WATER FILTRATION

Author

PERLA BORTEL

0.1 💧 PFAS in Drinking Water: Summary of Science, Regulation, and Treatment (EPA 2024–2025)

What Are PFAS?

Per- and polyfluoroalkyl substances (PFAS) are synthetic chemicals used since the 1940s in non-stick cookware, waterproof textiles, and firefighting foams. Their strong carbon-fluorine bonds make them extremely stable, earning the name “forever chemicals.” PFAS accumulate in soil, water, and human bodies, leading to health risks including cancer, immune suppression, hormonal disruption, and developmental effects.

EPA’s 2024–2025 Regulations

The U.S. Environmental Protection Agency (EPA) set the first national drinking-water standards for PFAS in April 2024.

  • Maximum Contaminant Levels (MCLs): 4 ppt for PFOA & PFOS (the most toxic PFAS).

  • Additional Compounds Regulated: PFHxS, PFNA, and GenX at 10 ppt each.

  • Hazard Index: Measures combined risk for PFAS mixtures.

  • Timeline: Utilities must test within 3 years and comply within 5.

These are the strictest limits ever set for any drinking-water contaminant and aim to protect about 100 million Americans.

Sources and Risks

PFAS enter groundwater from industrial runoff, landfills, and firefighting foams. They persist for decades, spreading through soil and aquifers. Even at trace levels (parts per trillion), PFAS exposure is harmful over time, particularly for pregnant women and children.

1 Treatment Technologies

Traditional filters or water softeners do not remove PFAS. Effective solutions include:

  • Granular Activated Carbon (GAC): Adsorbs long-chain PFAS; cost-effective but less efficient for short-chain variants.

  • Ion Exchange (IX): Uses charged resins to capture PFAS ions; effective for most types but more expensive.

  • Reverse Osmosis (RO): Physically filters both long- and short-chain PFAS through membranes; highly effective but slower and produces wastewater.

Funding and Implementation

The Infrastructure Investment and Jobs Act provides $9 billion for PFAS cleanup, $12 billion for general water infrastructure, and $1 billion in grants for small or disadvantaged communities.

Your Role as a Consumer

  • Test your water through a certified lab.

  • Use certified filters (NSF/ANSI 53 or 58).

  • Maintain filters per manufacturer guidance.

  • Stay informed via local and EPA updates.

  • Reduce PFAS use at home (avoid stain-resistant and non-stick products).

2 PFAS Contamination & Water Filtration Guide (EPA, 2024)

WHAT ARE PFAS?

  • Synthetic chemicals (used in non-stick, stain-resistant, and firefighting materials).

  • - Persist in water, soil, and human bodies - cause long-term exposure risks.

  • Linked to liver damage, immune suppression, and some cancers (EPA, 2024).

HOW DO THEY ENTER WATER?

  • Industrial discharge, landfill leachate, and firefighting foam runoff.

  • Detected in drinking water in several U.S. states, including California & Arizona.

EFFECTIVE FILTRATION METHODS (EPA, 2024):

  • Granular Activated Carbon (GAC)

  • lon Exchange Resins (IX)

  • Reverse Osmosis (RO)

  • Basic carbon or sediment filters # PFAS removal

WHAT TO DO

  • Test your water for PFAS levels.

  • Use NSF/ANSI 53 or 58 certified filters.

  • Replace cartridges/membranes on schedule.

3 REFERENCES

U.S. Environmental Protection Agency. (2025). PFAS National Primary Drinking Water Regulation.

U.S. Environmental Protection Agency. (2024). Identifying Drinking Water Filters Certified to Reduce PFAS.

U.S. Environmental Protection Agency. (2025). Reducing PFAS in Drinking Water with Treatment Technologies.

Kel Tren WaterCare. (2025, Aug 25). The Science Behind PFAS Removal: Activated Carbon vs. Reverse Osmosis.