我剛查了一下，根據2020年數據，全美有73%的人的飲水中加了氟

Roughly 73% of the U.S. population with public water access in 2020 received drinking water with fluoride adjusted to the “optimal” concentration of 0.7 milligrams per liter, according to the CDC.

At least a dozen states have laws mandating that larger communities fluoridate. Among them are California, Delaware, Georgia, Illinois, Kentucky, Louisiana, Minnesota, Mississippi, Nebraska, Nevada, Ohio and South Dakota.

Yet lawmakers in three of those states — Georgia, Kentucky and Nebraska — have filed bills that would reverse the mandates and leave the choice up to a local voter referendum or to the governing body of local water systems.

Three states — Maine, New Hampshire and Utah — require a public vote for fluoridation by municipalities and their public water systems.

波士頓的水也加了氟。據說即將上任的肯尼迪是反氟的。