title: Hexabromocyclododecanes in surface soils from E-waste recycling areas and industrial areas in South China: concentrations, diastereoisomer- and enantiomer-specific profiles, and inventory.
abstract: Hexabromocyclododecanes (HBCDs) are raising concern because of their potential persistence, bioaccumulation, and toxicity. In this study, we investigated the concentrations, diastereoisomer- and enantiomer-specific profiles, and mass inventories of HBCDs in 90 surface soils from two e-waste recycling areas (Qingyuan, Guiyu) and from industrial areas in South China. The mean concentrations of total HBCDs in the surface soils ranged from 0.22 to 0.79 and from 0.31 to 9.99 ng/g dw for two surrounding e-waste recycling sites and industrial areas, respectively. The highest total HBCD concentration (284 ng/g dw) was found at the e-waste recycling site in Qingyuan, while total HBCD levels fell dramatically with increasing distance from the recycling site, suggesting that the e-waste recycling activities were an important source of HBCDs. The diastereoisomer profiles in 75 of the 90 soil samples differed from those of the commercial products. The mean enantiomeric fraction values for α-, β-, and γ-HBCDs in soils ranged from 0.503(0.010) to 0.507(0.003), 0.494(0.003) to 0.506(0.009), and 0.502(0.003) to 0.511(0.006), respectively, suggesting that there was no stereoselective transformation of the three diastereoisomers. The mass inventories of HBCDs gave preliminarily estimates of 3.42 kg and 1.84 tonnes for the e-waste recycling areas and industrial areas, respectively. It is notable that the diasteroisomer and enantiomer profiles of this study failed to distinguish definitely that the isomeric transformation occurred during the product processing or in the environmental matrix. Further laboratory studies on abiotic and biotic transformation are needed to clarify this issue.
authors.affiliation: State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environment and Resources, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: Shutao
authors.initials: S
authors.lastname: Gao
authors.forename: Jingzhi
authors.initials: J
authors.lastname: Wang
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Yu
authors.forename: Qingrong
authors.initials: Q
authors.lastname: Guo
authors.forename: Guoying
authors.initials: G
authors.lastname: Sheng
authors.forename: Jiamo
authors.initials: J
authors.lastname: Fu
mesh_terms: D002681:China; D059029:Electronic Waste / Q000032:analysis*; D004784:Environmental Monitoring; D006842:Hydrocarbons, Brominated / Q000032:analysis* / Q000737:chemistry; D007220:Industrial Waste / Q000032:analysis; D012989:Soil Pollutants / Q000032:analysis* / Q000737:chemistry; D013237:Stereoisomerism; D018505:Waste Management
chemical_list: D006842:Hydrocarbons, Brominated; D007220:Industrial Waste; D012989:Soil Pollutants; C089796:hexabromocyclododecane