Bacteria Can Use Plastic Waste as a Food Source, Which Isn't as Good as It Sounds - ScienceAlert

Experiments in the lab have now shown that a species of marine bacterium, known as Rhodococcus ruber, can slowly break down and digest plastic made from polyethylene (PE).

Used largely in packaging, PE is the most commonly produced plastic in the world, and while it's not clear if R. ruber munches on this waste in the wild, the new research confirms it is at least capable of doing so.

"This is the first time we have proven in this way that bacteria actually digest plastic into CO2 and other molecules," says microbial ecologist Maaike Goudriaan from the Royal Netherlands Institute for Sea Research (NIOZ).

By measuring levels of an isotope of carbon released from disintegrating plastic called carbon-13, the authors estimated the polymers in their experiments broke down at a rate of about 1.2 percent a year.

The team can't be sure how much the UV lamp decayed the plastic compared to the activity of the microbes, but the bacteria were clearly playing a role.

"Our data show that sunlight could thus have degraded a substantial amount of all the floating plastic that has been littered into the oceans since the 1950s," says microbiologist Annalisa Delre.