Just one pair of blue jeans sheds a staggering 56,000 microfibers per wash on average, according to new research, and that immense amount of microscopic waste seems to be accumulating in the Arctic.
Every time a piece of clothing is washed, small fuzzy bits come loose and go out with the wash. These “microfibers,” tiny strands of organic or synthetic material less than five millimeters long, flow out with the wastewater into our rivers, oceans and environments. Together with microplastics—teeny pieces of plastic—these miniscule pieces of our built environment are quickly becoming one of the most prevalent sources of pollution in our oceans, as Rachel Kaufman reported for Smithsonian magazine in 2016.
Scientists have found these micro-particles in our soils, mountaintops, floating in the ocean breeze and in a cup of tea. Now, new research published this week in Environmental Science & Technology Letters demonstrates that microparticles are leeching out of denim as well.
“Unfortunately, the results are not surprising to environmental scientists; they are even expected,” Caroline Gauchotte-Lindsay at the University of Glasgow, who was not involved in the study, tells New Scientist’s Chris Stokel-Walker. She adds that this paper is important, because it looks at natural microfibers, mainly cotton, as opposed to synthetic ones. In fact, the team found jeans slough off about ten times as many microfibers than a polyester fleece jacket releases after a wash cycle, reports Dharna Noor reports for Gizmodo.
A team of researchers from the University of Toronto were inspired to study blue jean microfibers when they were collecting microscopic samples in the Canadian Arctic Archipelago and the Great Lakes, reports Gizmodo.
“Strangely, we all reported finding blue fibers in the samples,” University of Toronto environmental scientist Miriam Diamond, co-lead author on the paper, tells Gizmodo in an email. “We wondered if these prevalent blue fibers could be from blue jeans (what else in our wardrobes have so many blue fibers?).”
The researchers examined sediment samples from shallow lakes near Toronto, the Huron and Ontario Great Lakes, and the deep-sea Arctic. They used microscopes and a technique called Raman spectroscopy to identify blue jean fibers by their signature indigo dye, and to differentiate the “anthropogenically modified cellulose” of blue jeans from other polyester or nylon fabrics, reports Matt Simon for Wired magazine. .
Worryingly, blue jean fibers cropped up in every sample in large numbers—even in samples from far-off regions like the Arctic. Speaking to Wired, co-lead author Sam Athey explains that their findings track with previous studies, which have shown that ocean currents can move microfibers incredibly long distances across the planet.
“It does suggest that they ended up there through long-range transport processes. Whether they're oceanic or atmospheric—we don't know exactly,” says Athey.
As Marcus Eriksen, a researcher who studies marine pollution, tells Wired, the study’s findings may support another theory researchers have that the Arctic could be an end point for subsurface currents, he explains.
“What you have is the deep-water conveyor belt, which takes neutrally buoyant debris around the world, ending in the Arctic," says Eriksen. "Now we’re finding really high sediment loads of microplastics in Arctic sediments.”
One study in 2016 found that half of the people living in Canada wear jeans almost every day, and the average Canadian washes their jeans after two wears. Researchers say that they hope this most recent study reminds the average person that if anything, they don’t need to wash their jeans quite as often.
“The thing is, there’s so many people on the planet—there’s just too many of us,” Diamond tells Wired. “And I think what’s astonishing is how many of us wear jeans. It’s not an indictment of jeans—I want to be really clear that we’re not coming down on jeans. It’s just a really potent example of human impact.”