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.

The CDC says fluoridation is among the 10 greatest public health achievements of the 20th century. Utah recently became the first state to ban it.

State lawmakers voted for the bill that would prohibit local governments from adding fluoride to water. Supporters argue that the government should not decide whether fluoride is added to water. While opponents of the measure say it helps prevent cavities.