How does one know that the clinical aberrations being called "fluorosis" by Dr. Eugenio Beltrán-Aguilar and colleagues in "Prevalence and Trends in Enamel Fluorosis in the United States from the 1930s to the 1980s" (February JADA) are being caused by exposure to fluoride? So many things could be doing it.
And if it is exposure to fluoride, how do we know it isnt the kind of fluoride being eaten and imbibed and assimilatednatural vs. sodium vs. the kind in municipal water supplies?
How do we know it isnt a combination of factors and fluoride is just one of the factors?