A survey of nearly 50,000 water networks nationwide revealed a staggering 324 different contaminants flowing out of American taps — with detectable levels of various pollutants showing up in nearly all water systems.
The findings, from this year’s update to the Environmental Working Group’s (EWG) Tap Water Database, reveal that millions of people could be consuming water tainted with toxic chemicals, heavy metals and radioactive compounds, often at levels much higher than what scientists consider safe.
“This is a wake-up call,” Tasha Stoiber, a senior scientist at EWG, said in a statement. “Outdated federal regulations continue to leave millions of people at risk of exposure to harmful substances.”
The massive database provides a ZIP code-level window into the specific contaminants affecting community drinking water supplies, compiled from water quality data collected between 2021 and 2023.
Upon entering a specific ZIP code into the search bar, users can scroll down to select the utility that serves their community. The database then specifies the concentrations of “contaminants detected” alongside a comparison of EWG’s health guidelines.
Alongside the results is a caveat that “legal does not necessarily equal safe,” with a warning that in many cases, the “legal limits for contaminants in tap water have not been updated in almost 20 years.”
Of particular concern to the researchers was the nationwide prevalence of cancer-causing “forever chemicals,” which appeared in the drinking water of more than 143 million people.
There are thousands of types of these synthetic compounds, also known as per- and polyfluoroalkyl substances (PFAS), which are common ingredients in household items like waterproof apparel, nonstick pans and certain kinds of cosmetics.
While the Biden administration in 2024 set drinking water standards for six types of PFAS, scientists have shown that for the most notorious of these chemicals, there is no safe consumption level.
Another compound of concern was hexavalent chromium, or chromium-6, which came into the public eye through the work of environmental activist Erin Brockovich, in Hinkley, Calif. This carcinogenic form of chromium is present in the drinking water of more than 250 million Americans, and there is no federal limit on the substance.
Other pollutants that alarmed the EWG researchers were volatile organic compounds, like trichloroethylene (TCE), nitrates, heavy metals like arsenic and disinfection byproducts.
In Washington, D.C., some of the biggest offenders were nitrates, hexavalent chromium, radium and lead.
Los Angeles’s drinking water contained the radioactive contaminant uranium, hexavalent chromium, lead and disinfection byproducts.
As for New York City, pollutants in the drinking water system included hexavalent chromium, chloroform and various disinfection byproducts.
“For too long, outdated federal standards have failed to reflect the latest science on drinking water, leaving millions exposed to harmful chemicals,” Melanie Benesh, vice president of government affairs at EWG, said in a statement.
Since the Trump administration took office, environmental activists have feared that certain existing standards could be rolled back and further complicate efforts to clean up American water supplies. It remains to be seen, however, what — if any — such action will be taken.
“Safe drinking water shouldn’t be a political debate — it’s a fundamental right,” Benesh said. “A rollback of these hard-won protections would be a devastating setback.”
