Canadian researchers have made a discovery that could change how we think about plastic waste. A team at Brandon University in Manitoba has found that waxworm caterpillars, the larvae of the greater wax moth, can eat and digest polyethylene plastic bags in less than a day.
Polyethylene is the world’s most common type of plastic, used in everything from grocery bags to food packaging. It is known for being strong and resistant to natural breakdown. Normally, it can take decades or even hundreds of years for this plastic to fully decompose. But these small caterpillars, often called waxworms, can chew through it in just 24 hours.
The research, presented at the Society for Experimental Biology Annual Conference in Antwerp, Belgium, shows that around 2,000 waxworms can eat a full plastic bag in just one day. That is a huge difference compared to how long it normally takes in nature.
Dr. Bryan Cassone, Professor of Insect Pest and Vector Biology at Brandon University, explained the process, “Around 2,000 waxworms can break down an entire polyethylene bag in as little as 24 hours, although we believe that co-supplementation with feeding stimulants like sugars can reduce the number of worms considerably,” he said.
When the caterpillars eat plastic, it does not just pass through their bodies. They actually turn it into fat stored inside their system. “This is similar to us eating steak – if we consume too much saturated and unsaturated fat, it becomes stored in adipose tissue as lipid reserves, rather than being used as energy,” Cassone explained.
Even though the caterpillars can eat and process plastic, the research also showed that a diet of only plastic is deadly for them. The waxworms grow weaker and lose weight quickly if they eat only plastic. Within a few days, they die.
“They do not survive more than a few days on a plastic-only diet and they lose considerable mass,” Cassone said. “However, we are optimistic that we can formulate a co-supplementation that not only restores their fitness to natural levels but exceeds it.”
To fix this issue, the team is now testing supplements, such as sugars, that can be given to the caterpillars along with plastic. The goal is to keep them alive and healthy while they continue breaking down polyethylene waste.
Plastic pollution has become one of the world’s most serious environmental problems. Every year, more than 57 million tonnes of plastic are thrown away. Much of it ends up in landfills, oceans, and rivers, where it stays for hundreds of years. Tiny fragments, called microplastics, have even been found on Mount Everest, in the deepest oceans, and inside human organs.
Scientists around the world are searching for new ways to fight this problem. Waxworms may provide a natural answer. Dr. Cassone believes there are two main ways this research could be used. “Firstly, we could mass rear waxworms on a co-supplemented polyethylene diet as part of a circular economy,” he said. “Secondly, we could explore the re-engineering of the plastic biodegradation pathway outside the animal.”
This means that soon, researchers may be able to use the biological process inside waxworms without needing the insects themselves. There is also another benefit.
If waxworms are raised on a large scale, they could become an important food source for fish farming. “Our preliminary data suggests that they could become part of a very nutritious diet for commercial food fishes,” Cassone explained.
This shows that waxworms could both reduce plastic pollution and help provide food for aquaculture, creating a double advantage. One study found that Each year, the world produces more than 100 million tonnes of polyethylene. To handle even a fraction of that, billions of waxworms would be needed.
Another concern is that waxworms naturally eat beeswax. If their populations were grown in large numbers, they could become a serious threat to bee colonies, which are already under pressure worldwide. Scientists warn that any large-scale use of these insects would need strict control.
Even with these challenges, the research has attracted international attention. It shows that living creatures may hold the key to solving problems caused by human-made materials.
While waxworms alone cannot fix the global plastic crisis, they may inspire new methods to handle plastic waste. By learning more about the bacteria and enzymes in their digestive system, scientists hope to design safe and scalable ways to break down plastics quickly.
