Waxworm could be the answer to the world’s plastic problem
The global plastic bag pollution crisis could be solved by a waxworm capable of eating through the material at “uniquely high speeds”, scientists have announced.
Researchers have described the tiny caterpillar’s ability to break down even the toughest plastics as “extremely exciting” and said the discovery could be engineered into an environmentally friendly solution on an industrial scale. Around a trillion plastic bags are used around the world each year, of which a huge number find their way into the oceans or are discarded into landfill.
Commonly found living in bee hives, or harvested as fishing bait, the waxworm proved it could eat its way through polyethylene, which is no- toriously hard to break down, more than 1400 times faster than other organisms.
Scientists believe the creature has potent enzymes in its saliva or gut which attack plastic’s chemical bonds, in the same way they digest the complex wax found in hives.
The waxworm’s potential was discovered by accident when biologist and amateur beekeeper Dr Federica Bertocchini cleaned out her hives and placed the parasites in a plastic shopping bag. She soon noticed it had become riddled with holes.
To confirm it was not just the caterpillars’ chewing mechanism that was degrading the plastic, researchers “mashed up” some of the worms and smeared them on poly- ethylene bags, which achieved similar results.
“It’s extremely, extremely exciting because breaking down plastic has proved so challenging,” said Dr Paolo Bombelli from Cambridge University.
“If a single enzyme is responsible for this chemical process, its repro- duction on a large scale using biotechnological methods should be achievable.”
He said the most likely scenario was one whereby existing recycling plants could be adapted to biodegrade mass quantities of plastic using the enzyme or enzymes. But he added the enzymes could one day possibly be sprayed directly onto landfill sites or even infused into sea plants in order to degrade plastic already in the environment.
Polyethlylene is the most common plastic in the world and is primarily used for plastic bags and packaging.
The creatures transformed the polyethylene into an “unbonded” substance called ethylene glycoll.
Published in the journal Current Biology, the study says it is likely that digesting the beeswax found in hives involves breaking down similar types of chemical bonds. The beeswax on which the worms grow is composed of a rich diversity of compounds including fats, oils and some hormones.
Bertocchini, who led the research at CSIC, said: “We are planning to implement this finding into a viable way to get rid of plastic waste, working towards a solution to save our oceans, rivers, and all the environment from the unavoidable consequences of plastic accumulation.” Bombelli said any initiatives to biodegrade plastic had to come alongside efforts to prevent the use of it in the first place.