[PH values and fluoride levels in some tea brands].

The purpose of the study was to determine the pH and fluoride levels in selected commercial tea brands sold in supermarkets and to evaluate the importance of tea as a dietary source of fluorine. Thirty six different brands and types of tea in bags were evaluated. In order to prepare the tea, one bag of tea (1.5-2 g) was covered with 200 mL of boiling deionized water for 3 minutes. The pH was measured with a pH-meter and fluoride concentration was determined with an ion-selective electrode (Orion 9609). pH values of the tea infusions ranged from 3.85 to 6.45 (mean 5.24) and fluorides from 0.12 ppm to 8.33 ppm (mean 1.32 ppm). Thus, the individual intake of fluorine is estimated at 0.66 mg per 500 mL of tea. The results confirm that regular consumption of tea is an important dietary source of fluorine.