Clean Water, Unequal Reality in the PFAS Era

A new EWG study reveals only 8% of US water systems have PFAS filters, exposing market inequities and reshaping treatment demand

9 Sep 2025

A widening gap in access to advanced water treatment is emerging across the US, as new research highlights limited adoption of filtration capable of removing per- and polyfluoroalkyl substances (PFAS).

A peer-reviewed study published in September 2025 in ACS ES&T Water by the Environmental Working Group (EWG) found that only 8 per cent of US water systems have installed such filtration, despite PFAS being detected in drinking water serving more than 172m Americans. The disparity is increasingly shaping expectations among utilities, suppliers and investors.

The study points to uneven adoption across system sizes. Just 7 per cent of very small systems serving fewer than 500 people use advanced filtration, compared with 28 per cent of the largest utilities. EWG science analyst Varun Subramaniam described the pattern as “a textbook case of environmental injustice” and warned that without targeted investment, the divide could deepen.
The findings have prompted a shift in how demand is assessed, with greater focus on structural barriers, including funding and technical capacity, that limit uptake among smaller providers.

The research also identified secondary benefits from PFAS treatment. Across 19 utilities with advanced filtration, trihalomethane levels fell by an average of 42 per cent, while haloacetic acids declined by 50 per cent. Both are regulated disinfection byproducts linked to cancer risk. EWG senior science analyst Sydney Evans said PFAS treatment “is opening the door to broader water quality improvements,” strengthening the case for investment beyond regulatory compliance.

At the federal level, policy signals remain mixed. In May 2025, the Environmental Protection Agency confirmed it would retain limits for PFOA and PFOS, while proposing to rescind standards for four other PFAS compounds and extend compliance deadlines from 2029 to 2031. The extension has tempered near-term procurement expectations.

Reflecting this, the Environmental Business Journal revised its long-term market estimate to about $132m in late 2025, down from $230m projected after the EPA’s 2024 rulemaking.

State-level activity, however, continues to expand. More than 200 PFAS-related bills were introduced across over 30 states in 2025, with several jurisdictions moving to match or exceed federal standards. At the same time, household demand for point-of-use systems such as reverse osmosis and activated carbon is rising, particularly in areas underserved by utility upgrades.

For suppliers and investors, the main opportunity lies in extending treatment to smaller systems, where public funding remains available but underutilised.