The Grumpy Old Man

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.....A Possible Solution to the Plastics Disposal Problem.....

.....Could this little caterpillar be a key to disposing of all this waste plastic beginning to clutter the world.....

I found writing about the plastics problem extremely annoying, and in many ways distressing as we, as a species, are abusing our privilege as custodians of our delicate and beautiful planet. So often we chase a goal of financial gain through a potentially disastrous worship of "growth". But more of that in later grumps.

It is less than a month since I published the original grump on plastics but recently I came across an article in a recent issue of "New Scientist" suggesting there may be a glimmer of hope, albeit very tenuous. Like many scientific discoveries this one was, I imagine, heralded not with a shriek of "Eureka" but more with a hand on chin musing of "mmmmmmm........... that's interesting".

It appears that researchers in Cantabria, Spain were removing caterpillars of the Galleria Mellonella moth from beehives and noticed that the little darlings had a taste for plastic. The caterpillars were probably being collected in a plastic bag and decided to do a runner by eating their way out!

Subsequent tests found that a hundred of these caterpillars could consume 92 mg of plastic in half a day. (That's about 3% of your average supermarket shopping bag). That is bloody fast when one considers that natural decomposition is thought to take anything from one hundred to four hundred and fifty years to do the same job.

To ensure that the caterpillars were digesting and not just chewing the bags up creating nurdles, the team made a paste of caterpillars and spread it on polyethylene film. Within 14 hours, this paste had broken down some 13% of the plastic producing traces of ethylene glycol, a known product of polyethylene decomposition.

It is believed that this is the first scientific work showing this species is capable of decomposing polyethylene. (With the size of the plastic problems around the world I believe this observation to be an appalling indictment of man's greed)

It is thought, and research is still at an early stage, that the caterpillars produce an enzyme in their gut which is capable of decomposing plastic.

This would appear to be cutting edge as scientists at Stanford University in the USA observed that the paste acts much faster degrading polyethylene than anything previously isolated. Thus believing there may be a totally new and unknown mechanism at work.

Both groups of scientists are hoping that a single enzyme can be identified capable of breaking down plastic. If this is the case it may be possible to produce it on an industrial scale and use it to biodegrade plastics.

Grumpy believes this work provides a glimmer of hope, but it does mean that the plastic will need to be collected, segregated into its different types before processing. Clearly much of this can be done by the user of the item, but it still leaves vast quantities of plastic already discarded, sculling around and polluting the environment, particularly our oceans. It certainly does not solve the problem of nurdles i.e. particles that have already been ground up and are already causing serious environmental pollution.

There is hope, but the road Grumpy sees, although long and lumpy, is one that must be travelled.