title: Intrinsic debromination potential of polybrominated diphenyl ethers in different sediment slurries.
abstract: The fate of BDE-153 (BDE = brominated diphenyl ethers) in different mangrove, fresh water pond, and marine subsurface sediments collected from Hong Kong SAR was investigated. Under anaerobic conditions, all sediments showed good intrinsic abilities to reductively debrominate BDE-153, producing debromination products ranging from hexa- to mono-BDEs in 90 days. The half-lives of BDE-153 in eight different sediments varied from 7.6 to 165 days, with higher debromination in mangrove than marine and fresh water pond sediments. All sediments exhibited the preference in removing the bromine in para, followed by meta, and the lowest in ortho positions; however, fresh water pond sediments had relatively higher fractions of meta (BDE-99) and ortho substitution (BDE-118) of the three penta-BDE products. Mai Po mangrove and fresh water pond subsurface sediments were also capable of debrominating BDE-47 in 90 days of anaerobic incubation with half-lives of 76.2 and 56.9 days, respectively; but not BDE-209. BDE-47, -153, and -209 in Mai Po surface sediment were not transformed under 30 day aerobic incubation. This study demonstrated that the microbial-mediated debromination of BDE-47 and -153 occurred in natural subsurface sediments under anaerobic conditions although the rates and pathways varied among the sediment types.
authors.affiliation: Department of Biology and Chemistry, City University of Hong Kong , Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region, People's Republic of China.
authors.forename: Haowen
authors.initials: H
authors.lastname: Zhu
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Wang
authors.forename: Tiangang
authors.initials: T
authors.lastname: Luan
authors.forename: Nora F Y
authors.initials: NF
authors.lastname: Tam
mesh_terms: D000332:Aerobiosis; D000693:Anaerobiosis; D001966:Bromine / Q000737:chemistry*; D005618:Fresh Water / Q000737:chemistry; D008401:Gas Chromatography-Mass Spectrometry; D019015:Geologic Sediments / Q000032:analysis*; D006207:Half-Life; D055768:Halogenated Diphenyl Ethers / Q000737:chemistry*; D006723:Hong Kong; D012623:Seawater / Q000737:chemistry
chemical_list: D055768:Halogenated Diphenyl Ethers; D001966:Bromine