Enzymes found in the saliva of larvae can rapidly break down one of the world’s most commonly used plastics, opening up a way to combat this form of pollution, according to a study published Tuesday.
Around a third of the 400 million tons of plastics that are produced annually according to OECD estimates are polyethylene. Obtained from the petrochemical industry, easy and inexpensive to produce, they are used particularly frequently for packaging.
The UN, which describes plastic pollution as a global scourge, recently started negotiations to develop an international agreement to curb the phenomenon.
The fact that certain enzymes can attack plastics has already been documented, but over a long period of time.
Two enzymes present in the saliva of wax moth (Galleria mellonella) larvae attack polyethylene in just a few hours at ambient temperature, according to work by a Spanish team of researchers, published in Nature Communications.
Federica Bertocchini of the Margarita Salas Center for Biological Studies in Madrid, lead author of the study and an amateur beekeeper, explained that she came up with the idea for this research by cleaning beehives stored for the winter whose wax combs had been colonized by these larvae.
After cleaning the hives, she placed the larvae in a plastic bag and soon found that it was “full of holes.”
“The question was, do they (the larvae) eat it or is there a chemical process? We checked the lab and found the polyethylene had oxidized,” she told AFP.
Not quite to the point
Many additional studies and experiments will be necessary to fully understand the process before considering a concrete application of the discovery, the researchers point out.
But Federica Bertocchini is already imagining various uses against plastic pollution.
“The enzymes could be incorporated into a liquid solution and poured onto plastic at the recycling center,” or used in remote locations where collection or recycling is difficult, or even in individual households to break down their own waste.