I think plastics are one of those things where, dumped into a random place, they probably won't be biodegraded. However, for any given plastic, there is probabl

I think plastics are one of those things where, dumped into a random place, they probably won't be biodegraded. However, for any given plastic, there is probably some organism in existence which will eat it under some or all conditions. So the usage of "biodegradable" maybe depends on which viewpoint you are interested in. For example, here's the wiki on polyethylene, which seems like the typical plastic for "plastic bags" from a store: https://en.wikipedia.org/wiki/Polyethylene#Biodegrading_plastics https://en.wikipedia.org/wiki/Polyethylene#Biodegrading_plas...