The Office of Environmental Health Hazard Assessment (OEHHA)

Our mission is to protect and enhance the health of Californians and our state’s environment through scientific evaluations that inform, support and guide regulatory and other actions.

To learn more about OEHHA click here.

Wild Fire Smoke - A Guide for Public Health Officials is designed to help local public health officials prepare for smoke events, take measures to protect the public when smoke is present, and communicate with the public about wildfire smoke and health.

Protecting Public Health from Home and Building Fire Ash This report summarizes safe methods of ash cleanup. Protección de la Salud Pública contra las Cenizas de Incendios en Casas y Edificios (Spanish)


For more information on: How Smoke from Fires Can Affect Your Health


Feb 11, 2019: 2018 Indicators of Climate Change in California
Explore the indicators that show how climate change is affecting California. These scientifically-based measurements track trends in various aspects of climate change and are useful for communicating information about the climate change issues confronting the state.
Feb 7, 2019: Health Risk Information for Public Health Goal Exceedance Reports
This document contains health risk information on regulated drinking water contaminants to assist public water systems in preparing these reports. A PHG is the concentration of a contaminant in drinking water that poses no significant health risk if consumed for a lifetime. PHGs are developed and published by OEHHA (Health and Safety Code Section 116365) using current risk assessment principles, practices and methods.
Feb 1, 2019: The Human Right to Water in California
The draft report was released January 3 with a 30‑day public comment period that was scheduled to close on February 4, 2019.  OEHHA has received requests from the Association of California Water Agencies and the California Municipal Utilities Association seeking an extension of the comment period.  OEHHA hereby extends the public comment period until 5 p.m., Tuesday, February 19, 2019.