A study by a team of Harvard University researchers says current approaches to cleaning up contamination from PFAS-based firefighting foam, known as aqueous-film forming foam (AFFF), at Defense Department (DOD) sites fail to target precursor chemicals that could continue to produce regulated PFAS for centuries, adding to questions about the pace of DOD’s efforts. “The estimated PFAS reservoir in the vadose zone and modeled flux into groundwater suggest PFAS contamination above regulatory guidelines will persist for centuries without remediation,” the study says. The vadose zone is the Earth’s terrestrial subsurface that extends from the surface to the regional groundwater table.
The researchers contend this work highlights the importance of unregulated and often overlooked precursors for total PFAS exposures near AFFF releases and their role in sustaining high concentrations of regulated terminal PFSA, especially PFBS and PFHxS. “Little is known about population-wide exposure to precursors.”
May 15, 2023 | Environmental Science & Technology