EPA Sets Limits on ‘Forever Chemicals’ in Tap Water—Here’s How That Will Affect You

For the first time, the Environmental Protection Agency has limited the amount of PFAS, known as “forever chemicals,” in drinking water. 

PFAS stands for perfluoroalkyl and polyfluoroalkyl substances. They are a group of 15,000 chemicals that have been in use for the past 70 years, found in everything from firefighting foam to yogurt containers.¹ These chemicals break down and can wind up in the air and much of our drinking water, and a growing body of research suggests some types can harm human health. 

The new rule will reduce PFAS exposure for about 100 million people and prevent thousands of serious illnesses and deaths, the EPA said in a statement.²

“This will make a significant difference in how people are exposed to PFAS,” John Rumpler, JD, the clean water director and senior attorney for Environment America, told Health. “I am much more alarmed about these forever chemicals in our drinking water than just [their] presence in our products.”

How Do Forever Chemicals Affect Human Health?

Scientists are just beginning to understand how and to what extent forever chemicals harm human health. So far, the strongest link is between PFAS and interference in the production of hormones, which are critical for normal bodily function and play a vital role in fertility.

For a lab study published in Environment International, researchers looked at the effect of one of the most studied classes of PFAS chemicals on mouse ovarian cells. They found that a type called perfluorooctanoic acid (PFOA) disrupted embryonic development.³ 

Additionally, the authors of a review published in Human Reproductive Update concluded that there was limited evidence directly linking PFAS to reproductive issues but that numerous epidemiologic studies had found an association between the chemicals and ovary function disruption, irregular menstrual cycles, earlier age of menopause, and reduced levels of the hormone types estrogens and androgens.⁴

Other studies on animals have linked PFAS chemicals to cancer, fetal development issues, and toxicity to the liver, kidneys, and immune system. Some research has shown that the chemicals can accumulate in the brains of both humans and wildlife.⁵

What Exactly Does the New Rule Require?

The new regulation limits the presence in public drinking water of two PFAS chemicals, PFOA and PFOS, to a maximum of 4 parts per trillion—the lowest amount feasible. It also puts the maximum amount of other chemicals—PFNA, PFHxS, and HFPO-DA (also called GenX chemicals)—at ten parts per trillion. The EPA also set a limit of ten parts per trillion for any mixture that includes two or more of the chemicals mentioned as well as another type called PFBS.²

“There are certainly thousands of PFAS on which there is not enough data to determine if they are dangerous,” Orlando Coronell, PhD, a professor in the Department of Environmental Sciences and Engineering at the University of North Carolina at Chapel Hill Gillings School of Global Public Health, told Health. “These new regulations limit those commonly found in water and for which the evidence is clear that they are health hazards.”

The EPA’s new standards are much more stringent than the non-legally binding guidelines it released in 2016, which set PFAS and PFOS limits at 70 parts per billion.⁶ Last March, the EPA announced it was considering limiting certain PFAS in U.S. drinking water. 

Eleven states have also placed limits on certain PFAS in drinking water, but the new federal rule will take precedence if it is stricter than a state’s regulation. Twelve additional states have health advisories or non-binding guidance on PFAS levels in drinking water.⁷

Moving Forward

The rule applies to 66,000 public water systems and gives them time to comply before it goes into effect.

Systems will have to complete initial monitoring of the PFAS by 2027, per the regulation, at which point they’ll have to make the information public. If monitoring shows that PFAS levels exceed standards, they will have by 2029 to implement solutions to reduce the amount of PFAS in their drinking water.

The EPA said it set aside an initial $1 billion to upgrade drinking water systems that cannot filter enough PFAS to meet the federal standards. The agency expects that about 10% of public drinking water systems will have to make updates.

Beginning in 2029, public water systems that violate the new standards must attempt to reduce levels and notify the public of the violation.

Given that the federal rule will take several years to go into effect, Rumpler recommends that people concerned about PFAS in their drinking water buy a filter designed to catch the chemicals.

People who drink water from non-public systems, such as private wells, may also want to use a filter, he said.

Though the EPA noted that part of the $1 billion will address PFAS contamination in private wells, particularly common in rural areas, it’s unclear how people will access this money or whether it would be used for testing.

“Installing home water treatment solutions or even testing the water may be cost-prohibitive for lower-income households,” Coronell noted.

Rumpler said, however, that the new rule is a significant step in reducing PFAS exposure overall. Still, he doesn’t think it goes far enough.

“Just saying we’re putting a limit on how much can be in our drinking water doesn’t solve the problem. It just means there is a responsibility that utilities will have to remove them,” Rumpler said. “We need to get them out of our products because every time you manufacture carpet or clothing with PFAS, those PFAS get into the environment.”