title: A new perspective on metals and other contaminants in fluoridation chemicals.
abstract: BACKGROUND
  Fluoride additives contain metal contaminants that must be diluted to meet drinking water regulations. However, each raw additive batch supplied to water facilities does not come labeled with concentrations per contaminant. This omission distorts exposure profiles and the risks associated with accidents and routine use.
  
  
  OBJECTIVE
  This study provides an independent determination of the metal content of raw fluoride products.
  
  
  METHODS
  Metal concentrations were analyzed in three hydrofluorosilicic acid (HFS) and four sodium fluoride (NaF) samples using inductively coupled plasma-atomic emission spectrometry. Arsenic levels were confirmed using graphite furnace atomic absorption analysis.
  
  
  RESULTS
  Results show that metal content varies with batch, and all HFS samples contained arsenic (4·9-56·0 ppm) or arsenic in addition to lead (10·3 ppm). Two NaF samples contained barium (13·3-18·0 ppm) instead. All HFS (212-415 ppm) and NaF (3312-3630 ppm) additives contained a surprising amount of aluminum.
  
  
  CONCLUSIONS
  Such contaminant content creates a regulatory blind spot that jeopardizes any safe use of fluoride additives.
authors.forename: Phyllis J
authors.initials: PJ
authors.lastname: Mullenix
mesh_terms: D001151:Arsenic / Q000032:analysis; D060766:Drinking Water / Q000737:chemistry*; D005457:Fluoridation; D005459:Fluorides / Q000737:chemistry*; D006801:Humans; D008670:Metals / Q000032:analysis*; D012824:Silicic Acid / Q000737:chemistry*; D012969:Sodium Fluoride / Q000737:chemistry*; D013054:Spectrophotometry, Atomic
chemical_list: D060766:Drinking Water; D008670:Metals; D012824:Silicic Acid; C035291:hexafluorosilicic acid; D012969:Sodium Fluoride; D001151:Arsenic; D005459:Fluorides
keywords: Drinking water regulations; Fluoride additives,; Metal contaminants,