Also, one of the more interesting points from the article is this statement: "Virtually no human studies in this field have been conducted in the U.S."
Why would I ignore it when it proves my point? You're basing your conclusions off of China studies where the levels of fluoride they consider to be "high concentrations" are 3-60x the MAXIMUM amount ever used to fluoridate drinking water in the U.S. Ergo, application of such results to the U.S. tap water situation is ignorant at best and disingenuous at worst.