A microfiber solution inspired by coral reef

The Cora Ball, a microfiber catching laundry ball, on a stack of dish towels

We've always been in awe of Rachael Z. Miller, NatGeo Explorer and co-inventor of the Cora Ball. Ahead of World Oceans Day, we caught up with her to learn more about microfibers and the exciting projects she has in the works.

🔵 Hi Rachael, let's dive right in! Can you share a bit about your background? What prompted you to study microfibers in the environment?

Rachael Z. Miller: I am a water person through and through. I’ve spent my entire working life connecting people to the water either through wind- and human-powered sports (sailing and paddling) or conserving the places I love so much—rivers, lakes, and our one, big ocean—by working to understand them better in order to develop and deploy solutions to protect them.

We started the Rozalia Project, our nonprofit, with the goal to protect the ocean primarily by addressing the problem of marine debris. Back in 2010 when we launched our programming, and still today, we work on derelict fishing gear, consumer debris, and microplastics.

Rachael Z. Miller presenting at The Explorer's Club in NYC

When we learned that microfibers, in particular, make up the vast majority of the pieces of microplastics in our waterways, we made them a specific area of focus with the goals to contribute scientific knowledge, come up with a solution, and raise awareness through presentations and education programs to people of all ages. And we’ve been doing just that with great partners like Celsious!

🔵 Was there a finding, paper or moment in particular that motivated you to invent a microfiber solution?

It was in 2013, and though we had worked on microplastic pollution for a few years, we had only been looking at microplastics that were visible to the naked eye and collected from the water with a net.

I read an article in a popular science magazine about microfiber pollution that was recently discovered and linked to clothing and washing machines in particular, and it was one of those problems that didn’t just speak to me; it screamed at me. We started working on a solution around 2015 and launched the Cora Ball in late 2017.

🔵 How did you settle on the name "Cora Ball"?

Because it is inspired by coral! During the design process, we got a bit stuck. When that happened, we reframed the goal from “we need to catch microfiber” (which no one had done before) to “we need to catch small things from moving water.”

Shortly after we did that, we visited the Monterey Bay Aquarium, and as we walked by a coral exhibit, we realized that nature does it—coral stalks catch tiny plankton from moving water. Right then, we had our design inspiration, and the name followed.

Close up of the Cora Ball, a microfiber catching device

We called it "Cora Ball" instead of "Coral Ball" because we didn’t want people to think it was made of coral.

🔵 Speaking of, what is the Cora Ball made out of?

The Cora Ball is made out of a same-cyclable synthetic rubber with recycled content. The conditions in a washer are harsh so we found that the material needed to be durable. Our own requirements were that it was not just recyclable into anything but that we could make new Cora Balls out of old ones. And we can.

The original Cora Balls—now seven years old—remain fully intact with no signs of wear and tear! It is also important to note here that we designed the Cora Ball to be fixable. If any part breaks, we can replace just that one part.

Rachael Z. Miller with her invention, the Cora Ball.

🔵 What are some of the biggest misconceptions about microfibers?

One is that we are only referring to something related to microfiber cleaning cloths. That is not the case. All textiles are at risk of experiencing fiber fragmentation when microscopic bits of fiber break off the longer fibers used to make the garment, home textile, rope or the like, and those bits are the microfiber pollution we are working to prevent.

The second is that clothing made from natural fibers is exempt from concern. I am afraid that is not the case. So much of even our naturally-derived clothing, such as cotton, still poses a risk to the environment for multiple reasons. These include acting as a vector for dye setting and other chemicals related to the fashion industry to reach our public waterways.

Infographic showing the microfiber path from washing machines to ocean

Another risk is that the fibers themselves do not biodegrade quickly, and when ingested, they can still endanger small creatures. That is why we made the Cora Ball a solution that addresses the entire load of laundry rather than isolating the synthetics. We don’t want any man-made fibers getting into our lakes, rivers, and shared ocean.

🔵 Thank you for reminding us that natural fibers—and not just synthetic ones—have an impact on the environment. Let's pivot now. Can you share any updates re: the Rozalia Project and/or expeditions on the horizon?

We always have exciting projects and updates for Rozalia Project! This summer, our oceanographic research vessel, American Promise, and volunteers from around the world are working on remote islands in the Gulf of Maine, recording and removing tons (literally) of derelict fishing gear and consumer debris. This is part of an exciting coalition of organizations throughout New England and funded by NOAA.

I am about to head for the sub-Arctic to be the Visiting Scientist onboard the National Geographic Endurance sampling the air and water for microplastic and anthropogenic (manmade) microfiber in Norway, the Shetland Islands, the Faroe Islands, and Iceland.

I am excited about this for so many reasons including that of those places, I’ve only been to Norway and it will be so interesting to compare to the results from our expedition to the high Arctic on the same ship last year.

You can check out those results, as well as results from an expedition in Hawai'i, here. While you’re there, check out more about Rozalia Project and our programs!

🔵 Is there anything else you'd like to share before jetting off to Norway?

Before signing off, I want to say a big shout out to everyone at Celsious. Taking care of our clothing is such an important part of taking care of our planet on the whole. We appreciate everything you all do to help people do just that, and supporting organizations like ours along the way. An ocean-sized thank you to your whole team!

An ocean-sized thank you from us to you, Rachael!

Shop the Cora Ball here.

Interview and photo of Rachael Z. Miller at The Explorer's Club by Mutia Adisoma
All other photos and infographic courtesy of Cora Ball

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