This is how Fluoride was introduced to America.
https://www.sciencehistory.org/distillations/pipe-dreams-americas-fluoride-controversy
Pipe Dreams: America’s Fluoride Controversy | Science History Institute
The fluoridation era dawned sleepily enough in America. On the afternoon of January 25, 1945, municipal workers at the Grand Rapids, Michigan, waterworks began feeding powdered sodium fluoride into a system of basins, hoppers, filters, and tanks. The powder dissolved into the water supply and flowed..
https://www.sciencehistory.org/distillations/pipe-dreams-americas-fluoride-controversy