Premature or precautionary? California is first to tackle microplastics in drinking water. Photo by Cole Brookson courtesy of Rochman Lab California is about to set the world’s first health guidelines for microplastics in drinking water. Yet no one agrees how to test water for the tiny bits of plastic, or how dangerous they are. This story originally appeared in CalMatters.org, a nonprofit, nonpartisan media venture explaining California policies and politics. Pictured above: Microplastics collected in the San Francisco Bay Area are identified and labeled for research in a lab headed by Chelsea Rochman, an assistant professor at the University of Toronto. California is about to set the world’s first guidelines for microplastics in drinking water.