State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; School of Environment, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 310024, China.
State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
J Environ Sci (China). 2020 Dec;98:31-38. doi: 10.1016/j.jes.2020.04.030. Epub 2020 Jun 12.
High-altitude lake sediment can be used as a natural archive to reconstruct the history of pollutants. In this work, the temporal distribution of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were determined using a high-resolution gas chromatography coupled with high-resolution mass spectrometer (HRGC/HRMS) in an alpine lake sediment core collected from the southern Tibetan Plateau (TP) to examine whether the expected decreasing trends due to the implementation of the international Conventions could be observed. The concentrations of PCBs and PBDEs in the sediment core were in the range of 11.8-142 pg/g dw and ND-457 pg/g dw, and their fluxes were in the range of 2.51-31.7 ng/(m·yr) and ND-43.2 ng/(m·yr), respectively. The prevalence of low-chlorinated (tri-CB) PCBs and low-brominated (tri- to tetra-) PBDEs in most sections of the sediment profiles was observed, suggesting that the light molecular weight PCBs and PBDEs have most likely reached lake sediments by long-range atmospheric transport from distant sources. Despite the restrictions on their applications, the sediment records for the concentrations and fluxes showed no corresponding decreasing trend with restrictions for PCBs, which suggested that these POPs (e.g., PCBs) were still emitted to the environment owing to the influence of primary or secondary emissions. To our knowledge, this is the first report on input history of atmospheric PCBs and PBDEs recorded in TP Lake sediment.
高山湖泊沉积物可用作重建污染物历史的天然档案。在这项工作中，我们使用高分辨率气相色谱-高分辨率质谱（HRGC/HRMS）在青藏高原南部采集的高山湖泊沉积物芯中测定了多氯联苯（PCBs）和多溴二苯醚（PBDEs）的时间分布，以检验是否可以观察到由于实施国际公约而预期的减少趋势。沉积物芯中 PCBs 和 PBDEs 的浓度范围分别为 11.8-142 pg/g dw 和 ND-457 pg/g dw，其通量范围分别为 2.51-31.7 ng/（m·yr）和 ND-43.2 ng/（m·yr）。在沉积物剖面的大多数部分都观察到低氯（三氯）PCBs 和低溴（三至四溴）PBDEs 的存在，这表明轻分子量的 PCBs 和 PBDEs 很可能通过远距离大气传输从遥远的来源到达湖泊沉积物。尽管对其应用存在限制，但沉积物中浓度和通量的记录并没有表现出与 PCBs 限制相对应的减少趋势，这表明这些持久性有机污染物（如 PCBs）仍因原生或次生排放而排放到环境中。据我们所知，这是首次在青藏高原湖泊沉积物中记录大气 PCBs 和 PBDEs 输入历史的报告。
