Plastic is ubiquitous, indispensable and (unfortunately) relatively indestructible. In many ways, it is the defining product of the twentieth century – cheap to make, flexible in application, disposable – and its use in the twenty-first shows no signs of decreasing. At the same time, plastic is the bête noir of environmentalists; it’s that ‘disposable’ tag that marks it out. The planet is awash with unwanted plastic; the oceans are full of it (some researchers refer to it as an extra continent); the food chain is increasingly affected by it (nurdles*, it turns out, are no substitute for noodles); and until recently, there appeared to be nothing that would break it down and allow it to bio-degrade.
Over the last few years, however, scientists working in a number of different environments (as varied as urban landfill sites, coral reefs and ‘marine deserts’, and the world’s rain forests) have begun to discover a number of types and species of microbe that appear capable of metabolising plastic. This assortment of bugs (I shall refer to them from now on as ‘plastiphages’) and the wide spread of environments they inhabit, has prompted a lot of questions, and some optimism**.
The questions raised by this discovery are fascinating in themselves: since plastic is a fairly recent invention, have we chanced upon a whole class of micro-organisms capable of fast-track evolution? If not, what were they eating before plastic came along? Does this discovery imply that, somewhere in the vast planetary microbiome, there are tiny creatures that can eat just about anything, however hazardous or apparently indigestible?
More to the point, there is now, potentially, an answer to the problem of plastic in the environment (thus the optimism); if we can harness the powers of plastiphages, we can start to deal with the vast and unlovely legacy of twentieth-century technology in a practical, and hopefully permanent, way. Quite clearly, this field of enquiry contains huge commercial potential too; the company that comes up with a market-ready mini-beast, ready to tuck in to our most intractable waste problem, is a company with a fat future (and a ready-made marketing advantage to boot; this brand, on the face of it, is greener than grass).
However, there might just be a shadow or two lurking under the ecological/entrepreneurial gleam. The employment of plastiphages carries a hidden potential for blowback that might just be worse than the problem it is slated to cure.
A little thought on the ramifications of what is, on the surface, a benevolent example of bio-engineering, and a potential nightmare emerges. Plastic is practically everywhere on the planet, and we produce, and dispose of, more of it every day. The various species that feed on plastic have a growing environmental niche in prospect, and they will undoubtedly expand their populations. Plastic plastic everywhere, and a large population of plastiphages – think about it: effectively we have laid a continuous trail of waste plastic right around the world, and the trail leads right back to us, and the billions of plastic items we depend on every minute of every day. Imagine the consequences if ravenous mini-beasts go on the march.
If plastiphages made it to our urban centres in large numbers, they would disrupt every facet of life. The digital world depends for its physical existence on plastic; most of the utility items in your house have plastic components; hospitals use huge amounts of plastic; some of your clothes contain plastics; the greenest of households is awash in plastic; a good deal of the world is wrapped or sheathed or coated in plastic.
Presumably the people developing plastiphage strategies have thought about this (they have though about it, haven’t they?) and are looking at ways of containing, and possibly killing, their little helpers if necessary. The trouble is, that may not be so simple. Many plastics contain toxins (phthalates and BPA are the most well-known, but there are quite a number of others) so it is reasonable to assume that the microbes that eat them are fairly resistant to toxins; the extent of that resistance is crucial. How are we going to protect this material (the material which most connects the contemporary world to itself) if a robust, voracious plastiphage decides to come and live among us?
Perhaps worse, the scientists investigating plastiphages are not sure at this point if the microbes, when they ingest plastics, excrete natural and harmless substances, or environmental toxins. Again, this point is crucial; substituting one environmentally hazardous substance for what might turn out to be a whole host of others could easily turn a silver bullet into a poisoned chalice. We could find ourselves saddled with an invisible pest that not only eats our computers, but also makes us ill.
It would be comforting to think that this is a problem for some distant dystopian future, but big fixes (even potential big fixes) have a momentum that is difficult to stop or control. It’s not hard to imagine how easily (and widely) plastiphages might be promoted. Throw a few into every landfill – greener and cleaner! Spray a few around the park, or popular tourist spots; clean up the countryside! Have a few as pets, to eat your baby’s disposable nappies! We could quite easily surf our way into hell on the back of an illusion of control.
The late George Carlin used to joke that nature evolved us as we are, to do the things we do, because the next phase of life was predicated on plastic (and in that phase, we would be the disposable items). Carlin’s joke may come to have an eerily prophetic ring about it. Some scientists are already using the term ‘plastisphere’ to describe what is, in effect, a new biome. How extensive, and potentially dominant, that biome turns out to be is a question fraught with anxiety. Funny to think that our dystopia du jour, being overtaken by thinking machines, might be undermined by a hungry bug …
*’Nurdles’ is the industry term for the tiny beads of plastic left when an item disintegrates
**You can read about some of those discoveries here