crystalline silica is an iarc group 1 carcinogen, the highest-concern category, and occupational illnesses due to crystalline silica exposure have been well known for thousands of years
When I built my home I used concrete floors that I then kept waxed. It seemed like the best solution I could find. But then we had to cover the floors with wool rugs because the acoustics were painful.
wool is pretty great; the worst you can say about it is that it's a mild allergen and kind of expensive
just to disambiguate, though, the risk of silica exposure from walking around on a concrete floor, or even sweeping it, is not worth worrying about. i wouldn't clean it with a leaf blower though