Minsung Kim (Korea Basic Science Institute)

Kyoung-Soon Jang (Korea Basic Science Institute)

Minsung Kim (Korea Basic Science Institute)

Ji Yi Lee (Ewha Womans University)

Zhijun Wu (Peking University)

Kyoung-Soon Jang (Korea Basic Science Institute)

Per- and polyfluoroalkyl substances (PFASs) constitute a large family of synthetic chemicals comprising thousands of individual compounds. These substances are known for their persistence in the environment and their potential adverse health effects, including endocrine disruption, immunotoxicity, and carcinogenicity. Currently, most PFAS analyses focus on targeted analysis of a few standard compounds, which has limitations in identifying the vast array of numerous compounds. Non-targeted analysis using high-resolution mass spectrometry is essential to overcome these limitations. Additionally, non-targeted PFAS analysis of environmental media, such as the atmosphere, water, and soil, is sparse and necessary to determine the extent of PFAS components and their transformation products in the environment. In this study, we obtained a list of 9,004 suspect PFAS from the three largest PFAS databases (NIST, NORMAN, and EPA) and identified suspect PFAS present in airborne PM_2.5 samples collected from Seoul and Beijing during winter using ultra-high resolution 15 T FT-ICR mass spectrometry. Furthermore, we employed Kendrick analogues mass difference network (KAMDN) analysis to group the identified PFAS compounds. From the KAMDN analysis, we identified 46 PFAS groups, with the largest group derived from PFOA structures being observed in both cities. PFOS-related compounds were predominantly observed in Beijing, whereas unique long-chain PFAS species were identified in Seoul. These findings suggest that atmospheric PFAS exist in highly diverse forms, offering unique insights into the complex PFAS composition and expanding our understanding of PFAS chemistries in atmospheric environments. The identification of such diverse PFAS compounds underscores the necessity for comprehensive monitoring and regulatory measures to mitigate the potential health risks associated with PFAS exposure.