PDF(Pubmed)
Abstract：
Research on per- and polyfluoroalkyl substances (PFAS) frequently incorporates organofluorine measurements, particularly because they could support a class-based approach to regulation. However, standardized methods for organofluorine analysis in a broad suite of matrices are currently unavailable, including a method for extractable organofluorine (EOF) measured using combustion ion chromatography (CIC). Here, we report the results of an international interlaboratory comparison. Seven laboratories representing academia, government, and the private sector measured paired EOF and PFAS concentrations in groundwater and eel (Anguilla rostrata) from a site contaminated by aqueous film-forming foam. Among all laboratories, targeted PFAS could not explain all EOF in groundwater but accounted for most EOF in eel. EOF results from all laboratories for at least one replicate extract fell within one standard deviation of the interlaboratory mean for groundwater and five out of seven laboratories for eel. PFAS spike mixture recoveries for EOF measurements in groundwater and eel were close to the criterion (±30%) for standardized targeted PFAS methods. Instrumental operation of the CIC such as replicate sample injections was a major source of measurement uncertainty. Blank contamination and incomplete inorganic fluorine removal may introduce additional uncertainties. To elucidate the presence of unknown organofluorine using paired EOF and PFAS measurements, we recommend that analysts carefully consider confounding methodological uncertainties such as differences in precision between measurements, data processing steps such as blank subtraction and replicate analyses, and the relative recoveries of PFAS and other fluorine compounds.
摘要：
对全氟烷基和多氟烷基物质（PFAS）的研究经常结合有机氟的测量，特别是因为他们可以支持基于阶级的监管方法。然而,目前还没有在广泛的矩阵中进行有机氟分析的标准化方法，包括使用燃烧离子色谱法(CIC)测量的可萃取有机氟(EOF)的方法。这里,我们报告了国际实验室间比较的结果。代表学术界的七个实验室，政府,私营部门测量了受水性成膜泡沫污染的地点的地下水和鳗鱼（安圭拉rostrata）中的成对EOF和PFAS浓度。在所有实验室中，有针对性的PFAS不能解释地下水中的所有EOF，但解释了鳗鱼中的大部分EOF。来自所有实验室的至少一种重复提取物的EOF结果落在地下水的实验室间平均值的一个标准偏差之内，而鳗鱼的七个实验室中有五个。在地下水和鳗鱼中进行EOF测量的PFAS加标混合物回收率接近标准化目标PFAS方法的标准（±30％）。CIC的仪器操作，例如重复进样，是测量不确定性的主要来源。空白污染和不完全的无机氟去除可能引入额外的不确定性。为了使用配对的EOF和PFAS测量来阐明未知有机氟的存在，我们建议分析师仔细考虑混杂的方法学不确定性，如测量之间的精度差异，数据处理步骤，如空白减法和重复分析，以及PFAS和其他氟化合物的相对回收率。
