Attorney General Bonta Joins Multistate Letter Opposing EPA’s Proposal to Weaken Forever Chemical Regulation

OAKLAND - California Attorney General Rob Bonta today joined a multistate comment letter opposing the U.S. Environmental Protection Agency's (EPA) proposal to rescind regulation of certain per-and polyfluoroalkyl substances (PFAS), also known as "forever chemicals," in drinking water. The proposal would reduce public health protections, lengthen the EPA's process for adopting drinking water regulations, and allow the EPA to undo current drinking water regulations in violation of the Safe Drinking Water Act (SDWA) and the Administrative Procedure Act (APA).

"With this proposal, the Trump Administration's EPA is choosing once again to strip away public health protections that keep our communities safe," said Attorney General Bonta. "Exposure to PFAS harms public health - our communities cannot afford to be exposed to these forever chemicals. Weakening these regulations is more than a violation of the law - it's a violation of every Americans' right to know the water coming out of their faucets is safe to drink."

PFAS are a class of chemicals that have waterproof, non-stick, and stain-resistant properties. They have been used in many consumer and industrial products, including food packaging, non-stick cookware, clothing, carpets, paints, cleaning products, batteries, microchips, machinery, and firefighting foam. Studies have thus far linked PFAS to numerous adverse health effects, such as cancer (including breast and testicular cancer), developmental delays, infertility, lower bone density, immune system damage, endocrine system harms, liver disease, heart disease, and high cholesterol. PFAS are long-lasting and highly mobile, and they have contaminated many waters and soils, particularly in and around airports, military facilities, PFAS manufacturing plants, landfills, and agricultural lands. This environmental contamination increases the risk of exposure to PFAS, especially through drinking water supplies.

The proposed regulation concerns "GenX" PFAS compounds, which were developed as a replacement once older types of PFAS were discovered to be toxic, but which were later determined to be toxic as well. The regulation EPA proposes to rescind, adopted in 2024, sets drinking water limits for three "GenX" PFAS compounds individually and in combination with each other or a fourth GenX compound, using a formula or "index." Hence, the comment refers to these compounds as "Index PFAS." In adopting the 2024 regulation, EPA made the legally-required determination, based the best available science, that the Index PFAS may have an adverse effect on the health of persons, occur in public water systems with a frequency and at levels of public health concern, and that regulation presents a meaningful opportunity for health risk reduction for persons served by public water systems. EPA's proposal to rescind the 2024 regulation does not question these findings. Instead, it argues that its 2024 rulemaking failed to follow the procedures prescribed by the SDWA for adopting the regulation.

Enacted in 1974, the SDWA authorizes the EPA to adopt regulations limiting contaminants in drinking water supplied by public water systems and sets forth a process for doing so. As part of that process, the EPA must make a determination whether to regulate a contaminant. If the EPA makes a determination to regulate a contaminant, it must propose and adopt a maximum contaminant level goal and national primary drinking water regulation (Standards) for the contaminant. The SDWA also contains an "anti-backsliding" mandate, which provides that any revision to the Standards "shall maintain, or provide for greater, protection of the health of persons."

In March 2023, the EPA jointly published preliminary regulatory determinations and proposed Standards for certain "GenX" PFAS compounds. Attorney General Bonta joined a multistate comment letter in support of the proposed GenX Standards. In April 2024, the EPA adopted final regulatory determinations and Standards for GenX PFAS compounds. However, on May 20, 2026, the EPA published a proposal to rescind these regulatory determinations and Standards for GenX PFAS compounds, claiming that its earlier interpretation that the SDWA authorizes publishing proposed Standards concurrently with preliminary regulatory determinations was incorrect.

In the comment letter, the multistate coalition explains that the EPA's proposal to rescind the 2024 regulation is in violation of the law because:

• The SDWA's anti-backsliding provision bars the EPA from rescinding the Goals and Standards previously set in its 2024 regulations.
• The SDWA prohibits the EPA from rescinding its determination to regulate the GenX/Index PFAS.
• The EPA failed to provide a reasoned justification for changing its interpretation of the statute, as required under the APA.
• The EPA's proposed Rescission Rule is arbitrary and capricious.
• The EPA would fail to comply with the APA by not considering alternatives to wholesale rescission of the Final Rule.

Attorney General Bonta is a national leader in the fight to protect against the harms of PFAS contamination. He is prosecuting claims against major PFAS manufacturers such as 3M, DuPont, Chemours, and Corteva, and successfully co-led multistate coalitions in advocating for improvements to proposed class action settlements between public water systems and 3M and DuPont. That work can be found here, here, and here. Separately, he has supported stronger federal PFAS regulations under the Safe Drinking Water Act and the Resource Conservation and Recovery Act, and has taken measures to protect Californians from exposures to PFAS through food packaging and cookware.

In filing the comment letter, Attorney General Bonta joins the attorneys general of Arizona, Colorado, Connecticut, Delaware, the District of Columbia, Hawaii, Illinois, Maine, Maryland, Massachusetts, Minnesota, North Carolina, New Jersey, New York, Rhode Island, Oregon, Washington, and Wisconsin.