About
The forever chemicals, explained.
PFAS — per- and polyfluoroalkyl substances — are a family of thousands of synthetic chemicals used since the 1940s for their water, grease, and heat resistance. Their carbon–fluorine bonds barely break down in the environment or in our bodies. That's why scientists call them forever chemicals.
Where they end up
Drinking water, soil, livestock, fish, breast milk, and the blood of nearly every person tested in the U.S.
How they get there
Industrial discharge, AFFF firefighting foam, biosolids spread on farmland, landfill leachate, and consumer products.
Linked health effects
Kidney and testicular cancer, thyroid disease, immune suppression, high cholesterol, low birth weight, and reduced vaccine response.
What helps
Granular activated carbon and reverse-osmosis filters, switching cookware, avoiding stain-resistant treatments, and supporting source-reduction policy.
How we rate risk
For drinking-water sites, we anchor to the EPA's 2024 enforceable limits (4 ppt for PFOA and PFOS). For products, we score based on documented PFAS presence, exposure pathway, and the availability of PFAS-free alternatives.
Low
Below EPA enforceable limit (4 ppt).
Elevated
Above EPA limit; ongoing exposure may pose risk.
High
Significantly elevated; filtration or alternatives recommended.
Severe
Well above health advisories. Avoid use; seek professional guidance.
Maine-specific resources
- Maine DEP — PFAS investigation
- Maine CDC — PFAS health information
- LD 1503 — products containing PFAS
- EPA — PFAS in drinking water
Clearwater is an educational tool. It is not medical, legal, or regulatory advice. For testing or health concerns, contact your state environmental agency or healthcare provider.