Since the 1950s, humans have created over nine billion tonnes of plastic. A total of 9% has been recycled, while only 12% has been incinerated. This leaves a whopping 79% of plastic waste that is piling up on landfills, the natural environment and oceans.
In an effort to lighten this load, researchers are seeking alternative measures of reducing plastic waste and its negative environmental impacts. This has led to deeper research into the possibility of using fungi to eat plastic.
Yes, you read that correctly: scientists are looking into using mushrooms to eat polyurethane, the main ingredient in plastic products.
Rare discovery in Ecuador
There are between two and four million different species of mushroom, and while some are rare, others can be found at your nearest supermarket.
In 2011, Yale students on a class research trip discovered a rare mushroom in the Amazonian rainforest in Ecuador. The fungus, called Pestalotiopsis microspora, can grow on polyurethane and consume it as its sole source of carbon.
After some study, the Yale research team found that this aesthically insignificant plant can survive in environments without oxygen. It can also break down and digest polyurethane while turning it into organic matter.
The research team also conducted a study to see what sort of fungus can consume plastic the fastest, and Pestalotiopsis microspora cleared polyurethane even more swiftly than Aspergillus niger, the fungus that causes black mold.
A 2014 collaboration made headlines when designer Katharina Unger of LIVIN Studio and the microbiology faculty of Utrecht University in the Netherlands made use of mycelium, which is the fungi counterpart of a traditional plant root system, to turn plastic into human-grade food.
They used oyster and split gill mushrooms in the experiment, and the mushrooms were cultivated in pods made of gelatin and filled with UV-treated plastics.
The gelatin was derived from seaweed.
The process which mushrooms use to break down or isolate contaminants from the environment is called mycoremediation.
Further exploration needed
While Yale’s study did not examine whether the plastic-degrading mushrooms were edible after breaking down polyurethane, the LIVIN Studio project concluded that the mushrooms it used were edible even after consuming plastic.
Speaking to Dezeen, Unger says the mushrooms had a sweet quality similar to the taste of star anise or liquorice.
Research reflects that there are mushrooms that can break plastic down in mere weeks or months, and may become a particularly protein-rich source of food for humans, animals and plants.