On September 2, 2015, the U.S. Department of Health and Human Services' (HHS) Agency for Toxic Substances and Disease Registry (ATSDR), in accordance with guidelines developed by ATSDR and the U.S. Environmental Protection Agency (EPA), issued a proposed Toxicological Profile for Perfluoroalkyls for review and comment that included updated toxicological profiles for 13 perfluorinated chemicals, including two well-studied perfluorinated chemicals, perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA). ATSDR states in the Federal Register notice that comments can include additional information or reports on studies about the health effects of perfluoroalkyls and that it solicits any relevant, additional studies, particularly unpublished data, even though it did consider key studies for this substance during the profile development process. Further, ATSDR will evaluate the quality and relevance of such data or studies for possible inclusion into the Profile. Comments on the proposed Profile are due December 1, 2015. ATSDR plans to revise this Profile in response to public comments, and as additional data become available. The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) requires ATSDR to prepare toxicological profiles for each substance included on the priority list of hazardous substances, a list that identifies 275 hazardous substances that ATSDR (in cooperation with EPA) has determined pose the most significant potential threat to human health.
In July 2009, ATSDR announced the availability of a draft Toxicological Profile for perfluoroalkyls. The September 2, 2015, notice states that given the plethora of new data that have been published since 2009, and the resulting extensive revision to the Profile, the agency has determined that it would be in the best interest of public health to release the perfluoroalkyls Profile for another public comment period.
Proposed Toxicological Profile
Each ATSDR Toxicological Profile characterizes the toxicologic and adverse health effects information for the substance, identifying and reviewing the key literature that describes a substance's toxicologic properties, and providing information concerning levels of significant human exposure and, where known, significant health effects. Each profile includes:
An examination, summary, and interpretation of available toxicologic information and epidemiologic evaluations on a toxic substance to ascertain the levels of significant human exposure for the substance and the associated acute, subacute, and chronic health effects;
A determination of whether adequate information on the health effects of each substance is available or in the process of development to determine levels of exposure that present a significant risk to human health of acute, subacute, and chronic health effects; and
Where appropriate, identification of toxicologic testing needed to identify the types or levels of exposure that may present significant risk of adverse health effects in humans.
The draft Toxicological Profile discusses 13 perfluoroalkyl compounds: PFOS; PFOA; perfluorododecanoic acid (PFDoA); perfluorodecanoic acid (PFDeA); perfluorobutyric acid (PFBA); perfluoroheptanoic acid (PFHpA); perfluorononanoic acid (PFNA); perfluoroundecanoic acid (PFUA); perfluorohexane sulfonic acid (PFHxS); perfluorobutane sulfonic acid (PFBuS); perfluorooctane sulfonamide (PFOSA); 2-(N-methyl-perfluorooctane sulfonamide) acetic acid (Me-PFOSA-AcOH); and 2-(N-ethyl-perfluorooctane sulfonamide) acetic acid (Et-PFOSA-AcOH). Of specific note in this Profile is the proposal of minimal risk levels (MRL), which ATSDR describes as estimates of exposure levels posing minimal risk to humans, for the perfluoroalkyls PFOS and PFOA: intermediate-duration MRLs of 3x10-5 milligram PFOS per kilogram bodyweight per day (mg/kg/day) and 2x10-5 mg/kg/day for PFOA.
While ATSDR acknowledged in the Federal Register notice concerning the updated Profile that a "plethora of new data" has been published since 2009, ATSDR is only able to summarize existing data on health effects of inhalation, oral, and dermal exposure of humans and animals relevant to PFOS and PFOA. ATSDR states that for the remaining perfluoroalkyls, there is a "paucity of data for these chemicals, especially data in humans." Agencies initially focused on PFOS, leading to the 3M Company, the primary manufacturer of PFOS, completing a phase-out of its PFOS production in 2002. EPA then began to study the effects of PFOA, eventually resulting in the creation of the 2010/2015 PFOA Stewardship Program, widely regarded as a success. Under the Program, eight companies committed to achieve, no later than 2010, a 95 percent reduction in both facility emissions to all media of PFOA, precursor chemicals that can break down to PFOA and related higher homologue chemicals, and product content levels of these chemicals. The companies also agreed to work toward eliminating these chemicals from emissions and products by 2015. As noted in our more recent memoranda, EPA Announces Final Rule Concerning Perfluoroalkyl Sulfonates and Long-Chain Perfluoroalkyl Carboxylate Chemical Substances and TSCA: EPA Proposes a Significant New Use Rule That Would Close a Chapter on Perfluorinated Chemicals, EPA has shifted its regulatory scrutiny to the broader chemical class of perfluoroalkyls.
Other federal, state, and international agencies are also studying and seeking to restrict these chemicals. The National Toxicology Program's (NTP) Office of Health Assessment and Translation (OHAT) is evaluating the scientific evidence regarding the association between exposures to PFOS or PFOA and immunotoxicity. California's Office of Environmental Health Hazard Assessment (OEHHA) Developmental and Reproductive Toxicant Identification Committee (DARTIC) will discuss the prioritization of five chemicals, including PFOS and PFOA, at its November 9, 2015, meeting. Sweden has proposed PFNA be identified as a substance of very high concern (SVHC) under the European Union's (EU) Registration, Evaluation, Authorization and Restriction of Chemicals (REACH) regulation.
Regulated entities with interests in this class of chemicals may wish to pay close attention to the implications of the growing number of regulatory and scientific initiatives focusing on these chemicals. In addition to the obvious regulatory consequences of any forthcoming rulemaking, regulated entities need to be especially mindful of the value chain, liability, and commercial implications of these initiatives.