Scientists have developed a self-digesting plastic", which, they say, could help reduce pollution. Polyurethane is used in everything from phone cases to trainers, but is tricky to recycle and mainly ends up in landfill. However, researchers have come up with a sci-fi like solution. By incorporating spores of plastic-eating bacteria they've developed a plastic that can self-destruct. The spores remain dormant during the useful lifetime of the plastic, but spring back to life and start to digest the product when exposed to nutrients in compost. There's hope "we can mitigate plastic pollution in nature", said researcher Han Sol Kim, of the University of California San Diego, La Jolla. And there might be an added advantage in that the spores increase the toughness of the plastic. "Our process makes the materials more rugged, so it extends its useful lifetime," said co-researcher, Jon Pokorski. "And then, when it's done, we're able to eliminate it from the environment, regardless of how it's disposed." The plastic is currently being worked on at the laboratory bench but could be in the real world within a few years, with the help of a manufacturer, he added. The type of bacteria added to the plastic is Bacillus subtilis, widely used as a food additive and a probiotic. Crucially, the bacteria has to be genetically engineered to be able to withstand the very high temperatures needed to make plastic.