Per- and Polyfluoroalkyl Substances (PFAS) in Cloud Water and Precipitation Samples from Whiteface Mountain, NY

Per- and polyfluoroalkyl substances (PFAS) are a group of nearly 15,000 synthetic chemicals that are classified as persistent pollutants due to their resistance to environmental degradation. Research on the environmental cycling of PFAS is of great importance, as many of these compounds have been linked to negative human and ecological health impacts. An increasing number of these compounds have been found in notable concentrations within various terrestrial aquatic systems (e.g., groundwater, lakes, and streams), with more recent research also documenting PFAS contamination of the atmosphere (e.g., in rainwater) across the globe. It is now recognized that atmospheric cycling is a major contributor to PFAS global dissemination and deposition. To advance our understanding of atmospheric loading, transport, and processing of PFAS, wet deposition (WD) samples obtained from National Atmospheric Deposition Program (NADP) samplers at the base of Whiteface Mountain (WFM), NY and cloud water (CW) samples collected at the WFM summit, were analyzed for a broad range of PFAS from several major PFAS classes (including PFBA, PFPeA, PFHxA, PFHpA, PFOA, PFNA, PFOS, HFPO-DA, and several sulfonamides). Fifty precipitation samples (September 2020 - January 2022) were analyzed and 30 archived CW samples were selected (July through September 2018-2021) for this preliminary study. The CW samples represent the range of air mass trajectories that influence the summit as determined by HYSPLIT cluster analysis of back-trajectories during CW collection periods 2014-2021 (n = 804). The sum of measured PFAS concentrations in more than 50% of the CW samples tested exceeded 4ppt. Here we present a detailed comparison of PFAS concentrations measured in CW and WD samples from WFM, and discuss future plans for this ongoing research.