As PFAS drinking water regulation has proliferated globally, manufacturers, water utilities, and technology suppliers face a complex mosaic of standards that vary significantly in the compounds covered, the concentration limits set, the approach taken (individual compound vs. sum-of-PFAS), and the enforcement mechanisms deployed. This comparison provides a current snapshot of the major regulatory frameworks as of mid-2026—an essential reference for any OEM filter manufacturer or water treatment supplier operating across international markets.
United States (Federal): EPA MCLs
Standard type: Maximum Contaminant Levels (MCLs) — legally enforceable federal requirements for public water systems. PFOA: 4 ng/L (individual). PFOS: 4 ng/L (individual). PFHxS, PFNA, HFPO-DA (GenX): Originally 10 ng/L each; EPA proposed rescission in fall 2025, final rule expected spring 2026. Compliance deadline: PFOA/PFOS — originally 2029, extended to 2031 (May 2025 announcement). Scope: All public water systems serving 25+ people. Status: PFOA/PFOS MCLs retained; four other compound MCLs under proposed rescission. Individual state standards may be stricter and remain in force regardless of federal changes.
European Union: Drinking Water Directive
Standard type: Parametric values — legally binding requirements under EU Drinking Water Directive 2020/2184, transposed into national law by January 12, 2023. Sum of 20 PFAS: 100 ng/L (total concentration of 20 named PFAS including PFOA, PFOS, PFNA, PFHxS, and 16 others). Individual PFAS not on list of 20: 0.5 ng/L per compound. Scope: All water intended for human consumption in EU member states. Status: In force. Transposition complete in most member states; infringement proceedings against late transposers.
Japan: Waterworks Act Standard
Standard type: Water quality standard — legally binding under the Waterworks Act, effective April 1, 2026. PFOS + PFOA (combined): 50 ng/L. Testing frequency: Quarterly for all public water supply systems. Scope: All municipal water supply systems, small water supplies, and regulated private wells. Mineral water: Same 50 ng/L combined limit, effective from Consumer Affairs Agency ordinance. Status: Fully in force from April 1, 2026. Previously a management target value; now an enforceable standard.
Canada: Health Canada Drinking Water Objective
Standard type: Drinking water objective — advisory, not federally binding; adopted as binding standard by most provinces. Sum of 25 PFAS: 30 ng/L. Scope: All drinking water supplies; federal objective guides provincial enforceable standards. Status: Interim guidance while comprehensive health-based guidelines are developed (expected to take several years). Non-polymeric PFAS listed on CEPA Schedule 1 as toxic substances as of March 2025.
Australia: NHMRC Drinking Water Guidelines
Standard type: Health-based guideline values — advisory at national level; adopted as binding standards by states and territories. PFOS: 8 ng/L (revised downward, June 2025). PFOA: 200 ng/L. PFHxS: 30 ng/L. PFBS: 1,000 ng/L. Status: Updated June 2025; adoption into state/territory standards ongoing. Separate prohibition on PFOS, PFOA, and PFHxS import and use from July 1, 2025.
United Kingdom
Scotland: Statutory standard of 0.1 µg/L (100 ng/L) for sum of 20 named PFAS — in force since January 1, 2023. England and Wales: DWI quality event trigger at 0.1 µg/L for sum of 48 named PFAS; statutory limit consultation announced for 2026. Status: UK PFAS Plan published February 2026; statutory England limit expected to be consulted in 2026.
South Korea
PFOS + PFOA (combined): 70 ng/L. PFHxS: 480 ng/L (provisional target). Status: Among the least stringent in developed Asia; 2025 academic policy paper calls for revision to align with US/EU standards. No soil or groundwater PFAS standards established.
New Zealand
PFHxS + PFOS (combined): 70 ng/L. PFOA: 560 ng/L. Status: Last updated November 2022; regulator Taumata Arowai has stated no plans to revise. Substantially higher than Australian, U.S., and EU standards.
WHO Global Guidelines (2022)
PFOS: 100 ng/L. PFOA: 100 ng/L. PFHxS: 600 ng/L. PFNA: 90 ng/L. Status: Reference standard for countries without domestic regulatory frameworks. Already less stringent than U.S., EU, Canadian, and Australian standards. Update expected within 3–5 years.
Key Takeaway for OEM Filter Manufacturers
The global PFAS standard landscape is moving in one clear direction: toward stricter limits, broader compound coverage, and enforceable requirements that create real compliance consequences for water utilities. The U.S. 4 ng/L MCL for PFOA and PFOS represents the current global floor for advanced economies, and it is the most commercially relevant target for OEM manufacturers seeking to develop products with a defensible multi-market performance claim. Filter systems certified to 4 ppt PFOA/PFOS removal performance under NSF/ANSI 53 will meet or exceed the current enforceable standards of the U.S., EU, Japan, Canada, and Australia simultaneously—making this the most strategically valuable certification target for manufacturers operating across international markets.