Department of Chemistry, Memorial University, St. John's, NL, Canada A1B 3X7.
Aquatic Contaminants Research Division, Environment and Climate Change Canada, Burlington, ON, Canada L7S 1A1.
Environ Sci Process Impacts. 2017 Jan 25;19(1):22-30. doi: 10.1039/c6em00593d.
To improve understanding of long-range transport of perfluoroalkyl substances to the High Arctic, samples were collected from a snow pit on the Devon Ice Cap in spring 2008. Snow was analyzed for perfluoroalkyl acids (PFAAs), including perfluoroalkyl carboxylic acids (PFCAs) and perfluoroalkyl sulfonic acids (PFSAs), as well as perfluorooctane sulfonamide (FOSA). PFAAs were detected in all samples dated from 1993 to 2007. PFAA fluxes ranged from <1 to hundreds of ng per m per year. Flux ratios of even-odd PFCA homologues were mostly between 0.5 and 2, corresponding to molar ratios expected from atmospheric oxidation of fluorotelomer compounds. Concentrations of perfluorobutanoic acid (PFBA) were much higher than other PFCAs, suggesting PFBA loading on the Devon Ice Cap is influenced by additional sources, such as the oxidation of heat transfer fluids. All PFCA fluxes increased with time, while PFSA fluxes generally decreased with time. No correlations were observed between PFAAs and the marine aerosol tracer, sodium. Perfluoro-4-ethylcyclohexanesulfonate (PFECHS) was detected for the first time in an atmospherically - derived sample, and its presence may be attributed to aircraft hydraulic system leakage. Observations of PFAAs from these samples provide further evidence that atmospheric oxidation of volatile precursors is an important source of PFAAs to the Arctic environment.
为了增进对全氟烷基物质向北极地区长距离迁移的了解，2008 年春季在德文冰盖上采集了一个雪坑样本。对雪样进行了全氟烷基酸（PFAAs）分析，包括全氟烷基羧酸（PFCAs）和全氟烷基磺酸（PFSAs）以及全氟辛烷磺酰胺（FOSA）。1993 年至 2007 年的所有样本中均检测到了 PFAAs。PFAAs 的通量范围为<1 至数百 ng/m/年。偶数-奇数 PFCAs 同系物的通量比大多在 0.5 至 2 之间，这与氟调聚物化合物在大气中氧化产生的摩尔比相对应。全氟丁酸（PFBA）的浓度远高于其他 PFCAs，表明德文冰盖上的 PFBA 负荷受到其他来源的影响，例如传热流体的氧化。所有 PFCAs 的通量随时间增加，而 PFSAs 的通量通常随时间减少。未观察到 PFAAs 与海洋气溶胶示踪剂（钠）之间存在相关性。首次在大气衍生样品中检测到全氟-4-乙基环己烷磺酸（PFECHS），其存在可能归因于飞机液压系统泄漏。这些样本中 PFAAs 的观测结果进一步证明了大气中挥发性前体的氧化是 PFAAs 向北极环境输入的一个重要来源。
