Microfibers: Tiny Plastics Have a Huge Impact on our Oceans

By Claire Dawson, Marc Hershman Marine Policy Fellow

Our oceans have a plastic problem: Every year, an estimated 8 million metric tons of plastic waste enter the world’s oceans from land. From a plastic patch in the South Pacific that is larger than Mexico, to fragments found in the guts of birds and other wildlife, all the way to the most remote islands on Earth covered in tidal trash: Humanity’s addiction to plastic plays out in upsetting myriad ways across our global ocean. According to the World Economic Forum, our oceans could contain more plastic than fish by 2050.

Marine debris litters a beach on Laysan Island in the Hawaiian Islands National Wildlife Refuge, where it washed ashore. Photo © U.S. Fish and Wildlife

Most of the waste consists of everyday items: bottles, caps, straws, wrappers and bags. Yet, another proportion of this waste is more invisible: microplastics, some as small as particulate matter. They travel the world’s oceans and are ingested at various levels of the food chain. Microbeads, the tiny plastics used in many cosmetic products, recently banned in the U.S., are one example. And we are just beginning to understand the extensive reach of another type of microplastic: microfibers from our clothing.

Example of microplastics. Photo © 5Gyres, courtesy of Oregon State University, used under CC by 2.0

Microfibers are smaller than one-fifth of an inch, sloughed off in our washing machines. About 40 percent of microfibers make their way through sewage treatment plants into our rivers, lakes and, eventually, the ocean. Why are these small fragments of fibers an issue in terms of plastic pollution? Unfortunately, much of our clothing today is made using synthetic fibers — the polyesters, fleeces and nylons of the world. A recent study estimated about 64,000 pounds of microfibers enter our water systems daily in the U.S. alone.

Fleece is one of many synthetic fibers to contain microfibers that don't break down in the ocean.

These materials don’t break down in ocean water and are instead ingested by animals who live there — from tiny zooplankton all the way up to massive, filter-feeding blue whales. Microfibers fill the bellies of fish, and, while the plastic remains in their guts, the toxins that microfibers contain can migrate into fishes’ flesh, consumed in turn by humans. Researchers found that about 25 percent of individual fish and 67 percent of all species intended for human consumption contained plastic debris, the majority being microfibers.

While we still don’t know the exact effects ingesting these tiny particles are having on us, the magnitude of the microfiber problem calls for immediate attention. From innovative laundry traps to calls for change within the expansive clothing industry, some very smart folks are working to tackle the issue.

The surest bet, however, remains using fewer plastic items in your day-to-day life. Try to avoid single-use bottles, straws and foods that come heavily packaged. Fish, and your tummy, will thank you for it.

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