Does regulating per‐ and polyfluoroalkyl substances represent a meaningful opportunity for health risk reduction?

Abstract

AbstractUS Environmental Protection Agency's drinking water contaminant regulations must meet a qualitative “meaningful opportunity” threshold in health risk reduction. Using our Relative Health Indicator (RHI) metric, we quantify the ranges of potential health risk reductions that could be achieved from state and federal per‐ and polyfluoroalkyl substances regulatory levels (proposed or finalized) and compare them with previous regulatory determinations of other contaminants to create a quantifiable, comparable scale of “meaningful opportunity” justifications. If perfluorooctanoic acid (PFOA) and perfluorooctyl sulfonate (PFOS) were present in 100% of water systems, contaminant concentrations of 227 ng/L PFOS and 2295 ng/L PFOA would be needed to exceed the minimum threshold of percent population*RHI (PopRHI) to justify “meaningful opportunity,” based on the current regulatory levels of uranium; these concentrations exceed any levels being proposed. Using this comparison metric, our results demonstrate that the regulatory levels for PFOA and PFOS alone will not achieve a national meaningful health risk reduction as compared with previously regulated contaminants.Article Impact StatementPlacing the 2021 USEPA PFAS positive RegDet in historical context, we evaluate "meaningful opportunity" for health risk reduction.