The mission of the Ecotoxicology Program within the Office of Environmental Health Hazard Assessment (OEHHA) is to advance the science and practice of ecological risk assessment (ERA). We focus on developing tools and technical resources to assess the impacts of chemical, physical, and biological stressors on ecosystems. Our current focus is on aquatic ecosystems.

Our Program was established in 1993 with the goal of applying tools from the developing field of human heath risk assessment to address the risks caused by chemicals on California’s ecosystems. In 1998, the US EPA adopted a set of Guidelines for “evaluating the likelihood that adverse ecological effects may occur or are occurring as a result of exposure to one or more physical, chemical, or biological stressors”. ERA is based on a simple three-step process which includes a) identifying the problem or stressor(s) of concern, b) analyzing the stressors by characterizing their exposure and ecological effects, and c) characterizing risk using a variety of methods. The work of the OEHHA Ecotoxicology Program is currently focused on applying this approach to understanding risks to the State’s aquatic resources.

To inquire about our Program, contact

Reports, Notices, Documents

Aug 31, 2016: CalEcotox Database
A compilation of physiological and ecological parameters and toxicity data for a number of California fish and wildlife species.
May 2, 2016: Dry Wells
OEHHA, the City of Elk Grove and a team of hydrologists are studying the potential environmental risks associated with the use of dry wells. The project aims to determine whether dry wells in combination with other low impact development (LID) practices are a cost-effective way to infiltrate stormwater and recharge the aquifer- without negatively affecting groundwater quality.
Mar 27, 2015: Ecotoxicology Resource Links
Extensive list of external sources of information for ecological risk assessment provided for informational purposes.
Jan 20, 2015: Dry Creek Watershed Assessment and Indicator Report
OEHHA is assisting the Dry Creek Conservancy (DCC) and the American Basin Council of Watersheds to gain a better understanding of the stressors in the Dry Creek watershed that have contributed to salmon declines over the past two decades. OEHHA is collecting environmental data and is using the Stressor Identification (ID) method developed by the US Environmental Protection Agency to identify impacts of urbanization and causes of impairment to the health of the watershed.