The Filthy Truth About Your Tap Water

Following years of concern, the US Environmental Protection Agency moved this week to clean up drinking water, announcing the nation’s first standards for six “forever chemicals” found in tap water. It’s a foreboding and informal name for human-made chemicals that coat nonstick pans, food packaging, and waterproof clothes before ending up in the water you drink. These chemicals, known as PFAS, or per- and polyfluoroalkyl substances, are pervasive and found in pretty much everyone—even newborn babies.

If the EPA rule is finalized, public water companies will need to monitor for the chemicals and keep two widely studied ones, PFOA and PFOS, below levels of 4 parts per trillion—around the lowest threshold measurable. The rule will also regulate combined amounts of four other types of PFAS chemicals. 

Experts say the proposal is monumental. It marks not just the first US national standard for regulating levels of these chemicals, but would also allow for widespread data collection to see which communities are most affected by contamination. Implementing these much needed fixes could take years and will be costly. Still, experts see this as a significant first step in pushing back against the PFAS problem, and one that could vastly improve water quality across the nation. 

“These are very strong, health protective, and a historic move to really limit exposure to contamination from these chemicals,” says David Andrews, a senior scientist at the Environmental Working Group, a nonprofit focused on health and environmental advocacy. “There are lots of opportunities to build off of this.” 

The PFAS regulation is not yet a reality; it’s a proposed measure that could be finalized this year after a public comment period. If it is formally adopted, it will result in new expenses for many public water systems, requiring not only testing but filtering water when contaminants are detected. The utilities would have three years to comply with the rule, so some communities might not see results until 2026. 

The dangers of PFAS chemicals have become increasingly clear. High levels of exposure can cause fertility issues, developmental delays in children, and reduced immune responses, according to the EPA. They can also elevate the risk of several cancers, including prostate, kidney, and testicular cancer. 

The US National Academies of Sciences, Engineering, and Medicine released a report in 2022 saying health care providers should counsel and test patients who are more likely to have elevated PFAS exposure based on where they live or work. And EPA officials estimate that cleaning up the water will prevent thousands of deaths—and tens of thousands of cases of serious illness—in the US. 

Regulating the two commonly studied chemicals, as well as four additional ones, is “a really important first step,” says Katie Pelch, a scientist with the Natural Resources Defense Council (NRDC), a nonprofit environmental advocacy group. But there is more to learn about this vast group of chemicals and their prevalence. “This is still just a proposal to regulate six PFAS out of a class of thousands of chemicals,” she continues. The processes to remove PFAS could also tackle other chemicals found in drinking water, such as those from pharmaceuticals, flame retardants, and consumer products.