Study Finds Average Laundry Load Releases Nearly One Million Microfibers

It’s common knowledge that up to two-thirds of a garment’s carbon footprint occurs after purchase, thanks to the environmental impact of washing and drying, and a new study by Plymouth University in the United Kingdom has put a number on how many microfibers are released into the ocean with each laundry load.

The research paper, soon to be published in Marine Pollution Bulletin, discovered that more than 700,000 tiny fiber particles could be released into waste water during each wash of synthetic fabrics in a domestic washing machine.

“The quantity of microplastic in the environment is expected to increase over the next few decades and there are concerns about the potential for it to have harmful effects if ingested. But while the release of tiny fibers as a result of washing textiles has been widely suggested as a potential source, there has been little quantitative research on its relevant importance, or on the factors that might influence such discharges,” the paper’s authors explained.

Led by PhD student Imogen Napper in conjunction with Professor Richard Thompson, the research group washed a series of polyester, acrylic and polyester-cotton items at standard temperatures of 30 degrees Celsius and 40 degrees Celsius (86-104 degrees Fahrenheit), using a range of detergents and fabric conditioners. They then examined the mass, abundance and size of fibers extracted from the waste water.

The results: an average washing load of 6 kilograms could release an estimated 137,951 fibers from polyester-cotton blend fabric, 496,030 fibers from polyester and 728,789 from acrylic. Interestingly, the poly-cotton blend shed the fewest fibers, but bio-detergents and conditions caused fabrics to release more fibers.

While the study confirms earlier work at Plymouth University that laundry is a major source of microscopic fibers within the aquatic environment, professor Thompson pointed out that its findings aren’t meant to invoke a ban similar to the one affecting the use of microbeads in cosmetics.

“In that case, one of the considerations guiding policy intervention was the lack of clear societal benefit from incorporating microplastic particles into the cosmetics, coupled with concerns about environmental impacts,” he wrote. “The societal benefits of textiles are without question and so any voluntary or policy intervention should be directed toward reducing emissions either via changes in textile design or filtration of effluent, or both.”

Earlier this year, a study by outdoor clothing company Patagonia found that the age of synthetic apparel as well as the washing machine model are key factors for microfiber pollution. As a result, the company’s Patagonia Plastics Project will assess its own clothing’s environmental impacts in an effort to help decrease microfiber pollution.