Air–water interfacial retention of poly- and perfluoroalkyl substances (PFASs) is increasingly recognized as an important environmental process. Herein, column transport experiments were used to measure air–water interfacial partitioning values for several perfluoroalkyl ethers and for PFASs derived from aqueous film-forming foam, while batch experiments were used to determine equilibrium K_ia data for compounds exhibiting evidence of rate-limited partitioning. Experimental results suggest a Freundlich isotherm best describes PFAS air–water partitioning at environmentally relevant concentrations (10¹–10⁶ ng/L). A multiparameter regression analysis for K_ia prediction was performed for the 15 PFASs for which equilibrium K_ia values were determined, assessing 246 possible combinations of 8 physicochemical and system properties. Quantitative structure–property relationships (QSPRs) based on three to four parameters provided predictions of high accuracy without model overparameterization. Two QSPRs (R² values of 0.92 and 0.83) were developed using an assumed average Freundlich n value of 0.65 and validated across a range of relevant concentrations for perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), and hexafluoropropylene oxide-dimer acid (i.e., GenX). A mass action model was further modified to account for the changing ionic strength on PFAS air–water interfacial sorption. The final result was two distinct QSPRs for estimating PFAS air–water interfacial partitioning across a range of aqueous concentrations and ionic strengths.

中文翻译：

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使用定量结构-性质关系 (QSPR) 预测 PFAS 的浓度和离子强度相关的空气-水界面分配参数

聚和全氟烷基物质 (PFAS) 的空气-水界面滞留越来越被认为是一个重要的环境过程。_{在此，柱传输实验用于测量几种全氟烷基醚和源自水性成膜泡沫的}PFAS 的空气-水界面分配值，而批次实验用于确定显示限速分配证据的化合物的平衡Kia数据. ^{实验结果表明，Freundlich 等温线最能描述 PFAS 在环境相关浓度 (10 1} –10 ⁶ ng/L)下的空气-水分配。K _ia的多参数回归分析对确定了平衡Kia值的 15 种 PFAS 进行了预测，评估了 8 种物理化学和系统特性的 246 种_{可能组合。}基于三到四个参数的定量结构-性质关系 (QSPR) 提供了高精度的预测，而无需模型过度参数化。使用假设的平均 Freundlich n开发了两个 QSPR（R ²值为 0.92 和 0.83）值为 0.65，并在全氟辛烷磺酸 (PFOS)、全氟辛酸 (PFOA) 和六氟环氧丙烷二聚酸（即 GenX）的一系列相关浓度范围内得到验证。进一步修改了质量作用模型，以解释 PFAS 空气-水界面吸附的离子强度变化。最终结果是两个不同的 QSPR，用于估计 PFAS 空气-水界面在一系列水溶液浓度和离子强度下的分配。