You are here:
Transformation of per-and polyfluoroalkyl substances during onsite septic system treatment
Citation:
Glassmeyer, S., S. Wigginton, B. Baumgaertel, G. Heufelder, M. Mills, S. Corum, A. Brown, M. Modiri, D. Kolpin, D. Tettenhorst, J. Story, I. Dombroski, T. McCobb, L. Erban, P. Bradley, AND K. Smalling. Transformation of per-and polyfluoroalkyl substances during onsite septic system treatment. Decentralized Wastewater MOU Full Partner Call, Cincinnati, OH, March 12, 2025.
Impact/Purpose:
Research demonstrates PFAS precursors present in household wastewater convert to measured PFAS during onsite septic treatment
Description:
Approximately 25% of homes in the United States treat their wastewater using onsite septic systems rather than centralized wastewater treatment plants. Innovative/alternative (I/A) septic systems have been designed to reduce the amount of nutrients released into the environment. Recent work in partnership with the Massachusetts Alternative Septic System Test Center (MASSTC) has explored contaminants of emerging concern (CECs) concentration changes within two traditional and three I/A onsite septic systems. Preliminary results indicated that while many pharmaceuticals and other CEC parent compounds were partially-to-totally removed in both traditional and I/A systems, the concentrations of the monitored per- and polyfluoroalkyl substances (PFAS) increased in the effluents relative to the influent wastewater. Additional sampling events included a wider suite of targeted PFAS, as well as methods to measure total oxidizable precursors (TOP) and adsorbable organic fluorine (AOF). The use of multiple methods provides greater insight to the fate of PFAS during treatment than any one individual method. The expanded testing verified that the increased concentrations post-treatment were not due to matrix interference, but conversion of unidentified PFAS precursors to the PFAS intermediates/end products that were measured by the targeted analytical methods (i.e., we documented transformation of the precursors, not the addition of more PFAS).