There is no way to control the dose of a drug or natural health product once added to public water.
There is no way to give people of sound mind over the age of 18 the right of consent for consuming a drug or natural health product added to public water for the sole purpose of treating the health of the people consuming the water.
Right to consent & proper monitoring of fluoride intake are the simplest reasons for only allowing safety chemicals added to public water.

Many people now even choose fluoride free toothpaste. Those who want to swallow more fluoride than they are already absorbing from dental products & processed foods and drinks, can simply use fluoride supplements which cost $13 for a year's supply.

 
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