Researchers working for Carbios, a firm based in France, have created an enzyme which breaks down plastic.
The scientists believe the enzyme could eventually make plastics biodegradable.
The enzyme, PET hydrolase, is a bacterial enzyme which was found in a compost heap of leaves. Although PET can be recycled, parts of it may end up in landfill. This enzyme can break down plastic bottles into chemical parts, and then be used to manufacture other plastic bottles.
There are drawbacks, however, as PET bottles have to be processed, heated and ground-up before they can be broken down - which means an increased cost for the material.
It is hoped the enzyme will be produced on an industrial level by 2024.
The research has been published in the journal Nature.