Interest, but no consensus, on microplastics at Senate hearing

A U.S. Senate panel heard calls on Feb. 27 for stepped up regulation and research around microplastics, but lawmakers seemed split on how to turn the science they were reviewing into policy.

Sen. Alex Padilla, D-Calif., for example, opened a Washington hearing before the Environment and Public Works Committee noting concerns about ubiquitous plastic microparticles in drinking water, and suggested an early-stage regulatory approach his state was taking could be a model.

"These findings should alarm us folks, alarm us into action," Padilla said. "Just how pervasive are these microplastics in the water that we drink?

"I'm proud to say that in California, we're trying to lead the way in trying to answer the question, as the first government in the world to set requirements for testing microplastics in drinking water," he added.

But Sen. Cynthia Lummis, R-Wyo., said that while there's "considerable public interest" in the topic, the science is not clear.

Similarly, Sen. Markwayne Mullin, R-Okla., told the hearing, titled "Understanding the Presence of Microplastics in Water," he was worried about burdening local water treatment plants with microplastics regulations when the science is uncertain.

Lummis said lawmakers should be cautious, given other pressing challenges municipal water plants must manage, like PFAS and lead contamination, she said.

"The consensus on microplastics and their effect on human health is that there really is no consensus, so we need to start diving into this and understanding it better as members of the U.S. Senate," she said.

Lummis noted that the federal Safe Drinking Water Act currently sets safe levels for more than 90 substances, including arsenic, lead, asbestos and mercury, focusing on substances that "are proven to harm human health."

For the moment, that does not include microplastics.

"The contaminants on this list did not appear overnight," Lummis said. "Generally, the process of adding contaminants to the national primary drinking water regulation is thorough, rigorous and multifaceted. It is a years-long process based on solid scientific data."

Still, there was support for stepped up research and regulatory activity around microplastics.

Witnesses at the hearing praised the approach of California's state government, in response to a question from Lummis about what policies "would give the biggest bang for the buck."

"I would give some credit to the state of California, which I believe is doing a very good job of approaching this topic," said Brent Alspach, vice president and director of applied research at water industry consulting firm Arcadis. "When the state passed its bill to give regulators a mandate to look at this process, they didn't go in with a foregone conclusion that something should be done about microplastics, but with an open mind that it's an important question that needs to be addressed."

Alspach, who said he's active on microplastics research within the American Water Works Association, said California set up definitions of microplastics and standardized methods for testing and monitoring, building data that, in time, will help make health assessments for drinking water safety.

"When their monitoring program has run its course, we hope there will be enough information between the occurrence data, the treatability data and the toxicity data to understand whether or not microplastics need to be looked at in the drinking water treatment context," Alspach said.

Other witnesses, however, cautioned that governments can't solve the problem by focusing on cleanup at water treatment plants.

Instead, they said effort should be directed toward preventing plastics from leaking to the environment in the first place and toward making plastics from safer chemicals so they don't produce toxic microparticles when they break down.

"I think real solutions to this problem are much more upstream," said Sherri Mason, director of sustainability at the Penn State University Behrend campus in Erie, Pa.. "I point to source reduction and extended corporate responsibility and a waste and recycling plan."

Susanne Brander, an associate professor at Oregon State University, said the ongoing United Nations plastics treaty talks should lead to policies to reduce the number of polymers used and simplify their chemical makeup.

"The toxicity of the polymers and the products that are being used, or the chemicals that are being used to produce those products, that needs to be tackled first," Brander said. "We have been relying on so many different combinations of chemicals, that even if something is fully biodegrading, that doesn't mean that it's not releasing those toxic compounds into the environment."

As well, Mason said more research should be directed to making plastics with fewer toxic chemical inputs, noting the benefits of plastics in cars and appliances.

"Cars are much more fuel efficient because of the plastics that have been used in them," Mason said. "But coming up with a biodegradable, nontoxic plastic would be really helpful there. I think that is the future."

Sen. Dan Sullivan, R-Alaska, the main Republican author of both the Save Our Seas plastics marine debris laws passed in 2018 and 2020, said he "did not disagree" with Mason and Brander's points around developing biodegradable and less toxic materials.

He said he thought it would lead to more profit for companies.

"If you're the company that has cracked the code on less toxicity and full biodegradability, A, I think that would be very good for the environment, but B, that company's probably going to profit," Sullivan said.

Some advocated product specific solutions.

Sen. Jeff Merkley, D-Ore., pointed to legislation in his home state and in California to require filters on washing machines to catch plastic microfibers from clothes.

He also noted legislation he introduced in January in Washington to study how microplastics impact agriculture, such as when the biosolid sludge byproducts from wastewater treatment plants are used as fertilizers on farms.

"We need to stop microplastics and nano plastics from getting into the water in the first place, and how to filter them out when they already exist," said Merkley, who also spent considerable time in a Senate hearing in 2022 quizzing experts on microplastics.

Echoing Merkley, Brander suggested a focus on clothing, pointing to research that the United States has "among the highest prevalence of microfibers in its drinking water," which she linked to use of "fast fashion" plastic fiber clothing.

She noted evidence of microplastics harming wildlife, and concerns about its presence in people.

"Formulations of plastics are estimated to use upwards of 13,000 chemicals, and microplastics are widely documented to harm aquatic and terrestrial wildlife," Brander said. "They also cause adverse effects in mammals and particle presence is now confirmed in the human heart, placenta and lung tissue, as well as in circulation in the blood stream."

Mason said that while there are gaps in the science, there's enough knowledge to raise warning flags.

"Understanding the impacts of the plastic polymers themselves is the real knowledge gap currently, but initial studies have shown connections to inflammation, oxidative stress, Alzheimer's and other neurological diseases," she said. "While we don't know everything, what we do know is concerning and water, the necessary elixir of life, is a primary means for the movement of microplastics and nanoplastics into people."

Brander said lawmakers should look to the Clean Water Act "as the most direct route" to regulate microplastics, but Alspach said it's not clear yet if they are toxic under the Safe Drinking Water Act.

Oklahoma's Mullin said more research should be done on microplastics but he also warned against what he saw as Congress putting undue burdens on city-run water systems.

"As we're moving forward, looking at microplastics, we have to be careful that we're not getting ahead of, as we would say, the science … and burden these municipalities that are trying to meet today's regulations, to chase something that we don't know the conclusion of, if it's actually causing… harm or if it's causing harm at all."

"I just caution all of us to understand that we have a lot of research to do," said Mullin, who is the top Republican on the Senate subcommittee within the Environment and Public Works Committee that has put the most attention on plastics.

Both he and Lummis quizzed panel witnesses on the costs that water treatment plants might be required to take on to deal with microplastics, and Lummis asked how small communities in rural states like Wyoming could do a cost-benefit analysis.

"We just need more research to be able to even answer that question," said Alspach, the water treatment consultant. "I don't believe at this point that utility in Wyoming could do a meaningful cost-benefit analysis without much more information about what that analysis would ultimately tell them."

But other witnesses pointed to research like a study in January that estimated $250 billion in annual medical and other costs from endocrine disrupting chemicals used in plastics in the United States.

And one senator, Rhode Island Democrat Sheldon Whitehouse, said he wanted to attend the next round of plastics treaty negotiations, in Canada in April, and asked panelists what messages he should be taking to U.S. diplomats there.

No clear consensus seemed to emerge among senators at the hearing about what policy steps to take around microplastics in water, but there was general support for more research.

Lummis, the senator from Wyoming, suggested interactions with a family member were changing her thinking.

"My daughter is a little obsessive about the containers she uses in her house for my grandchildren," Lummis told the hearing. "I thought she was being a little obsessive compulsive. And now I know she's not. This is a real thing, a real concern."