Non-toxicity becomes federal law: EPA's first enforceable PFAS drinking-water limits
On 26 April 2024 the US EPA issued the first legally enforceable national drinking-water limits for PFAS — 4.0 parts per trillion each for PFOA and PFOS (health goal: zero), plus limits for PFHxS, PFNA and GenX (89 FR 32532). As of June 2026 EPA proposes keeping the PFOA/PFOS limits while extending compliance to 2031 and rescinding the four co-contaminant limits. "Non-toxic" shifted from a voluntary virtue to a federal mandate with a number attached.
The 2024 PFAS National Primary Drinking Water Regulation set Maximum Contaminant Levels of 4.0 ng/L (ppt) for PFOA and PFOS, with maximum contaminant level goals of zero, and limits for PFHxS, PFNA and HFPO-DA (GenX) plus a Hazard Index for mixtures (Federal Register, 89 FR 32532; effective 25 June 2024). It was the first time the US set enforceable federal drinking-water limits for any PFAS.
Why it matters (spine): this is the regulatory engine behind the non-toxic spine — it converts toxicology into mandatory demand for clean water and PFAS-free materials, and it makes verified contaminant data a procurement input, not a talking point.
Live status (checked 2026-06-27): EPA's May 2026 proposals (Fed. Reg. 2026-05-20) would keep the PFOA/PFOS limits but extend compliance to 2031 and rescind the four co-contaminant limits — a proposal, not a final rule. The 2024 MCLs remain operative.
Falsifier: a final rule repealing the PFOA/PFOS MCLs. · Confidence: 0.95 (the 2024 rule is primary and in force; future policy is the uncertainty).
Provenance: US EPA, Federal Register, Document Citation 89 FR 32532 (filing). Verified text: "enforceable MCLs for PFOA and PFOS at 4.0 ng/L."
So we should treat PFAS removal capacity and PFAS-free substitution as durable bets for BKG/NMK, and track the rescission docket as priced-in risk.
Treat PFAS removal (GAC / ion-exchange / RO) and PFAS-free material substitution as durable procurement criteria; price the 2026 proposed rescission as regulatory risk, not a settled reversal.
domains: pfas · toxicology · water · non-toxic-materials · regulation