Perfluorinated Carbon Chain Length Drives Uptake of Diverse Per- and Polyfluoroalkyl Substances in Field-Deployed Passive Samplers

Per- and polyfluoroalkyl substances (PFAS) are a group of compounds of high concern due to their ubiquity, persistence, and adverse health impacts. With a diversity of chemical structures and properties, detection tools are needed to capture as many PFAS as possible. In this study, a microporous polyethylene tube (MPT) passive sampler was calibrated for 25 target compounds, 8 suspect PFAS and extractable organofluorine (EOF) during 1-2 week deployments in groundwater, a freshwater river, and estuary contaminated by aqueous film-forming foam (AFFF). Targeted analysis, suspect screening, and EOF were performed on passive and grab samples to derive sampling rates, <i>Rs</i>. Median measured and fluorine-normalized estimated EOF <i>Rs</i> in groundwater (7.1 vs 8.4 mL day^-1 respectively) and river water (55 vs 66 mL day^-1 respectively) were within 20% of each other. For suspect PFAS, <i>Rs</i> were similar to targeted PFAS of alike functional group chemistry and perfluorinated carbon chain length. For example, for 6:2 and 8:2 FTSAS-sulfoxide, estimated <i>R</i> _<i>s</i> were 1.8 and 6.0 mL day^-1, respectively, similar to <i>R</i> _<i>s</i> measured for 6:2 and 8:2 FTS of 2.2 and 6.3 mL day^-1. These results suggest targeted and suspect PFAS, and EOF, are predictably taken up by MPT samplers, expanding passive sampling capabilities.