California taking closer look at microplastics

California, the first state in the U.S. to ban plastic bags, now wants to be the first government in the world to take a look at microplastics in drinking water.

Regulators at the State Water Board voted June 16 to open a multiyear review of microplastics in water supplies, including developing rules to measure it and potentially issue health guidelines.

While the state action is in its early stages, the plan is attracting a lot of attention from industry and environmental organizations who say it could pave the way for similar moves elsewhere.

"As the first regulatory agency in the world to specifically define microplastics in drinking water, the board decision will have far-reaching impacts," said Miho Ligare, plastics pollution coordinator with the San Clemente, Calif.-based Surfrider Foundation.

Board officials said much remains unknown around the science and what it may mean for human health. The unanimous vote by the five-member body is probably more akin to putting a toe in the water.

The June 16 vote adopted a preliminary definition of microplastics to meet a July 1 deadline set by a 2018 state law.

But there's more to come, such as plans to develop testing protocols by the middle of 2021, do four years of measuring and make those results public, also ordered by lawmakers in Sacramento.

Legislators who passed the law said they were concerned about studies of nearly 160 cities worldwide that found microplastics in 83 percent of samples and research noting microplastics in fish sold for consumption in California, New Jersey and Indonesia.

A report from the board's staff said it would be the first government agency in the world to try to define microplastics in drinking water, although others like the European Chemicals Agency are developing definitions for other uses.

"This is a fast-moving field," said Board Chairman Joaquin Esquivel. "I know there will continue to be robust discussion within the CalEPA family… around not just the definition but how we best regulate and understand plastics, both micro and macro, throughout the watersheds."

Plastics groups like the American Chemistry Council urged the board to adopt a narrower definition of microplastics.

ACC and other industry groups urged the water board to exempt biodegradable plastics and soluble polymers from their definition, as well as urged any monitoring program should not include polymers unlikely to be found in drinking water.

Having the monitoring program include polymers not likely in drinking water would be an unnecessary expense for water treatment facilities while not yielding any public benefit, said Brett Howard, a director with ACC's regulatory and technical division.

He also said defining microplastics has proven complex for the European Chemicals Agency.

"ECHA has been trying to develop a viable definition of microplastics, and not just in drinking waters, for years," Howard said. "A definition cannot be developed in the abstract or in a vacuum. It must be supportable by detection limits and the regulatory purposes its supports.

"California's proposal here goes well beyond the even lower limits suggested in Europe," Howard said.

But a scientist with the U.S. Environmental Protection Agency, testifying at the board hearing, endorsed the water board's actions and supported the definition of microplastics, including smaller particles and biodegradable plastics.

"The U.S. Environmental Protection Agency's Office of Research and Development supports the definition proposed by the California Resources Control Board in its entirety," said Kay Ho, an EPA environmental research scientist. "We are particularly pleased to see the inclusive nature of the definition regarding smaller-sized microplastics and the incorporation of biodegradable plastics."

She noted current research pointing to "biological activity" involving microplastics less than 1 micron as well as uncertainties around impacts of biodegradable plastics.

"There is very little known about the toxicity of the new class of biodegradable plastics, so understanding their presence in drinking water is reasonable, justifiable and proactive," she said.

Business groups are worried about overly broad definitions stifling innovation.

"We are concerned that such a broad, all-encompassing approach may not be in line with the approach of the European Union for these materials, and it could in that regard have some detrimental impacts on innovation and global companies' efforts to drive progress to more sustainable products," said Dawn Koepke, a lobbyist for the California Manufacturers and Technology Association in Sacramento.

But environmental groups compared microplastics to perfluorinated chemicals, which have been widely used for decades but now face increasing scrutiny.

"The industry convinced the U.S. for decades that PFOA and PFAS were safe, but we all know now what happened with this, now the entire world is contaminated with these forever chemicals," said Evelyn Wendel, executive director of WeTap, a public water advocacy group.

"Only recently have we been able to find the human health impacts of these chemicals," she said. "It appears now that microplastics are also ubiquitous and forever in our environment."

Environmental groups also pushed for a broad definition to include polymers used in things like tires and fabrics, since they can release particles into the environment.

"The public deserves to know what is in their drinking water," said Baani Behniwal, policy associate with Californians Against Waste.

The board defines microplastics as smaller than 5 millimeters, a size the agency said concerns scientists because they can be eaten by animals. It noted that other microplastics can be much smaller and only seen under a microscope.

It's the difficulty measuring the tiniest of them that prompted concern from some water treatment agencies.

The Southern California Alliance of Publicly Owned Treatment Works, for example, said it was worried that the board was adding nanoplastics, the smallest category of microplastics at less than one micron, into its definition with little notice.

"We haven't had time to evaluate the science and impact on our sector," said Steve Jepsen, executive director of the group. "This may be catching many of our stakeholders by surprise."

But the board staff argued in a presentation that the water treatment process can cause microplastics to fragment into smaller nanoplastics, potentially increasing the number of particles tenfold.

Agency officials said they remain several years away from any potential recommendations on human health impacts, given where the science is, and said they will revise their definitions again next year, ahead of the legislative deadline for testing protocols and starting to measure.

"We're years down the road from then understanding whether there's health impacts," said Darrin Polhemus, deputy director of the agency's division of drinking water.

The water board's work is part of a larger effort in California, the Statewide Microplastics Strategy, mandated by the Legislature. The state's Ocean Protection Council and the Southern California Coastal Water Research Program are also involved in that.