Household dryers release thousands of tonnes of microfibres into the air each year, making them a major but often overlooked source of pollution. The study found that fibres from both natural and synthetic fabrics carry textile dyes and chemicals into the environment, underscoring dryers as important targets for reducing microfibre emissions at source.
- Researchers estimated more than 3,500 metric tonnes of microfibres emitted annually across the United States from household dryers, based on measurements gathered from real homes during normal laundry cycles.
- Natural fibres such as cotton dominated the material collected on vent meshes, while polyester, fleece, and other synthetics were also present in substantial quantities across recorded loads.
- The research was conducted by scientists from the Desert Research Institute, a Nevada-based environmental research organisation, and Keep Tahoe Blue, an environmental nonprofit focused on protecting Lake Tahoe.
- DRI authors included Monica Arienzo, Meghan Collins, Angelique DePauw, and Rachel Kozloski, leading laboratory analyses and synthesis of findings from the citizen-science mesh samples.
- Keep Tahoe Blue contributors were Emily Justice Frey, Marilee Movius, and Laura Patten, coordinating volunteer recruitment, protocol adherence, and data submissions through the Citizen Science Tahoe application.
THE STUDY: Researchers used a citizen-science approach to measure how household dryers release microfibres into the air during regular use. Volunteers in the Lake Tahoe region installed mesh covers over outdoor dryer vents for three weeks, recording the type of fabrics dried. The collected material was weighed, analysed for composition, and compared across households to estimate national-scale emissions from typical home dryers.
- Six volunteers from the Lake Tahoe region participated, installing mesh covers over their dryer vents to capture emitted fibres for laboratory weighing and chemical analysis.
- A total of seventy-six dryer loads were recorded with mesh covers, and thirty-eight additional loads without them to compare results.
- Dryer model, age, and fabric condition influenced the weight of captured fibres, producing wide variation across households.
- The study generated new community-collected data on microfibre emissions from household dryers, expanding available information on how domestic appliances contribute to fibre release.
THE FINDINGS:Laboratory results confirmed that dryers release both natural and synthetic microfibres in significant quantities. Natural fibres dominated, accounting for roughly four-fifths of total emissions, with synthetics contributing the remainder. Emission levels varied widely, influenced by dryer design, model age, and the condition of the fabrics being dried during testing across participating households.
- Researchers estimated that household dryers in the United States emit about 3,543 metric tonnes of microfibres each year.
- Of this total, approximately 2,728 metric tonnes came from natural fabrics such as cotton, while 460 metric tonnes originated from synthetic materials.
- The total reported emissions were slightly higher than the sum of the natural and synthetic categories in the dataset.
- Natural fibres such as cotton dominated the material collected on the dryer-vent meshes, while polyester and other synthetics were also present.
- Most dryers in the United States are vented tumble models that release air outdoors, while condenser and heat-pump dryers used elsewhere may have different emissions.
- The scale of estimated emissions — roughly thirty times the weight of the Statue of Liberty — illustrates the magnitude of the issue in everyday settings.
THE BIGGER PICTURE: The findings reinforce growing evidence that both washing and drying release large quantities of microfibres into the environment. While washing machines primarily discharge them through wastewater, dryers emit fibres directly into the air through external vents.
- The study adds complementary evidence that airborne emissions from dryers represent an equally significant yet under-measured pathway.
- Variation among dryers and fabrics was linked to differences in model, age, and fabric condition observed across households.
- Combined washing and drying impacts show that textile-fibre pollution arises from everyday domestic activity rather than isolated industrial processes.
WHAT THEY SAID
This study expands our understanding of how textiles are breaking down under typical household conditions. Because of the ubiquity of microfibres and their ability to contribute other chemicals to the environment, it’s important for us to understand ways to reduce microfibres at the source. Household dryers could be one simple place to address them.
— Monica Arienzo
Director, Microplastics and Environmental Chemistry Lab
Desert Research Institute
This volunteer-fuelled 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 behavioural 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.
— Marilee Movius
Sustainable Recreation Manager
Keep Tahoe Blue
