Page 42 - Plastics News May 2017

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Biochemists find out biological answer to plastic pollution

The caterpillars worm has turned plastic bags into syrup making it a simple option for addressing
plastics pollution

iochemists in Madrid and Cambridge have found that the University of Cambridge’s Department of Biochemistry
Bcaterpillars of the Greater Wax Moth eat carrier bags, to conduct a timed experiment.
leading to a simple biological answer to plastic pollution.
They placed a hundred wax worms on a plastic bag, and
The larva could be used to solve the problem of plastic holes started to appear after just 40 minutes, and after
bag and sheet pollution, or their gut bacteria could be 12 hours there was a reduction in plastic mass of 92mg
mass produced to destroy polyethylene. from the bag.

The caterpillars are offspring of the Greater Wax Moth, Scientists say that the degradation rate is extremely fast
a moth common across Asia and Europe which is bred for compared to other recent discoveries, such as bacteria
angling bait. The larvae, or Wax Worms, live as parasites reported last year to biodegrade some plastics at a rate
in honey bee colonies in the wild, and are the bane of
beekeepers as they hatch and grow on beeswax. Both
beeswax and organic ethylene are ultimately derivations
of palmitic acid, and the similarity of structures allows
the caterpillar to produce an agent that breaks the
chemical bond.

of just 0.13mg a day. Polyethylene takes between 100
and 400 years to degrade in landfill sites.

The researchers conducted spectroscopic analysis to show
the broken chemical plastic bonds. The larva transformed
the polyethylene into ethylene glycol, a monomer, which
can be used as raw materials to make PET.
Federica Bertocchini, an amateur beekeeper, discovered To confirm it wasn’t just the chewing mechanism of the
the effects of the larva by accident after removing them caterpillars degrading the plastic, the team mashed up
from her hives and placing them in a shopping bag, which some of the worms and smeared them on polyethylene
was soon riddled with holes. She said: “Wax is a polymer, bags, with similar results.
a sort of ‘natural plastic,’ and has a chemical structure
not dissimilar to polyethylene.” Bertocchini concluded: “We are planning to implement
this finding into a viable way to get rid of plastic waste,
After noticing the caterpillar’s appetite for plastic, she set working towards a solution to save our oceans, rivers, and
up an experiment with Paolo Bombelli from the Spanish all the environment from the unavoidable consequences
National Research Council (CSIC) and Christopher Howe at
of plastic accumulation.”

Plastics News | May 2017 42