EWG TAP WATER DATABASE

What's Really in
Your Tap Water

The Environmental Working Group's Tap Water Database has analyzed water quality data from more than 48,000 utilities serving 280 million Americans. Their findings reveal that hundreds of contaminants are present in U.S. drinking water — many at levels that exceed health guidelines, even when they meet legal standards.

Contaminant Exposure Health Risk EWG Finding
PFAS (Forever Chemicals) 2,858 systems Cancer, immune disruption, developmental harm No safe level established
Lead 186M Americans Brain damage, developmental harm in children No safe level — causes harm at any dose
Chromium-6 250M Americans Carcinogen linked to stomach cancer Legal limit 500× higher than safe level
Nitrates Widespread Infant illness, thyroid disruption, colorectal cancer Legal limit may be too high
Arsenic 77M Americans Bladder, lung, and skin cancers Legal limit 50× higher than cancer risk level
Chloroform (THMs) Most U.S. systems Cancer, reproductive harm Byproduct of chlorine disinfection
Atrazine (Herbicide) 30M Americans Endocrine disruption, reproductive harm Detected in 90% of U.S. water samples
Source: Environmental Working Group Tap Water Database — ewg.org/tapwater