Fungi: The Invisible Web That Cleans Pollution and Builds the Future

They are among the most remarkable organisms on earth, yet mostly invisible. Their web expands and connects the dots of our entire global ecosystems and are essential for the cycle of life: Fungi. "The fungi kingdom had a decisive role in the evolution of life, not just in the previous time, but even in current times." They degrade almost everything, sponge up some of the most hazardous pollutants and can even create entirely new materials. They are strange and magical in ways that are often overlooked. This raises a compelling question: could fungi potentially help to clean up the mess on our planet and become the building blocks of our future?

The Hidden Kingdom: What are Fungi and Mycelium?

To understand their potential, we must first explore their hidden existence. The mushrooms you put in your risotto, see on your rotten veggies, or find in the forest are equivalent to the tip of an iceberg. They belong to their own biological realm, distinct from both animals and plants. Their secret life evolved over a billion years ago, and during that evolution, fungi became the trailblazers of life as we know it. Millions of years ago, they mined nutrients from rocks and provided them to plants, helping them grow and produce the oxygen that makes our lives today possible. Within a couple of hundred million years, these microscopic life forms developed into real giants. On the Arab peninsula, archaeologists found a fossil they initially thought was a tree; it turned out it was actually an 8-meter-high mushroom that grew 500 million years ago. However, the mushrooms we see on the surface are only the fruit of something much more vast. The real magic happens beneath the surface where the mycelium—the rootlike web of the fungi—mostly grows. It is the largest known organism on the planet. The mycelium of the “Humongous Fungus” in Oregon spreads through an area of 9km^2 and is estimated to be up to 8650 years old.

The Planet’s Great Recyclers: Degrading Lignin and Keeping Soils Healthy

Fungi are among the few organisms on the planet that can significantly break down lignin, a component in wood cells, but also present in fruits and any kind of tree or plant that decays after dying. "So if in the environment that would accumulate, that would be detrimental, then the nutrients would not be available to the plants again or to any other life form in the soil. So it's absolutely essential that there is someone who can degrade that fraction." Erika Kothe, a mycologist at the University of Jena in Germany, is investigating the symbiosis between plants and fungi. Fungi are essential to keep our soils healthy, and scientists are just beginning to explore their amazing abilities.

Mycoremediation: Using Fungi to Tackle Global Pollution

"So if fungi can help in the decomposition of a living thing, which is more complex than any organic compound, then this same set of organisms can also help in breaking down any organic pollutants in the environment." Udeme Dickson, who lectures in analytical environmental chemistry at the University of Reading in the UK, is looking into how fungi could potentially help clear land of oil pollution. "We have a lot of studies which [have] proved that toxic substances have been degraded by fungi."

Cleaning Oil Spills and Toxic Chemicals

Some 44,000 oil fields worldwide, illegal extraction, and leaks in refineries and oil-pipelines have led to an estimated five million oil-contaminated sites globally. Fuels and crude oil contain a wide range of pollutants, among them polycyclic aromatic hydrocarbons (PAH’s), one of the most worrying pollutants of our age. They kill flora and fauna, damage organs, and can cause cancer in humans and animals. Back in 1998, scientists had already found that mushrooms—specifically oyster mushrooms—do grow on heavily oil-contaminated soils. After 8 weeks, the total amount of contaminants in the soil plummeted by 99%, with PAH’s also broken down into less toxic substances. Fungi function by degrading organic pollutants (like fuel oils, which originate from dead organic matter) with the same enzyme they use to degrade wood and leaves. Contaminants are chopped into smaller compounds which are less harmful or not dangerous at all, so they can become part of the nutrient cycle again. Some are degraded to CO2 or water. "The concept of introducing, going back to organisms, which naturally perform the role of the degradation and using them to degrade and wipe out pollutants in the environment is a very promising route."

The Chernobyl Experiment: Fungi and Radioactive Elements

But mycoremediation doesn’t end with organic matter. Fungi can also treat soils contaminated with arsenic, lead, and mercury from mining operations, or even radioactive elements. In 1986, a nuclear reactor meltdown and explosion in Chernobyl spread devastating radioactive contamination. In a trial near the nuclear reactor, Erika Kothe used fungi together with host plants. "We could show that strontium, which is even a radioactive element half of the bioavailable strontium could be taken up by the sunflower in the growth period of 12 weeks." Later, the plants can be cut down, burned, and the strontium-enriched ashes can be stored more safely, leaving the soil significantly cleaner. What the fungi do here is change the mobility of the elements, fixing them in the soil, absorbing them, or helping plants take them up. Samples taken to a Russian industrial site showed that fungi accumulated up to 40 times more nickel and copper than the soil they were growing in. The solutions for heavily polluted soil may therefore be right beneath our feet.

Barriers to Broad Mycoremediation: Scale and Specificity

But as promising as some experiments are, many also fail. "That means I have 10 different experimental setups and it went well in seven and it didn't go well in three or the other way around. So what should I do, I cannot put that as a basis of putting into action real remediation schemes as an authority." Treating soils with fungi is feasible in rather small areas. It’s cheaper and more eco-friendly than conventional methods like removing and burning the soil. However, it is not an easy method, especially when dealing with entire forests or mining regions. Ecosystems are unique, and translocated fungi from another area do not necessarily grow in them. Promoting local species that can do the job would be key, but this takes time and patience. Of course, fungi can also decompose any organic waste from agriculture and the food industry.

Sustainable Architecture: Growing the Buildings of the Future 

Fungi's power to degrade organic matter can also be harnessed to build the structures of our future—a home made of mycomaterials. This may sound strange, but in 2014, the architectural team “The Living” built a 12-meter-high tower in New York City using 10,000 bricks made of mycelium instead of stone, bricks, or concrete. "They're very inexpensive to produce. They can be grown and fabricated in almost any conditions. So they don't need specialized equipment. And then when you actually put these bricks out into the world, they're very strong, especially for their weight. But they're a lightweight brick," explains David Benjamin, who headed the project and is an Associate Professor for sustainable architecture at Columbia University.

Mycelium Bricks: A Low-Carbon Alternative to Concrete

The production of materials like concrete and steel for construction are responsible for roughly 10% of the world’s carbon dioxide emissions. The alternative uses agricultural waste that is often burned, contributing to air pollution (e.g., in Delhi during winter). For the tower, crop residues from corn fields were seeded with a fungus which feeds on them. Placed in a mould, the fungus mycelium colonized it entirely within a week, eating up all the agricultural waste. It dries into a solid brick form, creating a new and low-carbon building material. It is not flammable, and its insulation properties are extremely good—it doesn’t only match some concrete’s capabilities, but also those of standard polystyrene and plastic. Crucially, the bricks simply rot when the house is pulled down. "I can imagine scenarios where people all over the world, sometimes in resource constrained environments, are growing their own bricks. It's totally viable." The bricks aren’t as firm as concrete. However, by combining the mycelium with other compostable materials like bamboo, and designing a framework to distribute stresses evenly, scientists from the University of Karlsruhe showed that concrete’s advantage can be mitigated. "One of its biggest challenges is durability because this is a material where if it gets damaged or cut it has the potential to absorb moisture." This means that for realistic housing applications, future homes would need different layers, using mycomaterials as the core of a wall, but protecting them from moisture damage from the outside. While mycelium bricks aren’t firm enough to build a skyscraper yet, the potential for low-rise buildings is huge. Fungus thrives in almost every region and any climate, and with our growing population, the need for affordable and sustainable housing is growing as well. Fungus bricks could become a local and easy means of answering these demands.

Conclusion: Tapping into Their Secret Powers

With accelerating climate change and pollution putting increasing pressure on our ecosystems, methods to tackle environmental degradation are becoming more urgent than ever. In one way or the other, fungi will play a decisive role here. They’re essential to the health of our planet, and we need to make better use of their secret powers. The use of fungi goes back at least 6000 years, where ancient cultures used them for transcendental experiences and medicine; the discovery of using them in antibiotics was nothing short of revolutionary. We must now take the next step and use them to clean up the planet and build a sustainable future.