Yes, fluoride is toxic, but it is difficult to detect as it creeps into you over the years, accumulate. Then one day you cant recall your neighbours name, your memory is blank.. And for many it is too late, when the brainfog set in. You dont know what hit you.
Iodine is an antidote to this, and the ones that accidently or not bump into this, consider yourself lucky. Yes, some tough answers, you called rude. Much of it would be easier if you came i to it with an open mind, and a respect for the place you visit.
Also better to use an avatar, posting history; instead of the number; as this is the way of the "trolls"