> I currently get the distinct impression that polymer-digesting microbes are not currently considered dangerous, with the current impacts being negligible.

Well, you've just answered it. I would like to know the scientific rationale for this or an opposing belief. I currently have no opinion on the matter because I haven't read any material to think about in any way other than "these things exist".

I'm not referring to this article - I'm referring to the general case of plastic-eating microbes. Plastic eating organisms are not new. Even certain types of mealworms will eat styrofoam...

Articles like these are published several times a year, but I don't think I've seen any studies on the potential impact.

This article mentions it, but there are no accompanying references.

http://theconversation.com/how-plastic-eating-bacteria-actua...