SFEI is studying dryer emissions to find out if clothing dryers are a significant source of microplastic pollution in the San Francisco Bay. The study will measure the dryer emissions from single-family homes, laundromats, apartment buildings, and other shared laundry facilities. The study will also evaluate the efficacy of commercially available secondary dryer filters (screens installed on a dryer's exhaust duct) in capturing microplastic fibers before they enter the environment. The dryer study will contribute to the Statewide Microplastics Strategy led by the California Ocean Protection Council (OPC) to investigate the sources and pathways of microplastics and develop action plans for combatting microplastic pollution.
In California's most comprehensive microplastics pollution study, SFEI found that almost half of the microplastics in urban stormwater runoff are fibers. Microplastic fibers are tiny thread-like pieces of plastic less than 5mm long (smaller than a grain of rice) that are shed from clothing, towels, and other everyday household products made from synthetic fabrics. During the drying process, fibers that aren't captured by the lint trap are vented outdoors, settle on nearby surfaces, and wash into stormwater collection systems or are carried directly to waterways by the wind. While air drying is common in most parts of the world, clothing dryers with outdoor ventilation are the standard in the United States. In the Western United States, most urban runoff is discharged directly into waterways without receiving treatment. SFEI found that storm-driven urban runoff transports hundreds of times more microplastics into the aquatic environment than wastewater, which makes a stop at a treatment plant before being discharged into the San Francisco Bay.
Findings about dryer-born microplastic pollution in the San Francisco Bay will guide California's Statewide Microplastics Strategy. By monitoring emissions from dryers and learning about the laundry habits of people around the Bay, SFEI hopes to understand how much microplastic fibers the average Bay Area household emits, estimate how much dryer-emitted microplastic fiber is entering the Bay, and compare this to other sources of microplastics pollution. Here's how you can help SFEI combat microplastic pollution in the Bay:
- Take a one-minute survey to tell us about your laundry habits
- Sign up to let us measure dryer emissions in your home, apartment building, or dorm. Selected participants will receive a $25 gift card!
- If you are a laundromat owner, sign up to let us measure dryer emissions in your laundromat. We will be on-site for 1-2 hours to monitor dryer emissions. Participating laundromat owners will receive a $200 gift card!
Your survey responses and data collected from your home or business are anonymous. They will be pooled with others to help us understand typical dryer emissions across single-family homes, shared laundry facilities, and laundromats. Your anonymous participation will help SFEI improve microplastic monitoring, prevention, and mitigation in the San Francisco Bay Area and beyond!
Read more about the dryer study.
