The director of the Agency for Toxic Substances and Disease Registry (ATSDR), Peter Breysse, continues to defend his agency's minimal risk levels (MRLs) for perfluorinated chemicals that were released in June 2018 as part of a draft toxicological profile. In response to questions posed at a recent Senate hearing, Breysse noted that ATSDR’s draft MRLs roughly corresponded to drinking water levels of 14 parts per trillion (ppt) for perfluorooctane sulfonate (PFOS) and 21 ppt for perfluorooctanoic acid (PFOA). Where these levels are exceeded, ATSDR has recommended that residents take steps to lower their exposures and contact state and local authorities. Breysse also recommended that residents consult with physicians and noted that ATSDR has information on its website for physicians to consult regarding exposure risks for these chemicals.
The drinking water levels referenced in the ATSDR toxicological profile (14 ppt for PFOS and 21 ppt for PFOA) correspond generally with regulatory standards implemented in several states, including New Jersey and Vermont, both of which have the lowest regulatory levels for these compounds in the United States. However, the ATSDR MRLs are much stricter than U. S. EPA’s drinking water advisory level of 70 ppt. In addition, many news outlets reported that U.S. EPA had sought to delay ATSDR’s issuance of its June 2018 toxicological profile. Perhaps coincidentally, at about the same time as ATSDR issued its draft report, U.S. EPA announced plans to begin to evaluate the need for a maximum contaminant level (MCL) for PFOA and PFOS.
Although ATSDR and U.S. EPA continue to work cooperatively (at least on paper) to address PFOA and PFOS at contaminated properties throughout the United States, it remains to be seen how well these agencies will cooperate in setting an MCL for these contaminants. The agencies' "cooperative" relationship may face choppy waters, especially in light of ATSDR's continued defense of its MRLs and U.S. EPA's skeptical view regarding same.