Proposed Public Health Goal (PHG) for 1,4-Dioxane in Drinking Water
OEHHA is extending the public comment period by 15 days on the draft technical support document for the proposed Public Health Goal (PHG) for 1,4-dioxane in drinking water. The comment period will now close on November 25, 2025. The extension is in response to a request from the American Chemistry Council.
The 45-day comment period begins on September 26, 2025, and is scheduled to end on November 10, 2025.
On November 13, 2025, OEHHA will host a hybrid public workshop on the draft technical document.
Workshop location:
CalEPA Building
Training Room 2 East and West
1001 I St.
Sacramento, CA 95814
Time:
9:00 a.m. to 12:00 p.m. Pacific Time
Public Health Goal Initiation Notice
In March 2020, OEHHA initiated the development of a PHG for 1,4-dioxane, in response to a request from the SWRCB. OEHHA also had a data call-in for any information relevant to the establishment of the PHG.
Background on the PHG Program
The Calderon-Sher California Safe Drinking Water Act of 1996 (Health and Safety Code section 116365), hereafter referred to as the Act, requires OEHHA to post a notice on its website when it initiates work to develop or update PHGs. PHGs are concentrations of chemicals in drinking water that are not anticipated to produce adverse health effects. OEHHA is required to consider potential adverse effects on members of sensitive subgroups of the population, including infants, children, pregnant women, the elderly, and individuals with a history of serious illness.
PHGs are nonregulatory in nature but are used as the health basis for SWRCB to establish the state's primary drinking water standards or MCLs. At the initial posting of a draft document, OEHHA provides a 45-day public comment period. OEHHA also conducts a public workshop to receive public comments and engage in dialogue with interested parties on the draft document. An external scientific peer review is then conducted as required by Health and Safety Code section 116365(c)(3)(D). OEHHA considers all relevant comments in the preparation of a revised draft, which is posted for a 30-day public comment period. After consideration of any additional comments, the PHG is finalized and posted on the OEHHA website for public reference and for use by SWRCB in developing California MCLs.
All PHGs and their supporting documents are available on OEHHA's website.