It's been done, and decades ago — Mutant 59: The Plastic Eaters by Kit Pedler and Gerry Davis (1971).
A new, highly-resistant plastic sold around the world for a variety of hostile-environment uses begins to fail in highly-public situations, causing deaths and panic. The company that created it was also working on a plastic that would decompose when exposed to a specific chemical, to address the buildup of plastic waste, and through the novel the characters come to believe that this is the source of the degradation of the supposedly resistant plastic. The actual cause is a scientist employed by a completely different company who, annoyed at the clogging of his pipes from plastic toys his kids throw down the toilet, wonders whether a bacterium could be created to eat the plastic and dissolve the obstructions; He comes up with a variant that does, but suffers a brain aneurysm, dropping the petri dish into the sink, where it breaks, releasing the strain into the sewers; it turns out that the decomposable plastic is a superfood for the bacterium, which mutates to eat more and more varieties of plastic, spreading first through the sewers and then elsewhere via all of the connected piping and wiring made from or sheathed in plastic.