California Approves World’s First Testing Requirement for Microplastics in Drinking Water

On September 7, California’s State Water Resources Control Board unanimously approved a proposed policy handbook establishing a standard method for testing and reporting drinking water supplies for microplastics. The development of this new testing method was required by a California state law passed in 2018. Under this law, California must use this method to test drinking water for four years. The policy handbook outlines a two-phase iterative approach for monitoring, with each phase lasting two years along with an interim period between the two to “allow for State Water Board staff to assess results from the first phase and plan the second phase of monitoring accordingly.” The plan states that, for both phases, public water systems and/or wholesaler providers will be ordered to monitor for microplastics in both source waters and/or treated drinking water.