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Walter Vetter - One of the best experts on this subject based on the ideXlab platform.

  • Synthesis and characterization of 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE) and structurally related Compounds evidenced in seal blubber and brain.
    Environmental science & technology, 2007
    Co-Authors: Roland Von Der Recke, Walter Vetter
    Abstract:

    The unknown Compound UBC-1 previously described as the major Organobromine contamination in the blubber extract of a hooded seal (Cystophora cristata) from the Barents Sea was identified as 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE). DPTE, which is the main component of the brominated flame retardant (BFR) Bromkal 73-5 PE, was synthesized by electrophilic addition of bromine to allyl-2,4,6-tribromophenyl ether (ATE). The chirality of DPTE was proven by gas chromatographic enantioseparation of the synthesized racemate. On the basis of GC/ECNI-MS ion chromatograms (m/z79 and 81), DPTE was the dominating Organobromine Compound in blubber and brain samples of hooded seals and harp seals (Phoca groenlandica) from the Barents and Greenland Seas. The concentrations of DPTE in blubber and brain were up to 470 and 340 microg/kg wet weight. Next to DPTE, the natural dibromo-trichloromonoterpene (MHC-1), the anthropogenic BDE 47 and BDE 99, as well as ATE, 3,5-dibromo-2-(2',4'-dibromo)-phenoxyanisole (6-MeO-BDE 47), 2-bromoallyl-2,4,6-tribromophenyl ether (BATE), and 4,6-dibromo-2-(2',4'-dibromo)-phenoxyanisole (2'-MeO-BDE 68) were present with decreasing relevance. BATE, which was detected for the first time in environmental samples, was synthesized from DPTE by E2 elimination. In brain samples of the harp seals, DPTE, ATE, and BATE were the most abundant Organobromine Compounds, whereas polybrominated diphenyl ethers (PBDEs) and MHC-1 were virtually absent. This indicated that DPTE, ATE, and BATE were able to penetrate the blood-brain barrier. The general co-occurrence of ATE and BATE in samples contaminated with DPTE support the hypothesis that these Compounds are biotransformation products of DPTE. Anaerobic transformation studies of DPTE with super-reduced corrinoids resulted in the formation of ATE. Furthermore, 2,4,6-tribromophenol (TBP) and two other unknown minor transformation products were detected.

  • synthesis and characterization of 2 3 dibromopropyl 2 4 6 tribromophenyl ether dpte and structurally related Compounds evidenced in seal blubber and brain
    Environmental Science & Technology, 2007
    Co-Authors: Roland Von Der Recke, Walter Vetter
    Abstract:

    The unknown Compound UBC-1 previously described as the major Organobromine contamination in the blubber extract of a hooded seal (Cystophora cristata) from the Barents Sea was identified as 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE). DPTE, which is the main component of the brominated flame retardant (BFR) Bromkal 73-5 PE, was synthesized by electrophilic addition of bromine to allyl-2,4,6-tribromophenyl ether (ATE). The chirality of DPTE was proven by gas chromatographic enantioseparation of the synthesized racemate. On the basis of GC/ECNI-MS ion chromatograms (m/z 79 and 81), DPTE was the dominating Organobromine Compound in blubber and brain samples of hooded seals and harp seals (Phoca groenlandica) from the Barents and Greenland Seas. The concentrations of DPTE in blubber and brain were up to 470 and 340 μg/kg wet weight. Next to DPTE, the natural dibromo-trichloro-monoterpene (MHC-1), the anthropogenic BDE 47 and BDE 99, as well as ATE, 3,5-dibromo-2-(2‘,4‘-dibromo)-phenoxyanisole (6-MeO-B...

Roland Von Der Recke - One of the best experts on this subject based on the ideXlab platform.

  • synthesis and characterization of 2 3 dibromopropyl 2 4 6 tribromophenyl ether dpte and structurally related Compounds evidenced in seal blubber and brain
    Environmental Science & Technology, 2007
    Co-Authors: Roland Von Der Recke, Walter Vetter
    Abstract:

    The unknown Compound UBC-1 previously described as the major Organobromine contamination in the blubber extract of a hooded seal (Cystophora cristata) from the Barents Sea was identified as 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE). DPTE, which is the main component of the brominated flame retardant (BFR) Bromkal 73-5 PE, was synthesized by electrophilic addition of bromine to allyl-2,4,6-tribromophenyl ether (ATE). The chirality of DPTE was proven by gas chromatographic enantioseparation of the synthesized racemate. On the basis of GC/ECNI-MS ion chromatograms (m/z 79 and 81), DPTE was the dominating Organobromine Compound in blubber and brain samples of hooded seals and harp seals (Phoca groenlandica) from the Barents and Greenland Seas. The concentrations of DPTE in blubber and brain were up to 470 and 340 μg/kg wet weight. Next to DPTE, the natural dibromo-trichloro-monoterpene (MHC-1), the anthropogenic BDE 47 and BDE 99, as well as ATE, 3,5-dibromo-2-(2‘,4‘-dibromo)-phenoxyanisole (6-MeO-B...

Roland Von Der Recke - One of the best experts on this subject based on the ideXlab platform.

  • Synthesis and characterization of 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE) and structurally related Compounds evidenced in seal blubber and brain.
    Environmental science & technology, 2007
    Co-Authors: Roland Von Der Recke, Walter Vetter
    Abstract:

    The unknown Compound UBC-1 previously described as the major Organobromine contamination in the blubber extract of a hooded seal (Cystophora cristata) from the Barents Sea was identified as 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE). DPTE, which is the main component of the brominated flame retardant (BFR) Bromkal 73-5 PE, was synthesized by electrophilic addition of bromine to allyl-2,4,6-tribromophenyl ether (ATE). The chirality of DPTE was proven by gas chromatographic enantioseparation of the synthesized racemate. On the basis of GC/ECNI-MS ion chromatograms (m/z79 and 81), DPTE was the dominating Organobromine Compound in blubber and brain samples of hooded seals and harp seals (Phoca groenlandica) from the Barents and Greenland Seas. The concentrations of DPTE in blubber and brain were up to 470 and 340 microg/kg wet weight. Next to DPTE, the natural dibromo-trichloromonoterpene (MHC-1), the anthropogenic BDE 47 and BDE 99, as well as ATE, 3,5-dibromo-2-(2',4'-dibromo)-phenoxyanisole (6-MeO-BDE 47), 2-bromoallyl-2,4,6-tribromophenyl ether (BATE), and 4,6-dibromo-2-(2',4'-dibromo)-phenoxyanisole (2'-MeO-BDE 68) were present with decreasing relevance. BATE, which was detected for the first time in environmental samples, was synthesized from DPTE by E2 elimination. In brain samples of the harp seals, DPTE, ATE, and BATE were the most abundant Organobromine Compounds, whereas polybrominated diphenyl ethers (PBDEs) and MHC-1 were virtually absent. This indicated that DPTE, ATE, and BATE were able to penetrate the blood-brain barrier. The general co-occurrence of ATE and BATE in samples contaminated with DPTE support the hypothesis that these Compounds are biotransformation products of DPTE. Anaerobic transformation studies of DPTE with super-reduced corrinoids resulted in the formation of ATE. Furthermore, 2,4,6-tribromophenol (TBP) and two other unknown minor transformation products were detected.

Michael H.w. Lam - One of the best experts on this subject based on the ideXlab platform.

  • Organobromine Compound profiling in human adipose: Assessment of sources of bromophenol
    Environmental pollution (Barking Essex : 1987), 2015
    Co-Authors: Shixiong Gao, Yi Wan, Guomao Zheng, Kai Luo, Kurunthachalam Kannan, John P. Giesy, Michael H.w. Lam
    Abstract:

    Bromophenols (BRPs) have been widely detected in human tissues, however, relative proportions from natural products and/or anthropogenic flame retardants are not clear. 21 polybrominated diphenyl ethers (PBDEs), 15 MeO/OH-PBDEs, and 10 BRPs were simultaneously quantified in adipose collected from people from New York City, USA. An in vitro assay utilizing human liver microsomes was performed for detected predominant Organobromine. High concentrations of 2,4,6-triBRP and PBDEs were observed, and extremely low concentrations of naturally occurring MeO/OH-PBDEs were detected. Similar biotransformatioin rates of BRPs and MeO/OH-PBDEs indicated that the relative high concentration of 2,4,6-triBRP in humans was not of natural origin. Significant correlation observed between concentrations of 2,4,6-triBRP and BDE-209 suggested that the two chemicals may share a common source. Both 2,4,6-triBRP and BDE-209 were detected in commercial ABS resins, suggesting that plastic products made from ABS resins could be potential sources of co-exposure of the two Compounds for humans.

Hu Jianying - One of the best experts on this subject based on the ideXlab platform.

  • Organobromine Compound profiling in human adipose: Assessment of sources of bromophenol
    environmental pollution barking essex 1987, 2015
    Co-Authors: Gao Shixiong, Zheng Guomao, Luo Kai, Kannan Kurunthachalam, Giesy John P, Lam Michael H W, Hu Jianying
    Abstract:

    Bromophenols (BRPs) have been widely detected in human tissues, however, relative proportions from natural products and/or anthropogenic flame retardants are not clear. 21 polybrominated diphenyl ethers (PBDEs), 15 MeO/OH-PBDEs, and 10 BRPs were simultaneously quantified in adipose collected from people from New York City, USA. An in?vitro assay utilizing human liver microsomes was performed for detected predominant Organobromine. High concentrations of 2,4,6-triBRP and PBDEs were observed, and extremely low concentrations of naturally occurring MeO/OH-PBDEs were detected. Similar biotransformatioin rates of BRPs and MeO/OH-PBDEs indicated that the relative high concentration of 2,4,6-triBRP in humans was not of natural origin. Significant correlation observed between concentrations of 2,4,6-triBRP and BDE-209 suggested that the two chemicals may share a common source. Both 2,4,6-triBRP and BDE-209 were detected in commercial ABS resins, suggesting that plastic products made from ABS resins could be potential sources of co-exposure of the two Compounds for humans.Copyright ? 2015 Elsevier Ltd. All rights reserved.SCI(E)EIPubMed0ARTICLEwany@urban.pku.edu.cn81-8920