Mushrooms: Nature's Plastic-Fighting Superheroes

Mushrooms have been used for centuries for their beneficial properties. Now, they are being recognised for their ability to break down plastic, which could be a game-changing solution to the global plastic waste crisis. Certain species of mushrooms can break down plastic into organic matter, reducing plastic waste by 40-60% in just a few weeks. This process, known as mycoremediation, is a form of bioremediation that uses fungi to break down environmental pollutants. The discovery of plastic-eating mushrooms has opened up new possibilities for waste management and bioremediation, offering a sustainable solution to address the pressing issue of plastic pollution.

Mushrooms can break down plastic in landfills

Mushrooms, or more specifically, certain species of fungi, have been found to break down plastic in landfills. This discovery has offered a potential solution to the global plastic waste crisis.

The Problem of Plastic Pollution

Since the 1950s, 8.3 billion tons of plastic have been produced, with 40% used for packaging and discarded after one use. Landfills in the United States alone receive about 27 million tons of plastic annually. Plastic does not naturally decompose; instead, it breaks down into smaller pieces, or microplastics, which can take centuries to break down. These microplastics infiltrate ecosystems and the food chain, posing a danger to wildlife and human health.

The Power of Mushrooms

Fungi are natural decomposers, breaking down organic matter using enzymes. Some species of fungi have been found to break down much tougher materials, including plastic. These decomposer fungi produce enzymes such as peroxidases and laccases, which can break down the long polymer chains found in plastics.

Plastic-Eating Mushrooms

Two species of fungi have been found to be particularly effective at breaking down plastic: Pestalotiopsis microspora and Aspergillus tubingensis.

Pestalotiopsis microspora, discovered in the rainforests of Ecuador, can break down polyurethane, a common type of plastic, in both oxygenated and oxygen-free environments. It can also break down plastic in liquid and soil suspensions, making it ideal for use in landfills and waste treatment centres.

Aspergillus tubingensis, discovered in a dump site in Pakistan, can break down polyester in a few weeks by secreting enzymes that break the chemical bonds in plastic.

Practical Applications

The use of plastic-eating mushrooms has enormous potential for waste management, including landfill bioremediation, wastewater treatment, and sustainable manufacturing.

However, there are challenges to overcome, such as specific growing conditions, variable decomposition rates, and potential environmental impacts.

While mushrooms may not be the sole answer to our waste problem, they offer a promising biological solution that warrants further research and testing.

Oyster mushrooms can remove E. coli from contaminated water

Oyster mushrooms, or Pleurotus ostreatus, are an incredibly versatile type of fungi for mycoremediation purposes. They can be used to purify water through their ability to remove contaminants from both water and soil.

One lab-based study found that oyster mushroom mycelia were able to remove E. coli from water with a 99.25% success rate over a 96-hour period. The study used water that was inoculated with E. coli in a lab, as well as water straight from the Chicago River.

Oyster mushrooms have also been used to filter farm water runoff, clearing it of toxic contaminants. They can also be used to remove harmful pollutants from water sources affected by wildfires, such as toxic ash residue, heavy metals, harmful Polycyclic Aromatic Hydrocarbons (PAHs), and even TNT.

In addition to their water-purifying capabilities, oyster mushrooms can also be used to remove plastic-related pollutants from the soil. They are one of several species of fungi that have been identified with the ability to degrade plastics and PAHs.

Plastic-eating mushrooms can be used in home composting systems

Plastic-eating mushrooms, or more specifically, the process of mycoremediation, can be a game-changer for home composting systems. Mycoremediation is a form of bioremediation that uses fungi to break down environmental pollutants. Mushrooms, or rather, the thread-like root systems of fungi called mycelia, consume food externally by using their enzymes to break down molecules in pollutants and toxins.

The Pestalotiopsis genus of fungi, and more specifically, the Pestalotiopsis microspora, discovered in the Amazon rainforest in Ecuador, can degrade a common type of polymer plastic called polyester polyurethane (PUR) and convert it into organic matter. The Yale University researchers who studied it found that it could survive and feed on PUR in anaerobic conditions, making it an ideal candidate for use in landfills and home composting systems.

Austrian designer Katharina Unger, in collaboration with Utrecht University in the Netherlands, developed the Fungi Mutarium, which uses pods of agar gelatine to nourish the fungus with sugars and starch until UV-treated plastic is stuffed into the middle. After a few months, the fungus fully digests the plastic, leaving a puffy, mushroom-like cup with a sweet taste and a liquorice smell. Scientists foresee households owning smaller-scale versions of the Fungi Mutarium to recycle their plastic waste.

Another species of plastic-eating mushroom, the oyster mushroom (Pleurotus ostreatus), was found capable of degrading PET (Polyethylene Terephthalate) plastic over 30 to 60 days. PET is commonly used to make plastic water bottles, and only a small percentage of these bottles are recycled. A trial conducted by Fungi Solutions in Melbourne found that oyster mushrooms could break down most toxins and the microplastics in cigarette butts, one of the top items of plastic waste found in the ocean, within seven days.

The use of plastic-eating mushrooms in home composting systems offers an innovative and natural approach to addressing the global plastic waste crisis. However, it is important to note that releasing new organisms into new environments can have unforeseen effects on local ecosystems. Therefore, further research and testing are needed to ensure the safe and effective use of plastic-eating mushrooms in home composting systems.

Mushrooms can be used to create sustainable building materials

Mushrooms are proving to be a good alternative to more polluting construction materials. Materials made with mycelium, the fungal network from which mushrooms grow, produce far less planet-heating carbon dioxide than traditional materials like cement. An added bonus is that mushrooms are biodegradable, so they leave behind less harmful waste than traditional building materials.

Mycelium is a network of fungus fibres that usually grow underground and can sprout mushrooms above ground. Because it grows so quickly and easily, mycelium can be used to sustainably create all kinds of materials, including packaging material, fabrics, bricks, and insulation.

In 2014, assistant professor Joe Dahmen and his partner Amber Frid-Jimenez, Canada Research Chair in Design and Technology at Emily Carr University of Art and Design, worked on an architectural installation fabricated from recycled polystyrene blocks. They decided to explore more eco-friendly options and discovered the world of mycelium biocomposites, an emerging field in which mushroom roots, or mycelium, grow in loose cellulosic material such as sawdust. The results are durable materials with attributes similar to polystyrene foams.

In 2016, Dahmen and Frid-Jimenez, through the University of British Columbia's social ecological economic development studies (SEEDS) sustainability program, worked with university students and staff to develop a scalable method of producing mycelium biocomposites using two local materials: oyster mushroom spores and alder sawdust. They installed six new stylish benches outside the UBC Bookstore, assembled from light-coloured honeycomb-shaped bricks under a top of clear acrylic. The benches are not only an eye-catching spot for students to relax, but they're also very much alive, grown from a blend of oyster mushroom spores and alder sawdust packed into moulds.

Another mycelium-based design project is the MY-CO SPACE by the MY-CO-X collective of artists, designers, and biotechnologists. This construction used mycelium bricks in combination with plywood to create a space for people to enter and explore. The space was on display in Frankfurt during the summer of 2024.

Projects like these demonstrate some of the possible uses of mycelium, which in turn can inspire new commercial products. The main reason for switching an existing product, such as packing material, to a mycelium version is that mycelium has a very low environmental footprint. It can be produced locally, using local organic waste, and it grows quickly, making it easy to produce large amounts. Because it can be grown on waste, it doesn’t divert soil from agricultural needs, and it repurposes waste by weaving the mycelium network through it to create a new material.

While designers and artists are experimenting with new uses of mycelium, it’s already found its way into several commercial products. Over the next few years, you’re likely to find more mushroom-based materials in buildings, packaging, fashion, and other places.

Mushrooms can be used to create sustainable textiles

The use of mushrooms in textiles is not limited to clothing. Eben Bayer and Gavin McIntyre of Evocative Design created flip-flops that are 100% biodegradable. They also developed Greensulate, an organic, fire-resistant board made of water, flour, oyster mushroom spores and a mineral called Perlite, which can be used as an insulation board.

Mushrooms can also be used to create biodegradable alternatives to conventional plastics. For example, Austrian designer Katharina Unger and scientists from Utrecht University in the Netherlands created the Fungi Mutarium, which uses pods of agar gelatine to nourish the fungus with sugars and starch until UV-treated plastic is stuffed into the middle. After a few months, the fungus fully digests the plastic, leaving a puffy, mushroom-like cup with a sweet taste and a liquorice smell.

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