On Tuesday, the Environmental Protection Agency announced that drinking water regulations have begun the process of imposing strict limits on the levels of some members of the PFAS (perfluoroalkyl and polyfluoroalkyl substances) chemical family. PFAS are widely used and associated with a wide range of health problems. Their chemical stability has also earned them the term “eternal chemicals”. Officials are now seeking public feedback on a rule that means there are too many detectable levels of the two chemicals.
PFAS are a large group of chemicals used in a wide range of products such as nonstick cooking pots, fire resistant foam and waterproof clothing. They are useful mainly due to their water-repellent, hydrophobic properties. Their properties also tend to prevent them from participating in chemical processes that could otherwise degrade them, so contamination problems tend to persist long after PFAS use. , immune dysfunction, altered hormonal signaling, liver damage, and reproductive problems.
Back in 2021, the Biden administration announced it would launch a research and regulatory program focused on PFAS, and last year issued interim guidance on acceptable levels. Today’s announcement marks the start of a formal rulemaking process confirming the development of legally binding limits. This process will include EPA publishing the proposed rule to give the public and stakeholders an opportunity to provide feedback. Once that feedback has been processed, the formal rules will be published.
The most surprising part of this proposal is that two chemicals, perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), are set at 4 ppt, the current limit of detectability. In other words, if there is any indication that a chemical is present, it exceeds the legal limit. (These are both acidic hydrocarbons with all hydrogens replaced by fluorine.)
A second set of related chemicals (PFNA, PFHX, PFBS, and GenX chemicals) are regulated together. Each has a limit set on the acceptable level. Each level is calculated as a percentage of its limit and the percentages are added together. If it exceeds 100%, regulation will start.
As part of previous efforts, the EPA is already providing grants to help water utilities set up to test these chemicals. It also said that various means of extracting these chemicals from water are now available.
