A comparison of two systems for measuring water fluoride ion level.

The purpose of this study was to assess the reliability of measurements of fluoride ion concentrations as determined by the Orion fluoride meter and electrodes (Orion models SA 720 meter, 94-09, 90-01-00, and SA 720 meter, Orion Research Incorporated, Laboratory Products Group, Boston, MA) and to reference electrodes with a digital meter and the Hach colorimeter (DR100 colorimeter, Hach Company, Loveland, CO). Three groups of drinking water samples were collected simultaneously from each of 53 elementary schools in Oxford County, Ontario, Canada. Samples in Groups 1 and 2 were analyzed for fluoride at the University of Western Ontario using the colorimetric method and the specific ion electrode system respectively. Samples in Group 3 were analyzed at the Ontario Ministry of the Environment laboratories; these results were used as the "gold standard." The overall results of the study suggest that with proper calibration the colorimeter system may be a valid, reliable, and affordable tool for fluoride analysis in the dental office.