Toxicity Testing Guidance Documents

The Ecotoxicology Program, working with Mike Hopper, Texas Tech University; Brian Anderson, UC Davis, and Mike Anderson, California Dept. of Fish & Game, has prepared two guidance documents on toxicity testing methods. The first, initially posted in Spring, 2004, surveys freshwater and marine toxicity testing methods. The second, posted in December, 2008 for the first time, reviews soil toxicity testing methods and related bioassessment issues. These documents were developed as a service to the scientific community, in keeping with our mission of developing tools and technical resources to advance the science and practice of ecological risk assessment.

Environmental managers responsible for assessing the ecological integrity of aquatic and terrestrial resources in California rely on a number of assessment tools including chemical analysis of soil or water, animal or plant tissues; biological assessments; and toxicity tests. Toxicity tests are an important component for assessing the impact of chemicals on ecosystems because they indicate toxic effects of complex chemical mixtures. In toxicity tests, groups of selected organisms are exposed to test materials (water, sediment, or soil samples) under defined conditions to determine potential adverse effects. These two documents provide an overview of the numerous standardized toxicity test protocols. Additionally, the soil toxicity guidance document reviews bioassessment tools and methods that can play a critical role in the ecological risk assessment process.

Please refer questions or comments on either document to Barbara Washburn atbarbara.washburn@oehha.ca.gov(link sends e-mail).