- A handful of startups in the U.S., Europe and Asia are helping the seafood industry fight plastic pollution by creating equipment made from fungi.
- Efforts are currently focused on replacing plastic foam, a polluting component of numerous elements of the seafood supply chain, with mycelium, the root-like structure of fungi.
- A company in Maine makes mycelium-based buoys for the aquaculture industry, for example.
- Elsewhere, projects are seeking to create biodegradable mycelium-based coolers for transporting fish.
Mycologists believe the solution to some of our biggest pollution issues is under our feet. Humble fungi are now being used as meat alternatives, eco-friendly leather and to help break down waste such as plastics. While a new industry, the market for mycelium, the root-like structure of fungi, is forecast to reach $6.5 billion by 2032. Now nascent startups are using it to help curb pollution from the seafood industry.
The solutions created by these startups are timely. South Korea has banned marine buoys made with Styrofoam from 2025, and MPs in Canada are calling for a similar ban. The European Union has stated that in 2025, manufacturers will be responsible for the end life of fishing gear. And the United Nations is expected to release a global treaty to curb plastic pollution by the end of 2024, adding more pressure.
Plastic foam can break down into microplastics, which marine wildlife commonly mistake for food to the detriment of their health. Research shows seafood consumption is one way humans can be exposed to microplastics. Fishing gear accounts for a major portion of the plastic polluting the ocean: 10% globally, but up to 100% in certain places, according to a recent overview study.
In 2022, mycologist Sue Van Hook launched MycoBuoys in Maine, U.S., a startup aiming to reduce the sea’s plastic burden by turning mushrooms into buoys for the aquaculture industry. Van Hook discovered that mycelia could float while at New York-state based Ecovative, one of the biggest innovators in mushroom-based materials. “[Mycelia] have these uniquely evolved proteins to repel water for a certain amount of time,” Van Hook says.
To grow the buoys, Van Hook and her team place wood-rotting fungi and hemp into a buoy-shaped mold. The mycelia grow by feeding on the hemp, taking five days to fill the mold. The mycelium buoy is then removed and dried. Van Hook experimented with numerous substrates, including hops, rice, soybean hulls and corn stocks; ultimately hemp shone out.
Eleven shellfish and seaweed aquafarms in the northeastern U.S. are now trialing MycoBuoys to hold cages (called “traps”) and lines. The buoys last for five months, the length of an oyster or kelp season. Van Hook says the company, poised to scale a line of cylindrical buoys, will be able to match the average $7 to $14 cost of the plastic foam-filled polyethylene floats the industry now relies on.


The plastic and foam buoys last from 3-10 years. But they can pollute the ocean when they start to degrade. And while foam can be recycled, many jurisdictions do not have the ability to do so. When the MycoBuoys start to disintegrate at their end of life, the farmer can use them as fertilizer on land. The dried fungi and plant material won’t contaminate the ocean, Van Hook says. She is now seeking a coating that will help lengthen the buoys’ lifespan.
“We have to design purposively for circular economies. We can’t keep [creating] these massive waste streams,” she says.
Marine biologist turned oyster farmer Abigail Barrows was one of the first people to test the MycoBuoys. As a microplastics researcher, when Barrows bought the Deer Isle Oyster Company in Maine in 2015, she was determined to make it plastic-free.
“We have created a very plastic world in a very short amount of time, and the problem is that plastics are made with hazardous materials,” Barrows says. “And those hazardous materials have known human health effects and animal effects.”
Barrows, who has been using mycelium buoys for four seasons, is now designing her own. Her aim is to make them more durable so they can be used internationally. “We have to have something that can handle massive swings in salinity, lots of different temperatures, lots of different biofoul and organisms,” Barrows says.
At least one other company has been working on mycelium buoys: A company in South Korea filed a patent in 2022 for mycelium buoys grown on waste beer hops.
On the other side of the United States, the University of Alaska Anchorage has joined with the Center for Alaskan Coastal Studies and Alaska Native communities to help remove plastic foam from further along the seafood supply chain. Local fishing companies are now piloting the project’s mycelium coolers as a replacement for foamed plastic coolers used to transport fish. The two-year-long project, which launched in September 2022 with a $184,000 grant from the National Oceanic and Atmospheric Administration, is now building mycelium coolers in a space donated by the Coal Point Seafood Co. in Homer, Alaska. The company’s owner, Nancy Hillstrand, said her team had wrestled for some time with finding environmentally friendly alternatives to plastic foam. Heavier eco-friendly packaging from materials like cardboard could add to their shipping costs or fuel usage as it would be delivered to the fishing company from elsewhere in the U.S. by truck.
The Center for Alaskan Coastal Studies discovered that Styrofoam was the biggest contributor to the debris collected at the community marine debris clean-ups it runs each fall. “[Plastic foam] is used for so much, especially in Coastal Alaska in the form of fish boxes and dock floats,” says Henry Reiske, who helps coordinate the mycelium program for the center. “When this polystyrene escapes, it is a major environmental issue.”

Reiske says the compostable coolers are an important step in curbing plastic pollution. “For shipping fish, there [aren’t many] options on the market. The choice is Styrofoam. The mycelium coolers allow us to have an option for people who want to ship seafood in a box that is not harmful to the environment,” he says.
While it is still a pilot scheme, Reiske says he believes as it progresses the material could replace a huge amount of plastic foam being used in the state.
In the Netherlands, mycelium packaging company GROWN bio has been approached by fishing-sector companies looking for sustainable options for transporting fish. A Norwegian company has already trialed its mycelium coolers to transport salmon, and GROWN bio is now in talks with a big company in Hamburg, Germany, that ships fish to Asia.
Packaging entrepreneur Jan Berbee launched GROWN bio in 2018, in search of a more sustainable alternative to plastic foam and single-use plastics.
GROWN bio’s large mycelium coolers, priced at 10 euros (about $11) each, have 95% of the insulation capabilities of the lighter Styrofoam. However, the company is testing the wetland plant cattail (Typha latifolia) as a feedstock, as it is three times lighter than the hemp it currently uses. “This means there’s less weight, more air, more insulation capabilities,” in the resulting material, Berbee says.

The company is now moving from demo to commercial and making cost its focus. It has already brought the price down from 20 to just two to three times that of plastic foam coolers, according to Berbee.
That’s a common challenge for mycelium startups, according to Susanne Gløersen, the founder of The Future is Fungi Award that celebrates mycelium research and innovation “When you deal with biology, scaling up can be a challenge [as you move] from lab production to massive scale,” she says. “It is also important to bring costs down, to be on par with petro-based alternatives.”
Gløersen is bullish on potential marine uses for mycelium. “The industry is still in its infancy, but I am convinced that we will see numerous applications in the years to come,” she says.
Banner image: Nets, ropes, buoys and other fishing equipment bursting out of decaying bags in Dungeness, Kent, U.K.; photographed in 2016. Image by Maureen Barlin via Flickr (CC BY-NC-ND 2.0).
Mycoremediation brings the fungi to waste disposal and ecosystem restoration
Citations:
Smith, M., Love, D. C., Rochman, C. M., & Neff, R. A. (2018). Microplastics in seafood and the implications for human health. Current Environmental Health Reports, 5(3), 375-386. doi:10.1007/s40572-018-0206-z
Apete, L., Martin, O. V., & Iacovidou, E. (2024). Fishing plastic waste: Knowns and known unknowns. Marine Pollution Bulletin, 205, 116530. doi:10.1016/j.marpolbul.2024.116530
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