EPA’s Proposed Changes to Federal PFAS Drinking Water Regulations
The U.S. Environmental Protection Agency (EPA) has announced a new proposed rule that could significantly reshape federal drinking water standards for several PFAS chemicals.
The proposal, announced May 18, 2026, focuses on regulations adopted in 2024 under the Biden Administration. Those earlier rules established legally enforceable Maximum Contaminant Levels (MCLs) for several PFAS compounds in public drinking water systems. Utilities across the country were required to comply with those standards by April 2029.
Now, the EPA says portions of those regulations may not have followed the procedural requirements outlined in the Safe Drinking Water Act.
What the EPA Is Reconsidering
The agency is proposing to rescind regulations involving:
- Perfluorohexane sulfonic acid (PFHxS)
- Perfluorononanoic acid (PFNA)
- Hexafluoropropylene oxide dimer acid and its ammonium salt(HFPO-DA), commonly called GenX chemicals
- Hazard Index mixtures involving those chemicals and perfluorobutane sulfonic acid (PFBS)
At the same time, the EPA is separately proposing changes related to PFOA and PFOS, two of the most widely discussed PFAS compounds. Those proposed changes would extend compliance deadlines through a federal exemption framework for public water systems.
The agency says the goal is to ensure future regulations fully comply with the Safe Drinking Water Act process before they are finalized and enforced.
Public Comment Period Open
The proposed rescission rule and the compliance extension rule for PFOA and PFOS will share a combined hearing process scheduled for July 7, 2026. Members of the public may provide verbal comments during the hearing, but advance registration is required. The deadline to pre-register to speak is July 1, 2026. Click HERE to register for the virtual hearing (it’s free).
The EPA is accepting written comments on the proposed rules through July 20, 2026. Comments can be submitted through the federal rulemaking portal at regulations.gov under the specific dockets. See our Instructions to Submit Written Comments to the EPA Dockets for guidance on accessing the online submission form.
| Rescission of Regulatory Determinations | Extending the Compliance Deadline |
|---|---|
| Docket ID: EPA-HQ-OW-2025-0654 | Docket ID: EPA-HQ-OW-2025-1742 |
| Proposed Rule: 2026-10085 (91 FR 29413) | Proposed Rule: 2026-10086 (91 FR 29425) |
| EPA Website: Proposed PFAS Rescission Rule | EPA Website: Proposed PFOA and PFOS Compliance Extension Rule |
Why PFAS Continue to Draw Attention
PFAS, often referred to as “forever chemicals,” are a large group of synthetic chemicals that have been used in industrial processes and consumer products for decades. They are valued for their resistance to heat, water, and oil, but that same durability has created long-term environmental and health related concerns.
According to the EPA:
- PFAS break down very slowly over time
- They are commonly found in water, soil, air, fish, and food products
- Many PFAS compounds have been detected in the blood of humans and animals worldwide
- Scientific research has linked exposure to some PFAS chemicals with potential health risks including:
- Reproductive effects such as decreased fertility or increased high blood pressure in pregnant women.
- Developmental effects or delays in children, including low birth weight, accelerated puberty, bone variations, or behavioral changes.
- Increased risk of some cancers, including prostate, kidney, and testicular cancers.
- Reduced ability of the body’s immune system to fight infections, including reduced vaccine response.
- Interference with the body’s natural hormones.
- Increased cholesterol levels and/or risk of obesity.
Researchers and regulators continue to face challenges studying PFAS because thousands of different compounds exist, many of which remain poorly understood.
What Comes Next
If finalized, the EPA’s proposed actions could alter how federal drinking water standards for several PFAS compounds are enforced moving forward. Public water systems, environmental groups, industry stakeholders, and state regulators are expected to closely monitor the outcome of the rulemaking process.
The proposal also signals a broader debate over how aggressively PFAS should be regulated and how federal agencies should balance public health concerns with statutory and procedural requirements under federal law.
