Water

OEHHA performs major risk assessment and hazard evaluation activities relating to chemical contaminants in drinking water. These activities include developing health advisories, Public Health Goals for chemical substances in drinking water, Notification Levels, and providing toxicological assistance for chemical monitoring activities for the drinking water supply. The program also provides education to the public and other governmental agencies on drinking water contamination and drinking water regulatory standards development.

Public Health Goals

Level of a chemical contaminant in drinking water that does not pose a significant risk to health

Notices

Legal notices for Public Health Goals and Notification Levels

Notification Levels

Health-based advisory levels for chemicals in drinking water

Reports

Reports focusing on water

Human Right to Water

OEHHA’s assessment framework and data tool related to drinking water quality, accessibility, and affordability

Reports, Notices, Documents

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 development of a public health goals (PHG) for Perfluorohexane Sulfonic Acid and update of the PHG for arsenic are both being initiated at the request of State Water Resources Control Board. The PHG development/update will incorporate relevant new data. Office of Environmental Health Hazard Assessment is requesting information on these contaminants that could assist in conducting the risk assessments and in calculating the PHGs.
The Office of Environmental Health Hazard Assessment (OEHHA) is announcing the availability of a second draft document describing a proposed health-protective concentration (HPC) for noncancer effects of hexavalent chromium (Cr(VI)) in drinking water, as part of the update to the Cr(VI) Public Health Goal (PHG).

This document contains health risk information on regulated drinking water contaminants to assist public water systems in preparing these reports. NEW for the 2022 Report: New in this document are an updated Public Health Goal (PHG) for 1,2-dibromo-3-chloropropane (DBCP) and newly established PHGs for the trihalomethanes bromodichloromethane, bromoform, chloroform, and dibromochloromethane.

The Office of Environmental Health Hazard Assessment (OEHHA) is announcing a proposed updated Public Health Goal (PHG) for N-nitrosodimethylamine (NDMA) in drinking water, the availability of a draft technical support document, a 45-day public comment period, and a hybrid public workshop on January 24, 2025.