450 years – that’s how long it takes for a PET bottle to decompose naturally, or rather, that’s how long it takes for a PET bottle to break down into little pieces of plastic. And with huge amounts of plastic waste ending up in the sea every day, this is a problem we’ve known about for a long time. But Mother Nature wouldn’t be Mother Nature, if she didn’t find her own ways for dealing with problems just like this: according to the magazine Science, Japanese researchers have discovered a naturally-occurring species of bacteria that seems to destroy PET (polyethylene terephthalate) completely.
The bacterium, which was discovered in a recycling centre, has been christened Ideonella Sakaiensis, named after the town where it was found. Its daily diet is primarily made up of PET plastic (commonly found in things like plastic bottles and synthetic clothing fibres), which it consumes and even uses to obtain energy. Carbon dioxide and oxygen are generated during the decomposition process, and what remains at the end is terephthalic acid and glycol, both of which are non-toxic to the environment and can be recycled.
But the whole process takes quite a long time – so long, in fact, that at this stage it won’t (yet) be able to offer a solution to the worldwide waste problem. Six weeks – that’s how long the bacteria need to eat through a piece of PET that’s the same thickness as sellotape. Might this change in the future? It’s difficult to know.
For now it seems like teenager Boyan Slat’s ocean cleanup array might offer a more effective solution to the problem of plastic in our oceans.
70 Year Evolution
PET has been around for about 70 years. So the fact that the bacteria have been able to develop so much within this time is evidence of an incredibly fast process of evolution, and researchers are currently looking into how it could have happened so quickly. And if this species of bacteria likes munching on PET, we can’t rule out the possibility of other types existing that might be able to degrade other types of plastics.
A lot of research still needs to be done before we’ll be able to use ideonella sakaiensis effectively in the recycling process. But even if it doesn’t signal an end to the problem of plastic waste, this discovery is an important step in the recycling of PET, as well as being an incredible testament to the power of nature to evolve and tackle whatever we humans throw at it.
This article has been translated from the original by Hanadi which appeared on our German-language platform.