By Joe Cotruvo(1), Susan Goldhaber(2), and Andrew Cohen, Issue Paper in Groundwater, February 20, 2023.

 

1. Former Director, USEPA Drinking Water Standards Division.

2. Former Toxicologist, USEPA

 

 

Per- and polyfluoroalkyl substances (PFAS) are persistent and widely distributed in the environment from commercial products and waste process residues, including in surface waters usually at low parts per trillion (ppt) levels. Groundwaters near contaminated locations can have higher parts per trillion or parts per billion (ppb) concentrations. In June, 2022, Interim EPA Drinking Water Health Advisories (HAs) for perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) that were originally 70 ppt were reduced to 0.004 and 0.020 ppt, respectively. The minimum reporting levels (MRLs) for PFOA and PFOS are currently 4 ppt. The scientific basis for these very low and unmeasurable HA values for PFOA and PFOS is debatable and up to about five orders of magnitude below many other worldwide national recommendations (e.g., Australia, UK, Canada), which are in the range of 100 ppt and above.

 

DOWNLOAD PUBLICATION

 

 

Related Webinar Presentation (1 minute summary):