

The American Dental Association is probably who you’re looking for. The fda and usda don’t regulate toothbrushes in that sense so you’re not really goi g to get a legally required disclosure like you do with say tooth paste. The ADA will have a seal or mark they put on products they deem safe via testing.
https://www.ada.org/resources/research/science/ada-seal-of-acceptance
This is like 5 terrible ideas in a trench coat.