First National Limits for PFAS in Drinking Water Proposed
US EPA is proposing drinking water limits for six per- and polyfluoroalkyl substances (PFAS). The regulation would create the nation’s first-ever national limits for a widely used class of substances nicknamed “forever chemicals” because they do not break down over time.
The proposed rule would establish Maximum Contaminant Levels (MCLs) for these PFAS:
- PFOA (perfluorooctanoic acid),
- PFOS (perfluorooctane sulfonic acid),
- PFNA (perflouorononanoic acid),
- HFPO-DA or “GenX” (hexafluoroproplyene oxide dimer acid),
- PFHxS (perfluorohexane sulfonic acid), and
- PFBS (perfluorobutane sulfonic acid).
The proposed MCLs for these six PFAS as follows:
- For PFOA, 4.0 parts-per-trillion
- For PFOS, 4.0 parts-per-trillion
- For the other four PFAS, an MCL of 1.0*
*The MCL of 1.0 is cumulative, based on a Hazard Index (HI) combining various risk factors.
The proposed rule also creates unenforceable health-based level of zero for PFOA and PFOS.
A pre-publication version of the proposed rule is available now.
The official proposed rule should be published to the Federal Register in short order. Lion will update this post on the same day it's published.
About National Primary Drinking Water Regulation (NPDWR)
The Safe Drinking Water Act authorizes US EPA to create National Primary Drinking Water Regulations (NPDWR). These regulations generally include limits on the concentration in drinking water of certain kinds of substances—microorganisms, organic and inorganic chemicals, disinfectants, and radionuclides.
Public water systems or PWS (defined in 40 CFR 141.3) must notify customers via specified means whenever they detect a violation of a NPDWR.
Webinar: Complete Environmental Regulations Training
Join a Lion instructor for the next Complete Environmental Regulations Webinar on May 18–19. Get an overview of US EPA’s major air, water, and chemical programs—from the Clean Air and Clean Water Acts to EPCRA, TSCA, Superfund, and more.
Prefer to train right now, at your own pace? Try the interactive online course.
Tags: drinking water, PFAS
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