This Is Not Compostable—But Fungi Don’t Care

Plastics will outlive us all.

That’s not a metaphor—it’s a material fact. Since the 1950s, humanity has produced over 8.3 billion metric tons of plastic. (Geyer et al. 2017, https://doi.org/10.1126/sciadv.1700782) The vast majority of it—nearly 80%—has ended up in landfills or scattered across natural ecosystems, never to fully degrade. Less than 9% has ever been successfully recycled. Despite decades of messaging from the plastics industry about recyclability and environmental responsibility, the truth is plain: we have been lied to.

And while “biodegradable plastics” are often touted as an eco-friendly alternative, most require very specific industrial composting conditions to actually break down. In landfills and oceans, they behave little differently than conventional plastics, often fragmenting into microplastics rather than degrading completely. These microplastics, in turn, now contaminate everything from deep-sea fish to human bloodstreams.

But buried beneath this bleak landscape of petroleum polymers lies an unlikely solution—one that’s been here long before plastic ever existed. Fungi.

The Mycelial Solution

Fungi are nature’s original recyclers. Unlike plants or animals, fungi absorb their nutrients externally, secreting powerful extracellular enzymes that chemically digest material in their surroundings before drawing in the liberated compounds. Over billions of years, fungi have evolved to break down lignin in wood, chitin in insects, keratin in hooves and feathers—and now, it appears, they’re beginning to tackle plastics too.

I read a few research articles and a National Geogrpahic article promising how fungi could save the world and get rid of plastics. "Unbelievable," I thought. And so I set forth to disprove this research - the basis of what science really is: disproving theories. (Khan et al. 2017, https://doi.org/10.1016/j.envpol.2017.03.012)

During my time as a student in community college, I conducted a year-long research project on the potential for fungi to degrade petroleum-based plastics. I used landfill soil, wood pulp, newspaper, coffee grounds, and layered in both PET (polyethylene terephthalate) HDPE (high-density polyethylene), and LDPE (low-density polyethylene) plastic strips. The experimental conditions were outdoor and semi-controlled—intentionally closer to real-world waste environments than pristine laboratory setups.

I inoculated the substrate piles with multiple fungal species, including seven genotypes of Pleurotus djamor and three of Aspergillus tubingensis. After about three months, I started to see a change. The plastic strips began to degrade—becoming brittle, dull, and riddled with microfissures under the microscope. These weren’t just visual changes. The fungi were physically altering the plastic, digesting it, breaking it down.

This wasn’t a miracle—it was mycelium doing what it’s evolved to do. And it confirmed what I had read in early research articles: fungi can digest plastic. The only catch? They need to be trained.

Enzymes on the Front Line

Plastic degradation by fungi hinges on their enzymatic output—particularly extracellular enzymes like cutinases, lipases, laccases, and various peroxidases. These enzymes attack the long, stable polymer chains that make plastics resistant to decomposition. Cutinases, for example, can cleave ester bonds in polyesters like PBSA, while lipases act similarly on synthetic fats and oils. Peroxidases, such as lignin peroxidase and manganese peroxidase, initiate radical-mediated attacks that break down highly stable molecules like polyethylene.

The secret lies in gene regulation. Fungi naturally produce these enzymes when faced with complex substrates. But when exposed to plastic as a primary carbon source, they upregulate the genes that code for these enzymes, adapting over generations to digest the new material. This generational adaptation—backed by mechanisms like epigenetic imprinting—allows fungi to become more efficient at degrading plastic over time.

And while Pleurotus djamor and Aspergillus tubingensis are standouts, they are far from alone. A 2022 paper from the National Library of Medicine (Ekanayaka et al. 2022, https://doi.org/10.3390/jof8080772) highlights over 50 species of Ascomycetes and Basidiomycetes that exhibit plastic-degrading potential, including Trichoderma hamatum, Fusarium sp., Acremonium kiliense, Paecilomyces lilacinus, Aspergillus flavus, and Aspergillus fumigatus, among others. Soil-borne fungi, in particular, show the most promise—likely due to their naturally competitive, adaptive environments.

The Extremophilic Advantage

Landfills are inhospitable places. Temperatures fluctuate wildly. Oxygen levels vary from fully aerobic to deeply anaerobic. Some areas are as dry as deserts, while others are waterlogged and acidic. It's a chaotic ecosystem—one that very few organisms can survive, let alone thrive in.

Fungi, however, are extremophiles.

They’ve been found growing in the acidic thermal pools of Yellowstone, thriving on volcanic seabeds, and surviving inside nuclear reactors. Some chytrid species inhabit oceans. Others transform into dormant forms—sclerotia, spores, or resistant hyphal mats—to outlast harsh conditions. When the environment becomes favorable again, they resume growth as if nothing happened.

This adaptability is encoded not just in their DNA, but in their ability to epigenetically respond to their surroundings. When presented with plastic, fungi can gradually shift their behavior, metabolic pathways, and enzyme production to suit this strange new food source. They imprint their environment into their genome, adapting in ways that industrial composters and bacteria simply cannot.

This is why fungi are uniquely positioned to tackle the waste buried in landfills—environments too unpredictable and harsh for most biological degradation strategies.

Training Fungi for the Task

Companies like Hiro Technologies in Austin, Texas, are already leveraging this potential. While their methods are proprietary, it’s likely they’re using a process of selective adaptation: growing fungi on substrates with increasing concentrations of plastic over successive generations. Starting with 1% plastic and 99% organic matter, then gradually increasing the ratio until the fungi learn to treat the plastic as food.

Each fungal strain is likely matched to a specific type of plastic—PET, LDPE, polystyrene, or polyurethane. By training these strains to thrive on a particular substrate, they’re creating a bioengineered army of decomposers tailored to the waste materials we most desperately need to break down.

One of their pilot projects involves inoculating disposable diapers—plastic-heavy, nutrient-rich waste items that typically go straight to landfills. With trained fungal strains embedded in the diaper lining, these products become vectors for waste breakdown from the moment they’re discarded.

It’s a brilliant idea. But we need more than brilliance—we need scale.

From Petri Dish to Policy

The biggest barrier to deploying fungal solutions at landfill scale is not science—it’s economics.

Convincing waste management companies to invest millions into fungal inoculation systems, monitoring technologies, and infrastructure isn’t easy. Waste is still seen as a sunk cost, not a resource worth investing in. Worse yet, incineration remains one of the most common methods for plastic disposal—releasing toxic chemicals and CO₂ instead of actually solving the problem.

To scale, we need a shift in thinking. Fungal solutions can be integrated into our existing waste systems. Bioreactors at sorting facilities could use sterilized food waste to cultivate plastic-degrading fungi. Inoculated substrates could then be sprayed onto trash as it enters landfills. Legacy waste piles could be treated with aerial spore dispersal—using drones or helicopters to cover large areas quickly.

This isn’t science fiction. It’s logistics. And it can be done.

Toward a Regenerative Future

What fungi offer is not just a way to degrade plastics—it’s an invitation to rethink how we interact with waste, ecology, and industry itself.

In our current model, waste is treated as an unfortunate byproduct. It’s buried in lined pits, incinerated, or exported to countries with fewer regulations. Even well-intentioned recycling efforts are mostly a shell game—just 9% of plastics ever get recycled, and much of what we "recycle" ends up in landfills or the ocean. This isn’t a sustainable system. It’s a global sleight of hand.

Fungi teach us to see differently. For fungi, waste is not the end of a product’s life—it’s the beginning of a biological process. Where we see toxic debris, fungi see an opportunity for transformation. They don’t neutralize waste—they reintegrate it into living ecosystems.

This is the foundation of regenerative design: systems that heal, replenish, and restore. Imagine a future where landfills are no longer dead zones but thriving biological engines. Where the same fungal networks that once evolved to digest wood and chitin are now used to break down polyethylene and polyurethane. Where every bit of trash that enters a landfill is inoculated with spores designed to digest what we’ve been told is indigestible.

This isn’t speculative fiction—it’s feasible science waiting for infrastructure.

Here's how we get there:

Municipal waste facilities could integrate fungal bioreactors to cultivate plastic-degrading strains on-site using sterilized food waste. These mycelial cultures could then be sprayed on trash at the point of entry, starting the breakdown process before waste even hits the landfill. Drones could be deployed to spread spores across legacy mounds—sites we’ve written off as lost to time. With coordinated action, we could transform thousands of acres of inert plastic fields into living systems of decay, reclamation, and renewal.

But fungal remediation needs more than Petri dishes and pilot projects.

It needs policy. It needs capital. It needs urgency.

A Call to Policymakers:

Your cities and countries are spending billions on landfill management, recycling programs that don’t work, and PR campaigns to cover the inefficacy of our current systems. Instead, fund the future. Redirect a fraction of these budgets toward scalable fungal remediation programs. Invest in public-private partnerships that incentivize waste processing facilities to trial fungal solutions. Mandate inoculation protocols for specific waste streams. Support local startups and university labs pioneering this work.

Fungi can be a part of climate strategy, environmental justice, and regenerative infrastructure—all at once.

A Call to Venture Capitalists and Climate Tech Funds:

The plastic problem isn’t going away—and current "solutions" are flimsy at best. This is your chance to back a biological platform technology with truly planetary potential. Funding the industrial-scale production of fungal spawn, bioreactor facilities, genetic optimization, and UAV-based deployment systems could yield exponential returns—not just financially, but ecologically.

You’re looking for scalable, sustainable, IP-generating solutions to planetary problems. This is one of them.

We need funds not just for research, but for implementation. For site-level trials, for infrastructure buildouts, for licensing technologies and making them accessible to waste facilities from Austin to Accra. We need a fungal moonshot—not for the sake of novelty, but survival.

Final Thoughts: Don’t Bury the Solution

We’ve spent decades clinging to the myth that plastics are under control—that recycling works, that landfills are harmless, that biodegradable packaging will save us. But the truth is more uncomfortable: we are drowning in chemical waste that no system we’ve built can manage.

Yet nature has always had an answer.

Fungi evolved to decompose the toughest materials on Earth. They don’t need industrial facilities or perfect conditions—they need opportunity. And when given that chance, they rise to the task with quiet, relentless efficiency.

This isn’t speculation. We’ve seen it in the lab, in the soil, in pilot programs around the world. Fungi can digest what we were told would last forever. But we need to meet them halfway—with infrastructure, funding, and vision.

Landfills don’t have to be dead ends. They can be living systems. Bioreactors can replace incinerators, upcycling stored energy into a brand new resource. Policy can empower regeneration instead of prolonging pollution. And capital can fuel mycelial solutions that scale globally.

The question is no longer if fungi can solve the plastic crisis. The question is whether we’ll give them the chance.

Let’s stop burying the solution—and start growing it.