Microfibers: Fabric softeners reduce tumble dryer soiling

Tumble drying clothes causes microfiber soiling, but using a tumble dryer sheet and anti-wrinkle fabric softener almost cuts that in half

Through Chen Ly

Drying clothes in the tumble dryer releases just as many microfibers into the air as washing them, but if you switch your fabric softener and use a dryer sheet, this could be drastically reduced.

Microfibers are tiny thread-like particles that become detached from our clothes, mainly during washing and drying. They can get into the air, soil and water and be potentially harmful to people and wildlife.

Neil Lant of consumer goods company Procter & Gamble and his colleagues tested the various factors that can affect the release of microfibers during tumble drying. They washed loads of laundry with 10 cotton and 10 polyester t-shirts using different brands of detergent, fabric softener and dryer sheets popular in Europe and North America. They then dried these garments in vented dryers, which emit moist warm air through a tube to the outside air, and measured the amount of microfibers released.

They found that using regular fabric softeners reduced microfiber emissions by a maximum of 22 percent, depending on the product and dosage, but using anti-wrinkle fabric softeners by up to 36 percent.

Fabric softeners help hold the fibers together, making them more likely to get caught in the dryer’s lint filter, Lant says. Anti-wrinkle conditioners smooth out creases in clothing, reducing friction between them, resulting in less microfiber release.

Using tumble dryer sheets that collect fibers reduces microfiber release by up to 35 percent. Using an anti-wrinkle fabric softener and a tumble dryer sheet together reduced microfiber emissions by 45 percent. Reducing the pore size of the lint filter also helped reduce fiber emissions.

While these products can reduce microfiber pollution in the short term, tumble dryer manufacturers need to develop better filtration systems, Lant says. It would also be better to switch away from vented dryers and towards condenser dryers, which don’t leach microfibers into the environment, he says.

“There will be a lot of technology that we can put into tumble dryers that would help prevent microfiber release,” says team member Kelly Sheridan of Northumbria University in Newcastle, UK. “But nothing will help quite like stopping the release of fibers from clothing in the first place, and further research will help us understand how.”

“Indeed, this is a very comprehensive study that further confirms our observation that tumble dryers can emit microfibers into the atmosphere,” says Kenneth Mei-yee Leung of the City University of Hong Kong. The researchers collected microfibers using a mesh with 0.2-millimeter holes, so smaller microfibers would not have been counted in the study, he says. “Your method is likely to underestimate the total amount of microplastics released into the air.”

Magazine reference: Plus oneDOI: 10.1371/journal.pone.0265912