[Nasrudith]

Plastic is chemically inert which should raise the threshold quite significantly. The question that needs to be answered is "What does/would acute plastic poisoning even look like?" I am by no means an expert, but I wouldn't be surprised if mechanically it could lead to increased clotting for the same reason sediment clogs pipes.

Even if it requires 'macroplastics' concentrations to cause problems, inert still doesn't mean harmless. One example which comes to mind is that senescent cells are 'inert' compared to cancer cells and they appear to be responsible for /have a role in aging's damage to tissues.