Humanity dumps 8 million tons of plastic into the oceans each year, according to a study published early this year in Science. That’s a mind-blowingly large figure, but it still doesn’t account for the untold billions of tiny plastic fibers from synthetic apparel that leave your washing machine and enter rivers, lakes, and oceans through wastewater treatment plants.
These fibers, as well as tiny bits of degraded trash and microbeads from personal care products, have generated a long list of questions and concerns among environmental scientists. In a new study in Nature, Chelsea Rochman, a marine ecotoxicologist from the University of California, Davis, addressed one of the chief concerns: Are those fibers and other microplastics getting into our food system? The answer: Yes.
To reach this conclusion, Rochman and her colleagues purchased and dissected fish and bivalves from markets near Half Moon Bay, California, and compared their contents to those of fish and bivalves purchased from a market in Makassar, Indonesia. In both locations, more than half of the species and roughly a third of the individual fish and shellfish contained foreign objects—most of which were microplastics—that the fish and shellfish filtered from the water or mistook for food. But while none of the debris collected from the Indonesian samples were fibers, the researchers concluded that the majority of debris collected from fish and shellfish caught along the California coast were fibers from textiles. (The study did not distinguish between cotton and synthetic fibers, the latter of which are so prevalent in outdoor performance wear.)
The researchers concluded that the majority of debris collected from fish and shellfish caught along the California coast were fibers from textiles.
“We were shocked” that none of the fish or shellfish from Indonesia contained fibers, says Rochman. She was not surprised, however, that the majority of debris in samples from California were fibers, since wastewater effluent from communities up and down the coast ends up in coastal waters and carries with it tiny fibers that evade filtration systems. The area in Indonesia from which the researchers purchased fish and shellfish, on the other hand, lacks that kind of wastewater treatment infrastructure, she says.
“Plus,” she adds, “don’t forget that washing machines are a luxury we take for granted.” People in undeveloped parts of Indonesia likely hand-wash their clothes outside.
Environmental scientists first raised concerns about these microfibers following a microplastics study published by British ecologist Anthony Browne in 2011. Browne found a preponderance of tiny polyester and acrylic fibers in beach sediment near wastewater treatment plants. More recently, researchers analyzed wastewater treatment effluent headed into the Great Lakes and found 85 percent of the microplastics it contained were fibers.
The results of Rochman’s study further incriminate apparel as a source of ocean pollution. Yet researchers still don’t know whether humans are at risk from ingesting microfibers, many of which scientists suspect are plastic. And if we are, to what degree? (It’s also worth noting that shellfish and small fish eaten whole, such as sardines, are the main ways humans will ingest the plastic debris, since in larger fish it settles in organs that are removed before consumption.) Past studies have shown that microplastics do absorb toxins such as DDT and PCB from waterways, so when we eat fish that contain fibers, there’s at least the potential for chemical harm. Studies have also shown that microplastics harm lugworms and small organisms and that they can accumulate in fish’s guts and tissues, potentially weakening immune or endocrine systems.
Even though more fibers were found in California’s fish, Rochman makes clear that Indonesian consumers are still facing a more vexing public health problem. “We found more plastic, overall, in Indonesia, and seafood is their main protein source, whereas it’s not for people in U.S.,” she explains.
Studies showing high quantities of synthetic microfibers in wastewater effluent and the unanswered questions around what harm they are doing to the ecosystem and public health has spurred the outdoor apparel industry to look inward. In our August issue, we broke news that Patagonia has launched a project with the Bren School of Environmental Science and Management at the University of California, Santa Barbara to identify which synthetic materials in its supply chain shed fibers. Adam Fetcher*, communications director at Patagonia, says research is still ongoing, but he’s confident the company will have findings to share by spring.
The Outdoor Industry Association (OIA) convened an industry task force dedicated to microfibers and ocean plastics and is working with its members, including Patagonia, and environmental groups such as Adventurers and Scientists for Conservation, to “better understand our impact and leverage points as an industry,” says Nikki Hodgson, corporate responsibility coordinator for the OIA.
In Europe, the European Commission funded research by the Italian National Research Council’s Institute of Polymers, Composites, and Biomaterials, which is also midstream. So far, says project lead Maurizio Avella, the project has surveyed 830 European households about the fabrics they wear and performed some baseline tests on a range of fabric types. The survey showed that about a quarter of all respondents’ apparel items are fully synthetic, with cotton-synthetic blends comprising 15 percent, and items made completely or mostly of natural fibers accounting for the remainder. Yet most respondents said they wash all of their clothes using cycles designed for cotton, which exerts more centrifugal force than is actually needed to clean synthetic fabrics. Plus, the research has found that powder-based, high-pH detergents, oxidizers, and washing in hard, high-temperature water all contribute to high fiber loss from the apparel being laundered.
One potential solution would be to capture the tiny fibers before they go down the drain, but the appliance industry has yet to make any substantive steps toward researching the feasibility of integrating additional filters to washing machines to collect fibers (though some aftermarket retrofits, designed for keeping lint out of septic tanks, are available). Jill Notini, spokesperson for the Association of Home Appliance Manufacturers, says the group is convening a technical group to discuss the issue.
Meanwhile, citizen scientists are also trying to aid microfiber research. Last month, Adventurers and Scientists for Conservation launched a multiyear research project to analyze water samples in Montana’s Gallatin River watershed in an attempt to quantify the inflow of synthetic fibers and other plastics into the water system close to their source. Rochman plans to continue her analysis as well. “I’d love to collect fish from all over world and analyze the chemicals in them,” she says.
This article has been updated to reflect the correct spelling of Fetcher.