Microplastics in Drinking Water: California’s Regulatory Actions

Drinking Water
Oral Presentation

Prepared by S. Coffin
State Water Resources Control Board, 1001 I Street, Sacramento, CA, 95814, United States

Contact Information: [email protected]; 916-323-0375


Plastic is becoming increasingly more abundant in the environment, causing concern amongst scientists and regulators due to the potential harm towards humans. In 2018, the California Legislature passed Senate Bill 1422 which requires the California State Water Resources Control Board (State Water Board) to adopt a definition of microplastics in drinking water, adopt a standard methodology to measure microplastics in drinking water, adopt requirements for four years of testing and reporting of microplastics in drinking water, consider issuing a notification level or other guidance to aid consumer interpretations of the results of the testing, and accredit laboratories to analyze microplastics. State Water Board staff, in collaboration with additional agencies and research institutions, are conducting studies and compiling information to comply with these legislative mandates. This presentation will provide an overview of the State Water Board’s ongoing processes to regulate microplastics in drinking water, including considerations of the definition of microplastics, known human health effects of microplastics, microplastics method standardization and validation efforts, and upcoming plans and actions regarding microplastics in drinking water.