The ocean is full of plastic, a grim marker of the Anthropocene. There are floating, continent-size patches of it in the Pacific and Atlantic Oceans, and there are newly formed ones in the Arctic. There are some uninhabited islands that are drowning in the stuff.
Weirdly, though, scientists have come to the conclusion that, based on the amount of plastic we make every year, there is only about one-hundredth as much of the plastic floating around as the numbers would suggest. Although there are many possible explanations for this, a new study available on the pre-print server bioRxiv has concluded that microbes are breaking the plastic down.
This may sound utterly bizarre, but just last year, researchers discovered that a newly discovered species of bacteria was able to shatter the molecular bonds of polyethylene terephthalate (PET), one of the most common forms of plastic. They’re literally using it as a food source.
Normally, PET takes 450 years to completely degrade in the environment. These bacteria make short work of it in just six weeks. It’s this information that has led to a team of researchers from the Pompeu Fabra University in Barcelona to suspect that the lack of plastic in the oceans is largely down to these microscopic critters.
Using mathematical modeling, they have come to the conclusion that other geological processes or counting errors cannot explain the discrepancy between the global rate of plastic production and its “underwhelming” presence at sea. It's somewhat circumstantial, but it's a solid idea.
At a glance, this seems like good news – a growing number of plastic-consuming microbes will help limit the absolutely disgraceful amounts of plastic that’s dumped into the ocean, much of which is consumed by animals that die, or survive long enough to be eaten by us. However, you’d have to be quite morally repugnant to suggests that this means we can keep dumping plastic in the oceans without consequence.
Still, if these bacteria can be encouraged to proliferate across the ocean, it would reduce humanity’s negative impact on them, and few would claim that this is a bad idea.
We perhaps shouldn’t rely on these bacteria too heavily, though – it’s possible that plenty of the plastic is sinking down beneath the surface and being buried within the seafloor. Ultimately, this will resurface again as a bizarre new rock type some have called a “plastiobreccia”. Either way, it’s difficult to trace it all.
In any case, we are still dumping a horrific amount of plastic into the oceans at present. Although recycling has its place, things arguably won’t change until plastic is phased out in favor of bioplastic, the type that quickly breaks down in any environment after it has been used.
[H/T: New Scientist]