american dental association american medical association beijing bones bottled water bulgaria calcium canada centers for disease control and prevention chile china colorado conspiracy theory cryolite dna dental dental caries dental fluorosis dialysis digital object identifier dose-response relationship europe fluoridation by country fluoride fluoride poisoning fluoride therapy fluorine deficiency fluorosis genotoxicity health hexafluorosilicic acid illinois india indiana lead list of childhood diseases liver milk mineral mouth national research council new world order nutrition ohio open directory project osteosarcoma parts-per notation peru philippines pikes peak pork pubmed central radium skeletal fluorosis systematic review thailand united kingdom united states united states environmental protection agency world health organization