School of Civil and Environmental Engineering, Water Research Centre, University of New South Wales, Sydney, NSW 2052, Australia.
School of Civil Engineering and Environmental Science, University of Oklahoma, Norman, OK 73019, USA.
Sci Total Environ. 2021 Apr 10;764:142882. doi: 10.1016/j.scitotenv.2020.142882. Epub 2020 Oct 14.
The factors controlling per- and polyfluoroalkyl substances (PFAS) environmental fate remains the subject of considerable debate and study. As surfactants, PFAS readily partition to interfaces, a property that controls their transport and fate. A group contribution model is developed to predict the extent to which PFAS partitions to the air-water interface. Langmuir adsorption and Szyszkowski equation parameters were fitted to literature air-water surface tension data for a range of PFAS and conventional hydrocarbon surfactants. This approach enabled the prediction of the impact of the hydrophilic head group, and other molecular components, on PFAS interfacial partitioning in instances when PFAS data are unavailable but analogous hydrocarbon surfactant data are available. The model was extended to predict a range of parameters (i.e., solubility, critical micelle concentration (CMC), K, K and K) that are used to predict PFAS environmental fate, including long-range PFAS transport and in multimedia models. Model predictions were consistent with laboratory and field derived parameters reported in the literature. Additionally, the proposed model can predict the impact of pH and speciation on the extent of PFAS interfacial partitioning, a potentially important feature for understanding the behaviors of some ionizable PFAS, such as fluorinated carboxylic acids. The proposed model provides a conceptually straightforward method to predict a wide range of environmental fate parameters for a wide range of PFAS. As such, the model is a powerful tool that can be used to determine parameters needed to predict PFAS environmental fate.
控制全氟和多氟烷基物质 (PFAS) 环境命运的因素仍然是相当有争议和研究的主题。作为表面活性剂，PFAS 很容易分配到界面，这种性质控制着它们的迁移和命运。本文开发了一种基团贡献模型来预测 PFAS 分配到气-水界面的程度。朗缪尔吸附和 Szyszkowski 方程参数拟合了一系列 PFAS 和常规碳氢化合物表面活性剂的文献气-水表面张力数据。这种方法使我们能够预测在没有 PFAS 数据但有类似碳氢化合物表面活性剂数据可用的情况下，亲水头基团和其他分子成分对 PFAS 界面分配的影响。该模型被扩展到预测一系列参数（即溶解度、临界胶束浓度 (CMC)、K、K 和 K），这些参数用于预测 PFAS 的环境命运，包括长距离 PFAS 迁移和多介质模型。模型预测与文献中报道的实验室和现场得出的参数一致。此外，所提出的模型可以预测 pH 和形态对 PFAS 界面分配程度的影响，这对于理解某些可电离 PFAS（如氟化羧酸）的行为是一个潜在的重要特征。该模型提供了一种概念上简单的方法来预测广泛的 PFAS 的各种环境命运参数。因此，该模型是一个强大的工具，可以用来确定预测 PFAS 环境命运所需的参数。
