Airborne microfiber capture: secondary filtration a solution to filter microfiber emissions from clothing dryers

Household clothes dryers are a significant but often overlooked source of airborne microfiber pollution. Building on previous research documenting dryer-related microfiber emissions, this study evaluates the efficacy of secondary dryer filtration systems in reducing microfiber emissions. We tested three commercially available filters in a controlled laboratory setting, assessing reductions in microfiber mass, count, and size distribution. Results show that filters reduced the number of airborne microfiber emissions. The Duct Filter captured an average of 44% of microfibers emitted to air by count, compared to the indoor vents which captured 81% (Indoor Filter 1) and 70% (Indoor Filter 2) by count. Given the increasing concerns over microplastic pollution in environmental and human health, implementing secondary filtration in dryers presents a viable mitigation strategy to reduce microfiber emissions. This study provides critical data to inform industry standards and potential policy interventions aimed at reducing microfiber emissions at the source.