Can Mushrooms Clean Toxic Waste? Mycoremediation Explained

Think you know everything there is to know about mushrooms? Think again.

The humble ‘shroom is well known for its nutrient-rich profile, delicious taste and low caloric content… but just how much do you know about its bioremediation abilities? As it turns out, mushrooms aren’t just great for our bodies but are pretty important for the earth too. And by pretty important, we mean exceptionally important, in that they can actually help to decontaminate the environment, break down plastics and clean toxic waste.

You see, mycoremediation refers to the clean up and decontamination of the environment using mushrooms. 

Mycore-what? 

Ok, but before we jump right into mycoremediation, let’s briefly chat about remediation and bioremediation. Remediation is a process of reversing or stopping environmental damage, with bioremediation using living organisms to do so. In the bioremediation process, organisms such as bacteria, fungi or algae detoxify polluted soils and water by helping to degrade or immobilize any nasty substances present.

Okay, now what is the mycoremediation definition?

Pollution continues to be an ongoing concern, with scientists anticipating fifty per cent of the world to be using contaminated water by the year 2025. In addition to its threat on drinking water, pollution can also threaten food security and agriculture growth, as well as a bunch of other nasty stuff. 

Obviously, pollution = bad, and while there are heaps of physical and chemical methods available for the removal of harmful chemicals from soil and water, these techniques can be expensive and produce toxic by-products… so what else is there to do?

Enter the noble mushroom. 

Shy, hidden and misunderstood, the mushroom is often disliked for its decomposing abilities. A lot of the time, humans focus only on the troublemakers causing plant or human disease, and are quick to banish any that may show up in the garden or around the house. But generally speaking, the vast majority of fungi really just want to hang out, maybe break down some organic matter and not kill or destroy anything. We swear they really are fun guys.

So, bioremediation with fungi is called mycoremediation, which specifically involves the removal of toxic compounds using mushrooms. Mycoremediation is still a fairly new prospect, but has proven to be an economical, eco-friendly and effective strategy to help combat the ever-increasing issue of water and soil pollution.

Nature’s Great Decomposers.

Okay, we know that mushrooms have the capability to cleanse the earth’s toxins… but how on earth do they actually do it?

Well, it’s all in the enzymes. Think of the last time you saw a wild mushroom- did you notice the white, thread-like hyphae (they kinda look like roots)? Well, this is known as the mycelium- the vegetative state of the mushroom that work to send out the enzymes needed to help break down chemicals within the surrounding environment. Just like they can break down the Earth’s plant and woody material, saprophytic fungi can use their digestive enzymes to break down complex chemicals like hydrocarbons (naturally occurring compounds that form the basis of crude oils, natural gasses) and pesticides. Okay so now that we know a little bit more about the basics, let’s get into the fun stuff- what can the mighty ‘shroom actually break down?

Mycoremediation of soil

Fungi features as one of Nature’s most important allies- its agency of waste decomposition and symbiotic relationship with trees and plants make it an essential component of the soil food web. In the forest, there are plants that struggle to grow directly upon the fallen leaf litter. And these plants rely on the fungus’ decomposition of the leaves to release the nutrients needed for plant growth. As the fungus breaks down the wood and leafy litter, a rich substance called ‘humus’ is formed, which provides a softer and more hospital environment for plants to grow. So that’s all naturally occurring bioremediation- what about the mycoremediation of toxic materials within the soil? Let’s get the dirty details.

Bioremediation works to subdue toxic organic materials (eg. From oil spills, pesticides and industrial waste) at the molecular level by converting them to less harmful chemical compounds. The ultimate goal here is the full mineralization of the contaminants and the transformation of them to your friendly chemicals, CO2, H2O, and N2 etc. While heavy metals and radioactive waste cannot necessarily be decomposed by mycoremediation, they can be deconcentrated (which basically means, make them less harmful). They may also be physically removed from the soil by harvesting the fungus.

In the last 15 years, mushrooms have been used in soil decontamination efforts all over the world. They have been used to clear boat fuel pollution in Denmark, contaminated soil in New Zealand, as well as toxic debris left in California’s 2017 wildfires. What’s more, they’re currently being used in a mushroom oil spill clean up relief project at the site of one of the largest global oil spills within the Amazon.

Mycoremediation of water and plastic eating mushrooms…

They’re now estimating that there could be more plastic in our oceans than fish by the year 2050.

In 2011, Yale students discovered a fungus in Ecuador, Pestalotiopsis microspore, which has the ability to break down and digest plastic… Yep, there is a fungi that eats plastic. Its ability to do so even in an anaerobic (air-free) environment means that it may even be effective based at the bottom of landfill! The discovery of this immediately prompted the development of more research and it was found that the mycelium of two very common edible mushrooms, Oyster mushrooms (Pleurotus ostreatus) and Split gill mushrooms (Schizophyllum commune) could be used to fully degrade small pieces of plastic, too. Over a couple of months, the fungi essentially replaced the plastic with pods of edible agar… turning plastic into a small mycelium snack!

Mushrooms can also be added to your grey water system or placed in the path of a contaminated stream In water-contaminated areas, burlap sacks can even be filed with straw, cardboard, coffee grounds and mushroom spawn to help intercept and filter contaminated water.

So, why aren’t we using mycoremediation more?

As exciting as this all sounds, mycoremediation is still a fairly new concept that’s yet to be fully explored. Globally, India, South Korea and the Phillipeans have the most advanced knowledge about mycoremediation, while the rest of us are still, admittedly, a little behind.

Although, we can’t help but be optimistic. Because if there’s anything that tickles our fancy, it’s the use of natural organisms to help cleanse the earth.