Two aquatic scientists said Thursday that legislation in Washington state to phase out personal care products made with plastic microbeads wouldn’t actually reduce water pollution if the plan only requires companies to substitute beads made of biodegradable plastic.
A California-based environmental group had previously raised that concern about House Bill 1378, which would ban personal care products containing the plastic particles by 2020. The microbeads are commonly used for their exfoliating properties in products such as facial scrubs, body washes and toothpastes.
"We don’t believe there is such a thing as biodegradable plastic," said Britta Denise Hardesty, a research scientist with the Commonwealth Scientific and Industrial Research Organisation in Australia. "What tends to happen is they break down into smaller and smaller particles."
The small particles can slip through shower drains and end up in rivers and oceans, where they absorb toxic chemicals and get ingested by fish and plankton, Hardesty said.
As written, the proposed ban on products with exfoliating microbeads would apply to products containing nonbiodegradable particles less than five millimeters in diameter.
Raechel Waters, an oceanographer who now is a senior project developer for Paul Allen’s Vulcan, Inc., asked members of the House Environment Committee to amend the legislation to only allow materials that are naturally biodegradable, which she said would exclude microbeads made of biodegradable plastic.
"Essentially they just don’t biodegrade quickly enough," Waters said. "There are also concerns that they don’t biodegrade completely."
Naturally biodegradable alternatives to compostable plastic microbeads could include sugar, salt or oatmeal, she said.
The Personal Care Products Council, a trade group representing more than 600 companies, is supporting the microbead ban as written.
"Concerns that the personal care industry will reformulate with materials that degrade only at temperatures that would not be expected in the natural environment are not true," a statement from the council said.
The statement issued Thursday by the trade group stopped short of saying the organization would support amending the bill to ensure the ban extends to microbeads made of biodegradable plastic.