For years, the evidence linking PFAS contamination in drinking water to human health harm has accumulated primarily from laboratory studies, animal models, and epidemiological analyses of occupational exposure. The missing piece has been large-scale, clinical, community-based research directly documenting health outcomes in everyday Americans living with PFAS in their tap water. That piece has now arrived.
The Agency for Toxic Substances and Disease Registry (ATSDR) published results from its landmark Multi-Site PFAS Health Study in June 2026 — the largest clinical investigation ever conducted in United States communities with PFAS-contaminated drinking water. The study enrolled adults aged 18 and older and children aged 4 to 17 from eight sites across California, Colorado, Massachusetts, Michigan, New Hampshire, New York, New Jersey, and Pennsylvania — communities with documented past or ongoing PFAS contamination of their drinking water. Participants underwent extensive clinical testing assessing cardiometabolic health, liver function, thyroid function, kidney function, blood sugar regulation, and immune system parameters. Children also received neurobehavioral assessments.
