As environmental challenges go, microfiber pollution has come from practically out of nowhere. It was only a decade or so ago that scientists first suspected our clothing, increasingly made of synthetic materials like polyester and nylon, might be major contributors to the global plastic problem.
Today a growing body of science suggests the tiny strands that slough off clothes are everywhere and in everything. By one estimate, they account for as much as one-third of all microplastics released to the ocean. They’ve been found on Mount Everest and in the Mariana Trench, along with tap water, plankton, shrimp guts, and our poo.
Research has yet to establish just what this means for human and planetary health. But the emerging science has left some governments, particularly in the Global North, scrambling to respond. Their first target: the humble washing machine, which environmentalists say represents a major way microfiber pollution reaches the environment.
Late last month a California State Assembly committee held a hearing on Assembly Bill 1628, which would require new washing machines to include devices that trap particles down to 100 micrometers — roughly the width of human hair — by 2029. The Golden State isn’t alone here, or even first. France already approved such a requirement, effective 2025. Lawmakers in Oregon and Ontario, Canada have considered similar bills. The European Commission says it’ll do the same in 2025.
Environmental groups, earth scientists and some outdoor apparel companies cheer the policies as an important first response to a massive problem. But quietly, some sustainability experts feel perplexed by all the focus on washers. They doubt filters will achieve much, and say what’s really needed is a comprehensive shift in how we make, clean and dispose of clothes.
The wash is “only one shedding point in the lifecycle of the garment. To focus on that tiny, tiny moment of laundry is completely nuts,” said Richard Blackburn, a professor of sustainable materials at the University of Leeds. “It would be much better to focus on the whole life cycle of the garment, of which the manufacturing stage is much more significant in terms of loss than laundering, but all points should be considered.”
Today, some 60 percent of all textiles incorporate synthetic material. Anyone who’s worn yoga pants, workout gear or stretchy jeans knows the benefits: These materials add softness, wicking and flexibility. Under a microscope, though, they look a lot like plain old plastic. From the moment they’re made, synthetic clothes — like all clothes — release tiny shreds of themselves. Once liberated these fibers are no easier to retrieve than glitter tossed into the wind. But their size, shape, and tendency to absorb chemicals leaves scientists concerned about their impacts on habitats and the food chain.
Anja Brandon is an associate director for U.S. plastics policy at the Ocean Conservancy who has supported the California and Oregon bills. She concedes that filters won’t fix the problem, but believes they offer a way to get started. She also supports clothing innovations but said they could be years away. “I for one don’t want to wait until it’s a five-alarm fire,” she said.
Studies suggest a typical load of laundry can release thousands or even millions of fibers. Commercially available filters, like the PlanetCare, Lint LUV-R and Filtrol, strain the gray water through ultra-fine mesh before flushing it into the world. It’s the owner’s job, of course, to periodically empty that filter — ideally into a trash bag, which Brandon said will secure microfibers better than the status quo of letting them loose into nature.
Washing machine manufacturers in the U.S. and Europe have pushed back, saying the devices pose technical risks, like flooding and increased energy consumption, that must be addressed first. University experiments with these filters, including an oft-cited 2019 study by the University of Toronto and the Ocean Conservancy, haven’t found these issues, but it’s not a closed case yet: Last year a federal report on microfibers, led by the Environmental Protection Agency and National Oceanic and Atmospheric Administration, called for more research in this vein.
Manufacturers also argue that microfibers originate in a lot of places, but washers are a relatively modest one. As self-serving as that sounds, people who study the issue agree there’s a huge hole in the available science: While we know clothes shed microfibers throughout their lives, we know surprisingly little about when most of it happens.
Some evidence suggests that the friction of simply wearing clothes might release about as many microfibers as washing them. Then there are dryers, which some suspect are a major source of microfiber litter but have been barely studied, according to the federal report. There is also limited knowledge about how much microfiber pollution comes from the developing world, where most people wash by hand. (A recent study led by Hangzhou Dianzi University in Hangzhou, China pointed to this knowledge gap – and found that hand-washing two synthetic fabrics released on average 80 to 90 percent fewer microfiber pollution than machine-washing.)
To Blackburn, it’s obvious that most releases occur in textile mills, where it’s been known for centuries that spinning, weaving, dyeing and finishing fabric spritzes lots of fiber. “Where do you think it goes when we get it out of the factory?” he said. “It goes into the open air.”
He calls filter policies “totally reactionary,” arguing that they would at best shave a few percentage points off the total microfiber problem. But there is one area where Blackburn is in broad agreement with environmentalists: In the long run, tackling the issue will take a lot of new technology. No silver-bullet solution has appeared yet, but a slew of recent announcements reveals a vibrant scene of research and development attacking the problem from many angles.
Some best practices already are known within the industry. For example, more tightly woven clothes, and clothes made of long fibers rather than short ones, fray less. But for years, popular brands like Patagonia and REI have said what they really need is a way to experiment with many different materials and compare their shedding head to head. This has been tricky: Microfibers are, well, micro, and there’s no industry standard on how to measure them.
That might be changing. In separate announcements in February, Hohenstein, a company that develops international standards for textiles, and activewear brand Under Armour revealed new methods in this vein. Under Armour is targeting 75 percent “low-shed” fabrics in its products by 2030.
These approaches would at best reduce microfiber emissions, not eliminate them. So another field of research is what Blackburn calls “biocompatibility”: making microfibers less harmful to nature. California-based companyIntrinsic Advanced Materials sells a pre-treatment, added to fabrics during manufacturing, that it claims helps polyester and nylon biodegrade in seawater within years rather than decades. Blackburn’s own startup, Keracol, develops natural dyes, pulled from things like fruit waste, that break down more easily in nature than synthetic ones.
New ideas to dispose of clothes are also emerging, though some will cause arched eyebrows among environmentalists. This year U.S. chemical giant Eastman will start building a facility in Normandy, France that it claims “unzips” hard-to-recycle plastics, like polyester clothes, into molecular precursors that can be fashioned into new products like clothes and insulation. Critics charge that such “chemical recycling” techniques are not only of dubious benefit to the environment, they’re really just a smokescreen for fossil-fuel corporations trying to keep their product in demand.
Lest anyone forget about washing machines, there’s R&D going after them, too. In January Patagonia and appliance giant Samsung announced a model that they claim cuts micro plastic emissions up to 54%. It’s already rolled out in Europe and Korea. At around the same time, University of Toronto researchers published research on a coating that, they claim, makes nylon fabric more slippery in the wash, reducing friction and thus microfiber emissions by 90 percent after nine washes. In a press release the researchers tut-tutted governments for their focus on washing-machine filters, which they called a “Band-Aid” for the issue.
One continuous thread through all these efforts, of course, is that everyone is working with imperfect information. The emerging science on microfibers – and microplastics in general – suggests they’re a gritty fact of modern life, but doesn’t yet show the magnitude of their harm to humans and other species. For the moment environmentalists, policymakers and manufacturers aren’t just debating whether to put filters on washing machines, but whether we know enough to act. In 20 years, when scientists know a lot more, it’ll be easier to judge whether today’s policies represented proactive leadership on an emerging environmental problem — or a soggy Band-Aid.
Click the link to read the release on the Arizona State University website (Richard Harth):
In the arid regions of the American Southwest, an unseen world lies beneath our feet. Biocrusts, or biological soil crusts, are communities of living organisms. These industrious microbes include cyanobacteria, green algae, fungi, lichens and mosses, forming a thin layer on the surface of soils in arid and semiarid ecosystems.
Biocrusts play a crucial role in maintaining soil health and ecosystem sustainability, but they are currently under assault. Human activities including agriculture, urbanization and off-road vehicle use can lead to the degradation of biocrusts, having long-term consequences for these fragile environments. Climate change is also placing stress on biocrusts, which struggle to adapt to sunlight and searing heat in arid landscapes like the Sonoran Desert.
To help with this issue, Arizona State University researcher Ferran Garcia-Pichel and his students have proposed an innovative approach to restoring healthy biocrusts. The idea is to use new and existing solar energy farms as nurseries for generating fresh biocrust.
Safely shielded from the sun beneath arrays of solar panels, like beachgoers under an umbrella, the biocrusts are sheltered from excessive heat and can flourish and develop. Ultimately, the newly generated biocrusts can then be used to replenish arid lands where such soils have been damaged or destroyed.
Help for desert soil
In a proof-of-concept study, ASU researchers adapted a suburban solar farm in the lower Sonoran Desert as an experimental breeding ground for biocrust. During the three-year study, photovoltaic panels promoted biocrust formation, doubling biocrust biomass and tripling biocrust cover compared with open areas with similar soil characteristics.
When biocrusts were harvested, natural recovery was moderate, taking around six to eight years to fully recuperate without intervention. However, when harvested areas were reinoculated, the recovery was much faster, with biocrust cover reaching near-original levels within one year.
The researchers emphasize that the use of similar, but larger, solar farms could provide a low-cost, low-impact and high-capacity method to regenerate biocrusts and expand soil restoration approaches to regional scales. They have dubbed their pioneering approach “crustivoltaics.”
The study estimates that use of the three largest solar farms in Maricopa County, Arizona, as biocrust nurseries could empower a small-scale enterprise to rejuvenate all idle agricultural lands within the county, spanning more than 70,000 hectares, in under five years. Among many environmental benefits, this restoration effort has the potential to significantly decrease airborne dust presently impacting the Phoenix metropolitan region.
“This technology can be a game changer for arid soil restoration,” Garcia-Pichel said. “For the first time, reaching regional scales at our fingertips, and we could not be more excited. To boot, crustivoltaics represents a win-win approach for conservation of arid lands and for the energy industry alike.”
Garcia-Pichel is a Regents Professor in the School of Life Science and the founding director of the Biodesign Center for Fundamental and Applied Microbiomics. The center amalgamates researchers that study assemblages of microbes, or microbiomes, acting in unison in various settings, from humans to animals and plants, to oceans and deserts. Garcia-Pichel’s lab has specialized in the study and applications of desert soil microbiomes.
The group’s findings appear in the current issue of the journal Nature Sustainability, in a publication co-lead by graduate student Ana “Meches” Heredia-Velásquez, and former graduate student Ana Giraldo-Silva, now a professor at the Public University of Navarre in Spain. A separate briefing of this contribution appears concurrently in Nature.
Biocrusts are complex ecosystems researchers have only recently begun to explore. Among their many functions, they act to stabilize soil by binding soil particles together, minimizing the loss of topsoil caused by wind and water. They contribute to nutrient cycling by fixing atmospheric nitrogen, a process where nitrogen gas is converted into ammonia, making it available to plants. Cyanobacteria, which are present in biocrusts, are the primary organisms responsible for this process.
Photosynthetic activities within biocrusts play a role in carbon storage by fixing atmospheric carbon dioxide. This process can help mitigate some of the effects of climate change by removing CO2 from the atmosphere. Biocrusts also increase the soil’s water-retaining capacity, allowing more water to infiltrate the soil and reducing runoff. This helps to improve water availability for plants and other organisms in arid ecosystems.
Finally, biocrusts support a diverse community of microorganisms that contribute to overall ecosystem biodiversity and resilience.
Drylands, which make up approximately 41% of the Earth’s continental area, are experiencing severe degradation due to human activities and climate change. The communities of microorganisms on soil surfaces are vital to protect and fertilize these soils and are essential for dryland sustainability. However, current biocrust restoration methods involve high effort and low capacity, limiting their application to small areas. Existing methods have struggled to replenish more than a few hundred square meters of land.
The research suggests that solar farms serve as biocrust hotspots, as the elevated photovoltaic panels create a greenhouse-like microclimate promoting biocrust development. Although crustivoltaics is a slower and weather-dependent method compared to greenhouse-sized biocrust nurseries, it has many advantages. The technique requires fewer resources, minimal management and no upfront investment. Indeed, the use of crustivoltaics is 10,000 times more cost effective than current methods, according to the research findings.
The next steps will involve implementing crustivoltaics at regional scales through the cooperation of scientists, collaborative agencies, land users and managers. Use of the technique can provide incentives to solar farm operators, including reduced dust formation on solar panels and increased revenue from carbon credits.
The crustivoltaic approach has the potential to offer a dual-use solution for both solar power generation and biocrust restoration on a large scale while also providing socioeconomic benefits. This method could play a significant role in the restoration and sustainability of dryland ecosystems.