My happy place is that chaotic zone of salt and spray where the beach meets the sea, a place of coming and going, flux and exchange. I love to dig my toes into the suctioning sand and feel the swirl of a receding wave. Though often my feet find sharp things in the soft sand—not just gravel and pebbles but also, increasingly and overwhelmingly, plastic. I try to collect the shards, the bits of aquas, whites, and teals, but soon I give up, angry and defeated. There is too much. So much of it is too tiny to hold or even see.
These tiny pieces are called microplastics, and they measure less than 5 millimeters (PDF) in length (or, smaller than the width of a #2 pencil). Microplastics are ubiquitous now—at the Jersey Shore of my childhood, in Hawaii and Japan (where my families live), and in California, my new home. There is almost nowhere on earth that plastics haven’t been found, not even in the depths of the ocean. In October 2020, scientists in Australia published a study estimating that 9.25 to 15.86 million tons of microplastics can be found on the ocean floor. Or, as The New York Times reported: “18 to 24 shopping bags full of small plastic fragments for every foot of coastline on every continent except Antarctica.”
The human world runs on plastic, and microplastics come from a variety of sources: larger pieces of plastic (like bottles) that break apart into smaller and smaller fragments, car tires, plastic beads (including those in skin-care products), and synthetic fibers. We now know that clothing, bedding, and other textiles shed microplastics in fiber form and (along with tire degradation and road runoff) are major contributors to global plastic pollution. These microfibers, which are stripped and carried off by friction and turbulence in the washing machine, enter our wastewater, eventually ending up in the environment.
The study of microfiber pollution is relatively new. Just 10 years ago, a group of scientists published a breakthrough study of shorelines on six continents; it pointed to laundry as a significant source of plastic pollution in the world’s oceans. Specifically, the study found plastic microfibers—tiny polyester and acrylic threads that matched those in textiles. Today scientists estimate that textiles produce 35% of the microplastic pollution in the world’s oceans (in the form of synthetic microfibers), which would make textiles the largest known source of marine microplastic pollution. That’s about 2.2 million tons of microfibers entering the ocean every year.
“We have a plastic pollution crisis,” said Alexis Jackson, a marine biologist and scientist with the California chapter of the Nature Conservancy, an environmental advocacy organization. “The face of that crisis looks a lot different [than we thought]. It’s not just plastic bags and soda bottles. It’s all of these microplastics that you can’t see with the naked eye that are pervasive in the environment.”
To address the microfiber pollution problem, a few products have cropped up that claim to keep microplastics out of wastewater when you wash your clothes. The Guppyfriend laundry bag and the Cora Ball are two of the better-known options. Girlfriend Collective—which makes one of our leggings picks from recycled polyester sourced partially from recycled PET (polyethylene terephthalate) bottles—now sells a microplastics filter that you attach to your washing machine (albeit with some difficulty, according to reviews). Though these products won’t singlehandedly solve the massive global problem of microplastic pollution, they may raise awareness and help reduce wastewater pollution on an individual scale.
I ordered a few of these filters to view them firsthand, and I’ve used a couple of them in recent weeks. For now, we can’t give authoritative advice about which of these options is the “best.” There are many factors affecting the performance of these filters, such as washing-machine type, the size and makeup of a laundry load, the detergent, and the wash cycle. Also, there isn’t a lot of competition for microfiber filters, especially for ones available in the United States. To make things more complicated, there’s not yet a standardized, peer-reviewed metric or certification for comparing the claims of these filters, as there is for, say, water filters. Although a handful of scientific studies have compared the effectiveness of some of the filters out there, the results vary based on methodology and variables like washing-machine model, fabric type, and detergent. And as two experts separately told me, it’s important to remember that “there’s no silver bullet” solution. Nonetheless, there are things you can do to reduce microplastics pollution when you wash your clothes.
I set about trying to understand the problem that devices like the Guppyfriend and the Cora Ball are designed to solve, as well as what to keep in mind while weighing potential solutions.
Where do plastic microfibers come from?
The yarns in our clothing are made up of filaments that are twisted together. During washing, with the effects of water, friction and abrasion, and detergents, those filaments shed. Different types of fabric shed more than others. A tightly woven fabric with tightly twisted yarn (one that feels flat and smooth) sheds less than a loosely woven fabric with loosely twisted yarn (one that feels fluffy or fuzzy). “Everything from the quality of the raw material input to the quality of the processing machinery to the skill and expertise of the mill is going to affect the quality of a fabric and therefore its shedding,” said Stephanie Karba, an environmental researcher at the outdoor-clothing maker Patagonia. “We’ve also found that partnering with a very good mill and working with a high-quality yarn can lead to a stronger, more durable fabric that sheds less.”
Patagonia, which has staked its tent on sustainability claims, has reason to get ahead of this: Studies show that synthetic fleece can be one of the biggest shedders. To further reduce microfiber shedding, Patagonia recommends spot-cleaning its fleece most of the time.
One potential solution to the microplastics problem is to buy clothing made with natural fibers—rather than polyester and nylon—whenever possible. But “the switch to natural clothing, which is one of the most promoted solutions [to the microfiber pollution problem] that I’ve seen, is not really a solution because it’s not that simple,” said Sam Athey, an environmental chemist and PhD candidate at the University of Toronto Rochman Lab. She explained that even textiles labeled “100% natural” can contain up to 30% chemical additive by weight, often applied for stain resistance, water repellency, fire retardancy, and antimicrobial properties. Unless a garment says it is completely untreated, “because of issues with transparency in the textile industry, you don’t always know what chemicals your clothing contains.”
“The concern is that not only are those chemicals toxic in themselves, and that these fibers may act as transport vectors to carry the chemicals to the environment, but these chemicals can also affect how long these fibers are in the environment, so they prolong their persistence. One of the big problems with plastics is that they last so long in the environment. Well, if you change these natural fibers to make them more persistent in the environment, they also become a problem,” Athey said.
For this reason, rather than just switching to “natural” fibers and calling it a day, it makes sense to find ways to reduce microfiber shedding in laundry. And laundry isn’t the only culprit. We now know that our clothing sheds microfibers pretty much constantly, just by being worn. Although scientists first found synthetic microfibers in the ocean (which pulled the focus to the impact of laundry), more recent research now shows that our clothes shed almost as many microfibers into the air.
But for many individuals, it’s easier and more practical to capture microfiber pollution by changing laundry practices than by, say, going nude. So we’re focusing on what happens in the wash.
Where do the fibers in our clothes end up?
Wastewater treatment is effective at catching microfibers that come out in the wash; some can capture as much as 98% of them. But studies show that due to the huge volume of water that a wastewater treatment plant processes daily, a significant amount—65 million microplastics per center per day, according to one study—still makes its way into the environment. Once there, the microplastics move up the marine food chain or are taken up into crops through soil. Since microplastics do not biodegrade and are impossible to recover once released into habitats, the problem is only growing.
Even those microfibers that water treatment does capture may end up back in the environment, as happens in California, according to a forthcoming study of microfiber pollution by the Nature Conservancy and UC Santa Barbara. In that state, biosolids captured during water treatment may be spread on agricultural land as fertilizer. Alexis Jackson, a marine biologist and collaborator on the study, said that through this research, household “filtration technology actually proved to be more effective in the near term.” This is because no matter how effective a treatment center is, “if they’re taking those byproducts and putting them on land, you become more effective at putting that pollutant [back] into the environment.”
No matter the pathway, plastic microfibers from clothes have shown up in food, as well as in bottled water, tap water, beer, and sea salt (PDF). An American Chemical Society study published in 2019 reported that “our estimates of American consumption of microplastics are likely drastic underestimates.” Scientists are still studying the health impacts of ingesting plastic—including on the immune system and in childhood development. But we do know that we’re all being exposed to plastic constantly. (Because no standards for microplastics currently exist from the American National Standards Institute, ANSI, or NSF International—two bodies that oversee product claim requirements—none of our water filter picks are certified for microplastic filtration.)
The microfibers that our clothing shed may have significant consequences for ecosystems in water and on land, as well as directly on our health—the extent of which scientists are just beginning to understand. We have a major environmental problem, and it’s linked to our clothes—how we design them, how we make them, how often we buy them, and how we care for them. “The global production of stretchy synthetic textiles is expected to triple by 2050,” said Jackson. “So this is a problem that’s not going away.”
Do laundry filters help?
There are two kinds of filters that you can buy to address microfiber shedding in laundry. The first is a filter that you add to your washing machine’s water outflow, to catch fibers before they enter municipal wastewater. The second is an accessory you throw in the wash along with your clothes, such as laundry balls that capture microfibers or laundry bags made from woven monofilaments with a small pore size.
Do they help? The short answer is maybe. A handful of studies (one of which was supported by clothing brand Eileen Fisher) demonstrate that both in-drum and external microfiber filters reduce microfiber pollution in the wastewater system to varying extents. Both types require periodic cleaning to remove the stuff that builds up, and those fibers must be thrown in the trash—not washed down the sink—to actually divert plastics from wastewater. (Of course, that plastic will then end up in landfills and, over time, may leach chemicals back into the environment. There is no perfect solution.)
At the moment, there are no standardized methods or metrics for comparing these devices, and this is why we can’t recommend a pick or definitively point to one we trust most. “Quantifying microfiber release from clothing is complex,” said Imogen Napper, a research fellow at the University of Plymouth who co-authored a study in 2020 comparing the effectiveness of six microfiber filtration devices. “It can be potentially impacted by temperature, use of detergent or conditioner, type of washing machine, type of garments washed and their polymer type.” Scientific findings may also differ from company numbers, which is not necessarily cause for distrust; this is to be expected if there is no consistent testing methodology.
That said, not all devices are equal. They differ in ease of use, cost per life cycle, transparency, and evidence-based backing. What works best is ultimately the device that has at least one third-party test behind it and that meets your lifestyle and needs.
External microfiber filters: pricier up front, require installation
A microfiber filter that you attach to the outside of your washing machine may be an option. It will require more effort than just using a laundry bag or similar accessory. But other than attaching the filter and emptying it every two to 10 loads (depending on the filter and what you wash), you won’t need to adjust how you do laundry (as you might when using laundry bags or balls). Most filters are bulky, however, so you need to make sure you have enough room for the filter you choose (and, if you rent, have approval from your landlord). For example, Filtrol ($140 at the time of writing) is 15 inches tall and 9 inches wide, and it should be installed with 1 to 2 feet of clearance above the filter (to access it for cleaning). Another option, LUV-R ($180 at the time of writing) is similar in size, at about 13 inches tall and 10 inches wide, and it requires 16 to 18 inches of top clearance.
The Girlfriend Collective Microfiber Filter is cheaper ($45 at the time of writing). But the price does not include the eight additional parts (PDF) you have to source on your own. Depending on your personality, you may find sourcing these components (like a hose, which the Filtrol and the LUV-R kits include) to be an “unbelievable hassle,” as one recent reviewer observed on Girlfriend Collective’s site. We have not yet tried the filter we purchased, but one Wirecutter staffer is planning to install it, and we will update this piece with the results.
When used correctly, the LUV-R has been shown in tests to reduce microfibers. But it’s difficult to definitively say how effective this device is, given the lack of standardized methods. A 2020 study by scientists with the International Marine Litter Research Unit, at the University of Plymouth, found that the LUV-R reduced microfibers in wastewater by 29%, plus or minus 15%. But another study published the same year found that the LUV-R reduced shedding by 74%. (Both studies sought to mimic household laundry practices.) Neither study included the Filtrol in testing, so it cannot be compared. Of six devices tested in the study, XFiltra (expected to become available soon) was found to be the most effective filter (a 78% reduction). Girlfriend Collective does not share its filter’s effectiveness. But according to its website, the company is working with a third party to provide a capture rate.
Laundry bags and balls: portable and ready to go out of the box (with some limitations)
If you have limited space around your washing machine or setup sounds like too much of a DIY project, or you rent, do laundry at a laundromat, or are on a tighter budget, you may prefer a microfiber bag (which you fill with your garments and toss in the machine) or a laundry ball (which goes into the drum with your load).
Laundry bags and laundry balls cost less than external filters, but they don’t necessarily save you money in the long run. Expect to spend between $20 to $40 per item. The Guppyfriend laundry bag (approximately 29 by 20 inches) is about $35, and the Cora Ball is $38 (all prices at the time of writing). However, you may need more than one of these devices, depending on your typical laundry load size. Alexander Nolte, co-founder of Guppyfriend, told me that for large loads, the company recommends using two bags per wash cycle, to avoid overstuffing the bag. For most effective cleaning, each bag should be filled to two-thirds its volume (what I estimated to be about 15 adult T-shirts). There is no device-constrained limit to the amount of clothing per load you can wash with the Cora Ball, but the company does suggest adding up to two more balls if you notice many fibers being caught in a single wash cycle.
If you are considering getting a laundry bag, there are a few microfiber-filtering bags available, the most common being the Guppyfriend. It’s made with woven monofilament, a single polyamide filament, similar to fishing line, that does not disintegrate into fibers the way yarn does. The material gives it a smooth, almost slippery, windbreaker-like feel. It’s sold directly through the website, as well as through outdoor retailers like Patagonia and REI. As do other wash-cycle laundry bags (even those that don’t claim to reduce microplastic pollution), the Guppyfriend protects delicates in the wash. Probably because it has been available the longest, since 2017, the Guppyfriend seems to also be the most robustly tested and researched bag of any of its competitors. The 2020 University of Plymouth study found that the Guppyfriend reduced microfibers by 54%. Yet, as with any device, the actual reduction will differ based on the variables of your machine, the type and quantity of laundry, the detergent, and the cycle, among other factors.
The Cora Ball is the only laundry ball I found that is commercially available and marketed toward the microplastics problem. It is a grapefruit-sized, pine-cone-like plastic orb whose spines are capped with soft, doughnut-shaped plastic discs to protect your clothes from snagging. In the University of Plymouth study, of the six devices tested, the Cora Ball was the third most effective, reducing microfibers by about 31%, versus 54% for the Guppyfriend. Since neither device is perfect but both have been shown in testing to reduce microfiber shedding into wastewater, it may be more important to consider what you wash—and how.
The company does not recommend using the Cora Ball with lace fabrics or loose knits because it can snag on threads and damage delicate clothing, and the company states that items with straps, like bras, may wind their way around the ball. I haven’t yet tested the Cora Ball, but just holding it, I observed it has enough toothy components that I’d be nervous to use it for delicates. (I have personally gravitated toward using the Guppyfriend over the Cora Ball, because I use it with athletic wear and other delicates. I have not attempted to use both together since neither product was designed to be used in tandem, and it is unclear whether the agitation from the Cora Ball could affect the performance of a laundry bag.)
Other things to consider
Just as with the external microfiber filters, you’ll need to clean the laundry bags or the Cora Ball, but how frequently you do this will vary. Over time, larger strands like hair and pet fur, as well as tiny fibers, will start to accumulate in the spines of the Cora Ball or the seams of the bag. At some point, that build-up has to be removed and disposed of in the trash. Some reviewers have found cleaning these devices to be annoying. For those with limited dexterity or mobility, cleaning around the seams or plastic spines may be extra-frustrating or impossible.
In independent testing by the German Textile Research Institute, Guppyfriend withstood 50 washes (a sixth of what Energy Star estimates the average US household washes in a year) without degrading. The company claims that the bag will “continue to be effective for years to come” when washed as directed, with cold water. I have used Guppyfriend more than 100 times at this point, and see no signs of wear. Cora Ball does not suggest replacing its device after a set number of uses, although the company does offer free spindle replacement for the first year.
All of the devices available—both external filters and in-drum bags and balls—are either mostly or 100% plastic in some form. And, in the United States at least, because these plastics are classified as “other,” they will be difficult, if not impossible, to recycle. (Guppyfriend recommends recycling the bag in Germany, where recycling practices are different. Cora Ball claims that its plastic is 100% recyclable, but US recycling practices make this more complicated.) I didn’t find any studies comparing the amount of plastic these devices contribute to landfill versus what they’re able to divert from wastewater throughout their life cycles. As of now, neither Cora Ball nor Guppyfriend offers a product reclamation program.
What can you do without a filter?
Everyone I spoke with for this piece stressed that the plastic microfiber problem cannot be solved by individuals alone, and that it will require changes across scales and industries. Some of those changes are being discussed at the state or federal level. California’s legislature, for example, is considering a bill that would identify and eventually require effective microfiber filtration in laundry facilities. In February 2020, France became the first country to require that, by 2025, new washing machines will be able to filter microplastics. And in March 2021 Australia announced, in its National Plastics Plan (PDF), a phase-in of such filters in commercial and residential washers by July 2030. Even so, Jackson said, the impact of individual practices “should not be underestimated.”
The experts I spoke with suggested a few tactics. Some of them are intuitive, like doing laundry less often and reducing the volume of water you use in proportion to fabric (because studies suggest that more water causes more microfiber shedding). This means you should wash full loads when possible and—surprisingly—avoid delicates settings, since delicates cycles use more water but less agitation. Experts also suggest using front-loading washing machines, since they are found to cause less shedding than top-loading models, and to line-dry your clothes when possible. Guppyfriend advises washing on cold—advice that is echoed elsewhere. Sam Athey washes with cold water but said the effect of warm water temps on microfiber shedding doesn’t have sufficient scientific evidence. “I know there’s not good scientific consensus to say that cold water washes reduce microfiber loss during laundry, but at the same time, I know that cold water washes are better for fluid energy consumption and that low volume washes are good for water consumption. So other environmental impacts factor into my practices as well.”
Even though all of this may be overwhelming, Athey suggested taking a pragmatic, multi-pronged approach to doing laundry. “One solution is not going to work for everyone. … It’s good to know what solutions are out there and consider adopting more than one.”
So, what can you do to reduce microfiber pollution?
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2. Melanie Bergmann, et al., White and wonderful? Microplastics prevail in snow from the Alps to the Arctic, Science Advances, August 14, 2019
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6. Imogen E. Napper and Richard C. Thompson, Release of synthetic microplastic plastic fibres from domestic washing machines: Effects of fabric type and washing conditions (subscription required), Marine Pollution Bulletin, September 26, 2016
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