State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China.
Environmental Change Research Centre, University College London, Pearson Building, Gower Street, London, WC1E 6BT, UK.
Environ Geochem Health. 2018 Feb;40(1):303-312. doi: 10.1007/s10653-017-9908-7. Epub 2017 Jan 17.
Sediment cores from four lakes across the Tibetan Plateau were used as natural archives to study the time trends of organochlorine pesticides (OCPs). The total concentrations of dichlorodiphenyltrichloroethane (ΣDDT) and hexachlorocyclohexane isomers (ΣHCH) were in the range of 0.04-1.61 and 0.08-1.88 ng/g based on dry weight (dw), while the input fluxes were in the range of 0.3-236 and 0.7-295 pg/cm/y in the core sediments, respectively. The input fluxes of ΣDDT and ΣHCH generally peaked in sediment layers corresponding to the 1970s-1990s and peaked in top sediment layers. The ratio of α/γ-HCH decreased in the top layer sediments, implying that the contribution of lindane (pure γ-HCH) has been increasing in recent years. In addition, the ratio of o,p'-DDT/p,p'-DDT increased significantly over the last 15-20 years, suggesting that dicofol (characterized by high ratio of o,p'-DDT/p,p'-DDT about 7.0) has recently become a relatively more important source of DDT compared to technical DDT itself. The time trends of OCPs recorded in lake sediments examined the impact on such remote alpine regions by human activities.
利用青藏高原四个湖泊的沉积岩芯作为自然档案，研究了有机氯农药 (OCPs) 的时间变化趋势。基于干重 (dw)，二氯二苯三氯乙烷 (ΣDDT) 和六氯环己烷异构体 (ΣHCH) 的总浓度范围分别为 0.04-1.61 和 0.08-1.88ng/g，而在岩芯沉积物中的输入通量范围分别为 0.3-236 和 0.7-295pg/cm/y。ΣDDT 和 ΣHCH 的输入通量通常在对应于 20 世纪 70 年代至 90 年代的沉积层中达到峰值，并在顶层沉积物中达到峰值。α/γ-HCH 的比值在顶层沉积物中减少，这意味着近年来林丹（纯γ-HCH）的贡献一直在增加。此外，o,p'-DDT/p,p'-DDT 的比值在过去 15-20 年中显著增加，这表明三氯杀螨醇（以 o,p'-DDT/p,p'-DDT 的比值约 7.0 为特征）最近已成为 DDT 的一个相对更重要的来源，而不是技术 DDT 本身。湖泊沉积物中 OCPs 的时间变化趋势记录了人类活动对这些偏远高山地区的影响。
