In this specific case, very unlikely that plastics as a whole cause cancer due to some structural form issue. Saying ‘microplastics’, to compare to asbestos, is

In this specific case, very unlikely that plastics as a whole cause cancer due to some structural form issue. Saying ‘microplastics’, to compare to asbestos, is similar to saying ‘silicon’. Asbestos is a particular form of crystalline tube shaped silica (aka silicon dioxide). Many other forms of silicon are both cancer causing, and completely inert. I suspect plastics will similarly have only small portions that are really nasty. We’re making a huge variety of novel types though every day. Which is part of the concern. what we call ‘plastic’ has such a huge variety of molecular weights and compositions it’s like trying to find common ground between say nickel, stainless steel, and uranium. We already know some plastics cause cancer, and some precursors to the same plastics cause cancer. And a bigger issue IMO is plasticizers which modify the plastics structure to make them more malleable and less brittle.