State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environment and Resources, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
Environ Sci Technol. 2011 Mar 15;45(6):2093-9. doi: 10.1021/es1033712. Epub 2011 Feb 22.
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.
六溴环十二烷（HBCDs）因其潜在的持久性、生物蓄积性和毒性而引起关注。本研究调查了来自中国南方两个电子废物回收区（清远、贵屿）和工业区的 90 个表层土壤中 HBCDs 的浓度、非对映异构体和对映体特异性分布以及质量清单。 两个周边电子废物回收区和工业区表层土壤中总 HBCDs 的平均浓度分别为 0.22-0.79 和 0.31-9.99ng/g dw。在清远的电子废物回收区发现了最高的总 HBCD 浓度（284ng/g dw），而随着与回收区的距离增加，总 HBCD 水平急剧下降，表明电子废物回收活动是 HBCDs 的重要来源。75 个土壤样本中的非对映异构体分布与商业产品不同。土壤中α-、β-和γ-HBCDs 的平均对映体分数值分别为 0.503（0.010）至 0.507（0.003）、0.494（0.003）至 0.506（0.009）和 0.502（0.003）至 0.511（0.006），表明三种非对映异构体没有立体选择性转化。HBCDs 的质量清单初步估计电子废物回收区和工业区的 HBCDs 分别为 3.42kg 和 1.84 吨。值得注意的是，本研究的非对映异构体和对映体分布未能明确区分异构化是在产品加工过程中还是在环境基质中发生的。需要进一步进行非生物和生物转化的实验室研究来澄清这个问题。
