I’m not usually a conspiracy theorist, but I have a sneaking suspicion that all these biodegradable corn-plastic foodware items are a scam. I don’t necessarily think the claims they make are false — I think, given the right conditions, bioplastics will eventually return to the soil. But replacing recyclable plastics with biodegradable ones is pernicious because most people won’t give these things the conditions they need to decompose effectively. Throwing something in the landfill is not the same as composting it, and I’m afraid that’s where the large majority of bioplastic products will end up — in landfills, where entombed newspapers are still readable after 30 years.
Also, looking at this supposedly biodegradable cup, I’m bewildered as to what organism could break it down. I certainly can’t eat it. I could potentially eat paper, or leaves (not that I’d derive any nutritional value from them). I could eat most of the stuff that goes into compost. But not this.
So, in order to investigate what really happens when bioplastics get thrown away, I’m keeping one of these cups under semioptimal decomposition conditions – in a shallow grave in my backyard, where it will get exposure to moisture, oxygen, and all sorts of organisms. We will see how long it takes.