Determination of Fluoride Content in Tea Infusions Sold in Karachi Using Fluoride Ion Selective Electrode

Fluoride intake is recognized to be important for dental health. Potentiometric analysis of fluoride content ion (F^–) in solutions by using fluoride ion-selective electrode is simple, reliable and cheap. Very small concentrations of fluoride-ions (10^-6 mol.dm^-3 ) can be determined by fluoride selective electrode. The purpose of this study was to estimate the fluoride contents in various commercially available tea infusions with a specific focus on risk of dental caries and flurosis. 100 mL of 44 different tea brands were kept at boiling temperature and fluoride concentrations were measured at 5, 10 and 15 min using ion selective electrode. In case of tea bags tea infusions were analyzed for fluoride at 5 min after introducing tea bag in boiling water with no further heating. After 5 min at boiling temperature, the mean fluoride concentration for black, green and herbal tea infusions were 1.51 – 7.97, 1.22 – 5.94 and 0.08 – 0.16 respectively.