Skip to main content

Why Microfibers are a Real Problem

Don’t look now. They’re everywhere.

By now it’s clear that microfibers from synthetic clothing are some of the most pernicious forms of plastic pollution. Less than 0.2 inches long, these tiny strands are in the water we drink, the fish we eat and the air we breathe. Their size, or rather lack thereof, makes it easy for them to spread across vast distances. Every time someone takes a jog in a sweat-wicking tank top or throws a fleece jacket into the wash, thousands of strands of polyester, nylon or acrylic pull loose from their surface, ready to be whisked off to parts unknown. One University of California, Santa Barbara study estimates that 4,000 metric tons—the equivalent of 13.3 quadrillion fibers—inundated California’s natural environment in 2019.

But while clothing is the “second-most discarded item of plastic after food packaging,” according to Lisa Erdle, manager of research and innovation at the 5 Gyres Institute, a California-based research nonprofit, there remain gaps in our knowledge because research is “still relatively young on this issue in general.” Most of the science around microfibers has involved the consumer end of the equation. Shedding during the production of textiles, on the other hand, has remained largely a “black box,” she said.

This past June, on World Oceans Day, scientists from the Nature Conservancy and Bain & Co. published what they say is the first estimate of microfiber emissions from textile manufacturing and materials processing. The results weren’t comforting. Roughly 0.12 million metric tons of synthetic fibers are released at this pre-consumer stage into the environment every year, a similar order of magnitude to the post-consumer one. In more measurable terms, for every 500 shirts manufactured, one vanishes as microfiber pollution.

“So the scale of this is really significant,” said Tom Dempsey, oceans program director at the Nature Conservancy in California. “It’s part of this problem to really merit and urgently require action.” Textile manufacturers, he said, aren’t usually aware of this issue and rarely test for microfibers in their waste streams, yet the dyeing, printing, finishing and prewashing stages are all abrasive “wet” processes that can cause yarns to shed at high rates and foul waterways if left untreated. Proper containment, too, is a concern. Microfibers can get stuck at wastewater treatment plants, where they’re incorporated into sewage sludge that is used to fertilize cropland. From there, they can contaminate crops or be buffeted by wind and rain into the nearest water body.

Related Stories

The situation is bound to get worse. Synthetic fibers comprise over two-thirds (69 percent) of all materials used in textiles today, according to petrochemical analytics company Tecnon OrbiChem. By 2030, they will make up more than 75 percent. With little to no intervention, the study predicts that pre-consumer emissions could increase by 54 percent by 2030.

The good news is there is already an array of off-the-shelf solutions that can stem the flow of microfibers at this juncture; suppliers just need to be made aware of them. “In many conservation challenges that we’ve worked on, we’re thinking about new technologies and innovations,” Dempsey said. “In this case, the solutions exist. We know how to filter water.” Even better, advanced filtration techniques can help textile manufacturers save water, making them at least cost effective if not a smart investment that can improve their bottom lines.

The fashion industry has dawdled long enough, in Dempsey’s opinion. For years, brands and retailers have struggled to develop standardized and internationally aligned test methods for evaluating microfiber release. The pieces have only started to click in place. The Microfibre Consortium (TMC), a multistakeholder initiative whose roster includes Adidas, Gap Inc., Patagonia, and Zara owner Inditex, was the first to offer a version to its members in late 2019 before opening it to the public. The American Association of Textile Chemists and Colorists made its test method available for sale in August.

3D rendering of a microscopic close up view of a simple woven textile. Adobe Stock

“It’s important to have information and understanding as you try to tackle any problem and certainly a problem that’s as complicated and sweeping as is,” Dempsey said. “And yet gathering information is not enough. I would [also] argue that we have enough information in hand right now to take meaningful ambitious action to try to stem the flow of microfibers.”

While TMC wasn’t involved in the Nature Conservancy study, the group is poised to release a roadmap-slash-commitment that will form an “aligned agenda” for the fashion sector with “clear accountable outputs” for signatories to take coordinated action, according to Sophie Mather, its executive director. One of the areas of focus is industrial microfiber emissions. “What is great about the roadmap is we’re making sure that we’ve got industry commitment behind it, and people are held accountable to keep the targets that are outlined,” she said.

Still, there are a lot of complexities with the issue, Mather said. Dealing with microfiber emissions isn’t as easy as shutting off some imaginary spigot. Creating clothing that sheds less, or doesn’t shed at all, is even more challenging. Everything from the twist of the yarn to the type of machinery being used can affect the integrity of the fiber. “No two textiles are exactly the same,” she said. “There are so many different variables as to why [shedding] is happening, and to understand all of those and make changes without affecting the performance of the material is really quite difficult.”

All of which is to say, partnership—among brands, textile manufacturers, researchers and third-party labs—is key. “We need one agenda, one vision and one set of targets that everybody can work toward,” Mather said. “I believe that we can get there, but it’s too big a challenge for one organization to do on its own. It has to be done in a collaborative way.”

To help move things along, the ZDHC (Zero Discharge of Hazardous Chemicals) Foundation, a multi-stakeholder initiative whose goal is reducing the garment industry’s use of toxic substances, joined TMC in June as a research partner. An update of its guidelines, set to launch in November, will include microfibers, along with testing methods and limit values. Ahead of that, ZDHC and TMC plan to publish a white paper to further the sector’s understanding of the subject.

“ZDHC, in collaboration with TMC, is conducting research to understand the sizes and numbers of microfibers formed during textile wet processing and intends to introduce stringent limit values into the wastewater guidelines, together with advice on how those stringent limits can be met,” said Phil Patterson, chair of the ZDHC MRSL Council. “This will be the first time any organization takes definitive, large-scale action to mitigate releases into the environment.”

“This will be the first time any organization takes definitive, large-scale action to mitigate releases into the environment.” – Phil Patterson, ZDHC MRSL Council

Patterson said that ZDHC isn’t interested in “debating the relative harms of sub-sections of the industry” or villanizing polyester as the “main culprit.” In his opinion, all fibers from textiles and industrial sources should be managed.

Indeed, despite the obvious target posed by synthetic textiles, natural fibers aren’t off the hook, either, said Krystle Moody Wood, founder and principal at Materevolve, a technical-textile consulting firm from California. When scientists at the University of Cape Town in South Africa analyzed 2,000 microfibers gathered from oceans around the world in 2019, for instance, they found that only 8 percent were plastic fibers. The rest were plant- or animal-based materials such as cotton, wool, hemp and linen.

“Anything that has been processed, dyed, treated, didn’t come from a cotton boll or off a sheep’s back has the potential to be an environmental pollutant and contribute to this issue,” she said. “There are things like PFAS, the water-repellent class of chemicals that we’re still using to treat natural and synthetic fibers even though they’re regulated in other parts of the world. So there are a lot of impacts, whether [the fiber is] natural or synthetic, because it’s really about persistent toxicity.”

Diana Rosenberg, senior manager of product sustainability at Gap Inc., one of the brands that contributed to the Nature Conservancy study, agreed companies should be approaching the question of microfibers from a holistic point of view. “All fibers shed in the normal wear and tear of life,” she said. “We can’t keep trying to chase the one material that we should be blaming for this problem. Each fabric needs to have a way of examining how to bring that load down and eventually eliminate it.”

Just as important, Rosenberg said, is moving from “learning into action.” “The next step is really to start figuring out how do we actually implement the test standards that have been developed,” she said. “How do we contribute toward the development of the next level of understanding in terms of what is it that contributes to higher levels of microfiber shed? What types of fibers tend to fragment at a higher rate? What’s happening in knits? What’s happening in wovens?”

When testing a piece of fabric for colorfastness and abrasion resistance, for instance, Gap might start checking for shed rates. Or it might ask its textile mills to start measuring microfibers in effluent. Having those elements integrated into ZDHC standards would be invaluable, Rosenberg said. “We are collecting so much information there and we already have samples happening,” she added. “We don’t have to re-create a system and increase the collection burden at facilities.”

Patagonia is one brand that has been paying attention to the growing microfiber emergency since it made itself known. The outdoor-wear purveyor funded the pioneering 2016 study that found that a single fleece jacket can slough up to 250,000 microfibers during a single wash. Since then, Patagonia has kept microfibers among its “top five” priority issues, according to Elissa Foster, its head of product environmental impact.

Foster said she thinks the company is making progress, but that the path hasn’t been as straightforward as it thought it would be. “It’s been very hard to identify those key switches or changes that you can make to the twist of the yarn or the way the fabric is knit or woven to reduce shedding,” she said. “We’ve had some hypotheses on [different] fabric constructions, but then when we did the testing we found exceptions with everything.”

Amid the uncertainty, Patagonia is going to keep plugging away. Having a standardized testing method will certainly spur efforts, Foster said. So will work by Nature Conservancy, TMC, ZDHC and others to identify leakage hot spots that brands and suppliers can tackle together. “There are a lot more points in the fabric-creation life cycle that we aren’t necessarily directly involved in,” she added. “That seems to be where the holes in the knowledge are now.”

Foster said it’s unlikely we’ll arrive at a solution that will halt microfiber generation entirely, neither will synthetic fabrics fade into obscurity any time soon. The crux of the matter is manufacturing textiles that shed less and capturing any wayward bits before they escape into the environment. Getting it right will have to involve everyone, including those in the halls of government.

“There are a lot of places along the life cycle of a fiber getting into the environment that we all need to just acknowledge,” Foster said. “Brands are absolutely a piece of the solution, suppliers have a role, the washing machine industry has a role, there’s a place for aftermarket filters. There’s the wastewater treatment space. And then policy can come in to support those different areas.”

Sustainability NOW 2021

This article is part of Sourcing Journal’s comprehensive Sustainability Report 2021. Click here to download the report.