This may be about to change. Last year a group of Yale students visited the Ecuador rainforest as part of a course. They returned with samples of the fungus Pestalotiopsis microspora - whose favorite food turned out to be polyurethane. The fungus, unlike their other plastic-eating peers, could even do so under anaerobic conditions. Experiments in the laboratory revealed that a ten-day old Pestalotiopsis microspora could devour a quart of polyurethane in only a few days.

And, as it needs no oxygen to do so, bioremediation - the use of microorganism metabolism to remove pollutants – even in oxygen-deprived landfill conditions, offers distinct possibilities. Bioremediation is nothing new: microbes are currently happily digesting the oil spilled in the Golf of Mexico in 2012, and the wreck of the Titanic is slowly being eaten by rust-loving micro-organisms. Until now, however, polyurethane was not part of the menu.

The students and their professor published their findings in Applied and Environmental Microbiology, and are now looking for other fungi able to digest other plastics – such as polystyrene – as well.