Complex Made Simple

Fungi, robots, and bacteria are waging a war on plastics

For over 80 years, humans have created 9 billion tons of plastic, and this creates a crisis since plastic takes more than 400 years to degrade. Today, help is on the way thanks to fungi, bots, and bacteria

Scientists have discovered mushrooms that eat plastic A French ocean adventurer and a team of engineers designed a yacht that feeds on plastic waste for power Bacteria and fungi could one day provide a way to consume plastic waste material.

For over 80 years, humans have created 9 billion tons of plastic, and this creates a crisis since plastic takes more than 400 years to degrade. Earth is on track to have as much plastic in the ocean as fish by weight by 2050, according to one estimate.

How to get rid of it?

Plastic-eating fungi

From being used as construction material (making bricks) to biofuel, mushrooms could potentially aid humanity in getting rid of plastic

Scientists have discovered mushrooms that eat plastic. Some mushroom species have the ability to consume polyurethane, which is one of the main ingredients in plastic products.

In 2011, Yale students on a class research trip discovered a rare mushroom called Pestalotiopsis microspora in the Amazon rainforest which not only can grow on polyurethane but also use it as its one and only carbon source. 

The fact that it could digest and break down plastic even in anaerobic environments was exciting since it could be used at the bottom of landfills.

Further experiments on the speed of decomposition showed that Pestalotiopsis microspora cleared plastic faster than Aspergillus niger, which causes harmful black mold.  

In another study in 2017, scientists discovered a different mushroom called Aspergillus tubingensis that eats plastic in a waste disposal site in Pakistan. In two months, the fungus could colonize the plastic itself and secrete enzymes that break down polyester polyurethane into smaller pieces.

There is also “mycoremediation“, which is an experimental technique that harnesses mushrooms’ natural ability to use enzymes to break down foreign substances. This cheap, effective, and environmentally sound technique has been used to decontaminate the environment by using fungi to get rid of some contaminants from damaged ecosystems. 

Read: Abu Dhabi to be free of single-use plastic bags by 2021

Read: Will you eat forks, knives, trays, corks, wrappings to rid environment from plastics?

A yacht that loves plastic

A French ocean adventurer and a team of engineers designed a yacht that feeds on plastic waste for power, scooping up plastic garbage and converting it into fuel to help power the boat, a recent report by Reuters reveals.

Known as the SeaCleaners project, the 56-meters-long yacht is currently in the development and concept phase, with aims to have a working prototype by 2024.  

As the catamaran sails through the water, a conveyor belt will collect waste, organize it, and then feed it into a burner. The plastic will melt, producing gas that will drive a turbine, generating electricity for the ship’s motors, making it 70% self-sufficient through the use of plastic for power, alongside solar cells and wind turbines.

The team behind the project inferred that if 400 of the boats were made, they could clean up one-third of the plastic debris in the world’s oceans.

Ocean bots

A surge of new initiatives is aimed at clearing the oceans of plastic in recent years, the most famous of which is undeniably the Ocean Cleanup project.

Recent advances in robotics have seen university projects develop autonomous machines that could also help with the problem, such as the Floating Robots to Eliminate Debris (FRED) student project and the SeaClear initiative aimed at cleaning the ocean floor.

Some 10 million tons of plastic waste ending up in the ocean every year, according to the World Economic Forum

Plastic-eating bacteria

Polyethylene terephthalate (PET) is a material used in plastic bottles and many other products, including clothing, furnishings, and solar panels.  

PET does not break down easily, and an estimated 8 million tons of it ends up in the oceans annually. 

Recent discoveries by microbiologists around the world, however, have revealed that bacteria and fungi could one day provide a way to consume the waste material.

Research isolated a group of five bacteria that worked together to chop and consume PET.

The bacteria have adapted to PET as a food source. They produce various hydrolase enzymes that break down the complex polymer molecules within PET.

In March 2016, scientists in Japan published an extraordinary finding. They discovered bacteria that had developed the ability to decompose, or “eat,” plastic.

The bacteria, Ideonella sakaiensis, was only able to eat PET.  

Experts caution that large-scale commercial use of plastic-eating microorganisms is still years away, while their potential release in the environment, even if practical, could create more issues than it solves.

Moreover, since the scientists working on the issue are not really producing “products” that the masses sought after, the field doesn’t attract much investment.

In order to make any of these naturally occurring bacteria useful, they must be bioengineered to degrade plastic hundreds or thousands of times faster. 

In 2018, scientists in the U.K. and U.S. modified bacteria so that they could begin breaking down plastic in a matter of days. In October 2020, the process was improved further by combining the two different plastic-eating enzymes that the bacteria produced into one “super enzyme.”