Given the widespread use of PFAS chemicals, experts have said the chemicals’ presence in drinking water is not all that surprising.
The Environmental Protection Agency (EPA) has been rolling out waves of data showing which locations across the country have the highest levels of PFAS contamination in drinking water systems.
The findings, collected and put on a map by the Environmental Working Group (EWG), show that the Eastern side of the country has a significantly higher number of locations with levels of PFAS chemicals above accepted limits than the West.
The data is from the EPA’s Fifth Unregulated Contaminant Monitoring Rule, known as UCMR 5, requiring U.S. water utilities to test drinking water for 29 individual PFAS compounds.
Earlier this month, the EPA released the ninth wave of data, which showed that 7 million more Americans were drinking water contaminated with PFAS chemicals than what was found in the previous release—bringing the total to 172 million, according to EWG.
The EPA previously told Newsweek: « On April 28, 2025, the agency announced a suite of actions to address PFAS, including in water. »
The agency added: « This list is the first, not the last, of all decisions and actions EPA will be taking to address PFAS over the course of the Trump Administration. »Why It Matters
PFAS chemicals are a group of thousands of different substances, which are classified as a Group 1 carcinogen by the International Agency for Research on Cancer.
Since the classification, research has continued to unravel their potential health risks – such as thyroid disease, liver disease, weakened immunity and many other health problems.
Despite their health risks, PFAS chemicals are highly favored in many industries for their long-lasting nature, featuring in many consumer products and even smartwatch wristbands.
Given their widespread use, experts have said that data continuing to reveal the chemicals’ presence in drinking water is not all that surprising.
