This year’s update to the Environmental Working Group’s Tap Water Database shows millions of Americans are drinking water tainted with harmful chemicals, heavy metals and radioactive substances. Many of these contaminants are at levels far above what scientists consider safe.
EWG’s latest analysis includes water quality data collected between 2021 and 2023 from nearly 50,000 water systems. It identified 324 contaminants in drinking water across the country, with detectable levels in almost all community water systems.
“This is a wake-up call,” said Tasha Stoiber, Ph.D., a senior scientist at EWG. “For over 30 years, EWG has been at the forefront of advocating for stronger drinking water protections. Outdated federal regulations continue to leave millions of people at risk of exposure to harmful substances.
“Our Tap Water Database is the only resource providing consumers in every state access to accurate information about water contaminants, health risks and steps to reduce exposure through filtration – information they need so they can take action,” she said.
The levels of contamination in many locations fall largely below the Environmental Protection Agency’s outdated legal limits. But they often far exceed EWG’s health-based standards, the sweeping analysis of nationwide water utility tests found.
The Tap Water Database empowers virtually everyone in all 50 states and the District of Columbia to check local water quality and take action to improve it, if necessary. By entering their ZIP code, users can easily find detailed information about the contaminants in their local water supply, including tips on choosing the right water filter to reduce exposure.
“Consumers shouldn’t need to worry if their water is safe to drink,” said Sydney Evans, a senior science analyst at EWG. “The burden also shouldn’t fall to individuals to filter out hazardous substances that shouldn’t be in water taps to begin with.”
The update highlights contaminants in U.S. drinking water, including the toxic “forever chemicals” known as PFAS, that are in the drinking water of over 143 million people. Tap water throughout the U.S. can also contain volatile organic compounds, nitrate and arsenic, among many other contaminants. These pollutants, often linked to cancer, developmental issues and other health risks, are found in nearly all community water systems.
Harmful disinfection byproducts and radiological contaminants also persist in water supplies in many communities.
Hexavalent chromium, or chromium-6, is a carcinogen made infamous by the Erin Brockovich case in Hinkley, Calif., and it’s in the drinking water of over 250 million Americans. There is no federal limit for chromium-6, despite its widespread presence and link to cancer and organ damage.
EPA efforts to safeguard drinking water continue to lag
Despite mounting scientific evidence and public concern about U.S. drinking water quality, federal action remains slow. In 2024, the Biden EPA introduced its first drinking water standards in more than 20 years, setting health-protective maximum contaminant limits for six PFAS.
“For too long, outdated federal standards have failed to reflect the latest science on drinking water, leaving millions exposed to harmful chemicals,” said Melanie Benesh, vice president of government affairs at EWG. “While the new PFAS standards represent a historic step forward, they are only a fraction of what is needed to protect public health.”
The EPA standards are critical in reducing PFAS contamination in the nation’s water supply. But these vital new protections could be at risk if the Trump administration tries to roll them back, along with weakening other steps the Biden EPA took to tackle PFAS pollution.
“Safe drinking water shouldn’t be a political debate – it’s a fundamental right. A rollback of these hard-won protections would be a devastating setback. We must push for stronger, science-based regulations to ensure safe water for every American,” said Benesh.
