Study gauges public's willingness on microplastic interventions
Laundry is a major source of microplastic pollution into the environment, and in-line washing machine filters are one potential solution for preventing fibers from entering waterways. But how likely would people be willing to pay for them?
Portland State researchers surveyed a sample of registered voters and environmental interest groups in Oregon to gauge respondents' general knowledge and concerns surrounding microplastics, as well as their willingness to pay for high-efficiency washing machine filters. The researchers hope the study can provide greater insights for policymakers. Currently, is under committee consideration, which would require new clothes washers sold in the state to have a microfiber filtration system by 2030.
Findings in the journal Microplastics and Nanoplastics show that less than a quarter of all 664 respondents would be willing to pay full price for a high-efficiency external filter, indicating the need for filters to be included in point of sale purchases rather than after the fact.
A limited-scale early adopter program may be a feasible transitional implementation option. Up to 20% more people support filter adoption on their existing washing machines if part of the cost were covered by a government subsidy.
"Washing machines are a major source of microfibers and microplastics entering our wastewater systems and ultimately our waterways," said Elise Granek, study co-author and a professor of environmental science and management at PSU. "Mandating washing machine filters at the point of sale has been identified as a tool to significantly reduce this source of microplastics entering aquatic environments."
Still, the researchers say the filters are not a full solution on their own and policymakers must continue to give attention to source reduction, investment in plastic alternatives and improved industry regulations.
The study's authors include Amanda Gannon, a graduate of PSU's master's in environmental management program; Elise Granek and Max Nielsen-Pincus, professors of environmental science and management at PSU; and Luke Harkins, chief of staff for Oregon Rep. David Gomberg.
More information: Amanda Gannon et al, Perceptions about potential microplastic interventions: a study on knowledge, concerns, and willingness to pay, Microplastics and Nanoplastics (2025).
Provided by Portland State University
