Synthetic fleece jackets and pullovers are a lifesaver for many outdoor adventurers who seek to hike and enjoy the outdoors in utmost comfort. Each wash of these clothes, however, translates to thousands of microfibers getting released into the environment, agricultural lands, and our food, the NPR has warned in a report.

Microscopic plastic fibers, or microfibers in short, appeared to be one of the most prevalent plastic debris materials found in animals as well as environmental samples, according to University of Toronto ecologist Chelsea Rochman.

How Microfibers From Fleece Jackets Migrate To The Environment

"I have no doubt that every time I eat oysters and mussels I eat at least one microfiber," said Rochman in the report, studying the presence of microplastics in marine habitats. "I see dust in the air and we inhale that. The question is, at what point does it become a problem? Here, the benefits outweigh the costs."

Synthetic microfibers have been detected in so many things, including arctic waters, fish caught off the California coast, and even table salt in China. These plastic materials shorter than a millimeter and composed of synthetic polymers make up a staggering 85 percent of human debris on the globe’s shorelines.

Researchers are delving deeper into the matter, with groups such as one from University of Georgia initiating a study on microplastics on the Georgia coast. Their results are expected to be published by early 2018.

And then there’s the matter with fleece sweaters.

Microfiber-containing jacket manufacturer Patagonia partnered with a team from University of California, Santa Barbara last year to study how much microfiber is released in washing bins. They ran branded and off-brand polyester fleece jackets through detergent-free wash to determine the mass of microfibers being shed every time.

The results: each jacket wash unleashed up to 2 grams of microfibers, and the release climbs to seven times more when a top-load washing machine versus a front-load one was used. These findings were discussed in the journal Environmental Science and Technology in September 2016.

Lead author Patricia Holden explained that the dryer trapped excess fuzz in the lint filter, while the microfibers are carried down the drain in the washer.

If one wonders where all these microfibers go, they actually end up in wastewater treatment plants, which are incapable of filtering them out and thus release them into the environment at large.

How Are They Exactly Harming Human Health?

While it is clear that the fibers reach our surroundings, it still takes research to know how these synthetic fibers exactly affect our health and wildlife.

According to previous studies, microfiber intake causes greater deaths in water fleas, as well as makes crabs consume less food than usual.

“If you’re eating fish, you’re eating plastic,” warned Gregg Treinish, who founded the nonprofit group Adventurers and Scientists for Conservation. He said there is yet to be a proven causality between the fibers and health problems, but that he does not want to spend more years consuming the food and being eventually told it carries dangers.

The short-term solution, experts advised, is to wash fleece clothing less frequently. One may also rig the washing machine with a filter for septic systems with the goal of capturing microfibers before they roam free in the waterways and the environment.