Detection and Quantitation of Per- and Polyfluoroalkyl Substances in North Carolina Sea Foam and the Corresponding Sea Water

Per- and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants found in various matrices, including water and sea foam. This study utilized both quantitative and nontargeted analysis (NTA) to investigate PFAS contamination in sea foam, bulk water, and blank samples collected from the Atlantic coast near Wilmington, North Carolina. Previous work has suggested PFAS can accumulate at higher concentrations in sea foam than the bulk water. High-resolution mass spectrometry (HRMS) was employed to identify and quantify PFAS, with strict quality control measures applied to confirm results. Quantitative analysis detected up to 42 PFAS compounds, with particularly high concentrations in condensed sea foam samples, highlighting their role in accumulating PFAS. In one foam sample, PFOS, was observed at ca. 8,000,000 ng/L (ppt) whereas, PFO5DoA, a compound predominantly found in North Carolina, was detected at levels exceeding 20,000 ng/L in some samples. Notably, emerging and regionally relevant PFAS─including unsaturated perfluorooctanesulfonic acid (UPFOS), hexafluoropropylene oxide tetramer acid (HFPO-TeA), and 3-oxaperfluorononanesulfonic acid (F53)─were identified through nontargeted analysis. Comparisons between bulk water and sea foam samples revealed distinct PFAS concentration patterns, and significantly higher concentrations in the sea foam. The study underscores the need for continued monitoring of PFAS in coastal environments to assess potential human and ecological exposure risks.