Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences , Beijing 100101, China.
Environ Sci Technol. 2014;48(1):173-81. doi: 10.1021/es4044775. Epub 2013 Dec 16.
The use of snow and ice cores as recorders of environmental contamination is particularly relevant for per- and polyfluoroalky substances (PFASs) given their production history, differing source regions and varied mechanisms driving their global distribution. In a unique study perfluoroalkyl acids (PFAAs) were analyzed in dated snow-cores obtained from high mountain glaciers on the Tibetan Plateau (TP). One snow core was obtained from the Mt Muztagata glacier (accumulation period of 1980-1999), located in western Tibet and a second core from Mt. Zuoqiupo (accumulation period: 1996-2007) located in southeastern Tibet, with fresh surface snow collected near Lake Namco in 2010 (southern Tibet). The higher concentrations of ∑PFAAs were observed in the older Mt Muztagata core and dominated by perfluorooctanesulfonic acid (PFOS) (61.4-346 pg/L) and perfluorooctanoic acid (PFOA) (40.8-243 pg/L), whereas in the Mt Zuoqiupu core the concentrations were lower (e.g., PFOA: 37.8-183 pg/L) with PFOS below detection limits. These differences in PFAA concentrations and composition profile likely reflect the upwind sources affecting the respective sites (e.g., European/central Asian sources for Mt Muztagata and India sources for Mt Zuoqiupu). Perfluorobutanoic acid (PFBA) dominated the recent surface snowpack of Lake Namco which is mainly associated with India sources where the shorter chain volatile PFASs precursors predominate. The use of snow cores in different parts of Tibet provides useful recorders to examine the influence of different PFASs source regions and reflect changing PFAS production/use in the Northern Hemisphere.
利用冰雪芯作为环境污染的记录器，对于全氟和多氟烷基物质（PFASs）特别相关，因为它们的生产历史、不同的源区和不同的机制导致了它们在全球的分布。在一项独特的研究中，分析了青藏高原高山冰川获得的年代冰雪芯中的全氟烷基酸（PFAAs）。一个冰雪芯取自位于西藏西部的穆孜塔格冰川（积累期为 1980-1999 年），另一个冰雪芯取自位于西藏东南部的佐齐波山（积累期为 1996-2007 年），并在 2010 年在纳木错湖附近采集了新鲜的地表雪（西藏南部）。在较老的穆孜塔格冰川芯中观察到∑PFAAs 的浓度较高，以全氟辛烷磺酸（PFOS）（61.4-346 pg/L）和全氟辛酸（PFOA）（40.8-243 pg/L）为主，而在佐齐波山芯中浓度较低（例如，PFOA：37.8-183 pg/L），PFOS 低于检测限。这些 PFAA 浓度和组成特征的差异可能反映了影响各个地点的上风源（例如，穆孜塔格山的欧洲/中亚源和佐齐波山的印度源）。全氟丁酸（PFBA）在纳木错湖最近的地表雪中占主导地位，主要与印度源有关，其中短链挥发性 PFASs 前体占主导地位。在西藏不同地区使用冰雪芯提供了有用的记录器，可以用来考察不同 PFASs 源区的影响，并反映北半球 PFASs 生产/使用的变化。
