title: Anaerobic biotransformation of tetrabromobisphenol A, tetrachlorobisphenol A, and bisphenol A in estuarine sediments.
abstract: Biotransformation of the flame retardants tetrabromobisphenol A and tetrachlorobisphenol A, and their ultimate biodehalogenation product, bisphenol A, was examined in anoxic estuarine sediments. Dehalogenation of tetrabromobisphenol A and tetrachlorobisphenol A was examined under conditions promoting either methanogenesis or sulfate reduction as the primary terminal electron-accepting process. Complete dehalogenation of tetrabromobisphenol A to bisphenol A with no further degradation of bisphenol A, was observed under both methanogenic and sulfate-reducing conditions. Dehalogenation of tetrachlorobisphenol A under both methanogenic and sulfate-reducing conditions resulted in the accumulation of a persistent dichlorinated bisphenol A isomer, while no bisphenol A was formed. Co-amendment of sediment enrichments with either 2,6-dibromo- or 2,6-dichlorophenol did not affect the extent of dehalogenation as compared to sediments that were amended only with the flame retardants. Sediment cultures pre-acclimated on 2-bromophenol dehalogenated the flame retardants in a manner similar to that of fresh sediments. No loss of bisphenol A was observed in separate incubations within 162 days under conditions promoting either methanogenesis, sulfate-reduction, iron(III)-reduction, or nitrate-reduction. Furthermore, identical enrichments that readily degraded 4-hydroxybenzoate, a structural analogue of bisphenol A, did not exhibit bisphenol A degradation. The dehalogenation of tetrabromo- and tetrachlorobisphenol A and the potential for accumulation of bisphenol A in anoxic sediments is significant given the widespread use of these chemicals.
authors.affiliation: Department of Biochemistry and Microbiology, and Biotechnology Center for Agriculture and the Environment, Rutgers University, New Brunswick, New Jersey 08901, USA.
authors.forename: James W
authors.initials: JW
authors.lastname: Voordeckers
authors.forename: Donna E
authors.initials: DE
authors.lastname: Fennell
authors.forename: Kristi
authors.initials: K
authors.lastname: Jones
authors.forename: Max M
authors.initials: MM
authors.lastname: Häggblom
mesh_terms: D001421:Bacteria, Anaerobic / Q000502:physiology*; D001559:Benzhydryl Compounds; D001711:Biotransformation; D002733:Chlorophenols / Q000378:metabolism*; D004968:Estrogens, Non-Steroidal / Q000378:metabolism*; D005411:Flame Retardants / Q000378:metabolism*; D019015:Geologic Sediments / Q000737:chemistry / Q000382:microbiology; D010636:Phenols / Q000378:metabolism*; D011075:Polybrominated Biphenyls / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000378:metabolism; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D002733:Chlorophenols; D004968:Estrogens, Non-Steroidal; D005411:Flame Retardants; D010636:Phenols; D011075:Polybrominated Biphenyls; D014874:Water Pollutants, Chemical; C041181:tetrachlorodian; C020806:tetrabromobisphenol A; C006780:bisphenol A; D000098826:Bisphenol A Compounds