Fluoride assay methodology for carbonated beverages.

Purpose: The purpose of this paper was to review different methodological techniques used for the assessment offluoride in carbonated beverages, and compare results using a fluoride ion electrode direct read method with and without a prior decarbonation treatment. Methods: The carbonated beverages in this study were either purchased locally at grocery stores in Iowa City, Iowa, or purchased as part of a national representative sampling approach included in the National Fluoride Database and Intake Assessment Study (NFDIAS). The samples were compared with and without a decarbonating process. Soda pop and beer samples were analyzed by removing a 1-ml sample and adding a 1-ml buffer solution. The fluoride concentration of the sample and buffer combination was then determined using a fluoride ion specific electrode. Results: There was no significant difference in the fluoride concentration of the samples with or without prior decarbonation. The mean absolute difference between the soda pop group with and without decarbonation was 0.01 ppm F, while results from the beer samples showed variation of 0.00 to 0.02 parts per million fluoride (ppm F). These differences were not statistically significant for the soda pop or beer groups (P=.50 and P=.74, respectively). Conclusion: Whether or not decarbonation was conducted prior to analysis, the fluoride assay results were the same. Therefore, decarbonation of soda pop and beer was deemed unnecessary prior to fluoride analysis.