Juno, Ala., also saw a steep increase in childhood tooth decay after the city removed fluoride from its water in 2007. One University of Alaska Anchorage study estimated each child incurred an extra $300 in dental bills per year following the removal.

Florida is poised to become the second state to ban fluoride in public drinking water, over the concerns of dentists and public health advocates who say the mineral is a safe, effective way to protect people of all ages from developing cavities.