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Do Fungi Break Down Plastic? Could Mushrooms Be the Antidote for Our Toxic Plastic Problem?

Updated: Mar 15

In 1907, Leo Baekland developed Bakelite, the first fully synthetic plastic, kicking off a manufacturing revolution that permanently altered the course of history – pushing us in a dangerous direction. But thanks to recent research, amateur mycologists may soon be helping to correct that course.


The Scourge of Plastic


Used for everything from jewelry to dishware, Bakelite was special because it was moldable and durable, and unlike earlier plastics derived from naturally occurring cellulose, Bakelite was not biodegradable. While it wasn’t immediately apparent what a huge problem this would become, Bakelite’s success spurred the development of the plastics industry, which hasn’t stopped growing since.


At this point the amount of plastic we produce in a given year rivals the combined mass of every human on Earth, and much of that incredible bulk is likely to stick around long after we’re gone – regardless of its “recyclable” status. Now, faced with the ecological impact of the massive Pacific garbage patch, and the discovery of harmful microplastics in everything from rainwater to human placental tissue, it’s clear we need to change course.



Plastic removed from the ocean


The spread of plastic pollutants to every corner of the earth and into every organ and system of the human body will undoubtedly prove to be a pressing ecological issue in the coming decades – if not far longer. But while there are efforts underway to reduce our dependence on plastics through a mix of public policy and material innovations, we are left to contend with the waste we’ve already created. Namely, several billion tons of synthetic plastics that already litter our planet’s surface. So far there are no straightforward solutions, but bioremediation may be our best hope.


Using Nature to Save Nature


The concept of bioremediation – using specialized life-forms to clear pollution from the environment – has been a proven strategy since at least 1972, at the site of a ruptured pipeline outside Philadelphia. In that case, cleanup was focused on keeping gasoline-metabolizing bacteria healthy and happy. While still a relatively new field of research, bioremediation has since proved among the most powerful tools for restoring nature where humanity’s impact threatens its destruction.


Of course, different pollutants call for different approaches to bioremediation. Following the nuclear disaster at Chernobyl, for example, sunflowers were used to remove heavy metals from the soil. In the case of plastic pollution, a number of options for bioremediation have been explored. Mealworms and certain types of bacteria have demonstrated some potential, but the use of fungi – AKA mycoremediation – may represent the greatest promise.


Do Fungi Break Down Plastic?


Yes, recent research suggests that certain fungi show promise in degrading plastics.


Plastic in a compost bin
Can you compost plastic?

Ckgurney, CC BY-SA 3.0 <https://creativecommons.org/licenses/by-sa/3.0>, via Wikimedia Commons


Common sense would suggest that tackling plastic pollution with biological processes is hopeless on its face. After all, the whole problem with standard plastics is that they aren’t biodegradable, right? Which is just another way of saying that biology can’t hurt them – nothing  has figured out how to “eat” them.


Without a “predator” to consume them, plastics are left to be degraded by natural forces like ultraviolet rays from the sun – a much slower process that can take centuries. But surprisingly, the same may once have been true of a material that Leo Baekland didn’t have a hand in. One that predates human industry by hundreds of millions of years – wood.


While the specifics of the timeline are debated, there is no question that if fungi had not evolved powerful enzymes capable of digesting lignin – the natural polymer that lends wood its rigidity and resilience – forest ecosystems could not function as they do today. Nothing else on Earth comes close to fungi in this respect.


Lignin is a long-chain polymer full of strong chemical bonds. Way too tough for most organisms to do much with it. The only reason the earth’s surface isn’t covered in piles of fallen tree trunks (or the ashes of globe-spanning forest fires) is that fungi found a way to eat the inedible.


The group of fungi known as white rot can sever those strong chemical bonds, quickly reducing even the toughest of hardwoods to nutrients that can cycle back into the ecosystem. Perhaps the same could one day be done with the synthetic polymers of common plastics.


That’s the hope that researchers around the world have begun putting to the test, with new discoveries being made all the time. Among the latest, a 2023 study out of Sri Lanka set out to assess 22 species of wood-decaying fungi for their ability to break down LDPE – a type of plastic found in various applications from milk cartons to six-pack rings.


Every species tested showed some promise – with Phlebiopsis flavidoalba outperforming the rest. But what’s even more encouraging is that when the fungi were deprived of wood, the plastic degraded faster…



Phlebiopsis flavidoalba is a fungus that breaks down plastic

Phlebiopsis flavidoalba, Django Grootmyers, @heelsplitter


In other words, it appears that there are already fungi capable of adapting to plastic as their primary food source. Granted, plastics are still not their first choice, but the good news for mushroom hobbyists and amateur mycologists is that there might be an opportunity to help change that.


Crowdsourced Evolution?


Thanks to a new offering from the mushroom-growing supply company North Spore, anyone with a little know-how and $75.00 can potentially contribute to the next big stage in fungal evolution – not to mention a huge leap forward for bioremediation.


That’s the cost of North Spore’s Plastic Degrading Plate Culture of Pestalotiopsis microspora.

It’s been known for a while that P. microspora, AKA leaf spot, is able to break down certain plastics. A 2011 study in Applied and Environmental Microbiology showed it to be effective at degrading polyurethane (PUR) – found in insulating foams, footwear and countless other applications. While it’s probably (definitely) not the best idea to start dumping your old shoes into the compost with a culture plate of P. microspora, there’s nothing to stop you from putting a chunk of that old shoe – or any other PUR plastic – into a moist, cozy tupperware with that fungal culture, and let natural selection take over.


While sterile laboratory settings are ideal for formal research, evolution is not a formal process. The rapid rate of fungal reproduction certainly helps, but the more hobbyists who are out there toying with P. microspora – placing it under different stresses with different types of polyurethane, and letting it do its thing – the more likely some random mutation will pop up that leads to a breakthrough in the field.


A new enzyme that kicks ass and chews plastic – and it’s all out of ass (sidenote: did you know most chewing gum is made of plastic? gross). One hobbyist’s fluke could end up being the key to jumpstart the long process of cleaning up civilization’s mess.


Correcting the Geological Record


The history of the Earth is recorded in its geology – in layers of sedimentary rock stacked on top of each other. The deeper you go, the further the fossils and atmospheric markers in those layers drift away from the environment we recognize today. But the gradual changes of previous eras – a billion years of species and kingdoms branching off, competing for control of niches, or even going suddenly extinct – aren’t reflected in the present day. Everything is changing much more quickly.


Our layer – the strip of rock that tells the story of human civilization – is still forming. But unless we change our ways, it will be a story of recklessness and waste embodied in all the little bits of plastic preserved in the stone. Our forgotten trash replacing the abundance of lifeforms we’ve driven extinct.


Mycoremediation could be humanity’s opportunity to tell a better story – using fungi to begin removing that toxic trash from our fragile ecosystems, and from our legacy.


If you have an interest in Mycoremediation, be sure to take a look at Organic Mushroom Farming and Mycoremediation, a book by Milkwood, a company based out of Australia known for its expertise in organic farming and mushroom cultivation education.


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