Perfluoroalkyl acids (PFAAs) mostly exist as ionic compounds that are of major concern because of their accumulative behavior. The discussion about their risk is ongoing considering the increasing production of structurally similar alternatives. We conducted model calculations based on equilibrium distribution coefficients that allow studying the distribution of PFAAs and their alternatives in various mammalian organs through comparison to empirical measurements in humans and rats. The calculations rely on experimentally determined distribution coefficients of a series of PFAAs and 4 of their alternatives to physiological matrices such as structural proteins, storage lipids, membrane lipids, albumin, and fatty acid binding protein (FABP). The relative sorption capacities in each organ were calculated from the combination of distribution coefficients and physiological data. The calculated distribution of PFAAs and alternatives within the organs showed that albumin and membrane lipids and, to a lesser extent, structural proteins have the highest relative sorption capacities for the compounds. Sorption to FABP is only relevant in the distribution of short‐chain PFAAs. Storage lipids play a minor role in the distribution of all studied compounds. Our calculated distribution of PFAAs was evaluated by comparison to reported PFAA concentrations in various organs. Environ Toxicol Chem 2021;40:910–920. © 2020 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

中文翻译：

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估计全氟烷基酸及其 4 种替代品在哺乳动物中的平衡分布

全氟烷基酸 (PFAA) 主要作为离子化合物存在，由于它们的累积行为而备受关注。考虑到结构相似替代品的产量不断增加，有关其风险的讨论仍在进行中。我们基于平衡分布系数进行了模型计算，通过与人类和大鼠的经验测量进行比较，可以研究 PFAA 及其替代品在各种哺乳动物器官中的分布。计算依赖于实验确定的一系列 PFAA 的分配系数，以及它们的 4 种生理基质替代品，如结构蛋白、储存脂质、膜脂质、白蛋白和脂肪酸结合蛋白 (FABP)。从分布系数和生理数据的组合计算每个器官的相对吸附能力。PFAAs 和替代品在器官内的计算分布表明，白蛋白和膜脂以及在较小程度上的结构蛋白对这些化合物具有最高的相对吸附能力。对 FABP 的吸附仅与短链 PFAA 的分布有关。储存脂质在所有研究化合物的分布中起次要作用。我们计算出的 PFAA 分布是通过与各种器官中报告的 PFAA 浓度进行比较来评估的。结构蛋白对化合物具有最高的相对吸附能力。对 FABP 的吸附仅与短链 PFAA 的分布有关。储存脂质在所有研究化合物的分布中起次要作用。我们计算出的 PFAA 分布是通过与各种器官中报告的 PFAA 浓度进行比较来评估的。结构蛋白对化合物具有最高的相对吸附能力。对 FABP 的吸附仅与短链 PFAA 的分布有关。储存脂质在所有研究化合物的分布中起次要作用。我们计算出的 PFAA 分布是通过与各种器官中报告的 PFAA 浓度进行比较来评估的。环境毒理学化学2021；40：910-920。© 2020 作者。环境毒理学和化学由 Wiley Periodicals LLC 代表 SETAC 出版。