The Environmental Protection Agency said Wednesday that it plans to weaken limits on some “forever chemicals” in drinking water that were finalized last year, while maintaining standards for two common ones.

The Biden administration set the first federal drinking water limits for PFAS, or perfluoroalkyl and polyfluoroalkyl substances, finding they increased the risk of cardiovascular disease, certain cancers and babies being born with low birth weight. Those limits on PFAS, which are human-made and don’t easily break down in nature, were expected to reduce their levels for millions of people.

Limits on three types of PFAS, including what are known as GenX substances found in North Carolina, will be scrapped and reconsidered by the agency, as will a limit on a mixture of several types of PFAS.

The Biden administration’s rule also set standards for the two common types of PFAS, referred to as PFOA and PFOS, at 4 parts per trillion, effectively the lowest level at which they can be reliably detected. The EPA will keep those standards, but give utilities two extra years — until 2031 — to comply.

“We are on a path to uphold the agency’s nationwide standards to protect Americans from PFOA and PFOS in their water. At the same time, we will work to provide common-sense flexibility in the form of additional time for compliance,” said EPA Administrator Lee Zeldin.

The development was first reported by The Washington Post.

Large scale changes and utility pushback

It appears few utilities will be impacted by the withdrawal of limits for certain, newer types of PFAS. So far, sampling has found nearly 12% of U.S. water utilities are above the Biden administration’s limits. But most utilities face problems with PFOA or PFOS.

Health advocates praised Biden’s administration for the limits.

But water utilities complained, saying treatment systems are expensive and that customers will end up paying more. The utilities sued the EPA.

The EPA’s actions align with some arguments in the utilities’ lawsuit. They argued the EPA lacked authority to regulate a mixture of PFAS and said the agency didn’t properly support limits on several newer types of PFAS that the EPA now plans to rescind. They also sought the two-year extension.

Erik Olson, a senior strategist at the nonprofit Natural Resources Defense Council, said the move is illegal. The Safe Water Drinking Act gives the EPA authority to limit water contaminants, and it includes a provision meant to prevent new rules from being looser than previous ones.

“With a stroke of the pen, EPA is making a mockery of the Trump administration’s promise to deliver clean water for Americans,” Olson said.

President Donald Trump has sought fewer environmental rules and more oil and gas development. EPA Administrator Lee Zeldin has carried out that agenda by announcing massive regulatory rollbacks. The EPA plans to loosen regulations for greenhouse gas emissions, cleanup standards for coal plant waste and car emission limits, among many other clean air and water rules.

Zeldin’s history with PFAS is more nuanced; during his time as a New York congressman, he supported legislation to regulate forever chemicals.