地球“三极”（南极，北极和青藏高原）的持久性有机污染物（POPs）来源及环境行为研究是环境科学领域持续关注的热点和重要前沿课题。以往研究认为大气长距离传输是POPs的主要来源途径，但青藏高原与极地区域环境特征差别明显，POPs赋存特征及具体来源亦有较大差异，开展极地与青藏高原POPs大气长距离传输特征对比研究对于深入理解长距离传输机制和POPs全球循环具有重要意义。本项目拟利用单体氯同位素分析（CSIA-Cl）技术从分子层面开展极地与青藏高原大气中典型POPs的环境行为对比研究，通过对极地和青藏高原大气样品中典型POPs如PCBs的CSIA-Cl分析，计算氯同位素比（δ37Cl值），揭示样品中单体氯同位素分馏效应，研究污染物在大气长距离传输过程中的变化及其指示意义，探讨区域特征（气象、海拔和植被等）对污染物迁移变化的影响，从而为揭示不同偏远区域POPs大气长距离传输机制提供直接的科学依据。

Study on the source identification and environmental behavior of persistent organic pollutants (POPs) in the Antarctica, Arctic and Tibetan Plateau have become a hot and important frontier topic in the field of environmental science. Previous studies have suggested that long-range atmospheric transport (LRAT) is the main pathway of POPs into those remote areas, but the environmental characteristics are obviously different between the Tibetan Plateau and the Polar Regions, and the occurrence and specific sources of POPs are also quite different in those areas. The comparison of the environmental behaviors of POPs between the Polar Regions and the Tibetan Plateau is of great significance for understanding the long-range transport mechanism and the global cycle of POPs. In this project, the atmospheric environmental behavior of typical POPs in Polar Regions and Tibetan Plateau will be comparatively studied at molecular level by using Compound-Specific Stable Chlorine Isotope Analysis (CSIA-Cl). The relative chlorine isotope ratio (δ37Cl) of typical POPs will be investigated by CSIA-Cl analysis in the atmospheric samples obtained from the Polar Regions and the Tibetan Plateau, and the fractionation effect of individual chlorine isotopes in the samples will be discussed. The changes of δ37Cl during LRAT and their implications will also be explored. The effects of regional characteristics (meteorology, altitude and vegetation, etc.) on pollutant transport will be further discussed, which may provide a direct scientific basis for revealing the long-range transport mechanism of POPs in different remote areas.