Household dryers are a significant source of microfiber pollution, according to a new study conducted by scientists at the Desert Research Institute (DRI) in partnership with the nonprofit Keep Tahoe Blue. The research, published in Environmental Toxicology and Chemistry on September 3, estimates that more than 3,500 metric tons of microfibers are released annually by household dryers in the United States.
The study involved volunteers from the Lake Tahoe region, who installed mesh catchment systems on their home dryer vents for three weeks. They reported the materials in each dryer load using the Citizen Science Tahoe smartphone app. After the study period, the mesh covers were mailed back to DRI for analysis.
The findings show that both natural fibers such as cotton and synthetic fibers like polyester are released from dryers. These microfibers can carry chemicals and dyes used in fabric treatment into the environment. Monica Arienzo, Director of DRI’s Microplastics and Environmental Chemistry Lab and lead author of the research, stated: “This study expands our understanding of how textiles are breaking down under typical household conditions. Because of the ubiquity of microfibers and their ability to contribute other chemicals to the environment, it’s important for us to understand ways to reduce microfibers at the source. Household dryers could be one simple place to address them.”
Synthetic fabrics made up more than half of global fabric production in 2023. Both synthetic and natural fibers may be treated with chemicals such as dyes, flame retardants, PFAS for water repellency, and formaldehyde for wrinkle resistance. Scientists are still studying the environmental and health impacts of these substances.
In U.S. households, most dryers vent hot air outside without filters capable of catching microfibers after the lint filter. Other dryer types, more common outside the U.S., may have different emissions profiles.
The amount of microfiber collected varied depending on dryer model, age, and fabric condition. Based on volunteer data and national dryer use statistics, researchers estimate that 3,543 metric tons of microfibers are released annually across the country—2,728 metric tons from natural fabrics and 460 metric tons from synthetics.
Marilee Movius, Sustainable Recreation Manager for Keep Tahoe Blue, commented: “This volunteer-fueled research adds to our knowledge of pollution sources, like dryer vents, which can impact the ecosystems we cherish and depend on. It also shows us how small behavioral changes—such as installing more efficient lint filters or air drying our clothes—can reduce microfiber emissions and protect the natural environment, Lake Tahoe, and ourselves.”
The full study is available at Environmental Toxicology and Chemistry (https://doi.org/10.1093/etojnl/vgaf222). The U.S. Environmental Protection Agency provides additional information about microfiber pollution in its fact sheet (https://19january2021snapshot.epa.gov/sites/static/files/2020-07/documents/article_2_microfibers.pdf).
The research team included Monica Arienzo (DRI), Meghan Collins (DRI), Emily Justice Frey (Keep Tahoe Blue), Marilee Movius (Keep Tahoe Blue), Laura Patten (Keep Tahoe Blue), Angelique DePauw (DRI), and Rachel Kozloski (DRI).
DRI is a nonprofit research institute based in Nevada with over 600 staff members working across campuses in Reno and Las Vegas. In 2024 alone, DRI conducted more than $52 million in sponsored research focused on improving human and environmental health.
Keep Tahoe Blue is a science-based organization dedicated to protecting and restoring Lake Tahoe through research, advocacy, and citizen engagement.