This study investigated the occurrence, stereoisomeric behavior, and potential sources of hexabromocyclododecanes (HBCDs) in topsoil and terrestrial vegetation from Svalbard and ocean sediment samples from Kongsfjorden, an open fjord on the west coast of Spitsbergen. The mean levels of total concentrations (ΣHBCDs) were comparable to those in other remote regions and were lower than those in source regions. Elevated proportions of α-HBCD with an average of 41% in the terrestrial samples and 25% in ocean sediments compared to those in commercial products (10–13% for α-HBCD) were observed, implying isomerization from γ- to α-HBCD in the Arctic environment. In addition, the extensive deviations of enantiomeric fractions (EFs) from the racemic values reflected the effect of biotransformation on HBCD accumulation. Linear correlation analysis, redundancy analysis, and back-trajectory were combined to infer possible HBCD sources, and the results showed the important role of global production and long-range environmental transport (LRET) for the entry of HBCDs into the Arctic at an early stage. To the best of our knowledge, this study represents the first report on the diastereoisomer- and enantiomer-specific profiles of HBCDs in the Arctic terrestrial environment and sheds light on the transport pathways and environmental fate for more effective risk management related to HBCDs in remote regions.

中文翻译：

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北极斯瓦尔巴群岛土壤、植物和沉积物中的六溴环十二烷：水平、异构体概况、手性特征和潜在来源


本研究调查了斯瓦尔巴特群岛表土和陆地植被以及斯匹次卑尔根岛西海岸开放峡湾 Kongsfjorden 的海洋沉积物样本中六溴环十二烷 (HBCD) 的存在、立体异构行为和潜在来源。总浓度（ΣHBCD）的平均水平与其他偏远地区相当，但低于来源地区。与商业产品（α-HBCD 为 10-13%）相比，观察到陆地样品中 α-HBCD 的比例平均为 41%，海洋沉积物中为 25%，这意味着从 γ- 异构化为 α-HBCD在北极环境中。此外，对映体分数 (EF) 与外消旋值的广泛偏差反映了生物转化对 HBCD 积累的影响。结合线性相关分析、冗余分析和回溯轨迹推断六溴环十二烷可能的来源，结果表明全球生产和远程环境迁移（LRET）对于六溴环十二烷早期进入北极具有重要作用。据我们所知，这项研究是关于北极陆地环境中六溴环十二烷非对映异构体和对映体特异性概况的第一份报告，并揭示了六溴环十二烷的运输途径和环境命运，以便在偏远地区更有效地管理与六溴环十二烷相关的风险。