Plastic is an organic material, trees are mostly plastic (lignin, a phenolic polymer, cellulose a polysaccharide polymer, hemicellulose an heteropolysaccharide and suberin a polyester-like polymer).

The problem we're having is a naturalistic fallacy crossed with the unpleasant fact that almost everything we touch sheds dust and powder absolutely everywhere. This along with spores and yeast and other dusts constantly enter our bodies.

Plastic is only of note because we made it.

Any problems beyond that is speculative and will requires ginormous gobs of grant money to actually answer with anything than precautionary principle-based FUD.