Scientists Identify a Worm That Can Digest Plastic
A recent discovery that a certain species of worm will digest plastic has given scientists hope that there may be a solution to the worldwide problem of plastic bag pollution.
Professor Federica Bertocchini, of the Institute of Biomedicine and Biotechnology of Cantabria in Spain, and also an amateur beekeeper, made the discovery when cleaning out a hive that had been infested by waxworms.
The parasitic worm is the larval phase of the wax moth, which lays its eggs inside beehives and the larvae feed on the wax honeycombs as they grow.
After clearing out some of the worms and placing them into a plastic bag, Prof. Bertocchini discovered they were eating themselves out of the bags at a very rapid pace.
Together with Paolo Bombelli and Christopher Howe of the University of Cambridge, 100 worms were exposed to supermarket shopping bags and the results suggest that not only did the worms eat the bags, but the plastic was digested and completely biodegraded.
Plastic bags are made from a chemical compound known as polyethylene (PE). The chemical bond within the PE compound is so strong that it can take more than 100 years for even the smallest bags to degrade, and much longer in others. As many divers will know, plastic bags have become a scourge on the marine environment.
"Plastic is a global problem. Nowadays waste can be found everywhere, including in rivers and oceans. Polyethylene in particular is very resistant, and as such is very difficult to degrade naturally', said Prof Bertocchini.
A previous study by scientists at Stanford University in America had shown that mealworms were capable of digesting PE, but the findings suggested that the plastic was degraded by bacteria in the gut of the worm, not by the worm’s digestive system itself.
Although the precise mechanism by which the plastic is broken down by the wax worm is not yet known, as Prof Bertocchini explains: "There is a possibility that an enzyme is responsible. The next step is to detect, isolate, and produce this enzyme in vitro on an industrial scale. In this way, we can begin to successfully eliminate this highly resistant material.'
If successful, the research may provide a game-changing attack on the levels of worldwide plastic pollution. It might not be able to clean up the ocean, but it could certainly stop discarded plastic from getting there in the first place.