The University of Sydney experiment is one more study that shows how plastic can be broken down by things like fungi, bacteria, enzymes, and algae.


Two types of fungi can be used to attack small samples of polypropylene plastic, which is used to make items like takeaway containers, ice cream tubs and cling film, according to experiments carried out by researchers at the University of Sydney and published in the scientific journal npj Materials Degradation.

The most resistant plastic, polypropylene in the world has been broken down by Australian scientists using backyard fungi; they hope that this discovery will soon ease the pressure on the world’s recycling crisis.

Aspergillus terreus and Engyodontium album, the two fungi, are typically found in soil and plants. After the samples were exposed to heat or ultraviolet rays, it took the fungi 90 days to break down 27% of the polypropylene plastic tested and about 140 days to completely degrade it.

The research team was led by professor of chemical engineering Ali Abbas, who deemed the results important. According to our knowledge, it has the highest reported degradation rate in the literature.

Despite being recyclable, an estimated 13,500 tonnes of polypropylene plastic are dumped in landfills in Australia each year due to contamination or mixing. Because the same techniques were already being used in various fields, Professor Abbas said he was “very confident” the technology could be scaled up to process thousands of tonnes of plastic annually.

He explained that it was scaling up, which is very similar to any fermentation process. We can now apply the knowledge from chemical process engineering to this specific process because the technology for those processes already exists. Researchers’ biggest challenge will be to broaden any potential solution to the nation’s growing soft plastic waste.

The failure of Australia’s national REDcycle programme in 2017 exposed serious issues with the country’s plastic recycling infrastructure and left the majority of Australians without a way to recycle soft plastic. Now, scientists will work to speed up and improve the degradation process by adjusting crucial elements like temperatures, plastic particle size, and fungus usage.

According to Professor Abbas, the process could be scaled up in three to five years. Or even earlier, if the investment was prepared and ready for us to accelerate that, he added.

Could a solution really be found in five years?

Paul Harvey, an environmental scientist and authority on the world’s plastic pollution who was not involved in the study, said that we could. According to Dr. Harvey, “that is a fairly typical time frame for standing-start research through to commercialization.” It could and ought to happen even sooner, he said.

Given the enormous problems with waste management and plastic pollution management that we have on a global scale, Dr. Harvey said that there is really no reason why this type of research can’t be accelerated.

So does this mean I can use as much plastic as I want?

The professionals say without a doubt. Dr. Harvey stated that Australia still required numerous methods to manage waste and plastic pollution because the environmental crisis was only going to get worse despite the fact that the technology was still a few years away.

According to a paper from 2020 that was published in ACS Sustainable Chemistry and Engineering, 400 million tonnes of plastic waste are produced annually by humans.

Of that, about 175 million tonnes end up in landfills or pollute the environment. That much would be sufficient to reconstruct a 6,000 km section of the Great Wall of China every year. plates, takeaway containers and bags made of plastic.

“We have an addiction to plastic and we’re not getting any better at kicking that addiction,” Dr. Harvey said.

“As a nation, we don’t seem to comprehend the gravity of the plastic pollution issue we are facing.” And we don’t seem to understand that we must reduce our plastic waste because there isn’t enough space in landfills for it, we lack strategies for managing plastic waste, and we produce way too much of it.” The head of the University of Sydney team, Professor Abbas, concurred.

“We must take action now; we cannot afford to wait. “As we previously stated, the technology itself might be ready in the following years. But doing so won’t be sufficient to resolve the issue.

“We need to address the behavioural issues, the social issues, the business issues, and other issues related to the plastics problem. The technology is only a portion of the answer.”

What’s the next step? 

The researchers from the University of Sydney are currently working on proof of concept, or evidence that their solution is workable. To achieve this, they will construct a “bench-scale prototype,” which allows them to test chemical reactions on a small scale.

According to Professor Abbas, “that’s the chemical engineering work we do in scaling up and allowing us to prove the process at scale technically, economically, and environmentally before we can carry that out in the commercial scale.” “So we can see clearer how close we are to a commercial-ready plant as we develop the technology over the next, say, five years.”

What could this solution look like?

Dr. Harvey says it’s unlikely that the fungi will be offered as a finished good at a hardware store. “You might see them being used in large-scale industrial or commercial applications, so that might be in municipal waste management facilities,” he continued.

The vast majority of Australians want to recycle their waste, but due to our fragile recycling infrastructure, it is incredibly difficult to manage the massive amounts of waste we produce. Additionally, that technology might have a big impact on regional Australia.

If a town can treat its waste stockpiles with a fungus, bacteria, or enzyme and transform it into a lower mass stockpile despite having very limited waste management infrastructure, Dr. Harvey said, “that’s a great thing.” Additionally, it means that they can dispose of their waste locally.

How to process and treat the massive amount of waste that is produced in areas with very low populations but a significant amount of waste that still needs to be managed presents one of the biggest challenges outside of metro and city areas. In this area, a lot of research is being done.

The University of Sydney experiment is one more study that shows how plastic can be broken down by things like fungi, bacteria, enzymes, and algae. But there is also a lot of work being done on incineration and pyrolysis, which is the burning of materials.

“While we are producing energy from burning the waste, Dr. Harvey said, “that’s worrying in and of itself because it’s not really a sensible use of resources because it’s kind of like burning fossil fuels.”

That will help reduce the amount of waste that enters the environment, it also produces a by-product that is problematic in and of itself. Accordingly, while it will reduce waste entering the environment, I don’t think it’s a long-term solution.”

Researchers have discovered that a “superworm,” a larva of a beetle that eats polystyrene, can gain weight by only eating polystyrene. Colin Jackson from the Australian National University says that should be taken into account by researchers in the fungi experiment.

There needs to be a discussion about whether polypropylene or polystyrene plastic  should be recycled or broken down by fungi, according to Dr. Jackson, who is also the chief science officer at a private company that uses enzymes to break down plastics before remaking them.

This is due to the potential release of greenhouse gases if the plastic changes from its solid state, where all the carbon is trapped, to being essentially converted to CO2, according to Dr. Jackson.

“That again needs to be balanced because you’re stopping the production of new plastic, which also produces a significant amount of carbon dioxide. So it’s not necessarily a bad thing, but more circular solutions where the carbon is recycled back into plastic might be better in terms of greenhouse gases.”