I've talked about this a lot on NT, the fluoride that is added to MOST U.S. city waters contains lead, much of it is a waste by-product from the lead, aluminum and fertilizer industries. This fluoride is NOT naturally occurring but from waste which "they" are converting into what is going in much of our waters. Don't drink or cook with tap waters. I do my best not to, our city fluoridated in 2009, actually "late" in this 6 decade practice.