My bet is Hardi board will be the next one. Concrete dust causes silicosis. In industrial construction allowable concrete dust is basically zero. Residential construction people are sawing and grinding this concrete siding all the time.
Except there were scientific studies done at the time that "proved" it was safe, even as a cigarette filter. Can't really blame people for trusting that IMO.
Now I wonder what was actually so flawed about those studies.