I Tried the Cora Ball

The bright laundry accessory offered to protect marine life from my clothing’s microfibres. But would it work?

Three cora balls—blue plastic balls with ring-shaped protrusions that mimic coral that capture microplastics in the laundry.
Photo courtesy Cora Ball

The structure of the Cora Ball was inspired by the anatomy of coral.

There’s a good chance something you’re wearing right now will shed microfibres the next time you wash it. Microfibres are tiny threads made from synthetic fabrics such as polyester and nylon that are 100 times finer than a strand of human hair. They’re shed by fleece joggers and cozy sweaters, but also jeans and socks. A 2016 study estimated that 700,000 microfibres could be released in the wastewater from one laundry cycle alone.

The problem with microfibres, as with microplastics, is they’re a major source of aquatic and food chain pollution. Microfibres are sometimes mistaken for food by small marine animals and — due to their inability to biodegrade — build up in their digestive tracts. Larger fish that eat these smaller animals also absorb microplastics into their tissues, which humans then consume. Another study from 2016 found 83% of tamuatá fish taken from Brazil’s Pajeú River contained microplastics and specifically, microfibres.

Enter the Cora Ball and its creator, Rachael Miller. Made of 100% recycled and recyclable plastic, the ball goes in the wash with your clothes, and is designed to capture some of the microfibres shed during the laundering process.

Miller first started thinking about microfibres’ impact on marine environments in 2013, while running the Rozalia Project, the Vermont-based non-profit she co-founded that works to reduce marine debris through education, clean-up, research, and innovation.

“At that point, it was little known,” she says. “There really weren’t very many papers [studying the impacts]… It’s one of those problems that just screamed at us.” Soon after, Miller and her team began developing a concept for reducing microfibre shedding from laundry. Several versions later, the Cora Ball Kickstarter launched in 2017. With 8,635 backers, they blew past their initial goal of US$10,000 and raised $353,461.

You would have to stand at your washing machine and clean a simple mesh filter three or four times every single load.

While several microfibre filters are available to install where the laundry water drains out of washing machines, the Cora Ball takes a different approach. Miller illustrates why by describing how inefficient an inexpensive filter would be. “The problem is that without making something very complicated and extensive, [a filter is] just a piece of mesh,” Miller says. “You would literally have to stand at your washing machine and clean it three or four times every single load… so that your washing machine doesn’t back up.”

Miller and her team began looking to nature for a design that would attract and hold on to microfibres, while allowing water to flow continuously around and through it. The answer came to her when she looked into the ocean: coral. The structural anatomy of coral was the inspiration for Cora Ball. A study from the University of Toronto concluded it can capture 26% of microfibres shed in a single laundry cycle.

That study also examined the Lint LUV-R filtration system, which removed 87% of microfibres from the wash water. However, it’s more expensive, requires special installation, and needs to be cleaned out every 10–15 loads of laundry. So there’s a trade-off between effectiveness and convenience.

What’s the deal with 26%?

When I received my Cora Ball, I was so excited to throw it into my next wash and watch the fibres collect. In actuality, I only saw a few bright strands caught in the interior arms, and there didn’t seem to be more even after more washes. I was disappointed and frustrated.

Looking for Cora Ball reviews online, I stumbled across the fact it catches 26% of microfibres released in a load of laundry. That seemed woefully inadequate, so I decided to mention it when interviewing Miller.

She knew it was coming, and beat me to the question. She looks at it several ways. First: “It’s 25% of a really big problem. So it’s better than nothing. Doing nothing means 25% more of this stuff ends up in our public waterways and available for ingestion by creatures at all levels of the marine food web.”

Doing nothing means 25% more of this stuff ends up in our public waterways and available for ingestion by creatures at all levels of the marine food web.

In addition, she says they would have gone to market if Cora Ball only collected 10% of microfibres in a given load of laundry. “We feel that strongly about the need to make an impact, while we are waiting for more satisfying solutions to come out,” she says. The Cora Ball is meant to be part of a web of solutions, not the only solution.

My Cora Ball isn’t overflowing with lint, even after 10 washes, but there are tiny tangles of brightly coloured fibres deep within the structure. Speaking with Miller is reassuring; it’s easy to think that at only 26% efficacy, a company might be trying to pull one over on consumers. It’s clear that she cares deeply about microfibre pollution, though, and the safety of our oceans and waterways. Plus, Cora Ball donates all profits back to the Rozalia Project, which continues its work to reduce marine debris.

You might be wondering: if one ball can remove 26% of microfibers, will two balls double that volume? Miller explains, “We did find that additional Cora Balls do catch more fibre, but since they could line up in the wash, adding a second or third does not necessarily mean catching double or triple the microfibre.” She does, however, recommend using more in larger machines.

Other ways to shed fewer microfibres

The simplest way to reduce the number of microfibres shed in your laundry is by washing clothes less frequently. When you do laundry, Miller says, pack your washing machine full: “Do a full load because that reduces the friction between garments.” Front-loading washing machines cause less shedding as well.

Another option, for people without much synthetic clothing, is the Guppyfriend, a mesh bag that reduces the amount of microfibres entering the laundry water by 80–90%. I personally didn’t choose this option because my family owns a lot of cotton-polyester-blend clothing. It would be inconvenient and water-and-energy-intensive to wash our clothes one small bag-full at a time. Either that, or I’d need to buy a whole school of Guppyfriends.

When we spoke, Miller shared the Cora Ball team’s philosophy: “the phrase we use is, ‘lots of littles make a big.’” After several years of existential-dread-causing environmental reporting, this way of thinking eases my soul with every load of washing.

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