For the first time, the Environmental Protection Agency has established national limits for six types of perfluoroalkyl and polyfluoroalkyl substances in drinking water.
The substances, known by the initialism PFAS, are nicknamed “forever chemicals” because they barely degrade and are nearly impossible to destroy, so they can linger permanently in air, water and soil.
As a class of chemicals, PFAS have been associated with a higher risk of certain cancers, heart disease, high cholesterol, thyroid disease, low birth weight and reproductive issues, including decreased fertility.
Most people in the U.S. have PFAS in their blood, according to the Department of Health and Human Services.
The EPA announced Wednesday that levels of PFOA and PFOS — two types of PFAS commonly used in nonstick or stain-resistant products such as food packaging and firefighting foam — can’t exceed 4 parts per trillion in public drinking water.
Three additional PFAS chemicals will be restricted to 10 parts per trillion. They are PFNA and PFHxS — older versions of PFAS — and GenX chemicals, a newer generation of chemicals created as a replacement for PFOA.
PFOA and PFOS are the most widely used and studied types of PFAS, according to the EPA. Companies started making them in the 1940s, but the substances were largely phased out of U.S. chemical and product manufacturing in the mid-2000s. However, they persist in the environment and have mostly been replaced by newer types of chemicals within the same class.
The EPA’s new limit reflects the lowest levels of PFOA and PFOS that laboratories can reasonably detect and public water systems can effectively treat. But, according to the agency, water systems should aim to eliminate the chemicals, because there is no safe level of exposure.
Eleven states already have regulatory standards for PFAS in drinking water. The EPA estimated that 6% to 10% of the country’s public water systems — 4,100 to 6,700 systems in total — will need to make changes to meet the new federal limits.
“One hundred million people will be healthier and safer because of this action,” EPA Administrator Michael Regan said Tuesday on a media call, referring to the number of people served by the water systems that will need upgrades.
As of Wednesday, public water systems that don’t monitor for PFAS have three years to start. If they detect PFAS at levels above the EPA limits, they will have two more years to purchase and install new technologies to reduce PFAS in their drinking water.
The EPA estimates that the new limits will prevent thousands of deaths and tens of thousands of serious illnesses.
One of the biggest health concerns associated with PFOA is an increased risk of kidney cancer. Exposure to high levels of PFOS has also been associated with an increased risk of liver cancer.
GenX chemicals have been shown in animal studies to damage the liver, kidneys and immune system, as well as liver and pancreatic tumors. According to studies in rodents, PFNA exposure could lead to developmental issues and PFHxS may disrupt the thyroid system.
The EPA also set a limit Wednesday for mixtures of at least two of the following chemicals: PFNA, PFHxS, PFBS and GenX. Public water systems can use an equation provided by the EPA to determine whether the cumulative concentrations of the chemicals exceed the agency’s threshold.
The EPA proposed limits to PFAS in drinking water last year. After it reviewed public comments, it made the limits official Wednesday.
“This is a huge, historic public health win,” said Scott Faber, senior vice president of government affairs for the Environmental Working Group, an activist group that advocates for stricter regulations of drinking water pollutants.
Faber called the new EPA limits “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.”
Jamie DeWitt, director of the Environmental Health Sciences Center at Oregon State University, said that although the new limits don’t end the problem of PFAS in drinking water, they represent significant progress.
“This is going to give people in contaminated communities at least a sense that the federal government cares about them and cares about their exposure, because I think many people living in PFAS-impacted communities have not felt heard,” she said.
The EPA said Wednesday that $1 billion in funding is newly available to help states and territories implement PFAS testing and treatment at public water systems and to help owners of private wells do the same. The funding comes from the federal infrastructure law passed in 2021, which set aside $9 billion to address PFAS and other contaminants in water. The money will be distributed as grants.
Some public water systems have also sued companies that manufacture or previously manufactured PFAS, aiming to hold them accountable for the costs of testing and filtering for PFAS. One such lawsuit resulted in a $1.18 billion settlement last year for 300 drinking water providers nationwide. Another lawsuit awarded $10.5 billion to $12.5 billion, depending on the level of contamination found, to public water systems across the country through 2036.
The most common way to remove PFAS from water is through an activated carbon filter, which traps the chemicals as water passes through. Other options include reverse osmosis or ion exchange resins, which act like tiny magnets that attract PFAS chemicals.
But even once water is treated for PFAS, it can take a while to see positive impacts, said Anna Reade, director of PFAS advocacy at the National Resources Defense Council, a nonprofit environmental advocacy group.
“For most of these six chemicals, it’s between two to eight years for the amount in our bodies to decrease by half. So we’re looking at years before we see some substantial decreases in our exposure over time,” she said.
The EPA’s new drinking water limits apply to only a small fraction of the more than 12,000 types of PFAS, so activists are still concerned about overall exposure.
“This is not the final step,” Reade said. “We still have a lot of other PFAS to worry about.”