When the first federal rules limiting a handful of so-called “forever chemicals” in drinking water were adopted in 2024, advocates who had long fought for stricter regulations on harmful PFAS chemicals celebrated.
The limits set by the U.S. Environmental Protection Agency two years ago were lower than the limits New Hampshire regulators set in 2019. They only applied to six of the roughly 15,000 PFAS chemicals. But state officials worried about the costs and feasibility of implementing stricter limits on a substance that has made its way into every part of life, and the bodies of essentially all Americans.
The Biden administration argued the benefits – longer, healthier lives for people across the country – outweighed the costs. States were expected to adopt those new standards by the end of this month.
But in September, the EPA under the Trump administration asked states to delay the adoption of those standards, after they had announced months earlier they would roll back limits on four of the newly-regulated PFAS chemicals.
The proposed changes exclude newer PFAS chemicals that are still being used from regulation and only limit older chemicals that have already been phased out.
“It’s kind of giving industry a way out,” said Julia Varshavsky, a public health and engineering professor at Northeastern University.
Listen to our reporting on PFAS contamination in Merrimack here.
While the administration also extended deadlines for public water systems to comply with those changes, state officials say they haven’t seen drafts of the federal government's proposed changes to the 2024 regulations.
“We have drafted PFAS regulations. They are done and ready to go,” said Brandon Kernen, the head of New Hampshire’s Drinking Water and Groundwater Bureau.
The state’s draft rules mimic what they believe the federal government’s final rules will be, but New Hampshire won’t adopt finalized rules until they know where those federal regulations stand.
How is New Hampshire moving forward?
New Hampshire applied for an extension on formally adopting the rules, but the state is currently operating under an agreement with EPA that allows state officials to administer the federal PFAS standards. Those require public water systems to meet limits for PFOA, PFOS, PFHxS, PFNA, HPFO-DA (also known as Gen-X), and PFBS by 2029.
Right now, administering those rules involves working with local water systems to complete water testing that is due by 2027, Kernen said. That’s not a huge change, because New Hampshire is ahead of many other states on water testing efforts.
But to meet the current requirement, water systems must test for chemicals that the Trump administration has said they may no longer regulate.
“It leaves us in a quandary,” Kernen said. “Do we tell our systems to collect this data, when EPA says it has no intention of keeping those regulations?”
Another consideration, according to state officials, is that the two regulations that the Trump administration is keeping for legacy PFAS chemicals – PFOA and PFOS – seem to weed out the newer contaminants like GenX, which are still being used in the U.S. and are connected to harmful health effects.
Kernen says based on tens of thousands of test results from water systems and private wells, any violations of PFOA or PFOS limits should still catch those newer forever chemicals, even if federal regulators rescind limits for them.
The stricter federal standards for PFOA and PFOS will require about 200 water systems in New Hampshire to install treatment systems or combine with other communities to reduce levels – tripling the number of water systems that must take action on PFAS chemicals.
Abby Thompson Fopiano, the chair of the New Hampshire Water Works Association, said water systems across the state are rushing to keep up with the federal requirements – even without knowing what the final version will be.
Small water systems, often operated by homeowners associations, may be hit hardest, if they haven’t been saving up to install new treatment equipment. Larger water systems will also need to figure out how to pay for upgrades. The Trump Administration’s proposal to get rid of some PFAS regulations will make the transition easier, Thompson Fopiano said.
“The treatment systems that we're putting in treat for all the compounds, so it's not as if we aren't going to be treating for PFAS as a whole. It's just that monitoring for compliance and sampling will be easier to follow,” she said.
In Merrimack, which has experienced long-running PFAS contamination issues, the water department is treating the water so that no detectable PFAS chemicals come through at all, said Don Provencher, the chair of the Merrimack Village District board. When they see even small amounts of a PFAS chemical break through their filters, they switch out filters.
“That first breakthrough has never been PFOA or PFOS. It's typically PFBA or PFPeA, which are two shorter chain unregulated compounds,” he said. PFPeA is used as part of grease-proof coatings on food packaging. PFBA is a breakdown product from other PFAS chemicals, and was previously used to create photographic film.
Provencher said that approach is the most protective of public health, but the strategy is costly. Settlements with companies like 3M, DuPont and Saint-Gobain that created or used PFAS chemicals have covered some treatment costs, but the funding won’t last as long as the chemicals they left behind.
“You're going to be paying to treat this stuff and to change the filters out for hundreds and hundreds and hundreds, if not a thousand years,” he said.
Impacts of changing regulations
There are more than 15,000 PFAS chemicals. The 2024 limits applied to six of them, and if the Trump administration changes those rules, only two will be regulated.
Advocates and some scientists have long argued for regulating PFAS as a class of chemicals, said Varshavsky, the researcher from Northeastern.
“Industry can kind of get away with continuing to pollute and continuing to use the chemicals in different kinds of products when we don't restrict or regulate those,” she said. “It basically provides an opportunity to have this problem of regrettable substitution.”
In an email statement, an EPA spokesperson said protecting Americans from exposure to PFAS in water is a priority for the Trump administration, and noted that the agency launched a new effort to reach out to communities with PFOA and PFOS issues to provide resources on how to address those contaminants.
The EPA said their plan to rescind some of the PFAS regulations was related to their assessment that the Biden administration’s limits didn’t adhere to the Safe Drinking Water Act.
“Once this action to correct the error is finalized, the agency will follow through on its commitment to regulate additional PFAS in drinking water. It’s important to note that while EPA cannot pre-determine the outcome, it is possible that the result could be more stringent requirements,” the spokesperson said.
But the federal office responsible for conducting rigorous assessments of substances, the Office of Research and Development, was dismantled last year and replaced with a new Office of Applied Science and Environmental Solutions. The U.S. government has lost more than 10,000 scientists since the beginning of 2025, including more than 400 at the EPA.
Varshavsky says the Integrated Risk Information System, which was housed within the dismantled Office of Research and Development and was responsible for characterizing health hazards of chemicals, was a particular loss.
“Removing that I think just gives the process more bias, and the bias is likely to fall in the direction of those who have a financial stake in making the chemicals,” she said.
When asked how the changes would affect the agency’s ability to regulate chemicals, an EPA spokesperson said the EPA's Office of Groundwater and Drinking Water has organized scientists from within the organization into a new science division.
EPA officials announced new members of the agency’s board responsible for providing scientific advice last week. They include representatives from Chemours, which took over DuPont’s PFAS operations in 2015, and from other firms like Dow Chemical and Corteva Agriscience.
Ultimately, Varshavsky said, even with federal regulations on legacy PFAS chemicals, newer, shorter-chain PFAS chemicals are still a concern.
“We are not really solving the problem,” she said. “We're creating more of a problem, or just kind of kicking the can down the road to deal with later.”
