Department of Health
331-673 • Revised November 1, 2021
Summary
In October 2017, the State Board of Health (board) accepted a petition from ten organizations to establish drinking water standards for per- and polyfluoroalkyl substances (PFAS). Board authority to adopt such standards comes under RCW 43.20.050(2), RCW 70.119.080(1), and RCW 70.142.010.
To support the board, the Washington Department of Health (department) released draft state action levels (SALs) for five PFAS in November 2019. These PFAS occur in Washington drinking water and had sufficient scientific information to recommend a value. We presented the draft rule language at stakeholder workshops and at numerous meetings with stakeholders. After evaluating the feedback from these events and from two public comment periods, we updated our technical document and lowered our recommendation for the PFBS SAL from 1,300 to 345 ng/L to better protect infants. We also revised the PFNA SAL from 14 to 9 ng/L based on new evidence of serum half-life in humans. The PFHxS SAL was revised slightly to correct our calculation of average maternal body weight used in the infant exposure model. The revised SAL values are part of the proposed rule being considered for adoption by the State Board of Health in 2021.
Continue reading “Recommended State Action Levels for Per- and Polyfluoroalkyl Substances (PFAS) in Drinking Water: Approach, Methods, and Supporting Information”