Concentration of fluoride and selected other elements in teas
Wei, S.H.; Hattab, F.N.; Mellberg, J.R.
Nutrition 5(4): 237-240
1989
ISSN/ISBN: 0899-9007 PMID: 2520298 Document Number: 336772
Fluorine, phosphorus, calcium, aluminium, magnesium, manganese and zinc were estimated in infusions made from 15 Chinese, 11 Ceylon/Indian and 6 herb teas (1 g/100 ml deionized water at 85 degrees C). Chinese teas continued to release F throughout the first h of infusion, whereas release of F from Ceylon/Indian teas was essentially completed after 5 min. After a 15-min infusion, the mean F concentration in Chinese teas was 1.73 mg/kg, and in Ceylon/Indian teas it was 1.24 mg/kg. Herb teas contained a negligible amount of F (0.02 to 0.05 mg/kg). P and Mg were the most abundant of the other elements with an average of 12.5 and 9.1 mg/kg, respectively. A high correlation was found between the released F and Al. The total F content in tea leaves ranged from 82 to 371 mg/kg. The addition of milk to tea infusions did not appreciably reduce the F concentration. The estimated daily F intake from tea infusion made with fluoridated water at 0.7 mg/kg is 1.05 mg.