Mattila James M, Li Emily Y, Offenberg John H
Oak Ridge Institute for Science and Education, Office of Research and Development, U.S. Environmental Protection Agency, Durham, NC, USA.
Office of Research and Development, U.S. Environmental Protection Agency, Durham, NC, USA.
J Air Waste Manag Assoc. 2023 May;73(5):335-344. doi: 10.1080/10962247.2023.2174612.
Per- and polyfluoroalkyl substances (PFAS) are persistent environmental pollutants associated with negative health impacts. Assessments of tubing-related measurement bias for volatile PFAS are lacking, as gas-wall interactions with tubing can delay quantification of gas-phase analytes. We use online iodide chemical ionization mass spectrometry measurements to characterize tubing delays for three gas-phase oxygenated PFAS - 4:2 fluorotelomer alcohol (4:2 FTOH), perfluorobutanoic acid (PFBA), and hexafluoropropylene oxide dimer acid (HFPO-DA). Perfluoroalkoxy alkane and high-density polyethylene tubing yielded relatively short absorptive measurement delays, with no clear dependence on tubing temperature or sampled humidity. Sampling through stainless steel tubing led to prolonged measurement delays due to reversible adsorption of PFAS to the tubing surface, with strong dependence on tubing temperature and sample humidification. Silcosteel tubing afforded shorter measurement delays than stainless steel due to diminished surface adsorption of PFAS. Characterizing and mitigating these tubing delays is crucial for reliable quantification of airborne PFAS. Per- and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants. Many PFAS are sufficiently volatile to exist as airborne pollutants. Measurements and quantification of airborne PFAS can be biased from material-dependent gas-wall interactions with sampling inlet tubing. Thus, characterizing these gas-wall interactions are crucial for reliably investigating emissions, environmental transport, and fates of airborne PFAS.
全氟和多氟烷基物质（PFAS）是与负面健康影响相关的持久性环境污染物。目前缺乏对挥发性PFAS与管材相关的测量偏差的评估，因为与管材的气壁相互作用会延迟气相分析物的定量。我们使用在线碘化物化学电离质谱测量来表征三种气相含氧PFAS（4:2氟调聚物醇（4:2 FTOH）、全氟丁酸（PFBA）和六氟环氧丙烷二聚酸（HFPO-DA））的管材延迟。全氟烷氧基烷烃和高密度聚乙烯管材产生的吸收性测量延迟相对较短，且对管材温度或采样湿度没有明显依赖性。通过不锈钢管材采样会导致测量延迟延长，这是由于PFAS在管材表面的可逆吸附，且对管材温度和样品加湿有很强的依赖性。由于PFAS在表面的吸附减少，Silcosteel管材的测量延迟比不锈钢管材短。表征和减轻这些管材延迟对于可靠定量空气中的PFAS至关重要。全氟和多氟烷基物质（PFAS）是持久性环境污染物。许多PFAS具有足够的挥发性，可作为空气传播污染物存在。空气中PFAS的测量和定量可能会因与采样入口管材的材料相关气壁相互作用而产生偏差。因此，表征这些气壁相互作用对于可靠地研究空气中PFAS的排放、环境迁移和归宿至关重要。
