Occurrence and Fate of Per- and Polyfluoroalkyl Substances (PFAS) in Atmosphere: Size-Dependent Gas-Particle Partitioning, Precipitation Scavenging, and Amplification

作者：Xiaotong Li, Yuan Wang, Jiansheng Cui, Yali Shi, Yaqi Cai · 发表于：Environmental Science & Technology · 年份：2024 · DOI：10.1021/acs.est.4c00569 · 被引用次数：75 · 研究领域：Per- and polyfluoroalkyl substances research、Atmospheric chemistry and aerosols、Toxic Organic Pollutants Impact

The concerns about the fate of per- and polyfluoroalkyl substances (PFAS) in the atmosphere are continuously growing. In this study, size-fractionated particles, gas, and rainwater samples were simultaneously collected in Shijiazhuang, China, to investigate the multiphase distribution of PFAS in the atmosphere. Perfluoroalkyl carboxylic acids (PFCAs) dominated the total concentration of PFAS in atmospheric media. A strong positive relationship (0.79 < R 2 < 0.99) was observed between the concentration of PFCAs and organic matter fraction ( f OM ) in different particle size fractions, while no such relationship for perfluoroalkyl sulfonic acids (PFSAs) and f OM, suggesting f OM may be an important factor influencing the size-dependent distribution of PFCAs. Temperature played a key role in the gas-particle partitioning of PFAS, while it did not significantly affect their particle-size-dependent distribution. The associative concentration fluctuation of particle and particle-bound PFAS during precipitation suggested that precipitation scavenging was an important mechanism for the removal of PFAS from the atmosphere. Furthermore, temporary increases in atmospheric PFAS concentrations were observed during the precipitation. Fugacity ratios of PFAS in rainwater and gas phase (log f R / f G ranged between 2.0 and 6.6) indicated a strong trend for PFAS to diffuse from the rainwater to the gas phase during the precipitation, which may explain that the concentration of PFAS in the gas...