The study, published in the journal Microbial Ecology, is the first large-scale global assessment of the potential for bacteria to degrade plastics.
Using environmental DNA samples from around the world, researchers scanned millions of genes and found 30,000 enzymes that could degrade ten types of plastic. Nearly 60% of these had not been previously discovered.
The researchers found more of these enzymes in microbes living in places with higher levels of plastic pollution, and the enzymes matched the type of plastics found in that location, suggesting that the earth’s microbiome is already evolving as a response. “Our study thus uncovers the earth microbiome's potential to degrade plastics, providing evidence of a measurable effect of plastic pollution on the global microbial ecology,” they conclude.
The information could help inform strategies to support biodegradation, which the researchers describe as a “plausible route” for sustainably managing the millions of tonnes of plastic waste that have accumulated in terrestrial and marine environments.
Plastic pollution is one of the biggest environmental concerns among the UK public, and is likely to intensify in the coming years. DEFRA is soon to consult on banning a range of plastic items, but will have to tackle the tricky issue of degradation.