The closest, I think, is copper. https://www.ars.usda.gov/arsuserfiles/80400525/articles/ndbc32_watermin.pdf https://www.ars.usda.gov/arsuserfiles/80400525/art

The closest, I think, is copper. https://www.ars.usda.gov/arsuserfiles/80400525/articles/ndbc32_watermin.pdf https://www.ars.usda.gov/arsuserfiles/80400525/articles/ndbc... There is no US RDA for fluoride.