If you enjoy spending time in the great outdoors (or simply like to feel warm and cozy throughout the day), you’re probably a fan of synthetic fleece jackets. But what you might not know is that every time one of these items runs through the wash, it releases thousands of microscopic plastic fibers into the water supply. These microfibers end up being eaten by fish and marine life – where they eventually end up back on our plates.
A study last year from the University of California Santa Barbara, in collaboration with the clothing company Patagonia, shows that every time polyester fleece jackets are run through the wash without detergent, up to 2 grams of these fibers could be shed. It’s worse for top-load washing machines, which release seven times more fibers than the front-load variety.
Unlike clothes dryers, which can capture loose fibers in lint traps, loose material in washing machines ends up simply being washed down the drain. Unfortunately, these microfibers are so small that wastewater treatment plants can’t filter them out. Instead, they end up being released into the environment, where they’re eaten by wildlife.
Are these microscopic bits of plastic harmful when ingested? It’s not entirely clear. Some studies have show certain species can’t cope well with the microfibers: water fleas who inadvertently eat fleece fibers are more likely to die, and common crabs that have ingested the tiny bits of plastic eat less food overall. But further research is needed to show if humans who eat fleece-filled seafood suffer any ill effects.
Unfortunately, short of avoiding fish altogether, it’s impossible to know whether you’re ingesting microfibers or not. For now, the only real solution is to either avoid washing your fleece when possible, or rig your washing machine with a filter to catch microfibers before they enter waterways. Sadly, that won’t do much unless everyone who wears synthetic fleece takes this advice to heart.