By the Numbers
12,000+
Known PFAS compounds
200M+
Americans with PFAS in Tap Water
700+
Military Bases Contaminated
4 ppt
EPA Limit for PFOA & PFOS
$13B+
Manufacturer Settlements
2031
Utility Compliance Deadline
The Basics
What Are PFAS?
PFAS — per- and polyfluoroalkyl substances — are a family of more than 12,000 synthetic chemicals sharing one characteristic: a carbon-fluorine bond so strong that no natural process breaks it down. Not sunlight. Not soil bacteria. Not your body’s metabolism. That is why they are called forever chemicals.
They went into non-stick cookware, firefighting foam, food packaging, and stain-resistant fabrics starting in the 1940s. For decades, manufacturers knew about accumulation in human blood and kept it from regulators and the public. Today, PFAS are in the blood of virtually every American tested.
New Here?
Start With These Four Steps
01
Check your water
Search ewg.org/tapwater with your zip code to see what forever chemicals have been detected in your water system.
02
Understand the Risk
Read PFAS 101 for the science and Health Effects for what the evidence says about your health.
03
Reduce Your Exposure
See Action Steps for a prioritized checklist — from filtering your water to safer products in your home.
04
Know Your Rights
Read Your Rights to understand what your water utility is required to tell you and how to demand action.
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Regulation of Forever Chemicals
Recent Regulatory Updates
Jan 2026
D.C. Circuit Court denies EPA’s request to pause enforcement of PFAS MCLs for PFNA, PFHxS, and GenX. Standards remain in effect. Current status →
May 2025
Trump administration EPA extends PFOA and PFOS compliance deadline from 2029 to 2031. The 4 ppt MCLs remain in effect; utilities have additional time to install treatment systems.
Apr 2024
EPA finalizes first national drinking water standards for six PFAS. PFOA and PFOS MCLs set at 4 ppt. PFOA classified as a human carcinogen under CERCLA.
Jun 2023
3M agrees to pay up to $12.5 billion to settle claims from public water utilities contaminated by PFAS from AFFF foam. DuPont entities settle separately for $1.185 billion.



