Analysis of fluoride in locally available beverages: Comparison of direct, oven diffusion and hexamethyldisiloxane diffusion methods

Abstract

Analysis of fluoride in a variety of beverages was carried out using three different methods inconjunction with a fluoride ion selective electrode. The three methods gave comparable results for 26samples of fruit juices. However, 68% of the juices were found to contain fluoride levels higher than theWHO recommended limits (0.6 - 1.0 mgl-1). Soft drinks (sodas) and beers were found to contain values lower than 0.6 mgl-1. The amount of fluoride in tea infusion was found to increase both with increase inboiling time and amount of tea leaves used. Chocolate and coffee infusions were found to contain 4.3 mgl-1and 4.0 mgl-1fluoride, respectively