Fleecing the ocean

How laundering your fleece pullover impacts marine life

Created date

September 29th, 2017
A fleece jacket with microfibers.

A fleece jacket with microfibers.

One of the biggest fashion trends of the past decade is the “athleisure” movement. High-tech performance fabrics originally created for athletes and outdoor adventurers are now the garments of choice for just about everyone. 

In fact, 60% of all the clothing in the world is made from fabrics like polyester, rayon, acrylic, spandex, and nylon. These fabrics are easy to care for, comfortable, and stylish. They don’t stain, fade, or shrink, and neither the washing machine nor the dryer pose any threat to garments made from them.

However, a growing body of evidence suggests the garments themselves pose a threat to both the water supply and marine life.


At issue are the microfibers used to create today’s high-tech fabrics. Microfibers are threads as small as 3 microns or about half as large as a red blood cell. Each time a fleece jacket is machine washed, it sheds up to 250,000 microfibers, or about 2 grams worth. For comparison, a paperclip weighs about 1.5 grams. 

Consider how many fleece jackets and other synthetic garments get washed daily. New York City alone could generate over 6.8 billion microfibers in a single day. Those fibers are flowing directly into the New York harbor. 

Municipal waste water systems can filter out 65%-92% of microfibers, but that still leaves billions of microfibers floating out to sea. One estimate says there are 1.4 million trillion microfibers in the ocean, and a 2011 study found that microfibers account for 85% of manmade debris found on shorelines worldwide. 

Recycled plastics

When fleece was first introduced, you may have heard manufacturers tout the fact that the fabric was made from recycled plastic soda bottles. Fleece was marketed to consumers as a “sustainable” product and people believed that wearing fleece was good for the environment. 

It wasn’t until much later experts discovered that fleece and other synthetic fabrics were not environmentally friendly. Rather, these fabrics created an entirely new and, some would say, more severe environmental threat. 

While any plastic in the world’s water supply is harmful, microfibers present a unique problem. The microscopic size of plastic microfibers means they are ingested by all kinds of marine life—from plankton to oysters to whales. 

When sea life consumes microfibers, they consume less food, which can create an unhealthy situation. Furthermore, microfibers travel through the food chain. They may initially pass through the gills of a crustacean, but when a larger fish consumes that crustacean, the microfibers are consumed as well.   

Numerous studies have found microfibers in seafood intended for human consumption. A 2015 study found that one in three shellfish and one in four finfish for sale at a California market contained microfibers. In essence, we are eating our fleece jackets. 

Research findings

There are no easy or obvious solutions to this problem. Patagonia, a company that sells performance garments made from microfibers, has launched a campaign to study the problem and come up with ways to reduce the number of microfibers in the ocean. 

The company commissioned a study by the Bren School of Environmental Science and Management at the University of California, Santa Barbara. Conducted by graduate students, the study’s findings shed some light on the extent of the problem. 

While it may seem self-serving, the study found that higher-quality fleece (such as that sold by Patagonia) sheds fewer microfibers than low-quality generic brand fleece.

Researchers also found that older jackets shed more than newer ones, and jackets laundered in top-loading washers shed more than five times as much as jackets laundered in front-loaders.   


Given how ubiquitous synthetic fabrics are, it’s unrealistic to consider regulating or banning their production. 

Some have proposed improving municipal water filtration techniques. Another viable answer is to create better filters for washing machines. Just as clothes dryers have lint traps, washing machines could catch the fibers before they go down the drain. This is a realistic goal given that there are only about thirty washing machine manufacturers worldwide. 

Until such filters are available, consumers can help by doing less laundry. Not only will this reduce the number of microfibers released into the environment, it will also help extend the lifespan of your garments.

A recent study presented to the World Economic Council suggested that “in 2050 there will be more plastic than fish in the sea.” The study specifies that plastic packaging is the primary culprit, but clearly, plastic microfibers play a part too. Perhaps the most effective way to help curb this problem is to spread the word and support campaigns focused on it.

For more information, visit storyofstuff.org.