of several PCB isomers from stainless steel planchets surfaces has been studied. Experiments were carried out under two different conditions. In one case, the vapor loss was observed from 2 molecular layers of PCB, while in the other series, the loss from approximately 200 molecular layers was observed. In both cases the loss of PCB from the surface was substantial, although the controlling mechanism of vapor loss was different. In the first case, the transport was approximated by a simple first order rate law, whereas in the latter case, it was a diffusion controlled process. In general, the vapor loss decreased with increasing number of chlorine atoms present in the isomer. The 4,4(1)-dichlorobiphenyl showed a deviation as compared to others indicating that such factors as the electronic distribution, position of chlorine atom on the biphenyl ring and symmentry of the molecule are also important in discussing the vapor transport. PMID:824339

  3. Gas chromatographic separation of methoxylated polychlorinated biphenyl atropisomers

    PubMed Central

    Kania-Korwel, Izabela; Vyas, Sandhya M.; Song, Yang; Lehmler, Hans-Joachim

    2008-01-01

    Several polychlorinated biphenyls (PCBs) and their hydroxylated metabolites display axial chirality. Here we describe an enantioselective, gas chromatographic separation of methylated derivatives of hydroxylated (OH-)PCB atropisomers (MeO-PCB) using a chemically bonded β-cyclodextrin column (Chirasil-Dex). The atropisomers of several MeO-PCBs could be separated on this column with resolutions ranging from 0.42–0.87 under isothermal or temperature-programmed conditions. In addition, the enantiomeric fraction of OH-PCB 136 metabolites was determined in male and female rats treated with racemic PCB 136. The methylated derivatives of two OH-PCB 136 metabolites showed an enantiomeric enrichment in liver tissue, whereas PCB 136 itself was near racemic. PMID:18760792

  4. Polychlorinated biphenyls (PCBs) in transit system electrical equipment

    NASA Astrophysics Data System (ADS)

    1984-05-01

    The legislative history and current regulatory requirements concerning the continued use of PolyChlorinated Biphenyls PCBs in transit system electrical equipment are presented. The recent rule-making by the EPA is presented in summary form to aid the reader in following the chronology of requirements affecting the continued operation, servicing, marking, and disposal of transit system electrical equipment which contains PCB materials. Types of transit system electrical equipment regulated by the EPA are identified and future regulatory requirements concerning allowable PCB concentration levels of specific electrical equipment are outlined. Transit system procedures for the handling of electrical equipment containing PCBs are presented and recommendations to assist transit systems in eliminating PCBs from electrical equipment are provided.

  5. Dehalorespiration with Polychlorinated Biphenyls by an Anaerobic Ultramicrobacterium▿

    PubMed Central

    May, Harold D.; Miller, Greg S.; Kjellerup, Birthe V.; Sowers, Kevin R.

    2008-01-01

    Anaerobic microbial dechlorination is an important step in the detoxification and elimination of polychlorinated biphenyls (PCBs), but a microorganism capable of coupling its growth to PCB dechlorination has not been isolated. Here we describe the isolation from sediment of an ultramicrobacterium, strain DF-1, which is capable of dechlorinating PCBs containing double-flanked chlorines added as single congeners or as Aroclor 1260 in contaminated soil. The isolate requires Desulfovibrio spp. in coculture or cell extract for growth on hydrogen and PCB in mineral medium. This is the first microorganism in pure culture demonstrated to grow by dehalorespiration with PCBs and the first isolate shown to dechlorinate weathered commercial mixtures of PCBs in historically contaminated sediments. The ability of this isolate to grow on PCBs in contaminated sediments represents a significant breakthrough for the development of in situ treatment strategies for this class of persistent organic pollutants. PMID:18223104

  6. 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)

  7. 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. PMID:26088458

  8. 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). PMID:12117298

  9. 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.

  10. 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.

  11. [Analysis of polychlorinated biphenyls and organochlorine pesticides in pine needles].

    PubMed

    Kozul, Darija; Herceg Romanić, Snjezana

    2007-12-01

    This paper presents a review of methods for the analysis of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in pine needles. These compounds are lipophilic, they accumulate in the biotic and abiotic part of the environment in which they are persistent, and their use is forbidden or restricted due to harmful effects on human and animal health. Pine needles are convenient for monitoring the levels of organochlorine compounds in the air because they accumulate them in wax with which they are covered. However, the presence of many other compounds makes them complex for analysis. Analytical methods for determining organochlorine compounds in pine needles include sample collection, extraction of compounds with a suitable solvent, extract clean-up from unwanted compounds and qualitative and quantitative analysis. PCBs and OCPs are present in pine needles in traces, and every part of the analytical procedure has to be as efficient and selective as possible. PMID:18063531

  12. 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

  13. 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.

  14. GUIDELINES FOR THE DISPOSAL OF PCBS (POLYCHLORINATED BIPHENYLS) AND PCB ITEMS BY THERMAL DESTRUCTION

    EPA Science Inventory

    The report is a resource and guidelines document to aid EPA Regional Offices in interpreting and applying polychlorinated biphenyl (PCB) regulations to the thermal destruction of PCBs. As background material, the report describes fundamental processes of combustion, thermal destr...

  15. 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...

  16. TECHNICAL/ECONOMIC ASSESSMENT OF SELECTED PCB (POLYCHLORINATED BIPHENYL) DECONTAMINATION PROCESSES

    EPA Science Inventory

    Eleven emerging alternative treatments for polychlorinated biphenyl (PCB) contaminated sediments have been compared and ranked using technical performance, status of development, test and evaluation data needs, and cost as factors. In ranking the processes, weights were assigned ...

  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. 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...

  19. 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...

  20. PARTITIONING OF POLYCHLORINATED BIPHENYL CONGENERS IN SEAWATER OF NEW BEDFORD HARBOR, MASSACHUSETTS

    EPA Science Inventory

    The partitioning of polychlorinated biphenyls (PCBS) between particulate and dissolved phases of seawater was examined along a concentration gradient in New Bedford Harbor, MA. egression analysis was used to examine the relationship between the log of the partition coefficients (...

  1. Synthesis, characterization and fluorescence studies of novel bi-phenyl based acrylate and methacrylate

    NASA Astrophysics Data System (ADS)

    Baskar, R.; Subramanian, K.

    2011-09-01

    4-[(1 E)-3-(biphenyl-4-yl)buta-1,3-dien-1-yl]phenyl prop-2-enoate ( ACH) and 4-[(1 E)-3-(biphenyl-4-yl)buta-1,3-dien-1-yl]phenyl 2-methylprop-2-enoate ( MCH) was synthesized from biphenyl in three steps and their structures were confirmed by elemental analysis, IR, NMR ( 1H, 13C, DEPT135, 1H- 1H COSY, 1H- 13C HSQC and 1H- 13C HMBC) spectroscopic techniques. In this present study, various physicochemical characteristics we demonstrate solubility, color, absorbance and fluorescence property of novel biphenyl based acrylate and methacrylate measured in different solvents like benzene, dichloromethane, tetrahydrofuran, acetonitrile, dimethylsulfoxide and ethanol.

  2. 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

  3. 77 FR 74006 - Polychlorinated Biphenyls (PCBs); Recycling Plastics From Shredder Residue

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-12

    ... AGENCY Polychlorinated Biphenyls (PCBs); Recycling Plastics From Shredder Residue AGENCY: Environmental... plastic separated from shredder residue under the conditions described in the Voluntary Procedures for Recycling Plastics from Shredder Residue, relying principally on the regulatory provisions for excluded...

  4. 78 FR 20640 - Polychlorinated Biphenyls (PCBs); Recycling Plastics from Shredder Residue

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-05

    ... Residue (77 FR 74006). Additional background information on recycling activities that would be affected by... 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...

  5. MONITORING FOR POLYCHLORINATED BIPHENYL EMISSIONS FROM AN ELECTROLYTIC CAPACITOR DISPOSAL PROJECT

    EPA Science Inventory

    Three different air sampling methods were used simultaneously to monitor for PCB emissions arising from a pilot disposal project involving electrolytic capacitors. Analytical results indicated that the primary polychlorinated biphenyl material was Aroclor 1242, and that airborne ...

  6. METHODS FOR DETERMINING THE POLYCHLORINATED BIPHENYL EMISSIONS FROM INCINERATION AND CAPACITOR AND TRANSFORMER FILLING PLANTS

    EPA Science Inventory

    Described are methods to measure the polychlorinated biphenyl (PCB) emissions from the stacks of municipal waste, industrial waste, and sewage sludge incinerators and from capacitor and transformer filling plants. The PCB emissions from the incineration plants are collected by im...

  7. MEASUREMENT OF FUGITIVE ATMOSPHERIC EMISSIONS OF POLYCHLORINATED BIPHENYLS FROM HAZARDOUS WASTE LANDFILLS

    EPA Science Inventory

    Four landfills known to contain large quantities of polychlorinated biphenyls (PCBs) were monitored for atmospheric emissions: Three of these were uncontrolled and contained large numbers of electrical capacitors, many of which were scattered on the surface and leaking PCB askare...

  8. DETERMINATION OF POLYCHLORINATED BIPHENYLS USING MULTIPLE REGRESSION WITH OUTLIER DETECTION AND ELIMINATION

    EPA Science Inventory

    A method for the analysis of capillary column Polychlorinated biphenyl (PCB) data using regression analysis with outlier checking and elimination, COMSTAR, is presented and evaluated. his algorithm determines the best combination of the commercial PCB mixtures which best fits the...

  9. 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 ...

  10. POLYCHLORINATED BIPHENYL AND POLYCHLORINATED DIBENZOFURAN BIOMARKERS OF RISK ASSESSMENT IN ADOLESCENT CHILDREN AND THEIR MOTHERS

    EPA Science Inventory

    This is two cohort comparison study of endocrine and cytochrome P450 family 1 biomarkers for risk assessment of polychlorinalted biphenyls (PCBs)/polychlorinated dibenzofurans (PCDFs) induced developmental toxicities in the human. The subjects will be sexually mature adoles...

  11. Enhanced mineralization of polychlorinated biphenyls in soil inoculated with chlorobenzoate-degrading bacteria.

    PubMed Central

    Hickey, W J; Searles, D B; Focht, D D

    1993-01-01

    An Altamont soil containing no measurable population of chlorobenzoate utilizers was examined for the potential to enhance polychlorinated biphenyl (PCB) mineralization by inoculation with chlorobenzoate utilizers, a biphenyl utilizer, combinations of the two physiological types, and chlorobiphenyl-mineralizing transconjugants. Biphenyl was added to all soils, and biodegradation of 14C-Aroclor 1242 was assessed by disappearance of that substance and by production of 14CO2. Mineralization of PCBs was consistently greatest (up to 25.5%) in soils inoculated with chlorobenzoate degraders alone. Mineralization was significantly lower in soils receiving all other treatments: PCB cometabolizer (10.7%); chlorobiphenyl mineralizers (8.7 and 14.9%); and mixed inocula of PCB cometabolizers and chlorobenzoate utilizers (11.4 and 18.0%). However, all inoculated soils had higher mineralization than did the uninoculated control (3.1%). PCB disappearance followed trends similar to that observed with the mineralization data, with the greatest degradation occurring in soils inoculated with the chlorobenzoate-degrading strains Pseudomonas aeruginosa JB2 and Pseudomonas putida P111 alone. While the mechanism by which the introduction of chlorobenzoate degraders alone enhanced biodegradation of PCBs could not be elucidated, the possibility that chlorobenzoate inoculants acquired the ability to metabolize biphenyl and possibly PCBs was explored. When strain JB2, which does not utilize biphenyl, was inoculated into soil containing biphenyl and Aroclor 1242, the frequency of isolates able to utilize biphenyl and 2,5-dichlorobenzoate increased progressively with time from 3.3 to 44.4% between 15 and 48 days, respectively. Since this soil contained no measurable level of chlorobenzoate utilizers yet did contain a population of biphenyl utilizers, the possibility of genetic transfer between the latter group and strain JB2 cannot be excluded. PMID:8476293

  12. Synthesis and biological evaluation of biphenyl amides that modulate the US28 receptor.

    PubMed

    Kralj, Ana; Kurt, Elif; Tschammer, Nuska; Heinrich, Markus R

    2014-01-01

    To prepare and biologically evaluate 38 new potential US28 allosteric modulators, we employed a straightforward synthetic route involving radical arylation. The study was based on a former lead structure but with the dihydroisoquinolinone moiety replaced by substituted biphenyls. The investigation of structure-activity relationships among the new biphenyl-derived ligands led to a preliminary pharmacophore model and the discovery of four promising candidates with full inverse agonist properties. PMID:24265151

  13. Regional analysis of potential polychlorinated biphenyl degrading bacterial strains from China.

    PubMed

    Shuai, Jianjun; Yu, Xurun; Zhang, Jing; Xiong, Ai-Sheng; Xiong, Fei

    2016-01-01

    Polychlorinated biphenyls (PCBs), the chlorinated derivatives of biphenyl, are one of the most prevalent, highly toxic and persistent groups of contaminants in the environment. The objective of this study was to investigate the biodegradation of PCBs in northeastern (Heilongjiang Province), northern (Shanxi Province) and eastern China (Shanghai municipality). From these areas, nine soil samples were screened for PCB-degrading bacteria using a functional complementarity method. The genomic 16S rDNA locus was amplified and the products were sequenced to identify the bacterial genera. Seven Pseudomonas strains were selected to compare the capacity of bacteria from different regions to degrade biphenyl by HPLC. Compared to the biphenyl content in controls of 100%, the biphenyl content went down to 3.7% for strain P9-324, 36.3% for P2-11, and 20.0% for the other five strains. These results indicate that a longer processing time led to more degradation of biphenyl. PCB-degrading bacterial strains are distributed differently in different regions of China. PMID:27140507

  14. Ab initio study of biphenyl chemisorption on Si(001): Configurational stability

    NASA Astrophysics Data System (ADS)

    Mamatkulov, M.; Stauffer, L.; Minot, C.; Sonnet, Ph.

    2006-01-01

    We present an ab initio energetical and structural study of the configurational stability of the biphenyl molecule adsorbed on the Si(001) surface. A number of models in biphenyl tight-bridge, butterfly, twisted, and tilted configurations are considered. For an undissociated biphenyl adsorption, the tight-bridge configuration is found to be the most stable one, slightly favored over the butterfly configuration. The effect on the stability of various parameters is investigated. The position with respect to the surface of the first phenyl ring atom (C1) on which the second ring is bound plays a determinant role. The tilted dimer under the second ring mainly acts in the biphenyl butterfly and tilted configurations, and a second ring location above a silicon down-atom favors stability. The effect of the second ring height above the surface is also discussed. Our results allow us to classify these different contributions by decreasing importance. By the hypothesis of a dissociative biphenyl adsorption, the calculated adsorption energies are clearly lower than in the corresponding undissociated model and the dissociated butterfly configuration is largely favored. Comparing our results to the experimental data, we propose some interpretations relative to the weakly and strongly chemisorbed biphenyl molecule observed in the scanning tunneling microscopy experiments.

  15. 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.

  16. 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

  17. 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

  18. [Microbial anaerobic dechlorination of polychlorinated biphenyls in paddy soil slurry].

    PubMed

    Yang, Kai; Yao, Xiao-yan; Chen, Chen; Shen, Chao-feng; Qin, Zhi-hui; Huang, Rong-lang

    2015-10-01

    We studied the dechlorination process of Aroclor1260, a high-chlorinated polychlorinated biphenyls (PCBs) mixture in an anaerobic paddy soil slurry, and further analyzed the related microbial community structures. The Aroclor1260 was reduced up to 55.5% in the natural paddy soil slurry in 128 days, and the reduction percentage dropped to 46.9% after incoculating the paddy soil slurry with a PCBs-dechlorination enrichment culture. The dechlorination mainly occurred in congeners of pentachlorobiphenyl, hexachlorobiphenyl, and specially, the heptachlorobiphenyl, with pentachlorobiphenyl accumulated as dechlorination intermediate. Hydrogen gas produced from fermentation of organic matters was maintained at a lower partial pressure due to its consumption during the dechlorination process, so that the methanogens was suppressed as well. The microbial community structure was significantly different between natural and inoculated paddy soils. Introducing the PCBs-dechlorination enrichment culture changed the local microbial community by the competition between the exogenetic dchlorinators and the indigenous bacteria, overall decreasing the dechlorination activity. PMID:26995917

  19. Volatilization of extensively dechlorinated polychlorinated biphenyls from historically contaminated sediments

    SciTech Connect

    Bushart, S.P.; Bush, B.; Barnard, E.L.; Bott, A. |

    1998-10-01

    A study was conducted as a preliminary characterization of the ability of polychlorinated biphenyl (PCB)-contaminated sediments to volatilize PCBs into the air upon drying under conditions meant to be environmentally relevant. Sediments collected from the St. Lawrence River contained high levels of PCBs. The PCB contamination consisted of high levels of mainly ortho-substituted mono- and dichlorobiphenyls, suggesting that the original contamination had been transformed by microbial reductive dechlorination. These sediments lost 0.07 to 1.7% of their total PCB content to the air during a 24-h drying cycle. Sediments with varying amounts of overlying water lost significantly less PCB to the air within the first few cycles than native sediments with no overlying water. Losses due to PCB volatilization were well correlated to sediment PCB concentration and water loss but not to drying temperatures (4--43 C) within 24-h drying cycles. The PCB congeners representing >90% of those volatilized within the first 24 h of drying were those produced in the sediment samples as a result of microbial reductive dechlorination of the original PCB contamination. The presence of these congeners in volatilized air samples was positively confirmed by gas chromatography-mass spectrometry with Fourier transform infrared detection (FTIR). These results strongly suggest that significant amounts of mono-, di-, and trichlorobiphenyls may be volatilized from PCB-contaminated sediments at ambient environmental conditions and that this PCB volatilization may be enhanced by microbial reductive dechlorination.

  20. 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. PMID:20183511

  1. 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

  2. Prenatal Exposure to Polychlorinated Biphenyls: A Neuropsychologic Analysis

    PubMed Central

    Boucher, Olivier; Muckle, Gina; Bastien, Célyne H.

    2009-01-01

    Objectives A large body of literature documents the effects of prenatal exposure to polychlorinated biphenyls (PCBs) on cognitive development of children. Despite this fact, no integrative synthesis has been published yet to identify the cognitive functions that are particularly affected. Our aim is to review this literature in an attempt to identify the cognitive profile associated with prenatal PCB exposure. Data sources Studies were identified by searching the PubMed database for articles published before June 2008. We reviewed data from nine prospective longitudinal birth cohorts for different aspects of cognition. Data extraction Associations between indicators of prenatal PCB exposure and performance on cognitive tasks reported in the selected studies are summarized and classified as general cognitive abilities, verbal or visual–spatial skills, memory, attention, and executive functions. Data synthesis The most consistent effects observed across studies are impaired executive functioning related to increased prenatal PCB exposure. Negative effects on processing speed, verbal abilities, and visual recognition memory are also reported by most studies. Converging results from different cohort studies in which exposure arises from different sources make it unlikely that co-exposure with another associated contaminant is responsible for the observed effects. Conclusion Prenatal PCB exposure appears to be related to a relatively specific cognitive profile of impairments. Failure to assess functions that are specifically impaired may explain the absence of effects found in some studies. Our findings have implications in the selection of cognitive assessment methods in future studies. PMID:19165381

  3. 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.

  4. 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

  5. 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).

  6. Polychlorinated biphenyls emission from a medical waste incinerator in China.

    PubMed

    Chen, Tong; Li, Xiaodong; Yan, Jianhua; Jin, Yuqi

    2009-12-30

    Detailed polychlorinated biphenyls (PCBs) congener patterns were determined in the flue gas from a medical waste incinerator (MWI) using high-resolution gas chromatograph coupled to high-resolution mass spectrometer (HRGC/HRMS). The total PCBs concentration of all homologues (mono- to deca-chlorinated homologues) in the flue gas ranged from 138.01 to 855.35 ng/Nm(3) and the WHO-TEQ value varied from 0.046 to 0.549 ng/Nm(3) under the different operating conditions. PCB-77 concentration was the highest among dioxin-like PCBs and PCB-126 contributed mostly to the WHO-TEQ. The ratios of dioxin-like PCBs in the total PCB concentrations in the flue gas varied between 11.7% and 26.0% (the average value is 18.7%). Three inhibitors, sulfur, urea, and ammonium sulfate were tested to investigate the capacity for preventing PCBs formation. The decomposition efficiency for total PCBs and PCBs TEQ ranged from 38% to 84% and 69% to 92% respectively. It was shown that urea mixed with ammonium sulfate and more activated carbon was proved to be the most effective inhibitor for PCBs formation. The removal efficiencies (REs) of the total PCBs concentration and PCBs TEQ by the bag filter under two conditions were 69% and 85%, and 86% and 94% respectively. PMID:19744782

  7. 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. PMID:11345453

  8. 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.

  9. Polychlorinated Biphenyls in Residential Dust: Sources of Variability

    PubMed Central

    Whitehead, Todd P.; Brown, F. Reber; Metayer, Catherine; Park, June-Soo; Does, Monique; Dhaliwal, Joginder; Petreas, Myrto X.; Buffler, Patricia A.; Rappaport, Stephen M.

    2014-01-01

    We characterized the variability in concentrations of polychlorinated biphenyls (PCBs) measured in residential dust. Vacuum cleaner samples were collected from 289 homes in the California Childhood Leukemia Study during two sampling rounds from 2001 to 2010 and 15 PCBs were measured by high resolution gas chromatography–mass spectrometry. Median concentrations of the most abundant PCBs (i.e., PCBs 28, 52, 101, 105, 118, 138, 153, and 180) ranged from 1.0–5.8 ng per g of dust in the first sampling round and from 0.8–3.4 ng/g in the second sampling round. For each of these eight PCBs, we used a random-effects model to apportion total variation into regional variability (6–11%), intra-regional between-home variability (27–56%), within-home variability over time (18–52%), and within-sample variability (9–16%). In mixed-effects models, differences in PCB concentrations between homes were explained by home age, with older homes having higher PCB levels. Differences in PCB concentrations within homes were explained by decreasing time trends. Estimated half-lives ranged from 5–18 years, indicating that PCBs are removed very slowly from the indoor environment. Our findings suggest that it may be feasible to use residential dust for retrospective assessment of PCB exposures in studies of children’s health. PMID:24313682

  10. Temporal trends of polychlorinated biphenyls in precipitation in Beijing, China

    NASA Astrophysics Data System (ADS)

    Yang, Guosheng; Ma, Lingling; Xu, Diandou; Liu, Liyan; Jia, Hongliang; Chen, Yang; Zhang, Yongbao; Chai, Zhifang

    2012-09-01

    Temporal trend of polychlorinated biphenyls (PCBs) was determined in precipitation and monthly depositional fluxes were calculated in Beijing for the first time from February 2009 to March 2011. Total PCBs concentrations ranged from 7.00 to 993 ng L-1 in dissolved phase and from 1.00 to 133 ng L-1 in particulate phase, with a two orders of magnitude variation. Concentrations of PCBs were dominated by dissolved phase, which accounted for 82.5% of the total PCBs in precipitation, implying PCBs enrichment in rainwater due to efficient scavenging of highly contaminated gas phase and nonfilterable submicron particles which easily adsorbed organic contaminants in urban atmosphere. Highest concentrations of PCBs were measured in snow, which were about two times higher than those in rainwater, demonstrating more efficient scavenging of PCBs by snow. The sum of bi-, tri- and tetrachlorinated congeners accounted for 70.5% of total PCBs in precipitation, suggesting that PCBs mainly come from the historical usage of domestic PCB product, e.g., trichlorobiphenyl. PCBs concentrations in both dissolved and particulate phases showed slow rate of decline, with a half-life of 16.9 years in precipitation, suggesting that the atmospheric concentrations of PCBs were decreasing slowly in Beijing. The wet deposition flux of ∑PCBs ranged from 0.240 to 6.55 μg m-2 month-1 (mean: 1.41 μg m-2 month-1), indicating a relatively high level of PCBs contamination in Beijing atmosphere.

  11. 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. PMID:26805927

  12. PCB (polychlorinated biphenyls) concentrations in Wilson Reservoir catfish, 1985

    SciTech Connect

    Dycus, D.L.; Lowery, D.R.

    1986-09-01

    TVA conducted a study during autumn 1984 to determine concentrations of a variety of contaminants in biota from Wilson and upper Pickwick Reservoirs. Several contaminants were detected, with polychlorinated biphenyls (PCB) levels in catfish from Wilson Reservoir of greatest interest. PCB concentrations in twenty-two of 45 catfish from Wilson equaled or exceeded the Food and Drug Administration (FDA) tolerance of 2.0 ..mu..g/g and the average of all 45 was 2.6 ..mu..g/g. Contamination was widespread and did not show any geographical relationship to an embayment on Wilson Reservoir (Fleet Hollow) known to have PCBs in the sediments. As a result of these findings, the Northwest Alabama Regional Health Department issued an official notice to retail markets in June 1985 to discontinue selling catfish from Wilson Reservoir. TVA initiated studies to determine if there were other areas on Wilson with PCB contaminated sediments or PCB discharges, and an annual catfish collection was started in autumn 1985 to determine the year-to-year trend in PCB levels. As a follow-up to earlier studies, analyses of catfish collected during autumn 1985 indicated substantial reductions in PCB concentrations. Only 4 of 36 catfish had PCB concentrations which equaled or exceeded 2.0 ..mu..g/g and the overall average was 1.0 ..mu..g/g. Statistical analyses indicated PCB concentrations decreased with increased distance from Fleet Hollow. Further monitoring is recommended for 2 more years.

  13. 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.

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

    PubMed

    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

    2013-09-17

    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 five PCB congeners (105, 138, 153, 170, and 180) in carpet dust collected between 1998 and 2000 from 1187 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 PCB 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 [odds ratio (OR) range 1.01-1.04 for each percentage increase] or population density (OR 1.08 for every 1000/mi(2)) in each site. The number of industrial facilities within 2 km of a home was associated with PCB concentrations; however, facility type and direction of the association varied by site. Our findings suggest that outdoor sources of PCBs may be significant determinants of indoor concentrations. PMID:23952055

  15. 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

  16. 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.

  17. 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.

  18. Polychlorinated biphenyl release from resuspended Hudson River sediment.

    PubMed

    Schneider, Abby R; Porter, Elka T; Baker, Joel E

    2007-02-15

    Three shear turbulence resuspension mesocosms (STORM tanks) were used to examine the release of polychlorinated biphenyls (PCBs) from resuspended Hudson River sediment. Twenty-two percent of the resuspended PCBs desorbed after 2 h, and 35% +/- 8% of PCBs were in the dissolved phase after apparent steady state was reached in 2 days. After the first resuspension event, the solids were allowed to settle and the quiescent time was varied to determine whether the labile pool of PCBs is recharged during sediment consolidation. The steady-state log Koc values for the third subsequent resuspension were higher than for the first event due to lower dissolved PCB concentrations; the particulate PCB concentrations were constant between events. With 1 day of consolidation between resuspension events, the dissolved concentration of all congeners decreased an average of 8% +/- 5% between subsequent resuspension events. With 4 days between events, only the dissolved pentachlorinated PCBs decreased significantly (p = 0.002), suggesting that the easily desorbable PCBs recharge when there is sufficient time between resuspension events. PMID:17593705

  19. Amine-enhanced photodegradation of polychlorinated biphenyls. Final report

    SciTech Connect

    Meuser, J.M.; Weimer, W.C.

    1982-07-01

    Uncontrolled releases of polychlorinated biphenyls (PCBs) from transformers and capacitors pose a significant environmental problem to the electric utility industry. This report describes a series of experiments whose objective was to demonstrate the practicality of using natural solar radiation in conjunction with the application of an amine for in situ degradation of PCBs in contaminated soil. The soil tested was clay from beneath a capacitor rack at a pacific northwest utility substation. While no degradation of the PCBs in soil was found after two weeks of sunlight exposure, further solution experiments indicate that degradation of PCBs does occur in the presence of an amine and simulated solar radiation. In hexane solutions containing 1 ppM Aroclor 1268 with 10 and 100 ppM ethylenediamine, 37% and 53% reductions in PCB concentration, respectively, were found after 70 h of solar simulator irradiation. These results suggest that the clay matrix or other soil components may have interfered with the photodegradation process. Investigations into the reaction mechanism, reaction products, optimum treatment parameters and appropriate matrices appear to be warranted. Successful development of this in situ technique could lead to major savings in mitigation efforts for contaminated soils and surfaces.

  20. 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.

  1. 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.

  2. The internal barriers of rotation for the 209 polychlorinated biphenyls.

    PubMed

    Andersson, P L; Haglund, P; Tysklind, M

    1997-01-01

    The internal barrier of rotation (Erot) was calculated for all 209 polychlorinated biphenyls (PCBs) by using a semi-empirical method, viz. the Austin Model 1 (AMI) Hamiltonian. The difference in total energy between a forced planar state and an optimised twisted structure was defined as Erot. The Erot values were in the range of 8.33 to 483 kJ/mol, and were significantly influenced by the number of chlorine atoms in ortho position. An additional structural characteristic of the PCBs influencing Erot of ortho substituted congeners was substitution by chlorine atoms in vicinal meta positions, which is assumed to prevent outward bending of ortho substituents. This so-called buttressing effect contributed with 4 to 31 kJ/mol per added chlorine atom. In conclusion, the internal barrier of rotation, calculated for all 209 PCBs, provides an important structure dependent physico-chemical parameter for multivariate modelling of future quantitative structure-activity and structure-property relationships (QSARs/QSPRs). PMID:19005788

  3. 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. PMID:26798844

  4. Aqueous solubility of polychlorinated biphenyls related to molecular structure

    SciTech Connect

    Opperhulzen, A.; Gobas, F.A.P.C.; Van der Steen, J.M.D.; Hutzinger, O.

    1988-06-01

    Aqueous solubilities of polychlorinated biphenyls show a linear relationship between logarithms of aqueous activity coefficients and total surface areas (TSA) or total molecular volumes (TMV). The aqueous activity coefficients were calculated from experimental solubility data and values taken from the literature. The correlations improved substantially if a differential heat capacity between supercooled liquid and solid chemical (..delta..C/sub p/) equal to the entropy of fusion (..delta..S/sub f/), instead of ..delta..C/sub p/ = O, was assumed. In addition, it was found that dissolution of 2,2',4,4'-tetra- and 2,2',4,4'5,5'-hexachlorobiphenyl was accompanied by positive enthalpy and entropy changes, the entropy being dominant at room temperature. For the former compound, it was shown that the entropy of fusion is approximately to J K/sup -1/ mol/sup -1/, which is in agreement with the Walden rule. For 2,2',4,4',5,5'-hexachlorobiphenyl, it was shown that a Hildebrand plot provides a constant slope. This supported the assumption that differential heat capacity (..delta..C/sub p/) equals the entropy of fusion.

  5. 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

  6. 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. PMID:24997912

  7. 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. PMID:26398098

  8. Sorption of polychlorinated biphenyls by north sea sediments

    NASA Astrophysics Data System (ADS)

    Booij, Kees; van der Meer, Jaap; Kwast, Diana; de Boer, Joost L.

    1997-05-01

    The sediment-water partition coefficients ( Kd) of 32 polychlorinated biphenyls (PCBs) and penta- and hexachloro benzene were determined for 37 spiked sediment samples from the southern North Sea, the German Bight and the Norwegian Channel. Organic-carbon contents for these sediments were in the range 0.02-2.4%. Log( Kd) values were in the range 1.4 to 5.3. The largest difference between the organic-carbon normalised partition coefficients ( Koc) for individual components amounted to a factor of 10. Koc values for coarse sediments were generally lower than values for fine sediments. The solids concentration effect was evaluated using the Non-Settling Particles model, the Solute Complexation model, the Implicit Adsorbate model, and the Particle Interaction model. The latter three models could be rejected on the basis of the experimental evidence. The validity of ordinary least-squares regression for estimating slope and intercept of log( Koc)-log( KKow) relations is discussed. Differences in sediment characteristics cause changes in the intercept of log( Koc)-log( Kow) relations, but not in the slope. KKoc values of PCB isomers are inversely related to the number of chlorine atoms in the ortho position relative to the inter-ring bond. The validity of the data for estimating field values of sorption coefficients is discussed.

  9. Functional MRI approach to developmental methylmercury and polychlorinated biphenyl neurotoxicity.

    PubMed

    White, Roberta F; Palumbo, Carole L; Yurgelun-Todd, Deborah A; Heaton, Kristin J; Weihe, Pal; Debes, Frodi; Grandjean, Philippe

    2011-12-01

    Prenatal and early childhood exposure to methylmercury (MeHg) or polychlorinated biphenyls (PCBs) are associated with deficits in cognitive, sensory, motor and other functions measured by neurobehavioral tests. The main objective of this pilot study was to determine whether functional magnetic resonance imaging (fMRI) is effective for visualization of brain function alterations related to neurobehavior in subjects with high prenatal exposure to the two neurotoxicants, MeHg and PCBs. Twelve adolescents (all boys) from a Faroese birth cohort assembled in 1986-1987 were recruited based on their prenatal exposures to MeHg and PCB. All underwent fMRI scanning during behavioral tasks at age 15 years. Subjects with high mixed exposure to MeHg and PCBs were compared to those with low mixed exposure on fMRI photic stimulation and a motor task. Boys with low mixed exposures showed patterns of fMRI activation during visual and motor tasks that are typical of normal control subjects. However, those with high exposures showed activation in more areas of the brain and different and wider patterns of activation than the low mixed exposure group. The brain activation patterns observed in association with increased exposures to MeHg and PCBs are meaningful in regard to the known neurotoxicity of these substances. This methodology therefore has potential utility in visualizing structural neural system determinants of exposure-induced neurobehavioral dysfunction. PMID:21545807

  10. Environmental contamination of ready meals by polychlorinated biphenyls (PCBs).

    PubMed

    Adenugba, Adeola A; McMartin, Dena W; Beck, Angus

    2012-01-01

    The level of polychlorinated biphenyls (PCBs) contamination in ready meals was investigated to determine exposure compared to other foodstuffs. Chilled ready meals from nine categories (ambient, Chinese, Indian, Traditional UK, Italian, American Tex-Mex, Vegetarian and Organic), and three samples within each category were Soxhlet extracted in triplicate with hexane for 24 h, followed by a clean-up on deactivated silica gel. The cleaned extracts were concentrated to 1 ml under N(2) gas and analyzed on gas chromatography mass spectrometry (GC-MS) for 7 target PCBs (congeners 28, 52, 101, 118, 153, 138, and 180). Individual congener concentrations ranged from non-detectable to 0.40 ng g(-1) (wet weight). The cumulative concentration of all congeners (ΣPCBs) ranged between 0.20 and 1.00 ng g(-1) (wet weight). These values translate into exposure levels of less than 1 μg kg(-1)day(-1) for reference men and women of 70 and 57 kg, respectively. This preliminary study demonstrates that ready meals, like many other foods, are contaminated by PCBs and may represent an important route of human exposure given contemporary changes in consumer food choice. Even though low levels of contamination were observed, long-term exposure for population groups consuming a high volume of ready meals may have cause for concern regarding chronic health risks. PMID:22934994

  11. Functional MRI approach to developmental methylmercury and polychlorinated biphenyl neurotoxicity

    PubMed Central

    White, Roberta F.; Palumbo, Carole L.; Yurgelun-Todd, Deborah A.; Heaton, Kristin J.; Weihe, Pal; Debes, Frodi; Grandjean, Philippe

    2015-01-01

    Prenatal and early childhood exposure to methylmercury (MeHg) or polychlorinated biphenyls (PCBs) are associated with deficits in cognitive, sensory, motor and other functions measured by neurobehavioral tests. The main objective of this pilot study was to determine whether functional magnetic resonance imaging (fMRI) is effective for visualization of brain function alterations related to neurobehavior in subjects with high prenatal exposure to the two neurotoxicants, MeHg and PCBs. Twelve adolescents (all boys) from a Faroese birth cohort assembled in 1986–1987 were recruited based on their prenatal exposures to MeHg and PCB. All underwent fMRI scanning during behavioral tasks at age 15 years. Subjects with high mixed exposure to MeHg and PCBs were compared to those with low mixed exposure on fMRI photic stimulation and a motor task. Boys with low mixed exposures showed patterns of fMRI activation during visual and motor tasks that are typical of normal control subjects. However, those with high exposures showed activation in more areas of the brain and different and wider patterns of activation than the low mixed exposure group. The brain activation patterns observed in association with increased exposures to MeHg and PCBs are meaningful in regard to the known neurotoxicity of these substances. This methodology therefore has potential utility in visualizing structural neural system determinants of exposure-induced neurobehavioral dysfunction. PMID:21545807

  12. Binding of polychlorinated biphenyls to the aryl hydrocarbon receptor.

    PubMed Central

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

    1993-01-01

    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 lipophilicities, 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 other polyhalogenated and mixed polyhalogenated 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 hazardous aromatic xenobiotics. Images p422-a Figure 2. PMID:8119253

  13. Classification of the biphenyl- and polychlorinated biphenyl-degrading strain LB400T and relatives as Burkholderia xenovorans sp. nov.

    PubMed

    Goris, Johan; De Vos, Paul; Caballero-Mellado, Jesús; Park, Joonhong; Falsen, Enevold; Quensen, John F; Tiedje, James M; Vandamme, Peter

    2004-09-01

    Strain LB400T is the best-studied polychlorinated biphenyl (PCB) degrader. This organism has previously been allocated in the genus Burkholderia, since its 16S rRNA gene sequence shows 98.6 % sequence similarity to the type strains of Burkholderia graminis and Burkholderia terricola. A polyphasic study was undertaken to clarify the actual taxonomic position of this biotechnologically important organism and of two strains, one recovered from a blood culture vial and one from a coffee plant rhizosphere, both of which resembled strain LB400T in their whole-cell protein patterns. DNA-DNA hybridization experiments revealed that the three strains represented a single novel species, for which the name Burkholderia xenovorans sp. nov. is proposed. Strains of this novel species can be differentiated phenotypically from nearly all other Burkholderia species by their inability to assimilate L-arabinose. The whole-cell fatty acid profile of B. xenovorans strains is consistent with their classification in the genus Burkholderia, with 18 : 1omega7c, 16 : 1omega7c, 16 : 0, 14 : 0 3OH, 16 : 0 3OH, 17 : 0 cyclo and 14 : 0 being the most abundant fatty acids. The G + C content of the species varies between 62.4 and 62.9 mol%. The type strain of B. xenovorans is LB400T (= LMG 21463T = CCUG 46959T = NRRL B-18064T). PMID:15388727

  14. 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.

  15. Adamantyl-tethered-biphenylic compounds induce apoptosis in cancer cells by targeting Bcl homologs.

    PubMed

    Anusha, Sebastian; Mohan, Chakrabhavi Dhananjaya; Ananda, Hanumappa; Baburajeev, C P; Rangappa, Shobith; Mathai, Jessin; Fuchs, Julian E; Li, Feng; Shanmugam, Muthu K; Bender, Andreas; Sethi, Gautam; Basappa; Rangappa, Kanchugarakoppal S

    2016-02-01

    Bcl homologs prominently contribute to apoptotic resistance in cancer cells and serve as molecular targets in treatment of various cancers. Herein, we report the synthesis of biphenyl-adamantane derivatives by a ligand free palladium on carbon based Suzuki reaction using diisopropylamine as a base for the coupling of adamantane based aryl chloride with a variety of aryl boronic acids. Among the biphenyl derivatives synthesized, compound 3'-(adamantan-1-yl)-4'-methoxy-[1,1'-biphenyl]-3-ol (AMB) displayed cytotoxic activity against hepatocellular carcinoma cell lines without significantly affecting the normal cell lines. Further, AMB caused increased accumulation of the HCC cells in subG1 phase, decreased the expression of Bcl-2, Bcl-xL, cyclin D1, caspase-3, survivin and increased the cleavage of PARP in a time-dependent manner. In silico molecular interaction studies between Bcl homologs and AMB showed that the biphenyl scaffold is predicted to form π-π interactions with Phe-101 and Tyr-105 and the adamantyl fragment is predicted to occupy another hydrophobic region in the kink region of the binding groove. In summary, we report on the synthesis and biological characterization of adamantyl-tethered biphenylic compounds that induce apoptosis in tumor cells most likely by targeting Bcl homologs. PMID:26725030

  16. 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.

  17. 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.

  18. Involvement of plasmids in total degradation of chlorinated biphenyls

    SciTech Connect

    Furukawa, K.; Chakrabarty, A.M.

    1982-09-01

    Acinetobacter sp. stain P6 has previously been reported to utilize biphenyl (BP) and chlorinated BPs, with accumulation of corresponding chlorbenzoic acids. Arthrobacter sp. strain M5 was isolated as a contaminant in the culture of Acinetobacter sp. strain P6 growing on 4-chlorobiphenyl and showed properties similar to P6 in the degradation of chlorinated BPs. Both strains harbored an identical plasmid of 53.7 megadaltons. These strains spontaneously lost the ability to utilize BP and 4-chlorobiphenyl with high frequency (4 to 8%) after overnight growth in nutrient broth. The BP/sup -/ derivatives could not regain the BP-assimilating ability (reversion frequency, <10/sup -9/ per cell per generation) but retained the plasmid with small, detectable deletions. BP/sup +/ P6 cells grown on BP or benzoate oxidized BP and 2,3-dihydroxybiphenyl and produced meta cleavage compounds from the latter compound (lambda/sub max/, 434 nm) and also from catechol (lambda/sub max/, 375 nm) through the meta pathway. On the other hand, benzoate-grown BP/sup -/ segregants totally lost the BP-metabolizig activities and oxidized catechol through the ortho pathway. A combined culture of the chlorinated BP-dissimilating P6 or M5 strain (harboring the putative 53.7-megadalton plasmid specifying conversion of chlorobiphenyl to chlorobenzoic acids) and genetically constructed mono- or dichlorobenzoate-utilizing pseudomonads (harboring plasmids encoding complete utilization of mono- or dichlorobenzoates) allowed greater than 98% utilization of mono- and dichlorobiphenyls, with the liberation of equivalent amounts of chloride ions.

  19. 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. PMID:21863827

  20. Damaging effects of polychlorinated biphenyls on chicken primordial germ cells.

    PubMed

    Fang, Changge; Zhang, Caiqiao; Xia, Guoliang; Yang, Wei

    2002-01-01

    This work describes the effects of a commercial polychlorinated biphenyl (PCB) mixture, Aroclor 1254, as well as 17beta-oestradiol (E2) and testosterone on numbers and histomorphological changes of primordial germ cells (PGCs) in gonadal regions of Day 5 Hyline chicken embryos. The oestrogen receptor antagonist, clomiphen, alone or with PCBs was used in an attempt to protect the developing gonad from oestrogen-like effects of chemical PCBs. The results were as follows: (i) PCBs delayed embryonic development independently of dose (1 microg/egg, P<0.05; 10 microg/egg, P<0.01; 100 microg/egg, P<0.001 v. the control) and caused a dose-independent increase in mortality compared with the control group (10 microg/egg, P<0.01; 100 microg/egg, P<0.05); maximal mortality was observed in the 1 microg/egg group (P<0.001); (ii) PCBs decreased PGC numbers dose dependently (P<0.001) and caused a swollen nucleus with hyperchromatism (pyknosis) or cytoplasm vacuolation as signs of gonadal PGC degeneration in all PCB groups, or even complete disappearance in the 100 microg/egg group; (iii) after PCB treatment, the index of gonadal lesion increased significantly with the decrease of gonadal PGC number (1, 10 and 100 microg/egg, P<0.001); (iv) there were no observed effects of E2, testosterone and clomiphen on PGCs in the experiments; and (v) clomiphen failed to block the damaging effects of PCBs. These results suggest that the adverse effects of PCBs on chicken gonadal and germ cell development were initiated during the early stages of incubation through direct toxic effects, rather than through oestrogen-mimicking actions. As PGC numbers in the gonads decrease and the index of gonadal lesion increases, one may expect reproductive function to be compromised. PMID:12219939

  1. Human receptor activation by aroclor 1260, a polychlorinated biphenyl mixture.

    PubMed

    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

    2014-08-01

    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

  2. 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

  3. Formation and stability of polychlorinated biphenyl Pickering emulsions

    NASA Astrophysics Data System (ADS)

    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 ( ϕoil)=30 vol.%; solid concentration ( χ)=2 wt.%), the formed emulsions were indefinitely stable and the initial average droplet diameters varied from 80 to 258 μm, 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.

  4. 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

  5. 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. PMID:25945423

  6. 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

  7. 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

  8. 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

    2016-03-01

    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

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

    PubMed

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

    2010-11-30

    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

  10. 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.

  11. 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.

  12. Synthesis and Photophysical Properties of Biphenyl and Terphenyl Arylene–Ethynylene Macrocycles

    PubMed Central

    2015-01-01

    A series of single-walled carbon nanotube precursors, C3h-symmetric cyclotri(ethynylene)(biphenyl-2,4′-diyl) and cyclotri(ethynylene)(p-terphenyl-2,4″-diyl), have been prepared by a linear stepwise oligomerization–cyclization route and by statistical intermolecular cyclooligomerization. In addition to producing these members of a novel class of arylene ethynylene macrocycles, 1 and 2, the latter statistical process produces the smaller cyclic dimer, cyclodi(ethynylene)(p-terphenyl-2,4″-diyl) and the larger cyclic tetramer cyclotetra(ethynylene)(biphenyl-2,4′-diyl). These macrocycles display large Stokes shifts in their fluorescence spectra. Their biphenyl or terphenyl connectivity prevents these macrocycles from achieving full planarity in the ground state, and the ethynylene moieties could provide synthetic access to cyclic arylene oligomers and discrete carbon nanotube segments. PMID:24506215

  13. Hypochlorous acid-activated carbon: an oxidizing agent capable of producing hydroxylated polychlorinated biphenyls

    SciTech Connect

    Voudrias, E.A.; Larson, R.A.; Snoeyink, V.L.; Chen, A.S.C.; Stapleton, P.L.

    1986-11-01

    Granular activated carbon (GAC), in the presence of dilute aqueous hypochlorite solutions typical of those used in water treatment, was converted to a reagent capable of carrying out free-radical coupling reactions and other oxidations of dilute aqueous solutions of phenols. The products included biphenyls with chlorine and hydroxyl substitution (hydroxylated polychlorinated biphenyls). For example, 2,4-dichlorophenol, a common constituent of waste waters and also natural waters treated with hypochlorite, was converted to 3,5,5'trichloro-2,4'-dihydroxybiphenyl and several related compounds in significant amounts. It is possible that these products pose more of a health hazard than either the starting phenols or the unhydroxylated polychlorinated biphenyl derivatives.

  14. 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.

  15. 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

  16. 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. PMID:22464860

  17. Semiquinone Radicals from Oxygenated Polychlorinated Biphenyls: Electron Paramagnetic Resonance Studies

    PubMed Central

    2008-01-01

    Polychlorinated biphenyls (PCBs) can be oxygenated to form very reactive hydroquinone and quinone products. A guiding hypothesis in the PCB research community is that some of the detrimental health effects of some PCBs are a consequence of these oxygenated forms undergoing one-electron oxidation or reduction, generating semiquinone radicals (SQ•−). These radicals can enter into a futile redox cycle resulting in the formation of reactive oxygen species, that is, superoxide and hydrogen peroxide. Here, we examine some of the properties and chemistry of these semiquinone free radicals. Using electron paramagnetic resonance (EPR) to detect SQ•− formation, we observed that (i) xanthine oxidase can reduce quinone PCBs to the corresponding SQ•−; (ii) the heme-containing peroxidases (horseradish and lactoperoxidase) can oxidize hydroquinone PCBs to the corresponding SQ•−; (iii) tyrosinase acting on PCB ortho-hydroquinones leads to the formation of SQ•−; (iv) mixtures of PCB quinone and hydroquinone form SQ•− via a comproportionation reaction; (v) SQ•− are formed when hydroquinone-PCBs undergo autoxidation in high pH buffer (≈>pH 8); and, surprisingly, (vi) quinone-PCBs in high pH buffer can also form SQ•−; (vii) these observations along with EPR suggest that hydroxide anion can add to the quinone ring; (viii) H2O2 in basic solution reacts rapidly with PCB-quinones; and (ix) at near-neutral pH SOD can catalyze the oxidization of PCB-hydroquinone to quinone, yielding H2O2. However, using 5,5-dimethylpyrroline-1-oxide (DMPO) as a spin-trapping agent, we did not trap superoxide, indicating that generation of superoxide from SQ•− is not kinetically favorable. These observations demonstrate multiple routes for the formation of SQ•− from PCB-quinones and hydroquinones. Our data also point to futile redox cycling as being one mechanism by which oxygenated PCBs can lead to the formation of reactive oxygen species, but this is most efficient

  18. Rhodococcus biphenylivorans sp. nov., a polychlorinated biphenyl-degrading bacterium.

    PubMed

    Su, Xiaomei; Liu, Yindong; Hashmi, Muhammad Zaffar; Hu, Jinxing; Ding, Linxian; Wu, Min; Shen, Chaofeng

    2015-01-01

    A Gram-positive, aerobic, non-motile and rod-coccus shaped novel actinobacterial strain, designated as TG9(T), was isolated from a polychlorinated biphenyl (PCB)-contaminated sediment in Taizhou city, Zhejiang province, eastern China. The isolate was observed to grow at 10-45 °C (optimum 28-32 °C), pH 5.0-11.0 (optimum pH 7.0-8.0) and with 0-9.0 % (w/v) NaCl (optimum 0-3.0 %). Comparison of the 16S rRNA gene sequences of strain TG9(T) and other members of the genus Rhodococcus showed that strain TG9(T) shared highest similarities with Rhodococcus pyridinivorans DSM 44555(T) (99.4 %), R. rhodochrous DSM 43241(T) (99.2 %), R. gordoniae DSM 44689(T) (99.2 %) and R. artemisiae DSM 45380(T) (98.2 %). However, low levels of DNA-DNA relatedness (15-48 %), which are below the 70 % limit for prokaryotic species identification, were obtained by DNA-DNA hybridization. Strain TG9(T) was found to contain meso-diaminopimelic acid as the diagnostic diamino acid and arabinose and galactose in the whole-cell hydrolysate. Mycolic acids were found to be present. The major fatty acids were identified as C16:0, C16:1 ω7c and/or iso-C15:0 2-OH, 10-methyl C18:0 and C18:1 ω9c. The only menaquinone detected was MK-8 (H2). The major polar lipids detected were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, glycolipid and traces of some unknown lipids. The genomic DNA G+C content of strain TG9(T) was determined to be 62.8 %. The combined phenotypic and genotypic data show that the strain represents a novel species of the genus Rhodococcus for which the name Rhodococcus biphenylivorans sp. nov. is proposed, with the type strain TG9(T) (=CGMCC 1.12975(T) = KCTC 29673(T) = MCCC 1K00286(T)). PMID:25315102

  19. 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

  20. Conjugal Transfer of Polychlorinated Biphenyl/Biphenyl Degradation Genes in Acidovorax sp. Strain KKS102, Which Are Located on an Integrative and Conjugative Element

    PubMed Central

    Ishibashi, Yoko; Naganawa, Hideaki; Hirokawa, Satoshi; Atobe, Satomi; Nagata, Yuji; Tsuda, Masataka

    2012-01-01

    A polychlorinated biphenyl (PCB)/biphenyl degradation gene cluster in Acidovorax sp. strain KKS102, which is very similar to that in Tn4371 from Cupriavidus oxalaticus A5, was transferred to several proteobacterial strains by conjugation. The mobilized DNA fragment consisted of 61,807 bp and carried genes for mating-pair formation (mpf), DNA transfer (dtr), integrase (int), and replication-partition proteins (rep-parAB). In the transconjugants, transferred DNA was integrated at ATTGCATCAG or similar sequences. The circular-form integrative and conjugative element (ICE) was detected by PCR, and quantitative PCR analyses revealed that, in KKS102 cells, the ratio of the circular form to the integrated form was very low (approximately 10−5). The circular form was not detected in a mutant of the int gene, which was located at the extreme left and transcribed in the inward direction, and the level of int transcriptional activity was much higher in the circular form than in the integrated form. These findings clearly demonstrated that the genes for PCB/biphenyl degradation in KKS102 cells are located on an ICE, which was named ICEKKS1024677. Comparisons of similar ICE-like elements collected from the public database suggested that those of beta- and gammaproteobacteria were distinguishable from other ICE-like elements, including those in alphaproteobacteria, with respect to the gene composition and gene organization. PMID:22685277

  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. Laboratory study of polychlorinated biphenyls (PCB) transport from primary sources to building materials

    EPA Science Inventory

    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 servin...

  3. 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

  4. POLYCHLORINATED BIPHENYLS AS INDUCERS OF HEPATIC MICROSOMAL ENZYMES: STRUCTURE-ACTIVITY RULES

    EPA Science Inventory

    A number of highly purified polychlorinated biphenyl (PCB) isomers and congeners were synthesized and administered to male Wistar rats at dosage levels of 30 and 150 micromol/kg. The effects of this in vivo treatment on the drug-metabolizing enzymes were determined by measuring t...

  5. POLYCHLORINATED BIPHENYLS AS INDUCERS OF HEPATIC MICROSOMAL ENZYMES: EFFECTS OF DI-ORTHO SUBSTITUTION

    EPA Science Inventory

    All of the 13 possible polychlorinated biphenyl (PCB) isomers and congeners substituted at both para positions, at least two meta positions (but not necessarily on the same ring) and at two ortho positions have been synthesized and tested as rat hepatic microsomal enzyme inducers...

  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. 75 FR 4759 - Polychlorinated Biphenyls: Manufacturing (Import) Exemption for Veolia ES Technical Solutions, LLC

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-29

    ..., LLC, which was published in the Federal Register on March 6, 2008 (73 FR 12053). In addition to... Federal Register notice for the hearing (73 FR 28786, May 19, 2008). In addition to all of the pre... of polychlorinated biphenyl (PCB) waste from Mexico for disposal at Veolia's TSCA-approved...

  8. 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...

  9. 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...

  10. POLYCHLORINATED BIPHENYL (AROCLOR 1254) INDUCED NEPHROTOXICITY, CHANGES IN FEMUR MORPHOMETRY AND CALCIUM METABOLISM

    EPA Science Inventory

    Experiments were performed to investigate the effects of polychlorinated biphenyl (PCB) on calcium metabolism, femur morphometry, and nephrotoxicity. ischer 344 rats Here dosed daily 1G for 5, 10 or 15 weeks with 0, 0.1, 1, 10 or 25 mg PCB/kg body weight. fter 5, 10 and 15 weeks,...

  11. Chamber study of polychlorinated biphenyl (PCB)emissions from caulking materials and light ballasts

    EPA Science Inventory

    The emissions of polychlorinated biphenyl (PCB) congeners from 13 caulk samples were tested in a micro-chamber system. Twelve samples were from PCB-contaminated buildings and one was prepared in the laboratory. Nineteen light ballasts collected from buildings that represent 13 di...

  12. Chamber study of polychlorinated biphenyl (PCB) emissions from caulking materials and light ballasts

    EPA Science Inventory

    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 servin...

  13. Chamber study of polychlorinated biphenyl {PCB} emissions from caulking materials and light ballasts

    EPA Science Inventory

    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 servin...

  14. 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 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.)

  15. 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...

  16. 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...

  17. Extensive degradation of aroclors and environmentally transformed polychlorinated biphenyls by Alcaligenes eutrophus H850

    SciTech Connect

    Bedard, D.L.; Wagner, R.E.; Brennan, M.J.; Haberl, M.L.; Brown, J.F. Jr.

    1987-05-01

    The authors have isolated and characterized a strain of Alcaligenes eutrophus, designated H850, that rapidly degrades a broad and unusual spectrum of polychlorinated biphenyls (PCBs) including many tetra- and pentachlorobiphenyls and several hexachlorobiphenyls. This strains, which was isolated from PCB-containing dredge spoils by enrichment on biphenyl, grows well on biphenyl and 2-chlorobiphenyl but poorly on 3- and 4-chlorobiphenyl. Capillary gas-chromatographic analysis showed that biphenyl-grown resting cells of H850 degraded the components of 38 of the 41 largest peaks of Aroclor 1242 and 15 of the 44 largest peaks of Aroclor 1254, resulting in an overall reduction of PCBs by 81% for Aroclor 1242 (10 ppm) and 35% for the Aroclor 1254 (10 ppm) in 2 days. Furthermore, H850 metabolized the predominantly ortho-substituted PCB congeners that the resulted from the environmental transformation of the more highly chlorinated congeners of Aroclor 1242 by the upper Hudson River anaerobic meta-, and para-dechlorination agent system. The congener selectivity patterns indicate that a two-step process consisting of anaerobic dechlorination followed by oxidation by H850 can effectively degrade all to congeners in Aroclor 1242 and possibly all those in Aroclor 1254.

  18. 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...

  19. 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...

  1. COMPARATIVE EFFECTS OF TWO POLYCHLORINATED BIPHENYL CONGENERS ON CALCIUM HOMEOSTASIS IN RAT CEREBELLAR GRANULE CELLS

    EPA Science Inventory

    Some polychlorinated biphenyls (PCBs) have been reported to alter locomotor activity and decrease brain dopamine function in laboratory animals. CBs with orth- and/or para-chlorine substitutions are reportedly most potent in decreasing cell dopamine content in vitro and were dete...

  2. 21 CFR 509.30 - Temporary tolerances for polychlorinated biphenyls (PCB's).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Temporary tolerances for polychlorinated biphenyls (PCB's). 509.30 Section 509.30 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... FOOD AND FOOD-PACKAGING MATERIAL Tolerances for Unavoidable Poisonous or Deleterious Substances §...

  3. 21 CFR 509.30 - Temporary tolerances for polychlorinated biphenyls (PCB's).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Temporary tolerances for polychlorinated biphenyls (PCB's). 509.30 Section 509.30 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS UNAVOIDABLE CONTAMINANTS IN ANIMAL FOOD AND FOOD-PACKAGING MATERIAL...

  4. 21 CFR 509.30 - Temporary tolerances for polychlorinated biphenyls (PCB's).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Temporary tolerances for polychlorinated biphenyls (PCB's). 509.30 Section 509.30 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... FOOD AND FOOD-PACKAGING MATERIAL Tolerances for Unavoidable Poisonous or Deleterious Substances §...

  5. 21 CFR 509.30 - Temporary tolerances for polychlorinated biphenyls (PCB's).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Temporary tolerances for polychlorinated biphenyls (PCB's). 509.30 Section 509.30 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... FOOD AND FOOD-PACKAGING MATERIAL Tolerances for Unavoidable Poisonous or Deleterious Substances §...

  6. 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...

  7. SOURCES OF EMISSIONS OF POLYCHLORINATED BIPHENYLS INTO THE AMBIENT ATMOSPHERE AND INDOOR AIR

    EPA Science Inventory

    Polychlorinated biphenyls (PCB) have been identified in air samples from many parts of the world since 1960s. This study was undertaken to identify and compare different sources of PCB in indoor and outdoor air. All sampling was performed in central North Carolina. The suspected ...

  8. 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...

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

    USGS Publications Warehouse

    Noguchi, G.E.

    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.

  10. 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...

  11. TOXICITY OF POLYCHLORINATED BIPHENYLS (PCB'S) TO FISH AND OTHER AQUATIC LIFE

    EPA Science Inventory

    Polychlorinated biphenyls (PCB's) have been shown to be widespread in the environment. Their significance in the aquatic environment as a poison is now being revealed. They are being detected in fish and other aquatic life at levels much higher than concentrations found in the wa...

  12. 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)...

  13. A METHOD FOR THE SAMPLING AND ANALYSIS OF POLYCHLORINATED BIPHENYLS (PCBS) IN AMBIENT AIR

    EPA Science Inventory

    A method was developed for the sampling and analysis of polychlorinated biphenyls (PCBs) in air. An easily constructed, high-volume sampling system is employed with porous polyurethane foam as the collection medium. The sample is collected at the rate of 0.6 to 1.0 cu m per minut...

  14. SENSITIVITY OF ADENOSINE TRIPHOSPHATASE IN DIFFERENT BRAIN REGIONS TO POLYCHLORINATED BIPHENYL CONGENERS

    EPA Science Inventory

    Polychlorinated biphenyl (PCBs) mixtures contain a number of different congeners, some of which have been proposed to be neuroactive. Recent studies have suggested that ortho-substituted PCBs may be neuroactive, while "dioxin-like" non-ortho-substituted congeners are not. This st...

  15. 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...

  16. GREAT LAKES ECOSYSTEM - MODELING OF THE FATE OF PCBS (POLYCHLORINATED BIPHENYLS)

    EPA Science Inventory

    The report defines the Polychlorinated biphenyl (PCB) problem in the Great Lakes, describes how they got there, describes models of: (1) physical/chemical fate generally; and, (2) specifically, fate of PCBs in aquatic ecosystems. Theory, data and model results are given. Also add...

  17. 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

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

    PubMed

    Pham, Thi Thanh My; Sondossi, Mohammad; Sylvestre, Michel

    2015-07-01

    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 picture of the fate of polychlorinated

  19. Enhanced biodegradation of polychlorinated biphenyls in soil by analog enrichment and bacterial inoculation

    SciTech Connect

    Brunner, W.; Sutherland, F.H.; Focht, D.D.

    1985-01-01

    Carbon-14-labeled polychlorinated biphenyls (PBC) representing the commercial Aroclor 1242 mixture (a mixture of chlorinated biphenyls) were incubated in soil over a 210-d period to determine if biodegradation could be enhanced by additions of straw and sludge, aerobic and anaerobic incubations, or combinations thereof. Although PCB (100 mg/kg) had no effect on microbial respiratory processes in soil, mineralization did not exceed 3% of the total added. Also, neither /sup 14/CO/sub 2/ nor /sup 14/CH/sub 4/ was produced from anaerobic incubations, although both gases were produced from organic matter additions. Further experimentation was undertaken to investigate the possibility that the soil lacked either an indigenous microflora capable of metabolizing PCB or a suitable substrate analog which promoted their activity or growth. Inoculation with Acintobacter P6 (Furukawa) alone did not enhance mineralization of /sup 14/C-PCB. However, when enriched with substrate analog biphenyl, 20 to 27% of the label was recovered as /sup 14/CO/sub 2/ over a 63-d period compared to < 1% /sup 14/CO/sub 2/ for the unenriched controls. Uninoculated and enriched treatments also greatly enhanced mineralization yielding 15 to 20% as /sup 14/CO/sub 2/, yet the extent of primary degradation of PCB (i.e., disappearance) was greater when both Acinetobacter and biphenyl were added. Analog enrichment with biphenyl is the most important factor effecting PCB degradation in soil, but additional enhancement is brought about by inoculation with Acinetobacter, which is superior to the indigenous microflora with respect to diversity towards metabolism of the isomers present in Aroclor 1242.

  20. 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

  1. 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

  2. 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 (...

  3. AVAILABILITY OF PCBS (POLYCHLORINATED BIPHENYLS) AND PAHS (POLYCYCLIC AROMATIC HYDROCARBONS) TO 'MYTILUJ EDULIS' FROM ARTIFICIALLY RESUSPENDED SEDIMENTS

    EPA Science Inventory

    Estuarine sediment containing high levels of polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) was resuspended into a flowing seawater system. Analysis of the dissolved and particulate phases in the exposure tank indicated a release of some low molecula...

  4. 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...

  5. 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 ...

  6. Spatial distribution and ecological risk of polychlorinated biphenyls in sediments from Qinzhou Bay, Beibu Gulf of South China.

    PubMed

    Zhang, Jinlian; Li, Yuanyuan; Wang, Yinghui; Zhang, Yuanyuan; Zhang, Dan; Zhang, Ruijie; Li, Jun; Zhang, Gan

    2014-03-15

    The residual level of polychlorinated biphenyls (PCBs) was determined in the surface sediments collected from the Qinzhou Bay, Beibu Gulf of Southern China. The results showed that the total concentration of PCBs ranged from 1.62 to 62.63 ng/g dry wt, with a mean of 9.87 ng/g dry wt. Generally, the average PCBs concentrations in three sample groups descended in this order: inner bay > outer bay > rivers. On a mean level, with respect to the PCBs homologue profiles, the analysis suggested that tetrachlorinated biphenyls was the most abundant PCB, followed by hexachlorinated biphenyls, pentachlorinated biphenyls. PCB profiles varied according to the nature of the site and its proximity to the sources. PCA with multiple linear regression analysis indicated that Aroclor products contributed to the PCBs in Qinzhou Bay. Risk assessments conducted on the levels indicated that PCBs in sediments of Qinzhou Bay posed no significant risk to human health. PMID:24380702

  7. 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,...

  8. DIFFERENTIAL EFFECTS OF POLYCHLORINATED BIPHENYL CONGENERS ON PHOSPHOINOSITIDE HYDROLYSIS AND PROTEIN KINASE C TRANSLOCATION IN RAT CEREBELLAR GRANULE CELLS

    EPA Science Inventory

    Previous reports from our laboratory have suggested that the neuroactivity of some polychlorinated biphenyl (PCB) congeners is associated with perturbations in cellular Ca2+-homeostasis. o characterize the neurochemical effects of PCBs further, the present experiments found that ...

  9. Characterization of the metabolic pathway and catabolic gene expression in biphenyl degrading marine bacterium Pseudomonas aeruginosa JP-11.

    PubMed

    Chakraborty, Jaya; Das, Surajit

    2016-02-01

    Metabolic pathway of biphenyl assimilation and the catabolic gene expression in a marine bacterium Pseudomonas aeruginosa JP-11, isolated from the coastal sediments of Odisha, India have been studied. This strain utilized 98.86% ± 2.29% of biphenyl within 72 h when supplied as the sole source of carbon, however, preferential utilization of glucose was observed over catechol and biphenyl when grown in a complex medium. Combination of chromatographic and spectrophotometric techniques confirmed the catechol pathway and identified 2-Hydroxy-6-oxo-6-phenylhexa-2, 4-dienoate as the intermediate metabolic product. Assimilation of biphenyl was initiated by its dioxygenation, forming cis-2, 3-dihydro-2, 3-dihydroxybiphenyl subsequently transformed to 2-hydroxy-6-oxo-6-phenylhexa-2, 4-dienoate. In the lower pathway, cis-1, 6-dihydroxy-2, 4-cyclohexadiene-1-carboxylic acid was detected which formed catechol before entering into the Krebs cycle. Detection of key enzyme catechol-1, 2-dioxygenase in the cell-free extract of P. aeruginosa JP-11 supported the proposed degradation pathway. The primary enzyme for biphenyl assimilation, biphenyl dioxygenase encoded by bphA gene was found in the genome of the isolate. On increasing biphenyl stress (50, 100, 150 and 200 mg L(-1)), bphA gene showed a significant (P < 0.01) up-regulation upto 43.5 folds. Production of biosurfactant was confirmed and the rhamnolipid synthesizing gene rhlAB was amplified. This gene also showed a significant (P < 0.01) up-regulation upto 258 folds on increasing biphenyl stress. PMID:26519802

  10. The determination of polychlorinated biphenyl residues: a review with special reference to foods.

    PubMed

    Robards, K

    1990-01-01

    The determination of polychlorinated biphenyls presents several unique analytical problems, not least of which is the need to identify and quantify 209 possible analytes. Moreover, congener-specific analysis is essential because of structure-activity effects on toxicity and environmental stability. Although significant advances have been achieved in identification/quantification procedures with the aid of highly efficient, inert open tubular chromatography columns and coupled GC-MS, sampling and extraction procedures have not developed to the same extent. The primary focus of this review is the determination of polychlorinated biphenyls in foods. However, the problems of separation and identification overshadow the importance of the sample matrix, and relevant data from other areas of analysis are quoted. PMID:2113010

  11. Remarkably diastereoselective synthesis of a chiral biphenyl diphosphine ligand and its application in asymmetric hydrogenation

    PubMed Central

    Qiu, Liqin; Wu, Jing; Chan, Shusun; Au-Yeung, Terry T.-L.; Ji, Jian-Xin; Guo, Rongwei; Pai, Cheng-Chao; Zhou, Zhongyuan; Li, Xingshu; Fan, Qing-Hua; Chan, Albert S. C.

    2004-01-01

    Essentially complete atropdiastereoselectivity was realized in the preparation of biaryl diphosphine dioxide by asymmetric intramolecular Ullmann coupling and oxidative coupling with central-to-axial chirality transfer. A bridged C2-symmetric biphenyl phosphine ligand possessing additional chiral centers on the linking unit of the biphenyl groups was synthesized. No resolution step was required for the preparation of the enantiomerically pure chiral ligand. These findings offer a general and practical tool for the development of previously uninvestigated atropdiastereomeric biaryl phosphine ligands. The diphosphine ligand was found to be highly effective in the asymmetric hydrogenation of α- and β-ketoesters, 2-(6′-methoxy-2′-naphthyl)propenoic acid, β-(acylamino)acrylates, and enol acetates. PMID:15067137

  12. Modulating inhibitors of transthyretin fibrillogenesis via sulfation: polychlorinated biphenyl sulfates as models.

    PubMed

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

    2015-02-25

    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

  13. Evaluation of fluorinated biphenyl ether pro-drug scaffolds employing the chemical-microbial approach.

    PubMed

    Hampton, Alex S; Mikulski, Lena; Palmer-Brown, William; Murphy, Cormac D; Sandford, Graham

    2016-05-01

    Incorporation of fluorine in a drug can dramatically affect its metabolism and methods to assess the effect of fluorine substitution on drug metabolism are required for effective drug design. Employing a previously developed chemical-microbial method the metabolism of a series of fluorinated biphenyl ethers was determined. The substrates were synthesized via Ullmann-type condensation reactions between bromotoluene and fluorophenol. The ethers were incubated with the fungus Cunninghamella elegans, which oxidises xenobiotics in an analogous fashion to mammals, generating a number of hydroxylated biphenyl ethers and acids. The propensity of the fluorinated ring to be hydroxylated depended upon the position of the fluorine atom, and the oxidation of the methyl group was observed when it was meta to the oxygen. The experiments demonstrate the applicability of the method to rapidly determine the effect of fluorine substitution on CYP-catalysed biotransformation of pro-drug molecules. PMID:27020303

  14. Reductive microbial dechlorination of indigenous polychlorinated biphenyls in soil using a sediment-free inoculum.

    PubMed

    Klasson, K T; Barton, J W; Evans, B S; Reeves, M E

    1996-01-01

    In laboratory experiments, unagitated soil slurry bioreactors inoculated with micro-organisms extracted from polychlorinated biphenyl-contaminated (PCBs) sediments from the Hudson River were used to anaerobically dechlorinate PCBs. The onset of dechlorination activity was accelerated by the addition of certain organic acids (pyruvate and maleate) and single congeners (2,3,6-trichlorobiphenyl). Dechlorination was observed under several working conditions after 19 weeks of incubation with PCB-contaminated soil and nutrient solution. Best results showed a drop in average chlorine content from 4.3 to 3.6 chlorines per biphenyl due to a loss of m-chlorines. Soil used for these experiments was obtained from a PCB-contaminated (weathered Aroclor 1248) site at an electric power substation. Dechlorination was observed with no sediment particles or other matrix being added. PMID:8652118

  15. 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.

  16. Reductive microbial dechlorination of indigenous polychlorinated biphenyls in soil using a sediment-free inoculum

    SciTech Connect

    Klasson, K.T.; Barton, J.W.; Evans, B.S.; Reeves, M.E.

    1996-05-01

    In laboratory experiments, unagitated soil slurry bioreactors inoculated with microorganisms extracted from polychlorinated biphenyl-contaminated (PCBs) sediments from the Hudson River were used to anaerobically dechlorinate PCBs. The onset of dechlorination activity was accelerated by the addition of certain organic acids (pyruvate and maleate) and single congeners (2,3,6-trichlorobiphenyl). Dechlorination was observed under several working conditions after 19 weeks of incubation with PCB-contaminated soil and nutrient solution. Best results showed a drop in average chlorine content from 4.3 to 3.6 chlorines per biphenyl due to a loss of m-chlorines. Soil used for these experiments was obtained from a PCB-contaminated (weathered Aroclor 1248) site at an electric power substation. Dechlorination was observed with no sediment particles or other matrix being added. 17 refs., 6 figs., 1 tab.

  17. 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

  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. PMID:23910395

  19. Metabolism of chlorobiphenyls by a variant biphenyl dioxygenase exhibiting enhanced activity toward dibenzofuran

    SciTech Connect

    Viger, Jean-Francois; Mohammadi, Mahmood; Barriault, Diane; Sylvestre, Michel

    2012-03-09

    Highlights: Black-Right-Pointing-Pointer Burkholderia xenovorans LB400 biphenyl dioxygenase (BphAE{sub LB400}) metabolizes PCBs. Black-Right-Pointing-Pointer Asn338Gln/Leu409Phe double mutation speeds up electron transfer of enzyme reaction. Black-Right-Pointing-Pointer We tested how the mutations affect the PCB-degrading abilities of BphAE{sub LB400} variants. Black-Right-Pointing-Pointer The same mutations also broaden the PCB substrate range of BphAE{sub LB400} variants. -- Abstract: The biphenyl dioxygenase of Burkholderia xenovorans LB400 (BphAE{sub LB400}) catalyzes the dihydroxylation of biphenyl and of several polychlorinated biphenyls (PCBs) but it poorly oxidizes dibenzofuran. In this work we showed that BphAE{sub RR41}, a variant which was previously found to metabolize dibenzofuran more efficiently than its parent BphAE{sub LB400}, metabolized a broader range of PCBs than BphAE{sub LB400}. Hence, BphAE{sub RR41} was able to metabolize 2,6,2 Prime ,6 Prime -, 3,4,3 Prime ,5 Prime - and 2,4,3 Prime ,4 Prime -tetrachlorobiphenyl that BphAE{sub LB400} is unable to metabolize. BphAE{sub RR41} was obtained by changing Thr335Phe336Asn338Ile341Leu409 of BphAE{sub LB400} to Ala335Met336Gln338Val341Phe409. Site-directed mutagenesis was used to create combinations of each substitution, in order to assess their individual contributions. Data show that the same Asn338Glu/Leu409Phe substitution that enhanced the ability to metabolize dibenzofuran resulted in a broadening of the PCB substrates range of the enzyme. The role of these substitutions on regiospecificities toward selected PCBs is also discussed.

  20. 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.

  1. 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.

  2. (Biphenyl-2-yl)bromidobis(2-methyl-tetra-hydro-furan-κO)magnesium(II).

    PubMed

    Nordschild, Simon; Wohlgemuth, D; Bolte, Michael

    2009-01-01

    In the title Grignard reagent, [MgBr(C(12)H(9))(C(5)H(10)O)(2)], the Mg centre adopts a distorted tetra-hedral MgCO(2)Br arrangement. The dihedral angle between the two aromatic rings of the biphenyl residue is 44.00 (14)°. Each mol-ecule incorporates one R- and one S-configured 2-methyl-tetra-hydro-furan mol-ecule. PMID:21583743

  3. [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. PMID:26299864

  4. Antiproliferative and pro-apoptotic activity of eugenol-related biphenyls on malignant melanoma cells

    PubMed Central

    Pisano, Marina; Pagnan, Gabriella; Loi, Monica; Mura, Maria Elena; Tilocca, Maria Giovanna; Palmieri, Giuseppe; Fabbri, Davide; Dettori, Maria Antonietta; Delogu, Giovanna; Ponzoni, Mirco; Rozzo, Carla

    2007-01-01

    Background Malignant melanoma is one of the most aggressive skin cancer and chemotherapeutic agents currently in use are still unsatisfactory. Prevention and early diagnosis are the only effective tools against this tumour whose incidence and mortality rates are highly increased during the last decades in fair skin populations. Therefore the search for novel therapeutic approaches is warranted. Aim of this work was to identify and test new compounds with antiproliferative and cytotoxic activity on melanoma cells. We tested eugenol together with six natural and synthetic eugenol-related compounds for their capability to inhibit cell growth on primary melanoma cell lines established from patients' tissue samples. Results Eugenol and isoeugenol monomers and their respective O-methylated forms did not show to inhibit melanoma cells proliferation. Conversely, the dimeric forms (biphenyls) showed some antiproliferative activity which was mild for dehydrodieugenol, higher for its O,O'-methylated form (O,O'-dimethyl-dehydrodieugenol), and markedly pronounced for the racemic mixture of the brominated biphenyl (6,6'-dibromo-dehydrodieugenol) (S7), being its enantiomeric form (S) the most effective compared to the other compounds. Such activity resulted to be selective against tumour cells, without affecting cultured normal human skin fibroblasts. Dose and time dependence curves have been obtained for the enantiomeric form S7-(S). Then IC50 and minimal effective doses and times have been established for the melanoma cell lines tested. TUNEL and phosphatidylserine exposure assays demonstrated the occurrence of apoptotic events associated with the antiproliferative activity of S7-(S). Cytotoxic activity and apoptosis induced by treating melanoma cells with eugenol-related biphenyls was partially dependent by caspase activation. Conclusion Our findings demonstrate that the eugenol related biphenyl (S)-6,6'-dibromo-dehydrodieugenol elicits specific antiproliferative activity on

  5. 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.

  6. Polychlorinated biphenyls (PCBs) and polybrominated biphenyl ethers (PBDEs) in environmental samples from Ny-Ålesund and London Island, Svalbard, the Arctic.

    PubMed

    Zhu, Chaofei; Li, Yingming; Wang, Pu; Chen, Zhaojing; Ren, Daiwei; Ssebugere, Patrick; Zhang, Qinghua; Jiang, Guibin

    2015-05-01

    Polychlorinated biphenyls (PCBs) and polybrominated biphenyl ethers (PBDEs) were determined in environmental samples collected from Ny-Ålesund and London Island, Svalbard, the Arctic. Total PCB concentrations (∑25PCBs) varied from 0.57 to 2.52 ng g(-1) dry weight (dw) in soil, 0.30 to 1.16 ng g(-1) dw in plants and 0.56 to 0.98 ng g(-1) dw in reindeer dung. The non-Aroclor congener of CB-11 was predominant in most samples compared to other congeners, accounting for 16.0±9.8% to the ∑25PCBs. The ∑13PBDEs concentrations were 1.7-416, 36.7-495 and 28.1-104 pg g(-1) dw in soil, plants and reindeer dung, respectively. The signature of enantioselective biotransformation was observed in all samples for chiral CB-95, whereas in parts of samples for other chiral PCBs. Bioaccumulation factors (BAFs) in six plant species varied within individual contaminant congeners and plant species, with BAFs less than 1 for ∑PCBs and higher than 1 for ∑PBDEs. BAF values decreased with increasing soil concentrations, suggesting that high background levels in soil restricted the accumulation of these contaminants by plants. PMID:25697952

  7. 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.

  8. Nano/bio treatment of polychlorinated biphenyls with evaluation of comparative toxicity

    DOE PAGESBeta

    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 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

  9. 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.

  10. Benzanilide–Biphenyl Replacement: A Bioisosteric Approach to Quinoline Carboxamide-Type ABCG2 Modulators

    PubMed Central

    2013-01-01

    Recently reported compounds such as UR-COP78 (6) are among the most potent and selective ABCG2 modulators known so far but are prone to rapid enzymatic cleavage at the central benzanilide moiety. In search for more stable analogues, according to a bioisosteric approach, a series of N-(biphenyl-3-yl)quinoline carboxamides was prepared by solid phase and solution phase synthesis. The biphenyl moiety was constructed by Suzuki coupling. Inhibition of ABCB1 and ABCG2 was determined in a calcein-AM and a Hoechst 33342 microplate assay, respectively. Most synthesized compounds selectively inhibited the ABCG2 transporter at submicromolar concentrations with a maximal inhibitory effect (Imax) over 90% (e.g., UR-COP228 (22a), IC50 591 nM, Imax 109%; UR-COP258 (31), IC50 544 nM, Imax 112%), though with lower potency and selectivity than 6. The biphenyl analogues are considerably more stable and demonstrate that the benzanilide core is not a crucial structural feature of quinoline carboxamide-type ABCG2 modulators. PMID:24900683

  11. 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.

  12. A clinical and electrophysiological study of patients with polychlorinated biphenyl poisoning.

    PubMed Central

    Chia, L G; Chu, F L

    1985-01-01

    Neurological examination of 28 patients, 4 years after serious poisoning by polychlorinated biphenyl contaminated cooking oil, are compared with similar examinations of the same patients two years earlier (in 1980). Clinical peripheral sensory neuropathy was found in 54%, headache in 36% and dizziness in 46% of the patients; these findings did not differ (p greater than 0.1) from those in 1980. Although the mean blood polychlorinated biphenyl concentration (19.2 ppb) in the patients was lower (p less than 0.001) than that in 1980 (35.9 ppb), it was still higher than the normal value (less than 4 ppb). There was no difference in the blood polychlorinated biphenyl concentration of patients with neurological manifestation from those without. Although the mean motor and sensory nerve conduction velocities (MNCV and SNCV) were still slower (p less than 0.06) than the mean normal NCV, the mean MNCV of tibial nerve and SNCV of sural nerve were improved (p less than 0.06) as compared with those in 1980. EEGs were normal except in two cases showing nonspecific slow wave changes. In addition, evoked potentials (somatosensory, visual and brain-stem auditory) were measured in this study and found to be normal in all 12 cases examined. PMID:2995592

  13. 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

  14. Interconversion between Methoxylated and Hydroxylated Polychlorinated Biphenyls in Rice Plants: An Important but Overlooked Metabolic Pathway.

    PubMed

    Sun, Jianteng; Pan, Lili; Su, Zhenzhu; Zhan, Yu; Zhu, Lizhong

    2016-04-01

    To date, there is limited knowledge on the methoxylation of polychlorinated biphenyls (PCBs) and the relationship between hydroxylated polychlorinated biphenyls (OH-PCBs) and methoxylated polychlorinated biphenyls (MeO-PCBs) in organisms. In this study, rice (Oryza sativa L.) was chosen as the model organism to determine the metabolism of PCBs in plants. Limited para-substituted 4'-OH-CB-61 (major metabolite) and 4'-MeO-CB-61 (minor metabolite) were found after a 5-day exposure to CB-61, while ortho- and meta-substituted products were not detected. Interconversion between OH-PCBs and MeO-PCBs in organisms was observed for the first time. The demethylation ratio of 4'-MeO-CB-61 was 18 times higher than the methylation ratio of 4'-OH-CB-61, indicating that formation of OH-PCBs was easier than formation of MeO-PCBs. The transformation products were generated in the roots after 24 h of exposure. The results of in vivo and in vitro exposure studies show that the rice itself played a key role in the whole transformation processes, while endophytes were jointly responsible for hydroxylation of PCBs and demethylation of MeO-PCBs. Metabolic pathways of PCBs, OH-PCBs, and MeO-PCBs in intact rice plants are proposed. The findings are important in understanding the fate of PCBs and the source of OH-PCBs in the environment. PMID:26928534

  15. Toxicity of hydroxylated polychlorinated biphenyls (HO-PCBs) using the bioluminescent assay Microtox(®).

    PubMed

    Bhalla, Renu; Tehrani, Rouzbeh; Van Aken, Benoit

    2016-09-01

    Hydroxylated polychlorinated biphenyls (HO-PCBs) are toxic contaminants which are produced in the environment by biological or abiotic oxidation of PCBs. The toxicity of a suite of 23 mono-hydroxylated derivatives of PCBs and 12 parent PCBs was determined using the bacterial bioluminescent assay Microtox(®). All HO-PCBs tested exhibited higher toxicity than the corresponding parent PCB, with effect concentration 50 % (EC50) ranging from 0.07 to 133 mg L(-1). The highest toxicities were recorded with 4-hydroxylated derivatives of di-chlorinated biphenyls (EC50 = 0.07-0.36 mg L(-1)) and 2-hydroxylated derivatives of tri-chlorinated biphenyls carrying a chlorine substituent on the phenolic ring (EC50 = 0.34-0.48 mg L(-1)). The toxicity of HO-PCBs generally decreased when the degree of chlorination increased. Consistently with this observation, a significant positive correlation was measured between toxicity (measured by EC50) and octanol-water partition coefficient (pK ow) for the HO-PCBs under study (Pearson's correlation coefficient, r = 0.74), which may be explained by the lower solubility and bioavailability generally associated with higher hydrophobicity. This study is the first one which assessed the toxicity of a suite of PCBs and HO-PCBs using the bioluminescent assay Microtox(®), showing an inverse correlation between toxicity and hydrophobicity. PMID:27411941

  16. 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

  17. 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.

  18. 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

  19. Differential expression of biphenyl synthase gene family members in fire-blight-infected apple 'Holsteiner Cox'.

    PubMed

    Chizzali, Cornelia; Gaid, Mariam M; Belkheir, Asma K; Hänsch, Robert; Richter, Klaus; Flachowsky, Henryk; Peil, Andreas; Hanke, Magda-Viola; Liu, Benye; Beerhues, Ludger

    2012-02-01

    Fire blight, caused by the bacterium Erwinia amylovora, is a devastating disease of apple (Malus × domestica). The phytoalexins of apple are biphenyls and dibenzofurans, whose carbon skeleton is formed by biphenyl synthase (BIS), a type III polyketide synthase. In the recently published genome sequence of apple 'Golden Delicious', nine BIS genes and four BIS gene fragments were detected. The nine genes fall into four subfamilies, referred to as MdBIS1 to MdBIS4. In a phylogenetic tree, the BIS amino acid sequences from apple and Sorbus aucuparia formed an individual cluster within the clade of the functionally diverse type III polyketide synthases. cDNAs encoding MdBIS1 to MdBIS4 were cloned from fire-blight-infected shoots of apple 'Holsteiner Cox,' heterologously expressed in Escherichia coli, and functionally analyzed. Benzoyl-coenzyme A and salicoyl-coenzyme A were the preferred starter substrates. In response to inoculation with E. amylovora, the BIS3 gene was expressed in stems of cv Holsteiner Cox, with highest transcript levels in the transition zone between necrotic and healthy tissues. The transition zone was the accumulation site of biphenyl and dibenzofuran phytoalexins. Leaves contained transcripts for BIS2 but failed to form immunodetectable amounts of BIS protein. In cell cultures of apple 'Cox Orange,' expression of the BIS1 to BIS3 genes was observed after the addition of an autoclaved E. amylovora suspension. Using immunofluorescence localization under a confocal laser-scanning microscope, the BIS3 protein in the transition zone of stems was detected in the parenchyma of the bark. Dot-shaped immunofluorescence was confined to the junctions between neighboring cortical parenchyma cells. PMID:22158676

  20. 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

  1. 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.

  2. Residues of organochlorine pesticides and polychlorinated biphenyls and autopsy data for bald eagles, 1973-74.

    PubMed

    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

    1977-12-01

    Eighty-six bald eagles found sick or dead during 1973-74 in 24 States were analyzed for organochlorine compounds. DDE was detected in all caracasses; polychlorinated biphenyls (PCB's) were found in all but two. Seventy-five carcasses contained TDE and/or dieldrin. Four eagles had possibly lethal levels of dieldrin in the brain. Bald eagles continue to retain high residue levels of organochlorine pollutants. Illegal shooting remained the most common cause of death but accounted for a smaller percentage of the mortalities than in the two previous biennial collections. PMID:416416

  3. 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.

  4. 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.

  5. 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.

  6. Dechlorination of polychlorinated biphenyls: A kinetic study of removal of PCBs from mineral oils

    SciTech Connect

    Filippis, P. de; Scarsella, M.; Pochetti, F.

    1999-02-01

    A kinetic study was done of the dechlorination of polychlorinated biphenyls (PCBs) eliminated from contaminated dielectric oils by using the potassium poly(ethylene glycolate) (KPEG) process. Experimental runs at laboratory scale showed that the kinetics of the removal reaction was first-order for each PCB present and first-order with respect to the KPEG concentration. The PCB elimination grade was also affected by the KOH/PEG ratio. An exponential correlation was found between the kinetic constant for each congener and its respective gas chromatographic relative retention time.

  7. Rapid separation of polychlorinated biphenyls from DDT and its analogues on silica gel

    USGS Publications Warehouse

    Snyder, Diane; Reinert, Robert E.

    1971-01-01

    Polychlorinated biphenyls (PCB's), which are used in industry worldwide (i), have been found as residues in numerous wildlife species (2-7). Because of the similarity in chemical characteristics, PCB compounds interfere with gas liquid chromatographic (GLC) analysis of certain chlorinated hydrocarbon insecticides (8). In the present study, we sought a rapid microanalytical procedure for separation of PCB's from DDT and its analogues before analysis with GLC. A small silica gel column was found to be suitable for removing two of the Aroclor series of PCB's (1254 and 1260) from DDT and its analogues.

  8. 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.

  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. 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.

  11. Phase polymorphism and electro-optical properties of a ferroelectric liquid crystal containing the biphenyl system

    NASA Astrophysics Data System (ADS)

    Zalewski, Sławomir; Ossowska-Chruściel, Mirosława D.

    2016-04-01

    In this article we present results concerning phase transitions and physical properties of the ferroelectric phase of the compound (S)-4-(1-methylheptyloxy)biphenyl-4'-(heptyloxy phenyl)-4-carboxylate (MHOBOPO7). The compound has the following phases: smectic ferroelectric C (SmC*), chiral nematic N*, and two defected phases, TGBC and blue phase. The mesomorphic properties were investigated by means of three complementary methods: differential scanning calorimetry, polarizing light optical microscopy, and transmitted light intensity. The electro-optical measurements were carried out on an ordered sample in a middle electric field during very slow cooling from the nematic phase to the ferroelectric phase.

  12. 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.

  13. Radiolytic dechlorination of polychlorinated biphenyls in transformer oil and in marine sediment

    NASA Astrophysics Data System (ADS)

    Chaychian, Mahnaz; Jones, Cynthia; Poster, Dianne; Silverman, Joseph; Neta, Pedatsur; Huie, Robert; Al-Sheikhly, Mohamad

    2002-11-01

    Radiolytic dechlorination of polychlorinated biphenyls (PCBs) in transformer oil and in marine sediments has been studied. At low PCB concentrations, complete degradation of the PCBs in transformer oil was achieved without degradation of the oil. Addition of an organic base, triethylamine, enhances the radiolytic dechlorination yield. The mechanism of dechlorination has been shown to involve electron transfer to PCBs from various aromatic radical anions formed in the irradiated oil. At high PCB concentrations, large amounts of triethylamine were necessary to achieve complete radiolytic dechlorination. Preliminary results on PCB-contaminated marine sediments demonstrate that addition of 2-propanol to the sediment/water slurry increases the effectiveness of the electron beam treatment.

  14. Isolation of bioactive biphenyl compounds from the twigs of Chaenomeles sinensis.

    PubMed

    Kim, Chung Sub; Subedi, Lalita; Kwon, Oh Kil; Kim, Sun Yeou; Yeo, Eui-Ju; Choi, Sang Un; Lee, Kang Ro

    2016-01-15

    Investigation of the MeOH extract of Chaenomeles sinensis twigs resulted in the isolation of seven biphenyl compounds (1-7) including a new compound, chaenomin (1). The chemical structures of the isolated compounds were elucidated by extensive NMR data ((1)H and (13)C NMR, (1)H-(1)H COSY, HSQC and HMBC), specific optical rotation, and chemical reaction. Compounds 2 and 6 showed potent cytotoxic activities against four cancer cell lines (A549, SK-OV-3, SK-MEL-2, and HCT15), and compound 7 exhibited potent anti-neuroinflammatory and NGF-potentiating activity. PMID:26706168

  15. An enthalpic basis of additivity in biphenyl hydroxamic acid ligands for stromelysin-1

    PubMed Central

    Wilfong, Erin M.; Du, Yu; Toone, Eric J.

    2013-01-01

    Fragment based drug discovery remains a successful tool for pharmaceutical lead discovery. Although based upon the principle of thermodynamic additivity, the underlying thermodynamic basis is poorly understood. A thermodynamic additivity analysis was performed using stromelysin-1 and a series of biphenyl hydroxamate ligands identified through fragment additivity. Our studies suggest that, in this instance, additivity arises from enthalpic effects, while interaction entropies are unfavorable; this thermodynamic behavior is masked by proton transfer. Evaluation of the changes in constant pressure heat capacities during binding suggest that solvent exclusion from the binding site does not account for the dramatic affinity enhancements observed. PMID:22985855

  16. 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

  17. Cloning and Characterization of Benzoate Catabolic Genes in the Gram-Positive Polychlorinated Biphenyl Degrader Rhodococcus sp. Strain RHA1

    PubMed Central

    Kitagawa, Wataru; Miyauchi, Keisuke; Masai, Eiji; Fukuda, Masao

    2001-01-01

    Benzoate catabolism is thought to play a key role in aerobic bacterial degradation of biphenyl and polychlorinated biphenyls (PCBs). Benzoate catabolic genes were cloned from a PCB degrader, Rhodococcus sp. strain RHA1, by using PCR amplification and temporal temperature gradient electrophoresis separation. A nucleotide sequence determination revealed that the deduced amino acid sequences encoded by the RHA1 benzoate catabolic genes, benABCDK, exhibit 33 to 65% identity with those of Acinetobacter sp. strain ADP1. The gene organization of the RHA1 benABCDK genes differs from that of ADP1. The RHA1 benABCDK region was localized on the chromosome, in contrast to the biphenyl catabolic genes, which are located on linear plasmids. Escherichia coli cells containing RHA1 benABCD transformed benzoate to catechol via 2-hydro-1,2-dihydroxybenzoate. They transformed neither 2- nor 4-chlorobenzoates but did transform 3-chlorobenzoate. The RHA1 benA gene was inactivated by insertion of a thiostrepton resistance gene. The resultant mutant strain, RBD169, neither grew on benzoate nor transformed benzoate, and it did not transform 3-chlorobenzoate. It did, however, exhibit diminished growth on biphenyl and growth repression in the presence of a high concentration of biphenyl (13 mM). These results indicate that the cloned benABCD genes could play an essential role not only in benzoate catabolism but also in biphenyl catabolism in RHA1. Six rhodococcal benzoate degraders were found to have homologs of RHA1 benABC. In contrast, two rhodococcal strains that cannot transform benzoate were found not to have RHA1 benABC homologs, suggesting that many Rhodococcus strains contain benzoate catabolic genes similar to RHA1 benABC. PMID:11673430

  18. 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.

  19. Cellular and molecular mechanisms mediating the effect of polychlorinated biphenyls on oocyte in vitro maturation.

    PubMed

    Pocar, Paola; Brevini, Tiziana A L; Antonini, Stefania; Gandolfi, Fulvio

    2006-08-01

    Cellular and molecular mechanisms mediating the effect of polychlorinated biphenyls on oocyte in vitro maturation: Polychlorinated biphenyls (PCBs) are stable, lipophilic compounds that accumulate in the environment and in the food chain. Recent studies provide evidence that exposure to PCBs can cause reproductive problems. PCBs have been identified in the ovarian follicle of women and other mammals and many data in the literature clearly indicate that both follicles and oocytes are particularly susceptible to these pollutants. In the present review we describe the multifaceted effects of PCBs on mammalian oocyte maturation in detail. Published studies clearly indicate that PCB congeners, both singly or as complex mixtures, disrupt mammalian oocyte maturation and subsequent embryo development. Specifically, data point out to the ability of PCBs to interfere with the organization of the microtubules cytoplasmic network resulting in an altered compartmentalization of the ooplasm. Furthermore, a critical role of cumulus cells in mediating PCB ovotoxicity has been observed, most likely related to a disregulation in intracellular communication between the germinal and the somatic compartment. Finally, since coplanar PCBs, induce gene expression via a ligand-dependent transactivating factor, the aryl hydrocarbon receptor, this signalling pathway is also reviewed with respect to understanding the toxic mechanisms of these compounds. PMID:16781112

  20. 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.

  1. 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.

  2. 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. PMID:26889751

  3. 3D QSAR studies of hydroxylated polychlorinated biphenyls as potential xenoestrogens.

    PubMed

    Ruiz, Patricia; Ingale, Kundan; Wheeler, John S; Mumtaz, Moiz

    2016-02-01

    Mono-hydroxylated polychlorinated biphenyls (OH-PCBs) are found in human biological samples and lack of data on their potential estrogenic activity has been a source of concern. We have extended our previous in silico 2D QSAR study through the application of advance techniques such as docking and 3D QSAR to gain insights into their estrogen receptor (ERα) binding. The results support our earlier findings that the hydroxyl group is the most important feature on the compounds; its position, orientation and surroundings in the structure are influential for the binding of OH-PCBs to ERα. This study has also revealed the following additional interactions that influence estrogenicity of these chemicals (a) the aromatic interactions of the biphenyl moieties with the receptor, (b) hydrogen bonding interactions of the p-hydroxyl group with key amino acids ARG394 and GLU353, (c) low or no electronegative substitution at para-positions of the p-hydroxyl group, (d) enhanced electrostatic interactions at the meta position on the B ring, and (e) co-planarity of the hydroxyl group on the A ring. In combination the 2D and 3D QSAR approaches have led us to the support conclusion that the hydroxyl group is the most important feature on the OH-PCB influencing the binding to estrogen receptors, and have enhanced our understanding of the mechanistic details of estrogenicity of this class of chemicals. Such in silico computational methods could serve as useful tools in risk assessment of chemicals. PMID:26598992

  4. Light-harvesting three-chromophore systems based on biphenyl-bridged periodic mesoporous organosilica.

    PubMed

    Grösch, Lyubov; Lee, Young Joo; Hoffmann, Frank; Fröba, Michael

    2015-01-01

    Three-chromophore systems with light-harvesting behavior were prepared, which are based on periodic mesoporous organosilica (PMO) with crystal-like ordered structure. The organic bridges of biphenyl-PMO in the pore walls act as donors and two types of dye are incorporated in the one-dimensional channels. Consecutive two-step-Förster resonance energy transfer is observed from the biphenyl moieties to mediators (diethyl-aminocoumarin or aminoacridone), followed by energy transfer from mediators to acceptors (dibenzothiacarbocyanine, indodicarbocyanine, sulforhodamine G). High energy-transfer efficiencies ranging from 70 to 80 % are obtained for two-step-FRET, indicating that the mesochannel structure with one-dimensional ordering provides spatial arrangement of chromophore pairs for an efficient direct energy transfer. The emission wavelength can be tuned by a choice of acceptor dye: 477 nm (diethylaminocoumarin), 519 nm (aminoacridone), 567 nm (sulforhodamine G), 630 nm (dibenzothiacarbocyanine), and 692 nm (indodicarbocyanine). PMID:25352478

  5. 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.

  6. Asymmetry between absorption and photoluminescence line shapes of TPD: spectroscopic fingerprint of the twisted biphenyl core.

    PubMed

    Scholz, Reinhard; Gisslén, Linus; Himcinschi, Cameliu; Vragović, Igor; Calzado, Eva M; Louis, Enrique; San Fabián Maroto, Emilio; Díaz-García, María A

    2009-01-01

    We analyze absorption, photoluminescence (PL), and resonant Raman spectra of N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine (TPD), with the aim of providing a microscopic interpretation of a significant Stokes shift of about 0.5 eV that makes this material suitable for stimulated emission. The optical spectra were measured for TPD dissolved in toluene and chloroform, as well as for polystyrene films doped with varying amounts of TPD. In addition, we measured preresonant and resonant Raman spectra, giving direct access to the vibrational modes elongated in the relaxed excited geometry of the molecule. The experimental data are interpreted with calculations of the molecular geometry in the electronic ground state and the optically excited state using density functional theory. Several strongly elongated high-frequency modes within the carbon rings results in a vibronic progression with a calculated spacing of 158 meV, corroborated by the observation of vibrational sidebands in the PL spectra. The peculiarities of the potential energy surfaces related to a twisting around the central bond in the biphenyl core of TPD allow to quantify the asymmetry between the line shapes observed in absorption and emission. PMID:19086796

  7. Effect of biphenyl ether herbicides on the formation of mutagenic intermediates from procarcinogens by rainbow trout

    SciTech Connect

    Miyauchi, M.; Uematsu, T.

    1987-08-01

    Increasing frequencies of tumors among aquatic animals in polluted waters have been reported. Experiments have also shown that exposure of fish to certain well-known and widely distributed xenobiotics causes them to develop tumors in a relatively short time. Formation of mutagenic intermediates from procarcinogens by fish liver homogenates had been reported. It is well established that fish have the ability to biotransform xenobiotics in a manner similar to that of mammalian species. These biotransformation include cytochrome P-450-dependent monooxygenase systems. In fish as well as mammals, cyt. P-450 systems are known to be induced by environmental pollutants. These inducers of cyt. P-450 systems are thought to influence the appearance of toxicity of chemicals. Biphenyl ether herbicides have been widely used all over the world, and particularly in Japan, they are indicated as environmental pollutants. Judging from their structures like as PCB, they are suspected to induce cyt. P-450 systems in fish. In this study, the effects of biphenyl ether herbicides and related compounds on the formation of mutagenic intermediates from procarcinogens by the S-9 fractions from rainbow trout were examined by using the Salmonella/microsome test.

  8. Experimental and theoretical studies on synthesis and structure elucidation of some polychlorinated biphenyl derivatives

    NASA Astrophysics Data System (ADS)

    Boyarskiy, Vadim P.; Boyarskaya, Irina А.; Savicheva, Elisaveta A.; Gdaniec, Maria; Fonari, Marina S.; Simonov, Yurii A.

    2010-06-01

    The regioselective methoxycarbonylation of polychlorinated biphenyls (PCBs), 2,3,4'-trichlorobiphenyl (РСВ22), and 2,5,4'-trichlorobiphenyl (PCB31), carried out in the presence of modified Co 2(CO) 8 cobalt carbonyl catalyst proceeds with substitution of chlorine atom in the position 3 for РСВ22 and yields methyl 2-chloro-3-(4-chlorophenyl)benzoate 1, while for PCB31 results in methyl 4-chloro-2-(4-chlorophenyl)benzoate 2. The substitution of methoxycarbonyl group for chlorine in ortho-position of trichlorobiphenyls seems not to affect the twist angle of the biphenyl unit. However, the twist angle of the methoxycarbonyl group relative to the phenyl ring was found to be significantly larger in the meta-derivative 1 than the ortho-derivative 2. To rationalize conformational differences between the two esters 1 and 2 in their crystal structures the optimized geometries and potential energy curves (relative energy versus torsion angle) were calculated at the B3LYP/6-31+G(d,p) level of theory.

  9. 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.

  10. Derivatization of bioactive carbazoles by the biphenyl-degrading bacterium Ralstonia sp. strain SBUG 290.

    PubMed

    Waldau, Doreen; Mikolasch, Annett; Lalk, Michael; Schauer, Frieder

    2009-05-01

    Different 9H-carbazole derivatives have been investigated within the last decades due to their broad range of pharmacological applications. While the metabolism of 9H-carbazole has previously been reported, nothing was known about the bacterial transformation of 2,3,4,9-tetrahydro-1H-carbazole and 9-methyl-9H-carbazole. Thus, for the first time, the bacterial biotransformation of 2,3,4,9-tetrahydro-1H-carbazole and 9-methyl-9H-carbazole was analyzed using biphenyl-grown cells of Ralstonia sp. strain SBUG 290 expressing biphenyl 2,3-dioxygenase. This strain accumulated 3-hydroxy-1,2,3,5,6,7,8,9-octahydrocarbazol-4-one and 6'-iminobicyclohexylidene-2',4'-dien-2-one as major products during the incubation with 2,3,4,9-tetrahydro-1H-carbazole. Carbazol-9-yl-methanol was verified as the primary oxidation product of 9-methyl-9H-carbazole. In addition, 9H-carbazol-1-ol, 9H-carbazol-3-ol, and 3-hydroxy-1,2,3,9-tetrahydrocarbazol-4-one where detected in lower concentrations during the transformation of carbazol-9-yl-methanol and 9-methyl-9H-carbazole. Products were identified by high-performance liquid chromatography, gas chromatography-mass spectrometry, liquid chromatography-mass spectrometry, as well as (1)H and (13)C nuclear magnetic resonance analyses. PMID:19148631

  11. The proton nuclear magnetic shielding tensors in biphenyl: experiment and theory.

    PubMed

    Schönborn, Frank; Schmitt, Heike; Zimmermann, Herbert; Haeberlen, Ulrich; Corminboeuf, Clémence; Grossmann, Gisbert; Heine, Thomas

    2005-07-01

    Line-narrowing multiple pulse techniques are applied to a spherical sample crystal of biphenyl. The 10 different proton shielding tensors in this compound are determined. The accuracy level for the tensor components is 0.3 ppm. The assignment of the measured tensors to the corresponding proton sites is given careful attention. Intermolecular shielding contributions are calculated by the induced magnetic point dipole model with empirical atom and bond susceptibilities (distant neighbours) and by a new quantum chemical method (near neighbours). Subtracting the intermolecular contributions from the (correctly assigned) measured shielding tensors leads to isolated-molecule shielding tensors for which there are symmetry relations. Compliance to these relations is the criterion for the correct assignment. The success of this program indicates that intermolecular proton shielding contributions can be calculated to better than 0.5 ppm. The isolated-molecule shielding tensors obtained from experiment and calculated intermolecular contributions are compared with isolated-molecule quantum chemical results. Expressed in the icosahedral tensor representation, the rms differences of the respective tensor components are below 0.5 ppm for all proton sites in biphenyl. In the isolated molecule, the least shielded direction of all protons is the perpendicular to the molecular plane. For the para proton, the intermediate principal direction is along the C-H bond. It is argued that these relations also hold for the protons in the isolated benzene molecule. PMID:15949748

  12. Continuous monitoring of polychlorinated biphenyls in air using direct sampling APCI/ITMS

    NASA Astrophysics Data System (ADS)

    Yamada, Masuyoshi; Suga, Masao; Waki, Izumi; Sakamoto, Masami; Morita, Masatoshi

    2005-06-01

    We report a continuous monitoring system of polychlorinated biphenyls (PCBs) in air, which uses direct sampling atmospheric pressure chemical ionization (APCI)/ion trap mass spectrometry (ITMS). In APCI, humidity in the atmosphere, which fluctuates from 0 to 10 vol.%, influences PCB sensitivity. In dry air (0.5% humidity), the detection limits of Di- to Hp-chlorinated biphenyls (CB) are 0.01-0.44 [mu]g/Nm3 ([mu]g/m3 at normal condition) with time resolution of 1 min, whereas the sensitivity decreases to less than 1/10 when water vapor concentration is 10 vol.%. The sensitivity decrease is calibrated in real-time using an internal standard, trichlorophenol. In order to obtain the calibration accuracy of +/-30%, we dilute the sample gas by dry air, decreasing the water vapor concentration below 1%. We applied the monitor to measure Di- to Hp-CB in ventilation air from a PCB decomposition plant. The monitored PCB concentration levels agreed well with that by high-resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS).

  13. Establishment of polychlorinated biphenyl-degrading enrichment culture with predominantly meta dechlorination

    SciTech Connect

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

    1992-09-01

    Enrichment of polychlorinated biphenyl (PCB)-dechlorinating microorganisms from PCB-contaminated sediments from the Upper Hudson River, N.Y., was attempted. The enrichment strategy was to use pyruvate as the electron donor and dechlorination of Aroclor 1242 as the electron acceptor. The enrichment medium also contained non-PCB-contaminated Hudson River sediments, which were required for the PCB-dechlorinating activity. An enrichment culture (that had stable PCBT-dechlorinating activity over nine serial transfers during 1 year) was established under these conditions; however, the rate of dechlorination did not increase after the second serial transfer. Dechlorination occurred primarily from the meta positions of the biphenyl molecule. Hydrogen could be substituted for pyruvate as the electron donor with equal activity, but when acetate was used as the electron donor a delay in dechlorination was observed. Sulfate and bromethane sulfonate inhibited dechlorination activity. The pyruvate-Aroclor 1242 enrichment also dechlorinated Aroclors 1248, 1254, and 1260; the extent of chlorine removed was the greatest for Aroclor 1254. For comparison, nonautoclaved non-PCB-contaminated Hudson River sediments used in the assay also dechlorinated Aroclors, but only after 12 to 16 weeks of incubation. This suggests that PCB-dechlorinating organisms were also present in these sediments but in numbers lower than those in the enrichment culture.

  14. Dechlorination of four commercial polychlorinated biphenyl mixtures (Aroclors) by anaerobic microorganisms from sediments

    SciTech Connect

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

    1990-08-01

    The rate, extent, and pattern of dechlorination of four Aroclors by inocula prepared from two polychlorinated biphenyl (PCB)-contaminated sediments were compared. The four mixtures used, Aroclors 1242, 1248, 1254, and 1260, average approximately three, four, five, and six chlorines, respectively, per biphenyl molecule. All four Aroclors were dechlorinated with the loss of meta plus para chlorines ranging from 15 to 85%. Microorganisms from an Aroclor 1242-contaminated site in the upper Hudson River dechlorinated Aroclor 1242 to a greater extent than did microorganisms from Aroclor 1260-contaminated sediments from Silver Lake, Mass. The Silver Lake inoculum dechlorinated Aroclor 1260 more rapidly than the Hudson River inoculum did and showed a preferential removal of meta chlorines. For each inoculum the rate and extent of dechlorination tended to decrease as the degree of chlorination of the Aroclor increased, especially for Aroclor 1260. The maximal observed dechlorination rates were 0.3, 0.3, and 0.2 {mu}g-atoms of Cl removed per g of sediment per week for Aroclors 1242, 1248, and 1254, respectively. The maximal observed dechlorination rates for Hudson River and Silver Lake organisms for Aroclor 1260 were 0.04 and 0.21 {mu}g-atoms of Cl removed per g of sediment per week, respectively. The dechlorination patterns obtained suggested that the Hudson River microorganisms were more capable than the Silver Lake organisms of removing the last para chlorine.

  15. [Gas chromatographic method for the analysis of polychlorinated biphenyls in pine needles].

    PubMed

    Zhu, X; Zhang, X; Yao, J; Liu, Z; Lu, P

    1999-07-01

    Polychlorinated biphenyls (PCBs) are a class of 209 chemical compounds, in which 1-10 chlorine atoms are attached to a biphenyl molecule. PCBs are members of halogenated aromatic group of environmental pollutants that have been identified worldwide in diverse environmental matrices. PCBs in air, soils, sediment, water, transformer oils and other environmental matrices have been determined in the past years. In this work a method for routine analysis of PCBs in pine needles has been developed. First, extractions were carried out in Soxhlet apparatus with n-hexane as solvent. Then, a silica gel chromatographic column was applied to pretreat the pine needle samples. The reference standard used was clophen 50. The recovery was about 90%, so the feasibility and reliability were assured. After the analysis of PCBs in pine needle samples from four different regions, the distribution of PCBs in environment can be discussed and monitored. In this method, a Shimadzu GC-7A gas chromatograph equipped with a 63Ni electron capture detector was used for the analysis of PCBs. From the results, we can see the PCB pollution in different regions. So evaluation of air pollution level through foliage data is feasible. The sample preparation and analytical method mentioned in this paper is reliable and simple. PMID:12552848

  16. Synthesis and pharmacological evaluation of new biphenylic derivatives as CB2 receptor ligands.

    PubMed

    Bertini, Simone; Chicca, Andrea; Arena, Chiara; Chicca, Stefano; Saccomanni, Giuseppe; Gertsch, Jürg; Manera, Clementina; Macchia, Marco

    2016-06-30

    Targeting type-2 cannabinoid receptor (CB2) is considered a feasible strategy to develop new drugs for the treatment of diseases like neuropathic pain, chronic inflammation, neurodegenerative disorders and cancer. Such drugs are devoid of the undesired central side effects that are typically mediated by the CB1 receptor. In this work we synthesized 18 biphenylic carboxamides as new CB2-selective ligands and evaluated their pharmacological profiles. The functional activity of these compounds is strongly influenced by the nature of the substituent at position 4' and 5 of the biphenyl scaffold. Position 5 seems to be responsible for the agonist or inverse agonist behaviour independently of the substituent in position 4', with the exception of the methoxyl group which transforms both full agonists and inverse agonists into neutral antagonists. This study provides a novel complete toolbox of CB2 functional modulators that derive from the same chemical scaffold. Such probes may be useful to investigate the biological role of CB2 receptors in cellular assays. PMID:27078864

  17. 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. PMID:25892208

  18. 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

  19. Conductance through single biphenyl molecules: symmetric and asymmetric coupling to electrodes.

    PubMed

    Kanthasamy, Karthiga; Pfnür, Herbert

    2015-01-01

    The contacts and the chemical bonds formed between metallic electrodes and molecules determine to a large extent the conductive properties of single molecular junctions, which represent the smallest possible active elements in an electronic circuit. We therefore investigated in a comparative study, using the break junction technique (MCBJ), the conductive properties of [1,1'-biphenyl]-4,4'-dithiol (M1) and of 4'-mercapto-[1,1'-biphenyl]-4-carbonitrile (M2) between gold electrodes. As a function of electrode separation, characterized by the conductance close to 0 V, we found several plateaus of relative stability, with those close to 0.01G0 being the most pronounced. The overall conductance of symmetric and asymmetric molecules were surprisingly similar, only the range of stability was smaller for M2. While M1 yielded symmetric I-V-curves, only small asymmetries were detected for M2. These are also reflected in the comparable values for coupling parameters using the single level resonance model. The high conductance for the asymmetric molecule is interpreted as a result of coherent coupling of electronic states through the whole molecule, so that the outcome cannot be predicted just by adding conductive properties of individual molecular groups. PMID:26425419

  20. 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.)

  1. 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.)

  2. 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.)

  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. 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-...

  6. 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…

  7. LAKE MICHIGAN FISH CONSUMPTION AS A SOURCE OF POLYCHLORINATED BIPHENYLS IN HUMAN CORD SERUM, MATERNAL SERUM, AND MILK

    EPA Science Inventory

    Reported consumption of Lake Michigan sport fish was examined in relation to the levels of polychlorinated biphenyls (PCBs) in biological samples provided by a sample of maternity patients. Fish consumption was correlated with PCB levels in maternal serum and milk but not in cord...

  8. DYNAMICS OF POLYCHLORINATED BIPHENYLS IN STRIPED BASS FROM THE HUDSON RIVER. 3. TISSUE DISPOSITION AND ROUTES FOR ELIMINATION

    EPA Science Inventory

    Striped bass were exposed to 14C-polychlorinated biphenyls (PCB) in single-dose and multiple-dose experiments. Samples were analyzed to determine rate constants for PCB elimination from individual tissues, PCB concentration in tissues, the proportion of the PCB burden retained an...

  9. 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...

  10. 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...

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  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...

  17. 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...

  18. 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...

  19. 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...

  20. 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...

  1. 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...

  2. 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...

  3. ASSESSMENT OF PCDDS (POLYCHLORINATED DIBENZODIOXINS) AND PCDFS (POLYCHLORINATED DIBENZOFURANS) FROM PCB (POLYCHLORINATED BIPHENYL'S) TRANSFORMER AND CAPACITOR FIRES

    EPA Science Inventory

    The EPA, under the Toxic Substances Control Act, has been mandated to develop appropriate regulations for the control of exposure to polychlorinated biphenyls (PCBs). In light of this responsibility the EPA Office of Toxic Substances recently issued an Advance Notice of Proposed ...

  4. POLYCHLORINATED BIPHENYLS AND OTHER ORGANIC CHEMICAL RESIDUES IN FISH FROM MAJOR UNITED STATES WATERSHEDS NEAR THE GREAT LAKES, 1978

    EPA Science Inventory

    Twenty-six composite samples of fish were collected during 1978 from United States watersheds near the Great Lakes and analyzed for polychlorinated biphenyls (PCBs) and related organic chemicals. PCB mixtures resembling Aroclor 1254 were found in all samples, and mixtures resembl...

  5. 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 ...

  6. 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...

  7. 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...

  8. Framework for Application of the Toxicity Equivalence Methodology for Polychlorinated Dioxins, Furans, and Biphenyls in Ecological Risk Assessment

    EPA Science Inventory

    Polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and biphenyls (PCBs) are commonly found as contaminants in complex mixtures in the environment. Several of these compounds bioaccumulate in the tissues of fish, birds, and mammals and have been shown to cause mo...

  9. 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 ...

  10. 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

    ... 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 ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION UNAVOIDABLE CONTAMINANTS IN FOOD FOR HUMAN...

  11. 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

    ... establishments manufacturing food-packaging materials. 509.15 Section 509.15 Food and Drugs FOOD AND DRUG... UNAVOIDABLE CONTAMINANTS IN ANIMAL FOOD AND FOOD-PACKAGING MATERIAL General Provisions § 509.15 Use of polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials. (a)...

  12. 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. PMID:26332829

  13. Biphenyl 4-Hydroxylases Involved in Aucuparin Biosynthesis in Rowan and Apple Are Cytochrome P450 736A Proteins.

    PubMed

    Sircar, Debabrata; Gaid, Mariam M; Chizzali, Cornelia; Reckwell, Dennis; Kaufholdt, David; Beuerle, Till; Broggini, Giovanni A L; Flachowsky, Henryk; Liu, Benye; Hänsch, Robert; Beerhues, Ludger

    2015-06-01

    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

  14. 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

  15. Structural insight into the expanded PCB-degrading abilities of a biphenyl dioxygenase obtained by directed evolution

    PubMed Central

    Kumar, Pravindra; Mohammadi, Mahmood; Viger, Jean-François; Barriault, Diane; Gomez-Gil, Leticia; Eltis, Lindsay D.; Bolin, Jeffrey T.; Sylvestre, Michel

    2011-01-01

    The biphenyl dioxygenase of Burkholderia xenovorans LB400 is a multicomponent Rieske-type oxygenase (RO) that catalyzes the dihydroxylation of biphenyl and many polychlorinated biphenyls (PCBs). The structural bases for the substrate specificity of the enzyme’s oxygenase component (BphAELB400) are largely unknown. BphAEp4, a variant previously obtained through directed evolution, transforms several chlorobiphenyls, including 2,6-dichlorobiphenyl, more efficiently than BphAELB400 yet differs from the parent oxygenase at only two positions: T335A/F336M. Herein, we compare the structure of BphAELB400 and BphAEp4 and examine the biochemical properties of two BphAELB400 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 did not contact biphenyl, but contributed significantly to expansion of the enzyme’s substrate range. Crystal structures indicate that Thr335 imposes constraints through hydrogen bonds and non-bonded 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, increasing the space available to accommodate the doubly-ortho-chlorinated congener 2,6-dichlorobiphenyl. This study provides important insight about how ROs can expand substrate range through mutations that increase the plasticity and/or mobility of protein segments lining the catalytic cavity. PMID:21073881

  16. Does the clam Ensis siliqua provide useful information about contamination by polychlorinated biphenyls and organochlorine pesticides beyond that of mussel Mytilus galloprovincialis?

    PubMed

    Ferrante, Maria Carmela; Clausi, Maria Teresa; Naccari, Clara; Fusco, Giovanna; Mattace Raso, Giuseppina; Santoro, Anna; Meli, Rosaria

    2014-06-01

    Several polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) investigated in soft tissues of the frequently monitored Mytilus galloprovincialis were compared to those of Ensis siliqua, a highly dispersed and economically important bivalve species, though rarely investigated. Overall PCBs had higher concentrations than OCPs in both species with a prevalence of tri- tetra-and penta-chlorinated biphenyls in E. siliqua and a prevalence of hexa- hepta and octa-chlorinated biphenyls in M. galloprovincialis. E. siliqua emerges as a suitable complement to mussels for monitoring PCBs and OCPs pollution. PMID:24667855

  17. Yucheng: health effects of prenatal exposure to polychlorinated biphenyls and dibenzofurans.

    PubMed

    Guo, Yueliang L; Lambert, George H; Hsu, Chen-Chin; Hsu, Mark M L

    2004-04-01

    Yucheng ("oil-disease") victims were Taiwanese people exposed to polychlorinated biphenyls (PCBs) and their heat-degradation products, mainly polychlorinated dibenzofurans (PCDFs), from the ingestion of contaminated rice oil in 1978-1979. Serial studies in Yucheng offspring born between 1978 and 1992 are summarized. Children of the exposed women were born with retarded growth, with dysmorphic physical findings, and, during development, with delayed cognitive development, increased otitis media, and more behavioral problems than unexposed children. Recently, examination of the reproductive system has suggested that prenatal exposure exerts late effects on semen parameters in young men after puberty. Results of the investigation in Yucheng children will provide important information about the human health effects and toxicology of PCB/PCDF exposure. Prenatal exposure to these environmental chemicals causes the fetus to be sensitive to the toxic effects of persistent organic pollutants. PMID:14963712

  18. Polychlorinated biphenyl (PCB) alters acid-sensitivity of cultured neurons derived from the medulla oblongata.

    PubMed

    Okada, Junichi; Shimokawa, Noriaki; Koibuchi, Noriyuki

    2005-07-01

    Polychlorinated biphenyls (PCBs) are known as environmental pollutants that may cause adverse health problems. However, little is known about the effects of PCBs on acid-sensitive neurons of the medulla oblongata, which regulate respiration. Therefore, the present study was designed to examine whether PCB alters acid-sensitivity of cultured neurons derived from the rat medulla oblongata. When extracellular pH was shifted from 7.4 to 7.0, acid-sensitive neurons showed depolarization, which was measured by voltage-sensitive fluorescent dye. Exposure to PCB (Aroclor 1254) decreased the amplitude of depolarization in low pH and increased the resting membrane potential in a dose-dependent manner. Taken together, our results indicate that PCB potentially influences acid-sensitivity through alteration of the membrane potential of acid-sensitive neurons, which could affect the regulation of respiration. PMID:15833269

  19. Hydroxylation of biphenyl by Aspergillus toxicarius: conditions for a bench scale fermentation process

    SciTech Connect

    Golbeck, J.H.; Cox, J.C.

    1984-01-01

    Fungi of the Aspergillus sp. can hydroxylate biphenyl to 4,4'-dihydroxybiphenyl, a chemical intermediate used in the plastics industry. The authors studied various batch culture conditions for the production of 4,4'-dihydroxybiphenyl, by Aspergillus toxicarius, in 25-mL shake flasks and 2-L fermenter cultures. Conditions investigated included temperature, aeration, carbon and nitrogen sources, biomass content, and time of substrate addition. Under optimum conditions the authors observed a rate of 4,4'-dihydroxybiphenyl production of 15-20 mg/day/g dry wt mycelia. Such a production rate is probably too low to support a commercial process and possible reasons for the low productivity are discussed.

  20. 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.

  1. Comparative effects of Aroclor 1254 (polychlorinated biphenyls) and phenanthrene on glucose uptake by freshwater microbial populations.

    PubMed Central

    Sayler, G S; Lund, L C; Shiaris, M P; Sherrill, T W; Perkins, R E

    1979-01-01

    The effects of polychlorinated biphenyl (PCB) and phenanthrene stress on glucose uptake by natural microbial populations were examined by the heterotrophic potential technique. Temporal and spatial distributions in glucose uptake velocities were examined for natural samples as well as PCB- and phenanthrene-stressed samples. Statistical analysis indicated significant variability among the various samples. It was demonstrated that the environmental variables contributed significantly to the variability in uptake kinetics. Although general trends indicated a PCB-induced stimulation in uptake velocities, these trends were in part masked by sample variability. Data analysis indicated no statistically significant PCB or phenanthrene effect on either total glucose uptake velocities or the proportion of 14CO2 evolved, as compared to natural unstressed samples. PMID:114110

  2. 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.

  3. The substituent effects on the biphenyl H⋯H bonding interactions subjected to torsion

    NASA Astrophysics Data System (ADS)

    Jiajun, Dong; Xu, Yuning; Xu, Tianlv; Momen, Roya; Kirk, Steven R.; Jenkins, Samantha

    2016-05-01

    QTAIM and the stress tensor describe a torsion φ, 0.0° ≤ φ < 25.0°, of the C4-C7 torsional bond that affects the H⋯H bonding interactions linking the two phenyl rings of para-substituted biphenyl, C12H9X, X = N(CH3)2, NH2, CH3, CHO, CN, NO2 and C12H9-Y, Y = SiH3, ZnCl, COOCH3, SO2NH2, SO2OH, COCl, CB3. For all values of X and Y, shorter H⋯H bond-path lengths corresponded to higher values of both the stiffness and torsion φ. The onset of a phase transition-like behavior is found by the stress tensor stiffness. The atomic basins of the H⋯H interactions are affected by the para-substituent groups.

  4. 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.

  5. Strain of alcaligenes latus bacteria used for the decomposition of polychlorinated biphenyls

    DOEpatents

    Dyadischev, Nikolai Romanovich; Zharikov, Gennady Alekseevich; Kapranov, Vladimir Vladimirovich

    2001-09-11

    Alcaligenes latus bacterial strain TXD-13 VKPM B 75-05 is capable of degrading polychlorinated biphenyls (PCBs). The strain may be employed to detoxicate environment media and PCB-containing industrial waste. To produce biomass, the strain is incubated on media which contain carbon sources, nitrogen sources and mineral salts. The strain is cultivated by a subsurface method up to a titer from 6.0.multidot.10.sup.8 to 2.0.times.10.sup.9 cells per cu cm. The produced biomass is used for degrading PCBs in concentrations from 10.sup.7 to 10.sup.8 cells per cu cm. The strain ensures from 35 to 50% reduction in PCB content in soil and water.

  6. [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. PMID:27430062

  7. Polychlorinated biphenyl congeners in emergent mayflies from the upper Mississippi River

    USGS Publications Warehouse

    Steingraeber, M.T.; Schwartz, T.R.; Wiener, J.G.; Lebo, J.A.

    1994-01-01

    We determined polychlorinated biphenyls (pcbs) in emergent mayflies (hexagenia bilineata) from a 1250-km reach of the upper mississippi river (umr). Total pcb concentrations (sum of 125 congeners) ranged from 0.21 To 4.1 Mu g/g of dry weight (1.2-29 mu g/g of lipid weight). Concentrations were highest in pools near the twin cities and the quad cities metropolitan areas. Longitudinal movement of pcbs was extensive downstream from the twin cities (175-320 km) but was not apparent downstream from the quad cities. The pcb composition of mayflies was relatively homogeneous throughout most of the river. However, the congener composition in mayflies from two distant locations differed markedly from the other samples and contained a greater abundance of lower molecular weight congeners. Recent pcb discharges from point and nonpoint sources may account for these differences. Emergent mayflies seem to be a useful indicator of pcb contamination of the umr.

  8. Polychlorinated dibenzo- p-dioxins, dibenzofurans, and biphenyls in soils of Moscow

    NASA Astrophysics Data System (ADS)

    Shelepchikov, A. A.; Brodskii, E. S.; Feshin, D. B.; Zhil'Nikov, V. G.; Mir-Kadyrova, E. Ya.; Balashova, S. P.

    2011-03-01

    The contents of polychlorinated dibenzo- p-dioxins (PCDDs), dibenzofurans (PCDFs), and biphenyls (PCBs) in the soils of Moscow were estimated. The concentrations of PCDDs and PCDFs mainly vary in the range of 0.27-16.1 ng WHO-TEQ/kg with single points of very high contamination up to 57.3 ng WHO-TEQ/kg; the concentrations of PCBs are in the range of 2.1-50.8 ng/g with sites of high contamination up to 4020 ng/g. The contribution of dioxin-like PCBs to the total dioxin toxic equivalent is very high: from 16 to 85%. The high levels of PCDDs and PCDFs in the soils indicate the strong contamination of the atmospheric air. The main source of these compounds is apparently motor transport.

  9. Pyrolysis gas chromatography-mass spectrometry of polychlorinated biphenyls on sediment

    SciTech Connect

    McMurtrey, K.D.; Wildman, N.J.; Tai, H.

    1983-12-01

    Polychlorinated biphenyls (PCBs) are common environmental contaminants which were freely employed for many years in numerous industrial applications but whose use has now been regulated. Many analytical schemes for monitoring these materials in environmental samples have been developed over the last decades, however, PCBs remain difficult analytical subjects. Most protocols rely on a combination of wet chemical pre-analytical isolation and purification whose complexity depends on the sample matrix. The time required for these manipulations may greatly hamper efforts directed towards emergency cleanup of accidental or illicit contamination of the environment. Thus, a clear need exists for methods which will allow rapid analysis of relatively intransigent samples for PCB contamination. Preliminary experiments directed to assessing the use of pyrolysis/gas chromatography/mass spectrometry in determining PCB contamination of soils and sediments are reported. In these experiments pyrolytic desorption at 1000/sup 0/C during 10 sec was used to completely replace more lengthy wet chemical manipulations.

  10. Depositional history of polychlorinated biphenyls in a dated sediment core from the northwestern Arabian Gulf.

    PubMed

    Gevao, Bondi; Aba, Abdul Aziz; Al-Ghadban, Abdul Nabi; Uddin, Saif

    2012-05-01

    The vertical distribution of polychlorinated biphenyls (PCBs) was measured in a dated sediment core from the northwestern Arabian Gulf to reconstruct their depositional history. The downcore profile showed an increase in concentrations from depth to a subsurface maximum of approximately 1,500 pg g(-1) in approximately 1991, followed by an exponential decrease to the sediment-water interface. Current concentrations of ΣPCBs are similar to levels predating the episodic input of PCBs in sediments dated coincident with the 1991 Arabian Gulf war. The spike in ΣPCB concentrations during the war may be related to the destruction of PCB-laden transformers during the conflict. The 15-fold decrease in ΣPCB concentrations from the period of maximum flux to prewar levels suggests that the factors delivering PCBs to sediments at present are similar to those that that existed before the war-related inputs. PMID:22218707

  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. Polychlorinated biphenyl levels in the Saginaw Confined Disposal Facility during disposal operations, Fall 1987. Final report

    SciTech Connect

    Myers, T.E.

    1991-01-01

    Pond water samples were collected from the Saginaw confined disposal facility (CDF), Saginaw, MI, during late summer and early fall 1987 and were analyzed for polychlorinated biphenyls (PCBs), suspended sediments and ammonia nitrogen. During this period, sediments from the Saginaw River was dredged and disposed in the Saginaw CDF. The perimeter dikes at the Saginaw CDF have a prepared limestone core that was designed to be permeable, Effluent monitoring is not practical because the discharge through permeable dikes is diffuse and is quickly diluted to background concentrations. This study, therefore, focused on collection of influent and pond water samples during disposal operations, and on the use of PCB concentrations in pond water samples to estimate the amount of PCB entering the dike and possibly being released from the CDF.

  13. 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.

  14. 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.

  15. Distribution pattern and reduction of polychlorinated biphenyls (PCB) in bluefish fillets through adipose tissue removal

    SciTech Connect

    Sanders, M.; Haynes, B.L.

    1988-11-01

    Bluefish, Pomatomus saltatrix, a migratory pelagic species of fish usually travel in large groups of like size along the Atlantic coast. Bluefish of all sizes are caught both commercially and recreationally for human consumption. Owing to its predacious nature, bluefish feed throughout the water column on a large variety of smaller fish and invertebrates. Bluefish bioaccumulate contaminants such as polychlorinated biphenyls (PCB) into various adipose tissues from the water column and through the marine food chain. Two recent reports concluded that PCB concentrations for all except some of the large bluefish caught along the Atlantic coast fell below the limit of 2 ..mu..g/g set by FDA. The purpose of this study was to observe the distribution pattern of PCB in the various edible tissues. Further, it was to determine if the removal of adipose tissues would result in reduced PCB level and therefore decrease PCB exposure to the consumer.

  16. 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

  17. 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.

  18. Polychlorinated biphenyl congeners in sediment cores from the Upper Mississippi River.

    PubMed

    Martinez, Andres; Schnoebelen, Douglas J; Hornbuckle, Keri C

    2016-02-01

    We determined polychlorinated biphenyls (PCBs) and radionuclide (137)Cs in sediment cores from the Upper Mississippi River (UMR) and the Iowa River, Iowa, at their confluence. Vertical distribution of (137)Cs indicated negligible mixing in the UMR core, while the Iowa River core showed signs of mixing. A clear (137)Cs 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 (137)Cs 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

  19. Transport of polychlorinated biphenyls (PCB) in the Scheldt Estuary simulated with the water quality model WASP

    NASA Astrophysics Data System (ADS)

    Vuksanovic, V.; De Smedt, F.; Van Meerbeeck, S.

    1996-01-01

    The main processes that govern the behaviour of the industrial compounds polychlorinated biphenyls (PCB) in the Scheldt Estuary are reviewed. It appears that tidal hydrodynamics, suspended sediment transport, and hydrophobic sorption regulate the distribution of PCB within the estuary. The water quality model WASP is applied to simulate the present spatial distribution of 12 selected PCB isomers. The simulations are performed under average hydrodynamic and suspended sediment transport regimes. Calculated evolution profiles of the dissolved and sorbed concentrations in the water column indicate a high accumulation of the PCB in the zone of the turbidity maximum. The simulated distributions of the sorbed PCB, suspended sediment and salinity in the water column agree with the observations, but more measurements are needed in order to verify the predictability of the simulations.

  20. Distribution characteristics of polychlorinated biphenyls (PCBs) in coastal areas of Okinawa Island, Japan

    NASA Astrophysics Data System (ADS)

    Sheikh, M. A.; Nakama, F.; Oomori, T.

    2007-07-01

    Surface sediment and seawater samples were collected from coastal areas around Okinawa Island from September 2001 to May 2002. The samples were analyzed for total polychlorinated biphenyl (PCB) levels and homolog composition. The results show that total PCB levels ranged from 0.32 to 128.7 ng/g (dry wt.) in sediment and 1.59 to 2.48 ng/L in seawater. The levels exceed the Environmental Quality Standard (EQS) for water pollution of Japan. The distribution of PCB homolog showed different patterns in the sediments and seawaters. Penta-chlorobiphenyls (CBs) comprised the main congener group in seawater, while hexa-CBs were more abundant homologs in the sediments. The heavily contaminated sites featured higher CBs, including penta-CBs, hexa-CBs, and hepta-CBs, than those in less contaminated sites where tri-CBs dominated. This study provides current distribution and geochemical behavior of PCBs in the coastal areas around Okinawa Island.

  1. Polychlorinated biphenyls in surface soil in urban and background areas of Mongolia.

    PubMed

    Mamontova, Elena A; Mamontov, Alexander A; Tarasova, Eugenia N; Kuzmin, Mikhail I; Ganchimeg, Darmaa; Khomutova, Marina Yu; Gombosuren, Odontuya; Ganjuurjav, Erdenebayasgalan

    2013-11-01

    Polychlorinated biphenyls (PCBs) were measured in soil in some industrial towns (Ulaanbaatar, Suhbaatar, Erdenet, Darhan, Tsetserleg, Hovd, Ulaangom, Altay, Bayanhongor, Arvayheer, Saynshand, Choybalsan) and in background and rural areas of Mongolia. The average sum of all investigated PCB congeners in soil of Mongolia comes to 7.4 ng/g dry weight (DW) and varies from 0.53 ng/g DW till 114 ng/g DW. PCB levels in soil from towns are significantly higher than those in soil from background and rural areas. The PCB homological composition in soil sampled in highly-PCB-polluted sites is similar to the PCB homological pattern in Sovol and Aroclor 1254. Significant correlation between soil organic carbon and low chlorinated PCB both for towns and background sites was found. Significant differences in PCB means in soil in different natural zones were found. PMID:23995023

  2. 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.

  3. Incubation stage and polychlorinated biphenyl (PCB) congener patterns in an altricial and precocial bird species.

    PubMed

    Custer, Christine M; Custer, Thomas W; Thyen, Stefan; Becker, Peter H

    2014-12-01

    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. PMID:25213805

  4. Distribution patterns of polychlorinated biphenyl congeners in water, sediment and biota from Midway Atoll

    SciTech Connect

    Titus, E.; Scatolini, S.; Cotter, J.; Hope, B.

    1995-12-31

    There are large gaps in the understanding of critical pathways of polychlorinated biphenyl (PCB) transfer from abiotic media into lower trophic level marine organisms and, subsequently to higher marine consumers, particularly for the North Pacific Ocean. In this study, twenty PCB congeners were quantified in surface water, sediment and tissues of marine biota taken from near-shore waters at Midway Atoll. PCB 138, 153, 180, and 187 were the most abundant congeners in all samples analyzed. Bioaccumulation was shifted in favor of higher chlorinated congeners in all species; only aquatic macrophytes displayed significant accumulation of lower chlorinated congeners. Non-ortho substituted congeners with toxic potency were below detection levels in the majority of species. Certain mono-ortho congeners, implicated in marine mammal toxicity, comprised only 4.5% of total congener load in potential forage species.

  5. Migration of CT triplet excitons in TCNB-biphenyl and TCNB-HMB crystals

    NASA Astrophysics Data System (ADS)

    Kozankiewicz, BolesAw

    1994-01-01

    Delayed fluorescence decay curves of charge transfer (CT) crystals of tetracyanobenzene with biphenyl (TCNB-B) and with hexamethylbenzene (TCNB-HMB) have been studied over a wide temperature range (5-200 K). The decay curves have been adequately described by decay expressions derived for different mechanisms of triplet-triplet annihilation. This analysis points to one-dimensional, thermally activated motion of CT triplet excitons. The estimated activation energies for the exciton hopping are 360±60 and 650±100 cm -1 (or 550±150 cm -1 depending on the applied model) for the TCNB-B and TCNB-HMB crystals, respectively. The results seem to confirm the self-trapping of triplet CT excitons.

  6. Chromatographic Retention Times of Polychlorinated Biphenyls: from Structural Information to Property Characterization

    PubMed Central

    Jäntschi, Lorentz; Bolboacă, Sorana D.; Diudea, Mircea V.

    2007-01-01

    The paper presents a unitary approach of the use of a Molecular Descriptors Family in structure-property/activity relationships, particularly in modelling the chromatographic retention times of polychlorinated biphenyls. Starting from molecular structure, viewed as a graph, and considering the bonds and bond types, atom types and often the 3D geometry of the molecule, a huge family of molecular descriptors called MDF was calculated. A preliminary selection of MDF members was done by simple linear regression (LR) against the measured property. The best fitted MDF subset is then submitted to multivariate linear regression (MLR) analysis in order to find the best pairs of MDF members that produce a reliable QSPR (Quantitative Structure-Property Relationship) model. The predictive capability was finally tested by randomly splitting of data into training and test sets. The best obtained models are presented and the results are discussed.

  7. Arbuscular Mycorrhizal Fungal Hyphae Alter Soil Bacterial Community and Enhance Polychlorinated Biphenyls Dissipation.

    PubMed

    Qin, Hua; Brookes, Philip C; Xu, Jianming

    2016-01-01

    We investigated the role of arbuscular mycorrhizal fungal (AMF) hyphae in alternation of soil microbial community and Aroclor 1242 dissipation. A two-compartment rhizobox system with double nylon meshes in the central was employed to exclude the influence of Cucurbita pepo L. root exudates on hyphal compartment soil. To assess the quantitative effect of AMF hyphae on soil microbial community, we separated the hyphal compartment soil into four horizontal layers from the central mesh to outer wall (e.g., L1-L4). Soil total PCBs dissipation rates ranged from 35.67% of L4 layer to 57.39% of L1 layer in AMF inoculated treatment, which were significant higher than the 17.31% of the control (P < 0.05). The dissipation rates of tri-, tetrachlorinated biphenyls as well as the total PCBs were significantly correlated with soil hyphal length (P < 0.01). Real-time quantitative PCR results indicated that the Rhodococcus-like bphC gene was 2-3 orders of magnitude more than that of Pseudomonas-like bphC gene, and was found responded positively to AMF. Phylogenetic analyses of the 16S rDNA sequenced by the Illumina Miseq sequencing platform indicated that AMF hyphae altered bacterial community compositions. The phylum Betaproteobacteria and Actinobacteria were dominated in the soil, while Burkholderiales and Actinomycetales were dominated at the order level. Taxa from the Comamonadaceae responded positively to AMF and trichlorinated biphenyl dissipation, while taxa from the Oxalobacteraceae and Streptomycetaceae responded negatively to AMF and PCB congener dissipation. Our results suggested that the AMF hyphal exudates as well as the hyphae per se did have quantitative effects on shaping soil microbial community, and could modify the PCBs dissipation processes consequently. PMID:27379068

  8. Hydroxylated polychlorinated biphenyl detection based on a genetically engineered bioluminescent whole-cell sensing system.

    PubMed

    Turner, Kendrick; Xu, Shifen; Pasini, Patrizia; Deo, Sapna; Bachas, Leonidas; Daunert, Sylvia

    2007-08-01

    The metabolites of polychlorinated biphenyls (PCBs), such as hydroxylated PCBs (OH-PCBs), have been identified as environmental contaminants. Various studies have shown that some OH-PCBs can potentially contribute to health problems. Detection of these compounds in environmental and biological samples could provide useful information about their levels and lead to a better understanding of their apparent toxicity. To that end, we have developed a whole-cell sensing system for the detection of OH-PCBs by taking advantage of the recognition of a group of related compounds, i.e., hydroxylated biphenyls, by the product of the hbpR gene in the hbp operon from Pseudomonas azelaica strain HBP1. By fusing the luxAB genes, encoding the reporter protein bacterial luciferase, to the hbp regulator-promoter sequence, a whole-cell sensing system was developed. Here, we describe the optimization and application of this whole-cell sensing system for the detection of a model compound, 2-hydroxy-3',4'-dichlorobiphenyl. A detection limit of 1 x 10(-8) M was achieved using this system. The detection of a broad range of individual OH-PCBs as well as an OH-PCB mixture was investigated. The system can detect OH-PCBs in whole serum samples in a trace amount, which is comparable to the detection of these analytes in medium alone. We envision that the method developed can potentially be employed as a rapid and sensitive way to monitor OH-PCBs for toxicological study in the laboratory, as well as a useful tool to evaluate the presence of bioavailable OH-PCBs in natural environments. PMID:17602671

  9. Blarina brevicauda as a biological monitor of polychlorinated biphenyls: Evaluation of hepatic cytochrome p450 induction

    USGS Publications Warehouse

    Russell, J.S.; Halbrook, R.S.; Woolf, A.; French, J.B., Jr.; Melancon, M.J.

    2004-01-01

    We assessed the value of short-tailed shrews (Blarina brevicauda) as a possible biomonitor for polychlorinated biphenyl pollution through measurement of the induction of hepatic cytochrome P450 and associated enzyme activities. First, we checked the inducibility of four monooxygenases (benzyloxyresorufin-O-dealkylase [BROD], ethoxyresorufin-O-dealkylase [EROD], methoxyresorufin-O-dealkylase [MROD], and pentoxyresorufin-O-dealkylase [PROD]) by measuring the activity of these enzymes in hepatic microsomes prepared from shrews injected with $-naphthoflavone ($NF) or phenobarbital (PB), typical inducers of cytochrome P4501A (CYP1A) and CYP2B enzyme families, respectively. Enzyme activity was induced in shrews that received $NF but not in shrews that received PB; PROD was not induced by either exposure. Later, shrews were exposed to a mixture of polychlorinated biphenyls (PCBs) (Aroclor 1242:1254, in 1:2 ratio) at 0.6, 9.6, and 150 ppm in food, for 31 d. Induction in these shrews was measured by specific enzyme activity (BROD, EROD, and MROD) in hepatic microsomes, by western blotting of solubilized microsomes against antibodies to CYP1A or CYP2B, and by duration of sodium pentobarbital-induced sleep. These three CYP enzymes were induced in shrews by PCBs at similar levels of exposure as in cotton rat (Sigmodon hispidus). Neither sleep time nor the amount of CYP2B family protein were affected by PCB exposure. Blarina brevicauda can be a useful biomonitor of PCBs that induce CYP1A, especially in habitats where they are the abundant small mammal.

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

    USGS Publications Warehouse

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

    1999-01-01

    Sediment cores of known chronology from Richardson and San Pablo Bays in San Francisco Bay, CA, were analyzed for a suite of chlorinated hydrocarbon pesticides and polychlorinated biphenyls to reconstruct a historic record of inputs. Total DDTs (DDT = 2,4'- and 4,4'-dichlorodiphenyltrichloroethane and the metabolites, 2,4'- and 4,4'-DDE, -DDD) range in concentration from 4-21 ng/g and constitute a major fraction (> 84%) of the total pesticides in the top 70 cm of Richardson Bay sediment. A subsurface maximum corresponds to a peak deposition date of 1969-1974. The first measurable DDT levels are found in sediment deposited in the late 1930's. The higher DDT inventory in the San Pablo relative to the Richardson Bay core probably reflects the greater proximity of San Pablo Bay to agricultural activities in the watershed of the Sacramento and San Joaquin rivers. Total polychlorinated biphenyls (PCBs) occur at comparable levels in the two Bays (< 1-34 ng/g). PCBs are first detected in sediment deposited during the 1930's in Richardson Bay, about a decade earlier than the onset of detectable levels of DDTs. PCB inventories in San Pablo Bay are about a factor of four higher in the last four decades than in Richardson Bay, suggesting a distribution of inputs not as strongly weighed towards the upper reaches of the estuary as DDTs. The shallower subsurface maximum in PCBs compared to DDT in the San Pablo Bay core is consistent with the imposition of drastic source control measures four these constituents in 1970 and 1977 respectively. The observed decline in DDT and PCB levels towards the surface of both cores is consistent with a dramatic drop in the input of these pollutants once the effect of sediment resuspension and mixing is taken into account.

  11. Arbuscular Mycorrhizal Fungal Hyphae Alter Soil Bacterial Community and Enhance Polychlorinated Biphenyls Dissipation

    PubMed Central

    Qin, Hua; Brookes, Philip C.; Xu, Jianming

    2016-01-01

    We investigated the role of arbuscular mycorrhizal fungal (AMF) hyphae in alternation of soil microbial community and Aroclor 1242 dissipation. A two-compartment rhizobox system with double nylon meshes in the central was employed to exclude the influence of Cucurbita pepo L. root exudates on hyphal compartment soil. To assess the quantitative effect of AMF hyphae on soil microbial community, we separated the hyphal compartment soil into four horizontal layers from the central mesh to outer wall (e.g., L1–L4). Soil total PCBs dissipation rates ranged from 35.67% of L4 layer to 57.39% of L1 layer in AMF inoculated treatment, which were significant higher than the 17.31% of the control (P < 0.05). The dissipation rates of tri-, tetrachlorinated biphenyls as well as the total PCBs were significantly correlated with soil hyphal length (P < 0.01). Real-time quantitative PCR results indicated that the Rhodococcus-like bphC gene was 2–3 orders of magnitude more than that of Pseudomonas-like bphC gene, and was found responded positively to AMF. Phylogenetic analyses of the 16S rDNA sequenced by the Illumina Miseq sequencing platform indicated that AMF hyphae altered bacterial community compositions. The phylum Betaproteobacteria and Actinobacteria were dominated in the soil, while Burkholderiales and Actinomycetales were dominated at the order level. Taxa from the Comamonadaceae responded positively to AMF and trichlorinated biphenyl dissipation, while taxa from the Oxalobacteraceae and Streptomycetaceae responded negatively to AMF and PCB congener dissipation. Our results suggested that the AMF hyphal exudates as well as the hyphae per se did have quantitative effects on shaping soil microbial community, and could modify the PCBs dissipation processes consequently. PMID:27379068

  12. Blarina brevicauda as a biological monitor of polychlorinated biphenyls: evaluation of hepatic cytochrome P450 induction.

    PubMed

    Russell, Julie S; Halbrook, Richard S; Woolf, Alan; French, John B; Melancon, Mark J

    2004-08-01

    We assessed the value of short-tailed shrews (Blarina brevicauda) as a possible biomonitor for polychlorinated biphenyl pollution through measurement of the induction of hepatic cytochrome P450 and associated enzyme activities. First, we checked the inducibility of four monooxygenases (benzyloxyresorufin-O-dealkylase [BROD], ethoxyresorufin-O-dealkylase [EROD], methoxyresorufin-O-dealkylase [MROD], and pentoxyresorufin-O-dealkylase [PROD]) by measuring the activity of these enzymes in hepatic microsomes prepared from shrews injected with beta-naphthoflavone (betaNF) or phenobarbital (PB), typical inducers of cytochrome P4501A (CYP1A) and CYP2B enzyme families, respectively. Enzyme activity was induced in shrews that received betaNF but not in shrews that received PB; PROD was not induced by either exposure. Later, shrews were exposed to a mixture of polychlorinated biphenyls (PCBs) (Aroclor 1242:1254, in 1:2 ratio) at 0.6, 9.6, and 150 ppm in food, for 31 d. Induction in these shrews was measured by specific enzyme activity (BROD, EROD, and MROD) in hepatic microsomes, by western blotting of solubilized microsomes against antibodies to CYP1A or CYP2B, and by duration of sodium pentobarbital-induced sleep. These three CYP enzymes were induced in shrews by PCBs at similar levels of exposure as in cotton rat (Sigmodon hispidus). Neither sleep time nor the amount of CYP2B family protein were affected by PCB exposure. Blarina brevicauda can be a useful biomonitor of PCBs that induce CYP1A, especially in habitats where they are the abundant small mammal. PMID:15352474

  13. Stimulatory effects of a microbially dechlorinated polychlorinated biphenyl (PCB) mixture on rat uterine contraction in vitro.

    PubMed

    Tsuneta, Taeko; Loch-Caruso, Rita; Quensen, John F; Boyd, Stephen A; Hanna, Mona; Grindatti, Carmen

    2008-06-01

    Microbially mediated reductive dechlorination has been advocated as the first part of a two-stage (anaerobic/aerobic) biotreatment process for polychlorinated biphenyls (PCBs) in sediments, and is generally viewed as a detoxication process. However, previous studies suggest that microbial dechlorination increases the ability to stimulate uterine contractions compared with the original PCB mixtures. Here, we investigate the composition and uterotonic activity of the commercial PCB mixture Aroclor 1260 before and after incubation with microorganisms eluted from PCB-contaminated sediment of the Hudson River. Incubation with microorganisms resulted in a partially dechlorinated mixture (HR1260) dominated by ortho-substituted PCBs with four or fewer chlorines per biphenyl. Aroclor 1260 that had not been incubated with microorganisms had no significant effect on contraction frequency of rat uterine strips (gestation day 10) in vitro, whereas HR1260 dramatically increased contraction frequency to 718+/-134% of the basal rate at a total PCB concentration of 70 microM (p<0.05). The microbial dechlorination increased 2,2',4,4'-tetrachlorobiphenyl and one or more of four congeners that co-eluted during chromatography (2,3,3',5-tetrachlorobiphenyl, 2,3',4,5-tetrachlorobiphenyl, 2,2',4,4',6-pentachlorobiphenyl and 2,2',4,5',6-pentachlorobiphenyl) to 24 and 8 mol%, respectively. However, the uterotonic activities of the latter congeners were modest when evaluated either solely or in a reconstituted mixture and could not fully account for the uterotonic activity of HR1260. Nonetheless, the relative abundance of congeners with three or fewer chlorines increased to 14 mol% as a group in HR1260, suggesting that these congeners collectively contribute to the uterotonic activity even though the abundance of any one congener in this group was less than 5 mol%. PMID:18359014

  14. Storage of serum in plastic and glass containers may alter the serum concentration of polychlorinated biphenyls.

    PubMed Central

    Karmaus, Wilfried; Riebow, John F

    2004-01-01

    Valid exposure assessment and biomonitoring of toxicants rely on standardized specimen collection, handling, storage, and measurement. In a study designed to determine organochlorine concentrations in blood samples, we recruited participants from registered anglers in Michigan. After participants were interviewed, blood was collected from study subjects, either at home by a phlebotomist or in a commercial blood-draw station. The phlebotomists stored their samples in glass containers, but without our knowledge, the commercial laboratory transferred the specimens to plastic containers for freezing in its central facility. Samples were analyzed in the Analytical Chemistry Section Laboratory of the Michigan Department of Community Health. This laboratory also provided information on storage in glass (n = 28) versus plastic containers (n = 113). We conducted linear regression analyses to assess factors that may explain the concentrations of polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (DDE), and polybrominated biphenyls (PBBs). Our results indicate that storage of serum in plastic containers altered the total concentrations of PCBs, in particular, the higher chlorinated PCBs (PCB-180 and PCB-199), but not DDE or PBBs. No other characteristics of the samples could explain the higher PCB values (0.75 micro g/L vs. 0.45 micro g/L; p = 0.025) of those stored in plastic containers. The proportion of PCB detects in both subsamples did not differ. Some preceding studies have provided information on whether specimens were stored in glass or plastic containers; however, a number of studies have not. We suggest the initiation of a new review process to determine whether these earlier reports were based on unbiased PCB determinations. We recommend standardizing specimen collection, handling, storage, and measurement, which is particularly necessary for newly emerging analytes. PMID:15121504

  15. 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.

  16. Polychlorinated Biphenyls, Glycaemia and Diabetes in a Population Living in a Highly Polychlorinated Biphenyls-Polluted Area in Northern Italy: a Cross-sectional and Cohort Study

    PubMed Central

    Zani, Claudia; Donato, Francesco; Magoni, Michele; Feretti, Donatella; Covolo, Loredana; Vassallo, Francesco; Speziani, Fabrizio; Scarcella, Carmelo; Bergonzi, Roberto; Apostoli, Pietro

    2013-01-01

    Conflicts of interests: the authors declare no potential conflict of interests. Background Polychlorinated biphenyls (PCBs) have been found to be associated with diabetes in some, but not all, studies performed so far. The aim of this study was to assess the association between PCB serum levels and glycaemia and diabetes in people living in Brescia, a highly industrialised PCB-polluted town in Northern Italy. Design and Methods 527 subjects were enrolled in a cross-sectional population-based study: they were interviewed face-to-face in 2003 and also provided a blood sample under fasting conditions. The concentration of 24 PCB congeners was determined using gas-chromatography (GC/MS). Subsequently, all subjects were included in a follow-up (cohort) study. According to the Local Health Authority health-care database, subjects were considered to be diabetic if they had diabetes at interview time (prevalent cases) or during a 7-year follow-up (incident cases). Results A total of 53 subjects (10.0%) were diabetics: 28 had diabetes at enrolment and other 25 developed the disease subsequently. Diabetes frequency increased according to the serum concentrations of total PCBs and single PCB congeners, but no association was found when estimates were adjusted for education, body mass index, age and gender by logistic regression analysis. Accordingly, glycaemia increased with PCB serum levels, but no association was observed when multiple regression analysis, including confounding factors, was performed. Conclusions This study does not support the hypothesis that PCB environmental exposure is strictly associated with diabetes or glycaemia. PMID:25170473

  17. Critical evaluation of polychlorinated biphenyl toxicity in terrestrial and marine mammals: increasing impact of non-ortho and mono-ortho coplanar polychlorinated biphenyls from land to ocean.

    PubMed

    Kannan, N; Tanabe, S; Ono, M; Tatsukawa, R

    1989-11-01

    Residues of potentially toxic non-ortho chlorine substituted coplanar 3,3',4,4'-tetra-,3,3',4,4',5-penta-, 3,3',4,4',5,5'-hexachlorobiphenyl and their mono- and di-ortho analogs 2,3',4,4',5-penta, 2,3,3',4,4'-penta-, 2,3,3',4,4',5-hexa- and 2,2',3,3',4,4'-hexa-, 2,2',3,4,4',5-hexachlorobiphenyl) were determined in humans, dogs, cats (terrestrial), a finless porpoise (Neophocoena phocoenoides--coastal), Dall's porpoises (Phocoenoides dalli, dalli), Baird's beaked whales (Berardius bairdii) and killer whales (Orcinus orca--open ocean). Among the coplanar polychlorinated biphenyl (PCB) congeners, the concentration of the di-ortho congeners was the highest and the non-ortho congeners was the lowest. However, all three coplanar PCBs occurred at significantly higher levels than toxic polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). The relative bioconcentration and metabolic capacity of terrestrial and marine mammals to these chemicals, suggest that the toxic threat of coplanar PCBs increases from land to ocean, but the reverse is true for PCDDs and PCDFs. The toxic threat of coplanar PCBs to higher aquatic predators such as cetaceans was principally assessed by 2,3,7,8-T4CDD Toxic Equivalent Analysis which is based on the induction of arylhydrocarbon hydroxylase (AHH) and ethoxyresorufin O-deethylase (EROD). Analysis indicates, in particular, that the bioaccumulation of toxic 3,3',4,4',5-penta- and 2,3,3',4,4'-pentachlorobiphenyls in carnivorous marine mammals is a cause for considerable concern. PMID:2515809

  18. Framework for Application of the Toxicity Equivalence Methodology for Polychlorinated Dioxins, Furans and Biphenyls in Ecological Risk Assessment (External Review Draft)

    EPA Science Inventory

    Polychlorinated dioxins (PCDDs), furans (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, where they have been demonstrated to cause mortality and adverse...

  19. PERINATAL EXPOSURE TO POLYCHLORINATED BIPHENYLS AROCLOR 1016 OR 1254 DID NOT ALTER BRAIN CATECHOLAMINES NOR DELAYED ALTERNATION PERFORMANCE IN LONG EVANS RATS

    EPA Science Inventory

    Several reports have indicated that polychlorinated biphenyls (PCB) altered development of biogenic amine systems in the brain, impaired behavioral performances and disrupted maturation of the thyroid axis. The current study examines whether these developmental effects of PCB ar...

  20. CHARACTERIZATION OF PCB (POLYCHLORINATED BIPHENYL) TRANSFORMER/CAPACITOR FLUIDS AND CORRELATION WITH PCDDS (POLYCHLORINATED DIBENZO-P-DIOXINS) AND PCDFS (POLYCHLORINATED DIBENZOFURANS) IN SOOT

    EPA Science Inventory

    Dielectric fluids in transformers and capacitors often contain polychlorinated biphenyls (PCBs) or chlorobenzenes. These substances may generate polychlorinated dibenzofurans (PCDFs) and polychlorinated dibenzo-p-dioxins (PCDDs) under certain conditions of combustion/pyrolysis. W...

  1. Polychlorinated Biphenyls (PCBs) and Polybrominated Diphenol Ethers (PBDEs) in Current and Historical Samples of Avian Eggs from Nesting Sites in Buzzards Bay, MA, USA

    EPA Science Inventory

    We measured concentrations of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in eggs from breeding colonies in Buzzards Bay, MA, USA. Eggs from two piscivorous bird species, common (Sterna hirundo) and roseate (Sterna dougallii) terns, were collected...

  2. Evaluation of Enhanced Comprehensive 2-D Gas Chromatography-Time-Of-Flight Mass Spectrometry for the Separation of Recalcitrant Polychlorinated Biphenyl Isomers

    EPA Science Inventory

    The separation of some recalcitrant polychlorinated biphenyl (PCB) isomers in extracts from environmental compartments has been a daunting task for environmental chemists. Summed quantitation values for coeluting PCB isomers are often reported. This composite data obscures the ac...

  3. Role of nitric oxide in the convulsive seizures induced by fluoroquinolones coadministered with 4-biphenyl acetic acid.

    PubMed

    Kohno, K; Niwa, M; Nozaki, M; Uematsu, T; Fujimura, H

    1997-11-01

    1. Contribution of nitric oxide to the convulsive seizures induced by fluoroquinolones (FQs) coadministered with 4-biphenyl acetic acid (BPAA), the active metabolite of fenbufen, was assessed in mice. 2. Enoxacin + 4-biphenyl acetic acid caused clonic seizures in all treated mice, followed by tonic seizures and death. These events were associated with a significant increase in intracerebellar cyclic GMP. 3. Pretreatment with the nitric oxide synthase (NOS) inhibitor, NG-nitro-L-arginine methylester (L-NAME), but not with D-NAME, significantly reduced the incidence of convulsions and lethality, as well as the increase in cyclic GMP. 4. Pretreatment with N-methyl-D-aspartic acid (NMDA)-receptor antagonist, MK-801, inhibited only the transition of clonic seizure to tonic seizure without affecting the incidence of clonic seizure and lethality. 5. These findings suggest that FQs + BPAA exert convulsions by activating NOS partly through the mediation of the NMDA receptor in the brain cells. PMID:9347323

  4. Use of mechanistic data in the IARC evaluations of the carcinogenicity of polychlorinated biphenyls and related compounds.

    PubMed

    Lauby-Secretan, Béatrice; Loomis, Dana; Baan, Robert; El Ghissassi, Fatiha; Bouvard, Véronique; Benbrahim-Tallaa, Lamia; Guha, Neela; Grosse, Yann; Straif, Kurt

    2016-02-01

    The IARC Monographs are a series of scientific reviews that identify environmental factors that can increase the risk of cancer in humans. In its first part, the principles and procedures of the IARC Monographs evaluations are summarized. In a second part, we present the most recent IARC evaluation of polychlorinated biphenyls (PCBs) and polybrominated biphenyls (PBBs), performed in February 2013: PCBs and dioxin-like PCBs were both classified into group 1 "carcinogens," while PBBs were evaluated as "probably carcinogenic to humans" (group 2A). Noteworthy is that the relative contributions of different PCB congeners to the carcinogenicity of PCB mixtures are not known. The use of mechanistic data for the classification into a higher category is discussed in the context of the history of the consecutive evaluations of several related polychlorinated compounds. PMID:26077316

  5. Early life-stage mortality in zebrafish (Danio rerio) following maternal exposure to polychlorinated biphenyls and estrogen

    SciTech Connect

    Westerlund, L.; Billsson, K.; Andersson, P.L.; Tysklind, M.; Olsson, P.E.

    2000-06-01

    In the present study, specific polychlorinated biphenyl (PCB) congeners were examined for embryo and early life stage mortality in zebrafish (Danio rerio). A set of eight PCBs and two hydroxylated PCBs and 17{beta}-estradiol were tested. Of the compounds tested, 4{prime}-OH-PCB30 (hydroxylated polychlorinated biphenyl) and PCB104 were found to be highly toxic to embryos following maternal exposure and transfer to the oocyte. It was also observed that 17{beta}-estradiol exposure resulted in a high incidence of embryo mortality. Analysis of estrogen receptor levels during embryonic development showed increased mRNA (ribonucleic acid) levels from the 1K stage to 50% epiboly. Following injection of the different compounds, the estrogen receptor mRNA levels were also analyzed in adult male fish to determine if there was a correlation between embryo mortality and estrogenicity of the studied PCBs. The two PCBs that were highly embryo toxic were observed to be estrogenic.

  6. Polychlorinated biphenyls in the freshwater environment. (Latest citations from the Selected Water Resources Abstracts database). Published Search

    SciTech Connect

    Not Available

    1994-01-01

    The bibliography contains citations concerning the occurrence and effects of polychlorinated biphenyls (PCBs) in the freshwater environment. Topics include sources, distribution, and accumulation rates for specific regions. The citations also discuss PCB bioaccumulation, pollutant pathways, introduction into the food chain, and results of long and short term monitoring of selected areas. Detection methods for PCB accumulation in fish and surficial sediments are also considered. (Contains 250 citations and includes a subject term index and title list.)

  7. Genetic and cell-free studies of PCB biodegradation in pseudomonas putida LB400. Book chapter. [PCB (polychlorinated biphenyls)

    SciTech Connect

    Mondello, F.J.; Bopp, L.H.

    1987-01-01

    An investigation into the ability of strains defective in biphenyl metabolism to degrade PCBs, strongly suggests that the same enzymes are used for both substrates. The genes encoding these enzymes have been isolated and are being characterized. The ability of cell-free extracts of P. putida LB400 to degrade PCBs has been examined. Results indicate that the enzymes for PCB metabolism are present in the soluble portion of the extract.

  8. Photoredox-Catalyzed Tandem Insertion/Cyclization Reactions of Difluoromethyl and 1,1-Difluoroalkyl Radicals with Biphenyl Isocyanides.

    PubMed

    Zhang, Zuxiao; Tang, Xiaojun; Dolbier, William R

    2015-09-18

    Using visible-light photoredox conditions, difluoromethylation and 1,1-difluoroalkylation of biphenyl isocyanides have allowed the synthesis of a series of 6-(difluoromethyl)- and 6-(1,1-difluoroalkyl)phenanthridines via tandem addition/cyclization/oxidation processes. The reactions are carried out in wet dioxane at room temperature using fac-Ir(ppy)3 as catalyst to form a large variety of substituted phenanthridine products in good to excellent yield. PMID:26336815

  9. Low-energy vibrational spectra of flexible diphenyl molecules: biphenyl, diphenylmethane, bibenzyl and 2-, 3- and 4-phenyltoluene.

    PubMed

    Martin-Drumel, M A; Pirali, O; Falvo, C; Parneix, P; Gamboa, A; Calvo, F; Bréchignac, Ph

    2014-10-28

    Gas phase absorption far-infrared (FIR) spectra of six flexible hydrocarbon molecules containing two phenyl groups -biphenyl, diphenylmethane, bibenzyl and 2-, 3-, 4-phenyltoluene- are reported for the first time, allowing an accurate determination of most of their active low-frequency vibrational modes. DFT calculations have been carried out at the harmonic and perturbative anharmonic levels to predict the vibrational spectra of these molecules and unambiguously assign observed vibrational modes. PMID:25208925

  10. Purification and characterization of the oxygenase component of biphenyl 2,3-dioxygenase from Pseudomonas sp. strain LB400.

    PubMed Central

    Haddock, J D; Gibson, D T

    1995-01-01

    The iron-sulfur protein of biphenyl 2,3-dioxygenase (ISPBPH) was purified from Pseudomonas sp. strain LB400. The protein is composed of a 1:1 ratio of a large (alpha) subunit with an estimated molecular weight of 53,300 and a small (beta) subunit with an estimated molecular weight of 27,300. The native molecular weight was 209,000, indicating that the protein adopts an alpha 3 beta 3 native conformation. Measurements of iron and acid-labile sulfide gave 2 mol of each per mol of alpha beta heterodimer. The absorbance spectrum showed peaks at 325 and 450 nm with a broad shoulder at 550 nm. The spectrum was bleached upon reduction of the protein with NADPH in the presence of catalytic amounts of ferredoxinBPH and ferredoxinBPH oxidoreductase. The electron paramagnetic resonance spectrum of the reduced protein showed three signals at gx = 1.74, gy = 1.92, and gz = 2.01. These properties are characteristic of proteins that contain a Rieske-type [2Fe-2S] center. Biphenyl was oxidized to cis-(2R,3S)-dihydroxy-1-phenylcyclohexa-4,6-diene by ISPBPH in the presence of ferredoxinBPH, ferredoxinBPH oxidoreductase, NADPH, and ferrous iron. Naphthalene was also oxidized to a cis-dihydrodiol, but only 3% was converted to product under the same conditions that gave 92% oxidation of biphenyl. Benzene, toluene, 2,5-dichlorotoluene, carbazole, and dibenzothiophene were not oxidized. ISPBPH is proposed to be the terminal oxygenase component of biphenyl 2,3-dioxygenase where substrate binding and oxidation occur via addition of molecular oxygen and two reducing equivalents. PMID:7592331

  11. Congener-specific polychlorinated biphenyl patterns in eggs of aquatic birds from the Lower Laguna Madre, Texas

    SciTech Connect

    Mora, M.A.

    1996-06-01

    Eggs from four aquatic bird species nesting in the Lower Laguna Madre, Texas, were collected to determine differences and similarities in the accumulation of congener-specific polychlorinated biphenyls (PCBs) and to evaluate PCB impacts on reproduction. Because of the different toxicities of PCB congeners, it is important to know which congeners contribute most to total PCBs. The predominant PCB congeners were 153, 138, 180, 110, 118, 187, and 92. Collectively, congeners 153, 138, and 180 accounted for 26 to 42% of total PCBs. Congener 153 was the most abundant in Caspian terns (Sterna caspia) and great blue herons (Ardea herodias) and congener 138 was the most abundant in snowy egrets (Egretta thula) and tricolored herons (Egretta tricolor). Principal component analysis indicated a predominance of higher chlorinated biphenyls in Caspian terns and great blue herons and lower chlorinated biphenyls in tricolored herons. Snowy egrets had a predominance of pentachlorobiphenyls. These results suggest that there are differences in PCB congener patterns in closely related species and that these differences are more likely associated with the species` diet rather than metabolism. Total PCBs were significantly greater (p < 0.05) in Caspian terns than in the other species. Overall, PCBs in eggs of birds from the Lower Laguna Madre were below concentrations known to affect bird reproduction.

  12. Serium levels of polychlorinated biphenyls and some organochlorine insecticides in women with recent and former missed abortions

    SciTech Connect

    Bercovici, B.; Wassermann, M.; Cucos, S.; Ron, M.; Wassermann, D.; Pines, A.

    1983-02-01

    Polychlorinated biphenyls and some organochlorine insecticides (DDT isomers and their metabolites, indane (..gamma..-BHC), dieldrin, heptachlor epoxide) were assessed in the serum of 17 women with recent missed abortions, 7 women who experienced one or several missed abortions in their past, and 7 women with normal, second trimester pregnancy. Fifty-three percent of the cases of recent missed abortion had PCB serum levels higher than the mean plus two standard deviations of the control group. The mean PCB serum level in women with recent missed abortion and relatively high PCB serum levels was significantly different from that of the control group (103.04 versus 20.69 ppb,P<0.001). The mean PCB serum level of the former missed abortions group was also significantly different from that of the control group (82.00 versus 20.69 ppb, P<0.001). The quantity of the higher chlorinated biphenyl homologues (penta- and hexachlorobiphenyls) was increased in the high PCB level, missed abortion group and in the former missed abortion group, while the lower chlorinated biphenyl homologues were decreased in these groups in comparsion with the control group. The fact that the former missed abortion group showed increased PCB serum levels similar to those found in the high PCB level, recent missed abortion group confirms the existence of an association between relatively high PCB serum levels and the occurance of missed abortion. (JMT)

  13. The effect of varying levels of sodium bicarbonate on polychlorinated biphenyl dechlorination in Hudson River sediment cultures.

    PubMed

    Yan, Tao; LaPara, Timothy M; Novak, Paige J

    2006-07-01

    The addition of different concentrations of sodium bicarbonate had a profound effect on 2,3,4,5-chlorobiphenyl (2,3,4,5-CB) dechlorination in Hudson River sediment cultures. The most extensive dechlorination was observed in cultures to which 100 mg l(-1) bicarbonate was added. Cultures amended with 1000 mg l(-1) bicarbonate had the least extensive dechlorination, with 2,4-CB and 2,5-CB as predominant end-products. A significant loss of total chlorinated biphenyl mass was observed in cultures to which < or = 500 mg l(-1) bicarbonate was added, suggesting that degradation beyond chlorinated biphenyls occurred. The dynamics of acetate formation were different among the treatments, with high acetate concentrations detected throughout the 303-day experiment in cultures to which 1000 mg l(-1) bicarbonate had been added. Sodium bicarbonate addition also had a significant impact on bacterial community structure as detected by polymerase chain reaction-denaturant gradient gel electrophoresis (PCR-DGGE) of 16S rRNA gene fragments. Three putative polychlorinated biphenyl (PCB) dechlorinators were identified; one Dehalococcoides-like population was detected in all enrichment cultures, whereas two Dehalobacter-like populations were only detected in the enrichment cultures with the most extensive dechlorination. These results suggest that the availability of bicarbonate, and potentially sodium, may affect PCB dechlorination in Hudson River sediment and thus need to be taken into consideration when assessing the fate of PCBs or implementing bioremediation. PMID:16817937

  14. Reductive Coupling of Diynes at Rhodium Gives Fluorescent Rhodacyclopentadienes or Phosphorescent Rhodium 2,2'-Biphenyl Complexes.

    PubMed

    Sieck, Carolin; Tay, Meng Guan; Thibault, Marie-Hélène; Edkins, Robert M; Costuas, Karine; Halet, Jean-François; Batsanov, Andrei S; Haehnel, Martin; Edkins, Katharina; Lorbach, Andreas; Steffen, Andreas; Marder, Todd B

    2016-07-18

    Reactions of [Rh(κ(2) -O,O-acac)(PMe3 )2 ] (acac=acetylacetonato) and α,ω-bis(arylbutadiynyl)alkanes afford two isomeric types of MC4 metallacycles with very different photophysical properties. As a result of a [2+2] reductive coupling at Rh, 2,5-bis(arylethynyl)rhodacyclopentadienes (A) are formed, which display intense fluorescence (Φ=0.07-0.54, τ=0.2-2.5 ns) despite the presence of the heavy metal atom. Rhodium biphenyl complexes (B), which show exceptionally long-lived (hundreds of μs) phosphorescence (Φ=0.01-0.33) at room temperature in solution, have been isolated as a second isomer originating from an unusual [4+2] cycloaddition reaction and a subsequent β-H-shift. We attribute the different photophysical properties of isomers A and B to a higher excited state density and a less stabilized T1 state in the biphenyl complexes B, allowing for more efficient intersystem crossing S1 →Tn and T1 →S0 . Control of the isomer distribution is achieved by modification of the bis- (diyne) linker length, providing a fundamentally new route to access photoactive metal biphenyl compounds. PMID:27355689

  15. Expression of Biphenyl Synthase Genes and Formation of Phytoalexin Compounds in Three Fire Blight-Infected Pyrus communis Cultivars.

    PubMed

    Chizzali, Cornelia; Swiddan, Asya K; Abdelaziz, Sahar; Gaid, Mariam; Richter, Klaus; Fischer, Thilo C; Liu, Benye; Beerhues, Ludger

    2016-01-01

    Pear (Pyrus communis) is an economically important fruit crop. Drops in yield and even losses of whole plantations are caused by diseases, most importantly fire blight which is triggered by the bacterial pathogen Erwinia amylovora. In response to the infection, biphenyls and dibenzofurans are formed as phytoalexins, biosynthesis of which is initiated by biphenyl synthase (BIS). Two PcBIS transcripts were cloned from fire blight-infected leaves and the encoded enzymes were characterized regarding substrate specificities and kinetic parameters. Expression of PcBIS1 and PcBIS2 was studied in three pear cultivars after inoculation with E. amylovora. Both PcBIS1 and PcBIS2 were expressed in 'Harrow Sweet', while only PcBIS2 transcripts were detected in 'Alexander Lucas' and 'Conference'. Expression of the PcBIS genes was observed in both leaves and the transition zone of the stem; however, biphenyls and dibenzofurans were only detected in stems. The maximum phytoalexin level (~110 μg/g dry weight) was observed in the transition zone of 'Harrow Sweet', whereas the concentrations were ten times lower in 'Conference' and not even detectable in 'Alexander Lucas'. In 'Harrow Sweet', the accumulation of the maximum phytoalexin level correlated with the halt of migration of the transition zone, whereby the residual part of the shoot survived. In contrast, the transition zones of 'Alexander Lucas' and 'Conference' advanced down to the rootstock, resulting in necrosis of the entire shoots. PMID:27410389

  16. Biphenyl compounds are hydroxyl radical scavengers: their effective inhibition for UV-induced mutation in Salmonella typhimurium TA102.

    PubMed

    Fujita, S; Taira, J

    1994-09-01

    In our previous study, we found several hydroxylated biphenyl compounds have a great scavenging effect for hydroxyl radicals (.OH). In this study, to elucidate the relationship between generation of the .OH and photo-mutagenesis, six biphenyl compounds such as dehydrodieugenol, dehydrodivanillyl alcohol, dehydrodidihydroeugenol, dehydrodicreosol, magnolol and honokiol, respectively, were examined for their ability to inhibit UV-induced mutation in Salmonella typhimurium TA102. The relative mutagenic activities (RMA, %) indicated the mutation frequency of treated cells divided by the mutation frequency of control cells times 100%. The RMA (%) are as follows: 28 +/- 1, 31 +/- 1, 33 +/- 1, 41 +/- 2, 62 +/- 1, and 62 +/- 4 at concentrations of 5 micrograms per plate for dehydrodieugenol, dehydrodivanillyl alcohol, dehydrodidihydroeugenol, dehydrodicreosol, magnolol, and honokiol, respectively. These values indicate that low concentrations of these biphenyl compounds effectively suppress UV-induced mutagenesis. Also, these compounds acted as effective antimutagens in a dose-dependent manner (0.00005-5 micrograms per plate). These compounds are effective .OH scavengers. Consequently, the results obtained above suggest that these compounds could inhibit against UV-induced mutations by scavenging of .OH generated by UV irradiation. The results also suggest that .OH are associated with UV-induced mutation in Salmonella typhimurium TA102. PMID:7982632

  17. Rapid detection of polychlorinated biphenyls at trace levels in real environmental samples by surface-enhanced Raman scattering.

    PubMed

    Zhou, Qin; Zhang, Xian; Huang, Yu; Li, Zhengcao; Zhang, Zhengjun

    2011-01-01

    Detection of trace levels of persistent pollutants in the environment is difficult but significant. Organic pollutant homologues, due to their similar physical and chemical properties, are even more difficult to distinguish, especially in trace amounts. We report here a simple method to detect polychlorinated biphenyls (PCBs) in soil and distilled spirit samples by the surface-enhanced Raman scattering technique using Ag nanorod arrays as substrates. By this method, polychlorinated biphenyls can be detected to a concentration of 5 μg/g in dry soil samples within 1 minute. Furthermore, based on simulation and understanding of the Raman characteristics of PCBs, we recognized homologues of tetrachlorobiphenyl by using the surface-enhance Raman scattering method even in trace amounts in acetone solutions, and their characteristic Raman peaks still can be distinguished at a concentration of 10(-6) mol/L. This study provides a fast, simple and sensitive method for the detection and recognition of organic pollutants such as polychlorinated biphenyls. PMID:22346675

  18. Changes in egg composition of American kestrels exposed to dietary polychlorinated biphenyls.

    PubMed

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

    2000-06-01

    Changes in the quality of eggs of birds exposed to polychlorinated biphenyls (PCBs) have been described, but have never been directly attributed to PCBs. Polychlorinated biphenyl residues in eggs have been associated with reduced reproductive success and embryonic deformities in wild birds. Egg size and composition, specifically the amount of albumen, yolk, and water in an egg, also influence the growth and viability of embryos and hatchlings, and consequently the reproductive success of birds. To deter mine whether PCB exposure of adult birds affected the size and composition of their eggs, 25 pairs of captive American kestrels (Falco sparverius) were fed a mixture of PCB-spiked (1248:1254:1260) food to give an approximate exposure of 7 mg/kg body weight/d, beginning 1 mo prior to pairing, and continuing throughout the courtship, egg-laying, and incubation periods. This dietary level in the adult female kestrels resulted in mean total PCB residues in the eggs of 34.1 microg/g wet weight (geometric mean), which is environmentally relevant. PCB residues in eggs increased with the time of female exposure to the contaminated diet and laying date. Variation in egg size within PCB clutches was significantly greater than within control clutches, although absolute egg mass and volume did not differ markedly by treatment. Only infertile eggs and only one egg per clutch were used for egg composition analysis. Yolks in the PCB-contaminated eggs were heavier, with less wet and dry albumen relative to control eggs. Water content and eggshell thickness were not significantly affected by PCB exposure. These results suggest that eggs from the PCB treatment have relatively more lipid and less protein available for embryonic development. Changes in egg composition were not associated with egg size, lay date, ambient temperature, humidity, or precipitation, which are factors known to affect these variables in bird eggs. The PCB-induced changes in egg composition described here

  19. Relationships of Polychlorinated Biphenyls and Dichlorodiphenyldichloroethylene (p,p’-DDE) with Testosterone Levels in Adolescent Males

    PubMed Central

    Gallo, Mia V.; Deane, Glenn D.; Nelder, Kyrie R.; DeCaprio, Anthony P.; Jacobs, Agnes

    2013-01-01

    Background: Concern persists over endocrine-disrupting effects of persistent organic pollutants (POPs) on human growth and sexual maturation. Potential effects of toxicant exposures on testosterone levels during puberty are not well characterized. Objectives: In this study we evaluated the relationship between toxicants [polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (p,p´-DDE), hexachlorobenzene (HCB), and lead] and testosterone levels among 127 Akwesasne Mohawk males 10 to < 17 years of age with documented toxicant exposures. Methods: Data were collected between February 1996 and January 2000. Fasting blood specimens were collected before breakfast by trained Akwesasne Mohawk staff. Multivariable regression models were used to estimates associations between toxicants and serum testosterone, adjusted for other toxicants, Tanner stage, and potential confounders. Results: The sum of 16 PCB congeners (Σ16PCBs) that were detected in ≥ 50% of the population was significantly and negatively associated with serum testosterone levels, such that a 10% change in exposure was associated with a 5.6% decrease in testosterone (95% CI: –10.8, –0.5%). Of the 16 congeners, the more persistent ones (Σ8PerPCBs) were related to testosterone, whereas the less persistent ones, possibly reflecting more recent exposure, were not. When PCB congeners were subgrouped, the association was significant for the sum of eight more persistent PCBs (5.7% decrease; 95% CI: –11, –0.4%), and stronger than the sum of six less persistent congeners (3.1% decrease; 95% CI: –7.2, 0.9%). p,p´-DDE was positively but not significantly associated with serum testosterone (5.2% increase with a 10% increase in exposure; 95% CI: –0.5, 10.9%). Neither lead nor HCB was significantly associated with testosterone levels. Conclusions: Exposure to PCBs, particularly the more highly persistent congeners, may negatively influence testosterone levels among adolescent males. The

  20. The selective dietary accumulation of planar polychlorinated biphenyls in the otter (Lutra lutra)

    SciTech Connect

    Leonards, P.E.G.; Zierikzee, Y.; Brinkman, U.A.T.; Cofino, W.P.; Straalen, N.M. van; Hattum, B. van

    1997-09-01

    The decline of the populations of otters in Western Europe is assumed to be related to the accumulation of polychlorinated biphenyls (PCBs) in this species. A study was conducted to investigate the trophic transfer of non-ortho, mono-ortho-, and di-ortho-substituted PCBs in the food web of the otter (Lutra lutra) in the Oude Venen lake system in the Netherlands, with relatively low PCB contamination. This area was one of the last strongholds of otters in the Netherlands and the species is considered to be virtually extinct since 1988. A marked increase in concentration of chlorinated biphenyls (CBs) was observed with successive trophic levels of the aquatic food web. Mean concentrations of the sum of 28 CB congeners ({Sigma}CB) increased from 142 ng CB/g (organic carbon basis) in sediment and particulate matter to 588 ng CB/g (lipid weight basis) in invertebrates, to 2,450 ng CB/g (lipid weight) in fish, and 70,940 ng CB/g (lipid weight) in otter. A diet-specific biomagnification factor (BMF) of 14 was calculated from fish to otter based on {Sigma}CB; however, on the basis of toxic equivalent concentrations ({Sigma}TEQ), a BMF of 41 was found. This higher BMF on TEQ basis was mainly due to the enrichment of non-ortho-substituted CB 126 in otter, compared to fish. In fish CB 126 contributed 30 to 50% to {Sigma}TEQ, while this congener contributed 60 to 80% in otters. A shift in the CB patterns was found from relatively high concentrations of lowly chlorinated CBs in the abiotic compartments to the higher chlorinated CBs (five to seven chlorine atoms) at the highest trophic level. The relatively low concentrations of CB 77 and CBs with vicinal H-atoms at the meta-para position in otter compared to fish indicates that otters can metabolize these CBs and have P4501A-like and P4502B- like enzyme systems. It appears that even in an ecosystem with relatively low CB contamination, concentrations of CBs can be relatively high in aquatic top predators.

  1. Isolation and characterisation of polychlorinated biphenyl (PCB) degrading fungi from a historically contaminated soil

    PubMed Central

    Tigini, Valeria; Prigione, Valeria; Di Toro, Sara; Fava, Fabio; Varese, Giovanna C

    2009-01-01

    Background Polychlorinated biphenyls (PCBs) are widespread toxic pollutants. Bioremediation might be an effective, cost competitive and environment-friendly solution for remediating environmental matrices contaminated by PCBs but it is still unsatisfactory, mostly for the limited biodegradation potential of bacteria involved in the processes. Very little is known about mitosporic fungi potential in PCB bioremediation and their occurrence in actual site historically contaminated soils. In the present study, we characterised the native mycoflora of an aged dump site soil contaminated by about 0.9 g kg-1 of Aroclor 1260 PCBs and its changing after aerobic biotreatment with a commercial complex source of bacteria and fungi. Fungi isolated from the soil resulting from 120 days of treatment were screened for their ability to adsorb or metabolise 3 target PCBs. Results The original contaminated soil contained low loads of few fungal species mostly belonging to the Scedosporium, Penicillium and Aspergillus genera. The fungal load and biodiversity generally decreased throughout the aerobic treatment. None of the 21 strains isolated from the treated soil were able to grow on biphenyl (200 mg L-1) or a mixture of 2-chlorobiphenyl, 4,4'-dichlorobiphenyl and 2,2',5,5'-tetrachlorobiphenyl (20 mg L-1 each) as sole carbon sources. However, 16 of them grew in a mineral medium containing the same PCBs mixture and glucose (10 g L-1). Five of the 6 isolates, which displayed the faster and more extensive growth under the latter conditions, were found to degrade the 3 PCBs apparently without the involvement of ligninolytic enzymes; they were identified as Penicillium chrysogenum, Scedosporium apiospermum, Penicillium digitatum and Fusarium solani. They are the first PCB degrading strains of such species reported so far in the literature. Conclusion The native mycoflora of the actual site aged heavily contaminated soil was mainly constituted by genera often reported as able to biodegrade

  2. Bioaccumulation profiles of polychlorinated biphenyl congeners and organochlorine pesticides in Ganges River dolphins

    SciTech Connect

    Senthilkumar, K.; Kannan, K.; Sinha, R.K.; Tanabe, S.; Giesy, J.P.

    1999-07-01

    Isomer-specific concentrations of polychlorinated biphenyls (PCBs) including non-, mono-, and di-ortho-substituted congeners, DDT and its metabolites, hexachlorocyclohexane (HCH) isomers, chlordane compounds, and hexachlorobenzene (HCB) were determined in river dolphin blubber and prey fishes collected during 1993 through 1996 from the River Ganges in India. Concentrations of organochlorines were also measured in the milk and liver of dolphins, benthic invertebrates, and sediments. The DDTs and PCBs were the predominant compounds found in dolphin tissues and fish that comprise the diet of dolphins. Concentrations of DDTs and PCBs in the blubber of dolphins were in the range of 30 to 120 and 1.5 to 25 {micro}g/g, lipid weight, respectively. Penta- and hexachlorobiphenyls collectively accounted for 68 to 80% of the total PCB concentrations in river dolphins. Hexachlorobiphenyl congener 138 (2.2{prime}, 3,4,4{prime},5{prime}-) was the most abundant in dolphin blubber and prey fishes. The isomer/congener pattern of PCBs and organchlorine pesticides suggested that there is less metabolism due to cytochrome P450 enzymes in Ganges river dolphins than in marine or terrestrial mammals. The mean 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQs) estimated in river dolphin blubber was greater than those that can cause adverse effects in mink. Comparison of organochlorine concentrations in river dolphins with those of the values reported for samples analyzed during 1988 through 1992 suggested that the contamination by these compounds has increased in the River Ganges.

  3. Enantiomeric composition of chiral polychlorinated biphenyl atropisomers in aquatic and riparian biota

    USGS Publications Warehouse

    Wong, C.S.; Garrison, A.W.; Smith, P.D.; Foreman, W.T.

    2001-01-01

    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. Nonracemic enantiomeric fractions (EFs) were observed for PCBs 91, 95, 136, and 149 for aquatic and riparian biota from Lake Hartwell, SC, a reservoir heavily contaminated with PCBs, and for these congeners and PCBs 132, 174, 176, and 183 in river fish and bivalves nationwide. Fish and bivalves showed marked differences in EFs as compared to sediment found at the same sampling sites, thus suggesting that PCBs are bioprocessed in biota in a different manner from those found in sediment (e.g., reductive dechlorination). Species-dependent patterns in PCB EFs were observed, which suggest differences in the ability of different species to bioprocess PCBs enantioselectively, most likely by metabolism. The presence of nonracemic PCBs in fish and bivalves suggests greater metabolic degradation of PCBs in these organisms than indicated from previous achiral studies and underscores the powerful potential of chiral analysis as a tracer of environmental bioprocesses.

  4. Evaluation of potential health effects associated with serum polychlorinated biphenyl levels.

    PubMed

    Stehr-Green, P A; Welty, E; Steele, G; Steinberg, K

    1986-12-01

    In late 1983, we conducted a cross-sectional epidemiologic study to evaluate persons at risk of exposure to three chemical waste sites by comparing clinical disease end points and clinical chemistry parameters with serum polychlorinated biphenyls (PCB) levels. A total of 106 individuals participated in the study. The only statistically significant finding in regard to self-reported, physician-diagnosed health problems was a dose-response relationship between serum PCB levels and the occurrence of high blood pressure; however, this association failed to achieve statistical significance (p = 0.08) when we controlled for possible confounding effects of both age and smoking. Serum triglyceride and cholesterol levels were also higher in the group with elevated serum PCBs; additionally, there were isolated statistically significant correlations of serum aspartate aminotransferase (SGOT) with serum lipid fraction-adjusted PCB level (r = -0.21) and serum albumin (r = -0.24) and total bilirubin (r = 0.30) with serum PCB level. Although the ranges of serum levels reported herein from exposures to PCBs in the general environment are lower than those that have been associated with acute symptoms or illness in other studies, whether these levels are associated with long-term health risks is not known. Associations of such chronic, low-dose exposures with observable health effects as suggested by this study must be evaluated further before any final conclusions can be drawn. PMID:3104024

  5. [Toxicity of polychlorinated biphenyls (PCB)--indoor air pollution by PCB-containing durable elastic sealants].

    PubMed

    Ludewig, S; Kruse, H; Wassermann, O

    1993-01-01

    The widespread use of the persistent and lipophilic polychlorinated biphenyls (PCB) e.g. in electrical engineering, hydraulics and chemistry of the polymers, caused their ubiquitous distribution and accumulation in food chains. Chronic toxicity in humans is known from several incidents of PCB contaminated food. Dose-response experiences, however, remain uncertain due to the technical grade of PCB as a complex mixture of about 150 congeners and many impurities, like polychlorinated dibenzodurans. Some information on the toxicity of a few PCB congeners is available from animal experiments. Large differences in enzyme-inductive efficacy between the PCB congeners rendered the use of toxicity equivalent factors (related to 2,3,7,8-TCDD, "Seveso-Dioxin") necessary. For risk assessment, the use of "sum of PCB", calculated from questionable determinations of 6 minor toxic congeners, is insufficient. Serious problems arise from evaporation of PCB e.g. in technical rooms of telephone companies (in Germany: Telekom) and generally, from sealing materials in buildings. The German Federal Health Administration, BGA, recommends 300 ng total PCB/m3 indoor air as "precautionary value". Since neither the extreme differences in toxicity of the congeners nor bioaccumulation are taken into account, this recommendation of BGA can not be justified any longer. PMID:8219584

  6. Contamination by polychlorinated biphenyls (PCBs) in striped dolphins (Stenella coeruleoalba) from the Southeastern Mediterranean Sea.

    PubMed

    Storelli, Maria Maddalena; Barone, Grazia; Giacominelli-Stuffler, Roberto; Marcotrigiano, Giuseppe Onofrio

    2012-09-01

    Concentrations of polychlorinated biphenyls (PCBs) including dioxin-like PCBs (non-ortho, PCB 77, PCB 126, and PCB 169 and mono-ortho, PCB 105, PCB 118, and PCB 156) were measured in different organs and tissues (melon, blubber, liver, kidney, lung, heart, and muscle tissue) of striped dolphins (Stenella coeruleoalba) from the Eastern Mediterranean Sea (Adriatic Sea). The mean highest levels were in blubber and melon, followed by liver, kidney, lung, heart, and muscle tissue. PCB profiles were similar in all tissues and organs being dominated by the higher chlorinated homologues (hexa-CBs, 55.8-62.1%; penta-CBs, 15.4-20.0%; and hepta-CB PCB 180, 12.7-16.5%). Major PCBs in all tissues were congeners 138 and 153 collectively accounting for 50.6-58.3% of the total PCB concentrations, followed by PCB 101, 105, 118, and 180 constituting from 27.0% to 31.0%. PCB levels were higher in adult males than in adult females. The estimated 2,3,7,8-TCDD toxic equivalents of non- and mono-ortho PCBs were much higher than the threshold level above which adverse effects have been observed in other marine mammals species, suggesting that striped dolphins in this region are at risk for toxic effects. PMID:21960363

  7. Temporal trends of hexabromocyclododecane, polybrominated diphenyl ethers and polychlorinated biphenyls in ringed seals from East greenland.

    PubMed

    Vorkamp, Katrin; Rigét, Frank F; Bossi, Rossana; Dietz, Rune

    2011-02-15

    Concentrations of hexabromocyclododecane (HBCD) were determined in a combination of archived and fresh blubber samples of juvenile ringed seals from East Greenland collected between 1986 and 2008. α-HBCD was the only diastereoisomer consistently above levels of quantification and showed a significant log-linear (exponential) increase from 2.0 to 8.7 ng/g lipid weight (median concentrations) with an annual rate of +6.1%. The concentrations were up to several orders of magnitude lower than those reported for marine mammals from industrialized areas. Previously presented time trends on polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) have been extended with new data for 2006 and 2008. ΣPBDE in juvenile seals was the only parameter with a slight upward trend, however, dependent on the low 1986 concentration. Removing this data point resulted in a downward trend, which also was found for adult seals with a time trend starting in 1994. ΣPCB decreased significantly in juvenile seals, again due to the 1986 value, while no trend was found for the adult animals. This indicates stagnating PCB concentrations at a relatively high level, in some cases possibly exceeding tolerable daily intake rates for seal blubber as traditional Arctic food items. PMID:21247098

  8. Relationships between polychlorinated biphenyls in molluscs, hydrological characteristics and human pressures, within Basque estuaries (northern Spain).

    PubMed

    Solaun, O; Rodríguez, J G; Borja, A; Larreta, J; Valencia, V

    2015-01-01

    Interannual variability of polychlorinated biphenyls (PCBs), measured in the soft tissues of Mytilus galloprovincialis mussels and Crassostrea gigas oysters, collected from estuarine waters within the Basque Country (Bay of Biscay), are investigated. Samples were collected in the autumn, between 2002 and 2011. Sites located within the ports of Bilbao and Pasaia showed the highest PCBs concentrations in molluscs; the lowest were observed in the mouth of the Oka estuary, an area of low population and industrial activity. Congener profiles of PCBs in the tissues of molluscs reveal the predominance of hexachlorobiphenyls (CB153 and CB138). In addition, redundancy analysis has shown that residence time, river flow and a 'pressure index' explain 57% of the variability in the PCB congener concentrations (the higher the values of these variables, the higher the concentration). Finally, Σ7PCB median concentrations in molluscs and sediments, collected from nearby sampling sites, were found to be moderately correlated (r(2)=0.513, p<0.01). PMID:25150824

  9. Toxicological assessment of polychlorinated biphenyls and their metabolites in the liver of Baikal seal (Pusa sibirica).

    PubMed

    Nomiyama, Kei; Hirakawa, Shusaku; Eguchi, Akifumi; Kanbara, Chika; Imaeda, Daisuke; Yoo, Jean; Kunisue, Tatsuya; Kim, Eun-Young; Iwata, Hisato; Tanabe, Shinsuke

    2014-11-18

    We have previously reported that high accumulation of dioxins and related compounds induced cytochrome P450 (CYP 1s) isozymes in the liver of wild Baikal seals, implying the enhanced hydroxylation of polychlorinated biphenyls (PCBs). The present study attempted to elucidate the residue concentrations and patterns of PCBs and hydroxylated PCBs (OH-PCBs) in the livers of Baikal seals. The hepatic residue concentrations were used to assess the potential effects of PCBs and OH-PCBs in combination with the analyses of serum thyroid hormones, hepatic mRNA levels, and biochemical markers. The hepatic expression levels of CYP1 genes were positively correlated with the concentration of each OH-PCB congener. This suggests chronic induction of these CYP1 isozymes by exposure to PCBs and hydroxylation of PCBs induced by CYP 1s. Hepatic mRNA expression monitoring using a custom microarray showed that chronic exposure to PCBs and their metabolites alters the gene expression levels related to oxidative stress, iron ion homeostasis, and inflammatory responses. In addition, the concentrations of OH-PCBs were negatively correlated with L-thyroxine (T4) levels and the ratios of 3,3',5-triiodo-L-thyronine (T3)/reverse 3,3',5'-triiodo-L-thyroninee (rT3). These observations imply that Baikal seals contaminated with high levels of OH-PCBs may undergo the disruption of mechanisms related to the formation (or metabolism) of T3 and T4 in the liver. PMID:25343573

  10. Spermatogenic capacity in fertile men with elevated exposure to polychlorinated biphenyls

    PubMed Central

    Petersen, MS; Halling, J; Weihe, P; Jensen, TK; Grandjean, P; Nielsen, F; Jørgensen, N

    2015-01-01

    Background Endocrine disrupting industrial chemicals, such as polychlorinated biphenyls (PCBs), are suspected to adversely affect male reproductive functions. Objectives The Faroe Islands community exhibits an unusually wide range of exposures to dietary contaminants, and in this setting we examined the possible association between PCB exposure and semen quality and reproductive hormones in fertile Faroese men. Methods Participants in this cross-sectional study include 266 proven fertile men residing in the Faroe Islands. PCB levels and hormone profiles were measured in serum samples taken at the clinical examination that included semen quality parameters. Results A significant positive association was seen between serum-PCB and the testosterone/estradiol ratio (p=0.04). In the unadjusted analyses, elevated PCB exposure was associated with increased serum concentrations of SHBG (p=0.01) and FSH (p=0.05). We found no association between the serum PCB concentration and the semen quality variables. Conclusion In this population of highly exposed fertile men, the current serum-PCB concentration was associated with higher androgen/estrogen ratio. Further studies are needed to establish the findings and further document PCB-associated hormonal effects, any time windows of increased susceptibility, and the role of PCB in sub-fecundity. PMID:25766940

  11. Occurrence of heavy metals (Hg, Cd, and Pb) and polychlorinated biphenyls in salted anchovies.

    PubMed

    Storelli, M M; Giachi, L; Giungato, D; Storelli, A

    2011-05-01

    The most popular brands of salted anchovies (Engraulis encrasicolus) from the Mediterranean Sea and Atlantic Ocean were purchased from several Italian supermarkets and grocery stores. Heavy metal (Hg, Cd, and Pb) and polychlorinated biphenyl (PCB) levels were determined and assessed by comparing the concentrations in these samples with the maximum permissible limits set by the European Union (Reg EC 629/2008 and Reg EC 1881/2006 [Off. J. Eur. Union L 173:3-9 and 364:5-24, respectively]). The Hg and Cd levels were higher than those of Pb in all samples examined. For Hg and Pb, the concentrations recorded in this study were below the authorized limits, while an appreciable percentage of samples from both locations (Mediterranean Sea, 35%, and Atlantic Ocean, 25%) showed Cd levels exceeding the threshold recommended for human consumption. Concerning PCBs, the results of principal component analysis showed that samples from the two different marine areas appeared to be discriminate, with Mediterranean anchovies more contaminated than the others, in spite of their lower lipid content. However, anchovy samples from both locations had dioxinlike-PCB levels (Mediterranean Sea, 0.011 pg World Health Organization toxic equivalency [WHO-TEQ] g(-1), wet weight, and Atlantic Ocean, 0.007 pg WHO-TEQ g(-1), wet weight) that were below the WHO-TEQ maximum concentration set by European regulation. The results of this study will help in generating data needed for the assessment of heavy metal and PCB intake from this food. PMID:21549051

  12. Polychlorinated biphenyl contamination of areas surrounding two transformer salvage companies, Colman, South Dakota, September 1977

    SciTech Connect

    Greichus, Y.A.; Dohman, B.A.

    1980-06-01

    Soil, corn plants, and foliage from areas surrounding two electrical salvage companies involved in reconditioning old transformers had unusually high levels of polychlorinated biphenyls. Levels decreased as distance from the factories increased. PCBs were dispersed into the air through incineration of waste oils; water and soil contamination was caused by runoff from the factories. PCBs found in the contaminated areas closely resembled Aroclor 1260 as did the PCBs in the waste oil, wherease PCBs in other areas were more similar to Aroclor 1254. PCBs on surface soils taken from an unplowed pasture near the factories also resembled Aroclor 1260, whereas samples taken from depths of 2 to 4 inches showed degradation of some PCB isomers. PCB concentrations in corn cobs and kernels were < 0.05 ppM, whereas leaves contained PCB levels of up to 2.2 ppM. PCB levels in earthworms and small rodents collected near the factories were considerably higher than levels in the same types of animals collected from other areas.

  13. Cellular biomarkers for measuring toxicity of xenobiotics: Effects of polychlorinated biphenyls on earthworm Lumbricus terrestris coelomocytes

    SciTech Connect

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

    1993-05-01

    Acute toxicity in earthworms (Lumbricus terrestris) was assayed immediately after 5-d filter paper exposure to the polychlorinated biphenyl (PCB) Aroclor 1254, using coelomocyte viability, total extruded cell counts (ECC), differential cell counts (DCC), and formation of erythrocyte (ER) and secretory rosettes (SR) with, and phagocytosis of, antigenic rabbit red blood cells (RRBC). Chronic toxicity was assayed using rates by which earthworms replaced viable immunoactive coelomocytes, removed noninvasively immediately after exposure, over an 18-week depuration period. All cytological parameters, except ECC, were acutely affected immediately after exposure, when tissue concentrations were ([anti X] [plus minus] SE) 91.2 [plus minus] 8.19 [mu]g PCB per gram dry mass. Replacement of viable immunoactive coelomocytes occurred within six weeks in unexposed control earthworms. Exposed earthworms showed significant alteration in viability, ECC, DCC, ER, and SR formation, and phagocytosis at 6 and 12 weeks when PCB tissue concentrations were 41 [plus minus] 0.31 and 30.2 [plus minus] 0.88 [mu]g/g dry mass, respectively. Replacement of extruded coelomocytes with normal DCC of viable immunocompetent cells was not observed until week 18, when PCB had decreased to 15.7 [plus minus] 0.83 [mu]g/g dry mass. Low inherent natural variability in coelomocyte viability, ECC, DCC, rosette formation, and phagocytosis, and their sensitivity to sublethal PCB body burdens, indicated that earthworm coelomocytes have potential as nonmammalian biomarkers for assaying acute and chronic sublethal toxicity of xenobiotics.

  14. Decrease in prosaposin in spermatozoon is associated with polychlorinated biphenyl exposure

    PubMed Central

    Cai, Jia-Li; Sun, Ling-Bin; Guo, Zhi-Zhun; Jiang, Xiao-Ming; Zheng, Guan-Chao; Qiu, Hui-Ling; Sha, Ai-Guo; Wang, Chong-Gang; Ren, Jian-Zhi; Zuo, Zheng-Hong

    2015-01-01

    Polychlorinated biphenyls (PCBs) are a class of ubiquitous persistent organic pollutants and they have been associated with declining male fertility. In the present study, we aimed to determine the responsiveness of prosaposin (Psap) expression to PCB exposure. Male C57 mice were exposed to PCB mixture (Aroclor 1254) of environmental related doses by oral gavage. After exposure for 50 days, the expression of Psap was significantly decreased by PCB exposure in epididymides and epydidymal spermatozoa, but not in testis. The Psap abundance in sperm was decreased in a dose-dependent manner. Benchmark dose modeling revealed the 95% lower confidence limit on the benchmark dose (BMDL) and Benchmark Dose (BMD) for Psap reduction were 1.25 and 8.89 μg/kg Aroclor 1254, and for sperm motility reduction were 11.85 and 61.9 μg/kg Aroclor 1254. The depressed Psap level also showed a significant correlation (P<0.01, r=-0.531) with PCB accumulation in liver. In men with detectable PCB exposure in semen, Psap expression in sperm was significantly decreased whereas the semen parameters were unaffected. Linear regression showed that a negative association between total PCB level in seminal plasma and Psap level in ejaculated spermatozoa (P<0.05, r=-0.396). In conclusion, our data suggested that the abundance of Psap in sperm sample may be a sensitive endpoint to predict PCB exposure. PMID:26045750

  15. Polychlorinated biphenyl residues and egg mortality in double-crested cormorants from the Great Lakes

    USGS Publications Warehouse

    Tillitt, D.E.; Ankley, G.T.; Giesy, J.P.; Ludwig, J.P.; Kurita-Matsuba, H.; Weseloh, D.V.; Ross, P.S.; Bishop, C.A.; Sileo, L.; Stromborg, K.L.; Larson, J.; Kubiak, T.J.

    1992-01-01

    We evaluated the overall potency of polychlorinated biphenyl (PCB)-containing extracts from double-crested cormorant (Phalacrocorax auritis) eggs with an in vitro bioassay system, the H4IIE rat hepatoma cell bioassay. Results from the H4IIE bioassay were strongly correlated with the hatching success of eggs in the colonies, whereas conventional methods of PCB analysis correlated poorly with hatching success of eggs from the same colonies. These observations suggest that even though concentrations of total PCB residues have declined in almost all compartments of the environment, their effects are still being observed. The significance of this observation is that the adverse symptoms presently observed in certain Great Lakes fish-eating waterbird populations do not appear to be caused by some as yet unidentified industrial chemical or chemicals and seem not to be the result of pesticides, but rather to the dioxin-like activity of PCBs. Evidence is presented to suggest that the relative enrichment of the potency of PCBs in the environment may play a role in the persistence of the observed adverse symptoms.

  16. Chicago air quality: PCB (polychlorinated biphenyl) air-monitoring plan. Phase 2. Final report

    SciTech Connect

    Not Available

    1986-04-01

    Polychlorinated biphenyls (PCBs) have significant commercial value because of their high chemical and physical stability, resistance to fire, low vapor pressure, and high dielectric (insulating) strength. The chemical stability and physical properties of PCBs that have made them commercially valuable also makes their safe disposal difficult. The environmentally preferred option for disposing of PCB containing wastes is incineration. In order to provide assurance that the operation of the SCA incinerator did not represent a threat to public health, the Illinois EPA initiated an air-sampling study in the vicinity to measure the levels of PCBs in the ambient air. Quality control checks conducted during the study revealed a previously unknown weakness in the analysis method that caused the quantitative results to be unreliable. A revised method has now been validated and will be used to further characterize ambient air quality and assess the environmental impact, if any, of the incineration of PCBs in Chicago. The document presents the overall plan for the project. Objectives: (1) Quantitatively determine PCB levels in the ambient air at three locations in the area of impacted by the SCA incinerator in southeast Chicago; (2) Correlate the air sampling results and meteorological conditions with the operational parameters from the SCA incinerator; (3) Assess the environmental impact associated with the incineration of PCBs; (4) Establish background concentrations of PCBs in the ambient air in the area.

  17. Evidence for novel mechanisms of polychlorinated biphenyl metabolism in Alcaligenes eutrophus H850

    SciTech Connect

    Bedard, D.L.; Haberl, M.L.; May, R.J.; Brennan, M.J.

    1987-05-01

    Previous studies indicated that Alcaligenes eutrophus H850 attacks a different spectrum of polychlorinated biphenyl (PCB) congeners than do most PCB-degrading bacteria and that novel mechanisms of PCB degradation might be involved. To delineate this, the authors have investigated the differences in congener selectivity and metabolite production between H850 and Corynebacterium sp. strain MB1, an organism that apparently degrades PCBs via a 2,3-dioxygenase. H850 exhibited a superior ability to degrade congeners via attack on 2-, 2,4-, 2,5-, or 2,4,5-chlorophenyl rings in PCBs but an inferior ability to degrade congeners via attack on a 4-chlorophenyl ring. Reactivity preferences were also reflected in the products formed from unsymmetrical PCBs; thus, MB1 attacked the 2,3-chlorophenyl ring of 2,3,2',5'-tetrachlorobiphenyl to yield 2,5-dichlorobenzoic acid, while H850 attacked the 2,5-chlorophenyl ring to yield 2,3-dichlorobenzoic acid and a novel metabolite, 2',3'-dichloroacetophenone. Furthermore, H850 oxidized 2,4,5,2',4',5'-hexachlorobiphenyl, a congener with no adjacent unsubstituted carbons, to 2',4',5'-trichloroacetophenone. The atypical congener selectivity pattern and novel metabolites produced suggest that A. eutrophus H850 may degrade certain PCB congeners by a new route beginning with attack by some enzyme other than the usual 2,3-dioxygenase.

  18. Toxicological effects of polychlorinated biphenyls (PCBs) on freshwater turtles in the United States.

    PubMed

    Ming-Ch'eng Adams, Clare Isabel; Baker, Joel E; Kjellerup, Birthe V

    2016-07-01

    Prediction of vertebrate health effects originating from persistent organic pollutants (POPs) such as polychlorinated biphenyls (PCBs) has remained a challenge for decades thus making the identification of bioindicators difficult. POPs are predominantly present in soil and sediment, where they adhere to particles due to their hydrophobic characteristics. Animals inhabiting soil and sediment can be exposed to PCBs via dermal exposure while others may obtain PCBs through contaminated trophic interaction. Freshwater turtles can serve as bioindicators due to their strong site fidelity, longevity and varied diet. Previous research observed the health effects of PCBs on turtles such as decreased bone mass, changed sexual development and decreased immune responses through studying both contaminated sites along with laboratory experimentation. Higher deformity rates in juveniles, increased mortality and slower growth have also been observed. Toxicological effects of PCBs vary between species of freshwater turtles and depend on the concertation and configuration of PCB congeners. Evaluation of ecotoxicological effects of PCBs in non-endangered turtles could provide important knowledge about the health effects of endangered turtle species thus inform the design of remediation strategies. In this review, the PCB presence in freshwater turtle habitats and the ecotoxicological effects were investigated with the aim of utilizing the health status to identify areas of focus for freshwater turtle conservation. PMID:27043381

  19. Polychlorinated biphenyl congener distributions in burbot: evidence for a latitude effect.

    PubMed

    Stapanian, Martin A; Madenjian, Charles P; Cott, Peter A; Rediske, Richard R; O'Keefe, James P

    2014-11-01

    The authors compared the distributions of the congeners of polychlorinated biphenyls (PCBs) detected in whole-body samples of burbot (Lota lota) from Great Slave Lake and Lake Erie. Total PCB concentrations in Great Slave Lake burbot were about one-sixtieth of the concentrations in Lake Erie burbot. Burbot from Great Slave Lake contained a higher proportion of lower-chlorinated (2-6 chlorines) congeners than did burbot from Lake Erie; the reverse occurred for more highly chlorinated (7-9 chlorines) congeners. Hexachloro congeners, followed by pentachloro congeners, dominated the proportions of total PCBs in burbot from both lakes. There were no differences between sexes in whole-body samples or between gonad and somatic tissues in the proportions of the 39 congeners and 3 sets of coeluters detected in burbot from Great Slave Lake. In contrast, there were distinct sex differences in congener distributions for older burbot from Lake Erie. The results generally supported a prediction of higher proportions of lower-chlorinated PCB homologs in organisms in remote polar areas. However, the latitudinal effect on PCB congener distribution may be more complex than that portrayed in previous studies. PMID:25088677

  20. Organochlorines including polychlorinated biphenyls in muscle, liver, and ovaries of cod, Gadus morhua

    SciTech Connect

    Hellou, J.; Warren, W.G.; Payne, J.F. )

    1993-11-01

    Twenty-three specific organochlorine contaminants and polychlorinated biphenyls (PCBs), measured as three Aroclor standards were analyzed in muscle, liver, and ovaries of cod, Gadus morhua, collected in the Northwest Atlantic. In general, contaminants were undetectable in muscle tissue, while concentrations were 10 times lower in ovaries than liver (wet weight). Comparison of results to other locations indicated a similarity between the ratio of the concentrations of p,p'-DDE, p,p'-DDD and p,p'-DDT, in liver of cod from the northern North Sea and from the Northwest Atlantic, although with lower levels in the present study. The ratio of alpha-HCH and gamma-HCH was between that of the central and northern North Sea. Similar ratios tend to indicate similar residence times in the atmosphere, from source to sampling area. Comparison of sigma PCB and sigma DDT in the liver of cod from various geographical locations showed the following general trend in concentrations: Arctic, Northwest Atlantic, West Atlantic, Norway < North Baltic, Nova Scotia, North Sea < South Baltic. It was observed that if the liver concentration of one compound was low (high), there was a tendency for all compounds to be low (high). Cluster analysis of organochlorines in liver pointed to the presence of four basic clusters, which could reflect similar physical chemical properties within a group. Concentrations of organochlorines in ovaries were below levels expected to affect egg and larval viability.

  1. Accumulation Features of Polychlorinated Biphenyls and Organochlorine Pesticides in Resident and Migratory Birds from South India

    PubMed

    Tanabe; Senthilkumar; Kannan; Subramanian

    1998-05-01

    Persistent organochlorines such as DDT and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), chlordane compounds (CHLs), hexachlorobenzene (HCB), and polychlorinated biphenyls (PCBs) were determined in whole-body homogenates of resident and migratory birds collected from South India. Organochlorine contamination pattern in birds varied depending on their migratory behaviour. Resident birds contained relatively greater concentrations of HCHs (14-8,800 ng/g wet wt) than DDTs and PCBs concentrations. In contrast, migrants exhibited elevated concentrations of PCBs (20-4,400 ng/g wet wt). The sex differences in concentrations and burdens of organochlorines in birds were pronounced, with females containing lower levels than males. Inland piscivores and scavengers accumulated greater concentrations of HCHs and DDTs while coastal piscivores contained comparable or greater amounts of PCBs. Global comparison of organochlorine concentrations indicated that resident birds in India had the highest residues of HCHs and moderate to high residues of DDTs. It is, therefore, proposed that migratory birds wintering in India acquire considerable amounts of HCHs and DDTs. Estimates of hazards associated with organochlorine levels in resident and migratory birds in India suggested that Pond Heron, Little Ringed Plover, and Terek Sandpiper may be at risk from exposure to DDTs. PMID:9543510

  2. Analytical services Organization Union Valley sample Preparation facility Polychlorinated Biphenyl (PCB) Annual Inventory Document

    SciTech Connect

    Brown, B.J.

    1998-06-01

    The Analytical Services Organization (ASO), Union Valley Sample Preparation Facility (UVSPF), provides analytical testing in support of the Department of Energy (DOE), Oak Ridge Operations (ORO), and associated sites. Samples generated on the Oak Ridge Reservation (ORR) are routinely received at the WSPF for analytical evaluatiotiidentification. Many of these samples are polychlorinated biphenyl (PCB) regulated from a source or being sent to the facility to determine PCB content. PCB laboratory wastes in solid and liquid form are generated during the evaluation of these materials, requiring the WSPF staff to maintain formal storage areas for staging the materials prior to off-site shipment for disposal. The purpose of this report is to fulfill the requirements set forth in Title 40, Code of Federal Regulations (CFR), Part 761.180(a), Subpart J, which requires owners or operators of a facility using or storing PCBS to prepare an annual inventory document by July 1 of the current year which covers the previous calendar year. This report provides documentation of the inventory of PCB materials/wastes that were generated, stored for dispos~ and shipped off site for disposal for the period January 1, 1997, to January 1, 1998. The following is a summary of materials/wastes subject to the aforementioned reporting requirements.

  3. Plant compounds that induce polychlorinated biphenyl biodegradation by Arthrobacter sp. strain B1B.

    PubMed Central

    Gilbert, E S; Crowley, D E

    1997-01-01

    Plant compounds that induced Arthrobacter sp. strain B1B to cometabolize polychlorinated biphenyls (PCBs) were identified by a screening assay based on the formation of a 4,4'-dichlorobiphenyl ring fission product. A chemical component of spearmint (Mentha spicata), l-carvone, induced Arthrobacter sp. strain B1B to cometabolize Aroclor 1242, resulting in significant degradation of 26 peaks in the mixture, including selected tetra- and pentachlorobiphenyls. Evidence for PCB biodegradation included peak disappearance, formation of a phenylhexdienoate ring fission product, and chlorobenzoate accumulation in the culture supernatant. Carvone was not utilized as a growth substrate and was toxic at concentrations of greater than 500 mg liter-1. Several compounds structurally related to l-carvone, including limonene, p-cymene, and isoprene, also induced cometabolism of PCBs by Arthrobacter sp. strain B1B. A structure-activity analysis showed that chemicals with an unsaturated p-menthane structural motif promoted the strongest cometabolism activity. These data suggest that certain plant-derived terpenoids may be useful for promoting enhanced rates of PCB biodegradation by soil bacteria. PMID:9143124

  4. A biphenyl type two-photon fluorescence probe for monitoring the mitochondrial membrane potential.

    PubMed

    Moritomo, Hiroki; Yamada, Kengo; Kojima, Yuki; Suzuki, Yasutaka; Tani, Seiji; Kinoshita, Hazuki; Sasaki, Akira; Mikuni, Shintaro; Kinjo, Masataka; Kawamata, Jun

    2014-01-01

    Here we describe the design and synthesis of a bifunctional two-photon fluorescence probe, N,N'-‍dimethyl-4,4'-(biphenyl-2,1-ethenediyl)dipyridinium hexafluorophosphate (BP6). HeLa, Hek293, and Paramecium caudatum cells were stained with BP6. BP6 accumulated on the mitochondria of all three cell types when the mitochondrial membrane potential was high. As the mitochondrial membrane potential decreased following the addition of carbonyl cyanide m-chlorophenyl hydrazine, BP6 moved from the mitochondria to the nucleus in a reversible manner, depending on the mitochondrial membrane potential status. The maximum value of the two-photon absorption cross-section of BP6 is 250 GM (1 GM=1×10(-50) cm(4) s molecules(-1) photon(-1)). This value is 3 and 30 times larger, respectively, than that of the conventional mitochondria selective probes, rhodamine 123 and green fluorescence protein. These results suggest that BP6 should be useful for monitoring mitochondrial membrane potential by two-photon excitation. PMID:25319070

  5. Characteristic accumulation and soil penetration of polychlorinated biphenyls and polybrominated diphenyl ethers in wastewater irrigated farmlands.

    PubMed

    Wang, Thanh; Wang, Yawei; Fu, Jianjie; Wang, Pu; Li, Yingming; Zhang, Qinghua; Jiang, Guibin

    2010-11-01

    The impact of wastewater irrigation on the distribution of two groups of persistent organic pollutants (POPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), in farm soil was investigated in this study. The concentrations of total analyzed PCBs were in the range 256-2140pgg(-1) on dry weight basis in surface soils. There was a higher accumulation of PCBs in farms irrigated by wastewater, with decachlorobiphenyl (CB-209) as the predominant congener. The spatial distributions of PBDEs were similar although not as obvious as that of PCBs, and BDE-209 was the predominant congener at 2040-496000pgg(-1)dw, accounting for >96% of the total analyzed PBDEs. However, no significant correlations could be found between PCB and PBDE concentrations in the topsoil samples, and also with soil organic content between the different sites. On the other hand, soil vertical profiles showed significant relationship with soil organic content in cores taken from farms irrigated with wastewater. The vertical distribution was quite uniform at the topsoil, corresponding to the plowed layer, and decreased thereafter exponentially. Furthermore, the soil vertical distribution was found to be congener specific for PCBs, where less chlorinated congeners were able to penetrate deeper into the soil while heavier congeners were more restricted in their movement. This fractionation process was however not found for PBDEs. Also, the prevalence and high relative concentrations of CB-11 and CB-209 suggests that these PCB congeners should more often be included in routine environmental analysis in order to identifying unusual contamination sources. PMID:20846706

  6. A toxic equivalency factor scale for polychlorinated biphenyls (PCBs) in chicken hepatocytes

    SciTech Connect

    Tysklind, M.; Bosveld, A.T.C.; Sinnige, T.; Berg, M. van den

    1995-12-31

    The relative potencies of 20 polychlorinated biphenyls (PCBs) were studied in a chicken embryo hepatocyte system. The 20 congeners were selected according to a full 2{sup 4}-factorial design based on the principal properties of all 154 tetra- through heptachlorinated PCBs. The principal properties were obtained using principal component analysis (PCA) on a multitude of different physico-chemical properties of the PCBs. Toxic equivalency factors (TEFs) were determined for seven out of the twenty PCB congeners, viz. PCB{number_sign}41, PCB{number_sign}60, PCB{number_sign}78, PCB{number_sign}126, PCB{number_sign}169, PCB{number_sign}190, and PCB{number_sign}193, which elicit measurable catalytic ethoxyresorufin-O-deethylase (EROD) activity in the chicken hepatocytes. A multivariate quantitative structure-activity relationship (QSAR) was developed by using partial least-squares to latent variables (PLS) in order to model the relationship between the set of physico-chemical descriptors of the PCBs and their TEF-values. The model showed good correlations between observed and predicted TEF-values for this training set of congeners. From the QSAR, TEF-values were predicted for a large number PCB congeners not yet tested regarding EROD activity in chicken hepatocytes. The predicted TEF-values were validated by TEF-values reported in the literature.

  7. Impaired host resistance to endotoxin and malaria in polychlorinated biphenyl- and hexachlorobenzene-treated mice.

    PubMed Central

    Loose, L D; Silkworth, J B; Pittman, K A; Benitz, K F; Mueller, W

    1978-01-01

    The in vivo effect of polychlorinated biphenyl (PCB) and hexachlorobenzene (HCB) on murine endotoxin sensitivity and resistance to malaria (Plasmodium berghei NYU-2) infection was studied. The dietary administration of 167 ppm (167 microgram/g) of PCB 1242 or HCB for 3 weeks resulted in an enhanced sensitivity to gram-negative endotoxin (Salmonella typhosa), which was further increased in animals maintained on the diets for 6 weeks. By 6 weeks, a 5.2- or 32-fold increase in endotoxin sensitivity was seen in mice fed PCB or HCB, respectively. A 20% decrease in mean survival time of mice fed PCB 1242 for 3 or 6 weeks and inoculated with malaria was demonstrated. Infected mice that received HCB for 3 or 6 weeks manifested a reduction in mean survival time of 24 or 31%, respectively. Histopathological examination revealed a normal thymus, spleen, mesenteric lymph nodes, and lungs. Centrilobular and pericentral hepatocyte hypertrophy, common to organochlorine exposure, was observed. Electron capture gas chromatographic analysis for PCB 1242 or HCB in the tissues examined histologically revealed a significant deposit of the xenobiotics. HCB concentration was approximately 16 to 25 times greater than that of PCB. The data indicate that environmental chemicals impair host resistance and that the alteration may be related to the presence of the chemicals in the lymphoreticular organs. PMID:97225

  8. Polychlorinated biphenyl exposure and effects in tree swallows (Tachycineta bicolor) residing at eight locations

    USGS Publications Warehouse

    Yorks, A.L.; Rattner, B.A.; Melancon, M.J.

    1998-01-01

    Twelve-day-old Tree Swallow nestlings were studied at eight sites exhibiting a range of polychlorinated biphenyl (PCB) contamination. In addition to determining PCB concentrations in eggs, nestlings, and food items, hepatic cytochromes P450-associated monooxygenase activity quantified as a biomarker of exposure. Nestlings from several of the sites exhibited elevated PCB concentrations and P450 induction compared to a reference site, Furthermore, cytochromes P450 were correlated with PCB concentrations in nestling. Our findings indicate that likely routes of exposure include the direct materna! deposition of PCBs into the egg and the delivery of contaminated emerging aquatic insects to nestlings. We also examined reproductive and morphological parameters to determine if PCB exposure was adversely affecting swallows at these sites. Hatching success did not differ among sites. There were no dramatic effects on gross and histological gonadal morphology of nestlings, and there was complete concordance between phenotypic sex (gonadal morphology) and genotypic sex (as determined by PCR amplification of the sex chromosome). However, where nestling PCB exposure was substantial, clutch size and body weight differed from a reference site. Despite evidence of PCB exposure, only modest effects were observed in nestling swallows.

  9. Oculodermatological findings in workers with occupational exposure to polychlorinated biphenyls (PCBs).

    PubMed Central

    Fischbein, A; Rizzo, J N; Solomon, S J; Wolff, M S

    1985-01-01

    Oculodermatological findings, such as hypersecretion of the Meibomian glands, swelling of the upper eyelids and hyperpigmentation of the conjunctivae are considered typical of "PCB poisoning." They were common clinical manifestations of yusho and yu-cheng, two epidemics in Japan and Taiwan caused by the ingestion of rice cooking oil contaminated with polychlorinated biphenyls (PCBs) and polychlorinated dibenzofurans. To investigate the prevalence of such abnormalities in a population with long term occupational exposure to PCBs, a group of 326 workers employed in two capacitor manufacturing facilities were investigated in 1976, and 195 of these again in 1979. The median blood values of lower homologues of PCBs were 63 ppb (in plasma) in 1976 and 49 ppb (in serum) in 1979, and of the higher homologues 18 ppb and 17 X 5 ppb respectively. The prevalence of oculodermatological findings potentially related to the effects of PCBs were 9 X 4% and 13 X 3% at the two examinations. There was no significant association between such abnormalities and blood plasma/serum concentrations of PCBs. The observations in this work population exposed to PCBs differ from the yusho and yu-cheng experiences in that fewer clinical abnormalities were found. Suggestions are made that it may be inappropriate to extrapolate findings from the well known PCB poisoning episodes to exposures in occupational settings and that attention should be paid to the importance of polychlorinated dibenzofurans as an aetiological factor in human PCB poisoning. PMID:3924093

  10. Polychlorinated biphenyls in coastal tropical ecosystems: Distribution, fate and risk assessment

    SciTech Connect

    Dodoo, D.K.; Essumang, D.K.; Jonathan, J.W.A.; Bentum, J.K.

    2012-10-15

    Polychlorinated biphenyls (PCBs) though banned still find use in most developing countries including Ghana. PCB congener residues in sediments in the coastal regions of Ghana were determined. Sediment samples (n=80) were collected between June 2008 and March 2009, extracted by the continuous soxhlet extraction using (1:1) hexane-acetone mixture for 24 h and analyzed with a CP 3800 gas chromatogram equipped with {sup 65}Ni electron capture detector (GC-ECD) and a mixed PCBs standard of the ICES 7 as marker, after clean-up. Validation of the efficiency and precision of the extraction and analytical methods were done by extracting samples spiked with 2 ppm ICES PCB standard and a certified reference material 1941b for marine sediments from NIST, USA, and analyzed alongside the samples. Total PCBs detected in sediments during the dry and wet seasons were, respectively, 127 and 112 {mu}g/kg dry weight (dw), with a mean concentration of 120 {mu}g/kg (dw). The composition of PCB homologues in the sediments were dominated by tri-, penta- and tetra-PCBs. There was no correlation between organic carbon (OC) of the sediments and total PCBs content. Risk assessments conducted on the levels indicated that PCB levels in sediments along the coastal region of Ghana poses no significant health risk to humans.

  11. Prediction of chromatographic relative retention time of polychlorinated biphenyls from the molecular electronegativity distance vector.

    PubMed

    Liu, Shu-Shen; Liu, Yan; Yin, Da-Qian; Wang, Xiao-Dong; Wang, Lian-Sheng

    2006-02-01

    Using the molecular electronegativity distance vector (MEDV) descriptors derived directly from the molecular topological structures, the gas chromatographic relative retention times (RRTs) of 209 polychlorinated biphenyls (PCBs) on the SE-54 stationary phase were predicted. A five-variable regression equation with the correlation coefficient of 0.9964 and the root mean square errors of 0.0152 was developed. The descriptors included in the equation represent degree of chlorination (nCl), nonortho index (Ino), and interactions between three pairs of atom types, i.e., atom groups -C= and -C=, -C= and >C=, -C= and -Cl. It has been proved that the retention times of all 209 PCB congeners can be accurately predicted as long as there are more than 50 calibration compounds. In the same way, the MEDV descriptors are also used to develop the five- or six-variable models of RRTs of PCBs on other 18 stationary phases and the correlation coefficients in both modeling stage and LOO cross-validation step are not lower than 0.99 except two models. PMID:16524106

  12. Polychlorinated Biphenyls in Tree Bark near Former Manufacturing and Incineration Facilities in Sauget, Illinois, United States.

    PubMed

    Hermanson, Mark H; Hann, Richard; Johnson, Glenn W

    2016-06-21

    We collected 27 tree bark samples near Sauget, IL, where 373 000 mt of polychlorinated biphenyls (PCB) was produced between 1936 and 1977 and 10 245 mt was incinerated from 1971 to 1977. Our goal was observe PCB distribution and apparent movement to residential sites, where 24 of 27 samples were collected. Only one of several waste sites was accessible for sampling. We analyzed for 209 PCB congeners, and 85 peaks are reported (other congeners either coeluted or were near or less than the detection limit). Concentrations of ∑PCB ranged from 190 952 to 2 383 988 pg g lipid(-1); 24 of 27 samples had less than 50% of the maximum concentration. Two samples with the highest ∑PCB concentrations were downwind from the plant site in residential areas, but both were among the farthest away from the production facility. One high-concentration sample was near the waste site. The three highest concentrations were in trees that were less than 20 years old, showing recent atmospheric PCB mobility. The percentage of ∑PCB distributions showed a consistent but variable pattern of diCB to nonaCB congeners. DecaCB was inconsistent, because PCB-209, which was manufactured at the site in Aroclor 1270 and 1271, was the most abundant congener in 10 of the samples but lower in others. PMID:27182893

  13. Structural properties of platinum(II) biphenyl complexes containing 1,10-phenanthroline derivatives

    NASA Astrophysics Data System (ADS)

    Rillema, D. Paul; Cruz, Arvin J.; Tasset, Brandon J.; Moore, Curtis; Siam, Khamis; Huang, Wei

    2013-06-01

    Seven platinum(II) complexes formulated as Pt(bph)L, where bph is the 2,2'-biphenyl dianion and L = 4-methyl-1,10-phenanthroline (4-Mephen), 5-methyl-1,10-phenanthroline (5-Mephen), 5-chloro-1,10-phenanthroline (5-Clphen), 5,6-dimethyl-1,10-phenanthroline (5,6-Me2phen), 4,7-dimethyl-1,10-phenanthroline (4,7-Me2phen), 4,7-diphenyl-1,10-phenanthroline (4,7-Ph2phen) and 3,4,7,8-tetramethyl-1,10-phenanthroline (3,4,7,8-Me4phen) are reported. Protons attached to the phen ligand resonate downfield from those attached to the bph ligand and two proton signals are split by interaction with 195Pt. Pt(bph)(3,4,7,8-Me4phen), Pt(bph)(4,7-Me2phen), Pt(bph)(5,6-Me2phen), Pt(bph)(4,7-Ph2phen) and Pt(bph)(5-Mephen) crystallize in the space groups Pna21, P21/n, P21/c, P - 1 and Pca21, respectively. The structures of the complexes deviate from true planarity and divide themselves into two groups where the bph and phen ligands cross in an X configuration or bow out in a butterfly (B) configuration. Circular dichroism revealed two different spectra with respect to the X and B configurations.

  14. Polychlorinated biphenyl (PCB) and dichlorodiphenyl dichloroethylene (DDE) concentrations in the breast milk of women in Quebec.

    PubMed Central

    Dewailly, E; Ayotte, P; Laliberté, C; Weber, J P; Gingras, S; Nantel, A J

    1996-01-01

    OBJECTIVES: This study documented the concentration of polychlorinated biphenyls (PCBs) and dichlorodiphenyl dichloroethylene (DDE) in the breast milk of women from Quebec, Canada, and assessed the impact of various sociodemographic and lifestyle factors on these levels. METHODS: From 1988 to 1990, milk samples were obtained from 536 Quebec women and analyzed for seven PCB congeners and p,p'-DDE. Information was obtained on subjects' physical, sociodemographic, and lifestyle characteristics. RESULTS: Mean concentrations were 0.52 mg/kg lipids (95% confidence interval [CI] = 0.50, 0.54) and 0.34 mg/kg lipids (95% CI = 0.32, 0.35) for PCBs (Aroclor 1260) and DDE, respectively. Age and history of breast-feeding showed statistically significant correlations with PCB and DDE concentrations. CONCLUSIONS: Concentrations of PCBs and DDE measured in this study are at the lower end of the concentration range recently reported for women living in industrialized countries. The modulating factors identified here should be considered when conducting studies on organochlorine exposure and disease. PMID:8806375

  15. A simple method for the quantitative microextraction of polychlorinated biphenyls from soils and sediments.

    SciTech Connect

    Szostek, B.; Tinklenberg, J. A.; Aldstadt, J. H., III; Environmental Research

    1999-01-01

    We demonstrate the quantitative extraction of polychlorinated biphenyls (PCBs) from environmental solids by using a microscale adaptation of pressurized fluid extraction ({mu}PFE). The stainless steel extraction cells are filled with a solid sample and solvent and are heated at elevated temperature. After cooling the cell to room temperature, we determined PCBs in the extract by direct injection to a gas chromatograph with an electron capture detection system. This extraction method was tested on a set of PCB-spiked solid matrices and on a PCB-contaminated river sediment (KIST SRM 1939). Recoveries were measured for eight PCB congeners spiked into two soil types with hexane extraction at 100{sup o}C (>81.9 {+-} 5.4% to 112.5 {+-} 10.1 %). The extraction process for SRM 1939 with hexane at 300{sup o}C provided significantly higher recoveries for several representative PCB congeners than reported for a duplicate 16-hour Soy-Wet extraction with a mixture of organic solvents (acetone/hexane).

  16. Polychlorinated biphenyls, mercury, and potential endocrine disruption in fish from the Hudson River, New York, USA

    USGS Publications Warehouse

    Baldigo, Barry P.; Sloan, R.J.; Smith, S.B.; Denslow, N.D.; Blazer, V.S.; Gross, T.S.

    2006-01-01

    Tissue residues of total mercury (Hg), total polychlorinated biphenyls (PCBs), and lipid-based PCBs; plasma concentrations of endocrine biomarkers; and reproductive and histologic biomarkers were assessed in 460 carp (Cyprinus carpio), bass (Micropterus salmoides and Micropterus dolomieui), and bullhead (Ameiurus nebulosus) collected from eight sites across the Hudson River Basin in the spring of 1998 to determine if endocrine disruption was evident in resident fish species and to evaluate contaminant-biomarker interrelations. Total PCBs in bed sediments (maximum 2,500 ??g kg-1) could explain 64 to 90% of the variability in lipid-based PCB residues in tissues (maximum 1,250 ??g PCB g-lipid-1) of the four species. The 17??-estradiol to 11-ketotestosterone ratio, typically less than 1.0 in male fish and greater than 1.0 in females, exceeded 1.4 in all male largemouth bass and 35% of male carp and bullhead at one site 21 km downstream from a major PCB source. Endocrine biomarkers were significantly correlated with total Hg in female smallmouth bass and carp, and with lipid-based PCBs in males of all four species. Empirical evidence of endocrine modulation in blood plasma of male and female fish from sites with and without high PCB residues in bed sediments and fish tissues suggest that PCBs, Hg, or other contaminants may disrupt normal endocrine function in fish of the Hudson River. ?? Eawag, 2006.

  17. Electron transport in asymmetric biphenyl molecular junctions: effects of conformation and molecule-electrode distance

    NASA Astrophysics Data System (ADS)

    Parashar, Sweta; Srivastava, Pankaj; Pattanaik, Manisha; Jain, Sandeep Kumar

    2014-09-01

    On the basis of ab-initio calculations, we predict the effect of conformation and molecule-electrode distance on transport properties of asymmetric molecular junctions for different electrode materials M (M = Au, Ag, Cu, and Pt). The asymmetry in these junctions is created by connecting one end of the biphenyl molecule to conjugated double thiol (model A) and single thiol (model B) groups, while the other end to Cu atom. A variety of phenomena viz. rectification, negative differential resistance (NDR), switching has been observed that can be controlled by tailoring the interface state properties through molecular conformation and molecule-electrode distance for various M. These properties are further analyzed by calculating transmission spectra, molecular orbitals, and orbital energy. It is found that Cu electrode shows significantly enhanced rectifying performance with change in torsion angles, as well as with increase in molecule-electrode distances than Au and Ag electrodes. Moreover, Pt electrode manifests distinctive multifunctional behavior combining switch, diode, and NDR. Thus, the Pt electrode is suggested to be a good potential candidate for a novel multifunctional electronic device. Our findings are compared with available experimental and theoretical results. Supplementary material in the form of one pdf file available from the Journal web page at http://http//dx.doi.org/10.1140/epjb/e2014-50133-2

  18. Immunoassay screening of sediment cores for polychlorinated biphenyls, Devil's Swamp Lake near Baton Rouge, Louisiana, 2004

    USGS Publications Warehouse

    Van Metre, Peter C.; Wilson, Jennifer T.

    2004-01-01

    Devil?s Swamp Lake near Baton Rouge, Louisiana, constructed by dredging in 1973 in Devil?s Swamp along the Mississippi River, is contaminated with polychlorinated biphenyls (PCBs). This study investigated the possible historical contribution of PCBs from a hazardous-chemical disposal facility by way of a wastewater drainage ditch that operated from 1971 to 1993. Six sediment cores from the lake and three bottom-material samples from the drainage ditch were collected on October 5, 2004, and analyzed for PCBs using an immunoassay screening method. The results were used to evaluate qualitatively the historical input record of PCBs to the lake. Deposition dates in three of the cores were estimated by assuming that penetration of the push corer was stopped by firmer, pre-lake materials that mark the 1973 subsurface level of dredging. Sixty-one samples from five of the six cores and three bottom-material samples from the drainage ditch were analyzed. PCBs were at higher concentrations in ditch bottom material (about 1.1 to 2.2 milligrams per kilogram) than in cores from sites near where the ditch enters the lake (about 0.1 to 1.0 milligrams per kilogram). The highest concentrations of PCBs (maximum about 15 milligrams per kilogram) were detected in lake-bottom sediment about 350 meters west of where the drainage ditch enters the lake. Detection rates and median PCB concentrations were higher in all of the dated core sediments deposited before about 1990 than after 1990.

  19. Clearance of Polychlorinated Biphenyl Atropisomers is Enantioselective in Female C57Bl/6 Mice

    PubMed Central

    Kania-Korwel, Izabela; El-Komy, Mohammed H.M.E.; Veng-Pedersen, Peter; Lehmler, Hans-Joachim

    2009-01-01

    Changes in the enantiomer composition of polychlorinated biphenyls (PCBs) can not only be used to investigate environmental and biological transport processes, but also has human health implications because of enantiospecific adverse health effects. To further understand differences in the disposition of PCB atropisomers in vivo, the present study investigates the toxicokinetics of PCB atropisomers in female C57Bl/6 mice after oral administration of a mixture of several PCBs, including racemic PCBs 95, 132, 136, 149, 174 and 176. On the Chirasil-Dex column, an enrichment of the second eluting atropisomers was generally observed, whereas only the first eluting atropisomers E1-PCB 95, (−)-PCB 132 and (−)-PCB 149 had half-lives that were distinctively longer compared to the second eluting atropisomers. The bioavailability normalized clearance of first eluting atropisomers in blood was faster compared to second eluting atropisomers. The opposite trend was observed for the accumulation factors in adipose tissue, which is consistent with the slower clearance of the first eluting atropisomer. The only exception was PCB 174, which showed no differences in the toxicokinetic parameters of both atropisomers. Together, the differences in the toxicokinetics of PCB atropisomers point towards enantioselective biotransformation processes as the origin of PCB’s enantiomeric enrichment in mammals and, possibly, humans. PMID:20384376

  20. Assessing ongoing sources of dissolved-phase polychlorinated biphenyls in a contaminated stream

    USGS Publications Warehouse

    Dang, Viet D.; Walters, David M.; Lee, Cindy M.

    2013-01-01

    Few studies assess the potential of ongoing sources of “fresh” polychlorinated biphenyls (PCBs) to aquatic systems when direct discharge to the environment has been eliminated. In the present study, the authors used single-layered, low-density polyethylene samplers (PEs) to measure total PCB concentrations, congener profiles, and enantiomeric fractions (EFs) in a contaminated stream and to provide multiple lines of evidence for assessing ongoing inputs of PCB. Concentrations were well above background levels that have been monitored for years. Concentrations significantly increased with distance, the farthest downstream PE concentrations being almost five times greater than those at 79 m downstream of a historical point source. The PCBs in the PEs at 79 m downstream of the contamination source were dominated by low KOW congeners, similar to those in the mixture of Aroclors 1016 and 1254 (4:1 v/v) historically released from the former capacitor manufacturer. The only two chiral congeners detected in the PEs downstream were PCBs 91 and 95. The EF values were nonracemic for PCB 91, while the values were either racemic or near racemic for PCB 95. Increased PCB concentrations with distance and a congener composition of predominantly low-weight congeners in the PEs at 79 m downstream of the plant site suggested an ongoing PCB source from the plant site. Chiral signatures suggested aerobic biotransformation of dissolved PCBs but did not shed any light on possible ongoing PCB inputs.

  1. Assessing atmospheric concentration of polychlorinated biphenyls (PCBs) by evergreen Rhododendron maximum next to a contaminated stream

    USGS Publications Warehouse

    Dang, Viet D.; Walters, David; Lee, Cindy M.

    2016-01-01

    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 this study, we used Rhododendron maximum (rhododendron) growing next to a contaminated stream to assess atmospheric PCB concentrations. The study area was located in a rural setting and approximately 2 km downstream of a former Sangamo-Weston (S-W) plant. Leaves from the same mature shrubs were collected in late fall 2010, and winter and spring 2011. PCBs 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, 2850, 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 S-W plant. Leaves had a consistent pattern of high concentrations of tetra- and penta-CBs similar to the congener distribution in polyethylene (PE) passive samplers deployed in the water column suggesting that volatilized PCBs from the stream were the primary source of contaminants in rhododendron leaves.

  2. Persistent or not persistent? Polychlorinated biphenyls are readily depurated by grizzly bears (Ursus arctos horribilis).

    PubMed

    Christensen, Jennie R; Letcher, Robert J; Ross, Peter S

    2009-10-01

    Major pharmacokinetic processes influencing polychlorinated biphenyl (PCB) accumulation in mammals include uptake, biotransformation, respiration, and excretion. We characterized some of the factors underlying PCB accumulation/loss by evaluating PCB concentrations and patterns in pre- and posthibernation grizzly bears (Ursus arctos horribilis) and their prey. The PCB congeners with vicinal meta- and para-chlorine unsubstituted hydrogen positions consistently showed loss both before and during hibernation, supporting the idea of a dominant role for biotransformation. Retention of all other studied congeners relative to that of PCB 194 varied widely (from <1 to 100%) and was highly correlated with log octanol-water partition coefficient (p < 0.0001). A lack of loss for most of these other congeners during hibernation supports the notion that excretion (e.g., fecal or urinary) or lack of uptake during the feeding season underlies their lack of accumulation, because hibernating bears do not eat or excrete. We estimate that grizzly bears retain less than 10% of total PCBs taken up from their diet. Our results suggest that for grizzly bears, depuration of PCBs via biotransformation is important (explaining approximately 40% of loss), but that nonbiotransformation processes, such as excretion, may be more important (explaining approximately 60% of loss). These findings, together with the approximately 91% loss of the persistent PCB 153 congener relative to PCB 194 in grizzly bears, raise important questions about how one defines persistence of PCBs in wildlife and may have bearing on the interpretation of food-web biomagnification studies. PMID:19480534

  3. Courtship behavior of captive American kestrels (Falco sparverius) exposed to polychlorinated biphenyls.

    PubMed

    Fisher, S A; Bortolotti, G R; Fernie, K J; Smits, J E; Marchant, T A; Drouillard, K G; Bird, D M

    2001-08-01

    Polychlorinated biphenyls (PCBs) adversely affect reproduction in birds. Captive adult male and female American kestrels (Falco sparverius) were studied to investigate the potential behavioral and hormonal alterations during the courtship period resulting from clinical exposure to PCBs. American kestrels ingested 7 mg/kg/body weight/bird/day of a 1:1:1 mixture of Aroclors 1248, 1254, and 1260 through their diet of day-old cockerels. The dietary dosage of Aroclors resulted in environmentally relevant total PCB residues in the eggs, averaging 34.1 microg/g wet weight (geometric mean). There was no difference between treatment and control birds in the circulating levels of total androgens (p = 0.44) or in 17 beta-estradiol (p = 0.29), one week following pairing. Male kestrels exposed to dietary PCBs exhibited significantly more sexual behaviors (p = 0.034) and flight behaviors (p = 0.026) than the control males. Sexual behaviors of male kestrels included; nest-box inspections, solicitation of copulation, the offer of food to the female, and giving the female food. The flight behaviors of the male included; flying from one perch to another and aerial display. In addition, the frequency of male sexual behaviors were correlated (r = 0.605, p = 0.001) with total PCB residues in the eggs of their mates. A concurrent study found that these same PCB-exposed kestrels experienced a delay in clutch initiation as well as a greater number of completely infertile clutches. PMID:11462146

  4. Dechlorination of polychlorinated biphenyls in industrial transformer oil by radiolytic and photolytic methods.

    PubMed

    Jones, Cynthia G; Silverman, Joseph; Al-Sheikhly, Mohamad; Neta, Pedatsur; Poster, Dianne L

    2003-12-15

    Used electrical transformer oils containing low or high concentrations of polychlorinated biphenyls (PCBs) were treated using electron, gamma, and ultraviolet radiation, and the conditions for complete dechlorination were developed. Dechlorination was determined by analysis of the inorganic chloride formed and the concentrations of remaining PCBs. Transformer oil containing approximately 95 microg g(-1) PCB (approximately 3.5 mmol L(-1) Cl) is completely dechlorinated by irradiation with 600 kGy after the addition of 10% triethylamine (TEA). Transformer oil containing >800,000 microg g(-1) PCB (17.7 mol L(-1) Cl) requires an additional solvent to prevent solidification. When this oil is diluted with 2-propanol (2-PrOH) and TEA (v/v/v, 1/79/20), complete dechlorination is achieved with a dose of 2500 kGy. Ultraviolet photolysis of the same oil/2-PrOH/TEA solutions led to 90% dechlorination after exposure for 120 h in our experimental setup. Such yields were obtained by radiolysis with a dose of 2000 kGy (300 h in our Gammacell). Replacing TEA with KOH in 2-PrOH solutions greatly increases the yield of dechlorination in both the radiolytic and the photolytic experiments, demonstrating that a chain reaction plays a role in both of these treatment methods and suggesting that both methods deserve further consideration for large-scale application. PMID:14717194

  5. Gas chromatographic and mass spectrometric analysis of polychlorinated biphenyls in human placenta and cord blood

    SciTech Connect

    Ando, M.; Saito, H.; Wakisaka, I.

    1986-10-01

    Gas chromatographic and mass spectrometric analyses of polychlorinated biphenyls (PCBs) in placenta, maternal blood, cord blood, and milk were carried out. Trichlorobiphenyl, tetrachlorobiphenyl, pentachlorobiphenyls, and hexachlorobiphenyls were identified by the mass chromatogram and the mass spectra. Some minor peaks of PCBs were identified by gas chromatography. The relationship between the PCB concentration in placenta and that in milk is different in each PCB congener. The higher the chlorine content of the PCB congener, the more significant the correlation. No significant but a low negative correlation exists between the concentration of some PCB congeners in the placenta and that in cord blood. On the other hand, a significant linear correlation exists between the concentration of hexachlorobenzene in the placenta and that in cord blood. The transplacental transport of each PCB congener varied depending upon its chemical nature. Trichlorobiphenyl and tetrachlorobiphenyl were more transferable than hexachlorobiphenyls. The results show that the placenta and cord blood are useful human samples to analyze the body burden of environmental pollutants and to estimate their transfer from mother to fetus.

  6. Polychlorinated biphenyl contamination of the spider crab (Maja brachydactyla): influence of physiological and ecological processes.

    PubMed

    Bodin, Nathalie; Caisey, Xavier; Abarnou, Alain; Loizeau, Véronique; Latrouite, Daniel; Le Guellec, Anne-Marie; Guillou, Monique

    2007-03-01

    Maja brachydactyla is a decapod crustacean widely distributed along the Northeast Atlantic coasts. The main objective of this work was to establish the influence of ontogenic factors, such as growth, aging, seasonal migrations, and reproduction, on the contamination of this species by polychlorinated biphenyls (PCBs). Two populations were studied: One in the Seine Bay (Eastern English Channel), which is exposed to greatly contaminated discharges from the Seine River, and one in the Iroise Sea (Western Brittany), which is little contaminated by such man-made compounds. At both sampling areas, PCB analysis revealed concentrations in hepatopancreas that were 10- and 50-fold higher than concentrations in gonads and muscle, respectively. Levels of 2,2',4,4',5,5'-hexachlorobiphenyl (CB153) increased with the age of the spider crabs, whereas their seasonal migrations had no direct effect. No significant sex effect was observed with regards to CB153 levels, but adult females exhibited PCB fingerprints different from those of males, probably because of the influence of the reproductive cycle on enzymatic system activity. Finally, spawning gave rise to a higher CB153 decontamination of female body burdens for specimens from the Iroise Sea than for those from the Seine Bay. PMID:17373508

  7. Age-related polychlorinated biphenyl dynamics in immature bull sharks (Carcharhinus leucas).

    PubMed

    Olin, Jill A; Beaudry, Marina; Fisk, Aaron T; Paterson, Gordon

    2014-01-01

    Polychlorinated biphenyls (PCBs) were quantified in liver tissues of bull sharks (Carcharhinus leucas) ranging in age from <4 wk to >3 yr. Summed values of PCBs (ΣPCBs) ranged from 310 ng/g to 22 070 ng/g (lipid wt) across age classes with ΣPCB concentrations for the youngest sharks in the present study (<4 wk; 5230 ± 2170 ng/g lipid wt) determined to not significantly differ from those quantified in >3-yr-old sharks, highlighting the extent of exposure of this young life stage to this class of persistent organic pollutants (POPs). Age normalization of PCB congener concentrations to those measured for the youngest sharks demonstrated a significant hydrophobicity (log octanol/water partition coefficient [KOW ]) effect that was indicative of maternal offloading of highly hydrophobic (log KOW ≥6.5) congeners to the youngest individuals. A distinct shift in the PCB congener profiles was also observed as these young sharks grew in size. This shift was consistent with a transition from the maternally offloaded signal to the initiation of exogenous feeding and the contributions of mechanisms including growth dilution and whole-body elimination. These results add to the growing pool of literature documenting substantially high concentrations of POPs in juvenile sharks that are most likely attributable to maternal offloading. Collectively, such results underscore the potential vulnerability of young sharks to POP exposure and pose additional concerns for shark-conservation efforts. PMID:24357032

  8. Sex difference in polychlorinated biphenyl concentrations of burbot Lota lota from Lake Erie

    USGS Publications Warehouse

    Madenjian, C.P.; Stapanian, M.A.; Rediske, R.R.; O’Keefe, J. P.

    2013-01-01

    Whole-fish polychlorinated biphenyl (PCB) concentrations were determined for 25 female and 25 male burbot Lota lota from Lake Erie. Bioenergetics modeling was used to investigate whether the sex difference in growth rate resulted in a difference in gross growth efficiency (GGE) between the sexes. For ages 6–13 years, male burbot averaged 28 % greater PCB concentrations than female burbot. The sex difference in PCB concentrations widened for ages 14–17 years, with male burbot having, on average, 71 % greater PCB concentrations than female burbot. Bioenergetics modeling results showed that the faster growth rate exhibited by female burbot did not lead to greater GGE in female individuals of the younger burbot and that the faster growth by female fish led to female GGE being only 2 % greater than male GGE in older burbot. Although our bioenergetics modeling could not explain the observed sex difference in PCB concentrations, we concluded that a sex difference in GGE was the most plausible explanation for the sex difference in PCB concentrations of burbot ages 6–13 years. Not only are male fish likely to be more active than female fish, but the resting metabolic rate of male fish may be greater than that of female fish. We also concluded that the widening of the sex difference in PCB concentrations for the older burbot may be due to many of the older male burbot spending a substantial amount of time in the vicinity of mouths of rivers contaminated with PCBs.

  9. Sexual difference in polychlorinated biphenyl accumulation rates of walleye (Stizostedion vitreum)

    USGS Publications Warehouse

    Madenjian, Charles P.; Noguchi, George E.; Haas, Robert C.; Schrouder, Kathrin S.

    1998-01-01

    Adult male walleye (Stizostedion vitreum) exhibited significantly higher polychlorinated biphenyl (PCB) concentrations than similarly aged female walleye from Saginaw Bay (Lake Huron). To explain this difference, we tested the following three hypotheses: (i) females showed a considerably greater reduction in PCB concentration immediately following spawning than males, (ii) females grew at a faster rate and therefore exhibited lower PCB concentrations than males, and (iii) males spent more time in the Saginaw River system than females, and therefore received a greater exposure to PCBs. The first hypothesis was tested by comparing PCB concentration in gonadal tissue with whole-body concentration, the second hypothesis was tested via bioenergetics modeling, and we used mark-recapture data from the Saginaw Bay walleye fishery to address the third hypothesis. The only plausible explanation for the observed difference in PCB accumulation rate was that males spent substantially more time in the highly contaminated Saginaw River system than females, and therefore were exposed to greater environmental concentrations of PCBs. Based on the results of our study, we strongly recommend a stratified random sampling design for monitoring PCB concentration in Saginaw Bay walleye, with fixed numbers of females and males sampled each year.

  10. Photocatalytic removal of polychlorinated biphenyls (PCBs) using carbon-modified titanium oxide nanoparticles

    NASA Astrophysics Data System (ADS)

    Shaban, Yasser A.; El Sayed, Mohamed A.; El Maradny, Amr A.; Al Farawati, Radwan Kh.; Al Zobidi, Mosa I.; Khan, Shahed U. M.

    2016-03-01

    In this work, the sonicated sol-gel method was used for synthesizing carbon-modified titanium oxide nanoparticles. Carbon incorporation was achieved by using titanium (IV) isopropoxide as a titanium and carbon-containing precursor. The photocatalytic efficiency of the synthesized photocatalyst was assessed by examining the photocatalytic removal of polychlorinated biphenyls (PCBs) from aqueous solution. For comparison, unmodified (regular) titanium dioxide (n-TiO2) was used as a reference catalyst. To confirm the carbon incorporation in CM-n-TiO2 nanoparticles, energy dispersive spectroscopy (EDS) analysis was used. Significantly, the bandgap energy was found to be reduced from 2.99 eV for n-TiO2 to 1.8 eV for CM-n-TiO2, which in turn improved the performance of CM-n-TiO2 toward the photocatalytic removal of PCBs. The effects of CM-n-TiO2 loading, PCBs concentration, and pH of the solution on the photodegradation rate of PCBs were investigated. The highest removal rate was found to be at pH 5 and CM-n-TiO2 loading of 0.5 g L-1. According to Langmuir-Hinshelwood model, the photodegradation of PCBs using CM-n-TiO2 followed a pseudo-first order reaction kinetics.

  11. Bioaccumulation patterns of polychlorinated biphenyls and chlorinated pesticides in northwest Atlantic pilot whales

    SciTech Connect

    Weisbrod, A.V.; Shea, D.; Moore, M.J.; Stegeman, J.J.

    2000-03-01

    Contaminant exposure is widespread among marine mammals but is of unknown significance. This study characterized organochlorine bioaccumulation in pilot whales, and these bioaccumulation patterns are proposed as representative of Northwest (NW) Atlantic cetacea. Samples were collected from whales stranded in Massachusetts and caught in nets. Polychlorinated biphenyl (PCB) and chlorinated pesticide concentrations were determined via GC/ECD and found to be similar to those reported for other NW Atlantic odontocetes. The organochlorine in highest concentration was 4,4{prime}-DDE, followed by trans-nonachlor, 4,4{prime}-DDD, dieldrin, cis-chlordane, C14(52), C15(95), C15(101), C15(118), C16(138), C16(149), C16(153), C17(180), and C17(187). The concentration of 19 pesticides was higher in blubber than liver. The concentration of 26 PCB congeners was also greater in blubber than liver. Principal component analysis and ANOVA indicated that blubber accumulated proportionately more of the most recalcitrant compounds, such as 4,4{prime}-DDE and nonmetabolizable PCBs, compared to liver. Whales that stranded together had more similar bioaccumulation than animals of the same gender or maturity. The high variation among individuals in tissue concentrations and the similarity within a stranding group suggest that pilot whale pods are exposed to a large range of pollutant sources, such as through different prey and feeding locations.

  12. Increased deposition of polychlorinated biphenyls (PCBs) under an AC high-voltage power line

    NASA Astrophysics Data System (ADS)

    Öberg, Tomas; Peltola, Pasi

    2009-12-01

    There is considerable public concern regarding the potential risks to health of electromagnetic fields in general and high-voltage power lines in particular. As epidemiological findings are not supported by a clearly defined mechanism of direct magnetic field interactions with the human body, potential indirect effects are of interest. It has been suggested that an increased exposure to chemical pollutants could occur near high-voltage power lines due to formation and deposition of charged aerosols. The current study reports empirical evidence that seems to support this hypothesis. The deposition of 18 congeners of polychlorinated biphenyls (PCBs) was studied by collecting samples of pine needles under a 400 kV AC power line and at reference sites in the vicinity. Compared to the reference sites, the average deposition of PCB congeners under the power line was almost double. This difference between the two groups of samples was statistically significant. While it is premature to draw any conclusions regarding the human exposure near high-voltage power lines, the issue deserves attention and further investigations.

  13. Primary source regions of polychlorinated biphenyls (PCBs) measured in the Arctic

    NASA Astrophysics Data System (ADS)

    Ubl, Sandy; Scheringer, Martin; Stohl, Andreas; Burkhart, John F.; Hungerbuhler, Konrad

    2012-12-01

    We investigate the source regions of the three polychlorinated biphenyl congeners (PCBs) 28, 101, and 180 measured at the Arctic stations Alert and Zeppelin, and at Birkenes, which is located in southern Norway. Although the Arctic is remote from the main use areas of these chemicals, PCBs have been found in Arctic air, seawater and biota, which has caused concerns for human and environmental health. We used 20-day backward calculations of the Lagrangian Particle Dispersion Model FLEXPART to identify the origin of air masses associated with the 20% highest and lowest measured PCB concentrations. At Birkenes, high concentrations are clearly associated with air masses arriving from known source regions (primarily in Europe and Russia), whereas low concentrations are correlated with atmospheric transport from regions with low primary emissions. At Zeppelin, the influence from known source regions is also enhanced when high PCB-28 and PCB-101 concentrations were measured. At Alert, in contrast, there is no clear link between high/low PCB concentrations and atmospheric transport from source/non-source regions. Additionally, we combined the atmospheric transport patterns with PCB emission data to identify important source regions and their seasonal variability. For the Arctic stations, Western Russia is the dominant source region for PCB-28 and PCB-101. Central Europe is the most important source region for PCB-180, but sources in the US contribute up to 15% to PCB-180 measured at Alert.

  14. Forecasting long-range atmospheric transport episodes of polychlorinated biphenyls using FLEXPART

    NASA Astrophysics Data System (ADS)

    Halse, Anne Karine; Eckhardt, Sabine; Schlabach, Martin; Stohl, Andreas; Breivik, Knut

    2013-06-01

    The analysis of concentrations of persistent organic pollutants (POPs) in ambient air is costly and can only be done for a limited number of samples. It is thus beneficial to maximize the information content of the samples analyzed via a targeted observation strategy. Using polychlorinated biphenyls (PCBs) as an example, a forecasting system to predict and evaluate long-range atmospheric transport (LRAT) episodes of POPs at a remote site in southern Norway has been developed. The system uses the Lagrangian particle transport model FLEXPART, and can be used for triggering extra ("targeted") sampling when LRAT episodes are predicted to occur. The system was evaluated by comparing targeted samples collected over 12-25 h during individual LRAT episodes with monitoring samples regularly collected over one day per week throughout a year. Measured concentrations in all targeted samples were above the 75th percentile of the concentrations obtained from the regular monitoring program and included the highest measured values of all samples. This clearly demonstrates the success of the targeted sampling strategy.

  15. Application of a Tenax model to assess bioavailability of polychlorinated biphenyls in field sediments.

    PubMed

    Mackenbach, Elizabeth M; Harwood, Amanda D; Mills, Marc A; Landrum, Peter F; Lydy, Michael J

    2014-02-01

    Recent literature has shown that bioavailability-based techniques, such as Tenax extraction, can estimate sediment exposure to benthos. In a previous study by the authors, Tenax extraction was used to create and validate a literature-based Tenax model to predict oligochaete bioaccumulation of polychlorinated biphenyls (PCBs) from sediment; however, its ability to assess sediment remediation was unknown. The present study further tested the Tenax model by examining the impacts of remediation on surface sediment concentrations, Tenax extractable concentrations, and tissue concentrations of laboratory-exposed Lumbriculus variegatus. Tenax extractable concentration was an effective exposure metric to evaluate changes in Lumbriculus exposure preremediation and postremediation, with 75% of the postremediation data corresponding to the Tenax model. At nondredged sites, bioaccumulation was better predicted by the Tenax model, with 86% of the data falling within the 95% confidence intervals, than at dredged sites, for which only 64% of the data fit the Tenax model. In both pre- and postdredge conditions, when the model failed, it was conservative, predicting higher PCB concentrations than observed in the oligochaetes, particularly for the postdredge data. The present study advances understanding of the applicability of the Tenax model for use when examining systems that may have undergone significant disturbances. The Tenax model provides a unique tool for quickly quantifying potential exposure to benthic organisms. PMID:24127319

  16. QSAR studies of benzofuran/benzothiophene biphenyl derivatives as inhibitors of PTPase-1B

    PubMed Central

    Kaushik, D.; Kumar, R.; Saxena, A. K.

    2010-01-01

    Objectives: Insulin resistance is associated with a defect in protein tyrosine phosphorylation in the insulin signal transduction cascade. The PTPase enzyme dephosphorylates the active form of the insulin receptor and thus attenuates its tyrosine kinase activity, therefore, the need for a potent PTPase inhibitor exists, with the intention of which the QSAR was performed. Materials and Methods: Quantitative structure-activity relationship (QSAR) has been established on a series of 106 compounds considering 27 variables, for novel biphenyl analogs, using the SYSTAT (Version 7.0) software, for their protein tyrosine phosphatase (PTPase-1B) inhibitor activity, in order to understand the essential structural requirement for binding with the receptor. Results: Among several regression models, one per series was selected on the basis of a high correlation coefficient (r, 0.86), least standard deviation (s, 0.234), and a high value of significance for the maximum number of subjects (n, 101). Conclusions: The influence of the different physicochemical parameters of the substituents in various positions has been discussed by generating the best QSAR model using multiple regression analysis, and the information thus obtained from the present study can be used to design and predict more potent molecules as PTPase-1B inhibitors, prior to their synthesis. PMID:21814427

  17. Radiation induced degradation of polychlorinated biphenyls (PCBs) pollutants in paint scrapings.

    PubMed

    Singh, R K; Khandal, R K; Singh, Gurdeep

    2009-01-01

    Polychlorinated biphenyls (PCBs) are synthetic organic chemicals which have been commercially used worldwide in many specialty applications. In paints, PCBs were used because of their unique properties such as thermal stability, flame-resistance and low volatility. However, due to their adverse effects on human health and environment, the use of PCBs has now been banned. PCBs are today considered widespread pollutants in the global system . PCBs sources still exist in various products and in waste streams such as oil, paints, rubbers etc. Various remedial technologies have been developed in the world to detoxify PCBs. In the present study, radiolysis has been investigated as a safe means to reduce or destroy PCBs. Under this study, detoxification of PCBs in paint scrapings by gamma radiation using Cobalt 60 source has been investigated. The experimental results demonstrate that the gamma radiations can be an alternative environment- friendly technology for destroying PCBs. Gamma radiations also have the potential of being a preferred tool in comparison to the most widely used incineration method for destroying PCBs. The method used was found highly effective and destruction efficiency was as high as 91%. The degradation efficiency of PCBs was dependent on absorbed radiation dose, the type of PCBs and also on the source of paint scrapings. PMID:21114157

  18. Label-free impedimetric immunoassay for trace levels of polychlorinated biphenyls in insulating oil.

    PubMed

    Date, Yasumoto; Aota, Arata; Sasaki, Kazuhiro; Namiki, Yukie; Matsumoto, Norio; Watanabe, Yoshitomo; Ohmura, Naoya; Matsue, Tomokazu

    2014-03-18

    A rapid, ultrasensitive, and practical label-free impedimetric immunoassay for measuring trace levels of total polychlorinated biphenyls (PCBs) in insulating oil was developed. First, we developed a novel monoclonal antibody (RU6F9) for PCBs by using a designed immunogen and characterized its binding affinity for a commercial mixtures of PCBs and its main congeners. A micro comblike gold electrode was fabricated, and the antibody was covalently immobilized on the electrode through a self-assembled monolayer formed by dithiobis-N-succinimidyl propionate. The antigen-binding event on the surface of the functionalized electrode was determined as the change in charge transfer resistance by using electrochemical impedance spectroscopy. The resulting impedimetric immunoassay in aqueous solution achieved a wide determination range (0.01-10 μg/L) and a low detection limit (LOD) of 0.001 μg/L, which was 100-fold more sensitive than a conventional flow-based immunoassay for PCBs. By combining the impedimetric immunoassay with a cleanup procedure for insulating oil utilizing a multilayer cleanup column followed by DMSO partitioning, an LOD of 0.052 mg/kg-oil was achieved, which satisfied the Japanese regulation criterion of 0.5 mg/kg-oil. Finally, the immunoassay was employed to determine total PCB levels in actual used insulating oils (n = 33) sampled from a used transformer containing trace levels of PCBs, and the results agreed well with the Japanese official method (HRGC/HRMS). PMID:24528234

  19. Distribution of polychlorinated biphenyls in the Housatonic River and adjacent aquifer, Massachusetts

    USGS Publications Warehouse

    Gay, Frederick B.; Frimpter, Michael H.

    1985-01-01

    Polychlorinated biphenyls (PCB's) are sorbed to the fine-grained stream-bottom sediments along the Housatonic River from Pittsfield, Massachusetts, southward to the Massachusetts-Connecticut boundary. The highest PCB concentrations, up to 140,000 micrograms per kilogram, were found in samples of bottom material from a reach of the river between Pittsfield and Woods Pond Dam in Lee, Massachusetts. Sediments in Woods Pond have been estimated to contain about 11,000 pounds of PCB's. Approximately 490 pounds per year of PCB's have also been estimated to move past the Housatonic River gaging station at Great Barrington. The distribution of hydraulic heads, water temperatures, and concentrations of dissolved oxygen, ammonia, nitrate, iron, and manganese in ground water shows that industrial water-supply wells in a sand and gravel aquifer adjacent to a stretch of the river called Woods Pond have been inducing ground-water recharge through the PCB-contaminated bottom sediments of the pond since late 1956. These data indicate that, at one location along the shore of the pond, the upper 40 feet of the aquifer contains water derived from induced infiltration. However, this induced recharge has not moved PCB's from the bottom sediments into a vertical section of the aquifer located 5 feet downgradient from the edge of Woods Pond. Samples taken at selected intervals in this section showed that no PCB's sorbed to the aquifer material or dissolved in the ground water within the detection limits of the chemical analyses.

  20. Effects of embryonic exposure to polychlorinated biphenyls (PCBs) on larval zebrafish behavior.

    PubMed

    Lovato, Ava K; Creton, Robbert; Colwill, Ruth M

    2016-01-01

    Developmental disorders such as anxiety, autism, and attention deficit hyperactivity disorders have been linked to exposure to polychlorinated biphenyls (PCBs), a ubiquitous anthropogenic pollutant. The zebrafish is widely recognized as an excellent model system for assessing the effects of toxicant exposure on behavior and neurodevelopment. In the present study, we examined the effect of sub-chronic embryonic exposure to the PCB mixture, Aroclor (A) 1254 on anxiety-related behaviors in zebrafish larvae at 7 days post-fertilization (dpf). We found that exposure to low concentrations of A1254, from 2 to 26 h post-fertilization (hpf) induced specific behavioral defects in two assays. In one assay with intermittent presentations of a moving visual stimulus, 5 ppm and 10 ppm PCB-exposed larvae displayed decreased avoidance behavior but no significant differences in thigmotaxis or freezing relative to controls. In the other assay with intermittent presentations of a moving visual stimulus and a stationary visual stimulus, 5 ppm and 10 ppm PCB-exposed larvae had elevated baseline levels of thigmotaxis but no significant differences in avoidance behavior relative to controls. The 5 ppm larvae also displayed higher terminal levels of freezing relative to controls. Collectively, our results show that exposure to ecologically valid PCB concentrations during embryonic development can induce functional deficits and alter behavioral responses to a visual threat. PMID:26561944