EPA Sets First Federal Limits on Dangerous ‘Forever Chemicals’ in Drinking Water

Public water systems will have to test water and reduce levels of six types of PFAS if they aren’t in compliance with the new rule

Rows of grape vines in front of a building
A vineyard in central California that had been irrigated with PFAS-contaminated well water from firefighting foam used for years at a nearby airport. Brian van der Brug / Los Angeles Times via Getty Images

For the first time, the U.S. federal government has set national limits on levels of harmful “forever chemicals” in drinking water.

The chemicals, called per- and polyfluoroalkyl substances, or PFAS, have been widely used in consumer products—though they take a long time to break down in the environment and have been linked to a number of health problems. The new rule will reduce PFAS exposure for an estimated 100 million people and could prevent thousands of deaths, the Environmental Protection Agency (EPA) says in a statement.

“We’ve been waiting for federal regulation of these chemicals for a long time,” Linda Birnbaum, a microbiologist at Duke University who studies the health effects of exposure to environmental chemicals, tells the Washington Post’s Teddy Amenabar. “We know that drinking water is a very significant source of the contamination.”

The new limits are “the most important step we’ve taken to improve the safety of our tap water in a generation” and “the single most important step we’ve taken to address PFAS, ever,” Scott Faber, senior vice president of governmental affairs for the Environmental Working Group, which advocates for regulation of drinking water pollutants, says to NBC News’ Aria Bendix.

PFAS have been used since the 1940s in hundreds of products, including stain- and water-resistant fabrics, cleaning products, cookware, food packaging, paints, firefighting foams and more.

Some of the most common types of PFAS are no longer in use, according to Michael Phillis of the Associated Press (AP). But due to their strong carbon-fluorine bonds, PFAS take a very long time to break down and are found in the air, water and soil, as well as the blood of animals and people around the world. They’ve also been identified in popular makeup products and in locally caught freshwater fish.

Research has linked PFAS exposure to cancer, heart and liver problems, and immune and developmental damage in children, per the EPA.

“It’s that accumulation that’s the problem,” Scott Belcher, who studies PFAS toxicity at North Carolina State University, tells the AP. “Even tiny, tiny, tiny amounts each time you take a drink of water over your lifetime is going to keep adding up, leading to the health effects.”

The EPA first proposed the recently announced limits in March 2023. The new rule sets a limit for two types of PFAS, called PFOA and PFOS, at 4 parts per trillion. For the four other regulated compounds—PFNA, PFHxS, PFBS and “GenX chemicals”—it sets limits on mixtures of them. Individually, it also caps PFNA, PFHxS and GenX chemicals at 10 parts per trillion.

Some states already have their own PFAS limits, but these will be the first on the federal level, according to NPR’s Pien Huang.

Research suggests any level of exposure to PFOA and PFOS can bring a risk of negative health impacts—and the EPA has previously recommended even lower limits on these chemicals in water. In 2022, the agency said PFOA and PFOS should ideally be capped at 0.004 and 0.02 parts per trillion, respectively. But the new limit of 4 parts per trillion reflects the lowest level that can feasibly be detected and enforced.

Public water systems have until 2027 to complete initial monitoring and must inform the public of the determined PFAS levels. If the levels exceed the EPA’s limits, utilities have to reduce them by 2029.

The new rule applies to 66,000 public water systems, and the EPA estimates that between 6 and 10 percent will need to reduce PFAS levels to meet the new standards. EPA tests over the past year revealed that around 16 percent of utilities had levels of at least one of the two most limited chemicals, PFOA and PFOS, above the new limits, per the AP.

Compliance will cost public water systems $1.5 billion per year, according to the EPA, but it will also prevent tens of thousands of serious illnesses. The American Water Works Association, an industry group, says in a statement that it estimates the cost could be “more than three times higher than the agency’s calculations,” according to the Washington Post.

The EPA is making $1 billion in grant funding available for states, territories and private well owners to conduct testing and treatment. The funds come from the federal government’s 2021 infrastructure law, which set aside $9 billion for addressing drinking water contaminants and an additional $12 billion for drinking water infrastructure improvements.

In total, there are thousands of types of PFAS. The new rule only addresses six, but the additional compliance efforts taken to target these six contaminants will probably “significantly reduce” other types of PFAS in drinking water as well, David Andrews, a senior scientist at the Environmental Working Group, tells the Washington Post.

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