Can Mushrooms in your Backyard Really Eat Plastic?

Some fungi can use enzymes to break down plastic and turn it into organic matter

There are almost 4 to 5 million species of fungi that can help us in multiple ways! From delicacy to cleaning of soil impurities, mushrooms do it all. Recently, researchers have found out that some fungi have special powers - they can eat plastics and solve our plastic pollution crisis! Yes, you read it right! Read out below to learn more about these superheroes.

Should We Be Concerned About the Plastic Menace Around Us?

Yes! Undoubtedly, plastic pollution poses one of the most significant challenges to our planet. Plastics are toxic and dangerous as they don't decompose and can remain in nature for ages. When burnt, they release harmful gases, which are carcinogenic and also cause declination in the population of vultures.

Plastic pollution has been creating a huge problem for the environment and us

Also, over a some time, plastics break into very minute particles, causing microplastic pollution in oceans and soil. Studies have found out that humans consume around 2000 microplastics per year through salt. Read here to find out more about microplastic pollution.

For many years, scientists and researchers have been finding out various ways to mitigate the ever-growing plastic pollution.

We have been eating many types of mushrooms for many long years!

While we have been relishing tasty mushrooms for many years, scientists have found out that mushrooms use special enzymes to chomp down plastics like their favourite snack treat! Let's see the science behind this phenomenon.

The Science of Plastic-Eater Mushrooms

Mycoremediation is a process where fungi and bacteria break down pollutants

There is a method called bioremediation where some living organisms break down pollutants in the environment using biological processes such as metabolism and enzymatic reactions. Mycoremediation is a type of bioremediation where bacteria and fungi disintegrate the contaminants in nature. Mushrooms use their enzymes in the mycoremediation process.

Interesting Discoveries About Plastic-Eater Mushrooms

In 2011, scientists discovered an endophytic fungus called a Pestalotiopsis microspora that contains bacteria responsible for degrading synthetic plastic polymers. This fungus can also survive in dark, oxygen-free environments, too! Thus, this makes itself an ideal candidate for dealing with plastic dominated landfill areas. They also observed that these light brown mushrooms significantly decomposed the plastic and turned it into organic matter in 2 weeks.

Oyster mushrooms can disintegrate PET plastic

Another interesting species of mushroom is Pleurotus ostreatus and Pleurotus pulmonarius, a type of oyster mushrooms that break down PET plastic ( Polyethylene Terephthalate) in 1 to 2 months. Researchers also further claim that these oyster mushrooms can still be edible. Thus, such species can solve food security and plastic waste issues.

In Fungi Mutarium, a vegetative thread like part called mycelium is used to degrade plastic | Source : LIVIN Studio

Fungi Mutarium is a prototype that grows edible fungal biomass, mainly the mycelium, as a novel food product | Source: L I V I N Studio

Katharine Unger, a designer from LIVIN Studio, collaborated with the microbiology department of Utrecht University for a project called the Fungi Mutarium. They used a thread-like vegetative part (mycelium) of two common edible mushrooms- Pleurotus ostreatus (oyster mushroom) and Schizophyllum commune (split Gill mushroom) for this experiment.

After a few months, they realised that the fungi had completely disintegrated small plastic pieces while growing around pods of edible agar. Thus, it can definitely help in combating microplastic pollution.

In 2017, Shehroon Khan, along with his research team at the World Agroforestry Centre in Kunming, China, found out another interesting species of fungus in a landfill of Islamabad, Pakistan. This fungus called Aspergillus tubingenesis can inhabit and grow on polyester polyurethane (PU) and can eventually decompose it into several small plastic fragments.

In a recent study published in the Journal of Hazardous Materials by researchers at the Royal Botanic Gardens (2021), a diverse microbiome comprising plastic-eating fungi and bacteria was unearthed in the coastal sea marshes of Jiangsu, China. The international team of scientists identified 155 fungal species responsible for degrading polycaprolactone (PCL), a biodegradable polyester utilized in various polyurethane productions.

Additionally, scientists from the University of Sydney have made a significant discovery: two types of fungi, namely Aspergillus terreus and Engyodontium album, can completely degrade small samples of polypropylene in just 140 days.

Polypropylene is commonly found in ice cream tubs, takeaway containers, and cling films. Professor Ali Abbas, a chemical engineering professor, supervised this research and emphasized its importance in the scientific community. He noted that this study represents the highest degradation rate reported worldwide.

Moreover, researchers from the Swiss Federal Institute WSL made a groundbreaking discovery involving 15 types of fungi found in Greenland, Svalbard, and Switzerland. These fungi were cultivated in a laboratory under dark conditions at 15°C to test their ability to degrade plastic.

Surprisingly, two types of fungi from the genera Neodevriesia and Lachnellula (whose names are yet to be determined) were able to degrade all tested plastics except for polyethylene (PE). The tested plastics included non-biodegradable PE, biodegradable polyurethane (PU), and two other biodegradable plastic mixtures: polybutylene adipate terephthalate (PBAT) and polylactic acid (PLA).

Previous studies have indicated that the mycoremediation process is most effective at an average temperature of 30°C. However, in this case, these fungi were effective at 15°C, demonstrating an energy-efficient method for plastic decomposition.

To Eat or Not to Eat?

To my surprise, many scientists have stated that certain types of plastic mushrooms are edible. In fact, Katharine Unger of Utrecht University stated that these mushrooms tasted sweet and smell like anise.

It is best to refrain from consuming plastic eating mushrooms until concrete research has been conducted

However, a study conducted in the University of Rajasthan, India, mentioned that such mushrooms can sometimes absorb too many pollutants, and thus, it would be toxic to eat them.

In my opinion, it is best to refrain from consuming them until concrete research has been conducted.

Can These Mushrooms Alone Help Us to Fight Plastic Pollution?

Certainly not. We simply can not transfer our responsibilities to these tiny organisms and go on using plastics. We should be very careful with our choices and should approach sustainability. There should also be strict government policies on the usage of plastic.

While extensive research is underway on these fungi, we have yet to find a solution to the plastic problem in aquatic environments. The process of collecting tons of debris from the ocean and relying on mycoremediation may prove to be costly.

However, our scientific community is committed to finding sustainable solutions to combat plastic pollution. Who knows, there may soon be a discovery of fungi capable of consuming plastic in the waters!