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Sample records for biphenyl compounds

  1. Separation of Biphenyl Nitrile Compounds by Microemulsion Electrokinetic Chromatography with Mixed Surfactants

    Institute of Scientific and Technical Information of China (English)

    Su Xuan GONG; Tao BO; Lan HUANG; Ke An LI; Hu Wei LIU

    2004-01-01

    A mixture of nine biphenyl nitrile compounds with high hydrophobicity and similar structures was successfully separated by microemulsion electrokinetic chromatography (MEEKC) within 30 min. The buffer system contained 100 mmol/L sodium dodecyl sulfate (SDS), 80 mmol/L sodium cholate (SC), 0.81% heptane, 7.5% n-butanol, 10% acetonitrile and 10 mmol/L borate. The addition of SC, organic modifiers, sample preparation and temperature all showed remarkable effect on the separation. Meanwhile, the MEEKC method was briefly compared with micellar electrokinetic chromatography (MEKC) method.

  2. Analytical methods for phenyltin compounds in polychlorinated biphenyl-based transformer oil samples.

    Science.gov (United States)

    Yamamoto, Takashi; Noma, Yukio; Yasuhara, Akio; Sakai, Shin-ichi

    2003-10-31

    We present the first study on the analytical methods of phenyltin compounds (PTs) in polychlorinated biphenyl (PCB)-based transformer oil samples. Tetraphenyltin (TePhT) has been used as stabilizer for some kinds of PCBs-based transformer oil formulations. Monophenyltin (MPhT), diphenyltin (DPhT) and triphenyltin (TrPhT) could have been formed from TePhT during long-term use. TePhT was directly measured by gas chromatograph (GC) connected with three types of detectors, a mass spectrometer (MS), a flame photometric detector (FPD) and an atomic emission detector (AED) after dilution with hexane. MPhT, DPhT and TrPhT were propylated with Grignard reagent before measurement. The MS was the most sensitive of the detectors, with detection limits of phenyltin compounds of 30 ng/ml (MPhT), 9.8 ng/ml (DPhT), 5.5 ng/ml (TrPhT) and 0.60 ng/ml (TePhT), respectively. From the viewpoint of selectivity, MS was slightly worse than other detectors, but interference from PCBs matrices was not significant under ordinary analytical conditions. Two used transformer oil samples were analyzed using the analytical methods developed in this study. TePhT and TrPhT were found in both samples.

  3. Polybrominated dibenzo-p-dioxins, dibenzofurans, and biphenyls: inclusion in the toxicity equivalency factor concept for dioxin-like compounds.

    Science.gov (United States)

    van den Berg, Martin; Denison, Michael S; Birnbaum, Linda S; Devito, Michael J; Fiedler, Heidelore; Falandysz, Jerzy; Rose, Martin; Schrenk, Dieter; Safe, Stephen; Tohyama, Chiharu; Tritscher, Angelika; Tysklind, Mats; Peterson, Richard E

    2013-06-01

    In 2011, a joint World Health Organization (WHO) and United Nations Environment Programme (UNEP) expert consultation took place, during which the possible inclusion of brominated analogues of the dioxin-like compounds in the WHO Toxicity Equivalency Factor (TEF) scheme was evaluated. The expert panel concluded that polybrominated dibenzo-p-dioxins (PBDDs), dibenzofurans (PBDFs), and some dioxin-like biphenyls (dl-PBBs) may contribute significantly in daily human background exposure to the total dioxin toxic equivalencies (TEQs). These compounds are also commonly found in the aquatic environment. Available data for fish toxicity were evaluated for possible inclusion in the WHO-UNEP TEF scheme (van den Berg et al., 1998). Because of the limited database, it was decided not to derive specific WHO-UNEP TEFs for fish, but for ecotoxicological risk assessment, the use of specific relative effect potencies (REPs) from fish embryo assays is recommended. Based on the limited mammalian REP database for these brominated compounds, it was concluded that sufficient differentiation from the present TEF values of the chlorinated analogues (van den Berg et al., 2006) was not possible. However, the REPs for PBDDs, PBDFs, and non-ortho dl-PBBs in mammals closely follow those of the chlorinated analogues, at least within one order of magnitude. Therefore, the use of similar interim TEF values for brominated and chlorinated congeners for human risk assessment is recommended, pending more detailed information in the future.

  4. Enantiomer Separation of α-Dimethyl Dicarboxylate Biphenyl and Related Biphenyl Compounds by Normal Phase HPLC on Polysaccharide Based Chiral Stationary Phases

    Institute of Scientific and Technical Information of China (English)

    LIU,Yue-Qi(刘月启); HAN,Xiao-Qian(韩小茜); Qi,Bang-Feng(齐邦峰); LIU,Chun-Hui(柳春辉); LI,Yong-Min(李永民); CHEN,Li-Ren(陈立仁)

    2002-01-01

    Cellulose tris(4-methylphenylcarbamate), amylose tris(3,5-dimethylpphenylcarbamate) and amylose tris (phenylcarbamate)were prepared by the method reported by Okamoto and were coated onto an aminopropylated mesoporous spherical silica gel. These final products were used as chiral stationary phases of high performance liquid chromatography for the eighteen structurally related biphenyl conmpounds. The resolution was made using normal-phase methodology with a mobile phase consisting of n-hexane-alcohol (ethanol, 1-propanol, 2-propanol or 1-butanol). The effects of various aliphatic alcohols in the mobile phase were studied. The structural features of the solutes that influence their k'were discussed. A dominant effect of trifluoroaetic acid on chiral separation of aacidicdic solutes was noted.

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

    OpenAIRE

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

    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 regard...

  6. Polychlorinated Biphenyls

    Science.gov (United States)

    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)

  7. Temporal trends of polychlorinated biphenyls, polybrominated diphenyl ethers, and perfluorinated compounds in Chinese sturgeon (Acipenser sinensis) eggs (1984-2008).

    Science.gov (United States)

    Jianxian, Sun; Hui, Peng; Jianying, Hu

    2015-02-03

    Because investigation on the temporal trends of persistent halogenated compounds (PHCs) is necessary to predict their future impacts on the environment and human health and evaluate the effectiveness of regulations on their production and usage, it is of concern to investigate annual temporal trends of PHCs in biota samples. This study examined the temporal trends of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and perfluorinated compounds (PFCs) in Chinese sturgeon (Acipenser sinensis) eggs over a period of 25 years (1984-2008), and 62 PCBs (19.2-1030 ng/g dw for total PCBs), 16 PBDEs (4.7-572 ng/g dw for total PBDEs), and 14 PFCs (26-46 ng/g dw for total PFCs) were detected. Although a decreasing temporal trend was observed for total PCBs with annual reduction rate of 3.4% (ρ = 0.005), a clear break point was observed around 1991, indicating their continuing emission in the 1980s in China. All major PBDEs showed increasing temporal trends, with annual change rates at 3.5-10.2% over the 25 years, but a sharp decreasing trend was observed after 2006, indicating a rapid response to the banning of PBDE usage in China in 2004. The greatest annual rate of increase was observed for BDE-28 (10.2%) followed by BDE-100 (7.7%), which would be due to metabolism input from higher brominated PBDEs. Significantly increasing temporal trends were observed for all PFCs, and the annual rates of increase were 7.9% and 5.9% for total perfluorinated carboxylic acids and perfluorooctanesulfonate (PFOS), respectively. A peak concentration for PFOS was observed in 1989, which may be related to the import history of PFCs in China. The present study is the first report of systematic temporal trends of PHCs in biota samples from China and shows that regulatory policy is needed to reduce their potential health and ecological risk in China considering the increasing temporal trends of PBDEs and PFCs.

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

    Directory of Open Access Journals (Sweden)

    Cornelia Chizzali

    Full Text Available 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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  11. Structural and electron charge density studies of a nonlinear optical compound 4,4 di-methyl amino cyano biphenyl

    Science.gov (United States)

    Naima, Boubegra; Abdelkader, Chouaih; Mokhtaria, Drissi; Fodil, Hamzaoui

    2014-01-01

    The 4,4 dimethyl amino cyano biphenyl crystal (DMACB) is characterized by its nonlinear activity. The intra molecular charge transfer of this molecule results mainly from the electronic transmission of the electro-acceptor (cyano) and electro-donor (di-methyl-amino) groups. An accurate electron density distribution around the molecule has been calculated based on a high-resolution X-ray diffraction study. The data were collected at 123 K using graphite-monochromated Mo K α radiation to sin(β)/λ = 1.24 Å-1. The integrated intensities of 13796 reflections were measured and reduced to 6501 independent reflections with I >= 3σ(I). The crystal structure was refined using the experimental model of Hansen and Coppens (1978). The crystal structure has been validated and deposited at the Cambridge Crystallographic Data Centre with the deposition number CCDC 876507. In this article, we present the thermal motion and the structural analysis obtained from the least-square refinement based on F2 and the electron density distribution obtained from the multipolar model.

  12. Occurrence and concentrations of selected trace elements and halogenated organic compounds in stream sediments and potential sources of polychlorinated biphenyls, Leon Creek, San Antonio, Texas, 2012–14

    Science.gov (United States)

    Wilson, Jennifer T.

    2016-06-23

    The Texas Department of State Health Services issued fish consumption advisories in 2003 and 2010 for Leon Creek in San Antonio, Texas, based on elevated concentrations of polychlorinated biphenyls (PCBs) in fish tissues. The U.S. Geological Survey (USGS) measured elevated PCB concentrations in stream-sediment samples collected during 2007–9 from Leon Creek at Lackland Air Force Base (now known as Joint Base San Antonio-Lackland; the sampling site at this base is hereinafter referred to as the “Joint Base site”) and sites on Leon Creek downstream from the base. This report describes the occurrence and concentrations of selected trace elements and halogenated organic compounds (pesticides, flame retardants, and PCBs) and potential sources of PCBs in stream-sediment samples collected from four sites on Leon Creek during 2012–14. In downstream order, sediment samples were collected from Leon Creek at northwest Interstate Highway 410 (Loop 410), Rodriguez Park, Morey Road, and Joint Base. The USGS periodically collected streambed-sediment samples during low flow and suspended-sediment samples during high flow.

  13. Phytoalexins of the Pyrinae: Biphenyls and dibenzofurans

    Directory of Open Access Journals (Sweden)

    Cornelia Chizzali

    2012-04-01

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

  14. Phytoalexins of the Pyrinae: Biphenyls and dibenzofurans.

    Science.gov (United States)

    Chizzali, Cornelia; Beerhues, Ludger

    2012-01-01

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

  15. Micrometeorological measurement of hexachlorobenzene and polychlorinated biphenyl compound air-water gas exchange in Lake Superior and comparison to model predictions

    Directory of Open Access Journals (Sweden)

    M. D. Rowe

    2012-01-01

    Full Text Available Air-water exchange fluxes of persistent, bioaccumulative and toxic (PBT substances are frequently estimated using the Whitman two-film (W2F method, but micrometeorological flux measurements of these compounds over water are rarely attempted. We measured air-water exchange fluxes of hexachlorobenzene (HCB and polychlorinated biphenyls (PCBs on 14 July 2006 in Lake Superior using the modified Bowen ratio (MBR method. Measured fluxes were compared to estimates using the W2F method, and to estimates from an Internal Boundary Layer Transport and Exchange (IBLTE model that implements the NOAA COARE bulk flux algorithm and gas transfer model. We reveal an inaccuracy in the estimate of water vapor transfer velocity that is commonly used with the W2F method for PBT flux estimation, and demonstrate the effect of use of an improved estimation method. Flux measurements were conducted at three stations with increasing fetch in offshore flow (15, 30, and 60 km in southeastern Lake Superior. This sampling strategy enabled comparison of measured and predicted flux, as well as modification in near-surface atmospheric concentration with fetch, using the IBLTE model. Fluxes estimated using the W2F model were compared to fluxes measured by MBR. In five of seven cases in which the MBR flux was significantly greater than zero, concentration increased with fetch at 1-m height, which is qualitatively consistent with the measured volatilization flux. As far as we are aware, these are the first reported micrometeorological air-water exchange flux measurements of PCBs.

  16. Micrometeorological measurement of hexachlorobenzene and polychlorinated biphenyl compound air-water gas exchange in Lake Superior and comparison to model predictions

    Directory of Open Access Journals (Sweden)

    M. D. Rowe

    2012-05-01

    Full Text Available Air-water exchange fluxes of persistent, bioaccumulative and toxic (PBT substances are frequently estimated using the Whitman two-film (W2F method, but micrometeorological flux measurements of these compounds over water are rarely attempted. We measured air-water exchange fluxes of hexachlorobenzene (HCB and polychlorinated biphenyls (PCBs on 14 July 2006 in Lake Superior using the modified Bowen ratio (MBR method. Measured fluxes were compared to estimates using the W2F method, and to estimates from an Internal Boundary Layer Transport and Exchange (IBLTE model that implements the NOAA COARE bulk flux algorithm and gas transfer model. We reveal an inaccuracy in the estimate of water vapor transfer velocity that is commonly used with the W2F method for PBT flux estimation, and demonstrate the effect of use of an improved estimation method. Flux measurements were conducted at three stations with increasing fetch in offshore flow (15, 30, and 60 km in southeastern Lake Superior. This sampling strategy enabled comparison of measured and predicted flux, as well as modification in near-surface atmospheric concentration with fetch, using the IBLTE model. Fluxes estimated using the W2F model were compared to fluxes measured by MBR. In five of seven cases in which the MBR flux was significantly greater than zero, concentration increased with fetch at 1-m height, which is qualitatively consistent with the measured volatilization flux. As far as we are aware, these are the first reported ship-based micrometeorological air-water exchange flux measurements of PCBs.

  17. Phytoalexins of the Pyrinae: Biphenyls and dibenzofurans

    OpenAIRE

    Cornelia Chizzali; Ludger Beerhues

    2012-01-01

    Biphenyls and dibenzofurans are the phytoalexins of the Pyrinae, a subtribe of the plant family Rosaceae. The Pyrinae correspond to the long-recognized Maloideae. Economically valuable species of the Pyrinae are apples and pears. Biphenyls and dibenzofurans are formed de novo in response to infection by bacterial and fungal pathogens. The inducible defense compounds were also produced in cell suspension cultures after treatment with biotic and abiotic elicitors. The antimicrobial activity of ...

  18. 40 CFR 129.105 - Polychlorinated biphenyls (PCBs).

    Science.gov (United States)

    2010-07-01

    ... produces polychlorinated biphenyls. (2) Electrical capacitor manufacturer means a manufacturer who produces or assembles electrical capacitors in which PCB or PCB-containing compounds are part of the... are prohibited in any discharge from any PCB manufacturer. (c) Electrical capacitor...

  19. Identification of isopropylbiphenyl, alkyl diphenylmethanes, diisopropylnaphthalene, linear alkyl benzenes and other polychlorinated biphenyl replacement compounds in effluents, sediments and fish in the Fox River System, Wisconsin

    Science.gov (United States)

    Peterman, Paul H.; Delfino, Joseph J.

    1990-01-01

    Five polychlorinated biphenyl replacement dye solvents and a diluent present in carbonless copy paper were identified by gas chromatography/mass spectrometry in the following matrices: effluents from a de-inking–recycling paper mill and a municipal wastewater treatment plant receiving wastewaters from a carbonless copy paper manufacturing plant; sediments; and fish collected near both discharges in the Fox River System, Wisconsin. An isopropylbiphenyl dye solvent mixture included mono-, di- and triisopropylbiphenyls. Also identified were two dye solvent mixtures marketed under the trade name Santosol. Santosol 100 comprised ethyl-diphenylmethanes (DPMs), benzyl-ethyl-DPMs, and dibenzyl-ethyl-DPMs. Similarly, Santosol 150 comprised dimethyl-DPMs, benzyl-dimethyl-DPMs, and dibenzyl-dimethyl-DPMs. Diisopropylnaphthalenes, widely used as a dye solvent in Japan, were identified for the first time in the US environment. sec-Butylbiphenyls and di-sec-butylbiphenyls, likely constituents of a sec-butylbiphenyl dye solvent mixture, were tentatively identified. Linear alkyl benzenes (C10 to C13-LABs) constituted the Alkylate 215 diluent mixture. Although known to occur as minor constituents in linear alkyl sulfonate detergents, LAB residues have not been previously attributed to commercial use of LABs.

  20. Determination of polydimethylsiloxane–water partition coefficients for ten 1-chloro-4-[2,2,2-trichloro-1-(4-chlorophenyl)ethyl]benzene-related compounds and twelve polychlorinated biphenyls using gas chromatography/mass spectrometry

    Science.gov (United States)

    Eganhouse, Robert P.

    2016-01-01

    Polymer-water partition coefficients (Kpw) of ten DDT-related compounds were determined in pure water at 25 °C using commercial polydimethylsiloxane-coated optical fiber. Analyte concentrations were measured by thermal desorption-gas chromatography/full scan mass spectrometry (TD–GC/MSFS; fibers) and liquid injection-gas chromatography/selected ion monitoring mass spectrometry (LI–GC/MSSIM; water). Equilibrium was approached from two directions (fiber uptake and depletion) as a means of assessing data concordance. Measured compound-specific log Kpw values ranged from 4.8 to 6.1 with an average difference in log Kpw between the two approaches of 0.05 log units (∼12% of Kpw). Comparison of the experimentally-determined log Kpw values with previously published data confirmed the consistency of the results and the reliability of the method. A second experiment was conducted with the same ten DDT-related compounds and twelve selected PCB (polychlorinated biphenyl) congeners under conditions characteristic of a coastal marine field site (viz., seawater, 11 °C) that is currently under investigation for DDT and PCB contamination. Equilibration at lower temperature and higher ionic strength resulted in an increase in log Kpw for the DDT-related compounds of 0.28–0.49 log units (61–101% of Kpw), depending on the analyte. The increase in Kpw would have the effect of reducing by approximately half the calculated freely dissolved pore-water concentrations (Cfree). This demonstrates the importance of determining partition coefficients under conditions as they exist in the field.

  1. 联苯型环氧液晶改性环氧塑封材料的性能研究%Study on the properties of biphenyl liquid crystalline epoxy modified epoxy molding compound

    Institute of Scientific and Technical Information of China (English)

    刘括; 陆绍荣; 黄斌; 罗崇禧; 郭栋

    2012-01-01

    合成了一种端环氧基的联苯型液晶(LCEP),采用红外光谱(FT-IR)、示差扫描量热法(DSC)和偏光显微镜(POM)对其结构和热性能进行了分析,并以LCEP、环氧树脂、无机粉体(Al2O3和AlN)制备了环氧塑封料,通过对其力学性能、导热系数、线膨胀系数、电性能及热稳定性的测试研究了LCEP及无机粉体的加入对塑封料性能的影响。结果表明:加入LCEP后,塑封材料的冲击性能、弯曲性能均有所提高。同时,塑封料的导热系数、介电常数、热分解温度随着Al2O3、AlN含量的增加而增大,LCEP对于提高材料的导热性和热稳定性也有一定贡献。而线膨胀系数、介电损耗随着Al2O3和AlN含量的增加而降低,加入LCEP后塑封料的线膨胀系数略有降低。%A epoxy terminated biphenyl-type liquid crystal(LCEP) was synthesized.Its structure and thermal properties were analyzed by using infrared spectroscopy(FT-IR),differential scanning calorimetry(DSC) and polarized light microscopy(POM).The epoxy molding compound was prepared by LCEP,epoxy resin and the inorganic powder(Al2O3 and AlN).The effect of the addition of LCEP and inorganic powder on the performance of the molding compound was studied by the testings of mechanical property,thermal conductivity,coefficient of linear expansion,electrical property and thermal stability.The results showed that: the impact properties and flexural properties were improved by the addition of LCEP.At the same time,the thermal conductivity,dielectric constant and thermal decomposition temperature of molding compound were increased with the increasing of Al2O3 and AlN content.The LCEP played a certain role in improving the thermal conductivity and thermal stability of the material.The linear expansion coefficient and dielectric loss were decreased with the increasing of Al2O3 and AlN content.The coefficient of linear expansion of the molding compound was

  2. Investigation of mechanisms of formation of biphenyls and benzonaphthothiophenes by simulation experiment

    Institute of Scientific and Technical Information of China (English)

    XIA; Yanqing(夏燕青); ZHANG; Gengxin(张更新)

    2002-01-01

    The formation mechanisms of biphenyl series and benzonaphthothiophene series are investigated by means of simulation experiment. Biphenyl series are likely formed in two ways: one is the aromatization of the chain compounds containing conjugated C== C double bonds or the compounds with such a kind of sidechains, and the other is the reaction of sulfur with ordinary chain compounds, in which sulphur acts on ordinary sidechain compounds by seizing some hydrogens and forming (H2S and) the intermediates with conjugated C== C double bonds first, and then the intermediates are aromatized. One of the basic precursors of benzonaphthothiophenes is likely the phenylnaphthalenes which may originate from the chain compounds containing conjugated C== C double bonds, the compounds with such sidechains and saturate or unsaturate chain compounds. Thermal stability of biphenyls is high, but they can become dibenzothiophenes and polycyclic aromatic hydrocarbons or dibenzofurans and polycyclic aromatic hydrocarbons respectively in the presence of sulphur or oxygen. The ratio of biphenyl and m-biphenyl to biphenyls may be employed to indicate the depositional environment in the mild to medium maturation, of which the higher value indicates a fresh water depositional environment and the lower indicates a saline depositional environment. The relative high content of benzonaphthothiophenes in the crude oil indicates that the crude oil has undergone an intense sulfurization in the source rock or reservoir.

  3. Polychlorinated Biphenyls: In situ Bioremediation from the Environment

    Science.gov (United States)

    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...

  4. Synthesis of P,N-2,2’-biphenyl derivatives with central chirality

    Institute of Scientific and Technical Information of China (English)

    JEAN; Ludovic; POULIQUEN; Michael; BLANCHET; Jér?me; LASNE; Marie-Claire; ROUDEN; Jacques

    2010-01-01

    Enantiopure 2-(dicyclohexylphosphino)-1,1’-biphenyl derivatives substituted in the 2’-position by a chiral amino group were prepared.For the compound bearing an acyclic chiral chain,the key step was a Suzuki coupling between bromobenzeneboronic acid and N-Boc-iodoaniline whereas an aromatic nucleophilic substitution allowed the introduction of a chiral pyrrolidine in the 2’-position of the biphenyl backbone.The efficiency of the P,N-biphenyl pyrrolidine derivatives as ligands in Pd-catalyzed arylaminations compares well with that of DavePhos ligand.

  5. Biphenyl Phytoalexin in Sorbus pohuashanensis Suspension Cell Induced by Yeast Extract

    OpenAIRE

    Liangyun Zhou; Jian Yang; Guang Yang; Chuanzhi Kang; Wenjuan Xiao; Chaogeng Lv; Sheng Wang; Jinfu Tang; Lanping Guo

    2016-01-01

    Biphenyls are unique phytoalexins de novo synthesized in plants in response to pathogen attack. These compounds are found in Maloideae, a subfamily of the Rosaceae. The anti-microbial activities of biphenyls have been reported in a number of studies and they appear to represent an important defense strategy against pathogens common in the Maloideae, such as species in Malus, Pyrus, Sorbus, and Chaenomeles. Here, cell suspension cultures of Sorbus pohuashanensis were established to study biphe...

  6. Aerobic degradation of polychlorinated biphenyls

    Energy Technology Data Exchange (ETDEWEB)

    Pieper, D.H. [Dept. of Environmental Microbiology, German Research Center for Biotechnology, Braunschweig (Germany)

    2005-04-01

    The microbial degradation of polychlorinated biphenyls (PCBs) has been extensively studied in recent years. The genetic organization of biphenyl catabolic genes has been elucidated in various groups of microorganisms, their structures have been analyzed with respect to their evolutionary relationships, and new information on mobile elements has become available. Key enzymes, specifically biphenyl 2,3-dioxygenases, have been intensively characterized, structure/sequence relationships have been determined and enzymes optimized for PCB transformation. However, due to the complex metabolic network responsible for PCB degradation, optimizing degradation by single bacterial species is necessarily limited. As PCBs are usually not mineralized by biphenyl-degrading organisms, and cometabolism can result in the formation of toxic metabolites, the degradation of chlorobenzoates has received special attention. A broad set of bacterial strategies to degrade chlorobenzoates has recently been elucidated, including new pathways for the degradation of chlorocatechols as central intermediates of various chloroaromatic catabolic pathways. To optimize PCB degradation in the environment beyond these metabolic limitations, enhancing degradation in the rhizosphere has been suggested, in addition to the application of surfactants to overcome bioavailability barriers. However, further research is necessary to understand the complex interactions between soil/sediment, pollutant, surfactant and microorganisms in different environments. (orig.)

  7. An efficient synthesis, X-ray and spectral characterization of biphenyl derivatives

    Indian Academy of Sciences (India)

    Ravindra R Kamble; Dharesh B Biradar; Gangadhar Y Meti; Tasneem Taj; Tegginamath Gireesh; Imthiyaz Ahmed M Khazi; Sundar T Vaidyanathan; Raju Mohandoss; Balasubramanian Sridhar; Viraraghav Parthasarathi

    2011-07-01

    Derivatives of 1,3-thiazolidin-2,4-dione appended to biphenyl ring viz., 7-9, 16-18 were prepared. The newly synthesized compounds were confirmed by IR, NMR (1H and 13C) MS and elemental analyses. Single crystal X-ray diffraction study was carried out for one of the final compounds 9.

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

    Science.gov (United States)

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

    2017-01-01

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

  9. 21 CFR 109.30 - Tolerances for polychlorinated biphenyls (PCB's).

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Tolerances for polychlorinated biphenyls (PCB's... Tolerances for polychlorinated biphenyls (PCB's). (a) Polychlorinated biphenyls (PCB's) are toxic, industrial... practicable time. For the purposes of this paragraph, the term “polychlorinated biphenyls (PCB's)”...

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

    Science.gov (United States)

    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...

  11. EFFECTS OF POLYCHLORINATED-BIPHENYLS (PCBS) AND DIOXINS ON GROWTH AND DEVELOPMENT

    NARCIS (Netherlands)

    SAUER, PJJ; HUISMAN, M; KOOPMANESSEBOOM, C; MORSE, DC; SMITSVANPROOIJE, AE; VANDEBERG, KJ; TUINSTRA, LGMT; VANDERPAAUW, CG; BOERSMA, ER; WEISGLASKUPERUS, N; LAMMERS, JHCM; KULIG, BM; BROUWER, A

    1994-01-01

    Polychlorinated biphenyls (PCBs) and dioxins are potentially toxic compounds which occur widely in the environment. Their effects on the growth and development of infants at the levels currently found in highly industrialised western countries is not well known. This Dutch multicenter study, combini

  12. Synthesis and properties of a new diarylethene having thiazole and biphenyl moieties

    Energy Technology Data Exchange (ETDEWEB)

    Li Hui; Pu Shouzhi; Liu Gang; Liu Weijun, E-mail: pushouzhi@tsinghua.org.cn [Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science and Technology Normal University, Nanchang 330013 (China)

    2011-02-01

    A novel photochromic diarylethene bearing thiazole and biphenyl moieties has been synthesized. Its properties, including photochromism and fluorescence were investigated in detail. It underwent reversible cyclization and cycloreversion reactions upon alternating irradiation with UV and visible light in hexane. The results showed that this compound exhibited reversible photochromism and good fluorescent switching in solution after irradiation with UV light and visible light.

  13. Prediction of the Aqueous Solubilities of Polychlorinated Biphenyls

    Institute of Scientific and Technical Information of China (English)

    Shu Shen LIU; Shi Hai CUI; Lian Sheng WANG

    2004-01-01

    Using the molecular electronegativity distance vector descriptors derived directly from the molecular topological structures, the aqueous solubilities of polychlorinated biphenyls(PCBs)were predicted. A three-variable regression equation with correlation coefficient of 0.9739 and the root mean square errors of 0.26 was developed. The descriptors included in the equation represent three interactions between three pairs of atomic types,I.e.,atom-C=and>C=,-C=and-Cl,and-Cland-Cl.It has been proved that the aqueous solubilities of 137 PCB congeners can be accurately predicted as long as there are more than 65 calibration compounds.

  14. Structures of cyano-biphenyl liquid crystals

    Science.gov (United States)

    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.

  15. Can Stress Enhance Phytoremediation of Polychlorinated Biphenyls?

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  18. Synthesis and Characterization of Nonsymmetric Liquid Crystal Dimer Containing Biphenyl and Azobenzene Moiety

    Directory of Open Access Journals (Sweden)

    S. Sandy Subala

    2013-01-01

    Full Text Available Calamitic liquid crystalline dimer containing azobenzene moiety and a decyloxy biphenyl linked by flexible spacers {4-[7-(4′-decyloxy-biphenyl-4-yloxy-alkyloxy]-phenyl}-(4-decyl-phenyl-diazene has been synthesized and characterized by spectroscopic methods. The transition temperatures and phase behaviours were studied by Differential Scanning Calorimeter (DSC and Polarizing Optical Microscope (POM. The synthesized compounds exhibited enantiotropic liquid crystal phase with higher spacer display nematic and smectic C phases while lower spacer shows nematic and smectic A phases.

  19. Molecular Descriptors Family on Structure Activity Relationships 6. Octanol-Water Partition Coefficient of Polychlorinated Biphenyls

    Directory of Open Access Journals (Sweden)

    Lorentz JÄNTSCHI

    2006-01-01

    Full Text Available Octanol-water partition coefficient of two hundred and six polychlorinated biphenyls was model by the use of an original method based on complex information obtained from compounds structure. The regression analysis shows that best results are obtained in four-varied model (r2 = 0.9168. The prediction ability of the model was studied through leave-one-out analysis (r2cv(loo = 0.9093 and in training and test sets analysis. Modeling the octanol-water partition coefficient of polychlorinated biphenyls by integration of complex structural information provide a stable and performing four-varied model, allowing us to make remarks about relationship between structure of polychlorinated biphenyls and associated octanol-water partition coefficients.

  20. 2,2,6,6-Tetrakis(biphenyl-2-yl-4,4,8,8-tetramethylcyclotetrasiloxane

    Directory of Open Access Journals (Sweden)

    Erik P. A. Couzijn

    2009-09-01

    Full Text Available The title compound, [–Si(C12H92OSi(CH32O–]2, was obtained unintentionally as the product of an attempted crystallization of caesium bis(biphenyl-2,2′-diylfluorosilicate from dimethylformamide. In the crystal, the molecule is located on an inversion center and the siloxane ring adopts a twist-chair conformation with the two dimethyl-substituted Si atoms lying 0.7081 (5 Å out of the plane defined by the two bis(biphenyl-2-yl-substituted Si atoms and the four O atoms. In each Si(C12H92 unit, the orientation of one terminal phenyl ring relative to the phenylene ring of the other biphenyl moiety suggests a parallel displaced π–π stacking interaction [centroid distance = 4.2377 (11 Å and dihedral angle = 15.40 (9°].

  1. Design, synthesis, pharmacological evaluation and computational studies of 1-(biphenyl-4-yl)-2-[4-(substituted phenyl)-piperazin-1-yl]ethanones as potential antipsychotics.

    Science.gov (United States)

    Bhosale, Sharad H; Kanhed, Ashish M; Dash, Radha Charan; Suryawanshi, Mugdha R; Mahadik, K R

    2014-03-03

    This article describes the design of biphenyl moiety linked with aryl piperazine and syntheses of fourteen 1-(biphenyl-4-yl)-2-[4-(substituted phenyl)-piperazin-1-yl]ethanone derivatives along with their pharmacological evaluation for antipsychotic activity and computational studies including quantitative structure activity relationship (QSAR) and descriptor based similarity study. All compounds were found to exhibit considerable anti-dopaminergic and anti-serotonergic activity in behavioural models. Among all derivatives, compound 1-(biphenyl-4-yl)-2-[4-(2-methoxyphenyl)-piperazin-1-yl]ethanone (3c) and 1-(biphenyl-4-yl)-2-[4-(2,3-dichlorophenyl)-piperazin-1-yl]ethanone (3k) showed impressive antipsychotic profile with lower potency for catalepsy induction. These results were found to be sturdily matching with docking study in designing of compounds with homology model of human dopamine D2 receptor. Also the QSAR study strongly supports the obtained results.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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...

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

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Polychlorinated biphenyls... Hazardous Materials and Certain Categories of Property § 101-42.1102-2 Polychlorinated biphenyls. (a) General. (1) Polychlorinated biphenyls (PCBs) are one member of a class of chlorinated aromatic...

  5. Synthesis of new biphenyl-substituted quinoline derivatives, preliminary screening and docking studies

    Indian Academy of Sciences (India)

    Nellisara D Shashikumar; Ganganaika Krishnamurthy; Halehatti S Bhojyanaik; Mayasandra R Lokesh; Kaginalli S Jithendrakumara

    2014-01-01

    New quinoline derivatives containing biphenyl ring were synthesized and characterized by IR, 1H NMR and mass spectral studies. The synthesized compounds were screened for antimicrobial, anthelmintic activities as well as free radical scavenging property against the DPPH radical. The minimum inhibition concentration values showed promising inhibiting activity and are potent biological agents. The compounds showed minimum binding energy towards -tubulin. The compounds 11a, 11c, 13c and 13d have good affinity towards the active pocket and may be considered as a good inhibitor of -tubulin.

  6. Synthesis and biological evaluation of nitric oxide-releasing sixalkoxyl biphenyl derivatives as anticancer agents

    Institute of Scientific and Technical Information of China (English)

    Xiang Wen Kong; Yi Hua Zhang; Li Dai; Hui Ji; Yi Sheng Lai; Si Xun Peng

    2008-01-01

    A series of novel nitric oxide-donating sixalkoxyl biphenyl derivatives (14a-i)were synthesized by coupling furoxan with alkoxyl biphenyl skeleton using amino acids as the spacers,and their cytotoxicity against HepG2 cells in vitro were evaluated by MTr method.It was found that 14c,14d,14f,14i,14j and 14k showed more potent cytotoxic activities than control 5-fluorouracil.NO release assay of target compounds indicated that the maximum amount of NO released by most active compounds 14c and 14j was about 6 x 10-2μmol/L,whereas 14a and 14h with very weak activity only released NO of 1 x 10-μmol/L.

  7. Human biological monitoring of suspected endocrine-disrupting compounds

    OpenAIRE

    Moosa Faniband; Lindh, Christian H; Bo AG Jönsson

    2014-01-01

    Endocrine-disrupting compounds are exogenous agents that interfere with the natural hormones of the body. Human biological monitoring is a powerful method for monitoring exposure to endocrine disrupting compounds. In this review, we describe human biological monitoring systems for different groups of endocrine disrupting compounds, polychlorinated biphenyls, brominated flame retardants, phthalates, alkylphenols, pesticides, metals, perfluronated compounds, parabens, ultraviolet filters, and o...

  8. Biphenyl Phytoalexin in Sorbus pohuashanensis Suspension Cell Induced by Yeast Extract.

    Science.gov (United States)

    Zhou, Liangyun; Yang, Jian; Yang, Guang; Kang, Chuanzhi; Xiao, Wenjuan; Lv, Chaogeng; Wang, Sheng; Tang, Jinfu; Guo, Lanping

    2016-09-14

    Biphenyls are unique phytoalexins de novo synthesized in plants in response to pathogen attack. These compounds are found in Maloideae, a subfamily of the Rosaceae. The anti-microbial activities of biphenyls have been reported in a number of studies and they appear to represent an important defense strategy against pathogens common in the Maloideae, such as species in Malus, Pyrus, Sorbus, and Chaenomeles. Here, cell suspension cultures of Sorbus pohuashanensis were established to study biphenyl phytoalexins formation after yeast extract (YE) treatment. An ultra-performance liquid chromatography (UPLC) method coupled with quadrupole time of flight mass spectrometry (Q-TOF-MS) LC-MS/MS was applied to determine the time course of these biphenyl biomarkers accumulation in YE-treated S. pohuashanensis suspension cells. The results of quantitative analyses show the content of Noraucuparin, 2'-Hydroxyaucuparin, and their glycosides initially increased, then decreased over time. The Noraucuparin content reached its highest (225.76 μg·g(-1)) at 18 h after treatment, 6 hours earlier than that of Noraucuparin 5-O-β-d-glucopyranoside. The content of 2'-Hydroxyaucuparin reached its highest (422.75 μg·g(-1)) at 30 h after treatment, also earlier than that of its glycoside. The understanding of phytoalexin metabolism in this study may provide a basis for improving Maloideae resistance to pathogens.

  9. Biphenyl Phytoalexin in Sorbus pohuashanensis Suspension Cell Induced by Yeast Extract

    Directory of Open Access Journals (Sweden)

    Liangyun Zhou

    2016-09-01

    Full Text Available Biphenyls are unique phytoalexins de novo synthesized in plants in response to pathogen attack. These compounds are found in Maloideae, a subfamily of the Rosaceae. The anti-microbial activities of biphenyls have been reported in a number of studies and they appear to represent an important defense strategy against pathogens common in the Maloideae, such as species in Malus, Pyrus, Sorbus, and Chaenomeles. Here, cell suspension cultures of Sorbus pohuashanensis were established to study biphenyl phytoalexins formation after yeast extract (YE treatment. An ultra-performance liquid chromatography (UPLC method coupled with quadrupole time of flight mass spectrometry (Q-TOF-MS LC−MS/MS was applied to determine the time course of these biphenyl biomarkers accumulation in YE-treated S. pohuashanensis suspension cells. The results of quantitative analyses show the content of Noraucuparin, 2′-Hydroxyaucuparin, and their glycosides initially increased, then decreased over time. The Noraucuparin content reached its highest (225.76 μg·g−1 at 18 h after treatment, 6 hours earlier than that of Noraucuparin 5-O-β-d-glucopyranoside. The content of 2′-Hydroxyaucuparin reached its highest (422.75 μg·g−1 at 30 h after treatment, also earlier than that of its glycoside. The understanding of phytoalexin metabolism in this study may provide a basis for improving Maloideae resistance to pathogens.

  10. Alkoxyresorufin-O-deethylase activities and polychlorinated biphenyl patterns in shrews as biomarkers in environmental risk assessments: sensitivity and specificity

    NARCIS (Netherlands)

    Brink, van den N.W.; Bosveld, A.T.C.

    2005-01-01

    Alkoxyresorufin-O-deethylase (AROD) biomarkers are useful indicators of the exposure of organisms to dioxin-like compounds. In the current study, an in vivo validation of the use of such biomarkers in shrews was conducted. Furthermore, the use of changes in polychlorinated biphenyl (PCB) patterns as

  11. Determination of in vitro relative potency (REP) values for mono-ortho polychlorinated biphenyls after purification with active charcoal

    NARCIS (Netherlands)

    Peters, A.K.; Leonards, P.E.G.; Zhao, B.; Bergman, A.; Denison, M.S.; Berg, van den M.

    2006-01-01

    The TEF system for dioxin-like compounds has included assignment of TEF values for mono-ortho polychlorinated biphenyls (MO-PCBs). Small traces of aryl hydrocarbon receptor (AhR)-active impurities could result in artifactually higher relative potency (REP) values. MO-PCBs -105, -118, -156, and -167

  12. Polychlorinated biphenyls fractioning assessment in aqueous bioremediation assy with phanerochaete chrysosporium

    OpenAIRE

    2009-01-01

    Thanks to growing environmental concerns in public opinion, bioremediation processes are more and more used to decontaminate soils from organic compounds. Polychlorinated biphenyls (PCBs) are known to be world wide spread persistent organic pollutants (POPs). The white rot fungus Phanerochaete chrysosporium is able to degrade PCBs in water, and soil As POPs, PCBs can also be adsorbed onto organic matter, such as Phanerochaete chrysosporium mycelium. This study aims at estimating the fractioni...

  13. Updated Abraham solvation parameters for polychlorinated biphenyls

    NARCIS (Netherlands)

    van Noort, P.C.M.; Haftka, J.J.H.; Parsons, J.R.

    2010-01-01

    This study shows that the recently published polychlorinated biphenyl (PCB) Abraham solvation parameters predict PCB air−n-hexadecane and n-octanol−water partition coefficients very poorly, especially for highly ortho-chlorinated congeners. Therefore, an updated set of PCB solvation parameters was d

  14. Separation and enrichment of six indicator polychlorinated biphenyls from real waters using a novel magnetic multiwalled carbon nanotube composite absorbent.

    Science.gov (United States)

    Zhang, Jiabin; Gan, Ning; Pan, Muyun; Lin, Saichai; Cao, Yuting; Wu, Dazhen; Long, Nengbing

    2015-03-01

    A novel and effective magnetic multiwalled carbon nanotube composite for the separation and enrichment of polychlorinated biphenyls was developed. Fe3 O4 @SiO2 core-shell structured nanoparticles were first synthesized, then the poly(sodium 4-styrenesulfonate) was laid on its surface to prepare the polyanionic magnetic nanoparticles. The above materials were then grafted with polycationic multiwalled carbon nanotubes, which were modified by polydiallyl dimethyl ammonium chloride through the layer-by-layer self-assembly approach. Its performance was tested by magnetic solid-phase extraction and gas chromatography with mass spectrometry for the determination of six kinds of indicator polychlorinated biphenyls in water samples. Under optimal conditions, the spiked recoveries of several real samples for six kinds of polychlorinated biphenyls (PCB28, PCB52, PCB101, PCB138, PCB153, PCB180) were in the range of 73.4-99.5% with relative standard deviations varying from 1.5 to 8.4%. All target compounds showed good linearities in the tested range with correlation coefficients higher than 0.9993. The limits of quantification for six kinds of indicator polychlorinated biphenyls were between 0.018 and 0.039 ng/mL. The proposed method was successfully applied to analyze polychlorinated biphenyls in real water samples. Satisfactory results were obtained using the effective magnetic absorbent.

  15. Electronic and thermal properties of Biphenyl molecules

    Science.gov (United States)

    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.

  16. Molecular Transistor Based on the Biphenyl Substituents

    Directory of Open Access Journals (Sweden)

    A.G. Malashenko

    2016-11-01

    Full Text Available It was investigated the physical processes in the molecules, which have properties required in case of using as molecular switches, transistors, or other electronic elements of future computers. Studies show that in the molecules of biphenyl substituents the angle between the planes of the phenyl rings depends on the magnitude of the applied external electric field. So, the ratio of squares of cosines of the angles between the phenyl groups in the field 0.01 a.u. and without field reaches 18. It significantly changes the ability of electrons to move along the long axis of the molecule. By varying the nature of the substituents, we can obtain the molecule characteristics that make these molecules promising for future using. This effect provides the use of biphenyl substitutes as transistors in electrical circuits constructed on separate molecules.

  17. Toxicity mechanisms and interactions of polychlorinated biphenyls and polybrominated diphenylethers

    Directory of Open Access Journals (Sweden)

    Antonijević Biljana

    2012-01-01

    Full Text Available Polychlorinated biphenyls (PCBs and brominated flame retardants, polybrominated diphenylethers (PBDEs, are widespread environmental contaminants as a result of anthropogenic activities and due to their persistency and resistance to degradation. Both groups of chemicals are placed on the list of persistent organic pollutants (POPs, covered by the Stockholm convention which is aimed to limit or ban the production, use, emission, import and export of POPs in order to protect human health and the environment. Taking into account the structural similarity between PCBs and PBDEs, and the known effects of PCBs, these two groups of chemicals could have similar mechanisms of action. Also, because of real simultaneous exposure to these compounds, an examination of possible interactions is of great importance. Interactions of the compounds from these groups are likely at the system level of hormones, particularly thyroid and reproductive ones. As there are mechanisms of adverse effects of both groups of chemicals on the nervous system, including functional, neurological and behavioral changes, there are influences on neurotransmiters, changes in signal transduction and apoptosis. There are interactions affecting the occurrence of metabolic disorders as well. Data on the toxicity of mixtures of PCBs and PBDEs, as well as interactions of these chemicals would contribute to the processes of risk evaluation and risk characterisation. [Projekat Ministarstva nauke Republike Srbije, br. III 46009

  18. Metabolism and metabolites of polychlorinated biphenyls.

    Science.gov (United States)

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

    2015-03-01

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

  19. Dioxins, furans, and polychlorinated biphenyls in hen eggs – a new source of hazard for consumers?

    Directory of Open Access Journals (Sweden)

    Piskorska-Pliszczyńska Jadwiga

    2015-12-01

    Full Text Available The paper presents the results of testing eggs for the content of dioxins and polychlorinated biphenyls (PCBs, determination of the sources that caused the presence of high concentrations of these compounds which exceeded the acceptable contamination levels, and assessment of consumer health risk caused by the consumption of eggs with excessive contents of investigated compounds. In about 9% of free range eggs and 17% of organic eggs, the content of PCDD/Fs was two- or threefold higher than the acceptable limits, and in some samples the concentration of investigated compounds exceeded the maximum concentration levels. Based on the profile of the compounds, it was confirmed in several cases that their main source was the soil or unsecured refuse. The consumers of eggs and meat produced under these conditions constitute the risk groups, and their dioxin and PCB intake may exceed toxicological reference values.

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

    Science.gov (United States)

    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.

  1. Biphenyl 4-Hydroxylases Involved in Aucuparin Biosynthesis in Rowan and Apple Are Cytochrome P450 736A Proteins1[OPEN

    Science.gov (United States)

    Kaufholdt, David; Broggini, Giovanni A.L.; Flachowsky, Henryk; Hänsch, Robert

    2015-01-01

    Upon pathogen attack, fruit trees such as apple (Malus spp.) and pear (Pyrus spp.) accumulate biphenyl and dibenzofuran phytoalexins, with aucuparin as a major biphenyl compound. 4-Hydroxylation of the biphenyl scaffold, formed by biphenyl synthase (BIS), is catalyzed by a cytochrome P450 (CYP). The biphenyl 4-hydroxylase (B4H) coding sequence of rowan (Sorbus aucuparia) was isolated and functionally expressed in yeast (Saccharomyces cerevisiae). SaB4H was named CYP736A107. No catalytic function of CYP736 was known previously. SaB4H exhibited absolute specificity for 3-hydroxy-5-methoxybiphenyl. In rowan cell cultures treated with elicitor from the scab fungus, transient increases in the SaB4H, SaBIS, and phenylalanine ammonia lyase transcript levels preceded phytoalexin accumulation. Transient expression of a carboxyl-terminal reporter gene construct directed SaB4H to the endoplasmic reticulum. A construct lacking the amino-terminal leader and transmembrane domain caused cytoplasmic localization. Functional B4H coding sequences were also isolated from two apple (Malus × domestica) cultivars. The MdB4Hs were named CYP736A163. When stems of cv Golden Delicious were infected with the fire blight bacterium, highest MdB4H transcript levels were observed in the transition zone. In a phylogenetic tree, the three B4Hs were closest to coniferaldehyde 5-hydroxylases involved in lignin biosynthesis, suggesting a common ancestor. Coniferaldehyde and related compounds were not converted by SaB4H. PMID:25862456

  2. Changes in patterns of persistent halogenated compounds through a pelagic food web in the Baltic Sea

    DEFF Research Database (Denmark)

    Stephansen, Diana Agnete; Svendsen, Tore Christian; Vorkamp, Katrin

    2012-01-01

    The concentrations and patterns of persistent halogenated compounds (PHCs), including polychlorinated biphenyls (PCBs), DDT, hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB) and polybrominated diphenyl ethers (PBDEs) were examined in a pelagic food web from the southern Baltic Sea consisting...

  3. [Exposure to polychlorinated biphenyls (PCBs) in food and cancer risk: recent advances].

    Science.gov (United States)

    Roveda, Anna Maria; Veronesi, Licia; Zoni, Roberta; Colucci, Maria Eugenia; Sansebastiano, Giuliano

    2006-01-01

    Polychlorinated Biphenyls are synthetic chlorinated hydrocarbon compounds whose commercial production started in the thirties and that have been widely used in the electro-technical industry. Although their production was stopped over 25 years ago, the Stockholm Convention included these compounds among the list of Persistent Organic Pollutants (POPs). In fact, humans continue to be exposed to the toxic effects of PCBs because of their resistance to chemical and biological decomposition, their capacity of bio-accumulation and their long half-life. Studies performed so far have pointed out a possible association between exposure to Polychlorinated Biphenyls and increased risk of developing some types of cancer (breast, prostate, testicular, ovarian and uterine cancers); it has also been suggested that these compounds may act as disruptive endocrine and cause infertility as well as other hormone-regulated disorders. PCBs accumulate in organisms through the food chain, and food is therefore the main exposure source for humans: it accounts for over 90% of exposure, the highest concentrations being found in fish (such as salmon and shellfish), dairy products (especially milk and butter) and animal fat. Moreover, waste-heaps, illegal disposal of oil waste and combustion of certain waste products in incineration plants represent sources of environmental pollution. The highest levels of PCBs in the environment were found in the early 1970s; since then concentrations of Polychlorinated Biphenyls have gradually decreased in all environmental components (water, air, earth and sediments), in fish, in other food products and lastly also in humans, thus suggesting that the associated risks have also likewise diminished.

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

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Temporary tolerances for polychlorinated biphenyls....30 Temporary tolerances for polychlorinated biphenyls (PCB's). (a) Polychlorinated biphenyls (PCB's.... (b) A compilation entitled “Analytical Methodology for Polychlorinated Biphenyls, February 1973”...

  5. trans-Tetraaquabis(nicotinamide-κNcadmium(II biphenyl-4,4′-disulfonate

    Directory of Open Access Journals (Sweden)

    Changlun Shao

    2008-02-01

    Full Text Available In the title compound, [Cd(C6H6N2O2(H2O4](C10H8O6S2, the CdII ion is located on a crystallographic inversion centre. An octahedral coordination geometry is defined by four water molecules in one plane, and two trans N-atom donors of the nicotinamide ligands. The biphenyl-4,4′-disulfonate anion also lies on a crystallographic inversion centre. In the crystal structure, the complex cations are connected to the counter-anions via N—H...O and O—H...O hydrogen bonds, forming a three-dimensional network.

  6. Kinetics of polychlorinated biphenyl partitioning to marine Chrysophyte Isochrysis galbana

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Fung-Chi, E-mail: ko@nmmba.gov.tw [National Dong Hwa University, Institute of Marine Biodiversity and Evolutionary Biology, Taiwan, ROC (China); National Museum of Marine Biology and Aquarium, Pingtung, Taiwan, ROC (China); Baker, Joel E. [The Center for Urban Waters, University of Washington, Tacoma, WA 98402 (United States); Tew, Kwee S. [National Dong Hwa University, Institute of Marine Biodiversity and Evolutionary Biology, Taiwan, ROC (China); National Museum of Marine Biology and Aquarium, Pingtung, Taiwan, ROC (China)

    2012-02-01

    This study focused on the uptake kinetics of polychlorinated biphenyl (PCB) congeners by the Chrysophyte, Isochrysis galbana. A gas-purging experimental system was used to maintain constant dissolved PCB concentrations. Three phases of absorption were observed: first, a rapid absorption phase within the first 15 min, second, a first order process reaching the maximum concentration within 48 h of exposure, and third, a plateau phase as yet to be determined with very slight increases in concentration. In this study, the percentage of the maximum concentration reached within the first phase varied from 10% to 67%, depending on the size of the PCB (as determined by molecular weight and total surface area), whereas the uptake rate (k{sub u}) during the second phase was more comparable across different PCBs. In addition, for the first phase, the bioconcentration factor (BCF) of PCBs deviated from its expected relationship with hydrophobicity, as determined by K{sub ow}, and was instead related to the molecular structure of the compound.

  7. Kinetics of polychlorinated biphenyl partitioning to marine Chrysophyte Isochrysis galbana.

    Science.gov (United States)

    Ko, Fung-Chi; Baker, Joel E; Tew, Kwee S

    2012-02-01

    This study focused on the uptake kinetics of polychlorinated biphenyl (PCB) congeners by the Chrysophyte, Isochrysis galbana. A gas-purging experimental system was used to maintain constant dissolved PCB concentrations. Three phases of absorption were observed: first, a rapid absorption phase within the first 15min, second, a first order process reaching the maximum concentration within 48h of exposure, and third, a plateau phase as yet to be determined with very slight increases in concentration. In this study, the percentage of the maximum concentration reached within the first phase varied from 10% to 67%, depending on the size of the PCB (as determined by molecular weight and total surface area), whereas the uptake rate (k(u)) during the second phase was more comparable across different PCBs. In addition, for the first phase, the bioconcentration factor (BCF) of PCBs deviated from its expected relationship with hydrophobicity, as determined by K(ow), and was instead related to the molecular structure of the compound.

  8. Accumulation and efflux of polychlorinated biphenyls in Escherichia coli.

    Science.gov (United States)

    Geng, Shen; Fang, Jun; Turner, Kendrick B; Daunert, Sylvia; Wei, Yinan

    2012-06-01

    Polychlorinated biphenyls (PCBs) are environmental pollutants that have been associated with numerous adverse health effects in human and animals. Hydroxylated PCBs (HPCBs) are the product of the oxidative metabolism of PCBs. The presence of hydroxyl groups in HPCBs makes these compounds more hydrophilic than the parent PCBs. One of the best approaches to break down and remove these contaminants is bioremediation; an environmentally friendly process that uses microorganisms to degrade hazardous chemicals into non-toxic ones. In this study, we investigated the cellular accumulation and toxicity of selected PCBs and HPCBs in Gram-negative bacteria, using Escherichia coli as a model organism. We found that none of the five PCBs tested were toxic to E. coli, presumably due to their limited bioavailability. Nevertheless, different HPCBs tested showed different levels of toxicity. Furthermore, we demonstrated that the primary multidrug efflux system in E. coli, AcrAB-TolC, facilitated the efflux of HPCBs out of the cell. Since AcrAB-TolC is constitutively expressed in E. coli and is conserved in all sequenced Gram-negative bacterial genomes, our results suggest that the efflux activities of multidrug resistant pumps may affect the accumulation and degradation of PCBs in Gram-negative bacteria.

  9. Polychlorinated biphenyls and their interaction with the environment

    Energy Technology Data Exchange (ETDEWEB)

    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.

  10. Sphingobium fuliginis HC3: a novel and robust isolated biphenyl- and polychlorinated biphenyls-degrading bacterium without dead-end intermediates accumulation.

    Directory of Open Access Journals (Sweden)

    Jinxing Hu

    Full Text Available 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.

  11. Human biological monitoring of suspected endocrine-disrupting compounds.

    Science.gov (United States)

    Faniband, Moosa; Lindh, Christian H; Jönsson, Bo A G

    2014-01-01

    Endocrine-disrupting compounds are exogenous agents that interfere with the natural hormones of the body. Human biological monitoring is a powerful method for monitoring exposure to endocrine disrupting compounds. In this review, we describe human biological monitoring systems for different groups of endocrine disrupting compounds, polychlorinated biphenyls, brominated flame retardants, phthalates, alkylphenols, pesticides, metals, perfluronated compounds, parabens, ultraviolet filters, and organic solvents. The aspects discussed are origin to exposure, metabolism, matrices to analyse, analytical determination methods, determinants, and time trends.

  12. Bioaccumulation dynamics of polychlorinated biphenyls (PCBs) and organochlorine pesticides

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bioaccumulation dynamics of polychlorinated biphenyls (PCBs) and organochlorine pesticides was examined in young-of-the-year bluefish from seven sub-estuaries of New...

  13. Tetraanionic biphenyl lanthanide complexes as single-molecule magnets.

    Science.gov (United States)

    Huang, Wenliang; Le Roy, Jennifer J; Khan, Saeed I; Ungur, Liviu; Murugesu, Muralee; Diaconescu, Paula L

    2015-03-02

    Inverse sandwich biphenyl complexes [(NN(TBS))Ln]2(μ-biphenyl)[K(solvent)]2 [NN(TBS) = 1,1'-fc(NSi(t)BuMe2)2; Ln = Gd, Dy, Er; solvent = Et2O, toluene; 18-crown-6], containing a quadruply reduced biphenyl ligand, were synthesized and their magnetic properties measured. One of the dysprosium biphenyl complexes was found to exhibit antiferromagnetic coupling and single-molecule-magnet behavior with Ueff of 34 K under zero applied field. The solvent coordinated to potassium affected drastically the nature of the magnetic interaction, with the other dysprosium complex showing ferromagnetic coupling. Ab initio calculations were performed to understand the nature of magnetic coupling between the two lanthanide ions bridged by the anionic arene ligand and the origin of single-molecule-magnet behavior.

  14. Spatial gradients of polychlorinated biphenyls (PCBs) and organochlorine pesticides

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spatial gradients of polychlorinated biphenyls (PCBs) and organochlorine pesticides were examined in the young-of-the-year (YOY) blue多sh collected in the vicinity of...

  15. 77 FR 54818 - Polychlorinated Biphenyls (PCBs): Revisions to Manifesting Regulations

    Science.gov (United States)

    2012-09-06

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 761 RIN 2050-AG71 Polychlorinated Biphenyls (PCBs): Revisions to Manifesting Regulations AGENCY: Environmental Protection Agency (EPA). ACTION: Direct final rule. SUMMARY:...

  16. 77 FR 54863 - Polychlorinated Biphenyls (PCBs): Revisions to Manifesting Regulations

    Science.gov (United States)

    2012-09-06

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 761 ] RIN 2050-AG71 Polychlorinated Biphenyls (PCBs): Revisions to Manifesting... CFR Part 761 Environmental protection, Hazardous substances, Manifest, Polychlorinated...

  17. Adaptation mechanisms of bacteria during the degradation of polychlorinated biphenyls in the presence of natural and synthetic terpenes as potential degradation inducers.

    Science.gov (United States)

    Zorádová-Murínová, Slavomíra; Dudášová, Hana; Lukáčová, Lucia; Certík, Milan; Silharová, Katarína; Vrana, Branislav; Dercová, Katarína

    2012-06-01

    In this study, we examined the effect of polychlorinated biphenyls (PCBs) in the presence of natural and synthetic terpenes and biphenyl on biomass production, lipid accumulation, and membrane adaptation mechanisms of two PCB-degrading bacterial strains Pseudomonas stutzeri and Burkholderia xenovorans LB400. According to the results obtained, it could be concluded that natural terpenes, mainly those contained in ivy leaves and pine needles, decreased adaptation responses induced by PCBs in these strains. The adaptation processes under investigation included growth inhibition, lipid accumulation, composition of fatty acids, cis/trans isomerization, and membrane saturation. Growth inhibition effect decreased upon addition of these natural compounds to the medium. The amount of unsaturated fatty acids that can lead to elevated membrane fluidity increased in both strains after the addition of the two natural terpene sources. The cells adaptation changes were more prominent in the presence of carvone, limonene, and biphenyl than in the presence of natural terpenes, as indicated by growth inhibition, lipid accumulation, and cis/trans isomerization. Addition of biphenyl and carvone simultaneously with PCBs increased the trans/cis ratio of fatty acids in membrane fractions probably as a result of fluidizing effects of PCBs. This stimulation is more pronounced in the presence of PCBs as a sole carbon source. This suggests that PCBs alone have a stronger effect on bacterial membrane adaptation mechanisms than when added together with biphenyl or natural or synthetic terpenes.

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

    Science.gov (United States)

    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...

  19. Structural characterization of Pandoraea pnomenusa B-356 biphenyl dioxygenase reveals features of potent polychlorinated biphenyl-degrading enzymes.

    Directory of Open Access Journals (Sweden)

    Christopher L Colbert

    Full Text Available The oxidative degradation of biphenyl and polychlorinated biphenyls (PCBs is initiated in Pandoraea pnomenusa B-356 by biphenyl dioxygenase (BPDO(B356. BPDO(B356, a heterohexameric (αβ(3 Rieske oxygenase (RO, catalyzes the insertion of dioxygen with stereo- and regioselectivity at the 2,3-carbons of biphenyl, and can transform a broad spectrum of PCB congeners. Here we present the X-ray crystal structures of BPDO(B356 with and without its substrate biphenyl 1.6-Å resolution for both structures. In both cases, the Fe(II has five ligands in a square pyramidal configuration: H233 Nε2, H239 Nε2, D386 Oδ1 and Oδ2, and a single water molecule. Analysis of the active sites of BPDO(B356 and related ROs revealed structural features that likely contribute to the superior PCB-degrading ability of certain BPDOs. First, the active site cavity readily accommodates biphenyl with minimal conformational rearrangement. Second, M231 was predicted to sterically interfere with binding of some PCBs, and substitution of this residue yielded variants that transform 2,2'-dichlorobiphenyl more effectively. Third, in addition to the volume and shape of the active site, residues at the active site entrance also apparently influence substrate preference. Finally, comparison of the conformation of the active site entrance loop among ROs provides a basis for a structure-based classification consistent with a phylogeny derived from amino acid sequence alignments.

  20. Poly(meta-phenylene) Derivative with Rigid Twisted Biphenyl Units in Backbone: Synthesis, Structural Characterization,Photophysical Properties and Electroluminescence

    Institute of Scientific and Technical Information of China (English)

    ZHENG Yan; YANG Bing; ZHANG Hai-quan; LU Ping; SHEN Fang-zhong; LIU Lin-lin; XU Hai; YANG Guang-di; MA Yu-guang

    2007-01-01

    A soluble poly(meta-phenylene) derivative with rigid twisted biphenyl unit was synthesized by the Yamamoto coupling reaction. The polymer is soluble in common organic solvents, and the number-average molecular weight is about 6500. The UV-Vis and quantum chemical calculation indicate that the different conformation segments named "conformers" exist in the polymer backbones; it was also further confirmed by the single crystal X-ray diffraction study of the dimeric model compound. The π-π* transition of biphenyl segments of twisted and planar conformations made the polymer exhibit a strong absorption around 256 nm and a weak absorption at about 300 nm. Furthermore,the polymer exhibits a strong UV photoluminescence at 372 nm when the excitation wavelengths are longer than 300 nm. The ultraviolet-emitting electroluminescence(EL) device with the single layer structure shows EL λmax of the derivative at 370 nm.

  1. Mesomorphic, dielectric, and optical properties of fluorosubstituted biphenyls, terphenyls, and quaterphenyls

    Science.gov (United States)

    Kula, P.; Spadło, A.; Dziaduszek, J.; Filipowicz, M.; Dąbrowski, R.; Czub, J.; Urban, S.

    2008-12-01

    Compounds with moderate and large negative dielectric anisotropy (Δɛ) are very attractive liquid crystal (LC) for vertical alignment mode (VA). Materials with such properties can be achieved by lateral substitution of a polar group into a mesogenic molecule. We synthesized some new LC materials with a negative value of Δɛ, a moderately high birefringence (Δn), and a low viscosity. The mesomorphic and physical behaviour of the novel biphenyls, terphenyls and quaterphenyls fluorosubstituted in the rigid core and also with fluorinated alkyl and alkoxy chains are investigated. The prepared series of four LC compounds are promising for new LC mixtures for various applications. Examples of nematic mixtures with Δɛ˜-3.25 will be presented.

  2. (Biphenyl-4-yl)methylammonium chlorides: potent anticonvulsants that modulate Na+ currents.

    Science.gov (United States)

    Lee, Hyosung; Park, Ki Duk; Yang, Xiao-Fang; Dustrude, Erik T; Wilson, Sarah M; Khanna, Rajesh; Kohn, Harold

    2013-07-25

    We have reported that compounds containing a biaryl linked unit (Ar-X-Ar') modulated Na(+) currents by promoting slow inactivation and fast inactivation processes and by inducing frequency (use)-dependent inhibition of Na(+) currents. These electrophysiological properties have been associated with the mode of action of several antiepileptic drugs. In this study, we demonstrate that the readily accessible (biphenyl-4-yl)methylammonium chlorides (compound class B) exhibited a broad range of anticonvulsant activities in animal models, and in the maximal electroshock seizure test the activity of (3'-trifluoromethoxybiphenyl-4-yl)methylammonium chloride (8) exceeded that of phenobarbital and phenytoin upon oral administration to rats. Electrophysiological studies of 8 using mouse catecholamine A-differentiated cells and rat embryonic cortical neurons confirmed that 8 promoted slow and fast inactivation in both cell types but did not affect the frequency (use)-dependent block of Na(+) currents.

  3. Persistent organochlorine residues and toxic evaluation of polychlorinated biphenyls in sharks from the Mediterranean Sea (Italy)

    Energy Technology Data Exchange (ETDEWEB)

    Storelli, M.M.; Marcotrigiano, G.O. [Bari Univ., Dip. Farmaco-Biologico, Bari (Italy)

    2001-07-01

    Persistent organochlorines such as polychlorinated biphenyls including coplanar congeners, DDT compounds and HCB were measured in different tissues (muscle, liver and eggs) of two Mediterranean shark species: namely Centrophorus granulosus and Squalus blainvillei. The concentrations of organochlorines in the tissues and organs of both species were in the order DDTs>PCBs>HCB. The highest values of DDTs, PCBs and HCB were found in liver followed by eggs and muscle. Among DDTs the compound found in greatest concentration was p,p -DDE. The PCB profiles were dominated by congeners 138, 153, and 180. The isomers with higher TEQs values were non- and mono-ortho congeners than di-ortho ones in muscle, liver and eggs of both species. Among the non-ortho, PCB 126 was the major contributing individual to the total TEQs in both species. (Author)

  4. Bioactivation of dibrominated biphenyls by cytochrome P450 activity to metabolites with estrogenic activity and estrogen sulfotransferase inhibition capacity.

    Science.gov (United States)

    van Lipzig, Marola M H; Commandeur, Jan N; de Kanter, Frans J J; Damsten, Micaela C; Vermeulen, Nico P E; Maat, Evelina; Groot, Ed J; Brouwer, Abraham; Kester, Monique H A; Visser, Theo J; Meerman, John H N

    2005-11-01

    Exposure of humans and wildlife to xenobiotics, such as halogenated biphenyls, that interfere with the endogenous estrogen balance may lead to endocrine disruption. Such compounds may either mimic or block estradiol's action by agonistic or antagonistic action, respectively. They may also affect endogenous estradiol concentrations by induction or inhibition of enzymes that metabolize estradiol. In the present study, we demonstrate that estrogenic metabolites of two brominated biphenyls, 2,2'-dibromobiphenyl (2,2'-DBB) and 4,4'-dibromobiphenyl (4,4'-DBB), are formed by rat liver microsomal cytochrome P450 (CYP) activity. Bioactivation of 2,2'-DBB and 4,4'-DBB yielded various mono- and dihydroxylated bromobiphenyl metabolites, which were collected by preparative HPLC and analyzed by LC/MS. Several of the metabolites bound to the estrogen receptor (ER) activated the ER and inhibited human estrogen sulfotransferase (hEST). Seven monohydroxylated metabolites were positively identified using synthetic monohydroxylated reference compounds. These synthetic monohydroxylated bromobiphenyls also bound to and activated the ER and inhibited hEST. The highest ER affinity was observed for 4-OH-2,2'-DBB, with an EC50 of 6.6 nM. The highest ER activation was observed for 4-OH-3,4'-DBB (EC50 of 74 nM) while 4-OH-4'-MBB and 4-OH-2,2'-DBB induced a supramaximal (as compared to estradiol) ER activation. The strongest hEST inhibition was found with 4-OH-3,4'-DBB (EC50 = 40 nM). In conclusion, we show that two dibrominated biphenyls are bioactivated by CYP activity into very potent estrogenic metabolites and inhibitors of hEST. These findings are of vital importance for accurate risk assessment of exposure to environmental contaminants, such as halogenated biphenyls. Neglecting bioactivation through biotransformation will lead to underestimation of health risks of this class of xenobiotics.

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

    Energy Technology Data Exchange (ETDEWEB)

    Agudo, Antonio, E-mail: a.agudo@iconcologia.net [Unit of Nutrition, Environment, and Cancer, Cancer Epidemiology Research Program, Catalan Institute of Oncology (ICO), IDIBELL, Av. Gran Via no 199-203, 08907 L' Hospitalet de Llobregat (Spain); Goni, Fernando [Laboratorio de Salud Publica de Guipuzcoa, 20013 San Sebastian (Spain); CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Etxeandia, Arsenio [Laboratorio de Salud Publica de Vizcaya, 48010 Bilbao (Spain); Vives, Asuncion [Laboratorio Unificado Donostia, Hospital N. S. Aranzazu, 20014 San Sebastian (Spain); Millan, Esmeralda [Departamento de Quimica Aplicada, Universidad del Pais Vasco, Facultad de Quimica, 20080 San Sebastian (Spain); Lopez, Raul [CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Amiano, Pilar [CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Direccion de Salud de Guipuzcoa, 20013 San Sebastian (Spain); Ardanaz, Eva; Barricarte, Aurelio [CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Instituto de Salud Publica de Navarra, 31003 Pamplona (Spain); Dolores Chirlaque, M. [CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Consejeria de Sanidad, 3008 Murcia (Spain); Dorronsoro, Miren [CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Direccion de Salud de Guipuzcoa, 20013 San Sebastian (Spain); Jakszyn, Paula [Unit of Nutrition, Environment, and Cancer, Cancer Epidemiology Research Program, Catalan Institute of Oncology (ICO), IDIBELL, Av. Gran Via no 199-203, 08907 L' Hospitalet de Llobregat (Spain); Larranaga, Nerea [CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Direccion de Salud de Guipuzcoa, 20013 San Sebastian (Spain); Martinez, Carmen [CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Escuela Andaluza de Salud Publica, 18080 Granada (Spain); Navarro, Carmen [CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Consejeria de Sanidad, 3008 Murcia (Spain); Rodriguez, Laudina [Consejeria de Salud y Servicios Sanitarios de Asturias, 33001 Oviedo (Spain); 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.

  6. Syntheses and reactions of some new 2-arylidene-4-(biphenyl-4-yl)-but-3-en-4-olides with a study of their biological activity.

    Science.gov (United States)

    Khan, M S Y; Husain, A

    2002-07-01

    2-Arylidene-4-(biphenyl-4-yl)but-3-en-4-olides also known as 3-arylidene-5-(biphenyl-4-yl)-2(3H)-furanones were prepared from 3-(4-phenyl-benzoyl) propionic acid and aromatic aldehydes. Some of the selected butenolides were reacted with ammonia and benzylamine to give corresponding pyrrolones and N-benzylpyrrolones respectively, which were characterized on the basis of 1H NMR and MS data and elemental analysis results. These compounds were tested for anti-inflammatory and anti-microbial actions. A few compounds were found to have promising anti-inflammatory activity while a fair in number of compounds showed a good anti-fungal activity and a promising antibacterial activity against S. aureus and E. coli.

  7. Polychlorinated biphenyls and links to cardiovascular disease.

    Science.gov (United States)

    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.

  8. Formation of biphenyl and dibenzofuran phytoalexins in the transition zones of fire blight-infected stems of Malus domestica cv. 'Holsteiner Cox' and Pyrus communis cv. 'Conference'.

    Science.gov (United States)

    Chizzali, Cornelia; Khalil, Mohammed N A; Beuerle, Till; Schuehly, Wolfgang; Richter, Klaus; Flachowsky, Henryk; Peil, Andreas; Hanke, Magda-Viola; Liu, Benye; Beerhues, Ludger

    2012-05-01

    In the rosaceous subtribe Pyrinae (formerly subfamily Maloideae), pathogen attack leads to formation of biphenyls and dibenzofurans. Accumulation of these phytoalexins was studied in greenhouse-grown grafted shoots of Malus domestica cv. 'Holsteiner Cox' and Pyrus communis cv. 'Conference' after inoculation with the fire blight bacterium, Erwinia amylovora. No phytoalexins were found in leaves. However, both classes of defence compounds were detected in the transition zone of stems. The flanking stem segments above and below this zone, which were necrotic and healthy, respectively, were devoid of detectable phytoalexins. The transition zone of apple stems contained the biphenyls 3-hydroxy-5-methoxyaucuparin, aucuparin, noraucuparin and 2'-hydroxyaucuparin and the dibenzofurans eriobofuran and noreriobofuran. In pear, aucuparin, 2'-hydroxyaucuparin, noreriobofuran and in addition 3,4,5-trimethoxybiphenyl were detected. The total phytoalexin content in the transition zone of pear was 25 times lower than that in apple. Leaves and stems of mock-inoculated apple and pear shoots lacked phytoalexins. A number of biphenyls and dibenzofurans were tested for their in vitro antibacterial activity against some Erwinia amylovora strains. The most efficient compound was 3,5-dihydroxybiphenyl (MIC=115 μg/ml), the immediate product of biphenyl synthase which initiates phytoalexin biosynthesis.

  9. 75 FR 34076 - Polychlorinated Biphenyls (PCBs); Reassessment of Use Authorizations; Extension of Comment Period...

    Science.gov (United States)

    2010-06-16

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 761 RIN 2070-AJ38 Polychlorinated Biphenyls (PCBs); Reassessment of Use Authorizations..., Hazardous substances, Labeling, Polychlorinated biphenyls (PCBs), Reporting and recordkeeping...

  10. Identification of a novel dimethoxylated polybrominated biphenyl bioaccumulating in marine mammals

    Energy Technology Data Exchange (ETDEWEB)

    Marsh, G.; Athanasiadou, M.; Bergman, Aa.; Athanassiadis, I. [Department of Environmental Chemistry, Stockholm (Sweden); Endo, Tetsuya [Health Sciences Univ. of Hokkaido (Japan). Fac. of Pharmaceutical Sciences; Haraguchi, Koichi [Daiichi College of Pharmaceutical Sciences, Fukuoka (Japan)

    2004-09-15

    The screening of persistent halogenated organic pollutants has in recent years ended up with findings of numerous compounds being natural products. These compounds have preferably been reported from the marine environment and comprise, several hydroxylated and methoxylated polybrominated diphenyl ethers (OH-PBDEs and MeO-PBDEs) including monochlorinated ditto, a dimethoxylated polybrominated diphenyl ether i.e. 2',6-dimethoxy-2,3',4,5'-tetrabromodiphenyl ether, four halogenated dimethylated bipyrroles (HDBPs) with a 2,2'-bipyrrole backbone, a heptachlorinated 1,2'-bipyrrole i.e. heptachloro-1'-methyl-1,2'-bipyrrole (Q1)6 and a halogenated monoterpene holding two bromine and three chlorine atoms. We have taken interest in an organobrominated compound with an unknown structure but with a molecule ion of m/z = 526 and a four bromine isotope pattern according to mass spectrometry (MS), detected in marine mammal samples of which the majority were collected from Japanese coastal waters. This compound has recently been reported from several marine mammals collected on the Southern hemisphere, but neither the chemical structure nor the type of substance group were established. We here report the structure of this organobrominated compound, a dimethoxylated polybrominated biphenyl, which likely is of natural origin. The identification was done by the comparison of relative retention time (RRT) on two GC columns with different polarities and by comparing mass spectra from three different ionization techniques i.e. PICI, ECNI and EI, of the unknown compound from the samples with an authentic reference compound. Levels of the novel dimethoxylated polybrominated biphenyl are reported as well as the levels (for comparison) of some other known polybrominated compounds, both brominated flame retardants (BFRs) and natural products i.e. BDE-47, BDE-99, BDE-100, BDE-153, BDE-154, BDE-183, 1,2,5,6,9,10- hexabromocyclododecane (HBCDD), 6-MeO-BDE-47, 2

  11. Hydroxy and methylsulfone metabolites of polychlorinated biphenyls in the human blood and tissues

    Energy Technology Data Exchange (ETDEWEB)

    Masuda, Yoshito; Haraguchi, Koichi [Daiichi College of Pharmaceutical Sciences, Fukuoka (Japan)

    2004-09-15

    Polychlorinated biphenyls (PCBs) are a group of chlorinated compounds which have polluted the global environment, persistently retained in wildlife and humans, and eventually affected the human health. PCBs are biotransformed to mainly hydroxy (HO-) and methylsulfone (MeSO{sub 2}-) metabolites in the animal and human tissues. About ten thousands of chemical and biological researches on PCBs, HOPCBs and MeSO{sub 2}-PCBs have been reported and reviewed so far. Letcher et al. cleverly reviewed the HO-PCBs and MeSO2-PCBs in 2000. We review the contamination of HO-PCBs and MeSO{sub 2}-PCBs in human tissues and their possible effects to human health. Different positional numberings of Cl-, HO- and MeSO{sub 2}- on biphenyl rings were used by different authors. Then, nomenclature of PCB metabolite was assessed by Maervoet et al. and they suggested to use the IUPAC chemical name and number of parent PCB congener with the subsequent assignment of the phenyl ring position number of the HO- or MeSO{sub 2}- substituent number afterward.

  12. The associations between the environmental exposure to polychlorinated biphenyls (PCBs) and breast cancer risk and progression

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Polychlorinated biphenyls(PCBs) are chlorinated biphenyl compounds with wide applications in the industry.In spite of a ban on their production in the late 1970s,PCBs,as a group of POPs,are still persistent and widely spread in the environment,posing potential threats to human health.The role of PCBs as etiologic agents for breast cancer has been intensively explored in a variety of in vivo,animal and epidemiologic studies.Initial investigations indicated higher levels of PCBs in mammary tissues or sera corresponded to the occurrence of breast cancer,but later studies showed no positive association between PCB exposure and breast cancer development.More recent data suggested that the CYP1A1 m2 polymorphisms might add increased risk to the etiology of breast cancer in women with environmental exposure to PCBs.PCBs are implicated in advancing breast cancer progression,and our unpublished data reveals that PCBs activate the ROCK signaling to enhance breast cancer metastasis.Therefore,the correlation between PCB exposure and breast cancer risk warrants further careful investigations.

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

    Science.gov (United States)

    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...

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

    Science.gov (United States)

    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...

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

    Directory of Open Access Journals (Sweden)

    Hyeon-Yeong Kim

    2015-05-01

    Full Text Available 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.

  16. Polychlorinated Biphenyls (PCB) Residue Effects Database

    Data.gov (United States)

    U.S. Environmental Protection Agency — The PCB Residue Effects (PCBRes) Database was developed to assist scientists and risk assessors in correlating PCB and dioxin-like compound residues with toxic...

  17. Modeling organic compounds in the estuarine and coastal environment

    NARCIS (Netherlands)

    R.W.P.M. Laane; D. van de Meent; P. de Voogt; J. Parsons; J. Hendriks; J. van Gils

    2011-01-01

    This chapter describes the historical development and present applications of water-quality models for organic chemical compounds (e.g., polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs)). Various types of water-quality models are described, varying in the amount of compar

  18. Substituted N-(biphenyl-4'-yl)methyl (R)-2-acetamido-3-methoxypropionamides: potent anticonvulsants that affect frequency (use) dependence and slow inactivation of sodium channels.

    Science.gov (United States)

    Lee, Hyosung; Park, Ki Duk; Torregrosa, Robert; Yang, Xiao-Fang; Dustrude, Erik T; Wang, Yuying; Wilson, Sarah M; Barbosa, Cindy; Xiao, Yucheng; Cummins, Theodore R; Khanna, Rajesh; Kohn, Harold

    2014-07-24

    We prepared 13 derivatives of N-(biphenyl-4'-yl)methyl (R)-2-acetamido-3-methoxypropionamide that differed in type and placement of a R-substituent in the terminal aryl unit. We demonstrated that the R-substituent impacted the compound's whole animal and cellular pharmacological activities. In rodents, select compounds exhibited excellent anticonvulsant activities and protective indices (PI=TD50/ED50) that compared favorably with clinical antiseizure drugs. Compounds with a polar, aprotic R-substituent potently promoted Na+ channel slow inactivation and displayed frequency (use) inhibition of Na+ currents at low micromolar concentrations. The possible advantage of affecting these two pathways to decrease neurological hyperexcitability is discussed.

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

    OpenAIRE

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

    2000-01-01

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

  20. Hydrogenation properties of transition metals massic sulfides in the biphenyl conversion; Propriedades hidrogenantes de sulfetos massicos de metais de transicao na conversao da bifenila

    Energy Technology Data Exchange (ETDEWEB)

    Afonso, Julio Carlos [Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst. de Quimica. Dept. de Quimica Analitica; Lacroix, Michel; Boutarfa, Naima; Guillard, Chantal; Vrinat, Michel; Portefaix, Louis [Centre National de la Recherche Scientifique (CNRS), 69 - Villeurbanne (France). Inst. de Recherches sur la Catalyse; Breysse, Michele [Universite Pierre et Marie Curie, 75 - Paris (France). Lab. de Reactivite de Surface

    1998-07-01

    Catalytic activities of some unsupported transition metal sulfides (TMS) were determined on biphenyl conversion under the experimental procedure given by Lacroix et alii. Data from new samples confirmed the general tendencies previously observed, which are in agreement with literature results for conversion of aromatic model compounds over TMS: the third-row TMS were the most active with maximum at Ir sulfide. Group V sulfides (Nb, Ta) showed high cracking activity of phenylcyclohexane into benzene + cyclohexane. (author)

  1. STUDIES OF THE SUBSTITUTION EFFECTS ON THE ELECTRONIC PROPERTIES FOR BIPHENYL AND DERIVATIVE MOLECULES BY USING DFT METHOD

    Directory of Open Access Journals (Sweden)

    Rajaa Khedir Al-Yasari

    2016-06-01

    Full Text Available DFT method has been carried out to study the substitution effects of NO2 group on the electronic (ionization potential, electron affinity, electronegativity, hardness, softness and electrophilicity index and IR spectral properties of biphenyl and derivative molecules by using the B3LYP functional and the 3-21G basis set, as well as the optimization structure. The calculated values of HOMO and LUMO energies, as well as predicted by ChemBioDraw program 1H and 13C NMR spectra for the studied compounds are in a good agreement with experimental data.

  2. Polychlorinated biphenyls and organochlorine pesticides in atmospheric air of the Northern Hovsgol region in 2008-2013

    Science.gov (United States)

    Mamontova, E. A.; Tarasova, E. N.; Goreglyad, A. V.; Tkachenko, L. L.; Mamontov, A. A.; Kuzmin, M. I.

    2015-10-01

    Results of the study of organochlorine pesticides (OCP) and polychlorinated biphenyls (PCB) from the listing of the Stockholm Convention in atmospheric air of the Northern Hovsgol region at the base of the "Khankh" stationary, Institute of Geochemistry, Siberian Branch, Russian Academy of Sciences, in 2008-2013 in the absence of clear sources of these compounds are considered. Quantitative and qualitative changes in the concentration of PCB and OCP in atmospheric air of the Northern Hovsgol region in 2008-2013 characterizing the influence of natural (annual temperature variations) and anthropogenic (atmospheric transportation from the territories of neighboring countries) are shown.

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

    Science.gov (United States)

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

    1996-01-01

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

  4. Polychlorinated biphenyl exposure and deiodinase activity in young infants

    NARCIS (Netherlands)

    Soechitram, Shalini D; Berghuis, Sietske A; Visser, Theo J; Sauer, Pieter J J

    2017-01-01

    BACKGROUND: Several studies have shown effects of polychlorinated biphenyls (PCBs) on serum thyroid hormone levels in pregnant woman and their infants, while other studies did not find such effects. How PCBs might affect thyroid hormone metabolism, is still unclear. Potential mechanisms are direct i

  5. Danish emission inventory for hexachlorobenzene and polychlorinated biphenyls

    DEFF Research Database (Denmark)

    Nielsen, Ole-Kenneth; Plejdrup, Marlene Schmidt; Winther, Morten;

    This report documents the improved air emission inventories for hexachlorobenzene (HCB) and polychlorinated biphenyls (PCBs). The emission inventories now include all sources covered by the EMEP/EEA Guidebook. The completeness and accuracy of the inventories for these pollutants have been...

  6. Comparison of polychlorinated biphenyl levels across studies of human neurodevelopment

    NARCIS (Netherlands)

    Longnecker, MP; Gladen, BC; Brock, JW; Grandjean, P; Jacobson, JL; Korrick, SA; Rogan, WJ; Weisglas-Kuperus, N; Hertz-Picciotto, [No Value; Ayotte, P; Stewart, P; Winneke, G; Charles, MJ; Jacobson, SW; Dewailly, E; Boersma, ER; Altshul, LM; Heinzow, B; Pagano, JJ; Jensen, AA

    2003-01-01

    Polychlorinated biphenyls (PCBs) are persistent pollutants that are ubiquitous in the food chain, and detectable amounts are in the blood of almost every person in most populations that have been examined. Extensive evidence from animal studies shows that PCBs are neurotoxins, even at low doses. Int

  7. Electro-optic and dynamic studies of biphenyl benzoate ferroelectric liquid crystals

    Energy Technology Data Exchange (ETDEWEB)

    Hemine, J., E-mail: hemine1@yahoo.f [Laboratoire de Physique de la Matiere Condensee, Universite Hassan II, Mohammedia-Casablanca, BP 146, F.S.T. Mohammedia (Morocco); Daoudi, A. [Universite Lille Nord de France, F-59000 Lille (France); ULCO, LDSMM, F-59140 Dunkerque (France); CNRS UMR8024, F-59140 Dunkerque (France); Legrand, C. [Universite Lille Nord de France, F-59000 Lille (France); ULCO, LEMCEL, F-62228 Calais (France); El kaaouachi, A.; Nafidi, A. [Laboratoire de Physique de la Matiere Condensee, Faculte des Sciences Ibnou Zohr, BP 28/S 80000 Agadir (Morocco); Ismaili, M.; Isaert, N. [Universite Lille Nord de France, F-59000 Lille (France); USTL, LDSMM, F-59655 Villeneuve d' Ascq (France); CNRS UMR8024, F-59655 Villeneuve d' Ascq (France); Nguyen, H.T. [Centre de Recherche Paul Pascal, Universite de Bordeaux 1, 33600 Pessac (France)

    2010-05-01

    We present electro-optic and dynamic properties on three homologous of biphenyl benzoate series of ferroelectric liquid crystals (FLCs) exhibiting the chiral smectic C phase (SmC*). The three compounds present high spontaneous polarization and show the SmC*-SmA*-N* phase sequence. Dielectric spectroscopy was used to provide the dynamics and dipolar ordering of the ferroelectric phase. The Goldstone relaxation mode was studied for sample cells on planar geometry without a DC bias voltage. The rotational viscosity corresponding to molecular motions in the SmC* phase was determined from dielectric measurements. The Arrhenius-type behavior of the rotational viscosity was found and the corresponding activation energies were evaluated.

  8. [Application prospect about bioremediation of polychlorinated biphenyls-contaminated soil with immobilized microorganism technique: a review].

    Science.gov (United States)

    Hu, Jin-Xing; Su, Xiao-Mei; Han, Hui-Bo; Shen, Chao-Feng; Shi, Ji-Yan

    2014-06-01

    As one type of the persistent organic pollutants, polychlorinated biphenyls (PCBs) are tremendously harmful to organisms. These compounds are easily absorbed onto soil particles and able to accumulate in soil after they are released into the environment. Bioremediation technology of PCBs-contaminated soils has become a research hotspot in recent years, and immobilized microorganism technique has high developing and applying value because of its unique advantages in environmental remediation. This paper reviewed the chief remediation technology of PCBs-contaminated soils and then analyzed the characteristics of immobilized microorganism technique and its research progress in remediation of organic polluted soil. Finally, the feasibility and problems of this technique in remediation of PCBs-contaminated soil were also discussed.

  9. Prediction of mutagenicity and carcinogenicity using in silico modelling: A case study of polychlorinated biphenyls.

    Science.gov (United States)

    Vračko, M; Bobst, S

    2015-01-01

    In silico modelling is an important alternative method for the evaluation of properties of chemical compounds. Basically, two concepts are used in its applications: QSAR modelling for endpoint predictions, and grouping (categorization) of large groups of chemicals. In the presented report we address both of these concepts. As a case study we present the results on a set of polychlorinated biphenyls (PCBs) and some of their metabolites. Their mutagenicity and carcinogenic potency were evaluated with CAESAR and T.E.S.T. models, which are freely available over the internet. We discuss the value and reliability of the predictions, the applicability domain of models and the ability to create prioritized groupings of PCBs as a category of chemicals.

  10. Temperature of hydrogen radio frequency plasma under dechlorination process of polychlorinated biphenyls

    Science.gov (United States)

    Inada, Y.; Abe, K.; Kumada, A.; Hidaka, K.; Amano, K.; Itoh, K.; Oono, T.

    2014-10-01

    It has been reported that RF (radio frequency) hydrogen plasmas promote the dechlorination process of PCBs (polychlorinated biphenyls) under irradiation of MW (microwave). A relative emission intensity spectroscope system was used for single-shot imaging of two-dimensional temperature distributions of RF hydrogen plasmas generated in chemical solutions with several mixing ratios of isopropyl alcohol (IPA) and insulation oil under MW irradiation. Our experimental results showed that the plasma generation frequencies for the oil-contaminating solutions were higher than that for the pure IPA solution. In addition, the plasma temperature in the compound liquids including both oil and IPA was higher than that in the pure IPA and oil solutions. A combination of the plasma temperature measurements and plasma composition analysis indicated that the hydrogen radicals generated in a chemical solution containing the equal volumes of IPA and oil were almost the same amounts of H and H+, while those produced in the other solutions were mainly H.

  11. Polychlorinated biphenyl concentrations in adipose tissue and abdominal obesity in the elderly

    DEFF Research Database (Denmark)

    Bräuner, Elvira; Raaschou-Nielsen, Ole; Andersen, Zorana

    2013-01-01

    cessation of smoking, but these do not fully explain the epidemic. Polychlorinated biphenyl congeners (PCBs) are endocrine-disrupting chemicals and evidence from animal experiments suggests an association with obesity development. Our knowledge of the effects of these compounds on weight gain in humans...... is limited. Our objective was to investigate the association between exposure to PCBs experienced by a general Danish population and development of obesity. We randomly selected 204 persons (113 obese and 91 overweight), aged ≥ 50 years, from a prospective Danish cohort of 57,053 persons and examined ten...... PCBs as potential determinants of abdominal obesity. Adipose tissue was collected upon enrolment and PCBs were quantified using gas chromatography-mass spectroscopy. Median levels of the included PCBs were lower in women, except for PCB118 and all PCBs were positively associated with increased...

  12. Growth abnormalities in the population exposed in utero and early postnatally to polychlorinated biphenyls and dibenzofurans

    Energy Technology Data Exchange (ETDEWEB)

    Yueliang L. Guo; Chen-Chin Hsu [National Cheng Kung Univ. Medical College, Tainan (Taiwan, Province of China); Lambert, G.H. [UMDNJ-Robert Wood Johnson Medical School, New Brunswick, NJ (United States)

    1995-09-01

    This article reviews the findings in children exposed to various levels of polychlorinated biphenyls (PCBs) and related compounds in utero and early postnatally. Yu-Cheng ({open_quotes}oil-disease{close_quotes}) mothers were Taiwanese women exposed to PCBs and their heat-degradation products form the ingestion of contaminated rice oil in 1979. Children of these mothers were born growth retarded, with dysmorphic physical findings, and delayed cognitive development compared with unexposed children. In this article, findings in Yu-Cheng children born between 1978 and 1985 are summarized and compared with two other well-documented cohorts of children prenatally exposed to different levels of PCBs. Results of the investigation in Yu-Cheng children will provide important information about the toxicities, health effects, and mechanisms of PCB/PCDF exposure and demonstrate that the developing human is more sensitive than the adult to the toxic effects of these chemicals. 53 refs., 2 tabs.

  13. Digestive tract absorption of polychlorinated dibenzo-p-dioxins, dibenzofurans, and biphenyls in a nursing infant

    Energy Technology Data Exchange (ETDEWEB)

    McLachlan, M.S. (Univ. of Bayreuth (Germany))

    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.

  14. Soil-Air Partitioning of Polychlorinated Biphenyls and Total Dichloro-Diphenyl-Trichloroethanes

    Institute of Scientific and Technical Information of China (English)

    Yaping Zhang; Erping Bi; Honghan Chen

    2014-01-01

    Soil-air partitioning is an important diffusive process that affects the environmental fate of organic compounds and human health. In this review, factors affecting the soil-air partitioning of polychlorinated biphenyls (PCBs) and total dichloro-diphenyl-trichloroethanes (p,p’-and o,p’-isomers of DDT, DDD, and DDE) are discussed. Hydrophobicity is an important factor that influences soil-air partition coefficients (KSA), and its effect can be explained through enthalpy of phase change for soil-air partitioning transfer (ΔHSA). For more hydrophobic compounds, a sharp increase in the KSA of PCBs and organochlorines can be seen in the early aging period. During the aging period, the temperature has a significant effect on the more hydrophobic organic compounds. The content and properties of soil or-ganic matter influence the KSA of the target compounds. Generally, KSA decreases with increasing rela-tive humidity in soils. The linear trend between KSA and temperature (T) changes at 0 °C. Freezing the air or soil in experiments would change the research results. On the basis of factors influencing soil-air partitioning, a multipleparameter (T, organic carbon fraction (fOC), and octanol-air partition coefficient (KOA)) model is put forward to predict the KSA values for PCBs and total DDTs.

  15. 2-(Biphenyl-4-ylacetic acid (felbinac

    Directory of Open Access Journals (Sweden)

    Lynne S. Taylor

    2010-10-01

    Full Text Available The structure of the title compound, C14H12O2, displays the expected intermolecular hydrogen bonding of the carboxylic acid groups, forming dimers. The dihedral angle between the two aromatic rings is 27.01 (7°.

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

    Science.gov (United States)

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

    1971-01-01

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

  17. Binding of Estrogenic Compounds to Recombinant Estrogen Receptor-α: Application to Environmental Analysis

    OpenAIRE

    Pillon, Arnaud; Boussioux, Anne-Marie; Escande, Aurélie; Aït-Aïssa, Sélim; Gomez, Elena; Fenet, Hélène; Ruff, Marc; Moras, Dino; Vignon, Françoise; Duchesne, Marie-Josèphe; Casellas, Claude; Nicolas, Jean-Claude; Balaguer, Patrick

    2004-01-01

    Estrogenic activity in environmental samples could be mediated through a wide variety of compounds and by various mechanisms. High-affinity compounds for estrogen receptors (ERs), such as natural or synthetic estrogens, as well as low-affinity compounds such as alkylphenols, phthalates, and polychlorinated biphenyls are present in water and sediment samples. Furthermore, compounds such as polycyclic aromatic hydrocarbons, which do not bind ERs, modulate estrogen activity by means of the aryl ...

  18. Binding of estrogenic compounds to recombinant estrogen receptor-alpha: application to environmental analysis.

    OpenAIRE

    Pillon, Arnaud; Boussioux, Anne-Marie; Escande, Aurélie; Aït-Aïssa, Sélim; Gomez, Elena; Fenet, Hélène; Ruff, Marc; Moras, Dino; Vignon, Françoise; Duchesne, Marie-Josèphe; Casellas, Claude; Nicolas, Jean-Claude; Balaguer, Patrick

    2005-01-01

    International audience; Estrogenic activity in environmental samples could be mediated through a wide variety of compounds and by various mechanisms. High-affinity compounds for estrogen receptors (ERs), such as natural or synthetic estrogens, as well as low-affinity compounds such as alkylphenols, phthalates, and polychlorinated biphenyls are present in water and sediment samples. Furthermore, compounds such as polycyclic aromatic hydrocarbons, which do not bind ERs, modulate estrogen activi...

  19. 水溶性联苯类化合物WLP-S-14在实验性肝损伤模型中的保护作用%Protective Effect of Water Soluble Biphenyl Compound WLP-S-14 on Experimental Liver Injury Model

    Institute of Scientific and Technical Information of China (English)

    苗露阳; 童元峰; 吴松; 魏怀玲; 鲍秀琦; 张丹; 张予阳; 孙华

    2014-01-01

    Objective To assess the hepatoprotective effect of a water solubility derivative of biphenyl by three acute liver failure models. Methods Two mice models of acute liver failure were established by injection with carbon tetrachlo-ride (CCl4) or concanavalin A(Con A) respectively. Mice were intraperitoneally injected with two doses of WLP-S-14 (100 200 mg·kg-1) before administration of CCl4 and Con A. Serum alanine aminotransferase(ALT) and glutamate oxaloacetate transaminase (AST) were detected by automatic chemistry analyzer (TBA-40FR). At the same time, oxaliplatin and 5-fluorouracil were injected to induce liver failure in Lewis-bearing mice. WLP-S-14(100,200mg·kg-1) was pretreated 2hr before the injection of oxaliplatin/5-fluorouracil. The activities of ALT and AST in serum were measured by automatic chemistry analyzer and liver histopathological changes were examined by H.E. and light microscopy. Results In CCl4-induced liver damage mice, WLP-S-14 100mg·kg-1 significantly reduced the elevated serum AST and ALT levels induced by CCl4. WLP-S-14 200mg·kg-1 also markedly decreased sersum ALT, but there was no significantly statistical significance on the decrease of AST when compared with the model group. In Con A-induced immunologic liver injury mice, pretreation of WLP-S-14 (100 200mg·kg-1) both markedly decreased the elevated ALT and AST induced by Con A. WLP-S-14 (100, 200mg·kg-1) also showed a significant protection in oxaliplatin/5-fluorouracil-induced liver damage mice, as evidenced by the improvement of histopathological injury and the decrease of elevated serum aminotransferases. There was no decline to tumor inhibition rate produced by oxaliplatin/5-fluo-rouracilwhenco-administration WLP-S-14 100mg·kg-1. Conclusion WLP-S-14 showed potent protective activities against CCl4, Con A or oxaliplatin/5-fluorouracil-induced liver damage. It is worth exploring for future study.%目的:考察新型水溶性联苯类化合物WLP-S-14在3种实验性小鼠

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

    Science.gov (United States)

    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.

  1. Comparison of quadrupole and ion trap mass spectrometry for the analysis of polychlorinated biphenyls

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, E.; DeVita, W. [Univ. of Wisconsin, Stevens Point, WI (United States)

    1995-12-31

    Polychlorinated biphenyls (PCBs) are often analyzed using gas chromatography with an electron capture detector (GC/ECD) because of the sensitivity of this detection technique toward this class of compounds. However, use of gas chromatography/mass spectrometry (GC/MS) can provide additional selectivity, thus minimizing the likelihood of false positive results from interfering compounds. GC/MS provides a higher degree of confidence in the identification of the chromatographic peaks, but is often limited, in comparison to GC/ECL, by its sensitivity. The two most common mass analyzers used are quadrupole and ion trap detectors. In this study the authors propose to document the capabilities of both quadrupole and ion trap analyzer for analysis of PCBs. They will compare and contrast the sensitivities and linear ranges for these compounds. Sensitivities will be assessed by signal-to-noise ratio comparisons. Linearity of the calibrated range will also be investigated through evaluation of the relative response factors versus concentration of PCB for a fixed concentration of internal standard. Estimations will be made of the appropriate linear ranges on the two instruments and comparisons made in both the full scan and selected ion modes.

  2. 2-(Biphenyl-4-ylpropan-2-ol

    Directory of Open Access Journals (Sweden)

    David C. Liles

    2012-03-01

    Full Text Available The title compound, C15H16O, crystallizes with two independent molecules in the asymmetric unit. Due to the space-group symmetry, this results in the formation of a tetramer where the four molecules are connected by O—H...O hydrogen bonds. The molecules pack parallel to the c axis. Both molecules in the asymmetric unit are nonplanar and the dihedral angles between connected aromatic rings in each molecule are 7.96 (12 and 9.75 (13°. This contrasts with the gas phase density functional theory (DFT optimized conformation, where this dihedral angle is 39.33°.

  3. Liver function tests in workers with occupational exposure to polychlorinated biphenyls (PCBs): comparison with Yusho and Yu-Cheng

    Energy Technology Data Exchange (ETDEWEB)

    Fischbein, A.

    1985-05-01

    The results of liver function tests in a population manufacturing capacitors and transformers are presented. Two clinical field examinations were performed, one in 1976 when PCBs were still used in the manufacturing of the electrical equipment and one at the end of 1979, 2.5 years after discontinuation of PCBs use. A low prevalence of abnormal liver function tests was found and mean values for all tests were within normal laboratory ranges. At the initial examination, weak, but statistically significant correlations were found between log LDH and plasma levels of log HPCB (higher chlorinated congeners of polychlorinated biphenyls) and log TPCB (total polychlorinated biphenyls) among the female workers, while log el-GTP correlated significantly only with log HPCB among the male workers. A significant increase to abnormal levels of el-GTP was noted at the follow-up examination in both male and female workers, and preliminary results indicate significant correlations between el-GTP and serum levels of PCBs among the male workers. These findings are in accordance with previously reported data on populations occupationally exposed to PCBs, but differ from hepatic biochemistry findings in accidental poisonings due to ingestion of cooking oil contaminated with PCBs and related compounds, i.e., polychlorinated dibenzofurans (PCDFs) and polychlorinated quaterphenyls (PCQs). Hence, the importance of considering the related compounds as etiologic factors in PCB poisoning is emphasized.

  4. Sonochemical Degradation of Polychlorinated Biphenyls in Aqueous Solution

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Polychlorinated biphenyl (PCB) is a kind of persistent and dangerous environmental pollutants. This paper presented the research result of sonochemical degradation of 2-chloro- biphenyl (2-CBP), 4-chlorobiphenyl (4-CBP) and 4,4'-dichlorobiphenyl (4,4'-CBP)in water. The ultrasonic degradation kinetics of 2-CBP, 4-CBP and 4,4'-CBP in water were found to be first-order and the degradation rate coefficients are 3.69×10-2, 3.19×10-2 and 2.06×10-2 at 25±1°C for 2-CBP, 4-CBP and 4,4'-CBP respectively. The influence of initial concentrations, reaction temperature on the ultrasonic decomposition of 2-CBP were also investigated.

  5. Quantum Transport in a Biphenyl Molecule: Effects of Magnetic Flux

    OpenAIRE

    Maiti, Santanu K.

    2009-01-01

    Electron transport properties of a biphenyl molecule are studied based on the Green's function formalism. The molecule is sandwiched between two metallic electrodes, where each benzene ring is threaded by a magnetic flux $\\phi$. The results are focused on the effects of the molecule to electrode coupling strength and the magnetic flux $\\phi$. Our numerical study shows that, for a fixed molecular coupling, the current amplitude across the bridge can be {\\em regulated} significantly just by tun...

  6. Research progress of the endocrine disrupting activities of polychlorinated biphenyls

    Institute of Scientific and Technical Information of China (English)

    ZHOU Jingming; QIN Zhanfen; CONG Lin; XU Xiaobai

    2004-01-01

    Polychlorinated biphenyls (PCBs) are global persistent organic pollutants. Almost all commercial PCBs mixtures, single PCB congener, and their metabolites possess endocrine disrupting activities. They can disrupt the estrogen/androgen system, thyroid hormone system and other endocrine systems by interfering with the synthesis, transport, storage, metabolism, and feedback regulation of hormones. The newest data related to the endocrine disrupting activities of PCBs and their mechanisms are reviewed and the research perspectives are also discussed.

  7. Polychlorinated biphenyls and risk of testicular germ cell tumors

    OpenAIRE

    McGlynn, Katherine A.; Quraishi, Sabah M.; Graubard, Barry I.; Weber, Jean-Philippe; Rubertone, Mark V; Erickson, Ralph L.

    2009-01-01

    Exposure to endocrine disrupting chemicals, such as polychlorinated biphenyls (PCBs), may alter hormonal balance and thereby, increase risk of testicular germ cell tumors (TGCT). To study the relationship of PCBs to TGCT, pre-diagnostic serum samples from 736 cases and 913 controls in the Servicemen’s Testicular Tumor Environmental and Endocrine Determinants study were analyzed. Adjusted odds ratios (OR) and 95% confidence intervals (95%CI) were estimated using logistic regression. PCB levels...

  8. Polychlorinated Biphenyl Presence in the Columbia River Corridor

    Energy Technology Data Exchange (ETDEWEB)

    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.

  9. Synthesis and Anti-SIV Activity in vitro of Novel 4,4'-Dimethoxy-5,6,5',6'- dimethenedioxy-2-alkyloxycarbonyl Biphenyl Derivatives

    Institute of Scientific and Technical Information of China (English)

    CHENG,Sen-Xiang; WANG,Li-Min; CHANG,Jun-Biao; QU,Ling-Bo; CHEN,Rong-Feng; XIE,Jing-Xi

    2004-01-01

    @@ 4,4'-Dimethoxy-5,6,5',6'-dimethenedioxy-2,2'-dimethoxycarbonyl biphenyl (DDB, 1) and its derivatives show anti-HBV and anti-HIV activities.[1] However, their poor solubility was not in favor of bioavailability.[2,3] In addition,other anti-HIV agents[4] with piperazine moiety have been investigated. Their saturated nitrogen-containing heterocyclic groups play the role of pharmaco-effectivity.[5] It was assumed that the combination of DDB with substituted benzyl piperazines would produce some new compounds with activity against anti-HIV. Therefore, we designed and synthesized a class of novel 4,4'-dimethoxy-5,6,5',6'-dimethenedioxy biphenyls modified by substituted piperazines, and partly evaluated their anti-SIV activity.

  10. Subculturing of a polychlorinated biphenyl-dechlorinating anaerobic enrichment on solid media

    Energy Technology Data Exchange (ETDEWEB)

    May, H.D.; Boyle, A.W.; Price, W.A. II.; Blake, C.K. (Celgene Corp., Warren, NJ (United States))

    1992-12-01

    An anaerobic culture capable of dechlorinating polychlorinated biphenyls was subcultured under strict anaerobic conditions on solid media containing sterilized river sediment. The dechlorination activity was transferred as a bacterial colony on a solid medium three times. After two transfers on solid medium, the culture was no longer methanogenic but still dechlorinated a mixture of tri- and tetrachlorobiphenyls. This demonstrates that anaerobic bacteria are responsible for the polychlorinated biphenyl dechlorination and can be grown without polychlorinated biphenyl on solid media.

  11. Human biological monitoring of suspected endocrine-disrupting compounds

    Directory of Open Access Journals (Sweden)

    Moosa Faniband

    2014-02-01

    Full Text Available Endocrine-disrupting compounds are exogenous agents that interfere with the natural hormones of the body. Human biological monitoring is a powerful method for monitoring exposure to endocrine disrupting compounds. In this review, we describe human biological monitoring systems for different groups of endocrine disrupting compounds, polychlorinated biphenyls, brominated flame retardants, phthalates, alkylphenols, pesticides, metals, perfluronated compounds, parabens, ultraviolet filters, and organic solvents. The aspects discussed are origin to exposure, metabolism, matrices to analyse, analytical determination methods, determinants, and time trends.

  12. Structure-activity relationships for interaction with multidrug resistance protein 2 (ABCC2/MRP2): the role of torsion angle for a series of biphenyl-substituted heterocycles.

    Science.gov (United States)

    Lai, Yurong; Xing, Li; Poda, Gennadiy I; Hu, Yiding

    2007-06-01

    Multidrug resistance protein 2 (ABCC2/MRP2) is an ATP-binding cassette transporter involved in the absorption, distribution, and excretion of drugs and xenobiotics. Identifying compounds that are ABCC2/MRP2 substrates and/or inhibitors and understanding their structure-activity relationships (SARs) are important considerations in the selection and optimization of drug candidates. In the present study, the interactions between ABCC2/MRP2 and a series of biphenyl-substituted heterocycles were evaluated using Caco-2 cells and human ABCC2/MRP2 gene-transfected Madin-Darby canine kidney cells. It was observed that ABCC2/MRP2 transport and/or inhibition profile, both in nature and in magnitude, depends strongly on the substitution patterns of the biphenyl system. In particular, different ortho-substitutions cause various degrees of twisting between the two-phenyl rings, resulting in changing interactions between the ligands and ABCC2/MRP2. The compounds with small ortho functions (hydrogen, fluorine, and oxygen) and, thus, the ones displaying the smallest torsion angles of biphenyl (37-45 degrees) are neither substrates nor inhibitors of human ABCC2/MRP2. The transporter interactions increase as the steric bulkiness of the ortho-substitutions increase. When the tested compounds are 2-methyl substituted biphenyls, they exhibit moderate torsion angles (54-65 degrees) and behave as ABCC2/MRP2 substrates as well as mild inhibitors [10-40% compared with 3-[[3-[2-(7-chloroquinolin-2-yl)vinyl]phenyl]-(2-dimethylcarbamoylethyl-sulfanyl)methylsulfanyl] propionic acid (MK571)]. For the 2,2'-dimethyl substituted biphenyls, the torsions are enhanced (78-87 degrees) and so is the inhibition of ABCC2/MRP2. This class of compounds behaves as strong inhibitors of ABCC2/MRP2. These results can be used to define the three-dimensional structural requirements of ABCC2/MRP2 interaction with their substrates and inhibitors, as well as to provide SAR guidance to support drug discovery.

  13. Polychlorinated biphenyls (PCBs) residues in milk from an agroindustrial zone of Tuxpan, Veracruz, Mexico.

    Science.gov (United States)

    Pérez, J Jesús; León, Salvador Vega Y; Gutiérrez, Rey; López, Yanet; Faure, Roberto; Escobar, Arturo

    2012-10-01

    The coasts of the Gulf of Mexico are zones exposed to the exploration and exploitation of petroleum sources, and the products generated in agricultural zones may become contaminated by persistent organic pollutants (POPs). The objective of the present study was to evaluate the presence of polychlorinated biphenyl compounds (PCBs) in milk from dairy production units near sources of environmental pollutants. It was confirmed that the seven congeners of nondioxin-like PCBs (NDL-PCBs) are present in milk where compounds PCB101, PCB118, PCB153 and PCB180 appear in 100% of the samples analyzed, the rank of concentration for the sum of the seven congeners fluctuating between 2.6 and 26 ng g(-1) with a median of 6 ng g(-1). None of the samples surpassed the provisional value established by the EU of 40 ng g(-1) of milk fat for the sum of the seven congeners, indicator that was not affected by the season of the year (p<0.05), whose median of 8.6 ng g(-1) and 6.3 ng g(-1) for rain and drought respectively. The concentrations of NDL-PCBs found in milk do not represent a problem for human health; however, they alert the existence of spontaneously generated, uncontrolled sources that may represent a potential danger for human and animal health.

  14. 5-HT7 receptor modulators: Amino groups attached to biphenyl scaffold determine functional activity.

    Science.gov (United States)

    Kim, Youngjae; Park, Hyeri; Lee, Jeongeun; Tae, Jinsung; Kim, Hak Joong; Min, Sun-Joon; Rhim, Hyewhon; Choo, Hyunah

    2016-11-10

    5-HT7 receptor (5-HT7R) agonists and antagonists have been reported to be used for treatment of neuropathic pain and depression, respectively. In this study, as a novel scaffold for 5-HT7R modulators, we designed and prepared a series of biphenyl-3-yl-methanamine derivatives with various amino groups. Evaluation of functional activities as well as binding affinities of the title compounds identified partial agonists (EC50 = 0.55-3.2 μM) and full antagonists (IC50 = 5.57-23.1 μM) depending on the amino substituents. Molecular docking study suggested that the ligand-based switch in functional activity from agonist to antagonist results from the size of the amino groups and thereby different binding modes to 5-HT7R. In particular, interaction of the ligand with Arg367 of 5-HT7R is shown to differentiate agonists and antagonists. In the pharmacophore model study, two distinct pharmacophore models can tell whether a ligand is an agonist or an antagonist. Taken together, this study provides valuable information for designing novel compounds with selective agonistic or antagonistic properties against 5-HT7R.

  15. Biofilms at work: Bio-, phyto- and rhizoremediation approaches for soils contaminated with polychlorinated biphenyls

    Directory of Open Access Journals (Sweden)

    Merily Horwat

    2015-09-01

    Full Text Available Organohalide contaminants such as polychlorinated biphenyls (PCBs have been released into the environment for decades due to anthropogenic activities, but are also naturally produced in small amounts through volcanic eruptions and geochemical processes. Although toxic to humans and other organisms, the natural production of these compounds has resulted in the evolution of naturally occurring organohalide-respiring bacteria that possess the enzymes necessary to degrade PCB compounds to non-toxic products. The efficiency of PCB degradation can be improved by facilitating the formation of organohalide-respiring biofilms. During biofilm colonization on a surface or interface, bacteria are encased in an extracellular polymeric substance (EPS or “slime,” which allows them to share nutrients and remain protected from environmental stresses. Effective bioremediation of PCBs involves facilitation of biofilm growth to promote cooperation between bacteria, which can be further enhanced by the presence of certain plant species. This review aims to give an overview of biofilm processes involved in the detoxification of PCBs including anaerobic and aerobic PCB degradation by bacteria as well as the ability of plants to stimulate microbial activity and degradation (rhizoremediation and phytoremediation.

  16. Biodegradation of biphenyl and 2-chlorobiphenyl by a Pseudomonas sp. KM-04 isolated from PCBs-contaminated coal mine soil.

    Science.gov (United States)

    Nam, In-Hyun; Chon, Chul-Min; Jung, Ka-Young; Kim, Jae-Gon

    2014-07-01

    The biphenyl-degrading strain, Pseudomonas sp. KM-04, was isolated from polychlorinated biphenyls-contaminated soil sample obtained from the vicinity of a former coal mine. We herein report that strain KM-04 can use biphenyl as a sole carbon source, and resting cells convert biphenyl to its corresponding metabolic intermediates. Incubation of KM-04 with autoclaved mining-contaminated soil for 10 days in a slurry system reduced the levels of biphenyl and 2-chlorobiphenyl by 98.5 % and 82.3 %, respectively. Furthermore, treatment of a mine-soil microcosm with strain KM-04 for 15 days in a composting system under laboratory conditions reduced the levels of biphenyl and 2-chlorobiphenyl by 87.1 % and 68.7 %, respectively. These results suggest that KM-04 is a potential candidate for the biological removal of biphenyl and its chlorinated derivatives from polychlorinated biphenyl-contaminated mining areas.

  17. Plasma polychlorinated biphenyls in residents of 91 PCB-contaminated and 108 non-contaminated dwellings

    DEFF Research Database (Denmark)

    Meyer, Harald William; Frederiksen, Marie; Göen, Thomas;

    2013-01-01

    In the1950s-1970s polychlorinated biphenyls (PCBs) were used in several countries as plasticizers in elastic sealants in buildings.......In the1950s-1970s polychlorinated biphenyls (PCBs) were used in several countries as plasticizers in elastic sealants in buildings....

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

    Science.gov (United States)

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

    2013-11-26

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

  19. Molecular modeling and molecular dynamics simulation studies on the interactions of hydroxylated polychlorinated biphenyls with estrogen receptor-β.

    Science.gov (United States)

    Li, Xiaolin; Ye, Li; Wang, Xiaoxiang; Shi, Wei; Qian, XiangPing; Zhu, YongLiang; Yu, HongXia

    2013-10-01

    Endocrine-disrupting chemicals have attracted great concern. As major metabolites of polychlorinated biphenyls (PCBs), hydroxylated polychlorinated biphenyls (HO-PCBs) may disrupt estrogen hormone status because of their structural similarity to estrogen endogenous compounds. However, interactions between HO-PCBs and estrogen receptors (ERs) are not fully understood. In the present work, a molecular modeling study combining molecular docking, molecular dynamics simulations, and binding free energy calculations was performed to characterize the interactions of three HO-PCBs (4'-HO-PCB50, 2'-HO-PCB65, and 4'-HO-PCB69) having much different estrogenic activities with ERβ. Docking results showed that binding between ligands and ERβ was stabilized by hydrogen bond and hydrophobic interactions. The binding free energies of three ligands with ERβ were calculated, and further binding free energy decomposition analysis indicated that the dominating driving force of the binding between the ligands and ERβ was the van der Waals interaction. Some key residues, such as Leu298, Phe356, Gly472, His475, and Leu476, played important roles in ligand-receptor interactions by forming hydrophobic and hydrogen bond interactions with ligands. The results may be beneficial to increase understanding of the interactions between HO-PCBs and ERβ.

  20. 21 CFR 109.15 - Use of polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Use of polychlorinated biphenyls (PCB's) in... polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials. (a) Polychlorinated biphenyls (PCB's) represent a class of toxic industrial chemicals manufactured and sold under a variety...

  1. 21 CFR 509.15 - Use of polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Use of polychlorinated biphenyls (PCB's) in... polychlorinated biphenyls (PCB's) in establishments manufacturing food-packaging materials. (a) Polychlorinated biphenyls (PCB's) represent a class of toxic industrial chemicals manufactured and sold under a variety...

  2. 21 CFR 500.45 - Use of polychlorinated biphenyls (PCB's) in the production, handling, and storage of animal feed.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Use of polychlorinated biphenyls (PCB's) in the... GENERAL Specific Administrative Rulings and Decisions § 500.45 Use of polychlorinated biphenyls (PCB's) in the production, handling, and storage of animal feed. (a) Polychlorinated biphenyls (PCB's)...

  3. Determination of polychlorinated biphenyls, selected persistent organochlorine pesticides, and polybrominated flame retardants in fillets of fishes from the 2006 Missouri Department of Conservation Monitoring Programs

    Science.gov (United States)

    Gale, Robert W.; May, Thomas W.; Orazio, Carl E.; McKee, Michael J.

    2008-01-01

    This report presents the results of a study to determine polychlorinated biphenyl, organochlorine pesticide, and polybrominated diphenyl ether flame retardant concentrations in selected fishes from lakes and streams across Missouri. Fillets were collected from each fish sample, and after homogenization, compositing, and preparation, analyte concentrations were determined with dual column capillary gas chromatography-electron-capture detection. Total concentrations of polychlorinated biphenyls in samples ranged from background levels of about 20 to 1,200 nanograms per gram. Chlordanes and DDT-related chemicals constituted the primary classes of pesticides present at elevated concentrations in most samples, and ranged from 5 to 340 nanograms per gram. Total concentrations of polybrominated diphenyl ethers in samples ranged from background levels of about 5 to about 410 nanograms per gram. Concentrations of total technical chlordane ranged from less than 5 to 260 nanograms per gram. Concentrations of polychlorinated biphenyls, chlordanes, DDT-related compounds, and polybrominated diphenyl ethers were all greatest in samples of blue catfish from Cape Girardeau and Weldon Spring.

  4. Determination of polychlorinated biphenyls, selected persistent organochlorine pesticides, and polybrominated flame retardants in fillets of fishes from the 2007 Missouri Department of Conservation Monitoring Program

    Science.gov (United States)

    Gale, Robert W.; Orazio, Carl E.; McKee, Michael J.

    2009-01-01

    This report presents the results of a study to determine polychlorinated biphenyl, organochlorine pesticide, and polybrominated diphenylether flame retardant concentrations in selected fishes from lakes and streams across Missouri. Fillets were collected from each fish sample and after homogenization, compositing, and preparation, analyte concentrations were determined with dual column capillary gas chromatography-electron-capture detection. Total concentrations of polychlorinated biphenyls in samples ranged from background levels of about 50 to 300 nanograms per gram. In samples with elevated contaminant concentrations, chlordanes, DDT-related chemicals, and dieldrin constituted the primary classes of pesticides present, and ranged from 5 to 75 nanograms per gram. Total concentrations of polybrominated diphenyl ethers in samples ranged from background levels of 5 to 86 nanograms per gram. Channel catfish from the upper and lower Blue River and lake sturgeon from the Mississippi River at Saverton exhibited different polybrominated diphenyl ethers ratios. Concentrations of polychlorinated biphenyls, chlordanes, DDT-related compounds, and polybrominated diphenyl ethers all were greatest in samples of channel catfish from the upper and lower Blue River, and in samples of lake sturgeon from the Mississippi River at Saverton.

  5. Isolation and characteristics of a novel biphenyl-degrading bacterial strain, Dyella ginsengisoli LA-4

    Institute of Scientific and Technical Information of China (English)

    LI Ang; QU Yuanyuan; ZHOU Jiti; GOU Min

    2009-01-01

    A novel biphenyl-degrading bacterial strain LA-4 was isolated from activated sludge. It was identified as Dyella ginsengisoli according to phylogenetic similarity of 16S rRNA gene sequence. This isolate could utilize biphenyl as sole source of carbon and energy, which degraded over 95 mg/L biphenyl within 36 h. The major metabolites formed from biphenyl, such as 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid (HOPDA) and benzoic acid, were identified by LC-MS. The crude cell extract of strain LA-4 exhibited the activity of 2,3-dihydroxybiphenyl 1,2-dioxygenase (2,3-DHBD) and the kinetic parameters were Km= 26.48 μmol/L and Vmax= 8.12 μmol/mg protein. A conserved region of the biphenyl dioxygenase gene bphA1 of strain LA-4 was amplified by PCR and confirmed by DNA sequencing.

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

    Science.gov (United States)

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

    1999-01-01

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

  7. Organic compounds near dumpsites in Niagara Falls, New York.

    Science.gov (United States)

    Elder, V A; Proctor, B L; Hites, R A

    1981-09-01

    Water and sediment samples were taken from sites adjacent to hazardous waste disposal areas in Niagara Falls, New York. The samples were analyzed by gas chromatographic mass spectrometry. The following compounds were identified: chlorobenzenes, chlorotoluenes, polycyclic aromatic hydrocarbon derivatives, cyclohexane derivatives, polychlorinated biphenyls, trichlorophenol and other phenols, benzotrifluorides, mirex and phenothiazine. A large number of benzyl derivatives and unusual fluorinated compounds were also found; they were probably waste by-products of industrial chemical production. The hazardous waste disposal sites were probably the major sources for most of the compounds.

  8. Biphenyl synthase, a novel type III polyketide synthase.

    Science.gov (United States)

    Liu, B; Raeth, T; Beuerle, T; Beerhues, L

    2007-05-01

    Biphenyls and dibenzofurans are the phytoalexins of the Maloideae, a subfamily of the economically important Rosaceae. The carbon skeleton of the two classes of antimicrobial secondary metabolites is formed by biphenyl synthase (BIS). A cDNA encoding this key enzyme was cloned from yeast-extract-treated cell cultures of Sorbus aucuparia. BIS is a novel type III polyketide synthase (PKS) that shares about 60% amino acid sequence identity with other members of the enzyme superfamily. Its preferred starter substrate is benzoyl-CoA that undergoes iterative condensation with three molecules of malonyl-CoA to give 3,5-dihydroxybiphenyl via intramolecular aldol condensation. BIS did not accept CoA-linked cinnamic acids such as 4-coumaroyl-CoA. This substrate, however, was the preferential starter molecule for chalcone synthase (CHS) that was also cloned from S. aucuparia cell cultures. While BIS expression was rapidly, strongly and transiently induced by yeast extract treatment, CHS expression was not. In a phylogenetic tree, BIS grouped together closely with benzophenone synthase (BPS) that also uses benzoyl-CoA as starter molecule but cyclizes the common intermediate via intramolecular Claisen condensation. The molecular characterization of BIS thus contributes to the understanding of the functional diversity and evolution of type III PKSs.

  9. Levels of polychlorinated biphenyls in 1,4-dichlorobenzene mothballs

    Institute of Scientific and Technical Information of China (English)

    LIU Wen-bin; ZHENG Ming-hui; XING Ying; WANG Dong-sheng; ZHAO Xing-ru; GAO Li-rong

    2005-01-01

    Although polychlorinated biphenyls(PCBs) are globally recognized pollutant, an understanding of their resources as by-products in chemical industry is poorly investigated. This paper presents data from a study that was conducted in order to determine the extent of PCBs in 1,4-dichlorobenzene(p-DCB) mothballs. Total PCBs and dioxin-like PCBs were detected in five mothball samples. Total PCB concentrations ranged from 328 ng/g to 1798 ng/g, while the levels of WHO-TEQ were between 0.16 pg/g and 13 pg/g. Mean concentrations of total PCBs and WHO-TEQ in the samples were 724 ng/g and 3.2 pg/g, respectively. The highest level of PCB congeners was that of trichlorinated biphenyls(537 ng/g), which maybe due to the relatively low chlorination in the process of p-DCB production. A mechanism of the formation of PCBs from polychlorinated benzene in the presence of chlorine is also suggested. The results suggested that re-estimation on the risk of p-DCB products, especially the products for daily use such as mothballs, is expected.

  10. Studies on the Syntheses and Biological Activities of 3-Aryl-6-(1,1'-biphenyl-4-yl)-7H-1,2,4-triazolo[3,4-b][1,3,4]thiadiazines

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A series of novel 3-aryl-6-(1,1-biphenyl-4-yl)-7H-1,2,4-triazolo[3,4-b][1,3,4 ]thiadiazines was synthesized by means of the reactions between 3-aryl-4-amino-5-mercapto-1,2,4-triazoles and 2-bromo-4-phenylacetophenone. The structures of all the title compounds have been confirmed by virtue of elemental analysis, IR, 1H NMR, 13C NMR and mass spectra. The characteristics of 13C NMR peaks of the compounds were investigated. The plant growth regulating effects of those compounds were also determined.

  11. Decomposition of lignin model compounds by Lewis acid catalysts in water and ethanol

    NARCIS (Netherlands)

    Guvenatam, Burcu; Heeres, Erik H.J.; Pidko, Evgeny A.; Hensen, Emiel J. M.

    2015-01-01

    The conversion of benzyl phenyl ether, diphenyl ether, diphenyl methane and biphenyl as representative model compounds for alpha-O-4, 5-O-4, alpha(1) (methylene bridges) and 5-5' lignin linkages was investigated. We compared the use of metal chlorides and acetates. The reactions were studied in sub-

  12. Distribution of polychlorinated biphenyls, phthalic acid esters, polycyclic aromatic hydrocarbons and organochlorine substances in the Moscow River, Russia.

    Science.gov (United States)

    Eremina, Natalia; Paschke, Albrecht; Mazlova, Elena A; Schüürmann, Gerrit

    2016-03-01

    The purpose of this study was to investigate the levels of polychlorinated biphenyl (PCB), phthalic acid esters (PAE), polycyclic aromatic hydrocarbons (PAH) and organochlorine substances (OCP) in the Moscow River water. Some studies have reported the occurrence of these substances in the soil of the Moscow region; however, no study has yet established an overview for these compounds in the Moscow River water. In this study the Moscow River water contamination with PAEs, PAHs and OCPs was determined. Obtained results were associated with the resident area located on the river bank, and the possible contamination sources were considered. The obtained data were compared with the data on the contamination of the different world-wide rivers. This research indicates the further study necessity of the Moscow region to cover more contaminated sites and environmental compartments.

  13. Polychlorinated biphenyls and DDT in swordfish (Xiphias gladius) and blue shark (Prionace glauca) from Brazilian Coast. Preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Azevedo e Silva, C.E.; Azeredo, A.; Meire, R.; Torres, J.P. [Laboratorio de Radioisotopos E.P.F., Rio de Janeiro (Brazil). Inst. de Biofisica Carlos Chagas Filho, UFRJ; Brito Jr., J.L.; Malm, O. [Projeto Mamiferos Aquaticos, Rio de Janeiro (Brazil). Dept. de Oceanografia, UERJ

    2004-09-15

    There is conclusive evidence showing that, in general, fish in meals human diet contributes with a significant proportion of the total intake of PCBs and others organochlorine compounds, particularly fish with higher fat content. Thus, human exposure to PCBs is predominantly via diet, and especially from fish and seafood products. Comparatively, little is know about organochlorine contaminants in elasmobranch species, although they are also top predators. Characteristically, sharks are live longer, with comparatively slow rates of growth that in conjuction with their high trophic position may contribute to the accumulation of high concentrations of pollutants. Blue shark and swordfish are carnivorous fishes of great economic importance. This study investigate the concentration of polychlorinated biphenyls (PCBs) and DDTs in samples of muscle tissues of blue shark (Prionace glauca) and swordfish (Xiphias gladius) from Brazilian Coast.

  14. Determination of selected polychlorinated biphenyls in soil by miniaturised ultrasonic solvent extraction and gas chromatography-mass-selective detection.

    Science.gov (United States)

    Aydin, Mehmet Emin; Tor, Ali; Ozcan, Senar

    2006-09-08

    Miniaturised ultrasonic solvent extraction procedure was developed for the determination of selected polychlorinated biphenyls (PCBs) in soil samples by gas chromatography-mass-selective detection by using 2(3) factorial experimental design. Recoveries of PCBs from fortified soil samples are over 90% for three different fortification levels between 40 and 120 microg kg(-1), and relative standard deviations of the recoveries are below 7%. The limits of detection (LODs) ranged from 0.003 to 0.006 microg kg(-1). The performance of the proposed method was compared to traditional shake flask extraction method on the spiked real soil sample and extraction methods showed comparable efficiencies. Proposed miniaturised ultrasonic solvent extraction offers several advantages, i.e., reducing sample requirement for measurement of target compound, less solvent consumption and reducing the costs associated with solvent purchase and waste disposal.

  15. Bis(μ-diethyl sulfide-κ2S:Sbis[(biphenyl-2,2′-diylplatinum(ll

    Directory of Open Access Journals (Sweden)

    D. Paul Rillema

    2016-05-01

    Full Text Available The C4S2 donor set in the title compound, [Pt(C12H8{(C2H52S}]2, defines a distorted square-planar geometry about the two PtII atoms, with very small deviations from planarity. The bidentate nature of the biphenyl dianionic ligand results in C—Pt—C bond angles of 80.9 (2 and 81.2 (2°; the S—Pt—S bond angles are 78.08 (5 and 78.09 (5°. The average Pt—C bond length is 2.023 Å [range 2.016 (5–2.028 (6 Å] and the average of Pt—S bond length is 2.3790 Å [range 2.3742 (14–2.3837 (14 Å].

  16. (Biphenyl-2,2′-diyl[1,3-bis(diphenylphosphanylpropane-κ2P,P′]platinum(II

    Directory of Open Access Journals (Sweden)

    D. Paul Rillema

    2016-08-01

    Full Text Available The C2P2 donor set in the title compound, [Pt(C12H8(C27H26P2], defines a distorted planar coordination environment about the PtII atom with small deviations from planarity. The bidentate nature of the biphenyl dianionic ligand results in a C—Pt—C bond angle of 79.94 (16° and a P—Pt—P bond angle of 93.40 (4°. The average Pt—C bond length is 2.083 (3 Å [range 2.081 (4–2.085 (4 Å]; the average Pt—P bond length is 2.308 (8 Å [range 2.3030 (11–2.3136 (11 Å].

  17. Remobilization of polychlorinated biphenyls from sediment and its consequences for their transport in river waters.

    Science.gov (United States)

    Gdaniec-Pietryka, Monika; Mechlińska, Agata; Wolska, Lidia; Gałuszka, Agnieszka; Namieśnik, Jacek

    2013-05-01

    A laboratory experiment was performed to examine the remobilization of indicator polychlorinated biphenyls (iPCBs) from sediments and its results were applied to the real-world data for explaining the transport of PCBs in river. Seven PCB concentrations were determined in three series of model water-sediment systems (3 g of river sediment, three different volumes of distilled water (0.5, 0.25, and 0.15 ml), and 5 mg of biocide) after 11 days of incubation. Solid-phase extraction was used for separation of analytes from the aqueous phase and solvent extraction for isolation of analytes from the sediments, respectively. The extracts were analyzed for individual iPCB congeners using gas chromatography-mass spectrometry method. For each series of the experiment, the concentrations of PCBs in aqueous phase were similar. The average sediment/water partition coefficient value was 10(4) l/kg. The solubility of individual PCB congeners in water did not influence the desorption of PCBs from the sediment. Although the dominant form of PCBs in a water-sediment system occurs as suspended and colloidal fractions, these compounds are transported mostly in a dissolved form. Suspended and colloidal matter is a major sink for PCBs in low-energy aquatic environments. In contrast, the dissolved PCBs are readily transported in running waters. The mobilization of PCBs from sediments to aqueous phase, with respect to their solubility in water, seems to be limited, thus reducing the risk of secondary pollution.

  18. Trends in the enantiomeric composition of polychlorinated biphenyl atropisomers in human breast milk.

    Science.gov (United States)

    Konishi, Yoshimasa; Kakimoto, Kensaku; Nagayoshi, Haruna; Nakano, Takeshi

    2016-02-01

    For the precise estimation of the risk to human health caused by persistent organic pollutants (POPs), it is important to discuss enantiomer fraction value (EF value) because it is reported that behaviors such as stability and toxicity of enantiomers are quite different in human body. Among POPs, polychlorinated biphenyl (PCB) is known as one of the most persistent compounds in human breast milk samples. The main exposure source of PCB for human body is mostly from food especially in seafood. The contamination of fish and shellfish has been a serious problem for the Japanese, who consume a large amount of fish in their diet. PCBs have 19 congeners which are chlorine-substituted in 3- or 4- ortho positions are known to have enantiomers. In this study, we analyzed PCB 183 (2,2',3,4,4',5',6-hepta CB) in human breast milk and fish samples enantioselectively and revealed the time trends of the EF value. Though EF value of PCB 183 in fish samples sustained close to racemate (EF = 0.5) from 1982 to 2012, that in breast milk increased over time. This fact indicates that (+)-PCB-183 has greater bioaccumulation potential than (-)-PCB-183 in human body; therefore, the toxicity of (+)-PCB-183 should be emphasized.

  19. Assessment of atmospheric distribution of polychlorinated biphenyls and polycyclic aromatic hydrocarbons using polyparameter model

    Directory of Open Access Journals (Sweden)

    Turk-Sekulić Maja M.

    2011-01-01

    Full Text Available Results of partial or total destruction of industrial plants, military targets, infrastructure, uncontrolled fires and explosions during the conflict period from 1991 to 1999, at the area of Western Balkans, were large amounts of hazardous organic matter that have been generated and emitted in the environment. In order to assess gas/particle partition of seven EPA polychlorinated biphenyls and sixteen EPA polycyclic aromatic hydrocarbons, twenty air samples have been collected at six urban, industrial and highly contaminated localities in Vojvodina. Hi-Vol methodology has been used for collecting ambiental air samples, that simultaneously collects gaseous and particulate phase with polyurethane foam filters (PUF and glass fiber filters (GFF. PUF and GFF filters have been analyzed, and concentration levels of gaseous PCBs and PAHs molecules in gaseous and particulate phase were obtained, converted and expressed through fraction of individual compounds sorbed onto particulate phase of the sample, in total detected quantity. Experimentally gained gas/particle partitioning values of PCBs and PAHs molecules have been compared with PP-LFER model estimated values. Significant deviation has been noticed during comparative analysis of estimated polyparameter model values for complete set of seven PCBs congeners. Much better agreement of experimental and estimated values is for polycyclic aromatic hydrocarbons, especially for molecules with four rings. These results are in a good correlation with literature data where polyparameter model has been used for predicting gas/particle partition of studied group of organic molecules.

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

    Science.gov (United States)

    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.

  1. Bis(4-carbamoylpiperidinium biphenyl-4,4′-disulfonate

    Directory of Open Access Journals (Sweden)

    Graham Smith

    2010-12-01

    Full Text Available In the title isonipecotamide salt 2C6H13N2O+·C12H8O6S22−, the asymmetric unit comprises one biphenyl-4,4′-disulfonate dianion which lies across a crystallographic inversion centre and another in a general position [dihedral angle between the two phenyl rings is 37.1 (1°], together with three isonipecotamide cations. Two of these cations give a cyclic homomeric amide–amide dimer interaction [graph set R22(8], the other giving a similar dimeric interaction but across an inversion centre, both dimers then forming lateral cyclic R42(8 pyrimidinium–amide N—H...O interactions. These units are linked both laterally and longitudinally to the sulfonate groups of the dianions through piperidinium N—H...O hydrogen bonds, giving a three-dimensional framework structure.

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

    Science.gov (United States)

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

    2010-04-01

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

  3. Determination of polychlorinated biphenyls (PCBs) in insulating oil

    Energy Technology Data Exchange (ETDEWEB)

    Fujimoto, S.; Goda, Y.; Hirobe, M. [Japan EnvironChemicals Ltd., Tokyo (Japan); Tomita, J.; Nishikiori, M.; Nakajima, T. [Tokyo Electric Power Environmental Engineering Co. Inc., Tokyo (Japan); Rubio, F. [Abraxis LLC, Warminster, PA (United States); Takigami, H. [National Inst. for Environmental Studies, Tsukuba (Japan); Sakai, S. [Kyoto Univ., Kyoto (Japan); Ike, M.; Fujita, M. [Osaka Univ., Osaka (Japan)

    2005-07-01

    This paper described a newly developed cocktail polychlorinated biphenyl (PCB) enzyme-linked immunosorbent assay (ELISA) designed as a pretreatment method for determining levels of PCBs in insulating oils. Standard and pretreated PCBs were dissolved in dimethyl sulfoxide (DMSO) and mixed. The diluted mixture was then combined with a horseradish peroxidase conjugate combined with an anti-PCB antibody coupled with magnetic particles. A comparison of the method with standard ELISA processes indicated that the cocktail showed that cross reactivity patterns were improved. Twenty-six insulating oil samples contaminated with PCBs were then analyzed using the method. Values obtained using the cocktail method correlated with gas chromatography (GC) and mass spectroscopy (MS) analyses conducted on the same samples. It was concluded that the cocktail ELISA technique is a reliable and simple analytical method for determining PCBs in insulating oils. 3 refs., 4 tabs., 2 figs.

  4. Fluorescence characteristics of polychlorinated biphenyl isomers in cyclodextrin media

    Energy Technology Data Exchange (ETDEWEB)

    Femia, R.A.; Scypinski, S.; Love, L.J.C.

    1985-01-01

    The fluorescence characteristics of several polychlorinated biphenyl (PCB) isomers in ..cap alpha..- and ..beta..-cyclodextrin (CD) are discussed and contrasted. The steric hindrance of PCBs imposed by the positions of the chlorine atoms on the rings determines the overall stability of the resulting inclusion complexes with cyclodextrin which is reflected in the fluorescence intensities. Less substituted homologues include into the CD cavity equally well in both cyclodextrins, but very heavily substituted molecules show drastic differences between their fluorescence intensities in the ..cap alpha..- and ..beta..-cyclodextrin solutions. This behavior can be employed as a method for spectral fractionation of PCB isomers. Spectral separation is demonstrated here for two variably substituted molecules, and the photophysical limitations of this approach are discussed.

  5. Polychlorinated Biphenyls and Leukocyte Telomere Length: An Analysis of NHANES 1999-2002.

    Science.gov (United States)

    Scinicariello, Franco; Buser, Melanie C

    2015-12-01

    Polychlorinated biphenyls (PCBs) induce the expression of the proto-oncogene c-myc which has a role in cellular growth and proliferation programs. The c-myc up-regulates the telomerase reverse transcriptase which adds the telomeres repeating sequences to the chromosomal ends to compensate for the progressive loss of telomeric sequence. We performed multivariate linear regression to analyze the association of PCBs, polychlorinated dibenzo-p-dioxins, and 1,2,3,4,6,7,8-heptachlorodibenzofuran with leukocyte telomere length (LTL) in the adult population (n = 2413) of the National Health and Nutrition Examination Survey 1999-2002. LTL was natural log-transformed and the results were re-transformed and presented as percent differences. Individuals in the 3rd and 4th quartiles of the sum of PCBs were associated with 8.33% (95% CI: 4.08-13.88) and 11.63% (95% CI: 6.18-17.35) longer LTLs, respectively, compared with the lowest quartile, with evidence of a dose-response relationship (p-trend < 0.01). The association of the sum PCBs with longer LTL was found in both sexes. Additionally, 1,2,3,4,6,7,8-heptachlorodibenzofuran and 1,2,3,6,7,8-hexachlorodibenzo-p-dioxin were associated with longer LTL. The age independent association between longer LTL and environmental exposures to PCBs, 1,2,3,4,6,7,8-heptachlorodibenzofuran and 1,2,3,6,7,8-hexachlorodibenzo-p-dioxin may support a role as tumor promoter of these compounds. Further studies to evaluate the effect of these compounds on LTL are needed to more fully understand the implications of our finding.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  7. 78 FR 20640 - Polychlorinated Biphenyls (PCBs); Recycling Plastics from Shredder Residue

    Science.gov (United States)

    2013-04-05

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

  8. Uptake of polychlorinated biphenyls and organochlorine pesticides from soil and air into radishes (Raphanus sativus)

    DEFF Research Database (Denmark)

    Mikes, Ondrej; Cupr, P.; Trapp, Stefan

    2009-01-01

    Uptake of organochlorine pesticides and polychlorinated biphenyls from soil and air into radishes was measured at a heavily contaminated field site. The highest contaminant concentrations were found for DDT and its metabolites, and for beta-hexachlorocyclohexane. Bioconcentration factor (BCF...

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

    Science.gov (United States)

    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. Perinatal exposure to polychlorinated biphenyls and dioxins and its effect on neonatal neurological development

    NARCIS (Netherlands)

    Huisman, M.; Koopman-Esseboom, C.; Fidler, V.; Hadders-Algra, M.; Paauw, C.G. van der; Tuinstra, L.G.M.Th.; Weisglas-Kuperus, N.; Sauer, P.J.J.; Touwen, B.C.L.; Boersma, E.R.

    1995-01-01

    Polychlorinated biphenyls (PCBs) and dioxins (polychlorinated dibenzo-p-dioxins (PCDDs), and dibenzofurans (PCDFs)) are widespread environmental contaminants which are neurotoxic in animals. Perinatal exposure to PCBs, PCDDs, and PCDFs occurs prenatally via the placenta and postnatally via breast mi

  11. Biphenyl synthase from yeast-extract-treated cell cultures of Sorbus aucuparia.

    Science.gov (United States)

    Liu, Benye; Beuerle, Till; Klundt, Tim; Beerhues, Ludger

    2004-01-01

    Biphenyls and dibenzofurans are the phytoalexins of the Maloideae, a subfamily of the economically important Rosaceae. The biphenyl aucuparin accumulated in Sorbus aucuparia L. cell cultures in response to yeast extract treatment. Incubation of cell-free extracts from challenged cell cultures with benzoyl-CoA and malonyl-CoA led to the formation of 3,5-dihydroxybiphenyl. This reaction was catalysed by a novel polyketide synthase, which will be named biphenyl synthase. The most efficient starter substrate for the enzyme was benzoyl-CoA. Relatively high activity was also observed with 2-hydroxybenzoyl-CoA but, instead of the corresponding biphenyl, the derailment product 2-hydroxybenzoyltriacetic acid lactone was formed.

  12. PERINATAL EXPOSURE TO POLYCHLORINATED-BIPHENYLS AND DIOXINS AND ITS EFFECT ON NEONATAL NEUROLOGICAL DEVELOPMENT

    NARCIS (Netherlands)

    HUISMAN, M; KOOPMANESSEBOOM, C; FIDLER, [No Value; HADDERSALGRA, M; VANDERPAAUW, CG; TUINSTRA, LGMT; WEISGLASKUPERUS, N; SAUER, PJJ; TOUWEN, BCL; BOERSMA, ER

    1995-01-01

    Polychlorinated biphenyls (PCBs) and dioxins (polychlorinated dibenzo-p-dioxins (PCDDs), and dibenzofurans (PCDFs)) are widespread environmental contaminants which are neurotoxic in animals. Perinatal exposure to PCBs, PCDDs, and PCDFs occurs prenatally via the placenta and postnatally via breast mi

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

    DEFF Research Database (Denmark)

    Petersen, Maria Skaalum; Halling, Jónrit; Weihe, Pál

    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...

  14. Immunologic effects of background exposure to polychlorinated biphenyls and dioxins in Dutch preschool children

    NARCIS (Netherlands)

    N. Weisglas-Kuperus (Nynke); S. Patandin (Svati); G.A. Berbers; T.C.J. Sas (Theo); P.J.J. Sauer (Pieter); H. Hooijkaas (Herbert); P.G.H. Mulder (Paul)

    2000-01-01

    textabstractPrenatal exposure to polychlorinated biphenyls (PCBs) and dioxins is associated with changes in the T-cell lymphocyte population in healthy Dutch infants. We investigated whether these changes persist into later childhood and whether background exposure to P

  15. POLYCHLORINATED BIPHENYLS IN HOUSE DUST AND YARD SOIL NEAR A SUPERFUND SITE. (R825173)

    Science.gov (United States)

    Polychlorinated biphenyls (PCBs) were measured in house dust and yard soil at 34 homes surrounding New Bedford Harbor during dredging of highly contaminated harbor sediments. PCBs can volatilize from sediments and seawater and subsequently deposit on surrounding soil, resulting i...

  16. Polychlorinated biphenyl (PCB) removal from the Kenai National Wildlife Refuge, Alaska, October 1984 and 1988

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report covers the removal of polychlorinated biphenyl (PCB) from Kenai National Wildlife Refuge in Alaska during October 1984 and 1985. Atlantic Ritchfield...

  17. Effect of highly bioaccumulated polychlorinated biphenyl congeners on estrogen and androgen receptor activity

    DEFF Research Database (Denmark)

    Bonefeld-Jørgensen, E.C.; Andersen, H. R.; Rasmussen, T.H.;

    2001-01-01

    Polychlorinated biphenyls (PCBs) are ubiquitous environmental persistent contaminants giving rise to potential health hazard. Some PCBs exert dioxin-like activities mediated through the aryl hydrocarbon receptor. Although reports on interaction with other nuclear receptors are sparce, some...

  18. Biosynthesis of the biphenyl phytoalexin aucuparin in Sorbus aucuparia cell cultures treated with Venturia inaequalis.

    Science.gov (United States)

    Khalil, Mohammed N A; Beuerle, Till; Müller, Andreas; Ernst, Ludger; Bhavanam, Vijaya B R; Liu, Benye; Beerhues, Ludger

    2013-12-01

    Aucuparin is the most widely distributed biphenyl phytoalexin in the rosaceous subtribe Pyrinae, which includes the economically important fruit trees apple and pear. The biphenyl scaffold is formed by biphenyl synthase, which catalyzes biosynthesis of 3,5-dihydroxybiphenyl. Conversion of this precursor to aucuparin (3,5-dimethoxy-4-hydroxybiphenyl) was studied in cell cultures of Sorbus aucuparia after treatment with an elicitor preparation from the scab-causing fungus Venturia inaequalis. The sequence of the biosynthetic steps detected was O-methylation - 4-hydroxylation - O-methylation. The two alkylation reactions were catalyzed by distinct methyltransferases, which differed in pH and temperature optima as well as stability. Biphenyl 4-hydroxylase was a microsomal cytochrome P450 monooxygenase, whose activity was appreciably decreased by the addition of established P450 inhibitors. When fed to V. inaequalis-treated S. aucuparia cell cultures, radioactively labeled 3,5-dihydroxybiphenyl was not only incorporated into aucuparin but also into the dibenzofuran eriobofuran, the accumulation of which paralleled that of aucuparin. However, biphenyl 2'-hydroxylase activity proposed to be involved in dibenzofuran formation was detected in neither microsomes nor cell-free extracts in the presence of NADPH and 2-oxoglutarate, respectively. Nevertheless, a basis for studying biphenyl biosynthesis at the gene level is provided.

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

    Science.gov (United States)

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

    2005-02-01

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

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

    Directory of Open Access Journals (Sweden)

    Jianjun Shuai

    Full Text Available ABSTRACT 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.

  1. A Critical Review about Human Exposure to Polychlorinated Dibenzo-p-Dioxins (PCDDs), Polychlorinated Dibenzofurans (PCDFs) and Polychlorinated Biphenyls (PCBs) through Foods.

    Science.gov (United States)

    Fernández-González, R; Yebra-Pimentel, I; Martínez-Carballo, E; Simal-Gándara, J

    2015-01-01

    Dioxins include polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and part of polychlorinated biphenyls (PCBs). Only the compounds that are chlorinated at the 2,3,7, and 8 positions have characteristic dioxin toxicity. PCDDs, PCDFs and PCBs accumulate in the food chain due to their high lipophilicity, high stability, and low vapor pressure. They are not metabolized easily; however their hydroxylated metabolites are detected in feces. They cause a wide range of endocrine disrupting effects in experimental animals, wildlife, and humans. Endocrine related effects of PCDDs, PCDFs and PCBs on thyroid hormones, neurodevelopment and reproductive development were referenced. In addition, some studies of contamination of foods, bioaccumulation, dietary exposure assessment, as well as challenges of scientific research in these compounds were reviewed.

  2. The use of the DR CALUX bioassay and indicator polychlorinated biphenyls for screening of elevated levels of dioxins and dioxin-like polychlorinated biphenyls in eel.

    NARCIS (Netherlands)

    Hoogenboom, Ron; Bovee, Toine; Traag, Win A; Hoogerbrugge, Ronald; Baumann, Bert; Portier, Liza; Weg, Guido van de; Vries, Jaap de

    2006-01-01

    The DR CALUX bioassay is a very suitable screening method for dioxins and dioxin-like-PCBs in feed and food. This was, e. g. demonstrated in a survey in the Netherlands to control the dioxin levels in eel. The DR CALUX assay, but also indicator polychlorinated biphenyls (PCB) were evaluated as a scr

  3. Sulfate radical-based degradation of polychlorinated biphenyls: Effects of chloride ion and reaction kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Guo-Dong [Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100049 (China); Dionysiou, Dionysios D. [Environmental Engineering and Science Program, University of Cincinnati, Cincinnati, OH 45221-0071 (United States); Wang, Yu [Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100049 (China); Al-Abed, Souhail R. [National Risk Management Research Laboratory, U.S. Environmental Protection Agency, 26 West Martin Luther King Drive, Cincinnati, OH 45268 (United States); Zhou, Dong-Mei, E-mail: dmzhou@issas.ac.cn [Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China)

    2012-08-15

    Highlights: Black-Right-Pointing-Pointer A kinetic model was used to predict the radical species and their distributions. Black-Right-Pointing-Pointer The generated radical species were identified by EPR. Black-Right-Pointing-Pointer The second-order rate constants of sulfate radical with PCBs were determined. - Abstract: Advanced oxidation processes (AOPs) based on sulfate radical (SO{sub 4}{center_dot}{sup -}) have been recently used for soil and groundwater remediation. The presence of chloride ion in natural or wastewater decreases the reactivity of sulfate radical system, but explanations for this behavior were inconsistent, and the mechanisms are poorly understood. Therefore, in this paper we investigated the effect of chloride ion on the degradation of 2,4,4 Prime -CB (PCB28) and biphenyl (BP) by persulfate, based on the produced SO{sub 4}{center_dot}{sup -}. The results showed that the presence of chloride ion greatly inhibited the transformation of PCB28 and BP. Transformation intermediates of BP were monitored, suggesting that the chloride ion can react with SO{sub 4}{center_dot}{sup -} to produce chlorine radical, which reacts with BP to generate chlorinated compounds. To better understand the underlying mechanisms of these processes, a kinetic model was developed for predicting the effect of chloride ion on the types of radical species and their distributions. The results showed that chloride ion could influence the selectivity of radical species and their distribution, and increase the concentration of the sum of radical species. In addition, the second-order rate constants of sulfate radical with PCBs were determined, and quantum-chemical descriptors were introduced to predict the rate constants of other PCBs based on our experimental data.

  4. A cohort study of in utero polychlorinated biphenyl (PCB exposures in relation to secondary sex ratio

    Directory of Open Access Journals (Sweden)

    Keller Jean A

    2008-07-01

    Full Text Available Abstract Background Polychlorinated biphenyls (PCBs are ubiquitous industrial chemicals that persist in the environment and in human fatty tissue. PCBs are related to a class of compounds known as dioxins, specifically 2,3,7,8-TCDD (tetrachloro-dibenzodioxin, which has been implicated as a cause of altered sex ratio, especially in relation to paternal exposures. Methods In the 1960's, serum specimens were collected from pregnant women participating in the Child Health and Development Study in the San Francisco Bay Area. The women were interviewed and their serum samples stored at -20°C. For this study, samples were thawed and a total of eleven PCBs were determined in 399 specimens. Secondary sex ratio, or sex ratio at birth, was evaluated as a function of maternal serum concentrations using log-binomial and logistic regression, controlling for hormonally active medications taken during pregnancy. Results The relative risk of a male birth decreased by 33% comparing women at the 90th percentile of total PCBs with women at the 10th percentile (RR = 0.67; 95% CI, 0.48–0.94; p = 0.02, or by approximately 7% for each 1 μg/L increase in total PCB concentration. Although some congener-specific associations with sex ratio were only marginally statistically significant, all nine PCB congeners with Conclusion Maternal exposure to PCBs may be detrimental to the success of male sperm or to the survival of male embryos. Findings could be due to contaminants, metabolites or PCBs themselves.

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

    Science.gov (United States)

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

    2016-07-26

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

  6. Modeling polychlorinated biphenyl sorption isotherms for soot and coal

    Energy Technology Data Exchange (ETDEWEB)

    Jantunen, A.P.K.; Koelmans, A.A.; Jonker, M.T.O. [University of Utrecht, Utrecht (Netherlands)

    2010-08-15

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

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

    Science.gov (United States)

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

    2013-03-01

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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    Shin, Sun Kyoung; Kim, Tae Seung

    2006-10-11

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

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

    Science.gov (United States)

    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.

  11. Concentrations and patterns of hydroxylated polybrominated diphenyl ethers and polychlorinated biphenyls in arctic foxes (Vulpes lagopus) from Svalbard.

    Science.gov (United States)

    Routti, Heli; Andersen, Martin S; Fuglei, Eva; Polder, Anuschka; Yoccoz, Nigel G

    2016-09-01

    Concentrations and patterns of hydroxylated (OH) polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) were investigated in liver from arctic foxes (Vulpes lagopus) sampled from Svalbard 1997-2011 (n = 100). The most important OH-PBDE in the arctic foxes was 6-OH-BDE47 detected in 24% of the samples. Relationships between 6-OH-BDE47, δ(13)C and BDE47 suggest that 6-OH-BDE47 residues in arctic foxes are related to marine dietary input, while the relative importance of the metabolic/natural origin of this compound remains unclear. 4-OH-CB187 and 4-OH-CB146 were the main OH-PCBs among the analyzed compounds. The OH-PCB pattern in the present arctic foxes indicates that arctic foxes have a capacity to biotransform a wide range of PCBs of different structures. Formation and retention of OH-PCBs was tightly related to PCB exposure. Furthermore, ΣOH-PCB concentrations were four times higher in the leanest compared to the fattest foxes. Concentrations of 4-OH-CB187 and 4-OH-CB146 among the highest contaminated arctic foxes were similar to the previously reported concentrations for polar bears. Given the high endocrine disruptive potential of OH-PCBs, we suggest that endocrine system may be affected by the relatively high OH-PCB residues in the Svalbard arctic fox population.

  12. Grouping chemicals for health risk assessment: A text mining-based case study of polychlorinated biphenyls (PCBs).

    Science.gov (United States)

    Ali, Imran; Guo, Yufan; Silins, Ilona; Högberg, Johan; Stenius, Ulla; Korhonen, Anna

    2016-01-22

    As many chemicals act as carcinogens, chemical health risk assessment is critically important. A notoriously time consuming process, risk assessment could be greatly supported by classifying chemicals with similar toxicological profiles so that they can be assessed in groups rather than individually. We have previously developed a text mining (TM)-based tool that can automatically identify the mode of action (MOA) of a carcinogen based on the scientific evidence in literature, and it can measure the MOA similarity between chemicals on the basis of their literature profiles (Korhonen et al., 2009, 2012). A new version of the tool (2.0) was recently released and here we apply this tool for the first time to investigate and identify meaningful groups of chemicals for risk assessment. We used published literature on polychlorinated biphenyls (PCBs)-persistent, widely spread toxic organic compounds comprising of 209 different congeners. Although chemically similar, these compounds are heterogeneous in terms of MOA. We show that our TM tool, when applied to 1648 PubMed abstracts, produces a MOA profile for a subgroup of dioxin-like PCBs (DL-PCBs) which differs clearly from that for the rest of PCBs. This suggests that the tool could be used to effectively identify homogenous groups of chemicals and, when integrated in real-life risk assessment, could help and significantly improve the efficiency of the process.

  13. Combined effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin and polychlorinated biphenyls congeners in rats

    Energy Technology Data Exchange (ETDEWEB)

    Chu, I. [Environmental Science Bureau, Ottawa (Canada); Valli, V.E. [Coll. of Veterinary Medicine, Urbana (United States)

    2004-09-15

    There has been considerable interest in conducting toxicity studies on mixtures since this approach represents realistic human exposure and would provide a better model to predict the health impacts of environmental chemicals. However, risk assessment of the chemicals is largely based on the toxicity data of individual compounds by assuming simple additive effects of these compounds. This practice has been accepted by regulatory agencies provided that the concentrations of chemicals are extremely low, and there are no interactions. The existence of interactions among the chemicals co-administered to test animals may under or over estimate the effects of a mixture if the simple additive rule is applied. Previously, we demonstrated an antagonistic effect in rats when tetrachlorodibenzo-p-dioxin (TCDD) was co-administered with polychlorinated biphenyls congeners (PCBs). The hepatic microsomal EROD, MROD and UDPGT activities of TCDD were decreased when co-administered with PCB congeners. To further explore the combined effects of these pollutants, we examined and report results on tissue residue levels of TCDD and histopathological changes in target organs of rats exposed to TCDD, PCBs and mixtures of both.

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

    Science.gov (United States)

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

    2012-07-01

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

  15. Polybenzimidazole compounds

    Science.gov (United States)

    Klaehn, John R.; Peterson, Eric S.; Wertsching, Alan K.; Orme, Christopher J.; Luther, Thomas A.; Jones, Michael G.

    2010-08-10

    A PBI compound that includes imidazole nitrogens, at least a portion of which are substituted with an organic-inorganic hybrid moiety. At least 85% of the imidazole nitrogens may be substituted. The organic-inorganic hybrid moiety may be an organosilane moiety, for example, (R)Me.sub.2SiCH.sub.2--, where R is selected from among methyl, phenyl, vinyl, and allyl. The PBI compound may exhibit similar thermal properties in comparison to the unsubstituted PBI. The PBI compound may exhibit a solubility in an organic solvent greater than the solubility of the unsubstituted PBI. The PBI compound may be included in separatory media. A substituted PBI synthesis method may include providing a parent PBI in a less than 5 wt % solvent solution. Substituting may occur at about room temperature and/or at about atmospheric pressure. Substituting may use at least five equivalents in relation to the imidazole nitrogens to be substituted or, preferably, about fifteen equivalents.

  16. Recent advances in trifluoromethylation of organic compounds using Umemoto's reagents.

    Science.gov (United States)

    Zhang, Cai

    2014-09-14

    The incorporation of fluorine-containing moieties into organic compounds is of great importance in pharmaceutical, agricultural, and materials science. Within these organofluorides, the trifluoromethyl group is one of the most important motifs. In recent years, the trifluoromethyl group has attracted more and more attention, and many trifluoromethylated compounds have been found to possess special activities. However, until now, only a few methods have been developed to achieve this efficiently using Umemoto's reagents. This review highlights recent developments in the direct introduction of a trifluoromethyl group into organic compounds with Umemoto's reagents. Seven approaches to the trifluoromethylation of organic compounds are summarized: (i) trifluoromethylation of arenes, (ii) trifluoromethylation of alkenes, (iii) trifluoromethylation of terminal alkynes, (iv) deoxygenative trifluoromethylation of benzylic xanthates, (v) trifluoromethylation of ketoesters, (vi) trifluoromethylation of aryl boronic acids and aromatic amines (synthesis of ArCF3) and (vii) trifluoromethylation of biphenyl isocyanide derivatives.

  17. Nature of phenolic compounds in coffee melanoidins.

    Science.gov (United States)

    Coelho, Carina; Ribeiro, Miguel; Cruz, Ana C S; Domingues, M Rosário M; Coimbra, Manuel A; Bunzel, Mirko; Nunes, Fernando M

    2014-08-06

    Phenolic compounds are incorporated into coffee melanoidins during roasting mainly in condensed form (42-62 mmol/100 g) and also in ester-linked form (1.1-1.6 mmol/100 g), with incorporation levels depending on the green coffee chlorogenic acid content. The phenolic compounds are incorporated in different coffee melanoidin populations, but mainly in those soluble in 75% ethanol (82%), a significant correlation between the amount of phenolic compounds and the amount of protein and color characteristics of the different melanoidin populations being observed. The incorporation of phenolic compounds into coffee melanoidins is a significant pathway of chlorogenic acid degradation during roasting, representing 23% of the chlorogenic acids lost. These account for the nearly 26% of the material not accounted for by polysaccharides and proteins present in coffee melanodins. The cleavage mechanism and the efficiency of alkaline fusion used to release condensed phenolics from coffee melanoidins suggest that the phenolic compounds can be linked to the polymeric material by aryl-ether, stilbene type, and/or biphenyl linkages.

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

    Science.gov (United States)

    Henry, T B

    2015-01-01

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

  19. Immunotoxicity Monitoring in a Population Exposed to Polychlorinated Biphenyls

    Directory of Open Access Journals (Sweden)

    Hajo Haase

    2016-03-01

    Full Text Available 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.

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

    Science.gov (United States)

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

    2016-03-08

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

  1. Spermaturia and serum hormone concentrations at the age of puberty in boys prenatally exposed to polychlorinated biphenyls

    DEFF Research Database (Denmark)

    Mol, Nanette M; Sørensen, Nicolina; Weihe, Pal;

    2002-01-01

    To determine whether prenatal exposure to polychlorinated biphenyls (PCBs) with possible hormone-disrupting effects is capable of affecting sexual differentiation in boys at the age of puberty.......To determine whether prenatal exposure to polychlorinated biphenyls (PCBs) with possible hormone-disrupting effects is capable of affecting sexual differentiation in boys at the age of puberty....

  2. [Development of Self-assembled Dumbbell-like Fe3O4 Micro/nanomaterial for Application in Thermocatalytic Degradation of Polybrominated Biphenyls].

    Science.gov (United States)

    Huang, Xin-chen; Zong, Gang; Liu, Ye-xuan; Lu, Hui-jie; Li, Qian-qian; Li, Bin-ke; Zhao, Yan-hui; Su, Gui-jin

    2016-02-15

    Polybrominated biphenyls (PBBs) are a group of new persistent organic pollutants, which have high toxicity and long-term bioaccumulation, and cause potential risks to human beings and aquatic ecosystem. Self-assembled dumbbell-like Fe3O4 was synthesized via ethylene-glycol mediated method to degrade PBBs, using BB209 as a model compound. The results showed that the growth process of dumbbell-like Fe3O4 precursor had two stages involving a fast nucleation of amorphous primary particles followed by a slow aggregation and crystallization of primary particles. Dumbbell-like Fe3O4 showed high activity for degradation of BB209 at the reaction time of 30 min with the degradation efficiency of nearly 100% at 300 degrees C. A whole series of nonabromobiphenyl to monobromobiphenyl and biphenyls were detected as the degradation products of BB209 by dumbbell-like Fe3O4, indicating the occurrence of successive hydrodebromination reaction. Furthermore, the amounts of three NoBB isomers followed the order of BB207 > BB208 > BB206, indicating that the reactivity of C--Br of BB209 was in order of meta- > para- > ortho-positions.

  3. Analysis of polychlorinated dibenzo-p-dioxins, dibenzofurans and dioxin-like polychlorinated biphenyls in vegetable oil samples by gas chromatography-ion trap tandem mass spectrometry.

    Science.gov (United States)

    Malavia, J; Abalos, M; Santos, F J; Abad, E; Rivera, J; Galceran, M T

    2007-05-18

    Gas chromatography coupled to ion trap tandem mass spectrometry (CG-MS-MS) has been evaluated for the analysis of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dl-PCBs) in vegetable oil samples containing different concentration levels (0.2-6 pg WHO-TEQ g(-1) for both PCDD/Fs and dl-PCBs) of the 29 toxic congeners of PCDD/F and dioxin-like PCBs. The effect of potential interfering compounds such as polychlorinated naphthalenes (PCNs), polychlorinated biphenyls (PCBs) and polychlorinated diphenylethers (PCDEs) on the quantification of mono-ortho PCBs has been investigated. In addition, the influence of the clean-up procedure on the final determination by CG-MS-MS was studied, showing that the quality of the results depends to a great extent on this analytical step. Quality parameters have been established and good precisions (CV: 3-19%) and low limits of detection for PCDD/Fs (0.04-0.20 pg g(-1) oil) and dl-PCBs (0.08-0.64 pg g(-1) oil) were obtained. The method was validated by a comparison of the CG-MS-MS results with those obtained by GC-HRMS.

  4. Synthesis, radiosynthesis, in vitro and preliminary in vivo evaluation of biphenyl carboxylic and hydroxamic matrix metalloproteinase (MMP) inhibitors as potential tumor imaging agents

    Energy Technology Data Exchange (ETDEWEB)

    Oltenfreiter, Ruth [Laboratory of Radiopharmacy, Ghent University, Harelbekestraat 72, 9000 Ghent (Belgium)]. E-mail: ruth.oltenfreiter@ugent.be; Staelens, Ludovicus [Laboratory of Radiopharmacy, Ghent University, Harelbekestraat 72, 9000 Ghent (Belgium); Hillaert, Ulrik [Laboratory for Medicinal Chemistry, Ghent University, Harelbekestraat 72, 9000 Ghent (Belgium); Heremans, An; Noel, Agnes [Laboratory of Tumor and Developmental Biology, University of Liege, Sart-Tilman, Liege (Belgium); Frankenne, Francis [Laboratory of Tumor and Developmental Biology, University of Liege, Sart-Tilman, Liege (Belgium); Slegers, Guido [Laboratory of Radiopharmacy, Ghent University, Harelbekestraat 72, 9000 Ghent (Belgium)

    2005-06-01

    Excess matrix degradation is one of the hallmarks of cancer and is an important factor in the process of tumor progression. It is implicated in invasion, metastasis, growth, angiogenesis and migration. Many characteristics of matrix metalloproteinases (MMPs) make them attractive therapeutic and diagnostic targets. MMP expression is upregulated at the tumor site, with localization of activity in the tumor or the surrounding stroma, providing a target for medical imaging techniques. Radioiodinated carboxylic and hydroxamic MMP inhibitors 2-(4'-[{sup 123}I] iodo-biphenyl-4-sulfonylamino)-3-methyl-butyric acid (9) and 2-(4'-[{sup 123}I] iodo-biphenyl-4-sulfonylamino)-3-methyl-butyramide (11), their unlabelled standards and precursors were synthesized. Radioiodination was conducted by electrophilic aromatic substitution of the tributylstannyl precursors and resulted in radiochemical yields of 70+/-5% (n=6) and 60+/-5% (n=4), respectively. In vitro zymography and enzyme assays showed for both hydroxamic acid and carboxylic acid compounds a good inhibition activity and a high selectivity for MMP-2. In vivo biodistribution in NMRI mice showed no long-term accumulation in organs and the possibility to accumulate in the tumor in a later phase of this study.

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

    Science.gov (United States)

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

    2016-10-01

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

  6. NV- Polychlorinated biphenyls at Ash Meadows National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — PCBs or other organochlorine compounds were not detected in water from any site sampled during this study. Detection limits reported by the analytical laboratory...

  7. Multipurpose Compound

    Science.gov (United States)

    1983-01-01

    Specially formulated derivatives of an unusual basic compound known as Alcide may be the answer to effective treatment and prevention of the disease bovine mastitis, a bacterial inflammation of a cow's mammary gland that results in loss of milk production and in extreme cases, death. Manufactured by Alcide Corporation the Alcide compound has killed all tested bacteria, virus and fungi, shortly after contact, with minimal toxic effects on humans or animals. Alcide Corporation credits the existence of the mastitis treatment/prevention products to assistance provided the company by NERAC, Inc.

  8. Distribution of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in surface water and sediments from Baiyangdian Lake in North China

    Institute of Scientific and Technical Information of China (English)

    Guohua Dai; Xinhui Liu; Gang Liang; Xu Han; Liu Shi; Dengmiao Cheng; Wenwen Gong

    2011-01-01

    Persistent organochlorine compounds,including hexachlorocyclohexanes (HCHs),dichlorodiphenyltrichloroethanes (DDTs) and polychlorinated biphenyls (PCBs) were analyzed in surface water and sediments from Baiyangdian Lake,North China.Total concentrations of HCHs,DDTs and PCBs in surface water were in the range of 3.13-10.60,4.05-20.59 and 19.46-131.62 ng/L,respectively,and total concentrations of HCHs,DDTs and PCBs in sediments were 1.75-5.70,0.91-6.48 and 5.96-29.61 ng/g dry weight,respectively.Among the groups of HCHs (sum of α-HCH,β-HCH,γ-HCH and δ-HCH) and DDTs (sum of DDT,DDD and DDE),the predominance of β-HCH,DDE and DDD in water and sediment samples was clearly observed.This observation suggested that β-HCH was resistant to biodegradation and the DDTs had been transformed to its metabolites,DDE and DDD.For PCBs,penta-,hexa- and hepta-chlorinated congeners were the most abundant compounds in the both phases.Furthermore,the partitioning of chlorinated compounds between sediment and water was investigated to understand their transport and fates in aquatic ecosystems.The results indicated that average logs of organic carbon-normalized sediment-water partition coefficients (logK'∞) for OCPs varied between 3.20 and 5.53,and for PCBs,logK'∞ values ranged from 3.19 to 5.57.The observed logK'∞ was lower than their equilibrium logKoc predicted from linear model,which may be attributed to the solubility enhancement effect of colloidal matter in water phase and the disequilibrium between sediment and water.

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

    Energy Technology Data Exchange (ETDEWEB)

    Spector, June T., E-mail: spectj@uw.edu [Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, 4225 Roosevelt Way NE, Seattle, WA 98105 (United States); Department of Medicine, School of Medicine, University of Washington, Seattle, WA (United States); De Roos, Anneclaire J., E-mail: ajd335@drexel.edu [Epidemiology Program, Public Health Sciences Division, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue N, P.O. Box 19024, Seattle, WA 98109 (United States); Department of Epidemiology, School of Public Health, University of Washington, Seattle, WA (United States); Ulrich, Cornelia M., E-mail: neli.ulrich@nct-heidelberg.de [Department of Epidemiology, School of Public Health, University of Washington, Seattle, WA (United States); Cancer Prevention Program, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue N, P.O. Box 19024, Seattle, WA 98109 (United States); National Center for Tumor Diseases and German Cancer Research Center, Heidelberg (Germany); Sheppard, Lianne, E-mail: sheppard@uw.edu [Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, 4225 Roosevelt Way NE, Seattle, WA 98105 (United States); Department of Biostatistics, School of Public Health, University of Washington, Seattle, WA (United States); Sjoedin, Andreas, E-mail: asjodin@cdc.gov [National Center for Environmental Health, CDC, 4770 Buford Highway NE, Atlanta, GA 30341 (United States); Wener, Mark H., E-mail: wener@u.washington.edu [Department of Medicine, School of Medicine, University of Washington, Seattle, WA (United States); Wood, Brent, E-mail: woodbl@u.washington.edu [Department of Medicine, School of Medicine, University of Washington, Seattle, WA (United States); 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

  10. Lead, mercury, and organochlorine compound levels in cord blood in Québec, Canada.

    Science.gov (United States)

    Rhainds, M; Levallois, P; Dewailly, E; Ayotte, P

    1999-01-01

    We conducted this study to evaluate blood levels of lead, mercury, and organochlorine compounds in newborns in the Province of Quebec. During 1993 to 1995, we carried out a survey in 10 hospitals located in southern Quebec. During that time, umbilical cord blood samples were obtained from 1109 newborns, and we analyzed each for lead, mercury, 14 polychlorinated biphenyl congeners, and 11 chlorinated pesticides. We used the geometric mean and 95% confidence interval (CI) to describe the results. Mean concentrations of lead and mercury in cord blood were 0.076 micromol/l (95% CI = 0.074, 0.079) and 4.82 nmol/l (95% CI = 4.56, 5.08), respectively. The mean concentrations of total polychlorinated biphenyls (Aroclor 1260) and dichlorodiphenyl dichloroethylene were 0.514 microg/I (95% CI = .493, 0.536) and 0.412 microg/l (95% CI = 0.390, 0.435), respectively. We observed a statistically significant relationship between maternal age and cord blood concentrations of (a) lead, (b) mercury, (c) polychlorinated biphenyls, and (d) dichlorodiphenyl dichloroethylene. In addition, maternal smoking during pregnancy was associated with cord blood lead levels. The cord blood concentrations of lead, mercury, polychlorinated biphenyls, and dichlorodiphenyl dichloroethylene we measured in our study were the lowest levels recently reported in industrialized countries. The results of this study underline the role of public health authorities in the evaluation of biological levels of environmental contaminants among children for the assessment of risk of adverse health effects.

  11. Redefining the structure-activity relationships of 2,6-methano-3-benzazocines. Part 8. High affinity ligands for opioid receptors in the picomolar Ki range: oxygenated N-(2-[1,1'-biphenyl]-4-ylethyl) analogues of 8-CAC.

    Science.gov (United States)

    Wentland, Mark P; Jo, Sunjin; Gargano, Joseph M; VanAlstine, Melissa A; Cohen, Dana J; Bidlack, Jean M

    2012-12-15

    N-[2-(4'-methoxy[1,1'-biphenyl]-4-yl)ethyl]-8-CAC (1) is a high affinity (K(i)=0.084 nM) ligand for the μ opioid receptor and served as the lead compound for this study. Analogues of 1 were made in hopes of identifying an SAR within a series of oxygenated (distal) phenyl derivatives. A number of new analogues were made having single-digit pM affinity for the μ receptor. The most potent was the 3',4'-methylenedioxy analogue 18 (K(i)=1.6 pM).

  12. Polychlorinated biphenyls-induced alterations of thyroid hormone homeostasis and brain development in the rat.

    NARCIS (Netherlands)

    Morse, D.C.

    1995-01-01

    IntroductionThe work described in this thesis was undertaken to gain insight in the processes involved in the developmental neurotoxicity of polychlorinated biphenyls. It has been previously hypothesized that the alteration of thyroid hormone status by PCBs may be in part responsibl

  13. Differential effect of elicitors on biphenyl and dibenzofuran formation in Sorbus aucuparia cell cultures.

    Science.gov (United States)

    Hüttner, Cornelia; Beuerle, Till; Scharnhop, Helge; Ernst, Ludger; Beerhues, Ludger

    2010-11-24

    The Rosaceous subtribe Pyrinae (formerly subfamily Maloideae) is well-known for its economically important fruit trees, such as apple and pear, and also includes Sorbus aucuparia. Elicitor-treated S. aucuparia cell cultures are used to study the biosynthesis of the Pyrinae-specific phytoalexins, biphenyls and dibenzofurans. Three biphenyls (aucuparin, noraucuparin, 2'-hydroxyaucuparin) and a dibenzofuran (eriobofuran) were isolated and structure elucidated using GC-MS and NMR. A second dibenzofuran of low abundance was tentatively assigned as noreriobofuran. Treatment of S. aucuparia cell cultures with yeast extract induced the formation of aucuparin as the major phytoalexin. In contrast, addition of preparations from the fire blight bacterium, Erwinia amylovora, and the scab-causing fungus, Venturia inaequalis, resulted in accumulation of eriobofuran as the major inducible constituent. Methyl jasmonate was a poor elicitor. The observations are suggestive of a biogenic relationship between biphenyls and dibenzofurans. Elicitor-treated S. aucuparia cell cultures provide an interesting in vitro system for studying biphenyl and dibenzofuran metabolism in the economically valuable Pyrinae.

  14. Dermal toxicity studies of technical polychlorinated biphenyls and fractions thereof in rabbits

    NARCIS (Netherlands)

    Vos, J.G.; Beems, R.B.

    1971-01-01

    A significant difference in toxicity between 3 polychlorinated biphenyl (PCB) preparations was found in a prior study: Clophen A 60 and Phenoclor DP6 showing the highest, Aroclor 1260 the lowest, toxicity (Vos and Koeman, 1970). A subsequent study revealed the presence of tetra- and pentachlorodiben

  15. ESTIMATION OF GIBBS FREE-ENERGIES OF FORMATION FOR POLYCHLORINATED-BIPHENYLS

    NARCIS (Netherlands)

    HOLMES, DA; HARRISON, BK; DOLFING, J

    1993-01-01

    Gibbs free energies of formation for gas, subcooled liquid, and aqueous solution phases were estimated for all 209 polychlorinated biphenyl (PCB) congeners at 298.15 K and 100 000 Pa. A literature search was conducted to locate experimental data or predicted data for PCBs. Where other data were not

  16. New Biochemical Pathway for Biphenyl Degradation in Plants: Structural, Mechanistic and Biotechnological Aspects

    Energy Technology Data Exchange (ETDEWEB)

    Pacios, L. F.; Campos, V. M.; Merino, I.; Gomez, L.

    2009-07-01

    Polychlorinated biphenyls (PVBs) and other structurally-related xenobiotics are amongst the most relevant organic pollutants known today. while some bacterial species can metabolize PCBs, with varying efficiency, no catabolic pathways have yet been described in plants. This is so despite the great potential of (at least some) plant species for soil and groundwater decontamination, a technology known as phyto remediation. (Author)

  17. Immunologic effects of background exposure to polychlorinated biphenyls and dioxins in Dutch preschool children

    NARCIS (Netherlands)

    Weisglas-Kuperus, N; Patandin, S; Berbers, GAM; Sas, TCJ; Mulder, PGH; Sauer, PJJ; Hooijkaas, H

    2000-01-01

    Prenatal exposure to polychlorinated biphenyls (PCBs) and dioxins is associated with changes in the T-cell lymphocyte population in healthy Dutch infants. We investigated whether these changes persist into later childhood and whether background exposure to PCBs and dioxins is associated with the pre

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

    Science.gov (United States)

    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...

  19. Polychlorinated biphenyls in adipose tissue, liver, and brain from nine stillborns of varying gestational ages

    NARCIS (Netherlands)

    Huisman, M; Muskiet, FAJ; Van Der Paauw, CG; Essed, CE; Boersma, ER

    1998-01-01

    We analyzed polychlorinated biphenyls (PCBs) in s.c. adipose tissue, liver, and brain of nine fetuses who died in utero. Their median (range) gestational ages and birth weights were 34 (17-40) wk and 2050 (162-3225) g. Three fetuses were small for gestational age. The levels of PCB congener nos. 118

  20. Polychlorinated biphenyls alter expression of alpha-synuclein, synaptophysin and parkin in the rat brain

    DEFF Research Database (Denmark)

    Malkiewicz, Katarzyna; Mohammed, Roma; Folkesson, Ronnie;

    2006-01-01

    Polychlorinated Biphenyls (PCBs)-induced changes in synaptic transmission are one of the effects of their neurotoxicity but the mechanism remains unknown. We assessed the in vivo effects of the PCBs mixture, Aroclor 1254 on the expression of neuronal proteins that are involved in the synaptic...

  1. A method for the chemical modification of polychlorinated biphenyls for improved affinity towards noble metal surfaces

    DEFF Research Database (Denmark)

    2015-01-01

    The present application discloses a method for the modification and analysis of a field sample suspected of containing contaminant(s) like polychlorinated biphenyls (PCBs). The invention also relates to a corresponding kit for the modification of samples suspected of containing such contaminant(s)....

  2. Effects of sedimentary soot-like materials on bioaccumulation and sorption of polychlorinated biphenyls

    NARCIS (Netherlands)

    Jonker, M.T.O.; Hoenderboom, A.M.; Koelmans, A.A.

    2004-01-01

    Bioaccumulation of hydrophobic organic chemicals from sediments containing soot or sootlike materials has been hypothesized to be limited by strong sorption of the chemicals to the soot matrixes. To test this hypothesis, we quantified bioaccumulation of 11 polychlorinated biphenyls (PCBs) into the a

  3. (Biphenyl-2-alkyne) derivatives as common precursors for the synthesis of 9-iodo-10-organochalcogen-phenanthrenes and 9-organochalcogen-phenanthrenes.

    Science.gov (United States)

    Grimaldi, Tamiris B; Lutz, Guilherme; Back, Davi F; Zeni, Gilson

    2016-11-08

    In this paper, we report our results on the cyclization of (biphenyl-2-alkyne) derivatives to give two different types of phenanthrene derivatives, 9-iodo-10-organochalcogen-phenanthrenes and 9-organochalcogen-phenanthrenes. The strategy for the synthesis was based on the use of electrophilic cyclization for the preparation of 9-iodo-10-organochalcogen-phenanthrenes and iron(iii) chloride/diorganyl diselenide-mediated intramolecular cyclization to prepare 9-organochalcogen-phenanthrenes. The effects of solvent, temperature, reaction time and stoichiometry on the efficiency of cyclization reactions were investigated. The standard reaction conditions were compatible with many functional groups in the substrates, such as methyl, chlorine, fluorine and methoxyl. This protocol was efficient for diorganyl diselenides and disulfides but ineffective for diorganyl ditellurides. The resulting phenanthrenes were further functionalized through Sonogashira reactions followed by the electrophilic cyclization reaction to give the selenophene-fused aromatic compounds.

  4. Molecular dynamics and residual entropy in the soft crystal, SmE phase, of 4-butyl-4'-isothiocyano-1,1'-biphenyl.

    Science.gov (United States)

    Ishimaru, Shin'ichi; Saito, Kazuya; Ikeuchi, Satoaki; Massalska-Arodz, Maria; Witko, Waclaw

    2005-05-26

    Molecular dynamics and resulting disorder in the soft crystal, smectic E (SmE) phase, were studied in detail for the title compound, 4-butyl-4'-isothiocyano-1,1'-biphenyl (4TCB), by (1)H NMR spectroscopy and adiabatic calorimetry. The ordered crystal phase of 4TCB was realized for the first time under ambient pressure after long two-step annealing and used as the reference state in the analysis of the experimental results. Four motional modes were identified in the SmE phase through the analysis of the (1)H NMR T(1). The residual entropy was determined as ca. 6 J K(-1) mol(-1). This magnitude implies that most of the disorder in the SmE phase at high temperatures is removed on cooling except for the head-to-tail disorder of the rod-shaped 4TCB molecule. Standard thermodynamic functions are tabulated below 375 K.

  5. Feasibility of hydrofluoric acid etched sand particles for enrichment and determination of polychlorinated biphenyls at trace levels in environmental water samples.

    Science.gov (United States)

    Xing, Han-Zhu; Chen, Xiang-Feng; Wang, Xia; Wang, Ming-Lin; Zhao, Ru-Song

    2014-06-01

    This study aims to investigate the feasibility of etched sand particles being used as solid-phase extraction adsorbents to enrich polychlorinated biphenyls (PCBs), which are typical persistent organic pollutants in the environment, at trace levels. Gas chromatography-tandem mass spectrometry was selected to detect the compounds. Etched sand particles exhibited excellent merits on the enrichment of PCBs. Related important factors affecting extraction efficiencies were investigated and optimized in detail. Under optimized conditions, low limits of detection (0.42 to 3.69 ng L(-1)), wide linear range (10 to 1,000 ng L(-1)), and high repeatability (1.9 to 8.2%) were achieved. The developed method was validated with several real water samples, and satisfactory results were obtained. All of these findings indicate that etched sand particles would be useful for the enrichment and determination of organic pollutants at trace levels in water samples.

  6. The determination of the phase transition temperatures of a semifluorinated liquid crystalline biphenyl ester by impedance spectroscopy as an alternative method

    Science.gov (United States)

    Yıldız, Alptekin; Canli, Nimet Yilmaz; Karanlık, Gürkan; Ocak, Hale; Okutan, Mustafa; Eran, Belkız Bilgin

    2016-12-01

    Dielectric spectroscopy (DS) is a very powerful and important for better understanding of the molecular dynamics and relaxation phenomena in liquid crystals. The dielectric and impedance characteristics Ethyl 4-(7,7,8,8,9,9,10,10,10-nonafluorodecyloxy)biphenyl-4‧-carboxylate (ENBC) liquid crystal have been analyzed over the frequency range of 100 Hz to MHz in the temperature region from room temperature to 180 °C. The compound ENBC shows enantiotropic a smectic mesophase in a wide temperature range. The phase transition temperatures T (°C) of the liquid crystal ENBC, which were characterized by Differential Scanning Calorimetry (DSC), have been verified by the dielectric measurements and conductivity mechanisms of the ENBC. The activation energies for some selected angular frequencies have also been calculated.

  7. Bis(μ-diethyl sulfide-κ2S:S)bis[(biphenyl-2,2′-diyl)platinum(ll)

    OpenAIRE

    D. Paul Rillema; Curtis Moore; Ali Jehan

    2016-01-01

    The C4S2 donor set in the title compound, [Pt(C12H8){(C2H5)2S}]2, defines a distorted square-planar geometry about the two PtII atoms, with very small deviations from planarity. The bidentate nature of the biphenyl dianionic ligand results in C—Pt—C bond angles of 80.9 (2) and 81.2 (2)°; the S—Pt—S bond angles are 78.08 (5) and 78.09 (5)°. The average Pt—C bond length is 2.023 Å [range 2.016 (5)–2.028 (6) Å] and the average of Pt—S bond length is 2.3790 Å [range 2.3742 (14)–2.3837 (14) Å]....

  8. (Biphenyl-2,2′-diyl)[1,3-bis(diphenylphosphanyl)propane-κ2P,P′]platinum(II)

    OpenAIRE

    D. Paul Rillema; Curtis Moore; Ali Jehan

    2016-01-01

    The C2P2 donor set in the title compound, [Pt(C12H8)(C27H26P2)], defines a distorted planar coordination environment about the PtII atom with small deviations from planarity. The bidentate nature of the biphenyl dianionic ligand results in a C—Pt—C bond angle of 79.94 (16)° and a P—Pt—P bond angle of 93.40 (4)°. The average Pt—C bond length is 2.083 (3) Å [range 2.081 (4)–2.085 (4) Å]; the average Pt—P bond length is 2.308 (8) Å [range 2.3030 (11)–2.3136 (11) Å]....

  9. Concentrations of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in breast milk of women from Catalonia, Spain

    Energy Technology Data Exchange (ETDEWEB)

    Schuhmacher, M.; Domingo, L.L. [Lab. of Toxicology and Environmental Health (Spain); Kiviranta, H. [National Public Health Inst. (Finland); Vartiainen, T. [Univ. of Kuopio (Finland)

    2004-09-15

    Polychlorinated biphenyls (PCBs) are widely distributed environmental contaminants derived from their extensive use as coolants and lubricants in transformers, capacitors, and other electrical equipment. Polybrominated diphenyl ethers (PBDEs) are widely used as flame retardant in plastics, textiles and are also persistent organic pollutants (POPs). These compounds are lipophilic and difficult to metabolize. Therefore, environmental exposure of living organism results their accumulation in fat tissues via food. Although incineration has demonstrated to be a commercially available technology for hazardous waste (HW) disposal, the stack emission from HW incinerators (HWI) of a number of inorganic and organic substances has raised an important concern about the environmental and health consequences of this process of treating HW. In 1996, the construction of the first and to date only HWI in Spain was initiated in Constanti(Catalonia, Spain). Regular operations started in 1999. In order to establish the potential health risks of exposure on the general population living near the new HWI, a biological monitoring program was designed. To establish baseline levels of dioxins and furans (PCDD/Fs), and PCBs in human milk, samples were collected from women living in the neighborhood of the facility before starting regular operations. The purpose of the present study was to determine the concentrations of PCBs in breast milk of women living in the vicinity of the HWI after four years of regular operations in the facility. The levels of PBDEs were also measured.

  10. Comparison of five integrative samplers in laboratory for the monitoring of indicator and dioxin-like polychlorinated biphenyls in water.

    Science.gov (United States)

    Jacquet, Romain; Miège, Cécile; Smedes, Foppe; Tixier, Céline; Tronczynski, Jacek; Togola, Anne; Berho, Catherine; Valor, Ignacio; Llorca, Julio; Barillon, Bruno; Marchand, P; Coquery, Marina

    2014-03-01

    This study aimed at evaluating and comparing five integrative samplers for the monitoring of indicator and dioxin-like polychlorinated biphenyls (PCBs) in water: semi-permeable membrane device (SPMD), silicone rubber, low-density polyethylene (LDPE) strip, Chemcatcher and a continuous-flow integrative sampler (CFIS). These samplers were spiked with performance reference compounds (PRCs) and then simultaneously exposed under constant agitation and temperature in a 200 L stainless steel tank for periods ranging from one day to three months. A constant PCB concentration of about 1 ng·L(-1) was achieved by immersing a large amount of silicone rubber sheets ("dosing sheets") spiked with the target PCBs. The uptake of PCBs in the five samplers showed overall good repeatability and their accumulation was linear with time. The samplers SPMD, silicone rubber and LDPE strip were the most promising in terms of achieving low limits of quantification. Time-weighted average (TWA) concentrations of PCBs in water were estimated from uptake of PCBs using the sampling rates calculated from the release of PRCs. Except for Chemcatcher, a good agreement was found between the different samplers and TWA concentrations ranged between 0.4 and 2.8 times the nominal water concentration. Finally, the influence of calculation methods (sampler-water partition coefficients, selected PRCs, models) on final TWA concentrations was studied.

  11. Polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and perfluorinated alkylated substances (PFASs) in traditional seafood items from western Greenland.

    Science.gov (United States)

    Carlsson, Pernilla; Herzke, Dorte; Kallenborn, Roland

    2014-03-01

    In this study, contamination levels were determined for polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and perfluorinated alkylated substances (PFASs) in traditional Greenland seafood items, such as raw and smoked fish fillet (salmon and halibut), whale and seal meat and narwhal mattak (skin and blubber). The daily intake of PCBs, PBDEs and PFASs through traditional seafood items in Greenland was assessed. Based on the presented levels of contaminants, in combination with earlier food intake studies, suggests that the daily exposure was below the tolerable daily intake threshold for all compounds. BDE-47 was the only PBDE-congener detected in all food items, except in smoked halibut. The levels of BDE-47 varied from < LOD in smoked halibut up to 18 ng/g lw in narwhal mattak and 21 ng/g lw in whale beef. ∑PCB were lowest in smoked halibut (37 ng/g lw) and highest in narwhal mattak with 1,146 ng/g lw. Perfluorooctane sulfonate (PFOS) was the most common of the PFASs. However, ΣPFASs were below detection limits in most fish fillet samples, and varied from 2.9 ng/g ww in whale beef to 13.5 ng/g ww in seal beef. The present study shows that the exclusion from the diet of local food items such as intestines and blubber have a strong positive effect for the reduction of POPs levels in food, without a reducing the health benefits of traditional food intake considerably.

  12. A relevant exposure to a food matrix contaminated environmentally by polychlorinated biphenyls induces liver and brain disruption in rats.

    Science.gov (United States)

    Ounnas, Fayçal; Privé, Florence; Lamarche, Fréderic; Salen, Patricia; Favier-Hininger, Isabelle; Marchand, Philippe; Le Bizec, Bruno; Venisseau, Anais; Batandier, Cécile; Fontaine, Eric; de Lorgeril, Michel; Demeilliers, Christine

    2016-10-01

    Polychlorinated biphenyls (PCBs) are ubiquitous environmental contaminants present in dietary fats. Most studies evaluating PCB effects have been conducted with a single compound or a mixture of PCBs given as a single acute dose. The purpose of this study was to evaluate in vivo PCB toxicity in a realistic model of exposure: a low daily dose of PCBs (twice the tolerable daily intake (TDI)), chronically administered (8 weeks) to rats in contaminated goat milk. Liver and brain PCB toxicities were investigated by evaluating oxidative stress status and mitochondrial function. PCB toxicity in the liver was also estimated by transaminase enzymatic activity. This study shows that even at low doses, chronic PCB exposure resulted in a statistically significant reduction of mitochondrial function in liver and brain. In the liver, oxygen consumption in the condition of adenosine triphosphate (ATP) production (state 3) decreased by 22-29% (p < 0.01), according to the respiratory substrates. In the brain, respiratory chain complexes II and III were reduced by 24% and 39%, respectively (p < 0.005). The exposed rats presented higher lipid peroxidation status (+20%, p < 0.05) and transaminase activity (+30%, p < 0.05) in the blood. Thus, our study showed that exposure of rats to a daily realistic dose of PCBs (twice the TDI in a food complex mixture of environmental origin) resulted in multiple disruptions in the liver and brain.

  13. Polychlorinated biphenyls, organochlorine pesticides and trace metals in cultured and harvested bivalves from the eastern Adriatic coast (Croatia).

    Science.gov (United States)

    Milun, Vesna; Lušić, Jelena; Despalatović, Marija

    2016-06-01

    Polychlorinated biphenyls, organochlorine pesticides and trace metals were determined in tissues of bivalve molluscs (Mytilus galloprovincialis, Ostrea edulis, Venus verrucosa, Arca noae and Callista chione), collected from 11 harvesting and 2 cultured locations along the eastern Adriatic coast, in May and November 2012. Concentrations (ng g(-1) dry weight) of organochlorines ranged from 1.53 to 21.1 for PCBs and 0.68 to 5.21 for p,p'-DDTs. HCB, lindane, heptachlor and aldrin-like compounds were found in lower levels or were not detected. Metal concentrations (mg kg(-1) dry weight) ranged from 0.23 to 4.03 for Cd, 0.87-3.43 for Cr, 3.69-202.3 for Cu, 0.06-0.26 for HgT, 0.62-9.42 for Ni, 0.95-4.64 for Pb, and 55.76-4010.3 for Zn. Established organochlorine and trace metal levels were lower than the maximum allowable levels in seafood set by the European Commission.

  14. Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in harbor sediments from Sea Lots, Port-of-Spain, Trinidad and Tobago

    Science.gov (United States)

    Mohammed, Azad; Peterman, Paul; Echols, Kathy; Feltz, Kevin; Tegerdine, George; Manoo, Anton; Maraj, Dexter; Agard, John; Orazio, Carl

    2011-01-01

    Concentrations of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were determined in nearshore marine surficial sediments from three locations in Trinidad. Sediments were sampled at Sea Lots on the west coast, in south Port-of-Spain Harbor, south of Sea Lots at Caroni Lagoon National Park, and on Trinidad's east coast at Manzanilla. Total PCB concentrations in Sea Lots sediments ranged from 62 to 601 ng/g (dry weight {dw}), which was higher than at Caroni and Manzanilla, 13 and 8 ng/g dw, respectively. Total OCP concentrations at Sea Lots were ranged from 44.5 to 145 ng/g dw, compared with 13.1 and 23.8 n/g (dw), for Caroni and Manzanilla respectively. The concentrations of PCBs and of some OCPs in sediments from Sea Lots were above the Canadian interim sediment quality guidelines. To date, this data is the first report on the levels of PCBs and other organochlorine compounds from Trinidad and Tobago.

  15. Retention modelling of polychlorinated biphenyls in comprehensive two-dimensional gas chromatography.

    Science.gov (United States)

    D'Archivio, Angelo Antonio; Incani, Angela; Ruggieri, Fabrizio

    2011-01-01

    In this paper, we use a quantitative structure-retention relationship (QSRR) method to predict the retention times of polychlorinated biphenyls (PCBs) in comprehensive two-dimensional gas chromatography (GC×GC). We analyse the GC×GC retention data taken from the literature by comparing predictive capability of different regression methods. The various models are generated using 70 out of 209 PCB congeners in the calibration stage, while their predictive performance is evaluated on the remaining 139 compounds. The two-dimensional chromatogram is initially estimated by separately modelling retention times of PCBs in the first and in the second column ((1) t (R) and (2) t (R), respectively). In particular, multilinear regression (MLR) combined with genetic algorithm (GA) variable selection is performed to extract two small subsets of predictors for (1) t (R) and (2) t (R) from a large set of theoretical molecular descriptors provided by the popular software Dragon, which after removal of highly correlated or almost constant variables consists of 237 structure-related quantities. Based on GA-MLR analysis, a four-dimensional and a five-dimensional relationship modelling (1) t (R) and (2) t (R), respectively, are identified. Single-response partial least square (PLS-1) regression is alternatively applied to independently model (1) t (R) and (2) t (R) without the need for preliminary GA variable selection. Further, we explore the possibility of predicting the two-dimensional chromatogram of PCBs in a single calibration procedure by using a two-response PLS (PLS-2) model or a feed-forward artificial neural network (ANN) with two output neurons. In the first case, regression is carried out on the full set of 237 descriptors, while the variables previously selected by GA-MLR are initially considered as ANN inputs and subjected to a sensitivity analysis to remove the redundant ones. Results show PLS-1 regression exhibits a noticeably better descriptive and predictive

  16. Predicting the bioaccumulation of polyaromatic hydrocarbons and polychlorinated biphenyls in benthic animals in sediments

    Energy Technology Data Exchange (ETDEWEB)

    Tuikka, A.I., E-mail: anitat@student.uef.fi [University of Eastern Finland, Department of Environmental and Biological Sciences, P.O. Box 111, FI-80101 Joensuu (Finland); Leppänen, M.T., E-mail: Matti.T.Leppanen@ymparisto.fi [Finnish Environment Institute, Laboratories/Research and Innovation Laboratory, P.O. Box 35, University of Jyväskylä, FI-40014 Jyväskylä (Finland); Akkanen, J., E-mail: jarkko.akkanen@uef.fi [University of Eastern Finland, Department of Environmental and Biological Sciences, P.O. Box 111, FI-80101 Joensuu (Finland); Sormunen, A.J., E-mail: Arto.Sormunen@mamk.fi [University of Eastern Finland, Department of Environmental and Biological Sciences, P.O. Box 111, FI-80101 Joensuu (Finland); Leonards, P.E.G., E-mail: pim.leonards@vu.nl [Institute for Environmental Studies, Vrije Universiteit Amsterdam, De Boelelaan 1087, 1081 HV Amsterdam (Netherlands); Hattum, B. van, E-mail: bert.vanhattum@deltares.nl [Institute for Environmental Studies, Vrije Universiteit Amsterdam, De Boelelaan 1087, 1081 HV Amsterdam (Netherlands); Vliet, L.A. van, E-mail: lavanvliet@hotmail.com [Ministry of Transport, Public Works and Water Management, National Institute for Coastal and Marine Management/RIKZ, P.O. Box 207, 9750 AE Haren (Netherlands); Brack, W., E-mail: werner.brack@ufz.de [Helmholtz Centre for Environmental Research - UFZ, Department of Effect-Directed Analysis, Permoserstraße 15, 04318 Leipzig (Germany); Smedes, F., E-mail: smedes@recetox.muni.cz [Ministry of Transport, Public Works and Water Management, National Institute for Coastal and Marine Management/RIKZ, P.O. Box 207, 9750 AE Haren (Netherlands); and others

    2016-09-01

    There were two main objectives in this study. The first was to compare the accuracy of different prediction methods for the chemical concentrations of polyaromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in the organism, based on the measured chemical concentrations existing in sediment dry matter or pore water. The predicted tissue concentrations were compared to the measured ones after 28-day laboratory test using oligochaeta worms (Lumbriculus variegatus). The second objective was to compare the bioaccumulation of PAHs and PCBs in the laboratory test with the in situ bioaccumulation of these compounds. Using the traditional organic carbon-water partitioning model, tissue concentrations were greatly overestimated, based on the concentrations in the sediment dry matter. Use of an additional correction factor for black carbon with a two-carbon model, significantly improved the bioaccumulation predictions, thus confirming that black carbon was important in binding the chemicals and reducing their accumulation. The predicted PAH tissue concentrations were, however, high compared to the observed values. The chemical concentrations were most accurately predicted from their freely dissolved pore water concentrations, determined using equilibrium passive sampling. The patterns of PCB and PAH accumulation in sediments for laboratory-exposed L. variegatus were similar to those in field-collected Lumbriculidae worms. Field-collected benthic invertebrates and L. variegatus accumulated less PAHs than PCBs with similar lipophilicity. The biota to sediment accumulation factors of PAHs tended to decrease with increasing sediment organic carbon normalized concentrations. The presented data yields bioconcentration factors (BCF) describing the chemical water-lipid partition, which were found to be higher than the octanol-water partition coefficients, but on a similar level with BCFs drawn from relevant literature. In conclusion, using the two-carbon model method

  17. Intermetallic Compounds

    Science.gov (United States)

    Takagiwa, Y.; Matsuura, Y.; Kimura, K.

    2014-06-01

    We have focused on the binary narrow-bandgap intermetallic compounds FeGa3 and RuGa3 as thermoelectric materials. Their crystal structure is FeGa3-type (tetragonal, P42/ mnm) with 16 atoms per unit cell. Despite their simple crystal structure, their room temperature thermal conductivity is in the range 4-5-W-m-1-K-1. Both compounds have narrow-bandgaps of approximately 0.3-eV near the Fermi level. Because their Seebeck coefficients are quite large negative values in the range 350-FeGa3 and RuGa3 as n and p-type materials. The dimensionless figure of merit, ZT, was significantly improved by substitution of Sn for Ga in FeGa3 (electron-doping) and by substitution of Zn for Ga in RuGa3 (hole-doping), mainly as a result of optimization of the electronic part, S 2 σ.

  18. Compound odontoma

    Directory of Open Access Journals (Sweden)

    Monica Yadav

    2012-01-01

    Full Text Available Odontomas have been extensively reported in the dental literature, and the term refers to tumors of odontogenic origin. Though the exact etiology is still unknown, the postulated causes include: local trauma, infection, inheritance and genetic mutation. The majority of the lesions are asymptomatic; however, may be accompanied with pain and swelling as secondary complaints in some cases. Here, we report a case of a compound odontome in a 14 year old patient.

  19. Organic Compounds

    Science.gov (United States)

    Shankland, Kenneth

    For many years, powder X-ray diffraction was used primarily as a fingerprinting method for phase identification in the context of molecular organic materials. In the early 1990s, with only a few notable exceptions, structures of even moderate complexity were not solvable from PXRD data alone. Global optimisation methods and highly-modified direct methods have transformed this situation by specifically exploiting some well-known properties of molecular compounds. This chapter will consider some of these properties.

  20. Concentrations of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and dioxin-like polychlorinated biphenyls in blood collected from 195 pregnant women in Sapporo City, Japan.

    Science.gov (United States)

    Todaka, Takashi; Hirakawa, Hironori; Kajiwara, Jumboku; Hori, Tsuguhide; Tobiishi, Kazuhiro; Onozuka, Daisuke; Kato, Shizue; Sasaki, Seiko; Nakajima, Sonomi; Saijo, Yasuaki; Sata, Fumihiro; Kishi, Reiko; Iida, Takao; Furue, Masutaka

    2007-10-01

    We measured the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), non-ortho coplanar polychlorinated biphenyls (non-ortho PCBs), and mono-ortho coplanar polychlorinated biphenyls (mono-ortho PCBs) in blood collected between 2002 and 2004 from 195 pregnant women living in Sapporo City of Hokkaido Prefecture, Japan. The present study is one of the few studies in which PCDDs, PCDFs, and dioxin-like PCBs have been measured in the blood of pregnant women. Of the 195 pregnant women, 101 were primipara (mean: 28.8 years) and 94 were multipara (mean: 32.4 years). The arithmetic mean total TEQ concentrations of PCDDs, PCDFs, non-ortho PCBs, and mono-ortho PCBs of primiparous and multiparous mothers in Sapporo City were 17.4 (median: 15.7) and 14.0 (median: 13.9)pgTEQ/glipid, respectively, and the concentrations were in the range of 6.6-43.4 and 3.4-28.2pgTEQ/glipid, respectively. In regard to the relationship between the total TEQ concentrations of PCDDs, PCDFs, non-ortho PCBs, and mono-ortho PCBs in maternal blood and the number of deliveries or age of primiparous and multiparius mothers, the levels of these dioxin-like compounds tended to decrease with increases in the number of deliveries and significantly increased with increasing maternal age in both groups. Furthermore, significant correlations were observed between the total TEQ concentrations of these dioxin-like compounds and the age of primiparae and multiparae. The total TEQ concentration of PCDDs, PCDFs, non-ortho PCBs, and mono-ortho PCBs measured in 195 pregnant women has decreased compared to past levels in Japan for the last several decades. The results of the present study have indicated that dioxin contamination in the blood of young women in Japan is continuing to decrease.

  1. [Recent advances in Sphingobium sp. SYK-6 for lignin aromatic compounds degradation--a review].

    Science.gov (United States)

    Zhang, Xiaoyan; Peng, Xue; Masai, Eiji

    2014-08-01

    Lignin is complex heteropolymer produced from hydroxycinnamyl alcohols through radical coupling. In nature, white-rot fungi are assumed initially to attack native lignin and release lignin-derived-low-molecular-weight compounds, and soil bacteria play an importent role for completely degradation of these compounds. Study on the soil bacteria degrading lignin-derived-low-molecular-weight compounds will give way to understand how aromatic compounds recycle in nature, and to utilize lignin compounds as the renewable materials for valuable materials production. Sphingobium sp. SYK-6 that grows on lignin biphenyl (5,5'-dehydrodivanillate) had been isolated from pulp effluent in 1987. We have researched this bacterium more than 25 years, a serious aromatic metabolic pathway has been determined, and related genes have been isolated. As the complete genome sequence of SYK-6 has been opened to the public in 2012, the entire aromatic compounds degradation mechanisms become more clear. Main contents in our review cover: (1) genome information; (2) aryl metabolism; (3) biphenyl metabolism; (4) ferulate metabolism; (5) tetrahydrofolate-dependent O-demethylation system for lignin compound degrdation; (6) protocatechuate 4,5-cleavage pathway; (7) multiple pathways for 3-O-methylgallate metabolism.

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

    Science.gov (United States)

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

    2001-01-01

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

  3. A Review on Polychlorinated Biphenyls (PCBs) and Polybrominated Diphenyl Ethers (PBDEs) in South Asia with a Focus on Malaysia.

    Science.gov (United States)

    Kaw, Han Yeong; Kannan, Narayanan

    2017-01-01

    Malaysia is a developing country in Southeast Asia, with rapid industrial and economic growth. Speedy population growth and aggressive consumerism in the past five decades have resulted in environmental pollution issues, including products containing polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). PCBs and PBDEs are classified as persistent organic pollutants (POPs) by the Stockholm Convention due to their persistence, bioaccumulation in the environment and toxicity to humans and wildlife. These compounds are known to cause liver dysfunction, thyroid toxicity, developmental neuro-toxicity and possibly cancer. PCBs in air, mussels, pellets, seawater, fresh water, and human breast milk samples were analyzed in Malaysia, while studies on the pollution level of PBDEs in Malaysia were conducted on mussels, soils, leachate and sediment samples. PCBs in breast milk collected from Malaysia was the highest among Asian developing countries, with mean concentration of 80 ng/g lipid weight. On the other hand, the mean concentration of PCBs in mussels collected from Malaysia recorded the second lowest, with 56 ng/g and 89 ng/g lipid weight in two studies respectively. The concentrations of PBDEs in mussels taken from Malaysia fall in the range of 0.84-16 ng/g lipid weight, which is considerably low compared to 104.5 ng/g lipid weight in Philippines and 90.59 ng/g in Korea. Nevertheless, there are limited studies on these compounds in Malaysia, particularly there is no research on PBDEs in breast milk and sediment samples. This review will summarize the contamination levels of PCBs and PBDEs in different samples collected from Asian countries since 1988 until 2010 with a focus on Malaysia and will provide needed information for further research in this field.

  4. Chlorinated organic compounds in urban river sediments

    Energy Technology Data Exchange (ETDEWEB)

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

    1995-12-31

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

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

    Science.gov (United States)

    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...

  6. Mixed function oxidase dependent biotransformation of polychlorinated biphenyls by different species of fish from the North Sea

    DEFF Research Database (Denmark)

    Mehrtens, G.; Laturnus, F.

    1999-01-01

    Mixed function oxidase (MFO) dependent biotransformation of polychlorinated biphenyls (PCBs) was measured in three different fish species from the North Sea. Liver microsomes of plaice (Pleuronectes platessa), dab (Limanda limanda) and cod (Gadus morhua) were isolated and incubated with different...

  7. Magnesium compounds

    Science.gov (United States)

    Kramer, D.A.

    2012-01-01

    Seawater and natural brines accounted for about 57 percent of magnesium compounds produced in the United States in 2011. Dead-burned magnesia was produced by Martin Marietta Magnesia Specialties LLC from well brines in Michigan. Caustic-calcined magnesia was recovered from seawater by Premier Magnesia LLC in Florida, from well brines in Michigan by Martin Marietta and from magnesite in Nevada by Premier Magnesia. Intrepid Potash Wendover LLC and Great Salt Lake Minerals Corp. recovered magnesium chloride brines from the Great Salt Lake in Utah. Magnesium hydroxide was produced from seawater by SPI Pharma Inc. in Delaware and Premier Magnesia in Florida, and by Martin Marietta from its brine operation in Michigan.

  8. Design and synthesis of ten biphenyl-neolignan derivatives and their in vitro inhibitory potency against cyclooxygenase-1/2 activity and 5-lipoxygenase-mediated LTB4-formation.

    Science.gov (United States)

    Schühly, Wolfgang; Hüfner, Antje; Pferschy-Wenzig, Eva M; Prettner, Elke; Adams, Michael; Bodensieck, Antje; Kunert, Olaf; Oluwemimo, Asije; Haslinger, Ernst; Bauer, Rudolf

    2009-07-01

    A set of ten derivatives of methylhonokiol, an anti-inflammatory active biphenyl-type neolignan from Magnolia grandiflora, has been evaluated for their in vitro cyclooxygenase-1/2 (COX-1/2) inhibitory activity using assays with purified prostaglandin H synthase (PGHS)-1 and PGHS-2 enzymes as well as for their 5-lipoxygenase (5-LOX) mediated LTB(4) formation inhibitory activity using an assay with activated human polymorphonuclear leukocytes. The derivatization reactions included methylation, acetylation, hydrogenation, epoxydation and isomerization. Five of the derivatives are new to science. The most active compound against COX-1 and COX-2 was methylhonokiol with IC(50) values of 0.1 microM, whereas the most active compound against LTB(4) formation was (E)-3'-propenyl-5-(2-propenyl)-biphenyl-2,4'-diol with an IC(50) value of 1.0 microM. Structure-activity relationship studies showed that the polarity of the derivatives plays a crucial role in their activity towards COX-1/2 enzyme and 5-LOX mediated LTB(4) formation.

  9. Quercetin ameliorates polychlorinated biphenyls-induced testicular DNA damage in rats.

    Science.gov (United States)

    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 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.

  10. Reducing ulcerogenic potential of biphenyl acetic acid: Design and development of chimeric derivatives with amino acids

    Directory of Open Access Journals (Sweden)

    Suneela Dhaneshwar

    2016-09-01

    Full Text Available In an attempt to minimize the ulcerogenic potential and associated gastro-intestinal toxicity of bioprecursor fenbufen and its active metabolite biphenyl acetic acid, carrier-linked chimeric derivatives of the latter were designed and synthesized using amino acids as the promoities. DCC coupling method was used for the synthesis of these amides. The chimeras were characterized by IR and 1H NMR. Pharmacological investigations were carried out in animal models for analgesic, anti-inflammatory, anti-arthritic and ulcerogenic activities. The chimeras exhibited high gastro-sparing effect; quick onset and longer duration of analgesia; enhanced/prolonged anti-inflammatory activity and better anti-arthritic effect than fenbufen or biphenyl acetic acid. These derivatives could be useful as a chronotherapy for rheumatoid arthritis due to their prolonged analgesic and anti-inflammatory effects.

  11. Luminescent properties and photostability of thin films of N,N'-phenyl-substituted biphenyls

    Science.gov (United States)

    Chaplanova, Zh. D.; Mikhailovskii, Yu. K.; Agabekov, V. E.; Galinovskii, N. A.; Gracheva, E. A.

    2012-11-01

    We have studied the luminescent properties and morphology of thin films, formed by deposition from solutions (wet) and thermal vacuum deposition (TVD), of 4,4'- bis[(E)-2-[4-(diphenylamino)phenyl]ethenyl]-1,1'-biphenyl (PAB-1) and its 2-oxyhexyl derivative (PAB-2). We have established that the presence of an oxyhexyl side substituent in the structure of N,N'-phenyl-substituted biphenyl promotes quenching of the photoluminescence of the TVD film based on it when stored in air. We show that introducing PAB-2 into a polymer matrix (polymethylmethacrylate, polystyrene, polycyclohexadiene) significantly improves the stability of such composite films when exposed to UV light and to oxygen in the air. We use electron diffraction and atomic force microscopy to establish that these films have an amorphous structure that remains resistant to degradation during photooxidative aging.

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

    Science.gov (United States)

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

    2002-11-01

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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

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

    2005-08-01

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

  15. Impact of Polychlorinated Biphenyls Contamination on Estrogenic Activity in Human Male Serum

    OpenAIRE

    Plíšková, Martina; Vondráček, Jan; Canton, Rocio Fernandez; Nera, Jiřií; Kočan, Anton; Petrík, Ján; Trnovec, Tomáš; Sanderson, Thomas; van den Berg, Martin; Machala, Miroslav

    2005-01-01

    Polychlorinated biphenyls (PCBs) are thought to cause numerous adverse health effects, but their impact on estrogen signaling is still not fully understood. In the present study, we used the ER-CALUX bioassay to determine estrogenic/antiestrogenic activities of the prevalent PCB congeners and PCB mixtures isolated from human male serum. The samples were collected from residents of an area with an extensive environmental contamination from a former PCB production site as well as from a neighbo...

  16. Polychlorinated biphenyl hazards to fish, wildlife, and invertebrates: a synoptic review

    Energy Technology Data Exchange (ETDEWEB)

    Eisler, R.

    1986-04-01

    Entirely as a result of human activities, polychlorinated biphenyls (PCBs) are now distributed worldwide, with measurable concentrations recorded in fishery and wildlife resources from numerous and disparate locations. PCBs elicit a variety of biologic effects including death, birth defects, tumors, and a wasting syndrome. The account summarizes the recent technical literature on the environmental chemistry of PCBs, lists PCB background concentrations in fish, wildlife, and invertebrates; documents their toxic and sublethal properties; and reviews and provides recommendations for the protection of sensitive species.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  18. Congener specific distribution and health risk assessment of polychlorinated biphenyls in urban soils

    OpenAIRE

    Bhupander Kumar; Sanjay Kumar; Chandra Shekhar Sharma

    2012-01-01

    Polychlorinated biphenyls (PCBs) were primarily used in transformers and capacitors, lubricants, flame retardants, plasticizers, paint, carbonless papers, etc. These are capable of long-range atmospheric transport and have been designated as persistent organic pollutants by the Stockholm Convention. Due to their characteristic properties, PCBs are found worldwide in all environmental matrices (including human) and biota. Soils are usually considered to be the source as well as sink for enviro...

  19. Relationships of Thyroid Hormones with Polychlorinated Biphenyls, Dioxins, Furans, and DDE in Adults

    OpenAIRE

    Turyk, Mary E.; Anderson, Henry A.; Persky, Victoria W.

    2007-01-01

    Background Thyroid hormone homeostasis can be disrupted by exposure to ubiquitous and bioaccumulative organochlorines such as polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins (PCDDs). Whereas investigations of health effects have generally focused on human populations with relatively high exposures through occupation, accident, or high fish consumption, general population exposures may also carry risk. Methods We studied associations of total thyroxine (T4) and thyroid-s...

  20. Anaerobic degradation of Polychlorinated Biphenyls (PCBs) and Polychlorinated Biphenyls Ethers (PBDEs), and microbial community dynamics of electronic waste-contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Song, Mengke [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Graduate University of Chinese Academy of Sciences, Beijing 100039 (China); Luo, Chunling, E-mail: clluo@gig.ac.cn [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Li, Fangbai [Guangdong Institute of Eco-environmental and Soil Sciences, Guangzhou 510650 (China); Jiang, Longfei [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); College of Life Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Wang, Yan [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Zhang, Dayi [Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ (United Kingdom); Zhang, Gan [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China)

    2015-01-01

    Environmental contamination caused by electronic waste (e-waste) recycling is attracting increasing attention worldwide because of the threats posed to ecosystems and human safety. In the present study, we investigated the feasibility of in situ bioremediation of e-waste-contaminated soils. We found that, in the presence of lactate as an electron donor, higher halogenated congeners were converted to lower congeners via anaerobic halorespiration using ferrous ions in contaminated soil. The 16S rRNA gene sequences of terminal restriction fragments indicated that the three dominant strains were closely related to known dissimilatory iron-reducing bacteria (DIRB) and those able to perform dehalogenation upon respiration. The functional species performed the activities of ferrous oxidation to ferric ions and further ferrous reduction for dehalogenation. The present study links iron cycling to degradation of halogenated materials in natural e-waste-contaminated soil, and highlights the synergistic roles of soil bacteria and ferrous/ferric ion cycling in the dehalogenation of polychlorinated biphenyls (PCBs) and polybrominated biphenyl ethers (PBDEs). - Highlights: • The biodegradation PCBs and PBDEs in e-waste contaminated soils was studied. • DIRB and arylhalorespiring bacteria were responsive to dehalogenation respiration. • Soil bacteria and Fe ion cycling play synergistic roles in dehalogenation.

  1. Anaerobic degradation of polychlorinated biphenyls (PCBs) and polychlorinated biphenyls ethers (PBDEs), and microbial community dynamics of electronic waste-contaminated soil.

    Science.gov (United States)

    Song, Mengke; Luo, Chunling; Li, Fangbai; Jiang, Longfei; Wang, Yan; Zhang, Dayi; Zhang, Gan

    2015-01-01

    Environmental contamination caused by electronic waste (e-waste) recycling is attracting increasing attention worldwide because of the threats posed to ecosystems and human safety. In the present study, we investigated the feasibility of in situ bioremediation of e-waste-contaminated soils. We found that, in the presence of lactate as an electron donor, higher halogenated congeners were converted to lower congeners via anaerobic halorespiration using ferrous ions in contaminated soil. The 16S rRNA gene sequences of terminal restriction fragments indicated that the three dominant strains were closely related to known dissimilatory iron-reducing bacteria (DIRB) and those able to perform dehalogenation upon respiration. The functional species performed the activities of ferrous oxidation to ferric ions and further ferrous reduction for dehalogenation. The present study links iron cycling to degradation of halogenated materials in natural e-waste-contaminated soil, and highlights the synergistic roles of soil bacteria and ferrous/ferric ion cycling in the dehalogenation of polychlorinated biphenyls (PCBs) and polybrominated biphenyl ethers (PBDEs).

  2. Biphenyl metabolism by rat liver microsomes. Regioselective effects of inducers, inhibitors, and solvents

    Energy Technology Data Exchange (ETDEWEB)

    Haugen, D.A.

    1981-01-01

    The effects of the inducers phenobarbital and 3-methylcholanthrene, the inhibitors 7,8-benzoflavone and 1-benzyl-imidazole, and the solvents methanol, acetone, and dimethyl sulfoxide on the 2-, 3-, and 4-hydroxylation of biphenyl and the O-de-ethylation of 7-ethoxycoumarin by rat liver microsomes were examined. Phenobarbital pretreatment primarily induced 2- and 3-hydroxylation, the latter most dramatically. 3-Methylcholanthrene pretreatment induced 2- and 3-hydroxylation to similar extents. The inhibitors and solvents had regioselective effects on biphenyl metabolism that were characteristic of the uninduced, phenobarbital-induced, and 3-methylcholanthrene-induced microsomes. The presence of multiple forms of cytochrome P-450 in uninduced microsomes is indicated by the regioselective effects of the solvents and the inhibitors. The 3-methylcholanthrene-dependent increases in 2- and 3-hydroxylation appear due to induction of a single form of cytochrome P-450, as indicated by similar dose-response relationships and similar changes in sensitivitty to the inhibitors. The phenobarbital-dependent increases in 2- and 3-hydroxylation appear due to the induction of two forms of cytochrome P-450, as indicated by different changes in sensitivity to the effects of dimethyl sulfoxide and 7,8-benzoflavone. The results indicate that examination of the regioselectivity of biphenyl metabolism is a useful approach for characterizing microsomal mono-oxygenases, and they suggest that the approach may also be useful in the characterization of purified mono-oxygenase systems. (JMT)

  3. Polychlorinated biphenyls in eggs and chlorioallantoic membranes of American alligators (Alligator mississippiensis) from coastal South Carolina

    Energy Technology Data Exchange (ETDEWEB)

    Cobb, G.P.; Wood, P.D. [Clemson Univ., Pendleton, SC (United States); O`Quinn, M. [South Carolina Governor`s School for Science and Mathematics, Hartsville, SC (United States)

    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.

  4. Concentrations of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and polychlorinated biphenyls in blood and breast milk collected from pregnant women in Sapporo City, Japan.

    Science.gov (United States)

    Todaka, Takashi; Hirakawa, Hironori; Kajiwara, Jumboku; Onozuka, Daisuke; Sasaki, Seiko; Miyashita, Chihiro; Yoshioka, Eiji; Yuasa, Motoyuki; Kishi, Reiko; Iida, Takao; Uchi, Hiroshi; Furue, Masutaka

    2011-12-01

    We measured the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (PCBs), and non-dioxin-like PCBs in paired samples of blood and breast milk collected from 67 secundiparas in Sapporo City, Japan, and combined this data with those of the 30 secundiparas previously measured. The arithmetic mean total toxic equivalents (TEQ-WHO) concentrations of PCDDs, PCDFs, non-ortho PCBs, and mono-ortho PCBs in blood and breast milk of the 97 secundiparous subjects were 3.0-23 (mean: 13, median: 14) and 2.7-20 (mean: 8.6, median: 8.5) pg TEQ g(-1) lipid, respectively. The sums of the concentrations of 56 non-dioxin-like PCB congeners that were measured in the subjects' blood and breast milk were 16-326 (mean: 107, median: 100) and 12-252 (mean: 73, median: 67) ng g(-1) lipid, respectively. The partitioning ratios of individual congeners of PCDDs, PCDFs, dioxin-like PCBs, and non-dioxin-like PCBs from blood to breast milk in secundiparas were almost the same as those of primiparas that have been recently reported, suggesting that the partitioning ratios of these compounds from maternal blood to breast milk in women is little affected by delivery. Furthermore, the partition of PCB congeners with chlorine at the 2-, 3-, 4'-, and 5-positions or the 2-, 4-, 4'-, and 5-positions of the biphenyl ring from the blood to the breast milk tended to occur at a higher level than that of other congeners. In particular, the levels of tetraCB-74 and hexaCB-146 in the breast milk for both primiparous and secundiparous mothers were slightly higher than those in the blood.

  5. A high-throughput screen against pantothenate synthetase (PanC identifies 3-biphenyl-4-cyanopyrrole-2-carboxylic acids as a new class of inhibitor with activity against Mycobacterium tuberculosis.

    Directory of Open Access Journals (Sweden)

    Anuradha Kumar

    Full Text Available The enzyme pantothenate synthetase, PanC, is an attractive drug target in Mycobacterium tuberculosis. It is essential for the in vitro growth of M. tuberculosis and for survival of the bacteria in the mouse model of infection. PanC is absent from mammals. We developed an enzyme-based assay to identify inhibitors of PanC, optimized it for high-throughput screening, and tested a large and diverse library of compounds for activity. Two compounds belonging to the same chemical class of 3-biphenyl-4- cyanopyrrole-2-carboxylic acids had activity against the purified recombinant protein, and also inhibited growth of live M. tuberculosis in manner consistent with PanC inhibition. Thus we have identified a new class of PanC inhibitors with whole cell activity that can be further developed.

  6. Session 4: Enhanced sulfur resistance and catalytic properties of Pd-Pt supported on TiO{sub 2} - modified Al{sub 2}O{sub 3} in the hydrogenation of biphenyl and HDS of dibenzothiophene

    Energy Technology Data Exchange (ETDEWEB)

    Nunez, S.; Montesinos, A.; Viveros, T.; Los Reyes, J.A. de [Universidad Autonoma Metropolitana-Iztapalapa (Mexico)

    2004-07-01

    In the hydrotreatment (HDT) of petroleum cuts to produce diesel, the selection of active and highly selective catalysts for hydrogenation (HYD) of aromatics is a fundamental issue in the second stage of multi-staged processes. It is well know that precious metals (Pd-Pt mainly) are suitable for this reaction. However, sulfur compounds at low concentration may poison these catalysts. Thus, this work focuses on the evaluation in the hydrogenation of an aromatic compound of Pd-Pt catalysts supported on TiO{sub 2}-modified Al{sub 2}O{sub 3} by using two reactions in presence of sulfur, the hydrogenation (HYD) of biphenyl (BP) and the hydrodesulfurization (HDS) of dibenzothiophene (DBT). The obtained experimental results are given and explained. (O.M.)

  7. Historical intake and elimination of polychlorinated biphenyls and organochlorine pesticides by the Australian population reconstructed from biomonitoring data.

    Science.gov (United States)

    Bu, Qingwei; MacLeod, Matthew; Wong, Fiona; Toms, Leisa-Maree L; Mueller, Jochen F; Yu, Gang

    2015-01-01

    Quantifying the competing rates of intake and elimination of persistent organic pollutants (POPs) in the human body is necessary to understand the levels and trends of POPs at a population level. In this paper we reconstruct the historical intake and elimination of ten polychlorinated biphenyls (PCBs) and five organochlorine pesticides (OCPs) from Australian biomonitoring data by fitting a population-level pharmacokinetic (PK) model. Our analysis exploits two sets of cross-sectional biomonitoring data for PCBs and OCPs in pooled blood serum samples from the Australian population that were collected in 2003 and 2009. The modeled adult reference intakes in 1975 for PCB congeners ranged from 0.89 to 24.5ng/kgbw/day, lower than the daily intakes of OCPs ranging from 73 to 970ng/kgbw/day. Modeled intake rates are declining with half-times from 1.1 to 1.3years for PCB congeners and 0.83 to 0.97years for OCPs. The shortest modeled intrinsic human elimination half-life among the compounds studied here is 6.4years for hexachlorobenzene, and the longest is 30years for PCB-74. Our results indicate that it is feasible to reconstruct intakes and to estimate intrinsic human elimination half-lives using the population-level PK model and biomonitoring data only. Our modeled intrinsic human elimination half-lives are in good agreement with values from a similar study carried out for the population of the United Kingdom, and are generally longer than reported values from other industrialized countries in the Northern Hemisphere.

  8. Prenatal exposure to polychlorinated biphenyls and their hydroxylated metabolites is associated with neurological functioning in 3-month-old infants.

    Science.gov (United States)

    Berghuis, Sietske A; Soechitram, Shalini D; Sauer, Pieter J J; Bos, Arend F

    2014-12-01

    Polychlorinated biphenyls (PCBs) are environmental chemicals which are potentially toxic to the developing brain. Their hydroxylated metabolites (OH-PCBs) are suggested to be even more toxic. Knowledge about the health effects of prenatal OH-PCB exposure is limited. We aimed to determine whether prenatal background exposure to PCBs and OH-PCBs is associated with neurological functioning in 3-month-old boys and girls. In a Dutch observational cohort study, we measured 10 PCBs and 6 OH-PCBs in maternal blood samples of 98 pregnant women. We assessed their infants neurologically with Touwen examination at 3 months and calculated an Optimality Score (OS, range 0-53, low-high optimality). We calculated correlation coefficients between compound levels and OS. Subsequently, we tested whether levels were associated with specific clusters and whether levels differed between infants with "normal" (dysfunction on ≤1 cluster) and "non-optimal" development (dysfunction on ≥2 clusters). The mean OS was 48 (range 44-52). Higher exposure to PCB-146 correlated significantly with higher OS (r = 0.209; p = 0.039). In boys, higher exposure to 4-OH-PCB-107 correlated with lower OS (r = -0.305; p = 0.030). Higher exposure to 9 PCBs and the sum of all PCBs was associated with better visuomotor and/or better sensorimotor function. Infants classified as "non-optimal" (n = 36) had significantly lower prenatal exposure to 6 PCBs and the sum of all PCBs (p < 0.05) compared with infants classified as "normal" (n = 62). In conclusion, higher prenatal exposure to Dutch background PCB levels is associated with better neurological functioning in 3-month-old infants. Prenatal exposure to 4-OH-PCB-107 is associated with less optimal neurological functioning in boys.

  9. Levels and congener profiles of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and dioxin-like polychlorinated biphenyls in cow's milk collected in Campania, Italy.

    Science.gov (United States)

    Esposito, M; Cavallo, S; Serpe, F P; D'Ambrosio, R; Gallo, P; Colarusso, G; Pellicanò, R; Baldi, L; Guarino, A; Serpe, L

    2009-11-01

    Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and certain dioxin-like polychlorinated biphenyls (dl-PCBs) are a family of chemically-related lipophilic compounds characterized by similar toxicity. Due to their properties they are universally distributed in the environment and classified as persistent organic pollutants (POPs). From most of studies carried out to evaluate human dietary intake, milk and dairy products result as a major contributors of PCDD/Fs uptake. Of course the main source of milk contamination is animal feeds. Lactating ruminants, cows included, transfer these compounds to the food chain by ingestion of contaminated vegetables or soil. Their resistance to degradation and a high lipophilicity means that PCDD/Fs and dl-PCBs may be accumulated into fat tissues from which they are transferred to milk during lactation period. Seventy-nine cows milk samples, collected in the monitoring plan 2008, were analyzed for PCDD/Fs and dl-PCBs. Eleven milk samples were non-compliant corresponding to five breeding livestock located in Caserta province. The distribution of PCDD/Fs and dl-PCBs congeners in these samples was examined in order to determine the likely sources of dioxins. The results show that the congener profile is characterized by a prevalence of PCDFs in respect of PCDDs, that represents the typical pattern of thermal origin contamination.

  10. Lanthanide-Potassium Biphenyl-3,3'-disulfonyl-4,4'-dicarboxylate Frameworks: Gas Sorption, Proton Conductivity, and Luminescent Sensing of Metal Ions.

    Science.gov (United States)

    Zhou, Li-Juan; Deng, Wei-Hua; Wang, Yu-Ling; Xu, Gang; Yin, Shun-Gao; Liu, Qing-Yan

    2016-06-20

    A novel sulfonate-carboxylate ligand of biphenyl-3,3'-disulfonyl-4,4'-dicarboxylic acid (H4-BPDSDC) and its lanthanide-organic frameworks {[LnK(BPDSDC)(DMF)(H2O)]·x(solvent)}n (JXNU-2, where JXNU denotes Jiangxi Normal University, DMF indicates dimethylformamide, and Ln = Sm(3+), Eu(3+), and Pr(3+)) were synthesized and structurally characterized. The three isomorphous lanthanide compounds feature three-dimensional frameworks constructed from one-dimensional (1D) rod-shaped heterometallic Ln-K secondary building units and are an illustration of a Kagome-like lattice with large 1D hexagonal channels and small 1D trigonal channels. The porous material of the representive JXNU-2(Sm) has an affinity to quadrupolar molecules such as CO2 and C2H2. In addition, the JXNU-2(Sm) compound exhibits humidity- and temperature-dependent proton conductivity with a large value of 1.11 × 10(-3) S cm(-1) at 80 °C and 98% relative humidity. The hydrophilic sulfonate group on the surface of channels facilitates enrichment of the solvate water molecules in the channels, which enhances the proton conductivity of this material. Moreover, the JXNU-2(Eu) material with the characteristic bright red color shows the potential for recognition of K(+) and Fe(3+) ions. The enhancing Eu(3+) luminescence with the K(+) ion and quenching Eu(3+) luminescence with the Fe(3+) ion can be associated with the functional groups of the organic ligand.

  11. Polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in sediments of Liaohe River: levels, spatial and temporal distribution, possible sources, and inventory.

    Science.gov (United States)

    Lv, Jiapei; Zhang, Yuan; Zhao, Xin; Zhou, Changbo; Guo, Changsheng; Luo, Yi; Meng, Wei; Zou, Guofang; Xu, Jian

    2015-03-01

    Spatial and seasonal variations of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in the sediment of Liaohe River were investigated in this study. A total of 29 surface sediment samples were collected in May and September in 2013. Results showed that levels of the two classes of compounds were higher in September than in May. The total concentration of PBDEs (∑8PBDEs) ranged from 0.30 to 5.09 ng g(-1) in May and from 0.17 to 13.73 ng g(-1) in September, respectively, and BDE 209 was the dominant compound. The total concentration of PCBs (∑33PCBs) was in the range of 4.92-76.86 and 11.69-179.61 ng g(-1) in May and September, respectively, with tri- and tetra-CBs dominated in the total PCBs in the sediments. According to the congener profiles and the principal component analysis, the major sources of PCBs and PBDEs in sediments of Liaohe River were from the usage of commercial products and industrial activities, and the degradation of high brominated BDEs also contributed to the current PBDEs in the sediments. The mass inventories of PBDEs and PCBs in the sediments of Liaohe River were 1.74 and 21.96 t, respectively, indicating that Liaohe River sediments may act as the potential sources of PBDEs and PCBs to the downstream coastal areas.

  12. K Basin sludge polychlorinated biphenyl removal technology assessment

    Energy Technology Data Exchange (ETDEWEB)

    Ashworth, S.C.

    1998-08-25

    The two Hanford K Basins are water-filled concrete pools that contain over 2,100 metric tons of N Reactor fuel elements stored in aluminum or stainless steel canisters. During the time the fuel has been stored, approximately 50 m3 of heterogeneous solid material have accumulated in the basins. This material, referred to as sludge, is a mixture of fuel corrosion products, metallic bits of spent fuel and zirconium clad iron and metal corrosion products and silica from migrating sands. Some of the sludges also contain PCBs. The congener group of PCBs was identified as Aroclor 1254. The maximum concentration of sludge PCBS was found to be 140 ppm (as settled wet basis). However, the distribution of the PCBs is non-uniform throughout the sludge (i.e., there are regions of high and low concentrations and places where no PCBs are present). Higher concentrations could be present at various locations. Aroclors 1016/1242, 1221, 1248, 1254, and 1260 were identified and quantified in K West (KW) Canister sludge. In some of these samples, the concentration of 1260 was higher than 1254. The sludge requires pre-treatment to meet tank farm waste acceptance criteria, Among the numerous requirements, the sludge should be retreated so that it does not contain regulated levels of Toxic Substances Control Act (TSCA) compounds. Because of their stable chemistry and relative insolubility in water, PCBs are difficult to treat. They also resist degradation from heat and electrical charges. This stability has resulted in environmental persistence which has prompted the development of a variety of new cleanup processes including supercritical processes, advanced oxidation, dehalogenation and others. Hopefully, most of the new processes are discussed herein. Information on new processes are being received and will be evaluated in a future revision.

  13. Optimizing Polychlorinated Biphenyl Degradation by Flavonoid-Induced Cells of the Rhizobacterium Rhodococcus erythropolis U23A.

    Directory of Open Access Journals (Sweden)

    Thi Thanh My Pham

    Full Text Available 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

  14. Estrogenic compounds -endocrine disruptors

    Directory of Open Access Journals (Sweden)

    Munteanu Constantin

    2011-11-01

    Full Text Available Endocrine disruptors (polychlorinated biphenyls, dichlorodiphenyl-trichloroethane [DDT], dioxin, and some pesticides are estrogen-like and anti-androgenic chemicals in the environment. They mimic natural hormones, inhibit the action of hormones, or alter the normal regulatory function of the endocrine system and have potential hazardous effects on male reproductive axis causing infertility. Although testicular and prostate cancers, abnormal sexual development, undescended testis, chronic inflammation, Sertoli-cell-only pattern, hypospadias, altered pituitary and thyroid gland functions are also observed, the available data are insufficient to deduce worldwide conclusions.

  15. Biotransformation of various substituted aromatic compounds to chiral dihydrodihydroxy derivatives.

    Science.gov (United States)

    Raschke, H; Meier, M; Burken, J G; Hany, R; Müller, M D; Van Der Meer, J R; Kohler, H P

    2001-08-01

    The biotransformation of four different classes of aromatic compounds by the Escherichia coli strain DH5alpha(pTCB 144), which contained the chlorobenzene dioxygenase (CDO) from Pseudomonas sp. strain P51, was examined. CDO oxidized biphenyl as well as monochlorobiphenyls to the corresponding cis-2,3-dihydro-2,3-dihydroxy derivatives, whereby oxidation occurred on the unsubstituted ring. No higher substituted biphenyls were oxidized. The absolute configurations of several monosubstituted cis-benzene dihydrodiols formed by CDO were determined. All had an S configuration at the carbon atom in meta position to the substituent on the benzene nucleus. With one exception, the enantiomeric excess of several 1,4-disubstituted cis-benzene dihydrodiols formed by CDO was higher than that of the products formed by two toluene dioxygenases. Naphthalene was oxidized to enantiomerically pure (+)-cis-(1R,2S)-dihydroxy-1,2-dihydronaphthalene. All absolute configurations were identical to those of the products formed by toluene dioxygenases of Pseudomonas putida UV4 and P. putida F39/D. The formation rate of (+)-cis-(1R,2S)-dihydroxy-1,2-dihydronaphthalene was significantly higher (about 45 to 200%) than those of several monosubstituted cis-benzene dihydrodiols and more than four times higher than the formation rate of cis-benzene dihydrodiol. A new gas chromatographic method was developed to determine the enantiomeric excess of the oxidation products.

  16. Synthesis, structural and electrochemical characterization of benzimidazole compounds exhibiting a smectic C liquid crystal phase

    Science.gov (United States)

    Wei, Bingzhuo; Tan, Shuai; Liang, Ting; Cao, Siyu; Wu, Yong

    2017-04-01

    Mesomorphic benzimidazole compounds were prepared from a biphenyl benzoate based precursor by substitution reaction of alkyl bromide with 2-mercaptobenzimidazole. Molecular structures of the benzimidazole compounds were characterized by nuclear magnetic resonance (NMR), Fourier transform infrared (FT-IR) spectroscopy and elemental analysis. Differential scanning calorimetry (DSC) measurements and polarizing optical microscopic (POM) observations revealed that the benzimidazole compounds exhibited a thermotropic smectic C (SC) phase. Temperature dependent X-ray diffraction (XRD) patterns suggested a tilted bilayer smectic structure in which intermolecular hydrogen bonds between benzimidazole moieties formed lamellar arrangement. Electrochemical impedance spectroscopy (EIS) characterization suggested that the SC phase favored anhydrous proton conduction of the benzimidazole compounds and the proton conductivities showed an Arrhenius temperature dependence.

  17. Biogenic volatile organic compounds - small is beautiful

    Science.gov (United States)

    Owen, S. M.; Asensio, D.; Li, Q.; Penuelas, J.

    2012-12-01

    While canopy and regional scale flux measurements of biogenic volatile organic compounds (bVOCs) are essential to obtain an integrated picture of total compound reaching the atmosphere, many fascinating and important emission details are waiting to be discovered at smaller scales, in different ecological and functional compartments. We concentrate on bVOCs below ground to allelopathy. A gradient of monoterpene concentration was found in soil around Pinus sylvestris and Pinus halepensis, decreasing with distance from the tree. Some compounds (α-pinene, sabinene, humulene and caryophyllene) in mineral soil were linearly correlated with the total amount of each compound in the overlying litter, indicating that litter might be the dominant source of these compounds. However, α-pinene did not fall within the correlation, indicating a source other than litter, probably root exudates. We also show that rhizosphere bVOCs can be a carbon source for soil microbes. In a horizontal gradient from Populus tremula trees, microbes closest to the tree trunk were better enzymatically equipped to metabolise labeled monoterpene substrate. Monoterpenes can also increase the degradation rate in soil of the persistant organic pollutants, likely acting as analogues for the cometabo-lism of polychlorinated biphenyls (PCBs) Flowers of a ginger species (Alpinia kwangsiensis) and a fig species (Ficus hispida) showed different bVOC signals pre- and post pollination. For Ficus hispida, there are three floral stages of a fig-wasp dependency mechanism: receptive, post pollinator and interfloral. Of 28 compounds detected, transcaryophyllene with trans-β-farnesene were the most important at the receptor stage, trans-caryophyllene was the most abundant at the post-pollinator stage, and isoprene was the most abundant in the interfloral stage. Alpinia kwangsiensis presents two morphologies for the reproductive parts of the flower. The "anaflexistyle" morphology has the flower style lowered in the

  18. Use of feathers to assess polychlorinated biphenyl and organochlorine pesticide exposure in top predatory bird species of Pakistan.

    Science.gov (United States)

    Abbasi, Naeem Akhtar; Eulaers, Igor; Jaspers, Veerle L B; Chaudhry, Muhammad Jamshed Iqbal; Frantz, Adrien; Ambus, Per Lennart; Covaci, Adrian; Malik, Riffat Naseem

    2016-11-01

    Little is known about the levels of organochlorines (OCs) in predatory bird species from Asia or the factors governing their concentrations. This study is the first report on concentrations of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in predatory birds of Pakistan. The concentrations of PCBs and OCPs were investigated using tail feathers of ten different species of predatory birds. In addition, concentration differences among body, tail, primary and secondary feathers were investigated for six individuals of black kite (Milvus migrans). Ranges of concentrations were highest for dichlorodiphenyldichloroethylene (p,p'-DDE: 0.11-2163ngg(-1) dry wt.) followed by dichlorodiphenyltrichloroethane (p,p'-DDT: 0.36-345ngg(-1) dry wt.), hexachlorobenzene (HCB: 0.02-34ngg(-1) dry wt.), ∑PCBs (0.03-16ngg(-1) dry wt.) and trans-nonachlor (TN; 0.01-0.13ngg(-1) dry wt.). CB 118, 153, 138, and 180 along with p,p'-DDE were found as the most prevalent compounds. ∑PCBs and ∑DDTs were significantly different among species (both p<0.01) and omnivorous, scavengers, carnivorous and piscivorous trophic guilds (all p<0.03). Only ∑PCBs were significantly differentamong different families of birds (p<0.01). Values of stable isotopes (δ(13)C and δ(15)N) differed significantly (all p<0.01) among species, families, trophic guilds as well as terrestrial and aquatic habitat but not between nocturnal and diurnal predators (p=0.22 for δ(13)C; p=0.50 for δ(15)N). Concentrations of ∑PCBs, ∑DDTs and trans-nonachlor, but not HCB (p=0.86), were significantly different among different feather types (all p<0.01). Trophic and taxonomic affiliation as well as dietary carbon sources (δ(13)C) for species were identified as the variables best explaining the observed variation in exposure to the studied compounds. The significance of contributing factors responsible for OC contamination differences in predatory birds should be further elucidated in future studies.

  19. Suppression of Peroxisomal Enzyme Activities and Cytochrome P450 4A Isozyme Expression by Congeneric Polybrominated and Polychlorinated Biphenyls

    Directory of Open Access Journals (Sweden)

    Larry W. Robertson

    2007-09-01

    Full Text Available The purpose of this study was to determine the effects of PCBs and PBBs on peroxisome proliferator-activated receptor-α-(PPARα- associated enzyme activities or protein levels. Male Sprague-Dawley rats were administered a single IP injection (150 μmol/kg of either 3,3′,4,4′-tetrabromobiphenyl, 3,3′,4,4′-tetrachlorobiphenyl, 3,3′,5,5′-tetrabromobiphenyl, 2′,3,3′,4,5-pentachlorobiphenyl, 3,3′,4,4′,5-pentachlorobiphenyl, 2,2′,3,3′,5,5′-hexachlorobiphenyl, or 3,3′,4,4′,5,5′-hexabromobiphenyl in corn oil (10 ml/kg. One week later, the activities of catalase, peroxisomal fatty acyl-CoA oxidase, and peroxisomal beta-oxidation as well as cytochrome P450 4A (CYP4A protein content were determined in subcellular liver fractions. None of the peroxisomal enzyme activities were significantly increased by any of the halogenated biphenyl congeners tested. Except for minor (approx. 25% increases in the total CYP4A content following treatment with 2,2′,3,3′,5,5′-hexachlorobiphenyl and 3,3′,5,5′-tetrabromobiphenyl, CYP4A protein contents were not increased by any treatment. The two Ah receptor agonists, 3,3′,4,4′-tetrabromobiphenyl and 3,3′,4,4′,5-pentachlorobiphenyl, significantly diminished the liver content of CYP4A proteins and activities of the peroxisomal enzymes studied. Since a range of congeners with different biologic and toxicologic activities were selected for this study, it may be concluded that the polyhalogenated biphenyls do not induce peroxisome proliferation in the male rat, but rather certain members of this class of compounds down regulate peroxisome-associated enzymes. Since PCBs and PBBs do not increase

  20. Identification of bacteria utilizing biphenyl, benzoate, and naphthalene in long-term contaminated soil.

    Directory of Open Access Journals (Sweden)

    Ondrej Uhlik

    Full Text Available Bacteria were identified associated with biodegradation of aromatic pollutants biphenyl, benzoate, and naphthalene in a long-term polychlorinated biphenyl- and polyaromatic hydrocarbon-contaminated soil. In order to avoid biases of culture-based approaches, stable isotope probing was applied in combination with sequence analysis of 16 S rRNA gene pyrotags amplified from (13C-enriched DNA fractions. Special attention was paid to pyrosequencing data analysis in order to eliminate the errors caused by either generation of amplicons (random errors caused by DNA polymerase, formation of chimeric sequences or sequencing itself. Therefore, sample DNA was amplified, sequenced, and analyzed along with the DNA of a mock community constructed out of 8 bacterial strains. This warranted that appropriate tools and parameters were chosen for sequence data processing. (13C-labeled metagenomes isolated after the incubation of soil samples with all three studied aromatics were largely dominated by Proteobacteria, namely sequences clustering with the genera Rhodanobacter Burkholderia, Pandoraea, Dyella as well as some Rudaea- and Skermanella-related ones. Pseudomonads were mostly labeled by (13C from naphthalene and benzoate. The results of this study show that many biphenyl/benzoate-assimilating bacteria derive carbon also from naphthalene, pointing out broader biodegradation abilities of some soil microbiota. The results also demonstrate that, in addition to traditionally isolated genera of degradative bacteria, yet-to-be cultured bacteria are important players in bioremediation. Overall, the study contributes to our understanding of biodegradation processes in contaminated soil. At the same time our results show the importance of sequencing and analyzing a mock community in order to more correctly process and analyze sequence data.

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

    Science.gov (United States)

    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.

  2. Weakly faceted cellular patterns versus growth-induced plastic deformation in thin-sample directional solidification of monoclinic biphenyl.

    Science.gov (United States)

    Börzsönyi, Tamás; Akamatsu, Silvère; Faivre, Gabriel

    2009-11-01

    We present an experimental study of thin-sample directional solidification (T-DS) in impure biphenyl. The platelike growth shape of the monoclinic biphenyl crystals includes two low-mobility (001) facets and four high-mobility {110} facets. Upon T-DS, biphenyl plates oriented with (001) facets parallel to the sample plane can exhibit either a strong growth-induced plastic deformation (GID), or deformation-free weakly faceted (WF) growth patterns. We determine the respective conditions of appearance of these phenomena. GID is shown to be a long-range thermal-stress effect, which disappears when the growth front has a cellular structure. An early triggering of the cellular instability allowed us to avoid GID and study the dynamics of WF patterns as a function of the orientation of the crystal.

  3. Polychlorinated biphenyl (PCB) induction of CYP3A4 enzyme activity in healthy Faroese adults

    DEFF Research Database (Denmark)

    Petersen, Maria Skaalum; Halling, Jónrit; Damkier, Per

    2007-01-01

    The CYP3A4 enzyme is, along with other cytochrome P450 enzymes, involved in the metabolism of environmental pollutants and is highly inducible by these substances. A commercial polychlorinated biphenyl (PCB) mixture, 1,1,1,-trichloro-2-(o-chlorophenyl), 2-(p'-chlorophenyl)ethane (o,p'-DDT) and 1...... analysis showed significant associations between 6beta-OHC/FC ratios and summation PCB, PCB-TEQ and p,p'-DDE, o,p'-DDT and HCB, respectively, but the associations were statistically significant for men only....

  4. Electrochemical and optical properties of biphenyl bridged-dicarbazole oligomer films: Electropolymerization and electrochromism

    Energy Technology Data Exchange (ETDEWEB)

    Koyuncu, Sermet [Department of Chemistry, Faculty of Sciences and Arts, Canakkale Onsekiz Mart University, 17020 Canakkale (Turkey); Can Vocational School, Canakkale Onsekiz Mart University, 17400 Canakkale (Turkey)], E-mail: sermetkoyuncu@hotmail.com; Gultekin, Burak [Solar Energy Institute, Ege University, 35100 Bornova, Izmir (Turkey); Zafer, Ceylan [Solar Energy Institute, Ege University, 35100 Bornova, Izmir (Turkey)], E-mail: ceylan.zafer@ege.edu.tr; Bilgili, Hakan; Can, Mustafa; Demic, Serafettin [Solar Energy Institute, Ege University, 35100 Bornova, Izmir (Turkey); Kaya, Ismet [Department of Chemistry, Faculty of Sciences and Arts, Canakkale Onsekiz Mart University, 17020 Canakkale (Turkey); Icli, Siddik [Solar Energy Institute, Ege University, 35100 Bornova, Izmir (Turkey)

    2009-10-01

    4,4'-Di(N-carbazoyl)biphenyl monomer (CBP) was synthesized and coated onto ITO-glass surface by electrochemical oxidative polymerization. Its CV shows two distinct one-electron and stepwise oxidation processes occurred at 1.29 and 1.61 V. By using this property, the monomer was electrochemically polymerized separately at these oxidation states and thus, two different oligomer films were obtained afterwards. Their spectro-electrochemical and electrochromic properties were also investigated. Switching ability of the oligomers was evaluated by kinetic studies upon measuring the percent transmittance (%T) at their maximum contrast point, indicating that these oligomers were found to be suitable material for electrochromic devices.

  5. Whole-Cell Fluorescent Biosensors for Bioavailability and Biodegradation of Polychlorinated Biphenyls

    Directory of Open Access Journals (Sweden)

    David Ryan

    2010-02-01

    Full Text Available Whole-cell microbial biosensors are one of the newest molecular tools used in environmental monitoring. Such biosensors are constructed through fusing a reporter gene such as lux, gfp or lacZ,to a responsive promoter. There have been many reports of the applications of biosensors, particularly their use in assaying pollutant toxicity and bioavailability. This paper reviews the basic concepts behind the construction of whole-cell microbial biosensors for pollutant monitoring, and describes the applications of two such biosensors for detecting the bioavailability and biodegradation of Polychlorinated Biphenyls (PCBs.

  6. Library of biphenyl privileged substructures using a safety-catch linker approach

    DEFF Research Database (Denmark)

    Severinsen, Rune; Bourne, Gregory T; Tran, Tran T

    2008-01-01

    A biphenyl privileged structure library containing three attachment points were synthesized using a catechol-based safety-catch linker strategy. The method requires the attachment of a bromo-acid to the linker, followed by a Pd-catalyzed Suzuki cross-coupling reaction. Further derivatization......, activation of the linker with strong acid and aminolysis afforded the respective products in high purity and good overall yield. To show the versatility of the synthesis, a 199-member library was generated. The library samples both conformational and chemical diversity about a well-known privileged...

  7. Development and characterization of new polyclonal antibodies specific for three polychlorinated biphenyls

    Institute of Scientific and Technical Information of China (English)

    Han Yu Chen; Hui Sheng Zhuang; Chun Zhou

    2009-01-01

    Three polychlorinated biphenyls(PCBs)congeners and their corresponding haptens bearing four carbon length carboxylic groups that can be linked to a protein for raising antibodies were synthesized.The three resultant immunogens were fabricated and used to stimulate immune responses in rabbits to survey the characteristics of the haptens.Three of the resultant polyclonal antibodies(Pabs)were obtained.The antiserum exhibited relatively high antibody titres(1:32-64)in double agar diffusion.◎2008 Hui Sheng Zhuang.Published by Elsevier B.V.on behalf of Chinese Chemical Society.All rights reserved.

  8. Biodegradation of biphenyl and removal of 2-chlorobiphenyl by Pseudomonas sp. KM-04 isolated from PCBs-contaminated mine impacted soil

    Science.gov (United States)

    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

  9. Mechanistic insights into the specificity of human cytosolic sulfotransferase 2A1 (hSULT2A1) for hydroxylated polychlorinated biphenyls through the use of fluoro-tagged probes.

    Science.gov (United States)

    Ekuase, E J; van 't Erve, T J; Rahaman, A; Robertson, L W; Duffel, M W; Luthe, G

    2016-02-01

    Determining the relationships between the structures of substrates and inhibitors and their interactions with drug-metabolizing enzymes is of prime importance in predicting the toxic potential of new and legacy xenobiotics. Traditionally, quantitative structure activity relationship (QSAR) studies are performed with many distinct compounds. Based on the chemical properties of the tested compounds, complex relationships can be established so that models can be developed to predict toxicity of novel compounds. In this study, the use of fluorinated analogues as supplemental QSAR compounds was investigated. Substituting fluorine induces changes in electronic and steric properties of the substrate without substantially changing the chemical backbone of the substrate. In vitro assays were performed using purified human cytosolic sulfotransferase hSULT2A1 as a model enzyme. A mono-hydroxylated polychlorinated biphenyl (4-OH PCB 14) and its four possible mono-fluoro analogues were used as test compounds. Remarkable similarities were found between this approach and previously published QSAR studies for hSULT2A1. Both studies implicate the importance of dipole moment and dihedral angle as being important to PCB structure in respect to being substrates for hSULT2A1. We conclude that mono-fluorinated analogues of a target substrate can be a useful tool to study the structure activity relationships for enzyme specificity.

  10. Global pollution monitoring of polychlorinated dibenzo-p-dioxins (PCDDs), furans (PCDFs) and coplanar polychlorinated biphenyls (coplanar PCBs) using skipjack tuna as bioindicator

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, D.; Watanabe, M.; Subraminian, A.N.; Tanabe, S. [Ehime Univ. (Japan); Tanaka, H. [National Research Inst. of Fisheries and Environment of Inland Sea (Japan); Fillmann, G. [Fundacao Univ. Federal do Rio Grande (Brazil); Lam, P.K.S.; Zheng, G.J. [City Univ. of Hong Kong (Hong Kong); Muchtar, M.; Razak, H. [Indonesian Inst. of Sciences (Indonesia); Prudente, M. [De La Salle Univ. (Philippines); Chung, K. [Sungkyunkwan Univ. (Korea)

    2004-09-15

    Worldwide contamination by dioxins and related compounds, such as polychlorinated dibenzop- dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and coplanar polychlorinated biphenyls (coplanar PCBs) representing persistent organic pollutants (POPs) have been of great concern due to their persistency in the environment, highly bioaccumulative nature and adverse effects on wildlife and humans. Several studies on air samples and marine organisms from open seas suggested a long range transport of these compounds through atomosphere. Although several investigators have monitored dioxins pollution in localized areas, information on the global distribution of dioxins which can explain their atomospheric transport, behavior and fate are still limited. Skipjack tuna is primarily distributed from offshore waters to open seas in tropical and temperate regions almost all over the world such as the Pacific, Atlantic and Indian Oceans6. This species is an important commercial fish and its ecology and biology has been well studied. Moreover, suitability of skipjack tuna for global monitoring of organic pollutants (DDTs, HCHs PBDEs, organotins, etc.) has been established in our previous report, indicating that migration pattern, growth stage and sex of these animals have no or little effect on the variations of POPs residue levels in their bodies. Hence this species reflected POPs pollution levels in seawater when and where they were collected, caused by the rapid equilibrium partitioning between seawater and body lipid. These facts made skipjack tuna a suitable bioindicator for monitoring the contamination status of dioxins and related compounds. The objectives of this study are to elucidate the global distribution of dioxins (PCDD/Fs and coplanar PCBs) in offshore waters and open seas, and to understand the transport and behaviour of these chemicals using skipjack tuna as bioindicator.

  11. Ab initio study of long-range electron transfer between biphenyl anion radical and naphthalene

    Institute of Scientific and Technical Information of China (English)

    李象远; 肖顺清; 何福城

    1999-01-01

    After the separation of the donor, the aeceptor, and the σ-type bridge from the π-σ-π system, the geometries of biphenyl, biphenyl anion radical, naphthalene, and naphthalene anion radical are optimized, and then the reorganization energy for the intermolecular electron transfer (ET) at the levels of HF/4-31G and HF/DZP is calculated. The ET matrix elements of the self-exchange reactions of the π-σ-π systems have been calculated by means of both the direct calculation based on the variational principle, and the transition energy between the molecular orbitals at the linear coordinate R=0.5. For the cross reactions, the ET matrix element and the geometry of the transition state are determined by searching the minimum energy splitting △min along the reaction coordinate. In the evaluation of the solvent reorganization energy of the ET in solution, the Marcus’ two-sphere model has been invoked. A few of ET rate constants for the intramolecular ET reactions for the π-σ-π systems, which contain

  12. Transcriptional Response of Rhodococcus aetherivorans I24 to Polychlorinated Biphenyl-Contaminated Sediments

    KAUST Repository

    Puglisi, Edoardo

    2010-04-06

    We used a microarray targeting 3,524 genes to assess the transcriptional response of the actinomycete Rhodococcus aetherivorans I24 in minimal medium supplemented with various substrates (e. g., PCBs) and in both PCB-contaminated and non-contaminated sediment slurries. Relative to the reference condition (minimal medium supplemented with glucose), 408 genes were upregulated in the various treatments. In medium and in sediment, PCBs elicited the upregulation of a common set of 100 genes, including gene-encoding chaperones (groEL), a superoxide dismutase (sodA), alkyl hydroperoxide reductase protein C (ahpC), and a catalase/peroxidase (katG). Analysis of the R. aetherivorans I24 genome sequence identified orthologs of many of the genes in the canonical biphenyl pathway, but very few of these genes were upregulated in response to PCBs or biphenyl. This study is one of the first to use microarrays to assess the transcriptional response of a soil bacterium to a pollutant under conditions that more closely resemble the natural environment. Our results indicate that the transcriptional response of R. aetherivorans I24 to PCBs, in both medium and sediment, is primarily directed towards reducing oxidative stress, rather than catabolism. © 2010 Springer Science+Business Media, LLC.

  13. Tissue damage after acute intoxication by polychlorinated biphenyls (PCBs in cockroaches Blattella germanica

    Directory of Open Access Journals (Sweden)

    S Lambiase

    2009-06-01

    Full Text Available It is common knowledge that polychlorinated biphenyls (PCBs represent a serious threat to the health of both vertebrates and invertebrates. As far as the former are concerned, especially as regards human beings, a broad literature describes the direct and indirect effects induced by the PCBs on their systems and organs. Among invertebrates, the information available is mostly related to arthropods and is, however, very scarce. The aim of this work was to evaluate the effects of polychlorinated biphenyls (PCBs on tissues and organs of individuals belonging to a species of Blattaria (Blattella germanica treated with various doses of this toxic material. The pathologies found became more serious as the dosage increased and were present throughout the entire digestive system, in the fat body and in the male gonads: in these areas cell and tissue breakdown and severely damaged spermiogenesis were observed. In particular, the testicles, Malpighian tubules and fat body accumulated an amorphous basophilic PAS-positive substance. Furthermore, the NOS-dependent NADPH diaphorase activity pattern in the retina and optic lobes was more evident in the treated than in the control insects.

  14. Enhanced Polychlorinated Biphenyl Removal in a Switchgrass Rhizosphere by Bioaugmentation with Burkholderia xenovorans LB400.

    Science.gov (United States)

    Liang, Yi; Meggo, Richard; Hu, Dingfei; Schnoor, Jerald L; Mattes, Timothy E

    2014-10-01

    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.

  15. Occurrence and congeners specific of polychlorinated biphenyls in agricultural soils from Southern Jiangsu, China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jian-ying; QIU Li-min; HE Jia; LIAO Yuan; LUO Yong-ming

    2007-01-01

    A total of 198 agricultural soil samples were collected from Zhangjiagang and Changshu in Southern Jiangsu for analysis of 13 polychlorinated biphenyls(PCBs)in order to assess the levels of pollution,sources,area distribution,and potential risk for the environment.All methods were rigorously tested and an adequate quality control was ensured.Only one site had no PCBs residues,and the highest total PCBs concentration in the surface soils was 32.83 ng/g.The average concentration in all the soil samples was 4.13ng/g.signaling low-level pollution.Tetra-,penta-,and hexa-chlorinated biphenyls were dominant speoes in soil samples,accounnng for more than 75%of ΣPCBs in the soil samples.PCB118 was the most abundant congener in all the samples.The PCB118 Was about 20%of ΣPCBs.The soil organic matter content showed only a weak correlation with the levels of all PCB congeners,in which a better correlation was noted for the more volatile lighter PCB congeners than for the heavier homologues.To a certain extent,the sources and land use seemed to influence the levels of PCBs.

  16. Net trophic transfer efficiencies of polychlorinated biphenyl congeners to lake trout (Salvelinus namaycush) from its prey

    Science.gov (United States)

    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.

  17. Net trophic transfer efficiencies of polychlorinated biphenyl congeners to lake whitefish (Coregonus clupeaformis) from their food

    Science.gov (United States)

    Madenjian, C.P.; O'Connor, D.V.; Rediske, R.R.; O'Keefe, J. P.; Pothoven, S.A.

    2008-01-01

    Lake whitefish (Coregonus clupeaformis) were fed rainbow smelt (Osmerus mordax) in four laboratory tanks over a 133-d experiment. At the start of the experiment, 10 to 14 of the fish in each tank were sacrificed, and the concentrations of 40 polychlorinated biphenyl (PCB) congeners within these fish were determined. Polychlorinated biphenyl congener concentrations were also determined in the 15 lake whitefish remaining in each of the four tanks at the end of the experiment as well as in the rainbow smelt fed to the lake whitefish. Each lake whitefish was weighed at the start and the end of the experiment, and the amount of food eaten by the lake whitefish during the experiment was tracked. Using these measurements, net trophic transfer efficiency (??) from the rainbow smelt to the lake whitefish in each of the four tanks was calculated for each of the 40 PCB congeners. Results showed that ?? decreased exponentially as log KOW for the congeners increased from 6 to 8. Further, ?? averaged 0.70 for the tetrachloro congeners but averaged only 0.45 for the higher chlorinated congeners. ?? 2008 SETAC.

  18. Organochlorine compounds in the marine atmosphere of Singapore

    Science.gov (United States)

    Wurl, Oliver; Obbard, Jeffrey Philip

    Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were quantified in high-volume air samples collected on polyurethane foam (PUF) over the sea surface of Singapore during the summer monsoon period of 2004. A novel and quality assured microwave-assisted extraction (MAE) procedure for PUF was developed as an alternative to conventional Soxhlet extraction for the analysis of organochlorine compounds (OCs). Average concentrations of ΣPCBs, ΣHCHs and ΣDDTs in air samples were 32, 311 and 8 pg m -3, respectively. Overall, a decline in the ocean atmospheric concentration of DDTs was noted relative to data obtained from the early 1990s, but current data are in a similar range for HCH and PCBs. Levels of OCs in the equatorial atmosphere were compared to equivalent data from temperate regions available in the literature. On a global scale, the levels of DDTs and PCBs in the atmosphere of Singapore are low, but moderate for HCHs.

  19. Levels of Polychlorinated Dibenzo-p-Dibenzofurans, and Biphenyls in Southern Mississippi Catfish and Estimation of Potential.

    Science.gov (United States)

    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-...

  20. Serum concentrations of polybrominated diphenyl ethers (PBDEs) and a polybrominated biphenyl (PBB) in men from Greenland, Poland and Ukraine

    DEFF Research Database (Denmark)

    Lenters, Virissa; Thomsen, Cathrine; Smit, Lidwien A M;

    2013-01-01

    in Inuit men from across Greenland, and in men from Warsaw, Poland and Kharkiv, Ukraine. Serum was sampled between 2002 and 2004 from men 19 to 50years of age. 299 samples were analyzed for BDE-28, 47, 99, 100, 153, 154 and 183 and the brominated biphenyl BB-153 using gas chromatography-high resolution...

  1. Photochemistry treatment of polychlorinated biphenyls (PCB) in dielectric fluid; Tratamiento fotoquimico de bifenilos policlorados en fluidos dielectricos

    Energy Technology Data Exchange (ETDEWEB)

    Manzano Quinones, M. A. [Escuela Politecnica Superior de Algeciras (Spain)

    2000-07-01

    In this work a study of polychlorinated biphenyls (PCB) photodegradation in dielectric fluid have been done. The experiments has been carried out in a pilot scale photo rector with an ultraviolet light source. The results obtained showed a 92% elimination of PCB following a first kinetic order. In addition the photo reaction products have been identified. (Author) 6 refs.

  2. Impact of polychlorinated biphenyl and polycyclic aromatic hydrocarbon sequestration in sediment on bioaccumulation in aquatic food webs

    NARCIS (Netherlands)

    Moermond, C.T.A.; Roessink, I.; Jonker, M.T.O.; Meijer, T.; Koelmans, A.A.

    2007-01-01

    It is not clear whether sequestration or aging of organic chemicals like polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) limits accumulation in higher levels of aquatic food chains. Therefore, the effect of aging on accumulation was studied in 1-m3 model ecosystems that

  3. First worldwide UNEP interlaboratory study on persistent organic pollutants (POPs) with data on polychlorinated biphenyls and organochlorine pesticides

    NARCIS (Netherlands)

    Leeuwen, van S.P.J.; Bavel, van B.; Boer, de J.

    2013-01-01

    The first worldwide interlaboratory study on persistent organic pollutants (POPs) under the Stockholm Convention was organized, with a participation of 103 laboratories from Asia, Europe, the Americas, Africa and Australia, of which the majority submitted data on polychlorinated biphenyls (PCBs) and

  4. Kinetics and conductivity parameters of uptake and transport of polychlorinated biphenyls in the Caco-2 intestinal cell line model

    NARCIS (Netherlands)

    Dulfer, W.J.; Govers, H.A.J.; Groten, J.P.

    1998-01-01

    Most of the accumulation of polychlorinated biphenyls (PCBs) over the food chain can be attributed to contaminant uptake from food. The effect of fatty acid absorption on net uptake and transport fluxes of a selection of 14 PCBs over the organismal gut epithelium has been determined in monolayers of

  5. Diffusion Coefficients of Polychlorinated Biphenyls and Polycyclic Aromatic Hydrocarbons in Polydimethylsiloxane and Low-Density Polylethylene Polymers

    NARCIS (Netherlands)

    Rusina, T.; Smedes, F.; Klanova, J.

    2010-01-01

    Diffusion coefficients (D) of polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) were determined by film-stacking technique in low-density polyethylene (LDPE) and two types of polydimethylsiloxane (PDMS) (also known as silicone rubber, SR) with the trade names AlteSil (TM)

  6. Plasma polychlorinated biphenyl levels in Dutch preschool children either breast-fed or formula-fed during infancy

    NARCIS (Netherlands)

    Patandin, S; WeisglasKuperus, N; deRidder, MAJ; KoopmanEsseboom, C; vanStaveren, WA; vanderPaauw, CG; Sauer, PJJ

    1997-01-01

    Objectives. This study examined the influence of lactational and in utero exposure to polychlorinated biphenyls (PCBs) on plasma PCB levels in children. Methods. Plasma PCB levels were measured in 173 children at 3.5 years, of whom 91 were breast-fed and 82 were formula-fed in infancy. Results. Medi

  7. Reproductive hormone profile and pubertal development in 14-year-old boys prenatally exposed to polychlorinated biphenyls

    DEFF Research Database (Denmark)

    Grandjean, Philippe; Grønlund, Ciea; Kjær, Ina M;

    2012-01-01

    Because polychlorinated biphenyls (PCBs) are thought to cause endocrine disruption, we examined 438 adolescent boys from a birth cohort in the Faroe Islands, where PCB exposures are elevated. We measured PCBs and p,p'-dichlorodiphenyldichloroethylene (DDE) in cord blood and in serum from clinical...

  8. Polychlorinated biphenyls (PCBs) in indoor air originating from sealants in contaminated and uncontaminated apartments within the same housing estate

    DEFF Research Database (Denmark)

    Frederiksen, Marie; Meyer, Harald William; Ebbehøj, Niels Erik;

    2012-01-01

    Twenty-four congeners of polychlorinated biphenyls (PCBs) were measured in 83 air samples and 20 elastic sealants samples of apartments with PCB-containing sealants. In addition, PCBs were measured in 21 air samples from reference apartments located in an uncontaminated section of the same estate...

  9. Prenatal Exposure to Polychlorinated Biphenyls and Their Hydroxylated Metabolites is Associated with Neurological Functioning in 3-Month-Old Infants

    NARCIS (Netherlands)

    Berghuis, Sietske A.; Soechitram, Shalini D.; Sauer, Pieter J. J.; Bos, Arend F.

    2014-01-01

    Polychlorinated biphenyls (PCBs) are environmental chemicals which are potentially toxic to the developing brain. Their hydroxylated metabolites (OH-PCBs) are suggested to be even more toxic. Knowledge about the health effects of prenatal OH-PCB exposure is limited. We aimed to determine whether pre

  10. 77 FR 12836 - Draft Toxicological Review of Biphenyl: In Support of Summary Information on the Integrated Risk...

    Science.gov (United States)

    2012-03-02

    ... be used to support the first two steps (hazard identification and dose-response evaluation) of the... management decisions designed to protect public health. Dated: February 23, 2012. Darrell A. Winner, Acting... AGENCY Draft Toxicological Review of Biphenyl: In Support of Summary Information on the Integrated...

  11. Poly[(μ4-biphenyl-3,3′-dicarboxylatobis[μ2-1,1′-(butane-1,4-diyldiimidazole](μ2-oxalatodimanganese(II

    Directory of Open Access Journals (Sweden)

    Bao-Yong Zhu

    2010-10-01

    Full Text Available In the title coordination compound, [Mn2(C14H8O4(C2O4(C10H14N42]n, the biphenyl-3,3′-dicarboxylate and oxalate anions, both situated on inversion centres, function in a bridging mode, linking the dinuclear MnII atoms into wave-like layers. Each 1,1′-(1,4-butane-1,4-diyldiimidazole ligand coordinates to two MnII atoms located in adjacent layers via Mn—N coordination bonds, giving a three-dimensional network. As the methylene groups can bend freely relative to each other due to the C atoms connected via single bonds, the 1,1′-(butane-1,4-diyldiimidazole ligand forms an S-shaped conformation, which makes the void in the three-dimensional network distorted.

  12. catena-Poly[[[aquasilver(I]-μ-1,1′-(butane-1,4-diyldi-1H-imidazole-κ2N3:N3′] hemi(biphenyl-4,4′-dicarboxylate dihydrate

    Directory of Open Access Journals (Sweden)

    Zheyu Zhang

    2009-12-01

    Full Text Available In the title compound, {[Ag(C10H14N4(H2O](C14H8O40.5·2H2O}n, the AgI ion is three-coordinated by two N atoms from two independent 1,1′-(butane-1,4-diyldi-1H-imidazole (BBI ligands and one water O atom in a distorted T-shaped coordination geometry. The biphenyl-4,4′-dicarboxylate (BPDC dianions do not coordinate to AgI ions but act as counter-ions. The AgI ions are linked by BBI ligands, forming a zigzag chain. These chains are linked into a two-dimensional supramolecular architecture by O—H...O hydrogen-bonding interactions between water molecules and carboxylate O atoms of the BPDC dianions.

  13. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of organochlorine pesticides and polychlorinated biphenyls in bottom sediment by dual capillary-column gas chromatography with electron-capture detection

    Science.gov (United States)

    Foreman, William T.; Connor, Brooke F.; Furlong, Edward T.; Vaught, Deborah G.; Merten, Leslie M.

    1995-01-01

    A method for the determination of 30 individual organochlorine pesticides, total toxaphene, and total polychlorinated biphenyls (PCBs) in bottom sediment is described. The method isolates the pesticides and PCBs by solvent extraction with dichlorobenzene, removes inorganic sulfur, large naturally occurring molecules, and other unwanted interferences by gel permeation chromatography, and further cleans up and class fractionates the extract using adsorption chromatography. The com- pounds then are instrumentally determined using dual capillary-column gas chromatography with electron-capture detection. Reporting limits range from 1 to 5 micrograms per kilogram for 30 individual pesticides, 50 micrograms per kilogram for total PCBs, and 200 micrograms per kilogram for total toxaphene. The method also is designed to allow the simultaneous isolation of 79 other semivolatile organic compounds from the sediment, which are separately quantified using gas chromatography with mass spectrometric detection. The method was developed in support of the U.S. Geological Survey's National Water-Quality Assessment program.

  14. POLYCHLORINATED DIBENZO-P-DIOXINS, DIBENZOFURANS, AND BIPHENYLS IN FREGATA MAGNIFICENS FROM ILHA GRANDE BAY, RIO DE JANEIRO STATE, SOUTH-EASTERN BRAZIL

    Directory of Open Access Journals (Sweden)

    Aldo Pacheco Ferreira

    2015-03-01

    Full Text Available The purpose of this paper is to perform analyses in a fish-eating seabird species which is recognized to be at risk of accumulating toxic contaminants due to its high position in the trophic web and to its low ability to metabolize xenobiotic compounds. Fregata magnificens were collected at Ilha Grande Bay, Rio de Janeiro, Brazil (23°8'26"S, 44°14'50"W between February, 2009 and April, 2013. Polychlorinated dibenzo-p-dioxins (PCDDs, dibenzofurans (PCDFs, and polychlorinated biphenyls (PCBs, were analyzed in tissue composites, being subsequently identified and quantified using gas chromatography coupled with mass spectrometry. The concentrations were below the range of concern established by World Health Organization. The sum of PCB-congeners analyzed had the concentration of 968 pg/g lipid weight, and 13.9 pg TEQ/g lipid weight. The PCDD/F-congeners analyzed had the concentration of 331.04 pg/g lipid weight, and 13.4 pg TEQ/g lipid weight. This type of study aims to integrate information from analyses of seabirds with halogenated hydrocarbons and could also make contribution to the scientific support for political decisions on coastal zone management.

  15. Enhanced iodide sequestration by 3-biphenyl-5,6-dihydroimidazo 2,1-b thiazole in sodium/iodide sym-porter (NIS)-expressing cells

    Energy Technology Data Exchange (ETDEWEB)

    Lecat-Guillet, N.; Ambroise, Y. [CEA, DSV, Dept Bioorgan Chem andt IsotopLabelling, Inst Biol and Technol, iBiTecS, F-91191 Gif Sur Yvette (France)

    2008-07-01

    The ability of the sodium/iodide sym-porter (NIS) to take up iodide has long provided the basis for cyto-reductive gene therapy and cancer treatment with radio-iodide. One of the major limitations of this approach is that radio-iodide retention in NIS-expressing cells is not sufficient for their destruction. We identified and characterized a small organic molecule capable of increasing iodide retention in HEK293 cells permanently transfected with human NIS cDNA (hNIS-HEK293) and in the rat thyroid-derived cell line FRTL-5. In the presence of 3-biphenyl-4'-yl-5,6-dihydroimidazo[2,1-b)thiazole (ISA1), the transmembrane iodide concentration gradient was increased up to 4.5-fold. Our experiments indicate that the imidazo-thiazole derivative acts either by inhibiting anion efflux mechanisms, or by promoting the relocation of iodide into subcellular compartments. This new compound is not only an attractive chemical tool to investigate the mechanisms of iodide flux at the cellular level, but also opens promising perspectives in the treatment of cancer after NIS gene transfer. (authors)

  16. Investigation of levels in ambient air near sources of Polychlorinated Biphenyls (PCBs) in Kanpur, India, and risk assessment due to inhalation.

    Science.gov (United States)

    Goel, Anubha; Upadhyay, Kritika; Chakraborty, Mrinmoy

    2016-05-01

    Polychlorinated biphenyls (PCBs) are a class of organic compounds listed as persistent organic pollutant and have been banned for use under Stockholm Convention (1972). They were used primarily in transformers and capacitors, paint, flame retardants, plasticizers, and lubricants. PCBs can be emitted through the primary and secondary sources into the atmosphere, undergo long-range atmospheric transport, and hence have been detected worldwide. Reported levels in ambient air are generally higher in urban areas. Active sampling of ambient air was conducted in Kanpur, a densely populated and industrialized city in the Indo-Gangetic Plain, for detection of 32 priority PCBs, with the aim to determine the concentration in gas/particle phase and assess exposure risk. More than 50 % of PCBs were detected in air. Occurrence in particles was dominated by heavier congeners, and levels in gas phase were below detection. Levels determined in this study are lower than the levels in Coastal areas of India but are at par with other Asian countries where majority of sites chosen for sampling were urban industrial areas. Human health risk estimates through air inhalation pathway were made in terms of lifetime average daily dose (LADD) and incremental lifetime cancer risks (ILCR). The study found lower concentrations of PCBs than guideline values and low health risk estimates through inhalation within acceptable levels, indicating a minimum risk to the adults due to exposure to PCBs present in ambient air in Kanpur.

  17. Enhanced phytoremediation potential of polychlorinated biphenyl contaminated soil from e-waste recycling area in the presence of randomly methylated-beta-cyclodextrins.

    Science.gov (United States)

    Shen, Chaofeng; Tang, Xianjin; Cheema, Sardar Alam; Zhang, Congkai; Khan, Muhammad Imran; Liang, Fang; Chen, Xincai; Zhu, Youfeng; Lin, Qi; Chen, Yingxu

    2009-12-30

    The crude recycling of electronic and electric waste (e-waste) is now creating soil pollution problems with organic compounds such as polychlorinated biphenyls (PCBs). The present study aimed to compare the phytoremediation potential of four plant species (rice, alfalfa, ryegrass and tall fescue) for PCBs contaminated soil from Taizhou city, one of the largest e-waste recycling centers in China. In addition, the enhanced effects of randomly methylated-beta-cyclodextrins (RAMEB) on PCBs phytoremediation potential were evaluated. Higher PCBs removal percentages of 25.6-28.5% in rhizosphere soil were observed after 120 days, compared with those of the non-rhizosphere (10.4-16.9%) and unplanted controls (7.3%). The average PCBs removal percentages of four plant species increased from 26.9% to 37.1% in the rhizosphere soil with addition of RAMEB. Meanwhile, relatively high microbial counts and dehydrogenase activity were detected in planted soils and a stimulatory effect by RAMEB addition was found. The present study indicated that all the plant candidates were feasible for phytoremediation of PCBs contaminated soil from the e-waste recycling area, and tall fescue with RAMEB amendment seemed as a promising remediation strategy. High PCBs removal percentage was due to the increased PCBs bioavailability as well as biostimulation of microbial communities after plantation and RAMEB addition.

  18. Enhanced phytoremediation potential of polychlorinated biphenyl contaminated soil from e-waste recycling area in the presence of randomly methylated-{beta}-cyclodextrins

    Energy Technology Data Exchange (ETDEWEB)

    Shen Chaofeng [Institute of Environmental Science and Technology, Zhejiang University, Hangzhou 310029 (China); MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resources Science, Zhejiang University, Hangzhou 310029 (China); Tang Xianjin; Cheema, Sardar Alam; Zhang Congkai; Khan, Muhammad Imran; Liang Fang; Chen Xincai; Zhu Youfeng [Institute of Environmental Science and Technology, Zhejiang University, Hangzhou 310029 (China); Lin Qi, E-mail: linqi@zju.edu.cn [Institute of Environmental Science and Technology, Zhejiang University, Hangzhou 310029 (China); Chen, Yingxu [Institute of Environmental Science and Technology, Zhejiang University, Hangzhou 310029 (China)

    2009-12-30

    The crude recycling of electronic and electric waste (e-waste) is now creating soil pollution problems with organic compounds such as polychlorinated biphenyls (PCBs). The present study aimed to compare the phytoremediation potential of four plant species (rice, alfalfa, ryegrass and tall fescue) for PCBs contaminated soil from Taizhou city, one of the largest e-waste recycling centers in China. In addition, the enhanced effects of randomly methylated-{beta}-cyclodextrins (RAMEB) on PCBs phytoremediation potential were evaluated. Higher PCBs removal percentages of 25.6-28.5% in rhizosphere soil were observed after 120 days, compared with those of the non-rhizosphere (10.4-16.9%) and unplanted controls (7.3%). The average PCBs removal percentages of four plant species increased from 26.9% to 37.1% in the rhizosphere soil with addition of RAMEB. Meanwhile, relatively high microbial counts and dehydrogenase activity were detected in planted soils and a stimulatory effect by RAMEB addition was found. The present study indicated that all the plant candidates were feasible for phytoremediation of PCBs contaminated soil from the e-waste recycling area, and tall fescue with RAMEB amendment seemed as a promising remediation strategy. High PCBs removal percentage was due to the increased PCBs bioavailability as well as biostimulation of microbial communities after plantation and RAMEB addition.

  19. An automated HPLC method for the fractionation of polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins, and polychlorinated dibenzofurans in fish tissue on a porous graphitic carbon column

    Science.gov (United States)

    Echols, Kathy R.; Gale, Robert W.; Tillitt, Donald E.; Schwartz, Ted R.; O'Laughlin, Jerome

    1997-01-01

    The Ah (aryl-hydrocarbon) hydroxylase-receptor active polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were fractionated by an automated high-performance liquid chromatography (HPLC) system using the Hypercarb™ porous graphitic carbon (PGC) column. This commercially available column was used to fractionate the di-, mono-, and non-ortho PCBs into three fractions for gas chromatography (GC)/electron capture detection analysis, and a fourth fraction containing the PCDDs/PCDFs for GC/mass spectrometry analysis. The recoveries of the PCBs ranged from 68 to 96%, and recoveries of the PCDDs/PCDFs ranged from 74 to 123%. The PGC column has the advantage of faster separations (110 min versus 446 min) and less solvent use (275 ml versus 1,100 ml) compared with automated fractionation of these compounds on activated carbon (PX-21), while still affording good separation of the classes. The PGC column may have an advantage over the pyrenyl-based HPLC method because it has a greater loading capacity (400 μg total PCBs versus 250 μg). Overall, the PGC is a standard column that provides reproducible fractionation of PCDD/PCDFs and PCBs for analytical measurement in environmental samples.

  20. Association between exposure to dioxin-like polychlorinated biphenyls and miR-191 expression in human peripheral blood mononuclear cells.

    Science.gov (United States)

    Guida, Maurizio; Marra, Maria Luisa; Marra, Marialuisa; Zullo, Fulvio; Guida, Marco; Trifuoggi, Marco; Biffali, Elio; Borra, Marco; De Mieri, Giovanna; D'Alessandro, Raffaella; De Felice, Bruna

    2013-04-30

    Accumulating evidence shows an association between deregulation of miRNAs and exposure to environmental chemicals; miRNAs play a unique regulatory role in gene expression. Among environmental pollutants, dioxins are a family of compounds that are known to have multiple hazardous effects. Also, in utero exposure of the fetus to dioxins has been shown to cause impaired psychomotor development, decreased immune function and skin disease. miR-191 is a microRNA that has been found to be up-regulated by dioxin in hepatocellular carcinoma cells in vitro. Our study provides the first molecular evidence in vivo of a positive relationship between levels of polychlorinated biphenyls (PCBs) and miR-191 expression in human peripheral blood mononuclear cells. miR-191 expression was significantly correlated with blood concentrations of total PCB and, in particular, of 3,3',4,4',5,5'-hexachlorobiphenyl (PCB 169, a coplanar congener). Blood concentrations of PCB 169 correlated significantly with miR-191 expression in pregnant women living in a PCB-polluted area, who underwent therapeutic abortion due to fetal malformations. These data suggest that miRNAs could be potential biomarkers to clarify the mechanisms of environmental disease.

  1. In vivo genotoxicity of ortho-phenylphenol, biphenyl, and thiabendazole detected in multiple mouse organs by the alkaline single cell gel electrophoresis assay.

    Science.gov (United States)

    Sasaki, Y F; Saga, A; Akasaka, M; Yoshida, K; Nishidate, E; Su, Y Q; Matsusaka, N; Tsuda, S

    1997-12-12

    In Japan, ortho-phenylphenol (OPP), biphenyl (BP), and thiabendazole (2-(4'-thiazolyl)benzimidazole, TBZ) are commonly used as a postharvest treatment to preserve imported citrus fruits during transport and storage. We used a modification of the alkaline single cell gel electrophoresis (SCG) (Comet) assay to test the in vivo genotoxicity of those agents in mouse stomach, liver, kidney, bladder, lung, brain, and bone marrow. CD-1 male mice were sacrificed 3, 8, and 24 h after oral administration of the test compounds. OPP (2000 mg/kg) induced DNA damage in the stomach, liver, kidney, bladder, and lung, BP (2000 mg/kg) and TBZ (200 mg/kg) induced DNA damage in all the organs studied. For OPP, increased DNA damage peaked at 3-8 h and tended to decrease at 24 h. For BP, on the contrary, increased DNA migration peaked at 24 h. That delay may have been due to the fact that OPP is metabolized by cytochrome 450 and prostaglandin H synthase to phenylbenzoquinone (PBQ), a DNA binding metabolite, and BP is metabolized to PBQ via OPP and m-phenylphenol. The positive response to TBZ, an aneugen, supports the in vivo DNA-damaging action of TBZ.

  2. Crystal structure of (E-1-(4′-methoxy-[1,1′-biphenyl]-4-yl-3-(3-nitrophenylprop-2-en-1-one

    Directory of Open Access Journals (Sweden)

    T. Vidhyasagar

    2015-01-01

    Full Text Available The title compound, C22H17NO4, crystallizes with two independent molecules (A and B in the asymmetric unit. Each molecule exists as an E isomer with C—C=C—C torsion angles of −175.69 (17 and −178.41 (17° in A and B, respectively. In molecule A, the planes of the terminal benzene rings are twisted by an angle of 26.67 (10°, while the biphenyl unit is non-planar, the dihedral angle between the rings being 30.81 (10°. The dihedral angle between the nitrophenyl ring and the inner phenyl ring is 6.50 (9°. The corresponding values in molecule B are 60.61 (9, 31.07 (8 and 31.05 (9°. In the crystal, molecules are arranged in a head-to-head manner, with the 3-nitrophenyl groups nearly parallel to one another. The A and B molecules are linked to one another via C—H...O hydrogen bonds, forming chains lying parallel to (-320 and enclosing R22(10 and R22(12 ring motifs. The methoxy group in both molecules is positionally disordered with a refined occupancy ratio of 0.979 (4:0.021 (4 for molecule A and 0.55 (4:0.45 (4 for molecule B.

  3. Blood levels of polychlorinated biphenyls and their hydroxylated metabolites in Baikal seals (Pusa sibirica): emphasis on interspecies comparison, gender difference and association with blood thyroid hormone levels.

    Science.gov (United States)

    Imaeda, Daisuke; Nomiyama, Kei; Kunisue, Tatsuya; Iwata, Hisato; Tsydenova, Oyuna; Amano, Masao; Petrov, Evgeny A; Batoev, Valeriy B; Tanabe, Shinsuke

    2014-11-01

    We have previously demonstrated that Baikal seals (Pusa sibirica) are still being exposed to polychlorinated biphenyls (PCBs), and the population is at risk. In the present study, we measured the residue levels of PCBs and their hydroxylated metabolites (OH-PCBs) in the blood of Baikal seals and assessed the impact of OH-PCBs on the thyroid function. Blood concentrations of PCBs and OH-PCBs were in the range of 2.8-130 ng g(-1)wet wt. and 0.71-4.6 ng g(-1)wetwt., respectively. Concentrations of higher-chlorinated OH-PCBs (hexa- to octa-PCBs) were more than 70% to total OH-PCB concentrations, indicating Baikal seals are mostly risked by higher-chlorinated OH-PCBs. High levels of 4OH-CB146 and 4OH-CB187 and low levels of 4OH-CB107/4'OH-CB108 found in Baikal seals were different from those in other phocidae species, suggesting the unique drug-metabolizing enzyme activities and/or contamination sources in this species. Concentrations of some OH-PCBs in males were significantly higher than those in females. These results suggest that these isomers may be preferentially transferred from mother to pup via cord blood. However, concentrations of almost all the isomers were not significantly correlated with the levels of blood total T3 and T4, implying less impact of PCB-related compounds on the thyroid hormone circulation.

  4. Distribution of free radicals and intermediates during the photodegradation of polychlorinated biphenyls strongly affected by cosolvents and TiO₂ catalyst.

    Science.gov (United States)

    Zhu, Xiangdong; Wang, Yujun; Qin, Wenxiu; Zhang, Shicheng; Zhou, Dongmei

    2016-02-01

    Polychlorinated biphenyls (PCBs) pose potential ecological risk because of their high toxicity and carcinogenicity. Photodegradation, which is an important process for the removal of PCBs, is greatly influenced by the cosolvent and catalyst. Hence, it is important to explore their effects on the photodegradation behavior of PCBs. In this study, 2,4,4'-trichlorobiphenyl (PCB28) was selected as a model compound, and the effects of two typical cosolvents, namely acetone and ethanol, and TiO2 catalyst on the distributions of free radicals and intermediates were investigated. Interestingly, the TiO2 catalyst did not promote PCB28 photodegradation. Moreover, the free radical distribution was greatly influenced in the presence of the TiO2 catalyst, while was only slightly affected in its absence by the cosolvent kinds. The main photodegradation pathways are proposed on the basis of the distribution of detected intermediates, which were significantly regulated by both the cosolvent and TiO2 catalyst. The results provide novel insights into the photodegradation of PCBs and may have important implications for choosing cosolvent in desorbing soil PCBs and consequently enhancing PCBs degradation.

  5. Brominated flame retardants and polychlorinated biphenyls in human breast milk from several locations in India: potential contaminant sources in a municipal dumping site.

    Science.gov (United States)

    Devanathan, Gnanasekaran; Subramanian, Annamalai; Sudaryanto, Agus; Takahashi, Shin; Isobe, Tomohiko; Tanabe, Shinsuke

    2012-02-01

    This study investigated the status of contamination of organohalogen compounds (OCs) such as polychlorinated biphenyls (PCBs) and brominated flame retardant (BFRs), including polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs) in human milk samples from several locations in India. The levels of OCs were significantly higher in the milk of mothers living in and near municipal dumping site than other locations indicating that the open dumping sites for municipal wastes act as potential sources of these contaminants in India. The PCB concentrations observed in this study tended to decrease compared to those in the matched locations reported previously, probably due to the restriction of technical PCB usage in India. PBDE levels in human milk were two to three folds lower than those of PCBs in all the sampling locations investigated. Congener profiles of PCBs and PBDEs were different between samples from the dumping site mothers and general populations in other areas suggesting the presence of region-specific sources and pathways. HBCDs were detected in human milk from only two sites, with much lower concentrations and detection frequencies compared to PCBs and PBDEs. When hazard quotients (HQs) of PCBs and PBDEs were estimated for infant health risk, the HQs in some milk samples from the dumping site exceeded the threshold value (HQ>1) of PCBs, indicating the potential risk for infants in the specific site.

  6. Content of polychlorinated dibenzo-p-dioxins, dibenzofurans and dioxin-like polychlorinated biphenyls in fish from Latvian lakes.

    Science.gov (United States)

    Zacs, D; Bartkevics, V; Viksna, A

    2013-04-01

    Seventeen polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/PCDFs) of the highest priority as well as twelve dioxin-like polychlorinated biphenyls (dl-PCBs) were analyzed in the muscle tissues of the following freshwater fish species sampled from eleven Latvian freshwater lakes: perch (Perca flavescens), carp (Cyprinus carpio), eel (Anguilla rostrata), bream (Abramis brama), chub (Leuciscus cephalus), pike (Esox lucius), sheatfish (Silurus glanis) and roach (Rutilus). To analyze the selected persistent organic pollutants in fish matrices, an optimization of EPA-1613 and EPA-1668A clean-up procedures was carried out, followed by validation of the analytical procedure according to Commission Regulation (EC) No 1883/2006. The adopted analytical procedure was in compliance with requirements of the more recent Commission Regulation (EU) No 252/2012. Modifications of carbon column chromatography clean-up and separation steps were used for treatment of the fish samples. Other clean-up procedure stages were performed according to the methods EPA-1613 and EPA-1668A and involved gel permeation chromatography (GPC), as well as manual acidic silica and Florisil column chromatography for purification and fractionation of the samples. An isotope dilution method was used for the qualitative and quantitative determination of individual congeners. Analytes of interest were separated and detected using gas chromatography - high resolution mass spectrometry. The concentration of PCDD/PCDFs and dl-PCBs in freshwater fish and eel samples ranged from 0.05 to 8.0 pg WHO(1998)-PCDD/PCDF-PCB-TEQ g(-1) fresh weight. These levels are below the EU maximum permissible limits although calculation of the content of these compounds relative to the weight of fat shows contamination levels similar to those found in Baltic herring and sprats, that are known to be highly contaminated. A difference in congener pattern between the Baltic Sea fish and freshwater fish was detected

  7. 3D multidisciplinary numerical model of polychlorinated biphenyl dynamics on the Black Sea north-western shelf

    Science.gov (United States)

    Bagaiev, Andrii; Ivanov, Vitaliy

    2014-05-01

    The Black Sea north-western shelf plays a key role in economics of the developing countries such as Ukraine due to food supply, invaluable recreational potential and variety of the relevant maritime shipping routes. On the other hand, a shallow flat shelf is mostly affected by anthropogenic pollution, eutrophication, hypoxia and harmful algae blooms. The research is focused on modeling the transport and transformation of PCBs (PolyChlorinated Biphenyls) because they are exceedingly toxic and highly resistant to degradation, hence cumulatively affect marine ecosystems. Being lipophilic compounds, PCBs demonstrate the distinguishing sorption/desorption activity taking part in the biogeochemical fluxes via the organic matter particles and sediments. In the framework of the research, the coastal in-situ data on PCB concentration in the water column and sediments are processed, visualized and analyzed. It is concluded that the main sources of PCBs are related to the Danube discharge and resuspension from the shallow-water sediments. Developed 3D numerical model is aimed at simulation of PCB contamination of the water column and sediment. The model integrates the full physics hydrodynamic block as well as modules, which describe detritus transport and transformation and PCB dynamics. Three state variables are simulated in PCB transport module: concentration in solute, on the settling particles of detritus and in the top layer of sediments. PCB adsorption/desorption on detritus; the reversible PCB fluxes at the water-sediment boundary; destruction of detritus are taken into consideration. Formalization of PCB deposition/resuspension in the sediments is adapted from Van Rijn's model of the suspended sediment transport. The model was spun up to reconstruct the short term scenario of the instantaneous PCB release from the St. George Arm of Danube. It has been shown that PCB transport on sinking detritus represents the natural buffer mechanism damping the spreading PCB

  8. 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

    Directory of Open Access Journals (Sweden)

    Claudia Zani

    2013-05-01

    Full Text Available 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 dia- betes 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.

  9. Research advances in microbial dechlorination of polychlorinated biphenyls%多氯联苯微生物脱氯研究进展

    Institute of Scientific and Technical Information of China (English)

    陈晨; 崔静岚; 秦智慧; 俞春娜; 陈曦; 沈超峰; 陈英旭

    2012-01-01

    Polychlorinated biphenyls ( PCBs) are the typical persistent organic pollutants ( POPs) in the environment. As a ubiquitous attenuation course of chlorinated organic compounds in anoxic environment, the microorganism-mediated reductive dechlorination process plays an important role in PCBs transformation, especially the transformation of higher chlorinated PCBs. The higher chlorinated PCBs can be dechlorinated in anaerobic condition, and thus, their persistence and toxicity can be decreased. The resultant lower chlorinated PCBs from the dechlorination can be further degraded and completely mineralized in aerobic condition. This paper summarized the research advances of PCBs microbial reductive dechlorination, introduced the mechanisms and characteristics of the dechlorination and the related specific microorganisms, and approached the affecting factors of PCBs bio-dechlorination, as well as the significances of anaerobic dechlorination coupling with aerobic degradation. The future research directions, including the complex metabolic networks of dechlorinating microbial populations, the screening of novel specific dechlorinators and their practical applications in the remediation of PCBs contaminated sites were also prospected.%多氯联苯(polychlorinated biphenyls,PCBs)是环境中典型的氯代持久性有机污染物.微生物脱氯是一种氯代有机物自然降解模式,对全球PCBs特别是高氯代同系物消减起到至关重要的作用.厌氧条件下高氯代PCBs能够发生脱氯反应,使其毒性大大降低,脱氯后形成的低氯代化合物可以进一步好氧降解,直至完全矿化.本文综述了PCBs生物脱氯的研究进展,介绍了微生物脱氯反应的机理和特征、参与微生物脱氯过程的专性脱氯菌等,探讨了该微生物过程的影响因素及厌氧脱氯与好氧降解耦合的意义,并对脱氯微生物群落的复杂代谢网络研究、专性脱氯新菌种筛选及其污染地实际修复应用等未来研究方向进行了展望.

  10. Synthesis and Characterization of a Novel Copoly(aryl ether ketone) Containing 4, 4'-Biphenyl-bis[4-phthalazin-1(2H)-one] Moiety

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A new monomer of 4, 4'-biphenyl-bis[4-phthalazin-1(2H)-one] was synthesized from biphenyl and phthalic anhydride, and a novel copoly(aryl ether ketone) (PPEK) was synthesized from 2, 2-bis(4-hydroxyphenyl)-propane (BPA), 4, 4'-biphenyl-bis-[4-phthalazin-1(2H)-one], 4, 4'- difluorodiphenylketone (DFK). The monomer and copolymer were characterized by FT-IR and 1H-NMR. DSC and TGA were used to the novel polymer.

  11. Concentrations of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and dioxin-like polychlorinated biphenyls in blood and breast milk collected from 60 mothers in Sapporo City, Japan.

    Science.gov (United States)

    Todaka, Takashi; Hirakawa, Hironori; Kajiwara, Jumboku; Hori, Tsuguhide; Tobiishi, Kazuhiro; Onozuka, Daisuke; Kato, Shizue; Sasaki, Seiko; Nakajima, Sonomi; Saijo, Yasuaki; Sata, Fumihiro; Kishi, Reiko; Iida, Takao; Furue, Masutaka

    2008-07-01

    We measured the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), non-ortho polychlorinated biphenyls (non-ortho PCBs), and mono-ortho polychlorinated biphenyls (mono-ortho PCBs) in paired samples of blood and breast milk collected from 60 mothers in Sapporo City, Hokkaido Prefecture, Japan. The present study is one of the few studies in which PCDDs, PCDFs, and dioxin-like PCBs have been measured in blood and breast milk collected from 60 same mothers. Of these 60 mothers, 30 were primipara (mean: 30.1 years, median: 28.0 years) and 30 were multipara (mean: 32.2 years, median: 32.5 years). The arithmetic mean TEQ concentrations of PCDDs, PCDFs, non-ortho PCBs, and mono-ortho PCBs in blood and breast milk of the primiparous mothers were 9.0, 3.3, 5.7, and 0.4 pg TEQ g(-1) lipid, respectively, and 5.2, 2.2, 4.5, and 0.4 pg TEQ g(-1) lipid, respectively, with the total TEQ concentrations of these dioxin-like compounds being 9.3-42.9 (mean: 18.4, median: 17.3) and 7.0-41.1 (mean: 12.3, median: 11.4) pg TEQ g(-1) lipid, respectively. In the case of multiparous mothers, the arithmetic mean TEQ concentrations of these dioxin-like compounds in blood and breast milk were 7.1, 2.7, 5.3, and 0.4 pg TEQ g(-1) lipid, respectively, and 3.9, 1.7, 3.8, and 0.4 pg TEQ g(-1) lipid, respectively, with the total TEQ concentrations being 3.4-28.1 (mean: 15.5, median: 13.9) and 2.7-20.0 (mean: 9.8, median: 9.2)pg TEQ g(-1) lipid, respectively. The total TEQ concentrations of PCDDs, PCDFs, non-ortho PCBs, and mono-ortho PCBs in blood and breast milk of primiparous mothers in Sapporo City appeared to be generally lower than those recently surveyed throughout the greater area of Japan. Significant correlations were observed between age and the total TEQ concentrations of PCDDs, PCDFs, non-ortho PCBs, and mono-ortho PCBs in the blood of primiparae and multiparae, and significant correlations were also observed between age and the total TEQ

  12. Isolation of high efficient biphenyl-biodegrading strain and its characteristics%高效联苯降解菌的筛选及其特性

    Institute of Scientific and Technical Information of China (English)

    吴晓琴; 张梦思; 周卫; 魏仁零

    2012-01-01

    Coking wastewater is refractory biodegraded industrial wastewater containing high concentration organics.Of the organics,polycyclic aromatic hydrocarbons(PAHs) is one of refractory biodegraded pollutants,and will hazard the environment greatly.A method of bioaugmentation for efficient PAHs biodegradation was studied.Biphenyl was a model compound selected as a unique carbon source for microbes screening.Six strains of microbes were isolated from coking wastewater and sludge by biological selective culture and multistage accumulation.WIS-01 was the most efficient one selected by the method of acclimation with a step up toxic load.Identification,growth and biphenyl-degradation of WIS-01 were studied further.Experimental results indicate that the degradation rate of WIS-01 could reach to 99% in three days.And its maximum tolerated concentration of biphenyl is 2 g/L.The colony of WIS-01 is Pseudomonas identified by 16S rDNA sequence,morphological,biochemical and physiological experiments,and it shares the homology up to 95%.%焦化废水属高浓度难降解工业有机废水,其中所含的多环芳烃属难降解有机物,且对环境产生毒害作用。为探索生物强化技术去除焦化废水中多环芳烃类化合物,采用选择性培养和多级富集的方法,以联苯为模型化合物,并作为惟一碳源,从焦化厂废水和污泥中分离和筛选得到6株联苯降解菌。通过逐渐提高底物浓度的方法驯化菌株后,从中筛选出降解效率最高的联苯降解菌株WIS-01,在此基础上进行菌属鉴定、细菌生长情况及联苯降解性能的研究。实验结果表明,3 d内菌株WIS-01对联苯的降解率可达99%以上,可耐受联苯的最高质量浓度为2 g/L。通过形态学、生理生化鉴定和16S rDNA序列比对分析,确定菌株WIS-01属于假单胞菌属,同源性达95%,命名为Pseudomonas sp.WIS-01。

  13. Studies on the Quantitative Structure-activity Relationship of Substituted Biphenyls by Density Function Theory (DFT)

    Institute of Scientific and Technical Information of China (English)

    HAN Xiang-Yun; ZHENG Qing

    2007-01-01

    Geometrical configurations of 16 substituted biphenyls were computed at the B3LYP/6-311G** level with Gaussian 98 program. Based on linear solvation energy theory, lgKow as well as the structural and thermodynamic parameters obtained at this level was taken as theoretical descriptors, and corresponding equation predicting the toxicity of Daphnia magna (-lgEC50)was thus obtained, in which three parameters were contained, i.e., n-octanol/water partition coefficients (lgKow), dipole moment of the molecules (μ) and entropy (S°). For this equation, R2 =0.9582, q2 = 0.8921 and SD = 0.102. The absolute t-scores of three variables are larger than the standard one in the confidence range of 95%, which confirms the creditability and stability of this model.

  14. Problems with the polychlorinated biphenyls (PCB) in Mexico; Problematica de los bifenilos policlorados (BPC) en Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Valle, Esteban; Cruz, Maria Guadalupe [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1997-12-31

    A general overview is presented of the problems with the polychlorinated biphenyls (PCB) (askarels) in Mexico, which are mainly associated with the use of these substances in electric equipment; also, a profile of the causes why the PCBs have been classified as environmental toxic substances and a potential hazard for the health of human beings. [Espanol] Se presenta un panorama general de la problematica de bifenilos policlorados (BPC) (askareles) en Mexico, la cual esta asociada principalmente con el uso de estos compuestos en equipos electricos; asimismo, se describe una semblanza de las causas por las cuales se han catalogado a los BPC como sustancias toxicas ambientales y un peligro potencial para la salud de los seres humanos.

  15. Accumulation and depletion of polychlorinated biphenyl (PCB) congeners in the housefly (musca domestica, L. )

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, L.G. (Univ. of Illinois, Urbana (United States)); Storr-Hansen, E. (National Environmental Research Inst., Soeborg (Denmark))

    1992-01-01

    Polychlorinated biphenyl (PCB) residues in food chains and in the environment are dynamic complex mixtures and there is considerable interest in the disposition as well as toxicities of individual congeners. The persistence and biological activities of PCBs are intimately associated with microsomal monooxygenases. The house fly, Musca domestica (L.), has long been a standard organism for studies of pesticide toxicology and has an active and well-defined microsomal monooxygenase system. These oxidases in the fly can be induced by PCBs. It was considered of interest to provide data which may indicate whether or not the relatively large and mobile biomass of insects in general may play a role in the global disposition of PCBs. It was also of interest to determine if the house fly could serve as a model for determining the relative accumulation, elimination, and toxicities of individual PCB congeners.

  16. Polychlorinated biphenyls in fresh and canned fish from the Central Adriatic.

    Science.gov (United States)

    Kipcić, D; Vukusić, J

    1991-01-01

    By using the GLC method, levels of polychlorinated biphenyls (PCBs) were determined in fresh and canned fish during the 1984-88 period. Forty-six samples of fish caught in the Central Adriatic's littoral, 11 of which in a control, non-industrialized area, and 35 in an urbanized area strongly affected by industry, were collected. Also, 101 samples of canned fish were tested for PCBs. The average PCB values were 0.059 mg kg-1 and 0.287 mg kg-1 in control and polluted areas, respectively; the mean value in canned fish was 0.194 mg kg-1. Although the levels of PCBs in control and industrialized areas were found to differ, the difference was not significant statistically.

  17. Evaluating daily exposure to polychlorinated biphenyls and polybrominated diphenyl ethers in fish oil supplements.

    Science.gov (United States)

    Ashley, J T F; Ward, J S; Schafer, M W; Stapleton, H M; Velinsky, D J

    2010-08-01

    Fish oil supplements have become a popular means of increasing one's dietary intake of essential polyunsaturated fatty acids. However, there is growing concern that the levels and potential health effects of lipophilic organic contaminants such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) may diminish some of the health benefits associated with the daily consumption of fish oil supplements. In this study, ten over-the-counter fish oil supplements available in the United States were analysed for PCBs and PBDEs and daily exposures calculated. Based on manufacturers' recommended dosages, daily intakes of PCBs and PBDEs ranged from 5 to 686 ng day(-1) and from 1 to 13 ng day(-1), respectively. Daily consumption of fish oil supplements expose consumers to PCBs and PBDEs. However, in comparison with fish ingestion, fish supplements may decrease daily PCB exposure and provide a safer pathway for individuals seeking to maintain daily recommended levels of polyunsaturated fatty acids.

  18. Exposure to 27 polychlorinated biphenyls in the indoor environment of a workplace

    DEFF Research Database (Denmark)

    Pedersen, Ellen Bøtker; Ebbehøj, N E; Göen, T

    2016-01-01

    PURPOSE: To assess the exposure to a broad-spectrum of polychlorinated biphenyl congeners (PCBs) from the indoor environment through bio-monitoring of people working in a building with PCB-containing materials and elevated PCB levels in the indoor air. METHODS: A cross-sectional study comparing...... the plasma concentration of 27 PCB congeners in 15 people working in a PCB-contaminated building and 30 matched controls. RESULTS: Median concentration of eight low-chlorinated PCB congeners was significantly higher in the exposed than in the control group. The sum of median concentrations of tri + tetra......-chlorinated PCB was almost ten times higher in the exposed group than in the unexposed, and sums of dioxin-like and non-dioxin-like PCB were both relatively increased by 60 % in the exposed group. CONCLUSIONS: The occupational indoor environment may significantly add to PCB exposure, especially to the lower...

  19. Preparation and characterization of gold nanoparticles capped by peptide-biphenyl hybrids.

    Science.gov (United States)

    Pérez, Yolanda; Mann, Enrique; Herradón, Bernardo

    2011-07-15

    Gold nanoparticles were prepared using peptide-biphenyl hybrids (PBHs) as capping agents. AuNPs were characterized by different techniques including UV-Vis, TEM, EDX, FT-IR, elemental analysis, (1)H NMR and (13)C CP/MAS NMR spectroscopy. TEM analysis showed that AuNPs present diameters in the range of 1.8-3.7 nm, depending on the structure and the amount of the capping PBH used. FT-IR spectroscopy and solid-state (13)C NMR revealed that the carboxylic group of PBHs, especially in the case of the acid ligands, interacts with the gold surface (in the form of carboxylate). The results confirm that PBHs are excellent stabilizers of AuNPs, being one of the first examples on the use of peptidomimetics-gold hybrid materials.

  20. Contamination of soil, leaves and vegetables by polychlorinated biphenyls in Xiamen region, China

    Institute of Scientific and Technical Information of China (English)

    MASKAOUI Khalid; ZHOU Jun-liang; HAN Ya-li; HU Zhong; ZHENG Tian-ling; HONG Hua-sheng

    2005-01-01

    The paper aimed to identify the primary of polychlorinated biphenyls(PCBs) in the diulong River Estuary, investigate the spatial distribution of PCBs contamination in the environment, localize the atmospheric source and evaluate ongoing PCBs emissions by analyzing soil samples collected along the Jiulong River region. In addition, the accumulation of PCBs in the human food chain was quantified by analyzing leaf of orange trees and vegetable samples collected along a gradient of soil/atmospheric contamination moving away from the source. Consequently, the impact on the human health and the ecosystem was quantified, different management options were proposedto reduce this impact and to carry out research on organic contaminants along the Jiulong River and Xiamen region.

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

    Science.gov (United States)

    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.

  2. Polychlorinated biphenyl toxicity to Japanese quail as related to degree of chlorination

    Science.gov (United States)

    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.

  3. Effects of pesticides, polychlorinated biphenyls and metals on the growth and reproduction of Acanthamoeba castellanii

    Energy Technology Data Exchange (ETDEWEB)

    Prescott, L.M.; Kubovec, M.K.; Tryggestad, D.

    1977-07-01

    The effects of pollutants (pesticides, PCB and metals) were studied in the free-living amoeba, Acanthamoeba castellanii. Eight pesticides were used--the insecticides dieldrin, aldrin and sevin, and the herbicides linuron, stam F-34, IPC, atrazine and simazine. It was shown that the sensitivity of A. castellanii to pesticides varied greatly. The population growth was inhibited by linuron, stam F-34, IPC, sevin and atrazine at a level of 10 mg/l. The polychlorinated biphenyl, Arochor 1254, had no significant effect at a concentration of 0.01 mg/l (10 ppb). The studies with metal ions showed that A. castellanii was unaffected by moderately high levels of Cu and Zn, but was sensitive to the presence of Pb and mercuric ions.

  4. Effect of polychlorinated biphenyls on spermatogenesis and testosterone secretion in adult cocks

    Institute of Scientific and Technical Information of China (English)

    张才乔; 乔惠理

    2004-01-01

    The effects ofpolychlorinated biphenyls (PCBs) on reproduction of adult cocks were studied by gavaging peanut oil or PCBs (Aroclor 1254, 50 mg/kg) once a week for six consecutive weeks. Physiological parameters were recorded and gonads were removed at the end of experiment for histological examination. The results showed that there was no significant difference between the control and treatment group in body weight, respiration rate, heart rate, body temperature, and the numbers of red and white blood cells. However, there was a marked decrease in the testicular weight and serum testosterone level after PCB treatment. Morphological studies manifested severe damage of the seminiferous tubules by PCB. The number of the germ cells at the different developmental stages was decreased and condensed nuclei were observed in most of these cells. This study revealed that the reproductive function of the adult cocks is sensitive to PCBs, which inhibited mainly spermatogenesis and testosterone secretion.

  5. Rhizospere Redox Cycling and Implications for Rhizosphere Biotransformation of Selected Polychlorinated Biphenyl (PCB) Congeners.

    Science.gov (United States)

    Meggo, Richard E; Schnoor, Jerald L

    2013-08-01

    Theoretically, sequential cycles of dechlorination followed by aerobic bio-oxidation are desirable to achieve complete degradation of a mixture of higher and lower chlorinated PCBs. In this research, soil was artificially contaminated with polychlorinated biphenyls (PCBs) in mixture and as single congeners, aged, and planted with two different plant species. Alternating redox cycles were created in the root zone of plants by flooding and draining the soil. Over 32 weeks, switchgrass (Panicum virgatum) and poplar (Populus deltoids x nigra DN34) planted systems that were exposed to alternate cycles of flooding performed better in reducing parent PCBs than planted systems that were not cycled (p<0.05). The cycled systems also had a higher mass of PCB transformation products than the uncycled systems. Multiple cycles were necessary to achieve significant differences between the cycled and uncycled treatments.

  6. Studies on biphenyl disulphonic acid doped polyanilines: Synthesis, characterization and electrochemistry

    Indian Academy of Sciences (India)

    Chepuri R K Rao; R Muthukannan; M Vijayan

    2012-06-01

    In this article, we report on the results obtained for the efforts we made to bring processability to the conducting polyaniline and substituted polyanilines by designing and synthesizing a new disulphonic acid with a biphenyl moiety as spacer group, viz. 4,4'-biphenyldisulphonic acid (BPSA). When doped, the disulphonic acid acts as a spacer group between the polyaniline chains and facilitates increase in solubility and conductivity. The spacing effect is maximized when BPSA is used as doping agent in in situ polymerization reactions. The conductivity of polyaniline doped by BPSA is 4 S/cm and for the substituted polyanilines it ranged from 2 × 10-5 to 8 × 10-4 S/cm.

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

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    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.

  8. Prospects for using combined engineered bacterial enzymes and plant systems to rhizoremediate polychlorinated biphenyls.

    Science.gov (United States)

    Sylvestre, Michel

    2013-03-01

    The fate of polychlorinated biphenyls (PCBs) in soil is driven by a combination of interacting biological processes. Several investigations have brought evidence that the rhizosphere provides a remarkable ecological niche to enhance the PCB degradation process by rhizobacteria. The bacterial oxidative enzymes involved in PCB degradation have been investigated extensively and novel engineered enzymes exhibiting enhanced catalytic activities toward more persistent PCBs have been described. Furthermore, recent studies suggest that approaches involving processes based on plant-microbe associations are very promising to remediate PCB-contaminated sites. In this review emphasis will be placed on the current state of knowledge regarding the strategies that are proposed to engineer the enzymes of the PCB-degrading bacterial oxidative pathway and to design PCB-degrading plant-microbe systems to remediate PCB-contaminated soil.

  9. Polychlorinated biphenyl exposure and glucose metabolism in Danish children aged 9 years

    DEFF Research Database (Denmark)

    Jensen, Tina K; Timmermann, Clara Amalie Gade; Rossing, Laura I;

    2014-01-01

    and participants: A total of 771 healthy Danish third grade school children aged 8-10 years in the municipality of Odense were recruited in 1997 through a two-stage cluster sampling from 25 different schools stratified according to location and socioeconomic character; 509 (9.7±0.8 years, 53% girls) had adequate......Context: Human exposure to polychlorinated biphenyls (PCBs) has been associated to type 2 diabetes in adults. Objectives: To determine whether concurrent serum PCB concentration was associated with markers of glucose metabolism in healthy children. Design: Cross-sectional study. Settings......-DDE. Conclusion: A strong inverse association between serum insulin and PCB exposure was found while fasting plasma glucose remained within the expected narrow range. Our findings suggest that PCB may not exert effect through decreased peripheral insulin sensitivity, as seen in obese and low fit children...

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

    Directory of Open Access Journals (Sweden)

    Mircea V. Diudea

    2006-11-01

    Full Text Available The paper presents a unitary approach of the use of a Molecular DescriptorsFamily in structure-property/activity relationships, particularly in modelling thechromatographic retention times of polychlorinated biphenyls. Starting from molecularstructure, viewed as a graph, and considering the bonds and bond types, atom types andoften the 3D geometry of the molecule, a huge family of molecular descriptors called MDFwas calculated. A preliminary selection of MDF members was done by simple linearregression (LR against the measured property. The best fitted MDF subset is thensubmitted to multivariate linear regression (MLR analysis in order to find the best pairs ofMDF members that produce a reliable QSPR (Quantitative Structure-PropertyRelationship model. The predictive capability was finally tested by randomly splitting ofdata into training and test sets. The best obtained models are presented and the results arediscussed.

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

    Science.gov (United States)

    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).

  12. Improved extraction procedures for polychlorinated biphenyls in solid samples with aqueous sodium hydroxide under autoclave conditions.

    Science.gov (United States)

    Akimoto, Y; Inouye, Y

    2000-03-01

    The efficacy of the extraction of polychlorinated biphenyls (PCBs) from varnish-infiltrated insulating papers as a model of solid materials with an aqueous sodium hydroxide (NaOH) by autoclaving at 121 degrees C for 30 min was compared with those for the conventional procedures, i.e., saponification with 1 N ethanolic NaOH in a boiling water bath for 60 min and extraction with benzene in a Soxhlet apparatus. The newly invented autoclaving method was found to be superior to the conventional ones, yielding approximately 5- to 6-fold cumulative PCB congeners without being accompanied by extended decomposition. Therefore, the autoclave-based sample treatment is recommended for more accurate determination of PCBs in the case of PCB-impregnated solid materials such as hardened oils and resin-coated or -infiltrated papers instead of being treated conventionally.

  13. Modelling the impact of room temperature on concentrations of polychlorinated biphenyls (PCBs) in indoor air

    DEFF Research Database (Denmark)

    Lyng, Nadja; Clausen, Per Axel; Lundsgaard, Claus;

    2016-01-01

    Buildings contaminated with polychlorinated biphenyls (PCBs) are a health concern for the building occupants. Inhalation exposure is linked to indoor air concentrations of PCBs, which are known to be affected by indoor temperatures. In this study, a highly PCB contaminated room was heated to six...... temperature levels between 20 and 30 C, i.e. within the normal fluctuation of indoor temperatures, while the air exchange rate was constant. The steady-state air concentrations of seven PCBs were determined at each temperature level. A model based on Clausius–Clapeyron equation, ln(P) = −H/RT + a0, where...... changes in steady-state air concentrations in relation to temperature, was tested. The model was valid for PCB-28, PCB-52 and PCB-101; the four other congeners were sporadic or non-detected. For each congener, the model described a large proportion (R2>94%) of the variation in indoor air PCB levels...

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

    Science.gov (United States)

    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.

  15. Polychlorinated biphenyls removal from contaminated soils using a transportable indirect thermal dryer unit: implications for emissions.

    Science.gov (United States)

    Yang, Bing; Xue, Nandong; Ding, Qiong; Vogt, Rolf David; Zhou, Lingli; Li, Fasheng; Wu, Guanglong; Zhang, Shilei; Zhou, Dandan; Liu, Bo; Yan, Yunzhong

    2014-11-01

    An assessment in China of the application of a transportable indirect thermal dryer unit for the remediation of soils contaminated with polychlorinated biphenyls (PCBs) demonstrated that it is well suited to remove PCBs from soils. A remarkable reduction of total PCBs in soils from 163-770 μg g(-1) to 0.08-0.15 μg g(-1) was achieved. This represented removal efficiencies of greater than 99.9% and an approximate 100% removal of the toxic equivalent of the PCBs. Furthermore, the emissions to the atmosphere from the unit were in compliance with current PCBs regulations. In conclusion, remediation of PCBs-contaminated soils based on a transportable indirect thermal dryer unit appears to be a highly efficient and environmentally sound treatment technology that has huge implications for cleaning thousands of regionally dispersed sites of PCBs contamination in China.

  16. QSAR studies of bioconcentration factors of polychlorinated biphenyls (PCBs) using DFT, PCS and CoMFA.

    Science.gov (United States)

    Liu, Hui; Liu, Hongxia; Sun, Ping; Wang, Zunyao

    2014-11-01

    The bioconcentration factors (BCFs) of 58 polychlorinated biphenyls (PCBs) were modeled by quantitative structure-activity relationship (QSAR) using density functional theory (DFT), the position of Cl substitution (PCS) and comparative molecular field analysis (CoMFA) methods. All the models were robust and predictive, and especially, the best CoMFA model was significant with a correlation coefficient (R(2)) of 0.926, a cross-validation correlation coefficient (Q(2)) of 0.821 and a root mean square error estimated (RMSE) of 0.235. The results indicate that the electrostatic descriptors play a more significant role in BCFs of PCBs. Additionally, a test set was used to compare the predictive ability of our models to others, and results show that our CoMFA model present the lowest RMSE. Thus, the models obtain in this work can be used to predict the BCFs of remaining 152 PCBs without available experimental values.

  17. Gas chromatography/atmospheric pressure chemical ionization/mass spectrometry for the analysis of organochlorine pesticides and polychlorinated biphenyls in human serum.

    Science.gov (United States)

    Geng, Dawei; Jogsten, Ingrid Ericson; Dunstan, Jody; Hagberg, Jessika; Wang, Thanh; Ruzzin, Jerome; Rabasa-Lhoret, Rémi; van Bavel, Bert

    2016-07-01

    A method using a novel atmospheric pressure chemical ionization source for coupling gas chromatography (GC/APCI) to triple quadrupole mass spectrometry (MS/MS) for the determination of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) regulated by the Stockholm Convention is presented. One microliter injection of a six-point calibration curve of native PCBs and OCPs, ranging from 0.04 to 300pg/μL, was performed. The relative standard deviation (RSD) of the relative response factors (RRFs) was less than 15% with a coefficient of determination (r(2))>0.995. Meanwhile, two calibration solutions (CS), CS 2 (0.4pg/μL) and CS 3 (4pg/μL) were analyzed to study the repeatability calculated for both area and RRFs. The RSD for RRF ranged from 3.1 to 16% and 3.6 to 5.5% for CS 2 and CS 3, respectively. The limits of detection (LOD) determined by peak-to-peak signal-to-noise ratio (S/N) of 3 were compared between the GC/APCI/MS/MS and a GC coupled to high resolution mass spectrometry (GC/HRMS) system. GC/APCI/MS/MS resulted in lower LOD for most of the compounds, except for PCB#74, cis-chlordane and trans-chlordane. GC/APCI/MS/MS and GC/HRMS were also compared by performing analysis on 75 human serum samples together with eight QA/QC serum samples. The comparison between GC/APCI/MS/MS system and GC/HRMS system for 16 of the targeted compounds was carried out. No statistically significant difference was discovered. Due to increased sensitivity and user friendly operation under atmospheric pressure, GC/APCI/MS/MS is a powerful alternative technique that can easily meet the specification of GC/HRMS.

  18. Selected organochlorine pesticides and polychlorinated biphenyls in atmosphere at Ruoergai high altitude prairie in eastern edge of Qinghai-Tibet Plateau and their source identifications

    Science.gov (United States)

    Gai, Nan; Pan, Jing; Tang, Hua; Tan, Ke-Yan; Chen, Da-Zhou; Zhu, Xiao-Hua; Lu, Guo-Hui; Chen, Shu; Huang, Yi; Yang, Yong-Liang

    2014-10-01

    Compared to the low-altitude areas, high-altitude regions have low air temperature and relatively high snow precipitation. These climatological characteristics will affect the environmental behavior of persistent organic pollutants (POPs) in such a special geographical environment, leading to cold-trapping of certain POPs in these areas. Ruoergai highland prairie in the eastern edge of the Qinghai-Tibetan Plateau was selected to study the distribution characteristics of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in aerosols and gas phase samples collected in two seasons of 2011 and measured by isotope dilution-HRGC/HRMS method. OCPs and PCBs in the Ruoergai air were at low levels compared with the adjacent populated areas such as Lanzhou and Chengdu. Higher concentrations of POPs in aerosol and gas phase were observed in winter than in summer, showing the impact of monsoon on the transport of POPs to this region. Northwesterly winds in winter may transport OCPs and PCBs from industrial and agricultural areas in the northwestern China. HCB, α-HCH, and PCB 28 were the predominant compounds found in the air. Soil to air fugacity ratios show that Ruoergai soils behave as a secondary source of the relatively volatile compounds (HCHs, α-endosulfan, PCB 28 and 52) to the atmosphere during summer and behave as a sink of atmospheric DDTs due to the OC-rich soils as well as lower temperatures. Similar 206Pb/207Pb and 208Pb/207Pb ratios in Ruoergai aerosols to those of aerosols of Lanzhou and ores in Qinghai, Xinjiang, Kazakhstan, and Russia may indicate that the aerosol sources were mainly related to air mass passing over the neighboring regions and countries.

  19. Bioaugmentation of a historically contaminated soil by polychlorinated biphenyls with Lentinus tigrinus

    Directory of Open Access Journals (Sweden)

    Federici Ermanno

    2012-03-01

    Full Text Available Abstract Background Several species belonging to the ecological group of white-rot basidiomycetes are able to bring about the remediation of matrices contaminated by a large variety of anthropic organic pollutants. Among them, polychlorobiphenyls (PCBs are characterized by a high recalcitrance due to both their low bioavailability and the inability of natural microbial communities to degrade them at significant rates and extents. Objective of this study was to assess the impact of a maize stalk-immobilized Lentinus tigrinus CBS 577.79 inoculant combined with soybean oil (SO, as a possible PCB-mobilizing agent, on the bioremediation and resident microbiota of an actual Aroclor 1260 historically contaminated soil under unsaturated solid-phase conditions. Results Best overall PCB depletions (33.6 ± 0.3% and dechlorination (23.2 ± 1.3% were found after 60 d incubation in the absence of SO where, however, the fungus appeared to exert adverse effects on both the growth of biphenyl- and chlorobenzoate-degrading bacteria and the abundance of genes coding for both biphenyl dioxygenase (bph and catechol-2,3-dioxygenase. A significant (P bph. Conclusions The PCB depletion extents obtained in the presence of L. tigrinus are by far higher than those reported in other remediation studies conducted under unsaturated solid phase conditions on actual site soils historically contaminated by Aroclor 1260. These results suggest that the bioaugmentation strategy with the maize stalk-immobilized mycelium of this species might be promising in the reclamation of PCB-contaminated soils. The addition of SO to matrices contaminated by technical PCB mixtures, such as Aroclor 1242 and Delor 103 and characterized by a large preponderance of low chlorinated congeners, might not be advisable.

  20. Assessment of polychlorinated biphenyls and organochlorine pesticides in water samples from the Yamuna River

    Directory of Open Access Journals (Sweden)

    Bhupander Kumar

    2012-07-01

    Full Text Available Polychlorinated biphenyls (PCBs, hexachlorocyclohexane (HCH and dichlorodiphenyltrichloroethane (DDT are toxic, persistent and bioaccumulative long-range atmospheric transport pollutants. These are transported worldwide affecting remote regions far from their original sources, and can transfer into food webs with a wide range of acute and chronic health effects. India ratified the Stockholm Convention with the intention of reducing and eliminating persistent organic pollutants (POPs, and encouraged the support of research on POPs. Despite the ban and restriction on the use of these chemicals in India, their contamination of air, water, sediment, biota and humans has been reported. In this study, surface water samples were collected during January 2012 from the Yamuna River in Delhi, India, and analyzed for PCBs and organochlorine pesticides (OCPs. The concentrations of ΣPCBs and ΣOCPs ranged between 2-779 ng L–1 and from less than 0.1 to 618 ng L–1 (mean 99±38 ng L–1 and 221±50 ng L–1, respectively. The PCB homolog was dominated by 3-4 chlorinated biphenyls. In calculating the toxicity equivalent of dioxin-like PCBs (dl-PCBsusing World Health Organization toxic equivalency factors, dl-PCBs accounted for 10% of a total of 27 PCBs. The concentration of ΣHCH ranged between less than 0.1 and 285 ng L–1 (mean 151±32 ng L–1. However, ΣDDTs concentrations varied between less than 0.1 and 354 ng L–1 (mean 83±26 ng L–1. The concentrations were lower than the US guideline values; however, levels of lindane exceeded those recommended in guidelines. Further in-depth study is proposed to determine the bioaccumulation of these pollutants through aquatic biota to assess the risk of contaminants to human health.

  1. Microwave-assisted steam distillation for simple determination of polychlorinated biphenyls and organochlorine pesticides in sediments.

    Science.gov (United States)

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

    2003-03-15

    A novel sample extraction technique for polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) analysis using microwave-heating device is developed. In this study, microwave-assisted extraction (MAE) and steam distillation techniques were combined. Desorption of the anatytes from solid matrixes was accelerated with water vapor which was generated by microwave irradiation. A sample holder in a commercial microwave extraction cell kept the sample from direct contact with the organic solvent for analytes trapping during the treatment process. Therefore, relatively clean extracts were obtained with small amount of solvents. Without any cleanup steps, the obtained extract could be analyzed with gas chromatograph/mass spectrometers (GC/MS). Six PCB congeners (PCB15, 28, 70, 101, 180, 194, 209) and three OCPs (gamma-HCH, 4,4'-DDE, 4,4'-DDD) in two marine sediment samples (a sediment collected from a bay of Kyusyu Island, Japan, and a certified reference material NIST SRM1944) were analyzed by using this microwave-assisted steam distillation (MASD) technique and another extraction method (exhaustive steam distillation, MAE, and Soxhlet extraction); and comparisons of the results are shown in this report. Although recovery yields of highly chlorinated biphenyls (PCB180, 194, 209) and relatively polar OCPs (gamma-HCH, 4,4'-DDD) were low (30-60%) compared with other analytes (PCB15, 28, 70, 101, 4,4'-DDE; recovery, 80-100%), use of isotope labeled internal standards for the MASD technique gave comparable results with the values obtained by other extraction methods and the certified values in the samples.

  2. Volatile Organic Compounds (VOCs)

    Science.gov (United States)

    ... Share Facebook Twitter Google+ Pinterest Contact Us Volatile Organic Compounds' Impact on Indoor Air Quality On this ... Exposure Standards or Guidelines Additional Resources Introduction Volatile organic compounds (VOCs) are emitted as gases from certain ...

  3. Reissert compound of bisbenzimidazole

    OpenAIRE

    1989-01-01

    A Reissert compound of bisbenzimidazole can be formed by first reacting benzimidazole with an aliphatic diacid chloride to form bisbenzimidazole and then reacting the bisbenzimidazole with an aliphatic acid chloride and cyanide to form the Reissert compound thereof.

  4. Nondestructive pollution exposure assessment in the European hedgehog (Erinaceus europaeus): III. Hair as an indicator of endogenous organochlorine compound concentrations.

    Science.gov (United States)

    D'Havé, Helga; Scheirs, Jan; Covaci, Adrian; Schepens, Paul; Verhagen, Ron; De Coen, Wim

    2006-01-01

    Concentrations of organochlorine persistent pollutants were investigated in tissues of the European hedgehog (Erinaceus europaeus). Road kills and carcasses from wildlife rescue centers were used to characterize organochlorine compound tissue distribution and tissue profile dissimilarities (hair, liver, kidney, muscle, and adipose tissue). The most important contaminants were polychlorinated biphenyls (PCBs), chlordanes (CHLs), and DDTs, with median concentrations of 75, 5.1, and 1.4 ng/g liver wet weight, respectively. Median levels for the remaining compounds-hexachlorobenzene (HCB), hexachlorocyclohexanes (HCHs), and octachlorostyrene-were less than 0.5 ng/g liver wet weight. Compared to results with other mammalian wildlife, the present results indicate that hedgehogs may accumulate considerable concentrations of organochlorine compounds. Polychlorinated biphenyls and HCB preferably accumulated in liver and muscle tissue. Concentrations of DDTs and HCHs were highest in muscle tissue and hair, respectively. Octachlorostyrene and CHL levels were predominant in liver. The observed positive relationships between concentrations in hair and internal tissues for PCBs, DDTs, HCB, HCHs, and CHLs (0.49 hedgehog hair as a nondestructive biomonitoring tool regarding pollution with organochlorine compounds and the promising role of the hedgehog as a mammalian indicator species of pollution in terrestrial environments.

  5. Comparison of organochlorine compound concentrations in colostrum and mature milk.

    Science.gov (United States)

    Yu, Zhiwei; Palkovicova, Lubica; Drobna, Beata; Petrik, Jan; Kocan, Anton; Trnovec, Tomas; Hertz-Picciotto, Irva

    2007-01-01

    Human breast milk represents the best choice for the nutrition of infants. It is often used for monitoring human exposures to environmental chemicals. Uniquely suited to meet human biological needs, breast milk composition, especially fat content, changes significantly with time from delivery. With the aim to compare the concentration of organochlorine compounds (OCs) in colostrum versus mature milk, we obtained samples of fourth-fifth day postpartum milk (colostrum) and day-14 postpartum milk (mature milk) from 12 women enrolled in the project "Early Childhood Development and PCB Exposure in Slovakia". The concentrations of selected organochlorine pesticides and congeners of polychlorinated biphenyls (PCBs) were measured using gas chromatography with electron capture detection and reported on lipid adjusted basis. No significant differences were found between organochlorine levels in colostrum and those in mature milk samples. A very close correlation was found between the concentrations of organochlorine compounds in colostrum and mature milk (Spearman correlation coefficient r=0.94-0.98 for PCBs, and r=0.85-0.99 for organochlorine pesticides, p<0.001 for all compounds). The present study concludes that the use of colostrum samples provides a close estimate of the child's exposure to OCs in the early neonatal period and demonstrates that, despite the lower fat content, colostrum specimens are adequate to conduct OC analyses.

  6. A cohort study of the association between secondary sex ratio and parental exposure to polybrominated biphenyl (PBB and polychlorinated biphenyl (PCB

    Directory of Open Access Journals (Sweden)

    Terrell Metrecia L

    2009-08-01

    Full Text Available Abstract Background Polybrominated biphenyl (PBB, a brominated flame retardant, was accidently mixed into animal feed in Michigan (1973–1974 resulting in human exposure through consumption of contaminated meat, milk and eggs. Beginning in 1976 individuals who consumed contaminated products were enrolled in the Michigan Long-Term PBB Study. This cohort presents a unique opportunity to study the association between parental exposures to PBB and offspring sex ratio. Methods We identified offspring of female PBB cohort participants (born 1975–1988 and obtained electronic birth records for those born in the state of Michigan. We linked this information to parental serum PBB and PCB concentrations collected at enrollment into the cohort. We modeled the odds of a male birth with generalized estimating equations accounting for the non-independence of siblings born to the same parents. We explored potential confounders: parental age and education at offspring's birth, parental body mass index at cohort enrollment, birth order, gestational age and year of offspring's birth. Results The overall proportion of male offspring among 865 live births to cohort mothers was 0.542. This was higher than the national male proportion of 0.514 (binomial test: p = 0.10. When both parents were in the cohort (n = 300, we found increased odds of a male birth with combined parents' enrollment PBB exposure ≥ the median concentrations (3 μg/L for mothers; 6 μg/L for fathers compared to combined parents' PBB exposure Conclusion This study adds to the body of literature on secondary sex ratio and exposure to environmental contaminants. In this population, combined parental exposure to PBBs or PCBs increased the odds of a male birth. Further research is needed to corroborate these findings and shed light on the biological mechanisms by which these types of chemicals may influence the secondary sex ratio.

  7. Polychlorinated biphenyls and hydroxylated polychlorinated biphenyls in plasma of bottlenose dolphins (Tursiops truncatus) from the Western Atlantic and the Gulf of Mexico.

    Science.gov (United States)

    Houde, Magali; Pacepavicius, Grazina; Wells, Randall S; Fair, Patricia A; Letcher, Robert J; Alaee, Mehran; Bossart, Gregory D; Hohn, Aleta A; Sweeney, Jay; Solomon, Keith R; Muir, Derek C G

    2006-10-01

    Polychlorinated biphenyls (PCBs) and hydroxylated metabolic products (OH-PCBs) were measured in plasma collected from live-captured and released bottlenose dolphins (Tursiops truncatus) from five different locations in the Western Atlantic and the Gulf of Mexico in 2003 and 2004. In 2004, the sum (sigma) of concentration of PCBs in plasma of dolphins sampled off Charleston, SC [geometric mean: 223 ng/g of wet weight (w.w.)] was significantly higher (pRiver Lagoon, FL (sigmaPCBs: 122 ng/g w.w.) and the Sarasota Bay, FL (sigmaPCBs: 111 ng/g w.w.). The PCB homolog profiles were similar among locations. Concentrations of OH-PCBs were significantly higher (p<0.05) in plasma of dolphins from Charleston, SC (sigmaOH-PCBs for 2003: 126 ng/g w.w.; 2004: 138 ng/g w.w.) than animals from Florida (sigmaOH-PCBs ranged from 6 to 47 ng/g w.w.) and Bermuda (8.3 ng/g w.w.); however, concentrations in the Charleston samples did not differ from animals captured in Delaware Bay, NJ (57 ng/g w.w.). The sigmaOH-PCBs constituted 2-68% of the total PCB concentrations in plasma. Dichloro- to nonachloro-OH-PCBs were quantified using high-resolution gas chromatography mass spectrometry, but only around 20% of OH-PCBs could be identified by comparison to authentic standards. Results from this study show that OH-PCB are important environmental contaminants in dolphins and suggest that PCBs, decades after their ban, may still constitute a threat to wildlife.

  8. Synthesis, molecular structure, spectroscopic investigations and computational study of a potential molecular switch of 2-([1,1'-biphenyl]-4-yl)-2-methyl-6-(4-nitrophenyl)-4-phenyl-1,3 diazabicyclo [3.1.0]hex-3-ene

    Indian Academy of Sciences (India)

    AYOUB KANAANI; DAVOOD AJLOO; HAMZEH I KIYAN; FRESHTE SHAHERI; MAJID AMIRI

    2016-08-01

    This work presents a combined experimental and theoretical study on a photochromic compound, 2-([1,1'-biphenyl]-4-yl)-2-methyl-6-(4-nitrophenyl)-4-phenyl-1,3 diazabicyclo [3.1.0]hex-3-ene, existing in closed form (‘A’) and open form (‘B’). The spectroscopic properties of the title compound have beeninvestigated by using IR, UV–Vis and ¹H NMR techniques. The molecular geometry and spectroscopic data of the title compound have been calculated by using the density functional method (B3LYP) invoking 6-311G(d,p) basis set. UV-Vis spectra of the two forms were recorded. The excitation energies, oscillator strength, etc., were calculated by time-dependent density functional theory (TD-DFT). Furthermore, molecular electrostatic potential map (MEP), frontier molecular orbital analysis (HOMO–LUMO), total density of state (TDOS) and reactivity descriptors were found and discussed. We applied a first-principles computational approach to study a light-sensitive molecular switch. We find that the conductance of the two isomers varies dramatically, which suggests that this system has potential use as a molecular switch.

  9. Endogenous hydrogen peroxide is a key factor in the yeast extract-induced activation of biphenyl biosynthesis in cell cultures of Sorbus aucuparia.

    Science.gov (United States)

    Qiu, Xiaofang; Lei, Caiyan; Huang, Lili; Li, Xing; Hao, He; Du, Zhigao; Wang, Hong; Ye, Hechun; Beerhues, Ludger; Liu, Benye

    2012-01-01

    Biphenyls are unique phytoalexins produced by plants belonging to Pyrinae, a subtribe of the economically important Rosaceae family. The formation of aucuparin, a well-known biphenyl, is induced by yeast extract (YE) in cell cultures of Sorbus aucuparia. However, the molecular mechanism underlying YE-induced activation of biphenyl biosynthesis remains unknown. Here we demonstrate that the addition of YE to the cell cultures results in a burst of reactive oxygen species (ROS; H(2)O(2) and O(2) (-)), followed by transcriptional activation of the biphenyl synthase 1 gene (BIS1) encoding the key enzyme of the biphenyl biosynthetic pathway and aucuparin accumulation. Pretreatment of the cell cultures with ROS scavenger dihydrolipoic acid and NADPH oxidase-specific inhibitor diphenylene iodonium abolished all of the above YE-induced biological events. However, when the cell cultures was pretreated with superoxide dismutase specific inhibitor N,N-diethyldithiocarbamic acid, although O(2) (-) continued to be generated, the H(2)O(2) accumulation, BIS1 expression and aucuparin production were blocked. Interestingly, exogenous supply of H(2)O(2) in the range of 0.05-10 mM failed to induce aucuparin accumulation. These results indicate that endogenous generation of H(2)O(2) rather than that of O(2) (-) is a key factor in YE-induced accumulation of biphenyl phytoalexins in cell cultures of S. aucuparia.

  10. Enhanced reductive dechlorination of polychlorinated biphenyl-contaminated soil by in-vessel anaerobic composting with zero-valent iron.

    Science.gov (United States)

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

    2014-03-01

    Anaerobic dechlorination is an effective degradation pathway for higher chlorinated polychlorinated biphenyls (PCBs). The enhanced reductive dechlorination of PCB-contaminated soil by anaerobic composting with zero-valent iron (ZVI) was studied, and preliminary reasons for the enhanced reductive dechlorination with ZVI were investigated. The results show that the addition of nanoscale ZVI can enhance dechlorination during in-vessel anaerobic composting. After 140 days, the average number of removed Cl per biphenyl with 10 mg g(-1) of added nanoscale ZVI was 0.63, enhancing the dechlorination by 34 % and improving the initial dechlorination speed. The ZVI enhances dechlorination by providing a suitable acid base environment, reducing volatile fatty acid inhibition and stimulating the microorganisms. The C/N ratios for treatments with the highest rate of ZVI addition were smaller than for the control, indicating that ZVI addition can promote compost maturity.

  11. The Effect of Dietary Glycine on the Hepatic Tumor Promoting Activity of Polychlorinated Biphenyls (PCBs) in Rats

    OpenAIRE

    Bunaciu, Rodica Petruta; Tharappel, Job C.; Lehmler, Hans-Joachim; Korwel, Izabela; Robertson, Larry W.; Srinivasan, Cidambi; Spear, Brett T.; Glauert, Howard P.

    2007-01-01

    Polychlorinated biphenyls (PCBs) are ubiquitious lipophilic environmental pollutants. Some of the PCB congeners and mixtures of congeners have tumor promoting activity in rat liver. The mechanism of their activity is not fully understood and is likely to be multifactorial. The aim of this study was to investigate if the resident liver macrophages, Kupffer cells, are important in the promoting activity of PCBs. The hypothesis of this study was that the inhibition of Kupffer cell activity would...

  12. Activity of alkaline and acidic phosphatase in glandular cells of uterine endometrium of puerperal ewes after exposure to polychlorinated biphenyls

    OpenAIRE

    Valocky I.; Krajničakova Maria; Legath J.; Lenhardt L.; Ostro A.; Danko J.; Tkačikova L`udmila; Mojžišova Jana; Fialkovičova Maria; Mardzinova Silvia

    2005-01-01

    The study is focused on the observation of alkaline and acidic phosphatase activity in the glandular cells of uterine endometrium in puerperal ewes after exposure to polychlorinated biphenyls. Ewes of Slovak merino breed (n=25) divided into 2 groups were included in the experiment. The animals in the experimental group (n=14) and control group (n=11) were euthanised on day 17, 25 and 34 postpartum. The ewes in the experimental group were given per os capsules of the chemical preparation Delor...

  13. Polychlorinated Biphenyls Disturb Differentiation of Normal Human Neural Progenitor Cells: Clue for Involvement of Thyroid Hormone Receptors

    OpenAIRE

    Fritsche, Ellen; Cline, Jason E.; Nguyen, Ngoc-Ha; Scanlan, Thomas S.; Abel, Josef

    2005-01-01

    Polychlorinated biphenyls (PCBs) are ubiquitous environmental chemicals that accumulate in adipose tissues over the food chain. Epidemiologic studies have indicated that PCBs influence brain development. Children who are exposed to PCBs during development suffer from neuropsychologic deficits such as a lower full-scale IQ (intelligence quotient), reduced visual recognition memory, and attention and motor deficits. The mechanisms leading to these effects are not fully understood. It has been s...

  14. Rapid Detection of Polychlorinated Biphenyls at Trace Levels in Real Environmental Samples by Surface-Enhanced Raman Scattering

    Directory of Open Access Journals (Sweden)

    Zhengjun Zhang

    2011-11-01

    Full Text Available 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.

  15. Magnetoelectrochemistry of 4,4'-bis(dimethylamino)biphenyl and 4,4'-dinitrobiphenyl azacrown macrocyclic lactams

    Energy Technology Data Exchange (ETDEWEB)

    Domenech, Antonio [Departament de Quimica Analitica, Universitat de Valencia, Dr. Moliner 50, 46100 Burjassot, Valencia (Spain); Costero, Ana Maria; Banuls, Maria Jose; Aurell, Maria Jose [Departament de Quimica Organica, Universitat de Valencia, Dr. Moliner 50, 46100 Burjassot, Valencia (Spain)

    2005-07-25

    The voltammetric behaviour at carbon fibre microelectrodes under the application of static magnetic fields of two series of macrolactams containing in their structure 4,4'-bis(dimethylamino)biphenyl or 4,4'-dinitrobiphenyl groups in MeCN solution is described. The response of 4,4'-dinitrobiphenyl receptors is dominated by two successive one-electron reduction processes at -0.9 and -1.6 V versus AgCl/Ag. 4,4'-bis(dimethylamino)biphenyl-containing receptors display two one-electron oxidations above +0.8 and +1.0 V. In both cases, a dihedral/planar interconversion precedes the second electron transfer step. Upon application of moderate (0.05-0.2 T) static magnetic fields to the electrochemical cell, the rate of such dihedral/planar interconversion is lowered for both the reduction of 4,4'-dinitrobiphenyl receptors and the oxidation of 4,4'-bis(dimethylamino)biphenyl lactams. The electrochemical response of N-methylated receptors, for which different cisoid-cisoid, cisoid-transoid, and transoid-transoid forms exist, exhibits a significant peak splitting that can be associated to the presence of such conformational isomers. Application of magnetic fields produces a relative enhancement of some peaks that can be interpreted in terms of differential magnetoconvection involving such conformational isomers. (author)

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

    Science.gov (United States)

    Mora, Miguel A.

    1996-01-01

    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 Laguna Madre were below concentrations known to affect bird reproduction.

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

    Energy Technology Data Exchange (ETDEWEB)

    Mora, M.A. [Texas A and M Univ., College Station, TX (United States)

    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.

  18. Ecotoxicology of organofluorous compounds.

    Science.gov (United States)

    Murphy, Margaret B; Loi, Eva I H; Kwok, Karen Y; Lam, Paul K S

    2012-01-01

    Organofluorous compounds have been developed for myriad purposes in a variety of fields, including manufacturing, industry, agriculture, and medicine. The widespread use and application of these compounds has led to increasing concern about their potential ecological toxicity, particularly because of the stability of the C-F bond, which can result in chemical persistence in the environment. This chapter reviews the chemical properties and ecotoxicology of four groups of organofluorous compounds: fluorinated refrigerants and propellants, per- and polyfluorinated compounds (PFCs), fluorinated pesticides, and fluoroquinolone antibiotics. These groups vary in their environmental fate and partitioning, but each raises concern in terms of ecological risk on both the regional and global scale, particularly those compounds with long environmental half-lives. Further research on the occurrence and toxicities of many of these compounds is needed for a more comprehensive understanding of their ecological effects.

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

    Directory of Open Access Journals (Sweden)

    Di Toro Sara

    2009-01-01

    Full Text Available Abstract 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

  20. Hazardous organic compounds in biogas plant end products--soil burden and risk to food safety.

    Science.gov (United States)

    Suominen, K; Verta, M; Marttinen, S

    2014-09-01

    The end products (digestate, solid fraction of the digestate, liquid fraction of the digestate) of ten biogas production lines in Finland were analyzed for ten hazardous organic compounds or compound groups: polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), polychlorinated biphenyls (PCB(7)), polyaromatic hydrocarbons (PAH(16)), bis-(2-ethylhexyl) phthalate (DEHP), perfluorinated alkyl compounds (PFCs), linear alkylbenzene sulfonates (LASs), nonylphenols and nonylphenol ethoxylates (NP+NPEOs), polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD) and tetrabromobisphenol A (TBBPA). Biogas plant feedstocks were divided into six groups: municipal sewage sludge, municipal biowaste, fat, food industry by-products, animal manure and others (consisting of milling by-products (husk) and raw former foodstuffs of animal origin from the retail trade). There was no clear connection between the origin of the feedstocks of a plant and the concentrations of hazardous organic compounds in the digestate. For PCDD/Fs and for DEHP, the median soil burden of the compound after a single addition of digestate was similar to the annual atmospheric deposition of the compound or compound group in Finland or other Nordic countries. For PFCs, the median soil burden was somewhat lower than the atmospheric deposition in Finland or Sweden. For NP+NPEOs, the soil burden was somewhat higher than the atmospheric deposition in Denmark. The median soil burden of PBDEs was 400 to 1000 times higher than the PBDE air deposition in Finland or in Sweden. With PBDEs, PFCs and HBCD, the impact of the use of end products should be a focus of further research. Highly persistent compounds, such as PBDE- and PFC-compounds may accumulate in agricultural soil after repeated use of organic fertilizers containing these compounds. For other compounds included in this study, agricultural use of biogas plant end products is unlikely to cause risk to food safety in Finland.

  1. Organic compounds in produced waters from coalbed natural gas wells in the Powder River Basin, Wyoming, USA

    Science.gov (United States)

    Orem, W.H.; Tatu, C.A.; Lerch, H.E.; Rice, C.A.; Bartos, T.T.; Bates, A.L.; Tewalt, S.; Corum, M.D.

    2007-01-01

    The organic composition of produced water samples from coalbed natural gas (CBNG) wells in the Powder River Basin, WY, sampled in 2001 and 2002 are reported as part of a larger study of the potential health and environmental effects of organic compounds derived from coal. The quality of CBNG produced waters is a potential environmental concern and disposal problem for CBNG producers, and no previous studies of organic compounds in CBNG produced water have been published. Organic compounds identified in the produced water samples included: phenols, biphenyls, N-, O-, and S-containing heterocyclic compounds, polycyclic aromatic hydrocarbons (PAHs), aromatic amines, various non-aromatic compounds, and phthalates. Many of the identified organic compounds (phenols, heterocyclic compounds, PAHs) are probably coal-derived. PAHs represented the group of organic compounds most commonly observed. Concentrations of total PAHs ranged up to 23 ??g/L. Concentrations of individual compounds ranged from about 18 to compound concentrations was documented, as two wells with relatively high organic compound contents in produced water in 2001 had much lower concentrations in 2002. In many areas, including the PRB, coal strata provide aquifers for drinking water wells. Organic compounds observed in produced water are also likely present in drinking water supplied from wells in the coal. Some of the organic compounds identified in the produced water samples are potentially toxic, but at the levels measured in these samples are unlikely to have acute health effects. The human health effects of low-level, chronic exposure to coal-derived organic compounds in drinking water are currently unknown. Continuing studies will evaluate possible toxic effects from low level, chronic exposure to coal-derived organic compounds in drinking water supplies.

  2. [GC x GC measurements of atmospheric aromatic compounds near a busy high-speed road in Beijing].

    Science.gov (United States)

    Mao, Ting; Xu, Xiao-bin; Wang, Ying

    2009-10-15

    Comprehensive two-dimensional gas chromatography (GC x GC) is a powerful instrumental tool often used to analyze complex mixtures. An optimized GC x GC method had been applied to the quantitative analysis of aromatic compounds in air samples collected near a busy high-speed road in Beijing during the 2007 National Holidays. In the resulting GC x GC chromatograms, aromatic species were resolved from other compound classes and were grouped in a manner that facilitated identification and integration, showing more information of aromatic compounds compared to traditional one-dimensional GC. Totally more than 30 aromatic species were identified and quantified. The average concentrations of monocyclic aromatic compounds ranged from 0.75 x 10(-9) to 24.64 x 10(-9) C, with toluene having the highest concentration, followed by m, p-xylene and ethylbenzene. The average concentrations of the measured polycyclic aromatic compounds ranged from 0.03 x 10(-9) to 2.28 x 10(-9) C, with naphthalene having the highest concentration, followed by 2-methyl-naphthalene and 4-methyl-1, 1'-biphenyl. The four-ring and higher polycyclic aromatic compounds were not detectable in the gaseous samples. The levels of aromatic compounds were significantly influenced by meteorological parameters. Benzene and toluene were poorly correlated with higher aromatic compounds though the latter compounds were highly correlated among each other, suggesting that both were significantly influenced by sources other than vehicle exhaust and gasoline evaporation.

  3. Insight into the structural requirement of substituted quinazolinone biphenyl acylsulfonamides derivatives as Angiotensin II AT1 receptor antagonist: 2D and 3D QSAR approach

    Directory of Open Access Journals (Sweden)

    Mukesh C. Sharma

    2014-01-01

    Full Text Available A series of 19 molecules substituted quinazolinone biphenyl acylsulfonamides derivatives displaying variable inhibition of Angiotensin II receptor AT1 activity were selected to develop models for establishing 2D and 3D QSAR. The compounds in the selected series were characterized by spatial, molecular and electro topological descriptors using QSAR module of Molecular Design Suite (VLife MDS™ 3.5. The best 2D QSAR model was selected, having correlation coefficient r2 (0.8056 and cross validated squared correlation coefficient q2 (0.6742 with external predictive ability of pred_r2 0.7583 coefficient of correlation of predicted data set (pred_r2se 0.2165. The results obtained from QSAR studies could be used in designing better Ang II activity among the congeners in future. The optimum QSAR model showed that the parameters SsssCHE index, SddCE-index, T_2_Cl_4, and SssNHE-index contributed in the model. 3D QSAR analysis by kNN-molecular field analysis approach developed based on principles of the k-nearest neighbor method combined with Genetic algorithms, stepwise forward variable selection approach; a leave-one-out cross-validated correlation coefficient (q2 of 0.6516 and a non-cross-validated correlation coefficient (r2 of 0.8316 and pred_r2 0.6954 were obtained. Contour maps using this approach showed that steric, electrostatic, and hydrophobic field effects dominantly determine binding affinities. The information rendered by 3D QSAR models may lead to a better understanding of structural requirements of Angiotensin II receptor and can help in the design of novel potent antihypertensive molecules.

  4. Analyses of polychlorinated biphenyls in waters and wastewaters using vortex-assisted liquid-liquid microextraction and gas chromatography-mass spectrometry.

    Science.gov (United States)

    Ozcan, Senar

    2011-03-01

    A method was developed for viable and rapid determination of seven polychlorinated biphenyls (PCBs) in water samples with vortex-assisted liquid-liquid microextraction (VALLME) using gas chromatography-mass spectrometry (GC-MS). At first, the most suitable extraction solvent and extraction solvent volume were determined. Later, the parameters affecting the extraction efficiency such as vortex extraction time, rotational speed of the vortex, and ionic strength of the sample were optimized by using a 2(3) factorial experimental design. The optimized extraction conditions for 5 mL water sample were as follows: extractant solvent 200 μL of chloroform; vortex extraction time of 2 min at 3000 rpm; centrifugation 5 min at 4000 rpm, and no ionic strength. Under the optimum condition, limits of detection (LOD) ranged from 0.36 to 0.73 ng/L. Mean recoveries of PCBs from fortified water samples are 96% for three different fortification levels and RSDs of the recoveries are below 5%. The developed procedure was successfully applied to the determination of PCBs in real water and wastewater samples such as tap, well, surface, bottled waters, and municipal, treated municipal, and industrial wastewaters. The performance of the proposed method was compared with traditional liquid-liquid extraction (LLE) of real water samples and the results show that efficiency of proposed method is comparable to the LLE. However, the proposed method offers several advantages, i.e. reducing sample requirement for measurement of target compounds, less solvent consumption, and reducing the costs associated with solvent purchase and waste disposal. It is also viable, rapid, and easy to use for the analyses of PCBs in water samples by using GC-MS.

  5. In vitro toxicity profiling of ultrapure non-dioxin-like polychlorinated biphenyl congeners and their relative toxic contribution to PCB mixtures in humans.

    Science.gov (United States)

    Hamers, Timo; Kamstra, Jorke H; Cenijn, Peter H; Pencikova, Katerina; Palkova, Lenka; Simeckova, Pavlina; Vondracek, Jan; Andersson, Patrik L; Stenberg, Mia; Machala, Miroslav

    2011-05-01

    The toxic equivalency concept used for the risk assessment of polychlorinated biphenyls (PCBs) is based on the aryl hydrocarbon receptor (AhR)-mediated toxicity of coplanar dioxin-like (DL) PCBs. Most PCBs in the environment, however, are non-dioxin-like (NDL) PCBs that cannot adopt a coplanar structure required for AhR activation. For NDL-PCBs, no generally accepted risk concept is available because their toxicity is insufficiently characterized. Here, we systematically determined in vitro toxicity profiles for 24 PCBs regarding 10 different mechanisms of action. Prior to testing, NDL-PCB standards were purified to remove traces of DL compounds. All NDL-PCBs antagonized androgen receptor activation and inhibited gap junctional intercellular communication (GJIC). Lower chlorinated NDL-PCBs were weak estrogen receptor (ER) agonists, whereas higher chlorinated NDL-PCBs were weak ER antagonists. Several NDL-PCBs inhibited estradiol-sulfotransferase activity and bound to transthyretin (TTR) but with much weaker potencies than reported for hydroxylated PCB metabolites. AhR-mediated expression of uridine-glucuronyl transferase isozyme UGT1A6 was induced by DL-PCBs only. Hierarchical cluster analysis of the toxicity profiles yielded three separate clusters of NDL-PCBs and a fourth cluster of reference DL-PCBs. Due to small differences in relative potency among congeners, the highly abundant indicator PCBs 28, 52, 101, 118, 138, 153, and 180 also contributed most to the antiandrogenic, (anti)estrogenic, antithyroidal, tumor-promoting, and neurotoxic potencies calculated for PCB mixtures reported in human samples, whereas the most potent AhR-activating DL-PCB-126 contributed at maximum 0.2% to any of these calculated potencies. PCB-168 is recommended as an additional indicator congener, given its relatively high abundance and antiandrogenic, TTR-binding, and GJIC-inhibiting potencies.

  6. Association between dietary intake of polychlorinated biphenyls and the incidence of hypertension in a Spanish cohort: the Seguimiento Universidad de Navarra project.

    Science.gov (United States)

    Donat-Vargas, Carolina; Gea, Alfredo; Sayon-Orea, Carmen; de la Fuente-Arrillaga, Carmen; Martinez-Gonzalez, Miguel Angel; Bes-Rastrollo, Maira

    2015-04-01

    Polychlorinated biphenyls are persistent organic pollutants that are consumed because of their bioaccumulation through the food chain. Evidence from different sources suggests a positive association between polychlorinated biphenyls exposure and the incidence of hypertension. However, no previous prospective study has investigated this potential relationship in adults. We prospectively assessed the association between dietary intake of polychlorinated biphenyls and the incidence of hypertension in a large cohort. The Seguimiento Universidad de Navarra project is a Spanish cohort of university graduates, most of them health professionals. We included 14521 participants, initially free of hypertension, who were followed-up for a median of 8.3 years. Dietary intake of polychlorinated biphenyls was assessed at baseline through a previously validated 136-item semiquantitative food frequency questionnaire. The published concentration levels of polychlorinated biphenyls measured in samples of food consumed in Spain were used to estimate dietary intake. Multivariable Cox regression models were fitted to estimate hazard ratios and 95% confidence interval for incident hypertension. During follow-up, 1497 incident cases of medically diagnosed hypertension were identified. After adjusting for total energy intake and for potential confounders, participants in the fifth quintile of total polychlorinated biphenyls intake were at higher risk of developing hypertension (adjusted hazard ratio, 1.43 [95% confidence interval, 1.09-1.88; P for trend 0.017]) compared with those in the first quintile. In this Mediterranean cohort, dietary intake of polychlorinated biphenyls, estimated using a food frequency questionnaire, was associated with a higher risk of developing hypertension during follow-up. Nevertheless, further longitudinal studies are needed to confirm our results.

  7. Polychlorinated biphenyl (PCB) and dioxin concentrations in residential dust of pregnant women.

    Science.gov (United States)

    Hinwood, A L; Callan, A C; Heyworth, J; Rogic, D; de Araujo, J; Crough, R; Mamahit, G; Piro, N; Yates, A; Stevenson, G; Odland, J Ø

    2014-12-01

    Polychlorinated biphenyls (PCBs) and dioxins are well known for their persistence in the environment. PCBs can be found in the residential environment long after the use of these chemicals in domestic products and industrial processes has ceased. Dioxins have been assessed in Australia as being of very low concentrations. Despite concerns about residential dust as a source of human exposure to persistent chemicals, there has been limited testing of PCBs and dioxins in dust in Australia. As part of an assessment of maternal exposure to a variety of persistent toxic substances, we analysed 30 residential dust samples from a variety of geographical settings for their dioxin and PCB concentrations. PCBs were found in most samples, the median and range concentrations (pg g(-1)) of dominant congeners of PCB were as follows: PCB118 (315; PCB105 (130; 14.0-16 000) and PCB156 (440; PCB congener concentrations and dioxin isomers in multivariate regression analyses. No other housing or sociodemographic variables, including proximity to industry, were important predictors in multivariate linear regression models.

  8. Geminate recombination kinetics of solute radical ions. Singlet excited state formation in cyclohexane solutions of biphenyl

    Science.gov (United States)

    Tagawa, S.; Washio, M.; Tabata, Y.; Kobayashi, H.

    Transient absorption spectra of the solute anion, cation and triplet state and the solute fluorescence in the pulse radiolysis of 0.1 mole 1 -1 biphenyl in cyclohexane were observed on a nanosecond timescale longer than 1 ns after a 20 ps pulse. The formation of the solute excited singlet state is mainly due to the geminate ion recombination reaction even in the high concentrated solutions. The decay of the solute ions obeys the reciprocal square root dependence on time longer than 10 ns from the end of a 10 ps pulse. The slope of this reciprocal square root plots agrees with the literature value on a longer timescale obtained by microwave absorption. The yield of free ions obtained from the intercept of the slope agrees also with the literature values obtained by the field clearing method. Ratio of the formation rate of the solute excited triplet state to the decay rate of the solute anion changes in a time range between 5 and 20 ns. It is very well correlated with a theoretical calculation of spin correlation decay of the germinate ion pairs by Brocklehurst, although the formation of the solute triplet state was observed even on a timescale shorter than 5 ns from the end of a 20 ps pulse, where loss of spin correlation is negligibly small.

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

    Science.gov (United States)

    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 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.

  10. Modeling the depuration rates of polychlorinated biphenyls in two mussel species with theoretical molecular descriptors

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Using theoretical molecular descriptors as well as partial least squares(PLS) regression,two quantitative structure-activity relationship(QSAR) models were developed for depuration rate constants(kd) of polychlorinated biphenyls(PCBs) in two species of mussels,Perna viridis and Dreissena polymorpha.The cross-validated Q2cum(an indicator of fitting of goodness) values for the two models are 0.501 and 0.756,and the standard deviation(SD) is 0.084 and 0.076,respectively.The achievement of satisfactory Q2cum and low SD values indicates good predictive ability and precision of the two models.The significant descriptors governing lgkd include polarizability(α),molecular volume(MV),molecular weight(Mw),molecular surface area(S),and total energy(TE).The key descriptors in the models reflect that van der Waals interactions play a dominant role in the depuration of PCBs.The depuration of PCBs in the two mussel species may be mainly attributed to the biota-water phase partitioning processes.

  11. A Chloroflexi bacterium dechlorinates polychlorinated biphenyls in marine sediments under in situ-like biogeochemical conditions.

    Science.gov (United States)

    Zanaroli, Giulio; Balloi, Annalisa; Negroni, Andrea; Borruso, Luigimaria; Daffonchio, Daniele; Fava, Fabio

    2012-03-30

    We investigated the reductive dechlorination of Aroclor 1254 PCBs by a coplanar PCB-dechlorinating microbial community enriched from an actual site contaminated marine sediment of the Venice lagoon in sterile slurry microcosms of the same sediment suspended in its site water, i.e., under biogeochemical conditions that closely mime those occurring in situ. The culture dechlorinated more than 75% of the penta- through hepta-chlorinated biphenyls to tri- and tetra-chlorinated congeners in 30 weeks. The dechlorination rate was reduced by the addition of H(2) and short chain fatty acids, which stimulated sulfate-reduction and methane production, and markedly increased by the presence of vancomycin or ampicillin. DGGE analysis of 16S rRNA genes on PCB-spiked and PCB-free cultures ruled out sulfate-reducing and methanogenic bacteria and revealed the presence of a single Chloroflexi phylotype closely related to the uncultured bacteria m-1 and SF1 associated to PCB dechlorination. These findings suggest that a single dechlorinator is responsible for the observed extensive dechlorination of Aroclor 1254 and that a Chloroflexi species similar to those already detected in freshwater and estuarine contaminated sediments mediates PCB dechlorination in the marine sediment adopted in this study under biogeochemical conditions resembling those occurring in situ in the Brentella Canal of Venice Lagoon.

  12. Levels of polychlorinated biphenyls in foods from Catalonia, Spain: estimated dietary intake.

    Science.gov (United States)

    Llobet, Juan M; Bocio, Ana; Domingo, Jose L; Teixidó, Angel; Casas, Conrad; Müller, Lutz

    2003-03-01

    From June to August 2000, food samples were randomly acquired in seven cities in Catalonia, Spain. Polychlorinated biphenyl (PCB) concentrations were determined for 108 samples of vegetables, fruits, pulses, cereals, fish and shellfish, meats and meat products, eggs, milk and dairy products, and oils and fats. Levels of 11 PCB congeners (IUPAC 28, 52, 77, 101, 105, 118, 126, 138, 153, 169, and 180) were determined by high-resolution gas chromatography-high-resolution mass spectrometry. For toxic equivalent (TEQ) calculations, World Health Organization (WHO) toxicity equivalent factors (WHO-TEFs) were used. The highest levels of most congeners were found in fish and shellfish (11,864.18 ng/kg [wet weight]), and the next highest levels, which were substantially lower, were found in milk and dairy products (674.50 ng/kg [wet weight]). For the general population of Catalonia, the total dietary intake of PCBs was found to be 150.13 pg WHO-TEQ/day. The largest contribution to this intake came from fish and shellfish (82.87 pg WHO-TEQ/day) and dairy products (29.38 pg WHO-TEQ per day). A relatively large contribution was also noted for cereals (11.36 pg WHO-TEQ/day). Among the PCB congeners determined in this study, PCB 126 showed the largest contribution to total TEQ intake (50.56%). The data obtained in this study should be useful in risk assessment with regard to human PCB exposure through food in Catalonia.

  13. Levels of organochlorine pesticides, polychlorinated biphenyls and polybrominated diphenyl ethers in fish species from Kahramanmaras, Turkey.

    Science.gov (United States)

    Erdogrul, Ozlem; Covaci, Adrian; Schepens, Paul

    2005-07-01

    The levels of organohalogenated contaminants, such as organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were measured in four fish species (Acanthobrama marmid (kalashpa), Cyprinus carpio (carp), Chondrostoma regium (nose-carp), and Silurus glanis (wels)) from the Sir Dam Lake, Kahramanmaras, Turkey. These species were selected for their characteristic feeding behaviour and their importance to local human fish consumption. DDTs were the predominant organohalogenated contaminants in all species, with the p,p'-DDE contributing to more than 90% to the total DDTs. Other OCPs, such as hexachlorocyclohexane (HCH) isomers, chlordanes and hexachlorobenzene (HCB) were found at much lower levels in all five species. The levels of PCBs and PBDEs (on wet weight basis) were lower than in similar species from European or American freshwater systems. PBDE data were measured for the first time in fish species from Turkish environment. Lipid-based concentrations of OCPs, PCBs and PBDEs were higher in wels than in the other species and this was related to its piscivorous feeding mode and to its higher lipid content. Contrarily, concentrations of pollutants in nose-carp were the lowest, in agreement with its more herbivorous diet. A preferential accumulation in muscle compared to liver was observed for all OCPs, PCBs, and PBDEs in wels and carp, while in nose-carp, a preferential accumulation in liver was observed only for PBDEs, p,p'-DDT and PCBs. Racemic amounts for alpha-HCH were measured in all investigated muscle and liver samples, except for carp muscle.

  14. Relation of polychlorinated biphenyls to birthweight and gestational age in the offspring of occupationally exposed mothers

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, P.R.; Stelma, J.; Lawrence, C.E.

    1984-09-20

    A study was made of the relation between occupational exposure of women to high homolog polychlorinated biphenyls (PCB) and birthweight and gestational age among the live offspring of these workers. In 1982 interviews were conducted with 200 women who had held jobs with direct PCB exposure. A comparison was made with 205 women who had never held such a job. When all births occurring to mothers following exposure to PCBs were considered, the unadjusted mean birthweight in the direct exposure group was 96 grams less than the comparison group. No differences in gestational age were seen between groups. The birthweight difference was reduced to 41 grams following adjustment for potential confounding factors. In a parallel analysis using a continuous exposure variable estimate generated from an independently derived serum PCB prediction model, no effect of PCBs was noted on birthweight or gestational age using either crude or adjusted analyses. The authors conclude that no evidence for a biologically meaningful effect of high homolog PCBs on gestational age or birthweight exists.

  15. Hard cap espresso extraction-stir bar preconcentration of polychlorinated biphenyls in soil and sediments.

    Science.gov (United States)

    Gallart-Mateu, Daniel; Pastor, Agustín; de la Guardia, Miguel; Armenta, Sergio; Esteve-Turrillas, Francesc A

    2017-02-01

    A Nespresso(©) hard cap espresso machine has been employed for the quantitative extraction of polychlorinated biphenyls (PCBs) from sediments and soils. Sample extraction was performed from five grams of sample in less than 40 s, with 200 mL ethanol 40% (v/v) in water and PCBs were concentrated using stir bar sorptive extraction (SBSE) and determined by thermal desorption-gas chromatography-tandem mass spectrometry (TD-GC-MS-MS). Eleven PCB congeners (28, 52, 77, 80, 81, 101, 118, 138, 153,169, and 180) were determined in soils and sediments with limits of quantification in the 0.03-0.08 ng g(-1) range. Extraction efficiency was established by the analysis of soil samples spiked with the studied PCBs at concentrations from 0.1 to 10.0 ng g(-1), obtaining quantitative recoveries from 81 to 120% and an adequate precision with relative standard deviations lower than 20%. Certified reference materials and natural samples were analyzed by the proposed hard cap espresso extraction and results were compared with those provided by a reference procedure based on pressurized solvent extraction, obtaining statistically comparable results. Therefore, the use of a hard cap espresso machine in tandem with SBSE and TD-GC-MS-MS allowed a simple, sensitive and quantitative determination of PCBs.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  19. [Source apportionment of dioxin-like polychlorinated biphenyls in soil of the modern Yellow River Delta].

    Science.gov (United States)

    Liu, Jing; Cui, Zhao-jie; Fan, Guo-lan; Xu, Hong-yu

    2007-12-01

    The concentrations of 12 dioxin-like polychlorinated biphenyls (PCBs) in twenty two soil samples collected from modern Yellow River Delta were determined by dual capillary GC-ECD associated with GC-MS. Principle component analysis (PCA) was applied in analysing the dioxin-like PCBs data to obtain types, sources, percentages of source contribution and the congener composition of PCBs in the Delta on the congener level. The results indicated that four types of PCBs contamination sources affecting the PCBs distribution pattern were apportioned in the Delta. The first source was water runoff (non-point source), which was from the industrial production and use by the enterprises along the Yellow River, and it contributed 49.6% of the total contamination burden in the Delta, its dioxin-like PCBs profile was similar to native PCBs and Aroclorl221; the second and third types of PCBs sources were point sources, whose percentages of contribution were 15.0% and 10.1% respectively, the composition of the second source was similar to that of Aroclor1221 and Aroclor1242, the composition of the third source was similar to that of Aroclor1260; the fourth source is believed to be non-point source which was from the atmospheric dry and wet precipitation, it contributed 8.4%, its profile have similarity composition of the integration of Aroclor1242, Aroclor1248 and Aroclor1260.

  20. A review of the neurotoxicity of non-dioxin-like polychlorinated biphenyls

    Energy Technology Data Exchange (ETDEWEB)

    Seegal, R. [Albany Univ., NY (United States). Wadsworth Center, New York State Dept. of Health and School of Public Health

    2004-09-15

    It is perhaps both presumptuous and somewhat nostalgic for me to present research findings from both myself and others describing the changes in central nervous system (CNS) function that occur following exposure to non-dioxin-like polychlorinated biphenyls (PCBs) at the 2004 Dioxin meeting. Presumptuous because my presentation occurs during this meeting where the majority of the research is concerned with the consequences of exposure to dioxins (the most toxic substance produced by man) and nostalgic because, in 1992, I presented some of my earliest work demonstrating that non-dioxin-like PCBs were capable of significantly altering neurochemical function. Much has changed in the intervening twelve years. Laboratories in the United States and Europe now routinely study and describe the neurotoxicological effects of developmental and in vitro exposure to non-dioxin-like PCBs. My task will be to briefly describe the highlights of that research and suggest additional approaches that will hopefully increase our ability to understand the mechanisms of action of non-dioxin-like PCBs on neuronal and behavioral function in populations of exposed humans.

  1. Presence of polychlorinated biphenyls (PCBs) in bottled drinking water in Mexico City.

    Science.gov (United States)

    Salinas, Rutilio Ortiz; Bermudez, Beatriz Schettino; Tolentino, Rey Gutiérrez; Gonzalez, Gilberto Díaz; Vega y León, Salvador

    2010-10-01

    This paper describes the concentrations of seven polychlorinated biphenyls (PCBs) in bottled drinking water samples that were collected over 1 year from Mexico City in two sizes (1.5 and 19 L), using gas chromatography with an electron capture detector. PCBs 28 (0.018-0.042 μg/L), 52 (0.006-0.015 μg/L) and 101 (0.001-0.039 μg/L) were the most commonly found and were present in the majority of the samples. However, total concentrations of PCBs in bottled drinking water (0.035-0.039 μg/L) were below the maximum permissible level of 0.50 μg/L stated in Mexican regulations and probably do not represent a hazard to human health. PCBs were detectable in all samples and we recommend a monitoring program be established to better understand the quality of drinking bottled water over time; this may help in producing solutions for reducing the presence of organic contaminants.

  2. Modeling water column partitioning of polychlorinated biphenyls to natural organic matter and black carbon.

    Science.gov (United States)

    Greene, Richard W; Di Toro, Dominic M; Farley, Kevin J; Phillips, Kathy L; Tomey, Cynthia

    2013-06-18

    High volume in situ surface water samples were collected from a tidal tributary of the Delaware Estuary using an Infiltrex sampling system equipped with a 1 μm particle filter and a XAD-2 resin column. Particulate and dissolved phase polychlorinated biphenyl (PCB) congeners were analyzed using high resolution gas chromatography/high resolution mass spectrometry to obtain detection levels in the femtograms per liter range. The data were fit to a four-phase equilibrium partitioning model including freely dissolved PCB, PCB bound to particulate organic carbon (POC), PCB bound to dissolved organic carbon (DOC), and PCB bound to black carbon (BC). Isotherms were assumed to be linear for POC and DOC and nonlinear for BC. The partition coefficient between BC and dissolved PCB was assumed to depend on the dihedral angle between the phenyl rings. Following parameter optimization, the correlation coefficient between the log of the modeled and measured apparent distribution coefficient Kp,app was 0.94, and the RMSE was 0.189 log units. Including BC in the model reduces the dissolved PCB phase concentration in the water column for all congeners, especially for the non-ortho and mono-ortho substituted congeners.

  3. The uridine diphosphate glucuronosyltransferases: quantitative structure-activity relationships for hydroxyl polychlorinated biphenyl substrates

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Degao [Dalian University of Technology, Department of Environmental Science and Technology, Dalian (China)

    2005-10-01

    Quantitative structure-activity relationships (QSARs), which relate the glucuronidation of hydroxyl polychlorinated biphenyls (OH-PCBs) - catalyzed by the uridine diphosphate glucuronosyltransferases (UGTs) - to their physicochemical properties and molecular structural parameters, can be used to predict the rate constants and interpret the mechanism of glucuronidation. In this study, QSARs have been developed that use 23 semi-empirical calculated quantum chemical descriptors to predict the logarithms of the constants 1/K{sub m} and V{sub max}, related to enzyme kinetics. A partial least squares regression method was used to select the optimal set of descriptors to minimize the multicollinearity between the descriptors, as well as to maximize the cross-validated coefficient (Q{sup 2} {sub cum}) values. The key descriptors affecting log(1/K{sub m}) were E{sub lumo}- E{sub homo} (the energy gap between the lowest unoccupied molecular orbital and the highest occupied molecular orbital) and q{sub C}{sup -} (the largest negative net atomic charge on a carbon atom), while the key descriptors affecting log V{sub max} were the polarizability {alpha}, the Connolly solvent-excluded volume (CSEV), and logP (the logarithm of the partition coefficient for octanol/water). From the results obtained it can be concluded that hydrophobic and electronic aspects of OH-PCBs are important in the glucuronidation of OH-PCBs. (orig.)

  4. Sorption of polychlorinated biphenyls onto biochars derived from corn straw and the effect of propranolol.

    Science.gov (United States)

    Wang, Fei; Ren, Xinhao; Sun, Hongwen; Ma, Ling; Zhu, Hongkai; Xu, Jiayao

    2016-11-01

    The sorption of three polychlorinated biphenyls (PCBs) in single-solute and bi-solute systems in the presence of propranolol was studied on biochars at pyrolyzing temperatures of 200°C (BC200) and 700°C (BC700). Hydrophobicity and molecular planarity played a major role in PCB sorption onto BC200 and BC700, respectively. The steric hindrance caused by non-planarity made the strong specific sorption sites on BC700 less accessible to nonplanar PCBs. In bi-solute systems for BC200, propranolol monomers at an initial concentration (Cinit) of 0.8mg/L inhibited the sorption of PCB4 by competing for sorption sites. Propranolol at Cinit larger than 1.2mg/L could form hemimicelle structures on the biochar surface, providing a favorable phase for PCB4 partitioning, thereby increasing Koc up to 1.15 times. For BC700, propranolol prohibited PCB4 sorption mainly by pore-blocking, with the log Koc being reduced from 4.92 to 3.94. This study informs the application of biochar in mixture-contaminated environment.

  5. Distribution of organochlorine pesticides and polychlorinated biphenyls in Ny-(A)lesund of the Arctic

    Institute of Scientific and Technical Information of China (English)

    Ma Xindong; Wang Yanjie; Na Guangshui; Lin Zhongsheng; Zhou Chuanguang; Wang Zhen; Yao Ziwei

    2009-01-01

    Sediment, moss and animal-dropping samples were collected from pesticides (OCPs) and polychlorinated biphenyls (PCBs) in the Arctic area. OCPs and PCBs were analyzed using the capillary gas chromatography (GC-ECD). Recoveries of three surrogates were at a range of 69.5~92.2% (mean: 78.8%), 75.1~112.1% (98.5%) and 67.7~95.1% (79.5%), and the relative standard deviations were 6.7%, 8.0% and 11.3%, respectively. The major monomers of OCPs were hexachlorocyclohexanes (HCHs) and DDTs. Their concentrations were at a range of 0.86~4.50 ng/g (mean: 2.24 ng/g) and 0.22~1.09 ng/g (mean: 0.55 ng/g). The concentrations of PCBs were 0.20~3.25 ng/g (mean: 0.84 ng/g) and the major congeners were tetra-, penta-, and hexa-PCBs, which were up to 23.8%、26.7% and 32.3% of total PCBs, respectively. Based on the results of the ratio analysis and the principal component analysis, the atmospheric transport is believed be one

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

    Science.gov (United States)

    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.

  7. Oxidation of dibenzothiophene (DBT by Serratia marcescens UCP 1549 formed biphenyl as final product

    Directory of Open Access Journals (Sweden)

    de Araújo Hélvia W

    2012-05-01

    Full Text Available Abstract Background The desulphurization of dibenzothiophene (DBT, a recalcitrant thiophenic fossil fuel component by Serratia marcescens (UCP 1549 in order for reducing the Sulphur content was investigated. The Study was carried out establishing the growth profile using Luria Bertani medium to different concentrations of DBT during 120 hours at 28°C, and orbital Shaker at 150 rpm. Results The results indicated that concentrations of DBT 0.5, 1.0 and 2.0 mM do not affected the growth of the bacterium. The DBT showed similar Minimum Inhibitory Concentration (MIC and Minimum Bactericidal Concentration (MCB (3.68 mM. The desulphurization of DBT by S. marcescens was used with 96 hours of growth on 2 mM of DBT, and was determined by gas chromatography (GC and GC-mass spectrometry. In order to study the desulphurization process by S. marcescens was observed the presence of a sulfur-free product at 16 hours of cultivation. Conclusions The data suggests the use of metabolic pathway “4S” by S. marcescens (UCP 1549 and formed biphenyl. The microbial desulphurization process by Serratia can be suggest significant reducing sulphur content in DBT, and showed promising potential for reduction of the sulfur content in diesel oil.

  8. Temporal Trends of Hexabromocyclododecane, Polybrominated Diphenyl Ethers and Polychlorinated Biphenyls in Ringed Seals from East Greenland

    DEFF Research Database (Denmark)

    Vorkamp, Katrin; Riget, Frank Farsø; Bossi, Rossana

    2011-01-01

    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. R-HBCD was the only diastereoisomer consistently above levels of quantification and showed a signifi......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. R-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 þ6.1%. 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...

  9. Anaemia, hypothyroidism and immune suppression associated with polychlorinated biphenyl exposure in bottlenose dolphins (Tursiops truncatus).

    Science.gov (United States)

    Schwacke, Lori H; Zolman, Eric S; Balmer, Brian C; De Guise, Sylvain; George, R Clay; Hoguet, Jennifer; Hohn, Aleta A; Kucklick, John R; Lamb, Steve; Levin, Milton; Litz, Jenny A; McFee, Wayne E; Place, Ned J; Townsend, Forrest I; Wells, Randall S; Rowles, Teresa K

    2012-01-01

    Polychlorinated biphenyls (PCBs), persistent chemicals widely used for industrial purposes, have been banned in most parts of the world for decades. Owing to their bioaccumulative nature, PCBs are still found in high concentrations in marine mammals, particularly those that occupy upper trophic positions. While PCB-related health effects have been well-documented in some mammals, studies among dolphins and whales are limited. We conducted health evaluations of bottlenose dolphins (Tursiops truncatus) near a site on the Georgia, United States coast heavily contaminated by Aroclor 1268, an uncommon PCB mixture primarily comprised of octa- through deca-chlorobiphenyl congeners. A high proportion (26%) of sampled dolphins suffered anaemia, a finding previously reported from primate laboratory studies using high doses of a more common PCB mixture, Aroclor 1254. In addition, the dolphins showed reduced thyroid hormone levels and total thyroxine, free thyroxine and triiodothyronine negatively correlated with PCB concentration measured in blubber (p = 0.039, dolphins when compared with previously sampled reference sites, and therefore probably did not contribute to the observed correlations. Our results clearly demonstrate that dolphins are vulnerable to PCB-related toxic effects, at least partially mediated through the endocrine system. The severity of the effects suggests that the PCB mixture to which the Georgia dolphins were exposed has substantial toxic potential and further studies are warranted to elucidate mechanisms and potential impacts on other top-level predators, including humans, who regularly consume fish from the same marine waters.

  10. Tracking chiral polychlorinated biphenyl sources near a hazardous waste incinerator: fresh emissions or weathered revolatilization?

    Science.gov (United States)

    Asher, Brian J; Ross, Matthew S; Wong, Charles S

    2012-07-01

    The Swan Hills Treatment Centre (SHTC), located in central Alberta, is the primary facility in Canada for incinerating polychlorinated biphenyls (PCBs). Past studies have shown significant contamination by PCBs and other pollutants of the immediate surrounding region. However, it is unclear whether the major source of contamination to the region's atmosphere is historical release incidents or long-term emissions. To answer this question, concentrations of PCBs and enantiomer fractions of several PCB congeners were determined in soil and air, via polyurethane foam passive samplers, over several seasons between 2005 and 2008. Concentrations in both media were highest for samples collected closest to the SHTC, demonstrating a concentration profile typical of a point source. Enantiomer analysis revealed racemic profiles in air for all congeners, while soil was significantly nonracemic for PCB 95, indicating significant microbial degradation of this congener. However, the primary source of this congener, and likely others, in the surrounding atmosphere is recent and continual releases from the SHTC, rather than the release of weathered PCBs previously deposited to local soils. In addition, enantiomer compositions for PCBs 95 and 149 yielded minimum biotransformation half-lives of 25 and 97 years, respectively, suggesting an expected gradual decline in the region's PCB load once fresh inputs cease.

  11. Plasma Levels of Polychlorinated Biphenyls, Non-Hodgkin Lymphoma, and Causation

    Directory of Open Access Journals (Sweden)

    Michael D. Freeman

    2012-01-01

    Full Text Available Polychlorinated biphenyls (PCBs are synthetic chlorinated hydrocarbons that have extensively polluted the environment and bioaccumulated in the food chain. PCBs have been deemed to be probable carcinogens by the Environmental Protection Agency, and exposure to high levels of PCBs has been consistently linked to increased risk of non-Hodgkin lymphoma (NHL. In the present article we present a forensic epidemiologic evaluation of the causal relationship between NHL and elevated PCB levels via application of the Bradford-Hill criteria. Included in the evaluation is a meta-analysis of the results of previously published case-control studies in order to assess the strength of association between NHL and PCBs, resulting in an odds ratio in which the lowest percentile PCB concentration (quartile, quintile, or tertile has been compared with the highest percentile concentration in the study groups. The weight-adjusted odds ratio for all PCB congeners was 1.43 with a 95% confidence interval of 1.31 to 1.55, indicating a statistically significant causal association with NHL. Because of the lack of an unexposed comparison group, a rationale for the use of a less than 2.0 relative risk causal contribution threshold is presented herein, including an ecologic analysis of NHL incidence and PCB accumulation (as measured by sales volume over time. The overall results presented here indicate a strong general causal association between NHL and PCB exposure.

  12. Levels and distributions of polychlorinated biphenyls in sewage sludge of urban wastewater treatment plants

    Institute of Scientific and Technical Information of China (English)

    GUO Li; ZHANG Bing; XIAO Ke; ZHANG Qinghua; ZHENG Minghui

    2009-01-01

    Concentrations of polychlorinated biphenyls (PCBs) have been measured in sewage sludge samples from 8 urban wastewater treatment plants in Beijing, China. The PCB congeners were analyzed by isotope dilution high resolution gas chromatography/high resolution mass spectrometry method. The concentration of PCBs ranged from 65.6 to 157 ng/g dry weight (dw), with a mean value of 101 ng/g dw. The dioxin-like PCB WHO-TEQs (World Health Organization-Toxic Equivalents) of the sludge were lower than 1 pg /g dw. Consequently, all the concentrations of PCBs in sludge samples were below the upper limit for land application according to the Chinese legislation law for agriculture use. The PCB homologue profiles in sludge samples were dominated by tri-CBs and tetra-CBs. Similar distributions have been found in one of the Chinese PCB commercial products. The patterns of dioxin-like and indicator congeners observed in this study were quite similar in all samples. The predominant congener for dioxin-like and indicator PCBs were PCB-118 and PCB-28, respectively, while PCB-126 had the highest TEQ value.

  13. Concentrations and Toxic Equivalency of Polychlorinated Biphenyls in Polish Wastewater Treatment Plant Effluents.

    Science.gov (United States)

    Urbaniak, Magdalena; Kiedrzyńska, Edyta

    2015-10-01

    Wastewater treatment plants (WWTPs) are widely recognized as important sources of toxic contaminants such as polychlorinated biphenyls (PCBs). An example is given in the present paper, where concentrations of 12 dioxin-like PCBs (dl-PCBs) congeners were investigated in effluents from 14 WWTPs of different sizes, using gas chromatography tandem-mass spectrometry. The results obtained demonstrate that the smallest WWTPs are characterized by the highest total dl-PCB concentration of 102.69 pg/L, roughly twice those of medium-size and large WWTPs, i.e. 41.14 and 48.29 pg/L, respectively. In all cases, the concentrations obtained were generated mostly by increased contributions of PCB-77, PCB-105 and PCB-118 which constituted 48 %-59 % of the mean dl-PCB concentration. The results also reveal a predominance of mono-ortho over non-ortho PCBs. All three types of WWTP effluent were found to have similar toxic equivalency (TEQ) values, ranging from 0.31 for large to 0.37 pg TEQ/L for medium WWTPs.

  14. Uptake of polychlorinated biphenyls and organochlorine pesticides from soil and air into radishes (Raphanus sativus)

    Energy Technology Data Exchange (ETDEWEB)

    Mikes, Ondrej; Cupr, Pavel [RECETOX, Research Centre for Environmental Chemistry and Ecotoxicology, Masaryk University, Kamenice 126/3, 625 00 Brno (Czech Republic); Trapp, Stefan [Department of Environmental Engineering, Technical University of Denmark, Miljoevej 113, DK-2800 Kgs. Lyngby (Denmark); Klanova, Jana [RECETOX, Research Centre for Environmental Chemistry and Ecotoxicology, Masaryk University, Kamenice 126/3, 625 00 Brno (Czech Republic)], E-mail: klanova@recetox.muni.cz

    2009-02-15

    Uptake of organochlorine pesticides and polychlorinated biphenyls from soil and air into radishes was measured at a heavily contaminated field site. The highest contaminant concentrations were found for DDT and its metabolites, and for {beta}-hexachlorocyclohexane. Bioconcentration factor (BCF, defined as a ratio between the contaminant concentration in the plant tissue and concentration in soil) was determined for roots, edible bulbs and shoots. Root BCF values were constant and not correlated to log K{sub OW}. A negative correlation between BCF and log K{sub OW} was found for edible bulbs. Shoot BCF values were rather constant and varied between 0.01 and 0.22. Resuspended soil particles may facilitate the transport of chemicals from soil to shoots. Elevated POP concentrations found in shoots of radishes grown in the control plot support the hypothesis that the uptake from air was more significant for shoots than the one from soil. The uptake of POPs from air was within the range of theoretical values predicted from log K{sub OA}. - Uptake from air represented for majority of persistent organochlorines a dominant pathway into shoots while uptake from soil was dominant for roots.

  15. Polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs) and neuropsychological status among older adults in New York.

    Science.gov (United States)

    Fitzgerald, Edward F; Shrestha, Srishti; Gomez, Marta I; McCaffrey, Robert J; Zimmerman, Earl A; Kannan, Kurunthachalam; Hwang, Syni-an

    2012-01-01

    Polybrominated diphenyl ethers (PBDEs) are emerging environmental contaminants, but little is known about their possible human health effects. The objective of this study is to evaluate the association between exposure to PBDEs and neuropsychological function among older adults and the possibility of effect modification with polychlorinated biphenyls (PCBs). Serum samples were analyzed for concentrations of 9 PBDE and 30 PCB congeners and 34 tests of cognitive and motor function, affective state, and olfactory function were assessed among 144 men and women of 55-74 years of age. After adjustment for relevant confounders, no overall associations were observed between the sum of the PBDE congener concentrations in serum (∑ PBDE) and scores on the neuropsychological tests. However, statistically significant interactions were found between PBDEs and PCBs for some measures of verbal learning and memory. Among persons with ∑ PCB concentrations at or above the median of 467ppb (lipid basis), an increase in ∑ PBDE concentrations from the 25th to 75th percentile was associated with decreases between 7% and 12% on scores for certain subscales of the California Verbal Learning Test. In contrast, no statistically significant associations were observed for PBDEs among persons with ∑ PCB levels below the median. The results suggest that PBDEs and PCBs may interact to affect verbal memory and learning among persons 55-74 years old. This is the first study to evaluate the neuropsychological effects of PBDEs in adults and the possibility of synergy with PCBs in humans.

  16. Spatial trends of organochlorinated pesticides, polychlorinated biphenyls, and polybrominated diphenyl ethers in Atlantic Anguillid eels.

    Science.gov (United States)

    Byer, Jonathan D; Lebeuf, Michel; Alaee, Mehran; Stephen, Brown R; Trottier, Steve; Backus, Sean; Keir, Michael; Couillard, Catherine M; Casselman, John; Hodson, Peter V

    2013-02-01

    The bioaccumulation of lipophilic contaminants such as polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs) can result in a reduction in fitness and spawner quality in eels and may be a factor in Anguillid sp. population declines. Contaminant concentrations in eels have been studied extensively in Europe, but data for American eels are severely lacking. Concentrations of PCBs, OCPs, and PBDEs were determined in American eel from eastern Canada and New York, USA, along with European eel from Belgium. Principal component analysis revealed that eels captured in the St. Lawrence estuary were a mixture of upstream migrants from the St. Lawrence River watershed, and fish captured in local tributaries. Contaminant concentrations were dependent on origin, related to the local environment, and were lower than historic values. In Canada, concentrations of OCPs and PCBs in eel tissues were below the Canadian human consumption guidelines for contaminants in fish, indicating that the current risk to consumers is low. However, concentrations of PCBs, total DDT, and mirex in eels from L. Ontario and the upper St. Lawrence R. were above Great Lakes guidelines for the protection of piscivorous predators. Concentrations of penta-BDE homologs exceeded the Canadian guideline for environmental quality in over half of the eels in this study, but concentrations of the other homolog groups were below the guideline.

  17. Environmental polychlorinated biphenyl exposure and cytochromes P450 in raccoons (Procyon lotor).

    Science.gov (United States)

    Smith, Philip N; Bandiera, Stelvio M; Skipper, Sherry L; Johnson, Kevin A; McMurry, Scott T

    2003-02-01

    An investigation involving raccoons as a sentinel species at the Paducah Gaseous Diffusion Plant (PGDP) and Ballard Wildlife Management Area in western Kentucky (USA) delineated the extent of exposure to polychlorinated biphenyls (PCBs). Three separate measures of hepatic cytochrome P450 (CYP) induction were used to evaluate raccoon physiological responses to PCB exposure. Hepatic CYP induction was estimated via determination of total CYP, dealkylase activities, and immunoreactive proteins. There were no differences in raccoon biomarker responses between study sites. Significant relationships between and among PCB residues and biomarkers indicated that hepatic CYP induction had occurred in response to PCB exposure. Pentoxyresorufin O-deethylase (PROD) activity, CYP1A1, and CYP1A2 were biomarkers most closely associated with PCB exposure. The rank order of responses was CYP1A1 > CYP1A2 > PROD > ethoxyresorufin O-deethylase (EROD) as related to raccoon liver PCB concentrations, whereas the order was CYP1A1 > PROD > EROD > CYP1A2 when regressed with total PCB concentrations in abdominal fat.

  18. Biological uptake of polychlorinated biphenyls by Macoma balthica from sediment amended with activated carbon

    Science.gov (United States)

    McLeod, Pamela B.; van den Heuvel-Greve, Martine J.; Luoma, S.N.; Luthy, R.G.

    2007-01-01

    This work characterizes the efficacy of activated carbon amendment in reducing polychlorinated biphenyl (PCB) bioavailability to clams (Macoma balthica) from field-contaminated sediment (Hunters Point Naval Shipyard, San Francisco Bay, CA, USA) Test methods were developed for the use of clams to investigate the effects of sediment amendment on biological uptake. Sediment was mixed with activated carbon for one month. Bioaccumulation tests (28 d) were employed to assess the relationships between carbon dose and carbon particle size on observed reductions in clam biological uptake of PCBs. Extraction and cleanup protocols were developed for the clam tissue. Efficacy of activated carbon treatment was found to increase with both increasing carbon dose and decreasing carbon particle size. Average reductions in bioaccumulation of 22, 64, and 84% relative to untreated Hunters Point sediment were observed for carbon amendments of 0.34, 1.7, and 3.4%, respectively. Average bioaccumulation reductions of 41, 73, and 89% were observed for amendments (dose = 1.7% dry wt) with carbon particles of 180 to 250, 75 to 180, and 25 to 75 ??m, respectively, in diameter, indicating kinetic phenomena in these tests. Additionally, a biodynamic model quantifying clam PCB uptake from water and sediment as well as loss through elimination provided a good fit of experimental data. Model predictions suggest that the sediment ingestion route contributed 80 to 95% of the PCB burdens in the clams. ?? 2007 SETAC.

  19. Evaluation of the immunotoxicity of low-level PCB (polychlorinated biphenyl) exposure in the rat

    Energy Technology Data Exchange (ETDEWEB)

    Smialowicz, R.J.; Andrews, J.E.; Riddle, M.M.; Rogers, R.R.; Luebke, R.W.

    1989-01-01

    Weanling male Fischer 344 rats were exposed daily by gastric intubation for up to 15 weeks to the polychlorinated biphenyl (PCB) Aroclor 1254 at 0.1, 1, 10, or 25 mg/kg body weight. At 5, 10 and 15 weeks groups of rats were killed and immune functions were evaluated. The immune parameters examined included the following: body and lymphoid organ weights, mitogen stimulated lymphoproliferative (LP) responses, natural killer (NK) cell activity, mixed lymphocyte reaction (MLR), and cytotoxic T lymphocyte (CTL) response. After 10 and 15 weeks of dosing body weights were reduced in rats receiving 25 mg/kg PCB while thymus weights were decreased in rats receiving 10 and 25 mg/kg. NK cell activity was reduced in rats dosed for 15 weeks at 10 and 25 mg/kg. The LP response to phytohemagglutinin was enhanced in rats dosed for 15 weeks at 25 mg/kg PCB. Exposure of rats to PCB did not affect the MLR or CTL responses. Other groups of rats were exposed to cyclophosphamide (CY) and served as positive controls for the immune assays employed. CY induced alterations in all of the immune parameters measured, indicating that this is a sensitive battery of immune function tests which is capable of detecting immune alterations in the rat.

  20. Polychlorinated Biphenyls Induce Mitochondrial Dysfunction in SH-SY5Y Neuroblastoma Cells.

    Directory of Open Access Journals (Sweden)

    Stefania Cocco

    Full Text Available Chronic exposure to polychlorinated biphenyls (PCBs, ubiquitous environmental contaminants, can adversely affect the development and function of the nervous system. Here we evaluated the effect of PCB exposure on mitochondrial function using the PCB mixture Aroclor-1254 (A1254 in SH-SY5Y neuroblastoma cells. A 6-hour exposure to A1254 (5 μg/ml reduced cellular ATP production by 45%±7, and mitochondrial membrane potential, detected by TMRE, by 49%±7. Consistently, A1254 significantly decreased oxidative phosphorylation and aerobic glycolysis measured by extracellular flux analyzer. Furthermore, the activity of mitochondrial protein complexes I, II, and IV, but not V (ATPase, measured by BN-PAGE technique, was significantly reduced after 6-hour exposure to A1254. The addition of pyruvic acid during exposure to A1254 significantly prevent A1254-induced cell injury, restoring resting mitochondrial membrane potential, ATP levels, oxidative phosphorylation and aerobic glycolysis. Furthermore, pyruvic acid significantly preserved the activity of mitochondrial complexes I, II and IV and increased basal activity of complex V. Collectively, the present results indicate that the neurotoxicity of A1254 depends on the impairment of oxidative phosphorylation, aerobic glycolysis, and mitochondrial complexes I, II, and IV activity and it was counteracted by pyruvic acid.

  1. Polychlorinated biphenyls in sediments and fish species from the Murchison Bay of Lake Victoria, Uganda.

    Science.gov (United States)

    Ssebugere, Patrick; Sillanpää, Mika; Wang, Pu; Li, Yingming; Kiremire, Bernard T; Kasozi, Gabriel N; Zhu, Chaofei; Ren, Daiwei; Zhu, Nali; Zhang, Haidong; Shang, Hongtao; Zhang, Qinghua; Jiang, Guibin

    2014-06-01

    Polychlorinated biphenyls (PCBs) were determined in sediments and two fish species collected from the Murchison Bay in Lake Victoria, using high resolution gas chromatography coupled to a high resolution mass spectrometer. Total PCB concentrations (Σ18PCBs) varied widely with mean values ranging from 777 to 4325pg g(-1) dry weight (dw) for sediments and 80 to 779pg g(-1) wet weight (ww) for fish. The PCB levels in the sediments were significantly higher at the station closest to Nakivubo channel, presumably due to effluents discharged by the channel, which may contain domestically produced commercial PCB mixtures. For fish, the concentrations in Nile perch (Lates niloticus) were significantly greater than those in Nile tilapia (Oreochromis niloticus) at all study stations, possibly due to dietary differences among species. World Health Organization-toxic equivalents (WHO2005-TEQs) for the dioxin-like PCBs were 0.04-0.64pg g(-1) dw and 0.01-0.39pg g(-1) ww for sediments and fish, respectively. The non-ortho PCBs exhibited the highest contribution to the Σ12TEQs (>75%) compared to the mono-ortho PCBs in both fish species. The TEQs in the present study were lower than many reported worldwide in literature for fish and were within the permissible level recommended by the European Commission, implying that the fish did not pose health hazards related to PCBs to the consumers.

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

    Science.gov (United States)

    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.

  3. Bioavailability and bioaccumulation of sediment-bound polychlorinated biphenyls to carp.

    Science.gov (United States)

    Gaillard, Juliette; Banas, Damien; Thomas, Marielle; Fournier, Agnès; Feidt, Cyril

    2014-06-01

    The relative bioavailability of sediment-bound polychlorinated biphenyls (PCBs 138, 153, and 180) from a local contaminated site was examined using an in vivo carp model. Surface sediment from the PCB-contaminated site and spiked canola oil containing equivalent masses of PCBs were respectively incorporated in the sediment-dosed diets and oil-dosed diets at 3 dose levels resulting in 6 experimental diets. Juvenile carps (n = 90) were divided in 18 tanks (5 fish × 6 treatments × 3 tanks). Fish were fed the control diet during the adaptation period (15 d). Next, 1 fish was sampled in each tank and muscle tissues were combined in control groups. During the exposure period (15 d), the remaining fish were fed with 1 of the 6 experimental diets. At the end of the experiment, fish were sampled and muscle tissues were combined for each tank. The PCBs were monitored in feed and fish muscle. For both the contaminated sediment and spiked canola oil groups, concentrations of PCBs 138, 153, and 180 in muscle linearly increased with concentrations in food, with similar intercepts and slopes. In the present study, the sediment-bound PCBs were as bioavailable as those spiked into canola oil and fed to carp in a standard diet.

  4. Electron ionization mass spectral fragmentation study of sulfation derivatives of polychlorinated biphenyls

    Directory of Open Access Journals (Sweden)

    Robertson Larry W

    2009-03-01

    Full Text Available Abstract Background Polychlorinated biphenyls are persistent organic pollutants that can be metabolized via hydroxylated PCBs to PCB sulfate metabolites. The sensitive and selective analysis of PCB sulfate monoesters by gas chromatography-mass spectrometry (GC-MS requires their derivatization, for example, as PCB 2,2,2-trichloroethyl (TCE sulfate monoesters. To aid in the identification of unknown PCB sulfate metabolites isolated from biological samples, the electron impact MS fragmentation pathways of selected PCB TCE sulfate diesters were analyzed and compared to the fragmentation pathways of the corresponding methoxylated PCBs. Results The most abundant and characteristic fragment ions of PCB TCE sulfate diesters were formed by releasing CHCCl3, SO3, HCl2 and/or CCl3 from the TCE sulfate moiety and Cl2, HCl, ethyne and chloroethyne from an intermediate phenylcyclopentadienyl cation. The fragmentation pattern depended on the degree of chlorination and the position of the TCE sulfate moiety (i.e., ortho vs. meta/para to the second phenyl ring, but were independent of the chlorine substitution pattern. These fragmentation pathways are similar to the fragmentation pathways of structurally related methoxylated PCBs. Conclusion Knowledge of the fragmentation patterns of PCB TCE sulfate diesters will greatly aid in determining the position of sulfate moiety (ortho vs. meta/para of unknown PCB sulfate metabolites isolated from environmental or laboratory samples.

  5. Determination of polychlorinated biphenyls (PCBs) in insulating oil by cocktail PCB ELISA

    Energy Technology Data Exchange (ETDEWEB)

    Goda, Y.; Hirobe, M.; Fujimoto, S. [Japan EnviroChemicals Ltd., Tokyo (Japan); Tomita, J.; Nishikiori, M.; Nakajima, T. [Tokyo Electric Power Environmental Engineering Co. Inc., Tokyo (Japan); Rubio, F. [Abraxis LLC, Warminster, PA (United States); Takigami, H. [National Inst. for Environmental Studies, Tsukuba (Japan); Sakai, S. [Kyoto Univ., Kyoto (Japan). Environment Preservation Centre; Ike, M.; Fujita, M. [Osaka Univ., Osaka (Japan). Graduate School of Engineering

    2005-07-01

    This paper described a novel cocktail polychlorinated biphenyl (PCB) enzyme-linked immunosorbent assay (ELISA) designed as a simple pretreatment method for the determination of PCBs in insulating oils. Oil samples were treated with hexane and dimethyl sufloxide (DMSO) and mixed. Hexane layers were then removed, and freshly prepared hexane was added. The DMSO layer was then diluted with an aqueous solution and extracted with hexane. After being dehydrated, the hexane layer was sulfonated with a sulfuric reagent and washed. Standard or pretreated PCBs were then dissolved and diluted in 100 per cent DMSO and added to distilled water prior to the ELISA assay. A horseradish peroxidase conjugate and an anti-PCB antibody coupled with magnetic particles were added for the assay. A magnetic rack was used to separate the reaction mixture. A colouring reagent was then added. A total of 26 insulating oils contaminated with PCBs were determined using the new cocktail method and compared with data obtained from traditional gas chromatograph electron capture detector (GC-ECD) data. Results showed that the values of both the cocktail and general PCB ELISA were well correlated with the CG-ECD data. It was concluded that combining cocktail PCB ELISA with the developed pretreatment method provided accurate results. 3 refs., 4 tabs., 2 figs.

  6. Heavy metals and polychlorinated biphenyls (PCBs) sedimentation in the Lianhua Mountain Reservoir, Pearl River Delta, China.

    Science.gov (United States)

    Huang, Jingyu; Amuzu-Sefordzi, Basil; Li, Ming

    2015-05-01

    The Pearl River Delta is one of the biggest electronics manufacturing regions in the world. Due to the presence of abandoned industrial sites and the proliferation of large-scale electronics companies in the past four decades, it is therefore imperative to investigate the extent of heavy metals and polychlorinated biphenyls (PCBs) contamination in the region. Spatial and temporal distribution of heavy metals (Cr, Cu, Ni, Pb, and Zn) and PCBs (PCB28, PCB52, PCB101, PCB118, PCB138, PCB153, and PCB180) in the Lianhua Mountain reservoir in the Pearl River Delta, Dongguan City, China were examined based on a sedimentary profile analysis. Higher concentrations of the heavy metals detected were recorded in bottom sediments whereas 70% of the detected PCBs recorded maximum concentrations in top sediments. The geo-accumulation indices (Igeo) indicate that the study area is uncontaminated to moderately contaminated. Also, the integrated pollution indices (IPI) were above 1, except Pb, which shows that the study area is contaminated with heavy metals from anthropogenic sources. The concentrations of individual heavy metals and PCBs over a period of 60 years were also analyzed in order to establish a historical trend of pollution in the study area. This study provides baseline information on the level and historical trend of heavy metals and PCBs pollution in the study area.

  7. RETRACTED — Preparation of helical biphenyl polyurethane and its low power consumption thermo-optic switch

    Science.gov (United States)

    Wang, Qing; Qiu, Fengxian; Yang, Dongya; Cao, Guorong; Guan, Yijun; Shen, Qiang; Zhuang, Lin; Cao, Zhijuan; Ye, Feiyan

    2013-04-01

    Azo chromophore molecule (NDPD) and helical biphenyl polyurethane (HBPU) were prepared. The chemical structures of NDPD and HBPU were characterized by FTIR and UV-vis spectroscopy. The measurements of refractive index, thermo-optic coefficient (dn/dT), transmission loss, refractive index dispersions and Sellmeyer coefficients of HBPU were measured using ATR technique, CCD digital imaging devices and Sellmeyer equation. The results showed that HBPU would be useful for the design of high performance digital optical switch. The prepared HBPU was utilized as core material to propose a Y-branch thermo-optic switch, which was based on thermo-optic effect of HBPU at the infrared communication wavelength of 1.55 μm. With branching angle of 0.143° and the finite difference beam propagation method (FD-BPM), the polymeric thermo-optic switch was simulated. The simulation results indicated that the device has a low switching power of 1.68 mW and a switching response time of 7.0 ms.

  8. Polychlorinated biphenyls in freshwater salmonids from the Kerguelen Islands in the Southern Ocean

    Energy Technology Data Exchange (ETDEWEB)

    Jaffal, A. [Laboratoire d' Eco-Toxicologie, EA 2069 Vignes et Vins de Champagne, Universite de Reims Champagne-Ardenne, F51687 Reims Cedex 2 (France); Givaudan, N. [UMR8079, CNRS, Orsay F-91405 (France); Univ Paris-Sud, Ecologie Systematique et Evolution, Orsay F-91405 (France); Betoulle, S. [Laboratoire d' Eco-Toxicologie, EA 2069 Vignes et Vins de Champagne, Universite de Reims Champagne-Ardenne, F51687 Reims Cedex 2 (France); Terreau, A. [IPEV Institut Polaire Francais, F29280 Plouzane (France); Paris-Palacios, S.; Biagianti-Risbourg, S. [Laboratoire d' Eco-Toxicologie, EA 2069 Vignes et Vins de Champagne, Universite de Reims Champagne-Ardenne, F51687 Reims Cedex 2 (France); Beall, E. [ECOBIOP, UMR 1224 INRA-Universite de Pau-Pays de l' Adour F63310 St-Pee-sur-Nivelle (France); Roche, H., E-mail: helene.roche@u-psud.fr [UMR8079, CNRS, Orsay F-91405 (France); Univ Paris-Sud, Ecologie Systematique et Evolution, Orsay F-91405 (France)

    2011-05-15

    The Subantarctic Kerguelen Islands (49{sup o}S, 70{sup o}E) contain freshwater ecosystems among the most isolated in the world. Concentrations of polychlorinated biphenyls (PCBs) were assessed in the muscle of 48 brook trout and 38 brown trout caught during summer and spring 2006 in the rivers, lakes and ponds of Kerguelen. The sum of 29 PCBs averaged 404 and 358 ng g{sup -1} lipid, and dioxin-like PCB was 19 and 69 ng g{sup -1} lipid, in brook and brown trout, respectively. The values showed a high variability and some fish accumulated PCBs at levels similar to those of fish from impacted areas. While inter-sex differences were limited, the season and the morphotype appeared to have the most influence. Fish captured in summer had muscle PCB concentrations about three times higher than those caught in spring and the 'river' morphotype of brook trout showed the highest PCB levels. - Highlights: > First assessment of PCB contamination of biota in Kerguelen Islands, Sub-Antarctica. > PCB bioaccumulation level in trout varies from very high to undetectable. > Habitat and morphotype are the most influential factors on the variability. > Distribution pattern of PCBs in the muscle of fish is morphotype dependent. - Salmonids in hydrosystems of the Kerguelen Islands (Southern Ocean) show a high PCB bioaccumulation.

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

    Science.gov (United States)

    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.

  10. Effects of quercetin on polychlorinated biphenyls-induced liver injury in rats

    Directory of Open Access Journals (Sweden)

    Cléia Rocha de Oliveira

    2014-05-01

    Full Text Available Introduction: Polychlorinated biphenyls (PCBs, used as pesticides in agriculture, can lead to irreversible injuries in living organisms, particularly in liver. Oxidative stress has been implicated in the liver pathogenesis induced by different molecules, including PCBs. It has been demonstrated that quercetin, an antioxidant flavonoid found in the diet, exhibits a potent antioxidant effect in different liver pathologies. Objective: To evaluate oxidative stress caused by PCBs in liver and the antioxidant activity of quercetin. Methodology: We used male Wistar rats (n = 36, divided in 4 groups: control, quercetin (50 mg/kg/day, PCBs (0.4 ml/kg/day, and rats treated with both PCBs and quercetin. On day 25 blood was collected to assess liver integrity (enzymes AST, ALT and ALP, and liver samples to measure oxidative stress (TBARS, activity of antioxidant enzymes (SOD, CAT, GPx and DNA damage (micronucleus assay, and histological damage. Results: TBARS concentration and SOD activity were significantly higher in PCBs animals as compared to the PCB group receiving quercetin. CAT and GPx decreased in PCBs and increased when quercetin was added. The histological analysis showed damage to hepatocytes in PCBs, but quercetin was able to afford protection against such damage. The micronucleus test showed there was an increase in the production of microclenucleus compared to control, and quercetin was able to reduce this effect. Conclusion: Contamination with PCBs led to increased lipid peroxidation and DNA damage, and the use of antioxidant quercetin was effective in reducing PCBs-induced liver injury.

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

    Science.gov (United States)

    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 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 (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.

  12. An alternative clean-up column for the determination of polychlorinated biphenyls in solid matrices.

    Science.gov (United States)

    Ndunda, Elizabeth N; Madadi, Vincent O; Mizaikoff, Boris

    2015-12-01

    The need for continuous monitoring of polychlorinated biphenyls (PCBs) has necessitated the development of analytical techniques that are sensitive and selective with minimal reagent requirement. In light of this, we developed a column for clean-up of soil and sediment extracts, which is less demanding in terms of the amount of solvent and sorbent. The dual-layer column consists of acidified silica gel and molecularly imprinted polymers (MIPs). MIPs were synthesized via aqueous suspension polymerization using PCB 15 as the dummy template, 4-vinylpyridine as the functional monomer and ethylene glycol dimethacrylate as the cross-linker and the obtained particles characterized via SEM, BET, and batch rebinding assays. Pre-concentration of the spiked real-world water sample using MISPE gave recoveries between 85.2 and 104.4% (RSD clean-up of extracts from complex matrices provided recoveries of 91.6-102.5% (RSD clean-up using acidified silica (70.4-90.5%; RSD clean-up procedure for continuous monitoring of PCBs. Method detection limits were 0.01-0.08 ng g(-1) and 0.002-0.01 ng mL(-1) for solid matrices and water, respectively.

  13. Estrogenic activity of polychlorinated biphenyls present in human tissue and the environment.

    Science.gov (United States)

    DeCastro, B Rey; Korrick, Susan A; Spengler, John D; Soto, Ana M

    2006-04-15

    This study evaluated the estrogenicity of polychlorinated biphenyls (PCBs) present in environmental media and human tissue and assessed exposure pathways for PCB-derived estrogenic potency in air, soil, and dust from New Bedford, MA, an area with a PCB-contaminated Superfund site. Thirty-four PCB congeners were assayed for estrogenic potency using E-SCREEN, an assay based on the estrogen-dependent proliferation of MCF-7 cells in vitro. Childhood exposure to estradiol-equivalents via PCBs in environmental media was estimated byweighting previously reported New Bedford congener-specific concentrations by their relative estrogenic potency and published inhalation and soil ingestion rates. Thirteen congeners were weakly estrogenic in E-SCREEN: PCBs 17, 18, 30, 44, 49, 66, 74, 82, 99, 103, 110, 128, and 179. These PCBs were typically 6 orders of magnitude less potent than 17beta-estradiol, with proliferative potencies ranging from 0.0007% to 0.0040%. Of the environmental media assessed, air (inhalation) had the highest PCB-derived estradiol-equivalent exposure. PCB estrogenic potency information from this study provides an important resource both for preliminary estimation of routes of human exposure to xenoestrogens and for application to human health studies focused on estrogen-responsive health outcomes, such as reproductive development and related malignancies.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  16. Organochlorines and polychlorinated biphenyl environmental pollution in south coast of Rio De Janeiro state.

    Science.gov (United States)

    da Silva, Ana Maria Ferreira; Pavesi, Thelma; Rosa, Ana Cristina Simões; Santos, Tatyane Pereira Dos; de Medeiros Tabalipa, Marianne; Lemes, Vera Regina Rossi; Alves, Sergio Rabello; de Novaes Sarcinelli, Paula

    2016-07-15

    The objective of this study was to evaluate the burden of environmental pollution by Polychlorinated Biphenyls (PCBs) and Organochlorine Pesticides (OCs) in two localities of Rio de Janeiro coast, through the determination of these levels in specimens of mullets and croakers collected from May to August 2008, at Guanabara Bay (GB) and from Araújo Island (AI), at Paraty Bay. Twenty three organochlorine pollutants were detected in croakers at GB and twenty in mullets and all PCBs congeners investigated in the study were present in the two species. Ratio ∑DDT/∑PCB of 1.4 shows an important contribution of agricultural residues in GB and p,p'-DDE/∑DDT of 0.1 demonstrates a reintroduction of DDT. Consumption of mullet may represent a risk to the health of fishermen families from GB, with average and maximum estimated daily intake of ∑DDT of 9.012μg/kg p.c. and 26,174μg/kg p.c., representing 45% and 131% of ADI established by WHO.

  17. Immunotoxicology: environmental contamination by polybrominated biphenyls and immune dysfunction among residents of the State of Michigan

    Energy Technology Data Exchange (ETDEWEB)

    Bekesi, J.G.; Roboz, J.P.; Fischbein, A.; Mason, P.

    1987-01-01

    In 1973, inadvertent contamination occurred in a special farm feed supplement for lactating cows. Polybrominated biphenyls (PBBs) were used in place of magnesium oxide resulting in serious harm to farm animals, including cattle, chickens, geese, ducks. Farm families, accustomed to eating their own products, were most heavily exposed. To study the impact of PBBs, 336 adult Michigan farm residents, 117 general consumers for comparison, 75 dairy farm residents in Wisconsin, who had not eaten PBB-contaminated food, were examined, as were 79 healthy subjects in New York City. Abnormalities in the Michigan groups included hypergammaglobulinemia, exaggerated hypersensitive response to streptococci, significant decrease in absolute numbers and percentage of T and B-lymphocytes, and increased number of lymphocytes with no detectable surface markers (''null cells''). Significant reduction of in vitro immune function was noted in 20-25% of the Michigan farm residents who had eaten food containing PBB. The decreased immune function detected among the PBB-exposed farm residents tended to affect families as a unit and was independent of exposed individuals' age or sex, pointing against the possibility of genetic predisposition.

  18. Dermatological findings in capacitor manufacturing workers exposed to dielectric fluids containing polychlorinated biphenyls (PCBs)

    Energy Technology Data Exchange (ETDEWEB)

    Fischbein, A.; Wolff, M.S.; Bernstein, J.; Selikoff, I.J.; Thornton, J.

    1982-03-01

    Significant occupational exposure to polychlorinated biphenyls (PCBs) may occur in the manufacturing of capacitors and transformers, in which PCBs are used as electrical insulators. Reports of adverse health effects resulting from PCB exposure have come primarily from an incident resulting from the accidental ingestion of contaminated rice oil in Japan in 1968 (''Yusho''). Dermatological findings were prominent features and included pigmentation disturbances and chloracne. To evaluate the dermatological effects of long-term occupational exposure to PCBs, a cross-section clinical survey was conducted of 326 capacitor manufacturing workers. A high prevalence (37%) of dermatological abnormalities was found, but typical PCB-associated signs, such as chloracne, were less frequent than among patients with ''Yusho,'' despite high concentrations of plasma PCB. An association between dermatological signs and plasma levels of higher homologues of PCBs was suggested, but contaminants which have been reported to be present in commercial PCB mixtures (polychlorinated dibenzofurans) should be considered an etiologic factor or co-factor in the development of ''PCB-associated'' dermatological findings.

  19. Human exposure to polychlorinated biphenyls at toxic waste sites: investigations in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Stehr-Green, P.A.; Welty, E.; Burse, V.W.

    1988-11-01

    Beginning in 1982, environmental and population data were evaluated from waste sites contaminated with polychlorinated biphenyls (PCBs). Pilot exposure assessment studies were conducted at 12 sites where risks of human exposure were thought to be greatest. Serum PCB levels in persons at highest risk of nonoccupationally related exposures (because of their self-reported frequencies and types of activities in contaminated areas) at 10 sites were within background ranges, even though environmental contamination levels as high as 2.5 parts per billion (ppb) in monitoring well water samples and 330,000 ppb in soil samples were measured. At the 2 remaining sites, elevated serum levels were found in these high-risk persons, which require further evaluation by community surveys. These results illustrate that, despite elevated environmental contaminant levels, unless uptake of chemicals above background exposure levels can be demonstrated, adverse health effects cannot be attributed to waste site chemicals. However, health risks due to background exposure levels, as well as in populations with elevated PCB body burdens need further study.

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

    Science.gov (United States)

    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).

  1. Determination of phenolic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Chao, G.K.J.; Suatoni, J.C.

    1982-01-01

    Details are given of a procedure for separation and identification of phenolic compounds in aqueous solution by high-performance liquid chromatography. It can also be applied to non-aqueous samples after preliminary isolation of a polar fraction containing the phenolic compounds.

  2. NATURAL POLYACETYLENE COMPOUNDS

    Directory of Open Access Journals (Sweden)

    D. A. Konovalov

    2014-01-01

    Full Text Available Polyacetylenes (polyynes are compounds which contain two or more triple bonds in its structure. About 2 000 different polyacetylenes and biogenetically related substances were identified in 24 families of higher plants. However, most of these compounds were found in seven families of flowering plants: Apiaceae (Umbelliferae, Araliaceae, Asteraceae (Compositae, Campanulaceae, Olacaceae, Pittosporaceae and Santalaceae. Polyacetylenes are relatively unstable, chemically and biologically active compounds, and present in fungi, microorganisms, marine invertebrates and other organisms except for plants. Acetylenes form distinct specialized group of chemically active natural compounds, which are biosynthesized in plants of unsaturated fatty acids. In addition to widespread aliphatic polyacetylenes thiophenes dithiacyclohexadienes (thiarubrines, thioethers, sulphoxides, sulphones, alkamides, chlorohydrins, lactones, spiroacetal enol ethers, furans, pyrans, tetrahydropyrans, isocoumarins, aromatic acetylenes were also found in plant species. Polyacetylenes are localized in different plant organs, and can be found both individually and as a compound with carbohydrates, terpene, phenolic and other compounds. Many polyacetylenes are found in the composition of the essential oils of plants and it confirms their strongly marked ecological functions. From biological point of view these compounds are often synthesized by plants as toxic or bitter antifeedants, allelopathic compounds, phytoalexins or broadly antibiotic components. Polyynes are strong photosensitizers. They exhibit anti-inflammatory, anti-coagulant, anti-bacterial, antituberculosis, anti-fungal, anti-viral, neuroprotective and neurotoxic activity. Immunostimulatory influence associated with certain allergenicity of some of these substances was established. Therefore, without a doubt polyacetylenes are of interest for the modern pharmacy and medicine.

  3. Atropisomerism: the effect of the axial chirality in bioactive compounds; Atropoisomerismo: o efeito da quiralidade axial em substancias bioativas

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Anderson Rouge dos; Pinheiro, Alessandra Campbell; Sodero, Ana Carolina Renno; Cunha, Andrea Sousa da; Padilha, Monica Costa; Sousa, Priscila Mesquita de; Fontes, Silvia Paredes [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Quimica. Dept. de Quimica Organica; Veloso, Marcia Paranho [Universidade Federal de Alfenas, MG (Brazil); Fraga, Carlos Alberto Manssour [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Faculdade de Farmacia. Lab. de Avaliacao e Sintese de Substancias Bioativas (LASSBio)]. E-mail: cmfraga@pharma.ufrj.br

    2007-01-15

    Atropisomerism is a special kind of stereoisomeric relationship that arises from the freezing of a certain conformation of an organic molecule, associated with a high rotational barrier about a single covalent bond. Atropisomerism has been originally described in orto-functionalized biphenyl derivatives, but a lot of other organic functionalities can present this structural phenomenon, characterized by the presence of chiral properties in compounds that do not present classical stereogenic centers. Atropisomeric compounds, intermediates and catalysts have well-know importance in organic synthesis, but the influence of the axial chirality in substances able to modulate biological systems is still not very exploited in drug design and development. In this context, the present account describes the importance of this structural property in the medicinal chemistry of different classes of bioactive compounds or therapeutic agents, emphasizing how atropisomerism could affect the molecular recognition of a ligand or a prototype by the target bioreceptor. (author)

  4. High performance solid-phase extraction cleanup method coupled with gas chromatography-triple quadrupole mass spectrometry for analysis of polychlorinated naphthalenes and dioxin-like polychlorinated biphenyls in complex samples.

    Science.gov (United States)

    Li, Fang; Jin, Jing; Tan, Dongqin; Xu, Jiazhi; Dhanjai; Ni, Yuwen; Zhang, Haijun; Chen, Jiping

    2016-05-27

    A solid-phase extraction (SPE) cleanup method was developed to purify the sample extracts for the analysis of polychlorinated naphthalenes (PCNs) and dioxin-like polychlorinated biphenyls (dl-PCBs). Monodisperse magnesium oxide (MgO) microspheres and basic alumina were used as SPE adsorbents. Important parameters of the SPE procedure were optimized, including the amount of basic alumina and the type and volume of the washing and elution solvents. The optimized SPE cleanup method exhibited excellent purification performance for the removal of organochlorinated compounds, lipid compounds, sulfur, and pigments. Additionally, it was found that the retention activities of congeners differed with the number and position of the chlorine substituents in PCNs. In this study, an analytical method based on a combination of accelerated solvent extraction (ASE) coupled with SPE cleanup and gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS) is proposed for the analysis of PCNs and dl-PCBs in complex samples (sediment, pine needle, and scallop samples). The analytical method demonstrates good linearity, acceptable recovery (63-148%) and precision (relative standard deviations less than 26%). The limits of detection (LODs) of PCN and dl-PCB congeners were in the range of 0.6-19.1pgg(-1) and 0.4-8.6pgg(-1), respectively. The PCNs and dl-PCBs levels in these samples ranged from 0.16 to 3.07ngg(-1) dry weight (dw) and from undetectable to 0.07ngg(-1) dw, respectively.

  5. Polychlorinated biphenyls and polybrominated biphenyl ethers in adipose tissue and matched serum from an E-waste recycling area (Wenling, China).

    Science.gov (United States)

    Lv, Quan-Xia; Wang, Wenyue; Li, Xing-Hong; Yu, Lianlian; Zhang, Yun; Tian, Yuan

    2015-04-01

    To Date, the knowledge on relationship between PCBs/PBDEs exposure and thyroid hormones (THs) levels during pregnancy still needs to be extended. Meanwhile, studies on congener-specific adipose-serum ratios for PCBs/PBDEs were limited. This study reports the levels of PCBs/PBDEs in serum-adipose tissue samples (n = 64) from expectant women living surrounding e-waste recycling sites in Wenling, China. Their concentrations varied from several to hundreds of ng g(-1) lipid. Maternal exposure to PCBs was associated with lower TSH during pregnancy, suggesting possible implication for maternal health and fetal development. The compound levels between the adipose tissue and matched serum samples were highly correlated (p < 0.001), generating a predicted adipose-serum partitioning relationship for individual PCB congener and PBDE congener. Molecular characteristics, such as Kow value, molecular weight and molecular volume, may play a key role in the variable partitioning of some compounds between serum and adipose tissue.

  6. Thermal and Cure Kinetics of Epoxy Molding Compounds Cured with Thermal Latency Accelerators

    Directory of Open Access Journals (Sweden)

    Chean-Cheng Su

    2013-01-01

    Full Text Available The cure kinetics and mechanisms of a biphenyl type epoxy molding compounds (EMCs with thermal latency organophosphine accelerators were studied using differential scanning calorimetry (DSC. Although the use of triphenylphosphine-1,4-benzoquinone (TPP-BQ and triphenylphosphine (TPP catalysts in biphenyl type EMCs exhibited autocatalytic mechanisms, thermal latency was higher in the TPP-BQ catalyst in EMCs than in the TPP catalyst in EMCs. Analyses of thermal characteristics indicated that TPP-BQ is inactive at low temperatures. At high temperatures, however, TPP-BQ increases the curing rate of EMC in dynamic and isothermal curing experiments. The reaction of EMCs with the TPP-BQ latent catalyst also had a higher temperature sensitivity compared to the reaction of EMCs with TPP catalyst. In resin transfer molding, EMCs containing the TPP-BQ thermal latency accelerator are least active at a low temperature. Consequently, EMCs have a low melt viscosity before gelation, and the resins and filler are evenly mixed in the kneading process. Additionally, flowability is increased before the EMCs form a network structure in the molding process. The proposed kinetic model adequately describes curing behavior in EMCs cured with two different organophosphine catalysts up to the rubber state in the progress of curing.

  7. Heart testing compound

    Science.gov (United States)

    Knapp, F.F. Jr.; Goodman, M.M.

    1983-06-29

    The compound 15-(p-(/sup 125/I)-iodophenyl)-6-tellurapentadecanoic acid is disclosed as a myocardial imaging agent having rapid and pronounced uptake, prolonged myocardial retention, and low in vivo deiodination.

  8. Compound Semiconductor Radiation Detectors

    CERN Document Server

    Owens, Alan

    2012-01-01

    Although elemental semiconductors such as silicon and germanium are standard for energy dispersive spectroscopy in the laboratory, their use for an increasing range of applications is becoming marginalized by their physical limitations, namely the need for ancillary cooling, their modest stopping powers, and radiation intolerance. Compound semiconductors, on the other hand, encompass such a wide range of physical and electronic properties that they have become viable competitors in a number of applications. Compound Semiconductor Radiation Detectors is a consolidated source of information on all aspects of the use of compound semiconductors for radiation detection and measurement. Serious Competitors to Germanium and Silicon Radiation Detectors Wide-gap compound semiconductors offer the ability to operate in a range of hostile thermal and radiation environments while still maintaining sub-keV spectral resolution at X-ray wavelengths. Narrow-gap materials offer the potential of exceeding the spectral resolutio...

  9. Compound composite odontoma.

    Science.gov (United States)

    Girish, G; Bavle, Radhika M; Singh, Manish Kumar; Prasad, Sahana N

    2016-01-01

    The term odontoma has been used as a descriptor for any tumor of odontogenic origin. It is a growth in which both epithelial and mesenchymal cells exhibits complete differentiation. Odontomas are considered as hamartomas rather than true neoplasm. They are usually discovered on routine radiographic examination. Odontomas, according to the World Health Organization, are classified into complex odontoma and compound odontomas. The present paper reports a case of compound composite odontomas.

  10. Compound composite odontoma

    Directory of Open Access Journals (Sweden)

    G Girish

    2016-01-01

    Full Text Available The term odontoma has been used as a descriptor for any tumor of odontogenic origin. It is a growth in which both epithelial and mesenchymal cells exhibits complete differentiation. Odontomas are considered as hamartomas rather than true neoplasm. They are usually discovered on routine radiographic examination. Odontomas, according to the World Health Organization, are classified into complex odontoma and compound odontomas. The present paper reports a case of compound composite odontomas.

  11. Chemistry of peroxide compounds

    Science.gov (United States)

    Volnov, I. I.

    1981-01-01

    The history of Soviet research from 1866 to 1967 on peroxide compounds is reviewed. This research dealt mainly with peroxide kinetics, reactivity and characteristics, peroxide production processes, and more recently with superoxides and ozonides and emphasis on the higher oxides of group 1 and 2 elements. Solid state fluidized bed synthesis and production of high purity products based on the relative solubilities of the initial, intermediate, and final compounds and elements in liquid ammonia are discussed.

  12. Historical reconstruction of polychlorinated biphenyl (PCB) exposures for workers in a capacitor manufacturing plant.

    Science.gov (United States)

    Hopf, Nancy B; Ruder, Avima M; Waters, Martha A

    2014-05-01

    We developed a semiquantitative job exposure matrix (JEM) for workers exposed to polychlorinated biphenyls (PCBs) at a capacitor manufacturing plant from 1946 to 1977. In a recently updated mortality study, mortality of prostate and stomach cancer increased with increasing levels of cumulative exposure estimated with this JEM (trend p values = 0.003 and 0.04, respectively). Capacitor manufacturing began with winding bales of foil and paper film, which were placed in a metal capacitor box (pre-assembly), and placed in a vacuum chamber for flood-filling (impregnation) with dielectric fluid (PCBs). Capacitors dripping with PCB residues were then transported to sealing stations where ports were soldered shut before degreasing, leak testing, and painting. Using a systematic approach, all 509 unique jobs identified in the work histories were rated by predetermined process- and plant-specific exposure determinants; then categorized based on the jobs' similarities (combination of exposure determinants) into 35 job exposure categories. The job exposure categories were ranked followed by a qualitative PCB exposure rating (baseline, low, medium, and high) for inhalation and dermal intensity. Category differences in other chemical exposures (solvents, etc.) prevented further combining of categories. The mean of all available PCB concentrations (1975 and 1977) for jobs within each intensity rating was regarded as a representative value for that intensity level. Inhalation (in microgram per cubic milligram) and dermal (unitless) exposures were regarded as equally important. Intensity was frequency adjusted for jobs with continuous or intermittent PCB exposures. Era-modifying factors were applied to the earlier time periods (1946-1974) because exposures were considered to have been greater than in later eras (1975-1977). Such interpolations, extrapolations, and modifying factors may introduce non-differential misclassification; however, we do believe our rigorous method

  13. Corticosterone stress response in tree swallows nesting near polychlorinated biphenyl- and dioxin-contaminated rivers

    Science.gov (United States)

    Franceschini, M.D.; Custer, Christine M.; Custer, T.W.; Reed, J.M.; Romero, L.M.

    2008-01-01

    We assayed baseline and stress-induced corticosterone concentrations from adult female and nestling tree swallows, Tachycineta bicolor, from New England, USA, sites with different levels of contamination with polychlorinated biphenyls (PCBs) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Corticosterone was compared over 2 years from a highly contaminated PCB site along the Housatonic River (Berkshire County, MA, USA), a midrange contaminated site upstream, and a reference site. Adult females (n = 29), sampled only in 2003, showed an inverted-U association with PCBs, with higher stress-induced corticosterone with midrange contamination than at the high-contamination site. In nestlings, stress-induced corticosterone was highest for the highly contaminated site compared with the other sites in 2003 (n = 53, 29 nests), with no difference among sites in 2004 (n = 93, 27 nests). In 2004, we began testing mechanisms underlying these changes in nestlings at the high- and low-PCB sites. Corticosterone response to dexamethasone injection (used to test negative feedback) was not different between sites, but stress-induced corticosterone was reduced at the contaminated site after adrenocorticotropin hormone injection (used to test adrenal responsiveness), suggesting an inhibited ability to mount a stress response. We also compared nestlings from a stretch of the Woonasquatucket River, Rhode Island, USA, heavily contaminated with TCDD (n = 80, 43 nests) with nestlings from an upstream site that had lower levels of TCDD and the Berkshire County reference site. Although there were no stress-induced differences, baseline corticosterone was lower at the higher TCDD site than at the reference site. Altogether these findings suggest that tree swallows chronically exposed to high PCB and TCDD levels exhibit altered baseline and stress-induced corticosterone responses, but the patterns of alteration might not be predictable. ?? 2008 SETAC.

  14. Mammalian Cytochrome P450-Dependent Metabolism of Polychlorinated Dibenzo-p-dioxins and Coplanar Polychlorinated Biphenyls

    Directory of Open Access Journals (Sweden)

    Hideyuki Inui

    2014-08-01

    Full Text Available Polychlorinated dibenzo-p-dioxins (PCDDs and coplanar polychlorinated biphenyls (PCBs contribute to dioxin toxicity in humans and wildlife after bioaccumulation through the food chain from the environment. The authors examined human and rat cytochrome P450 (CYP-dependent metabolism of PCDDs and PCBs. A number of human CYP isoforms belonging to the CYP1 and CYP2 families showed remarkable activities toward low-chlorinated PCDDs. In particular, human CYP1A1, CYP1A2, and CYP1B1 showed high activities toward monoCDDs, diCDDs, and triCDDs but no detectable activity toward 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-tetraCDD. Large amino acids located at putative substrate-recognition sites and the F-G loop in rat CYP1A1 contributed to the successful metabolism of 2,3,7,8-tetraCDD. Rat, but not human, CYP1A1 metabolized 3,3',4,4',5-pentachlorobiphenyl (CB126 to two hydroxylated metabolites. These metabolites are probably less toxic than is CB126, due to their higher solubility. Homology models of human and rat CYP1A1s and CB126 docking studies indicated that two amino acid differences in the CB126-binding cavity were important for CB126 metabolism. In this review, the importance of CYPs in the metabolism of dioxins and PCBs in mammals and the species-based differences between humans and rats are described. In addition, the authors reveal the molecular mechanism behind the binding modes of dioxins and PCBs in the heme pocket of CYPs.

  15. Impact of polychlorinated biphenyls contamination on estrogenic activity in human male serum.

    Science.gov (United States)

    Plísková, Martina; Vondrácek, Jan; Canton, Rocio Fernandez; Nera, Jirí; Kocan, Anton; Petrík, Ján; Trnovec, Tomás; Sanderson, Thomas; van den Berg, Martin; Machala, Miroslav

    2005-10-01

    Polychlorinated biphenyls (PCBs) are thought to cause numerous adverse health effects, but their impact on estrogen signaling is still not fully understood. In the present study, we used the ER-CALUX bioassay to determine estrogenic/antiestrogenic activities of the prevalent PCB congeners and PCB mixtures isolated from human male serum. The samples were collected from residents of an area with an extensive environmental contamination from a former PCB production site as well as from a neighboring background region in eastern Slovakia. We found that the lower-chlorinated PCBs were estrogenic, whereas the prevalent higher-chlorinated PCB congeners 138, 153, 170, 180, 187, 194, 199, and 203, as well as major PCB metabolites, behaved as antiestrogens. Coplanar PCBs had no direct effect on estrogen receptor (ER) activation in this in vitro model. In human male serum samples, high levels of PCBs were associated with a decreased ER-mediated activity and an increased dioxin-like activity, as determined by the DR-CALUX assay. 17beta-Estradiol (E2) was responsible for a major part of estrogenic activity identified in total serum extracts. Significant negative correlations were found between dioxin-like activity, as well as mRNA levels of cytochromes P450 1A1 and 1B1 in lymphocytes, and total estrogenic activity. For sample fractions containing only persistent organic pollutants (POPs), the increased frequency of antiestrogenic samples was associated with a higher sum of PCBs. This suggests that the prevalent non-dioxin-like PCBs were responsible for the weak antiestrogenic activity of some POPs fractions. Our data also suggest that it might be important to pay attention to direct effects of PCBs on steroid hormone levels in heavily exposed subjects.

  16. Polychlorinated biphenyl serum levels in subjects with hepatocellular carcinoma as compared with the general population

    Directory of Open Access Journals (Sweden)

    Claudia Zani

    2014-11-01

    Full Text Available Background. Polychlorinated biphenyls (PCBs have been recognized as human carcinogens and cause liver cancer in animal experimental studies. However, no study investigated their association with hepatocellular carcinoma (HCC so far.  This study aimed to evaluate the serum PCB concentration in HCC patients and in healthy subjects of the general population living in Brescia, North Italy, a highly industrialized area with heavy PCB environmental pollution due to the presence of a PCB producing factory. Methods. Lipid-adjusted PCB concentrations, computed as the sum of 24 congeners, were measured in the serum of 101 HCC patients and in 101 healthy subjects of the same age and gender.Results. Hepatitis B and C virus infection and history of heavy alcohol intake were found, alone and combined, in 87% of HCC patients. No difference was found in PCB serum concentration of HCC patients with and without, and according to, the major risk factors for liver disease. No significant difference was observed in serum total PCB concentration between HCC patients (median: 1081; range: 287.0-3182.0 ng/g lipid and healthy subjects (median: 1199.3; range: 225.7-22825 ng/g lipid. PCB congeners 118, 138, 153, 156, 180 and 194 were the only ones found over the detection limit in at least 30% of HCC patients. The serum level of PCB 118, but not that of other congeners, was higher in HCC patients than in healthy subjects.Conclusion. These findings  do not support the hypothesis that PCBs play an important role in HCC development, although a contribution by some specific congeners cannot be ruled out. 

  17. Environmental life-cycle comparisons of two polychlorinated biphenyl remediation technologies: incineration and base catalyzed decomposition.

    Science.gov (United States)

    Hu, Xintao; Zhu, Jianxin; Ding, Qiong

    2011-07-15

    Remediation action is critical for the management of polychlorinated biphenyl (PCB) contaminated sites. Dozens of remediation technologies developed internationally could be divided in two general categories incineration and non-incineration. In this paper, life cycle assessment (LCA) was carried out to study the environmental impacts of these two kinds of remediation technologies in selected PCB contaminated sites, where Infrared High Temperature Incineration (IHTI) and Base Catalyzed Decomposition (BCD) were selected as representatives of incineration and non-incineration. A combined midpoint/damage approach was adopted by using SimaPro 7.2 and IMPACTA2002+ to assess the human toxicity, ecotoxicity, climate change impact, and resource consumption from the five subsystems of IHTI and BCD technologies, respectively. It was found that the major environmental impacts through the whole lifecycle arose from energy consumption in both IHTI and BCD processes. For IHTI, primary and secondary combustion subsystem contributes more than 50% of midpoint impacts concerning with carcinogens, respiratory inorganics, respiratory organics, terrestrial ecotoxity, terrestrial acidification/eutrophication and global warming. In BCD process, the rotary kiln reactor subsystem presents the highest contribution to almost all the midpoint impacts including global warming, non-renewable energy, non-carcinogens, terrestrial ecotoxity and respiratory inorganics. In the view of midpoint impacts, the characterization values for global warming from IHTI and BCD were about 432.35 and 38.5 kg CO(2)-eq per ton PCB-containing soils, respectively. LCA results showed that the single score of BCD environmental impact was 1468.97 Pt while IHTI's score is 2785.15 Pt, which indicates BCD potentially has a lower environmental impact than IHTI technology in the PCB contaminated soil remediation process.

  18. Neurodevelopmental toxicity of prenatal polychlorinated biphenyls (PCBs by chemical structure and activity: a birth cohort study

    Directory of Open Access Journals (Sweden)

    Park Hye-Youn

    2010-08-01

    Full Text Available Abstract Background Polychlorinated biphenyls (PCBs are ubiquitous environmental toxins. Although there is growing evidence to support an association between PCBs and deficits of neurodevelopment, the specific mechanisms are not well understood. The potentially different roles of specific PCB groups defined by chemical structures or hormonal activities e.g., dioxin-like, non-dioxin like, or anti-estrogenic PCBs, remain unclear. Our objective was to examine the association between prenatal exposure to defined subsets of PCBs and neurodevelopment in a cohort of infants in eastern Slovakia enrolled at birth in 2002-2004. Methods Maternal and cord serum samples were collected at delivery, and analyzed for PCBs using high-resolution gas chromatography. The Bayley Scales of Infant Development -II (BSID were administered at 16 months of age to over 750 children who also had prenatal PCB measurements. Results Based on final multivariate-adjusted linear regression model, maternal mono-ortho-substituted PCBs were significantly associated with lower scores on both the psychomotor (PDI and mental development indices (MDI. Also a significant association between cord mono-ortho-substituted PCBs and reduced PDI was observed, but the association with MDI was marginal (p = 0.05. Anti-estrogenic and di-ortho-substituted PCBs did not show any statistically significant association with cognitive scores, but a suggestive association between di-ortho-substituted PCBs measured in cord serum and poorer PDI was observed. Conclusion Children with higher prenatal mono-ortho-substituted PCB exposures performed more poorly on the Bayley Scales. Evidence from this and other studies suggests that prenatal dioxin-like PCB exposure, including mono-ortho congeners, may interfere with brain development in utero. Non-dioxin-like di-ortho-substituted PCBs require further investigation.

  19. Organochlorine pesticides, polychlorinated biphenyls, and polybrominated diphenyl ethers in Irrawaddy dolphins from India.

    Science.gov (United States)

    Kannan, K; Ramu, K; Kajiwara, N; Sinha, R K; Tanabe, S

    2005-10-01

    The Irrawaddy dolphin (Orcaella brevirostris) is at risk of extinction throughout its range as a result of incidental catches, habitat degradation, and pollution. Populations of Irrawaddy dolphins are constrained by the species' narrow habitat requirement-lagoons, estuaries, rivers, and lakes-and are therefore particularly vulnerable to the effects of human activities. In this study, for the first time, concentrations of organochlorine (OC) pesticides, polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) were determined in tissues of Irrawaddy dolphins collected from Chilika Lake, India, to understand the status of contamination. Dichlorodiphenyltrichloroethane and its metabolites (DDTs) were the predominant contaminants found in Irrawaddy dolphins; the highest concentration found was 10,000 ng/g lipid weight in blubber. Hexachlorocyclohexanes (HCHs) were the second most prevalent contaminants in dolphin tissues. Concentrations of PCBs, chlordanes, hexachlorobenzene, tris(4-chlorophenyl)methane, and tris(4-chlorophenyl)methanol were in the ranges of few ng/g to few hundreds of ng/g on a lipid-weight basis. In general, concentrations of OC pesticides and PCBs in Irrawaddy dolphins were lower than the concentrations reported for coastal and riverine dolphins collected in Asia. PBDEs were detected in the blubber of Irrawaddy dolphins at concentrations ranging from 0.98 to 18 ng/g lipid weight. BDE congener 47 accounted for 60% to 75% of the total PBDE concentrations. Although these results establish the baseline levels of persistent organic pollutants in Irrawaddy dolphins, efforts should be made to decrease the sources of contamination by DDTs and HCHs in Chilika Lake.

  20. Polychlorinated biphenyls and pesticides in surficial coastal sediments of the Ligurian Sea

    Energy Technology Data Exchange (ETDEWEB)

    Bertolotto, R.M.; Cuneo, C.; Albanese, S. [ARPAL, Direzione Scientifica, Genova (Italy); Magherini, A. [ARPAL, Dipartimento di Genova, Genova (Italy); Frignani, M.; Bellucci, L.G.; Alvarado-Aguilar, D. [ISMAR, Sezione di Geologia Marina, Bologna (Italy)

    2004-09-15

    Polychlorinated biphenyls (PCBs) and chlorinated pesticides, such as DDT and its analogues, are organic contaminants widespread throughout the terrestrial and oceanic environments due to their common use and their resistance to degradation. Since harmful effects have been associated to these chemicals and well documented, they are classified as priority pollutants by both the US Environmental Protection Agency (EPA) and the European Union. Because of the very low solubility in water and the tendency to adsorb onto sediment particles, the ultimate fate of both PCBs and DDTs in the marine environment is the incorporation into sediments. Hence, the concentrations of these chlorinate chemicals in bottom sediments can provide an insight on the quality of the environment and the potential threat to marine organisms and human beings. The Ligurian Sea belongs to the north part of the western Mediterranean. The coastal morphology of the Liguria Region is rather variable, and frequently cliffs drop sheer to the sea. The limited width of the coastal zone, comprised between the sea and the mountains, determined a gathering of the urban areas with a consequent concentration of both civil and industrial presence in a narrow but highly populated territory. In particular Genova, but also other cities have a long history of industrial and harbour activities, whereas long tracts of the coast are dedicated to tourism. The circulation of the Ligurian Sea is rather well known. In particular, surface and intermediate currents follow a cyclonic circulation. However local circulation is the true responsible of the dispersion of sediment material along the coast, and these alongshore currents often cause an eastward oriented transport. The Ligurian coastal zone is very developed, and hosts all sort of industrial, agricultural and tourist activities that can be sources of persistent organochlorine chemicals. Therefore, the purpose of this study was to assess concentrations, distributions

  1. Polychlorinated Biphenyl (PCB) Bioaccumulation in Fish: A Look at Michigan's Upper Peninsula

    Science.gov (United States)

    Sokol, E. C.; Urban, N. R.; Perlinger, J. A.; Khan, T.; Friedman, C. L.

    2014-12-01

    Fish consumption is an important economic, social and cultural component of Michigan's UpperPeninsula, where safe fish consumption is threatened due to polychlorinated biphenyl (PCB)contamination. Despite its predominantly rural nature, the Upper Peninsula has a history of industrialPCB use. PCB congener concentrations in fish vary 50-fold in Upper Peninsula lakes. Several factors maycontribute to this high variability including local point sources, unique watershed and lakecharacteristics, and food web structure. It was hypothesized that the variability in congener distributionscould be used to identify factors controlling concentrations in fish, and then to use those factors topredict PCB contamination in fish from lakes that had not been monitored. Watershed and lakecharacteristics were acquired from several databases for 16 lakes sampled in the State's fishcontaminant survey. Species congener distributions were compared using Principal Component Analysis(PCA) to distinguish between lakes with local vs. regional, atmospheric sources; six lakes were predictedto have local sources and half of those have confirmed local PCB use. For lakes without local PCBsources, PCA indicated that lake size was the primary factor influencing PCB concentrations. The EPA'sbioaccumulation model, BASS, was used to predict PCB contamination in lakes without local sources as afunction of food web characteristics. The model was used to evaluate the hypothesis that deep,oligotrophic lakes have longer food webs and higher PCB concentrations in top predator fish. Based onthese findings, we will develop a mechanistic watershed-lake model to predict PCB concentrations infish as a function of atmospheric PCB concentrations, lake size, and trophic state. Future atmosphericconcentrations, predicted by modeling potential primary and secondary emission scenarios, will be usedto predict the time horizon for safe fish consumption.

  2. Miniaturized selective pressurized liquid extraction of polychlorinated biphenyls and polybrominated diphenyl ethers from feedstuffs.

    Science.gov (United States)

    Pena-Abaurrea, M; Ramos, J J; Gonzalez, M J; Ramos, L

    2013-01-18

    A new miniaturized pressurized liquid extraction (PLE) with in-cell purification method has been developed for the simultaneous extraction of endogenous prioritary and toxic polychlorinated biphenyls (PCBs) and environmentally relevant tri- to deca-brominated diphenyl ether (PBDE) congeners from different feed matrices. Parameters affecting the efficiency of the selective PLE process, such as sorbent:matrix ratio, volume and nature of the extraction solvent, PLE working mode, extraction time and temperature, and amount of co-sorbents, were optimized. n-Hexane and n-hexane:dichloromethane (1:1, v/v) were used as extraction solvents. 8-mL of organic solvents and 3.5 g of sorbents sufficed for complete sample treatment. Only 0.25 g of feed sample were required for accurate determination of the endogenous PCBs studied using gas chromatography with a micro-electron capture detector (GC-μECD) during method development, and for PBDE analysis using either GC-μECD or gas chromatography with negative chemical ionization-quadrupole mass spectrometry (GC-NCI-qMS). Gas chromatography coupled to ion trap detection working in tandem mode, GC-ITD (MS/MS), was used for final PCB confirmation. Additional purification of the sample extracts was not required. The performance of the complete PLE-based method was evaluated at two spiking levels, 0.4 and 4 ng/g wet weight. Recoveries in the range 60-120% were obtained for PCBs, while those of PBDEs ranged from 86% to 114% for most of the target analytes. The relative standard deviations were in general lower than 20%. The optimized procedure was applied to the determination of the investigated PCBs and PBDEs in a variety of feed samples.

  3. Biphenyl liquid crystalline epoxy resin as a low-shrinkage resin-based dental restorative nanocomposite.

    Science.gov (United States)

    Hsu, Sheng-Hao; Chen, Rung-Shu; Chang, Yuan-Ling; Chen, Min-Huey; Cheng, Kuo-Chung; Su, Wei-Fang

    2012-11-01

    Low-shrinkage resin-based photocurable liquid crystalline epoxy nanocomposite has been investigated with regard to its application as a dental restoration material. The nanocomposite consists of an organic matrix and an inorganic reinforcing filler. The organic matrix is made of liquid crystalline biphenyl epoxy resin (BP), an epoxy resin consisting of cyclohexylmethyl-3,4-epoxycyclohexanecarboxylate (ECH), the photoinitiator 4-octylphenyl phenyliodonium hexafluoroantimonate and the photosensitizer champhorquinone. The inorganic filler is silica nanoparticles (∼70-100 nm). The nanoparticles were modified by an epoxy silane of γ-glycidoxypropyltrimethoxysilane to be compatible with the organic matrix and to chemically bond with the organic matrix after photo curing. By incorporating the BP liquid crystalline (LC) epoxy resin into conventional ECH epoxy resin, the nanocomposite has improved hardness, flexural modulus, water absorption and coefficient of thermal expansion. Although the incorporation of silica filler may dilute the reinforcing effect of crystalline BP, a high silica filler content (∼42 vol.%) was found to increase the physical and chemical properties of the nanocomposite due to the formation of unique microstructures. The microstructure of nanoparticle embedded layers was observed in the nanocomposite using scanning and transmission electron microscopy. This unique microstructure indicates that the crystalline BP and nanoparticles support each other and result in outstanding mechanical properties. The crystalline BP in the LC epoxy resin-based nanocomposite was partially melted during exothermic photopolymerization, and the resin expanded via an order-to-disorder transition. Thus, the post-gelation shrinkage of the LC epoxy resin-based nanocomposite is greatly reduced, ∼50.6% less than in commercialized methacrylate resin-based composites. This LC epoxy nanocomposite demonstrates good physical and chemical properties and good biocompatibility

  4. The levels of polychlorinated biphenyls in 1,4-dichlorobenzene mothballs

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Wenbin; Zheng, Minghui; Xing, Ying; Wang, Dongshen; Zhao, Xingru; Gao, Lirong [Chinese Academy of Sciences, Beijing (China). Key laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences

    2004-09-15

    The chemical 1,4-dichlorobenzene (p-DCB), also called paramoth, is one of the chemicals commonly used to make mothballs. For the more than 20 years, p-DCB has been used principally (35-55% of all uses) as a space deodorant for toilets and refuse containers, and as a fumigant for control of moths, molds, and mildews. The process of production of p-DCB currently used by industry is direct chlorination of benzene or chlorobenzene in the presence of a Friedel-Crafts catalyst (typically FeCl{sub 3}), and the pure products of p-DCB are obtained by distillation and crystallization from the mixture of polychlorinated benzenes. This process is similar to that of production of PCBs which were manufactured commercially by the progressive chlorination of biphenyl in the presence of a suitable catalyst, e.g., iron chloride. However, few studies on the formation of PCBs from chlorobenzenes have been published. Buser reported significant quantities of PCDFs and a small amount of PCDDs, PCBs, and chlorophenols were formed in the pyrolysis of chlorobenzenes at 620 C. Peng-Yan Liu et al. revealed that lower chlorinated benzenes produce more PCBs than higher ones. Nevertheless, prior to this study, no reports on PCBs in p-DCB and the restriction of PCBs in p-DCB products have been found. In this paper, the occurrence and distribution of dioxin-like PCBs and total PCBs in some commercial p-DCB mothballs are investigated. Except of the toxic of p-DCB, the low concentration of PCBs in p-DCB mothballs should not be negligible.

  5. Biodegradation of polychlorinated biphenyls (PCBs) by the novel identified cyanobacterium Anabaena PD-1.

    Science.gov (United States)

    Zhang, Hangjun; Jiang, Xiaojun; Lu, Liping; Xiao, Wenfeng

    2015-01-01

    Polychlorinated biphenyls (PCBs), a class of hazardous pollutants, are difficult to dissipate in the natural environment. In this study, a cyanobacterial strain Anabaena PD-1 showed good resistance against PCB congeners. Compared to a control group, chlorophyll a content decreased 3.7% and 11.7% when Anabaena PD-1 was exposed to 2 and 5 mg/L PCBs for 7 d. This cyanobacterial strain was capable of decomposing PCB congeners which was conclusively proved by determination of chloride ion concentrations in chlorine-free medium. After 7 d, the chloride ion concentrations in PCB-treated groups (1, 2, 5 mg/L) were 3.55, 3.05, and 2.25 mg/L, respectively. The genetic information of strain PD-1 was obtained through 16S rRNA sequencing analysis. The GenBank accession number of 16S rRNA of Anabaena PD-1 was KF201693.1. Phylogenetic tree analysis clearly indicated that Anabaena PD-1 belonged to the genus Anabaena. The degradation half-life of Aroclor 1254 by Anabaena PD-1 was 11.36 d; the total degradation rate for Aroclor 1254 was 84.4% after 25 d. Less chlorinated PCB congeners were more likely to be degraded by Anabaena PD-1 in comparison with highly chlorinated congeners. Meta- and para-chlorines in trichlorodiphenyls and tetrachlorobiphenyls were more susceptible to dechlorination than ortho-chlorines during the PCB-degradation process by Anabaena PD-1. Furthermore, Anabaena PD-1 can decompose dioxin-like PCBs. The percent biodegradation of 12 dioxin-like PCBs by strain PD-1 ranged from 37.4% to 68.4% after 25 days. Results above demonstrate that Anabaena PD-1 is a PCB-degrader with great potential for the in situ bioremediation of PCB-contaminated paddy soils.

  6. Modeling polychlorinated biphenyl mass transfer after amendment of contaminated sediment with activated carbon

    Energy Technology Data Exchange (ETDEWEB)

    David Werner; Upal Ghosh; Richard G. Luthy [University of Newcastle upon Tyne, Newcastle (United Kingdom)

    2006-07-01

    The sorption kinetics and concentration of polychlorinated biphenyls (PCBs) in historically polluted sediment is modeled to assess a remediation strategy based on in situ PCB sequestration by mixing with activated carbon (AC). The authors extend their evaluation of a model based on intraparticle diffusion by including a biomimetic semipermeable membrane device (SPMD) and a first-order degradation rate for the aqueous phase. The model predictions are compared with the previously reported experimental PCB concentrations in the bulk water phase and in SPMDs. The simulated scenarios comprise a marine and a freshwater sediment, four PCB congeners, two AC grain sizes, four doses of AC, and comparison with laboratory experiments. The modeling approach distinguishes between two different sediment particles types: a light-density fraction representing carbonaceous particles such as charcoal, coal, coke, cenospheres, or wood, and a heavy-density fraction representing the mineral phase with coatings of organic matter. A third particle type in the numerical model is AC. The model qualitatively reproduces the observed shifts in the PCB distribution during repartitioning after AC amendment but overestimates the overall effect of the treatment in reducing aqueous and SPMD concentrations of PCBs by a factor of 2-6. For the AC application in sediment, competitive sorption of the various solutes apparently requires a reduction by a factor of 16 of the literature values for the AC-water partitioning coefficient measured in pure aqueous systems. With this correction, model results and measurements agree within a factor of 3. After AC amendment is homogeneously mixed into the sediment and then left undisturbed, aqueous PCB concentrations tend toward the same reduction after 5 years. 19 refs., 5 figs., 4 tabs.

  7. Exposure to Chlorinated Biphenyls Causes Polymorphonucleocytes to Induce Progenitor Cell Toxicity in Culture

    Directory of Open Access Journals (Sweden)

    Tanika V. Martin

    2006-03-01

    Full Text Available Progenitor cells (PC are the precursors for many developmental structures and are sensitive to a variety of toxic agents including the environmental contaminants, polychlorinated biphenyls (PCBs. The mechanism(s that contributes to the development of PCB-induced progenitor cell-related fetotoxicities are not completely understood. However, several studies have demonstrated an important role for neutrophils (polymorphonucleocytes in the development of PCB induced toxicities. Our recent findings have indicated that conditioned medium collected from PC (CMPC exposed to a single dose of the PCB mixture, Aroclor 1248, can activate isolated neutrophil populations. Because of our recent findings, this study was conducted to determine if conditioned medium from PC treated with a PCB mixture causes neutrophils to injure PC in culture. Isolated PC were cultured and treated with different concentrations of Aroclor 1248 for 24 hours. The resulting PC-derived conditioned media was collected and its affect on neutrophil activity was analyzed. Conditioned medium from PC treated with Aroclor 1248 was chemotactic for neutrophils. The conditioned medium from Aroclor 1248 treated-PC also stimulated neutrophils to release super oxide anion, cathepsin G and elastase into culture medium. Furthermore, the conditioned medium from Aroclor 1248 treated- PC was able to stimulate neutrophils to cause progenitor cell toxicity in co-cultures. The conditioned medium from Aroclor 1248 treated-PC was not toxic to individual neutrophil cultures or PC cultures. Moreover, the addition of a protease inhibitor to the co-cultures containing neutrophils and PC, afforded protection against neutrophil-induced cytotoxicity of PC. These data suggest that a PCB mixture can cause progenitor cells to produce a factor(s that activates neutrophils and stimulates them to damage PC populations in culture.

  8. Decontamination solutions for polychlorinated biphenyls (PCBs) in raw fish oils from environmentally contaminated sea fishes.

    Science.gov (United States)

    Fernández-González, R; Yebra-Pimentel, I; Martínez-Carballo, E; Simal-Gándara, J

    2014-01-15

    Fish oil has been identified as one of the most important contributors to the levels of polychlorinated biphenyls (PCBs) in food and feed products. In this study, PCB adsorption from fish oil onto activated carbon (AC), other sustainable adsorbents (mussel shell and wood waste ashes) and organic solvent such as ethanol were compared and optimized. Regarding to adsorbents, PCBs were extracted from fish oil by a 2.0% adsorbent material dose, during 6.0 h at 25 °C. Solvent extraction was carried out using 2 × 5.0 mL ethanol by manually stirring for 3.0 min, and then by Ultrasound-Assisted Solvent Extraction (UASE) for 5.0 min. The results showed that removal rates obtained by using adsorbent materials ranged from 0.0 to 10% for marker PCBs, from 0.0 to 37% for mono-ortho-PCBs, from 0.0 to 74% for PCB11 and from 0.0 to 95% for non-ortho-PCBs. Regarding to solvent extraction, ethanol was used by manually stirring and then by Ultrasound-Assisted Solvent Extraction (UASE). The samples were then centrifuged (2000 rpm/10 min) and the alcoholic phase was removed. With this method, removal efficiencies were much better (85-116%); nevertheless, high eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) removal rates (70-78 and 71-79%, respectively) were detected. We can conclude that adsorption with adsorbents depends on the geometry of PCB congeners, as well as both type of adsorption material and their origin, and that several sorption cycles are needed. Adsorption with ethanol could be the most effective methodology but nutritional quality was impaired, what makes necessary to look for other not so polar removal solvents.

  9. Enantioselective accumulation of chiral polychlorinated biphenyls in lotus plant (Nelumbonucifera spp.).

    Science.gov (United States)

    Dai, Shouhui; Wong, Charles S; Qiu, Jing; Wang, Min; Chai, Tingting; Fan, Li; Yang, Shuming

    2014-09-15

    Enantioselective accumulation of chiral polychlorinated biphenyls (PCBs) 91, 95, 136, 149, 176 and 183 was investigated in lotus plants (Nelumbonucifera spp.) exposed to these chemicals via spiked sediment, to determine uptake and possible biotransformation for aquatic phytoremediation purposes. The concentrations of most PCBs were greatest in roots at 60 d (19.6 ± 1.51-70.6 ± 6.14 μg kg(-1)), but were greatest in stems and leaves at 120 d (25.3 ± 6.14-95.5 ± 19.4 μg kg(-1) and 17.4 ± 4.41-70.4 ± 10.4 μg kg(-1), respectively). Total amounts were greatest at 120 d and significantly higher in roots than those in stems and in leaves (1,457 ± 220-5,852 ± 735 ng, 237 ± 47.1-902 ± 184 ng and 202 ± 60.3-802 ± 90.2 ng, respectively), but represented less than 0.51% of the total mass of PCBs added to sediments, indicating that lotus plants were unlikely to remove appreciable amounts of PCBs from contaminated sediments. Racemic PCB residues in sediment indicate no enantioselective biodegradation by sedimentary microbial consortia over the entire experiment. Preferential accumulation of the (-)-enantiomers of PCBs 91, 95 and 136 were observed in roots, stems and leaves, but non-enantioselective accumulation was observed for PCBs 149, 176 and 183. These results indicate that aquatic plants can accumulate PCBs enantioselectively via root uptake, possibly by biotransformation within plant tissues as observed for terrestrial plants. This is also the first report to identify optical rotation of the atropisomers of PCBs 91 and 95.

  10. Polychlorinated biphenyls and breast cancer: A congener-specific meta-analysis.

    Science.gov (United States)

    Leng, Ling; Li, Jing; Luo, Xiu-mei; Kim, Jun-young; Li, Yi-meng; Guo, Xue-mei; Chen, Xi; Yang, Qiao-yun; Li, Guang; Tang, Nai-jun

    2016-03-01

    The incidence of breast cancer is related to various risk factors, especially that the environmental and lifestyle factors account for major contribution at the rate of 70% to 95% over all. However, there still remains some controversy over the epidemiological evidence regarding the effects of environmental carcinogens on the risk of breast cancer. We conducted a quantitative meta-analysis aiming at full evaluation of the effects of polychlorinated biphenyls (PCBs) on breast cancer in a congener-specific fashion. Four online literature databases were systematically searched before 1st January 2015, for studies stating correlation between PCB congeners and breast cancer. The Newcastle-Ottawa Scale was used to evaluate the quality of the studies that were included in our analysis. Sixteen studies were included in our final meta-analysis after screening based on the priori inclusion criteria. Nine PCB congeners were reported by more than two studies and they were presented in detail. The pooled Odds Ratios (ORs) showed a significant increase in the risk of breast cancer in individuals with higher plasma/fat levels of PCB 99 (OR: 1.36; 95% CI: 1.02 to 1.80), PCB 183 (OR: 1.56; 95% CI: 1.25 to 1.95) and PCB 187 (OR: 1.18; 95% CI: 1.01 to 1.39). Besides, the outcomes did not support a relationship between dioxin-like PCB congeners and the risk of breast cancer. The results of our meta-analysis imply that PCB 99, PCB 183 and PCB 187 would increase the risk of breast cancer. The mechanism of this increased risk may be by the induction of the CYP2B family in cytochrome P450 enzymes.

  11. Assessing the Global and Arctic Transport of Polychlorinated Biphenyls Under Present and Future Climate and Emissions

    Science.gov (United States)

    Friedman, C. L.; Selin, N. E.

    2014-12-01

    We simulate the present and potential future atmospheric transport and fate of polychlorinated biphenyls (PCBs), using the global chemical transport model GEOS-Chem. PCBs are toxic, persistent, and bioaccumulative chemicals whose production and use have been banned internationally. PCBs continue to cycle through the global atmosphere, however, because of their persistence, passive emissions from remaining stocks, and release from natural storage reservoirs such as oceans or soils. In particular, PCBs have been shown to transport long distances in the atmosphere to locations remote from emissions, such as the Arctic, where they can accumulate in wildlife and humans, putting health at risk. Previous studies have suggested that PCBs may be remobilized in a changing climate because higher temperatures will cause greater re-emissions from surface reservoirs. Here, we modify GEOS-Chem to simulate atmospheric PCB transport and investigate the relative effects of predicted climate changes and projected declines in primary emissions, especially on transport to the Arctic. We quantify changes in atmospheric concentrations of two PCBs (CB28 and CB 153) under 2050 climate ("FC"); 2050 emissions ("FE"); and 2050 climate and emissions combined ("FCFE"); relative to a 2000 climate, 2000 emissions control scenario, and determine the major processes affecting these changes. In the version of the model presented here, only soil-atmosphere surface interactions are considered, though future versions will include interaction with other surface media. Our results suggest projected 2050 emissions will play a stronger role than 2050 climate in controlling PCB concentrations of different volatilities. Temperature increases under FC cause increases in emissions of only 4% at most, resulting in negligible concentration changes relative to the FE scenario, in which primary emissions are projected to decline to <0.05% of present-day. Thus, the concentrations in the combined FCFE scenario are

  12. Formula for the Removal and Remediation of Polychlorinated Biphenyls in Painted Structures

    Science.gov (United States)

    Quinn, Jacqueline; Loftin, Kathleen; Geiger, Cherie

    2010-01-01

    An activated metal treatment system (AMTS) removes and destroys polychlorinated biphenyls (PCBs) found in painted structures or within the binding or caulking material on structures. It may be applied using a "paint-on and wipe-off" process that leaves the structure PCB-free and virtually unaltered in physical form. AMTS is used in conjunction with a solvent solution capable of donating hydrogen atoms. AMTS as a treatment technology has two functions: first, to extract PCBs from the material, and second, to degrade the extracted PCBs. The process for removing PCBs from structures is accomplished as an independent step to the degradation process. The goal is to extract the PCBs out of the paint, without destroying the paint, and to partition the PCBs into an environmentally friendly solvent. The research to date indicates this can be accomplished within the first 24 hours of AMTS contact with the paint. PCBs are extremely hydrophobic and prefer to be in the AMTS over the hardened paint or binder material. The solvent selected must be used to open, but not to destroy, the paint s polymeric lattice structure, allowing pathways for PCB movement out of the paint and into the solvent. A number of solvent systems were tested and are available for use within the AMTS. The second process of the AMTS is the degradation or dehalogenation of the PCBs. The solvent selection for this process is limited to solvents that are capable of donating a hydrogen atom to the PCB structure. Additional AMTS formulation properties that must be addressed for each site-specific application include viscosity and stability. The AMTS must be thick enough to remain where it is applied. Several thickening agents have been tested. Adding a stabilizing agent ensures that the AMTS will not evaporate and leave unprotected, activated metal exposed. During AMTS formulation testing, a number of reagents were evaluated to ensure the rate of dehalogenation was not inhibited by its addition to the system.

  13. Biodegradation of polychlorinated biphenyls (PCBs by the novel identified cyanobacterium Anabaena PD-1.

    Directory of Open Access Journals (Sweden)

    Hangjun Zhang

    Full Text Available Polychlorinated biphenyls (PCBs, a class of hazardous pollutants, are difficult to dissipate in the natural environment. In this study, a cyanobacterial strain Anabaena PD-1 showed good resistance against PCB congeners. Compared to a control group, chlorophyll a content decreased 3.7% and 11.7% when Anabaena PD-1 was exposed to 2 and 5 mg/L PCBs for 7 d. This cyanobacterial strain was capable of decomposing PCB congeners which was conclusively proved by determination of chloride ion concentrations in chlorine-free medium. After 7 d, the chloride ion concentrations in PCB-treated groups (1, 2, 5 mg/L were 3.55, 3.05, and 2.25 mg/L, respectively. The genetic information of strain PD-1 was obtained through 16S rRNA sequencing analysis. The GenBank accession number of 16S rRNA of Anabaena PD-1 was KF201693.1. Phylogenetic tree analysis clearly indicated that Anabaena PD-1 belonged to the genus Anabaena. The degradation half-life of Aroclor 1254 by Anabaena PD-1 was 11.36 d; the total degradation rate for Aroclor 1254 was 84.4% after 25 d. Less chlorinated PCB congeners were more likely to be degraded by Anabaena PD-1 in comparison with highly chlorinated congeners. Meta- and para-chlorines in trichlorodiphenyls and tetrachlorobiphenyls were more susceptible to dechlorination than ortho-chlorines during the PCB-degradation process by Anabaena PD-1. Furthermore, Anabaena PD-1 can decompose dioxin-like PCBs. The percent biodegradation of 12 dioxin-like PCBs by strain PD-1 ranged from 37.4% to 68.4% after 25 days. Results above demonstrate that Anabaena PD-1 is a PCB-degrader with great potential for the in situ bioremediation of PCB-contaminated paddy soils.

  14. Polychlorinated biphenyls in the exterior caulk of San Francisco Bay Area buildings, California, USA.

    Science.gov (United States)

    Klosterhaus, Susan; McKee, Lester J; Yee, Donald; Kass, Jamie M; Wong, Adam

    2014-05-01

    Extensive evidence of the adverse impacts of polychlorinated biphenyls (PCBs) to wildlife, domestic animals, and humans has now been documented for over 40 years. Despite the ban on production and new use of PCBs in the United States in 1979, a number of fish consumption advisories remain in effect, and there remains considerable uncertainty regarding ongoing environmental sources and management alternatives. Using a blind sampling approach, 25 caulk samples were collected from the exterior of ten buildings in the San Francisco Bay Area and analyzed for PCBs using congener-specific gas chromatography-mass spectrometry (GC-MS) and chlorine using portable X-ray fluorescence (XRF). PCBs were detected in 88% of the caulk samples collected from the study area buildings, with 40% exceeding 50 ppm. Detectable PCB concentrations ranged from 1 to 220,000 ppm. These data are consistent with previous studies in other cities that have identified relatively high concentrations of PCBs in concrete and masonry buildings built between 1950 and 1980. Portable XRF was not a good predictor of the PCB content in caulk and the results indicate that portable XRF analysis may only be useful for identifying caulk that contains low concentrations of Cl (≤ 10,000 ppm) and by extension low or no PCBs. A geographic information system-based approach was used to estimate that 10,500 kg of PCBs remain in interior and exterior caulk in buildings located in the study area, which equates to an average of 4.7 kg PCBs per building. The presence of high concentrations in the exterior caulk of currently standing buildings suggests that building caulk may be an ongoing source of PCBs to the San Francisco Bay Area environment. Further studies to expand the currently small international dataset on PCBs in caulking materials in buildings of countries that produced or imported PCBs appear justified in the context of both human health and possible ongoing environmental release.

  15. Seasonal variation of atmospheric polychlorinated biphenyls and polychlorinated naphthalenes in Japan

    Science.gov (United States)

    Hogarh, Jonathan N.; Seike, Nobuyasu; Kobara, Yuso; Masunaga, Shigeki

    2013-12-01

    This study investigated the seasonality of atmospheric polychlorinated biphenyls (PCBs) and polychlorinated naphthalenes (PCNs) in Japan. Polyurethane foam (PUF) disk passive air samplers (PAS) were deployed simultaneously at 55 sites in spring 2008, summer 2008 and winter 2008/09. Sampler deployment spanned 8 continuous weeks in each season. The non-outlier ranges of the two pollutants (ng/sample) were as follows; ∑190PCBs: 6.5-38.6 (spring), 43.5-220.5 (summer) and 25.9-136 (winter); and ∑63PCNs: 0.4-3.9 (spring), 0.7-7.1 (summer) and 1.1-9.2 (winter). The corresponding values in air were ∑190PCBs (pg m-3): 33-197 (spring), 222-1125 (summer) and 132-694 (winter); and ∑63PCNs (pg m-3): 2.2-20 (spring), 3.5-36 (summer) and 5.7-47 (winter), when sampling rate of 3.5 m3 day-1 was assumed. Thus, the PCBs peaked in summer, while the PCNs mostly peaked in winter; there was an apparent contrast in their seasonality in Japan. For the PCNs, seasonal variability was significant at rural than urban sites. Normally, POPs would show relatively increased air content in summer due to vaporization effect. The PCNs appeared to deviate from such a trend because of overriding input of tri-CNs presumably transported from long range by northwesterly winds in the winter season. The dioxin-like fractions of either pollutant were reduced in winter by about 30-50%.

  16. Recycling of transformer oil contaminated by polychlorinated biphenyls (PCBs) using catalytic hydrodechlorination.

    Science.gov (United States)

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

    2009-04-01

    Catalytic hydrodechlorination of polychlorinated biphenyls (PCBs) in the presence of transformer oil was carried out in a batch mode to detoxify PCBs and to recycle the treated oil. Various metal supported catalysts, including 0.98 wt% Pt, 0.79 wt% Pd and 12.8 wt% Ni on gamma -alumina (gamma -Al(2)O(3)) support, and 57.6 wt% Ni on silicon oxide-aluminum oxide (SiO(2)-Al(2)O(3)) support were used for the hydrodechlorination. Metal particle size of the Pt catalyst was 2.0 nm and metal particle sizes of the Pd and Ni catalysts were in the range of 6.4-6.9 nm. Various supercritical fluids, supercritical carbon dioxide (scCO(2)), supercritical propane (scPropane), supercritical dimethyl ether (scDME) and supercritical isobutane (scIsobutane) were used as reaction media. PCBs conversion, dechlorination degree of PCBs, was measured using gas chromatograph (GC) with an electron capture detector (ECD). The hydrodechorination degree increased in the order Ni > Pd > Pt, possibly due to higher metal loading and larger metal size of the Ni catalysts. At temperatures below 175 degrees C, scCO(2) was effective as the reaction media for the catalytic hydrodechlorination of PCBs in the presence of the transformer oil. However, PCBs conversion decreased significantly when the hydrodechlorination was carried out in a homogeneous phase with using scPropane, scDME or scIsobutane as a reaction medium. This was attributed to dilution effect of the supercritical fluids. Molecular weights of the transformer oils before and after the catalytic hydrodechlorination were analyzed using high-performance size exclusion chromatography (HPSEC). The molecular weight of the treated oil with 100 % PCBs conversion did not change after the catalytic hydrodechlorination at 200 degrees C. This process has proven to be effective to detoxify PCBs containing transformer oil and to recycle the treated oil.

  17. Dechlorination of polychlorinated biphenyls in transformer oil using UV and visible light.

    Science.gov (United States)

    Kong, Jiansong; Achari, Gopal; Langford, Cooper H

    2013-01-01

    A study on dechlorination of PCB138 in transformer oil (TO) and 2-propanol (IPA) using 254 nm ultraviolet (UV) light as well as dye sensitized visible light has been conducted. Studies on dechlorination of polychlorinated biphenyls (PCBs) in TO using visible light in the presence of methylene blue (MB) and triethylamine (TEA) (providing a 'photocatalytic' cycle) in both deaerated and aerated conditions have been conducted to determine effects of TO, MB and TEA on reaction rates. The results show that photolytic methods are effective in treating PCBs in TO, and that the oil plays a limited adverse role. Under UV irradiation, PCB 138 can be >99% dechlorinated in the presence 0.06% (w/w) TO in IPA within 1 h with a rate constant of 0.0853 min(-1), while 47% of PCB138 can be dechlorinated in 92.1% (w/w) TO in IPA within 2 h with a rate constant of 0.0051 min(-1). In the 'photocatalytic' system, 94% reduction of PCB 138 was achieved within 30 min with a rate constant of 0.0968 min(-1) when the solvent was 60.70% (w/w) TO in IPA, while 71% dechlorination of PCB138 was achieved within 30 min with a rate constant of 0.0382 min(-1) when 81.62% (w/w) TO was present. In treatment of 30-73 ppm PCBs in TO, the optimal concentration of MB and TEA were found to be 0.5 g/L and 58.08 g/L respectively. Because of quenching by oxygen, deaeration of the solution is necessary for an efficient reaction. The photocatalytic system is especially adapted for treating lower concentration of PCBs in TO.

  18. Gamma radiation process for destruction of toxic polychlorinated biphenyls (Pcbs) in transformer oils.

    Science.gov (United States)

    Singh, R K; Nayak, Poonam; Niyogi, U K; Khandal, R K; Singh, Gurdeep

    2006-01-01

    Polychlorinated biphenyls (PCBs) are synthetic organic chemicals commercially used worldwide in many applications. PCBs were used in oils because of their excellent properties such as good thermal stability, flame resistance, dielectric constant, high break down voltage, high boiling point and low volatility. However, because of their adverse affects on environment and human health, the use of PCBs has been banned now. PCBs are today considered among the widespread pollutants in the global system. PCBs sources still exist in various industrial products and in waste streams such as capacitor oils, lubricating oils, transformer oils, hydraulic oils, paints, rubbers, cables, etc. Several such materials containing PCBs emanating from various sources need to be detoxified before their reuse or before going to landfill for final disposal. Various remedial technologies have been developed in the world to destroy toxic PCBs. The radiolysis has been investigated as an environment-friendly process for waste oil treatment contaminated with PCBs, which may be a better alternative to the globally most widely accepted incineration method. A study was undertaken to detoxify PCBs in transformer oil by gamma radiation using Cobalt 60 source. Analysis of PCBs in transformer oils before and after radiation was carried out by GC-MS instrument. The effect of radiation dose and destruction of PCBs in transformer oils are discussed in details in the present paper. The method used was found to be highly effective and destruction was as high as 79 %. Further, the transformer oil samples were also evaluated before and after radiation to check their quality. The properties of oils were not significantly altered by gamma radiation treatment as evident from the results given in the paper.

  19. Phenolic Molding Compounds

    Science.gov (United States)

    Koizumi, Koji; Charles, Ted; de Keyser, Hendrik

    Phenolic Molding Compounds continue to exhibit well balanced properties such as heat resistance, chemical resistance, dimensional stability, and creep resistance. They are widely applied in electrical, appliance, small engine, commutator, and automotive applications. As the focus of the automotive industry is weight reduction for greater fuel efficiency, phenolic molding compounds become appealing alternatives to metals. Current market volumes and trends, formulation components and its impact on properties, and a review of common manufacturing methods are presented. Molding processes as well as unique advanced techniques such as high temperature molding, live sprue, and injection/compression technique provide additional benefits in improving the performance characterisitics of phenolic molding compounds. Of special interest are descriptions of some of the latest innovations in automotive components, such as the phenolic intake manifold and valve block for dual clutch transmissions. The chapter also characterizes the most recent developments in new materials, including long glass phenolic molding compounds and carbon fiber reinforced phenolic molding compounds exhibiting a 10-20-fold increase in Charpy impact strength when compared to short fiber filled materials. The role of fatigue testing and fatigue fracture behavior presents some insight into long-term reliability and durability of glass-filled phenolic molding compounds. A section on new technology outlines the important factors to consider in modeling phenolic parts by finite element analysis and flow simulation.

  20. Radiocarbon content of synthetic and natural semi-volatile halogenated organic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, C.M.; Xu Li; Eglinton, T.I.; Boon, J.P.; Faulkner, D.J

    2002-12-01

    New developments in molecular-level {sup 14}C analysis techniques enable clues about natural versus commercial synthesis of trace organic contaminants. - Some halogenated organic compounds, such as polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polybrominated diphenyl ethers (PBDEs), have been suggested to have natural sources but separating these compounds from their commercially synthesized counterparts is difficult. Molecular-level {sup 14}C analysis may be beneficial since most synthetic compounds are manufactured from petrochemicals ({sup 14}C-free) and natural compounds should have 'modern' or 'contemporary' {sup 14}C levels. As a baseline study, we measured, for the first time, the {sup 14}C abundance in commercial PCB and PBDE mixtures, a number of organochlorine pesticides, as well as one natural product 2-(3', 5'-dibromo-2'-methoxyphenoxy)-3,5-dibromoanisole. The latter compound was isolated from a marine sponge and is similar in structure to a PBDE. All of the synthetic compounds were {sup 14}C-free except for the pesticide toxaphene, which had a modern {sup 14}C abundance, as did the brominated natural compound. The result for toxaphene was not surprising since it was commercially synthesized by the chlorination of camphene derived from pine trees. These results suggest that measuring the {sup 14}C content of halogenated organic compounds may be quite useful in establishing whether organic compounds encountered in the environment have natural or synthetic origins (or both) provided that any synthetic counterparts derive from petrochemical feedstock.

  1. Nickel-catalyzed hydroliquefaction of Morwell brown coal at low temperatures using phenolic compounds as solvents

    Energy Technology Data Exchange (ETDEWEB)

    Takemura, Y.; Saito, Y.; Okada, K.; Koinuma, Y.

    To attain a more effective coal liquefaction process, low-temperature (230-270 degrees C) coal hydroliquefaction was performed by using 15 kinds of single- or double-ring phenolic compounds as solvents and nickel acetate as a catalyst precursor. The role of the phenolic compound in the liquefaction reaction is discussed. With selected compounds, such as 1,7-dihydroxynaphthalene and resorcinol, Morwell brown coal was catalytically liquefied in a batch autoclave under H/sub 2/ pressure (10 MPa, cold) to give the coversions of the coal (to benzene/ethanol mixture solubles), which are higher than 70 wt%, at 270 degrees C for 1 h. Among three dihydroxybenzenes, resorcinol showed the highest efficiency for the Ni-catalyzed hydroliquefaction of the coal, though the capability of resorcinol to dissolve coal is the lowest in the absence of H/sub 2/. Capabilities of o-phenylphenol and its related compounds to dissolve the coal at 250 degrees C under Ar pressure (10 MPa, cold) and to hydroliquefy the coal at 270 degrees C under H/sub 2/ pressure (10 MPa, cold) were quantified. The respective orders of the conversion of the coal with these compounds are as follows: o-phenylphenol approximately equal to o-cyclohexylphenol > biphenyl approximately equal to cyclohexylbenzene. At this temperature, the solvent effect of phenolic functionality is larger than that of the hydroaromatic one. The same result is found with 1-naphthol and 5,6,7,8-tetrahydro-1-naphthol. 20 refs., 4 tabs.

  2. Biosynthesis of biphenyls and benzophenones--evolution of benzoic acid-specific type III polyketide synthases in plants.

    Science.gov (United States)

    Beerhues, Ludger; Liu, Benye

    2009-01-01

    Type III polyketide synthases (PKSs) generate a diverse array of secondary metabolites by varying the starter substrate, the number of condensation reactions, and the mechanism of ring closure. Among the starter substrates used, benzoyl-CoA is a rare starter molecule. Biphenyl synthase (BIS) and benzophenone synthase (BPS) catalyze the formation of identical linear tetraketide intermediates from benzoyl-CoA and three molecules of malonyl-CoA but use alternative intramolecular cyclization reactions to form 3,5-dihydroxybiphenyl and 2,4,6-trihydroxybenzophenone, respectively. In a phylogenetic tree, BIS and BPS group together closely, indicating that they arise from a relatively recent functional diversification of a common ancestral gene. The functionally diverse PKSs, which include BIS and BPS, and the ubiquitously distributed chalcone synthases (CHSs) form separate clusters, which originate from a gene duplication event prior to the speciation of the angiosperms. BIS is the key enzyme of biphenyl metabolism. Biphenyls and the related dibenzofurans are the phytoalexins of the Maloideae. This subfamily of the Rosaceae includes a number of economically important fruit trees, such as apple and pear. When incubated with ortho-hydroxybenzoyl (salicoyl)-CoA, BIS catalyzes a single decarboxylative condensation with malonyl-CoA to form 4-hydroxycoumarin. A well-known anticoagulant derivative of this enzymatic product is dicoumarol. Elicitor-treated cell cultures of Sorbus aucuparia also formed 4-hydroxycoumarin when fed with the N-acetylcysteamine thioester of salicylic acid (salicoyl-NAC). BPS is the key enzyme of benzophenone metabolism. Polyprenylated benzophenone derivatives with bridged polycyclic skeletons are widely distributed in the Clusiaceae (Guttiferae). Xanthones are regioselectively cyclized benzophenone derivatives. BPS was converted into a functional phenylpyrone synthase (PPS) by a single amino acid substitution in the initiation/elongation cavity. The

  3. Synthesis, Characterization and Fluorescence Properties of Europium, Terbium Complexes with Biphenyl-4-Carboxylic Acid and o-Phenanthroline

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Two series of solid complexes of europium and terbium with biphenyl 4-carboxylic acid and phen were synthesized and characterized in this report. Their elemental analysis, molar conductivities and TG-DTA studies indicate that the complexes have the composition of Eu(phen)L3·1/2H2O, Eu0.5RE0.5(phen)L3·1/2H2O; Tb(phen)L3·H2O and Tb0.5RE0.5(Phen)L3·1/2H2O. (RE=Y3+, La3+ and Gd3+; L=biphenyl 4-carboxylic acid; phen=o-Phenanthroline). The studies of their IR, UV 1H NMR and molar conductivities demonstrate that biphenyl 4-carboylic acid is bounded with RE(Ⅲ) ion. Rare earth ions coordinate with two nitrogen atoms of phen molecules directly in these rare earth complexes. The fluorescence spectra and fluorescence lifetimes of the rare earth complexes show that the fluorescent intensity and lifetime of a series of europium complexes are longer than those of the series of terbium complexes as having the some ligands. There are better fluorescent intensity and lifetime of hetero-nuclear rare earth complexes than homo-nuclear rare earth complexes for europium complexes. The fluorescence emission intensity of Eu3+ is raised by inert fluorescent rare earth ions (Y3+, Gd3+ and La3+), but in Tb3+ hetero-nuclear rare earth complexes the intensity of Tb3+ ions are quenched by the inert fluorescent rare earth ions.

  4. On the nature of lithium biphenyl in ethereal solvents. A critical analysis unifying DFT calculations, physicochemical data in solution, and a X-ray structure.

    Science.gov (United States)

    de la Viuda, Mónica; Yus, Miguel; Guijarro, Albert

    2011-12-15

    The lithium ion is an important type of electrolyte that has technological applications in the manufacture of lithium ion cells; therefore, a better understanding of the nature of its solutions is desirable. When associated to the radical anion of biphenyl in an organic solvent, it forms conducting solutions comparable to strong electrolytes such as lithium perchlorate. We have studied the lithium biphenyl solution in dimethoxyethane using DFT calculations. The nature of these ionic solutions is described in terms of a dynamic equilibrium between different types of ionic associations, the composition of which depends on the solvent and the temperature. The X-ray structure of [Li(+)·4C(5)H(10)O][C(12)H(10)(•-)], a solvent-separated ion pair of lithium biphenyl complexed with tetrahydropyran, is reported. Its main structural characteristics coincide with the calculated one, which we think is the dominant species at room temperature, in agreement with the available physicochemical data.

  5. Interpenetrating 2D Manganese(Ⅱ) Coordination Polymer Supported by 4,4'-Bis(dimethoxyphosphorylmethyl)-biphenyl Ligands

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiangdong; GE Chunhua; YIN Jing; ZHAO Yang; HE Cui

    2009-01-01

    A novel coordination polymer [Mn(bdpbp)2(NO3)2] n (1), where bdpbp=4,4'-bis(dimethoxyphosphoryl-methyl)biphenyl, was prepared under mild condition. The structure has been determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectra, luminescent property and thermo-gravimetric analyses. Structure of 1 exhibits infinite grid frameworks and forms two fold interpenetrating nets.Weak C--H…O hydrogen bonds ensure the formation and stability of a three dimensional supramolecular network.

  6. The concentrations of radionuclides, heavy metals, and poloychlorinated biphenyls in field mice collected from regional background areas. Revision 3

    Energy Technology Data Exchange (ETDEWEB)

    Fresquez, Philip R. [Los Alamos National Laboratory

    2016-01-21

    Field mice are effective indicators of contaminant presence. This paper reports the concentrations of various radionuclides, heavy metals, polychlorinated biphenyls, high explosives, perchlorate, and dioxin/furans in field mice (mostly deer mice) collected from regional background areas in northern New Mexico. These data, represented as the regional statistical reference level (the mean plus three standard deviations = 99% confidence level), are used to compare with data from field mice collected from areas potentially impacted by Laboratory operations, as per the Environmental Surveillance Program at Los Alamos National Laboratory.

  7. Mucinous gastric hyperplasia in a colony of rhesus monkeys (Macaca mulatta) induced by polychlorinated biphenyl (Aroclor 1254)

    Energy Technology Data Exchange (ETDEWEB)

    Geistfeld, J.G.; Bond, M.G.; Bullock, B.C.; Varian, M.C.

    1982-02-01

    Since 1971, 45 of 259 male rhesus monkeys housed in a primate building have died of a chronic and progressive disease characterized by diarrhea, dehydration, weakness, gingivitis, emaciation, and alopecia. The principal necropsy finding in these monkeys, and in eight others killed for experimental purposes, was hypertrophic and hyperplastic mucinous gastropathy involving both the mucosa and submucosa. The toxic agent involved was identified as the polychlorinated biphenyl (PCB), Aroclor 1254. The suspected source of the toxic agent was a concrete sealer used during building construction.

  8. 多氯联苯的非生物降解%Research in abiological degradation of polychlorinated biphenyls

    Institute of Scientific and Technical Information of China (English)

    帅建军; 熊飞; 郑建立; 彭日荷; 姚泉洪; 熊爱生

    2011-01-01

    Polychlorinated biphenyls( PCBs) are persistent organic pollutants(POPs) widely distributed in environment.Here the abiological degradation is reviewed in terms of types,mechanisms,advantages and disadvantages, and the prospects of remediation of PCBs contamination are also discussed .%综述了多氯联苯非生物降解的类型、机理,分析了多氯联苯非生物降解的优势及不足之处,并对今后多氯联苯污染的修复前景进行了预测和展望.

  9. Long-term in vivo polychlorinated biphenyl 126 exposure induces oxidative stress and alters proteomic profile on islets of Langerhans

    OpenAIRE

    2016-01-01

    It has been recently proposed that exposure to polychlorinated biphenyls (PCBs) is a risk factor to type 2 diabetes mellitus (DM2). We investigated this hypothesis using long-term in vivo PCB126 exposure to rats addressing metabolic, cellular and proteomic parameters. Male Wistar rats were exposed to PCB126 (0.1, 1 or 10 μg/kg of body weight/day; for 15 days) or vehicle by intranasal instillation. Systemic alterations were quantified by body weight, insulin and glucose tolerance, and blood bi...

  10. OXIDATION OF POLYCHLORINATED BIPHENYLS BY LIVER TISSUE SLICES FROM PHENOBARBITAL-PRETREATED MICE IS CONGENER-SPECIFIC AND ATROPSELECTIVE

    OpenAIRE

    Wu, Xianai; Duffel, Michael; Lehmler, Hans-Joachim

    2013-01-01

    Mouse models are powerful tools to study the developmental neurotoxicity of polychlorinated biphenyls (PCBs); however, studies of the oxidation of chiral PCB congeners to potentially neurotoxic hydroxylated metabolites (OH-PCBs) in mice have not been reported. Here we investigate the atropselective oxidation of chiral PCB 91 (2,2',3,4',6-pentachlorobiphenyl), PCB 95 (2,2',3,5',6-pentachlorobiphenyl), PCB 132 (2,2',3,3',4,6'-hexachlorobiphenyl), PCB 136 (2,2',3,3',6,6'-hexachlorobiphenyl) and ...

  11. Light-induced reversible modification of the work function of a new perfluorinated biphenyl azobenzene chemisorbed on Au (111)

    Science.gov (United States)

    Masillamani, Appan Merari; Osella, Silvio; Liscio, Andrea; Fenwick, Oliver; Reinders, Federica; Mayor, Marcel; Palermo, Vincenzo; Cornil, Jérôme; Samorì, Paolo

    2014-07-01

    We describe the synthesis of a novel biphenyl azobenzene derivative exhibiting: (i) a protected thiol anchoring group in the α-position to readily form self-assembled monolayers (SAMs) on Au surfaces; and (ii) a terminal perfluorinated benzene ring in the ω-position to modify the surface properties. The design of this molecule ensured both an efficient in situ photoswitching between the trans and cis isomers when chemisorbed on Au(111), due to the presence of a biphenyl bridge between the thiol protected anchoring group and the azo dye, and a significant variation of the work function of the SAM in the two isomeric states, induced by the perfluorinated phenyl head group. By exploiting the light responsive nature of the chemisorbed molecules, it is possible to dynamically modify in situ the work function of the SAM-covered electrode, as demonstrated both experimentally and by quantum-chemical calculations, revealing changes in work function up to 220 meV. These findings are relevant for tuning the work function of metallic electrodes, and hence to dynamically modulate charge injection at metal-semiconductor interfaces for organic opto-electronic applications.We describe the synthesis of a novel biphenyl azobenzene derivative exhibiting: (i) a protected thiol anchoring group in the α-position to readily form self-assembled monolayers (SAMs) on Au surfaces; and (ii) a terminal perfluorinated benzene ring in the ω-position to modify the surface properties. The design of this molecule ensured both an efficient in situ photoswitching between the trans and cis isomers when chemisorbed on Au(111), due to the presence of a biphenyl bridge between the thiol protected anchoring group and the azo dye, and a significant variation of the work function of the SAM in the two isomeric states, induced by the perfluorinated phenyl head group. By exploiting the light responsive nature of the chemisorbed molecules, it is possible to dynamically modify in situ the work function of

  12. Comparison of solvent extraction and solid-phase extraction for the determination of polychlorinated biphenyls in transformer oil.

    Science.gov (United States)

    Mahindrakar, A N; Chandra, S; Shinde, L P

    2014-01-01

    Solid-phase extraction (SPE) of nine polychlorinated biphenyls (PCBs) from transformer oil samples was evaluated using octadecyl (CI8)-bonded porous silica. The efficiency of SPE of these PCBs was compared with those obtained by solvent extraction with DMSO and hexane. Average recoveries exceeding 95% for these PCBs were obtained via the SPE method using small cartridges containing 100mg of 40 pm CI8-bonded porous silica. The average recovery by solvent extraction with DMSO and hexane exceeded 83%. It was concluded that the recoveries and precision for the solvent extraction of PCBs were poorer than those for the SPE.

  13. Decreased sex ratio following maternal exposure to polychlorinated biphenyls from contaminated Great Lakes sport-caught fish: a retrospective cohort study.

    Directory of Open Access Journals (Sweden)

    Anderson Henry A

    2003-03-01

    Full Text Available Abstract Background Fish from the Great Lakes are contaminated with polychlorinated biphenyls, which have been found to have several adverse reproductive effects. Several environmental contaminants have been found to alter the sex ratio of offspring at birth, but the evidence of such an effect of polychlorinated biphenyls has been inconsistent. Methods We examined parental serum polychlorinated biphenyl concentration in relation to the sex ratio of 173 children of mothers and 208 children of fathers from the Great Lakes region of the United States between 1970 and 1995. We calculated odds ratios for a male child using logistic regression and generalized estimating equations with adjustment for the year of birth of the child, maternal and paternal age, the mother's parity at the child's birth, and whether the child had an older brother. Results The adjusted odds ratio for having a male child among mothers in the highest quintile of serum polychlorinated biphenyl concentration was 0.18 (95% CI: 0.06–0.59 compared to mothers in the lowest quintile. Treating exposure as a continuous variable, the adjusted odds ratio for having a male child was 0.54 per unit increase in the natural log of maternal serum polychlorinated biphenyl concentration (95% CI: 0.33–0.89. There was little evidence of an association with paternal exposure. We found no association between either maternal or paternal serum dichlorodiphenyl-dichloroethene concentration and the sex ratio. Conclusions These findings suggest that maternal exposure to polychlorinated biphenyls may decrease the sex ratio of offspring. These data add to the growing body of evidence that exposure to particular chemicals can alter the sex ratio at birth.

  14. Highly trifluoromethylated platinum compounds.

    Science.gov (United States)

    Martínez-Salvador, Sonia; Forniés, Juan; Martín, Antonio; Menjón, Babil

    2011-07-11

    The homoleptic, square-planar organoplatinum(II) compound [NBu(4)](2) [Pt(CF(3))(4)] (1) undergoes oxidative addition of CF(3) I under mild conditions to give rise to the octahedral organoplatinum(IV) complex [NBu(4)](2) [Pt(CF(3))(5)I] (2). This highly trifluoromethylated species reacts with Ag(+) salts of weakly coordinating anions in Me(2)CO under a wet-air stream to afford the aquo derivative [NBu(4)][Pt(CF(3))(5) (OH(2))] (4) in around 75% yield. When the reaction of 2 with the same Ag(+) salts is carried out in MeCN, the solvento compound [NBu(4) ][Pt(CF(3))(5)(NCMe)] (5) is obtained in around 80% yield. The aquo ligand in 4 as well as the MeCN ligand in 5 are labile and can be cleanly replaced by neutral and anionic ligands to furnish a series of pentakis(trifluoromethyl)platinate(IV) compounds with formulae [NBu(4)][Pt(CF(3))(5) (L)] (L=CO (6), pyridine (py; 7), tetrahydrothiophene (tht; 8)) and [NBu(4)](2) [Pt(CF(3))(5)X] (X=Cl (9), Br (10)). The unusual carbonyl-platinum(IV) derivative [NBu(4)][Pt(CF(3))(5) (CO)] (6) is thermally stable and has a ν(CO) of 2194 cm(-1). The crystal structures of 2⋅CH(2)Cl(2), 5, [PPh(4) ][Pt(CF(3))(5)(CO)] (6'), and 7 have been established by X-ray diffraction methods. Compound 2 has shown itself to be a convenient entry to the chemistry of highly trifluoromethylated platinum compounds. To the best of our knowledge, compounds 2 and 4-10 are the organoelement compounds with the highest CF(3) content to have been isolated and adequately characterized to date.

  15. Flame retardants, polychlorinated biphenyls and insecticides in pregnant women in the northern part of The Netherlands

    Energy Technology Data Exchange (ETDEWEB)

    Meijer, L.; Sauer, P. [Beatrix Childrens Hospital, University Hospital Groningen (Sweden); Weiss, J.; Bergman, A. [Stockholm Univ. (Sweden). Dept. of Environmental Chemistry; Velzen, M. van; Brouwer, A. [Free Univ., Amsterdam (Netherlands). Inst. for Environmental Studies

    2004-09-15

    Organohalogens (OHS) are compounds with lipophilic properties, which accumulate in the environment, wildlife and humans. Human exposure is mainly through dietary intake of animal fat. After exposure the compounds are slowly metabolised leading to accumulation, mainly in the adipose tissue. During pregnancy the compounds are transported across the placenta to the fetus. OHS have an adverse effect on human health, these adverse effects are more likely to be seen in developing fetus. In 2001 the Compare project (supported by the European Union) started with the aim to examine the exposure-effect pathways to different kinds of organohalogen compounds. Therefore a cohort was founded in which 90 pregnant women living in the northern part of the Netherlands participated, the Dutch Groningen Infant Cohort. In this cohort p,p'-DDE, PCB-153, 4OH-PCB- 107, 4OH-PCB-146, 4OH-PCB-187, PCP, BDE-47, 6OH-BDE-47, BDE-99, BDE-100, BDE-153, BDE-154 and HBCDD were determined in blood samples taken in the 20{sup th} and 35{sup th} week of pregnancy. Transplacental transfer of these compounds was determined by analyzing the cord blood samples of the infants. The infants were followed for 1 1/2 years to examine the influence of the compounds on their development. In this short paper the results of the levels of the selected OHS in pregnant women are presented.

  16. Compound semiconductor device physics

    CERN Document Server

    Tiwari, Sandip

    2013-01-01

    This book provides one of the most rigorous treatments of compound semiconductor device physics yet published. A complete understanding of modern devices requires a working knowledge of low-dimensional physics, the use of statistical methods, and the use of one-, two-, and three-dimensional analytical and numerical analysis techniques. With its systematic and detailed**discussion of these topics, this book is ideal for both the researcher and the student. Although the emphasis of this text is on compound semiconductor devices, many of the principles discussed will also be useful to those inter

  17. A Reconnaissance of selected organic compounds in streams in tribal lands in Central Oklahoma, January-February 2009

    Science.gov (United States)

    Becker, Carol J.

    2010-01-01

    The U.S. Geological Survey worked in cooperation with the U.S. Environmental Protection Agency and the Kickapoo Tribe of Oklahoma on two separate reconnaissance projects carried out concurrently. Both projects entailed the use of passive samplers as a sampling methodology to investigate the detection of selected organic compounds at stream sites in jurisdictional areas of several tribes in central Oklahoma during January-February 2009. The focus of the project with the U.S. Environmental Protection Agency was the detection of pesticides and pesticide metabolites using Semipermeable Membrane Devices at five stream sites in jurisdictional areas of several tribes. The project with the Kickapoo Tribe of Oklahoma focused on the detection of pesticides, pesticide metabolites, polycyclic aromatic hydrocarbons, polychlorinated biphenyl compounds, and synthetic organic compounds using Semipermeable Membrane Devices and Polar Organic Chemical Integrative Samplers at two stream sites adjacent to the Kickapoo tribal lands. The seven stream sites were located in central Oklahoma on the Cimarron River, Little River, North Canadian River, Deep Fork, and Washita River. Extracts from SPMDs submerged at five stream sites, in cooperation with the U.S. Environmental Protection Agency, were analyzed for 46 pesticides and 6 pesticide metabolites. Dacthal, a pre-emergent herbicide, was detected at all five sites. Pendimethalin, also a pre-emergent, was detected at one site. The insecticides chlorpyrifos and dieldrin were detected at three sites and p,p'-DDE, a metabolite of the insecticide DDT, also was detected at three sites. SPMDs and POCIS were submerged at the upstream edge and downstream edge of the Kickapoo tribal boundaries. Both sites are downstream from the Oklahoma City metropolitan area and multiple municipal wastewater treatment plants. Extracts from the passive samplers were analyzed for 62 pesticides, 10 pesticide metabolites, 3 polychlorinated biphenyl compounds, 35

  18. Distribution, sources, and risk assessment of polychlorinated biphenyls in surface waters and sediments of rivers in Shanghai, China

    Science.gov (United States)

    Wang, Xueping; Han, Jingchao; Bi, Chunjuan; Huang, Xing; Jia, Jinpu; Chen, Zhenlou

    2016-10-01

    The distribution, sources, and potential risks of polychlorinated biphenyl (PCB) contamination in the rivers of Shanghai, China were investigated. Fourteen PCB congeners in surface waters and sediments, which were collected from 53 sampling sites, were quantified by gas chromatography-mass spectrometer (GC-MS). The total concentrations of PCBs in the dissolved phase, in particulates, and in sediments ranged from not detected (nd) to 34.8 ng•L‒1, from 0.76 to 39.71 ng•L‒1, and from 1.46 to 46.11 ng•g-1 (dry weight, dw), respectively. The corresponding WHO toxic equivalents (TEQs) of dioxinlike polychlorinated biphenyls (dl-PCBs) ranged between nd-1135.63 pg TEQ•L-1, 0.02-605.94 pg TEQ•L-1, and 0.05-432.12 pg TEQ•g-1 dw, respectively. The penta-CBs, especially PCB 118 and PCB 105, were the dominant congeners in all samples. Principle Component Analysis (PCA) indicated that the PCBs were mainly influenced by a historical accumulation of commercial PCB products, the burning of house coal, and emissions from municipal solid waste incineration (MSWI) and secondary metallurgy industries. The center of Shanghai was significantly affected by PCB contamination, followed by the industrial parklands and suburban towns, while the farmland of Chongming Island was the least affected area. Adverse biological and health effects would be likely in the central urban areas, industrial parks, and residential towns of Shanghai.

  19. Dioxins, furans, biphenyls, arsenic, thorium and uranium in natural and anthropogenic sources of phosphorus and calcium used in agriculture.

    Science.gov (United States)

    Avelar, A C; Ferreira, W M; Pemberthy, D; Abad, E; Amaral, M A

    2016-05-01

    The aim of this study was to assess the presence of dioxins, furans and biphenyls, and the inorganic contaminants such as arsenic (As), thorium (Th) and uranium (U) in three main products used in Agriculture in Brazil: feed grade dicalcium phosphate, calcined bovine bone meal and calcitic limestone. The first two are anthropogenic sources of phosphorus and calcium, while calcitic limestone is a natural unprocessed mineral. Regarding to dioxin-like substances, all samples analyzed exhibited dioxins (PCDD) and furans (PCDF) and dioxin-like polychlorinated biphenyls (dl-PCBs) concentrations below limit of detection (LOD). In general, achieved is in accordance with regulation in Brazil where is established a maximum limit in limestone used in the citric pulp production (0.50pg WHO-TEQ g(-1)). In addition, reported data revealed very low levels for limestone in comparison with similar materials reported by European legislation. As result for toxic metals, achieved data were obtained using Instrumental Neutron Activation Analysis (INAA). On one hand, limestone sample exhibits the largest arsenic concentration. On another hand, dicalcium phosphate exhibited the largest uranium concentration, which represents a standard in animal nutrition. Therefore, it is phosphorus source in the animal feed industry can be a goal of concern in the feed field.

  20. Fate and Complex Pathogenic Effects of Dioxins and Polychlorinated Biphenyls in Obese Subjects before and after Drastic Weight Loss

    Science.gov (United States)

    Kim, Min-Ji; Marchand, Philippe; Henegar, Corneliu; Antignac, Jean-Philippe; Alili, Rohia; Poitou, Christine; Bouillot, Jean-Luc; Basdevant, Arnaud; Le Bizec, Bruno; Barouki, Robert; Clément, Karine

    2011-01-01

    Background In humans, persistent organic pollutants (POPs) are stored primarily in adipose tissue. Their total body burden and their contribution to obesity-associated diseases remain unclear. Objectives We characterized POP total body burden and their redistribution in obese individuals before and after drastic weight loss and compared these values with a variety of molecular, biological, and clinical parameters. Methods Seventy-one obese subjects were enrolled and underwent bariatric surgery. Blood and adipose tissue samples were obtained at different times from these individuals as well as from 18 lean women. Results POP content (17 dioxins/furans and 18 polychlorinated biphenyl congeners) in different adipose tissue territories was similar, allowing us to assess total POP body burden from a single biopsy. Total POP body burden was 2 to 3 times higher in obese than in lean individuals. We also found increased expression of some POP target genes in obese adipose tissue. Drastic weight loss led to increased serum POPs and, within 6–12 months, to a significant 15% decrease in total polychlorinated biphenyl body burden. Importantly, serum POP levels were positively correlated with liver toxicity markers and lipid parameters, independently of age and body mass index. Conclusions POP content in adipose tissue and serum correlate with biological markers of obesity-related dysfunctions. Drastic weight loss leads to a redistribution of POPs and to a moderate decrease of their total body burden. PMID:21156398