Plastic is a form of carbon and therefore a potential source of food, but most plastics are highly resistant to degradation which is one reason they are so useful. For example, the predicted lifetime of a polyethylene terephthalate (PET) bottle is between 16 and 48 years.
However, this long lifetime results in huge amounts of plastic pollution. Mankind produces about 300 million tons of plastic every year of which about 14 million tons of plastic end up in the world’s oceans. Plastic pollution now pervades the planet, from the summit of Mount Everest to the deepest oceans.
United Nations Environment Programme (UNEP) estimates that half the plastic we produce is designed to be used only once. See here for more information.
But a paper published by the American Society for Microbiology in October 2021 written by a team led by Jan Zrimec from Chalmers University of Technology, Gothenburg, Sweden has found evidence that bacteria are evolving to degrade plastics. They have identified over 30,000 enzymes produced by bacteria able to degrade plastic.
The next step could be to use some of these enzymes to degrade plastic on an industrial scale and so reduce the vast amount of plastic pollution found everywhere on Earth. The Guardian explains that many plastics are currently hard to degrade and recycle. Using enzymes to rapidly break down plastics into their building blocks would enable new products to be made from old ones, cutting the need for virgin plastic production. The new research provides many new enzymes to be investigated and adapted for industrial use.