We have a plastic problem; it’s harmful to life, lasts practically forever, and there’s too much of it. Of all the substances our civilization uses, plastic is the hardest to recycle. So much so, that a CBC investigation a few years back found that most recycling companies didn’t recycle the plastic, but either burned it (producing an even more toxic residue), or just sent it to the landfill. A fair chunk of Canada’s plastic has been shipped (illegally) to other countries for disposal, much to those countries’ displeasure. We’re finding plastic everywhere, from the oceans to the ice caps to even inside our bodies.
While some governments (including Canada) have begun to ban the use of single-use plastics like bags and packaging, there’s still enough plastic floating around to cause real harm to Earthly life. Is there some way we can deal with it all and get a cleaner world?
Well, if you can’t recycle the plastic conventionally, we may have to turn to unconventional means… like eating it. Science fiction’s toyed with this idea a few times since the 1970s, starting (to my knowledge at least) with the 1971 novel Mutant 59: The Plastic Eaters by Gerry Davis and Kit Pedlar. In the novel, a well-meaning scientist tries to create a bacterium that can consume plastic. Now scientists at the University of Queensland have found something similar: a worm capable of eating plastic.
This “superworm”, Zophobas morio, has special bacteria in its gut that produces certain enzymes which can break down polystyrene. As a result, the worm can not only survive eating plastic, but thrive in plastic-rich environments. The researchers are focused on the enzymes being used in the worm’s gut as a way forward for plastic recycling; if you can manufacture the enzymes on an industrial scale, plastic recycling and/or disposal becomes a lot easier and safer.
Which is all well and good, but I think this can lead to a more “low-tech” plastic disposal system. Simply cultivate the worms themselves in a closed environment and feed them plastic. The worms can only handle polystyrene right now, leaving a number of other plastics untouched, but it might be possible to engineer additional gut bacteria that can let the worms break down other plastics. One could imagine “plastic composting bins” in neighborhoods or private homes, slowly breaking down our bags and jugs and bottles.
One can also get a little more aggressive, by engineering gut bacteria in other species loose in the wild. I’m thinking especially of the oceans, where plastics are slowly choking the ecosystems there (in addition to overfishing and climate change). A few species that have habitat all throughout the oceans, fortified with modified gut bacteria, might help to clean them of our waste.
As for microplastics within the human body, one could imagine transplanting the genes responsible for these enzymes to either our gut bacteria or our macrophages, allowing us to dispose of any microplastics inhaled or ingested with a minimum of fuss. Alternately, a “plastic pill” might become possible, or maybe even enhancements to the liver and kidneys for natural filtration.
Of course, in Mutant 59, letting the plastic-eating life loose caused disaster, as the mutated microbes went everywhere plastic was in use, not just the trash heaps. Having the plastic-eating bacteria “packaged up” in lifeforms like the worms makes the problem of containment much easier to deal with. Still, one can imagine future pest problems when such plastic-munching worms get loose in a house, like termites. That might prompt plastic-making companies to make “inedible plastic” as a counter. Wherever this path leads us, we can be thankful for this discovery. It is not every day God hands us a solution to one of our persistent problems, gift-wrapped in a humble worm. Mutant 59, your day has come!