References to EPAs lists of possible PFAS health effects based on current peer-reviewed studies and challenges with PFAS health effect evaluations can be found here:

Reference Dose is defined by the EPA as:

  • “In general, the RfD [Reference Dose] is an [oral or dermal] estimate (with uncertainty spanning perhaps an order of magnitude) of a daily exposure to the human population (including sensitive subgroups) that is likely to be without an appreciable risk of deleterious effects during a lifetime. The RfD is generally expressed in units of milligrams per kilogram of bodyweight per day (mg/kg/day).”

In 2016, the EPA applied the Wambaugh et al. (2013) model to derive a chronic oral reference doses (RfDs) for PFOA and PFOS (EPA 2016e, 2016f). This particular dose-response assessment for PFOA and PFOS resulted in the RfD of 2×10-5 mg/kg/day or 0.00002 mg/kg/day.

Frank Pagone, PhD, CIH

(773) 867-6011