The U.S. EPA has announced plans to revoke the maximum contaminant levels for PFNA, PFHxS, GenX, and PFBS pending regulatory reform. Only the limits for PFOA and PFOS will remain in effect, with the compliance deadline pushed from 2029 to 2031.
Forever chemicals, Trump to weaken EPA safety limits
They’re called forever chemicals because, unlike other toxic substances, they don’t break down. Once released, they persist in the environment and living organisms for decades. These compounds, known as PFAS (per- and polyfluoroalkyl substances), have gained notoriety in recent years due to their widespread presence. It’s troubling, then, to learn they are now the target of deregulatory efforts by the Trump administration.
According to recent disclosures from the U.S. Environmental Protection Agency (EPA), a set of regulations addressing certain PFAS compounds is on the verge of being repealed, effectively undoing one of the last public health protections enacted in recent years.
Drinking water limits under threat
In April 2024, under the Biden administration, the EPA finalized new maximum contaminant levels for six types of PFAS in drinking water. These limits targeted perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), GenX, PFBS, PFNA, and PFHxS. For four of them, the agency also introduced a hazard index, a tool used to assess cumulative risk from chemical mixtures.
Just a year later, the U.S. is shifting course. The current administration aims to introduce more flexibility in how PFAS regulations are applied.
EPA policies on PFAS under Trump
“The effort to protect Americans from PFAS in drinking water began under the first Trump administration and will continue under my leadership,” said EPA Administrator Lee Zeldin. “We are on track to meet the agency’s national standards for protecting Americans from PFOA and PFOS. At the same time, we will ensure commonsense flexibility, including extended compliance timelines. This will support water systems across the country, including small systems in rural communities, in addressing these contaminants.”
The new EPA approach would retain MCLs only for PFOA and PFOS, the two most well-known PFAS chemicals, and push the compliance deadline from 2029 to 2031.
Limits on PFNA, PFHxS, GenX, and PFBS would be scrapped for now, pending future regulation.
To offset the rollback, the EPA has pledged to expand its field efforts through the PFAS OUT program, aiming to connect with public water utilities in need of upgrades to address PFAS contamination.
Environmental groups raise red flags
“Dozens of peer-reviewed studies that the EPA relied on to establish these historic standards have repeatedly shown that PFAS are toxic even at incredibly low levels. This isn’t politics, it’s science,” said Ken Cook, president of the nonprofit Environmental Working Group (EWG). “The PFAS contamination crisis goes far beyond just two chemicals, and there’s growing evidence that other PFAS in drinking water are also harmful. Removing all PFAS from tap water must be an urgent public health priority.”
EPA’s plan to rescind four science-based MCLs could also conflict with the Safe Drinking Water Act’s anti-backsliding clause, which mandates that any revision to a drinking water standard must “maintain or provide greater human health protection.”
