It's true that F isn't a good leaving group, but that's a double edged sword. By the same token, continuous exposure means that when it is occasionally substitu

It's true that F isn't a good leaving group, but that's a double edged sword. By the same token, continuous exposure means that when it is occasionally substituted into organic molecules throughout the body, it will be not easily substituted out. I am curious now what the equilibrium retention point is for typical fluoridation levels.