title: Tetrabromobisphenol-A and hexabromocyclododecane in birds from an e-waste region in South China: influence of diet on diastereoisomer- and enantiomer-specific distribution and trophodynamics.
abstract: Tetrabromobisphenol-A (TBBPA) and three diastereomers of hexabromocyclododecane (HBCD) were examined in the muscles of six bird species and their diet collected from an e-waste recycling region (Qingyuan) in South China. Stable isotope ratios (delta15N and delta13C) were analyzed to measure the diet source and trophic levels (TLs) of the birds. The median TBBPA and HBCD concentrations in the birds ranged from 28 to 173 and not detectable to 1995 ng/g lipid weight, respectively. The diastereoisomeric pattern shows the predominance of alpha-HBCD in birds feeding in an aquatic environment and that of gamma-HBCD in birds feeding in a terrestrial environment, whereas no clear preference for alpha isomer or gamma isomer was found in birds that inhabited freshwater wetland. A significant positive correlation between delta13C and percentage of alpha-HBCD was observed, indicating the importance of diet exposure pathways in the determination of HBCD diastereoisomer pattern. The enantiomer fractions (EFs) for alpha-HBCD differed substantially between aquatic and terrestrial bird species with a significant enrichment of (+) alpha-HBCD enantiomer for aquatic birds and a preferential enrichment of (-) alpha-HBCD enantiomer for terrestrial birds. The similarity in diastereoisomer profiles of HBCD and the EFs of alpha-HBCD between prey (fish) and predator (Chinese pond heron) also suggested that dietary exposure is an important contributor for the observed diastereoisomer- and enantiomer-specific distribution of HBCD in birds. Trophic magnification was observed for alpha-HBCD and TBBPA as concentrations increased with the TLs of the birds defined by delta15N, but only alpha-HBCD showed a strong positive relationship (p=0.001). The biomagnification factors for alpha- and gamma-HBCD and TBBPA were calculated based on individual predator/prey feeding relationships for two species.
authors.affiliation: State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: Ming-Jing
authors.initials: MJ
authors.lastname: He
authors.forename: Xiao-Jun
authors.initials: XJ
authors.lastname: Luo
authors.forename: Le-Huan
authors.initials: LH
authors.lastname: Yu
authors.forename: Juan
authors.initials: J
authors.lastname: Liu
authors.forename: Xiu-Lan
authors.initials: XL
authors.lastname: Zhang
authors.forename: She-Jun
authors.initials: SJ
authors.lastname: Chen
authors.forename: Da
authors.initials: D
authors.lastname: Chen
authors.forename: Bi-Xian
authors.initials: BX
authors.lastname: Mai
mesh_terms: D000818:Animals; D001717:Birds / Q000378:metabolism*; D002681:China; D004032:Diet; D055615:Electrical Equipment and Supplies; D004784:Environmental Monitoring; D004785:Environmental Pollutants / Q000737:chemistry / Q000378:metabolism*; D020387:Food Chain; D006842:Hydrocarbons, Brominated / Q000737:chemistry / Q000378:metabolism*; D009132:Muscles / Q000378:metabolism; D011075:Polybrominated Biphenyls / Q000737:chemistry / Q000378:metabolism*; D013237:Stereoisomerism; D014866:Waste Products
chemical_list: D004785:Environmental Pollutants; D006842:Hydrocarbons, Brominated; D011075:Polybrominated Biphenyls; D014866:Waste Products; C089796:hexabromocyclododecane; C020806:tetrabromobisphenol A