Dietary Content and Evaluation of Metals in Four Types of Tea (White, Black, Red and Green) Consumed by the Population of the Canary Islands

Abstract

Objective: The aim of this study was to analyze the contents of Cd, Co, Cr, Cu, Fe, Mg, Ni, Pb, Zn in samples of four types of tea (Camellia sinensis) consumed in the Canary Islands: white, black, red and green tea, in order to determine their intake through consumption. Methods: A total of 80 samples (20 of each type of tea) were analyzed by ICP-OES. Results: The highest concentrations of Cd, Co, Mg, Pb and Zn were found in samples of white tea, those of Cr, Fe and Ni in the red tea, and those of Cu in green tea. While the lowest levels of Cd, Co, Fe, Pb and Zn were found in black tea, those of Cr, Mg and Ni in the green tea, and those of Cu in the white tea. Conclusion: The calculated intakes of each metal (assuming the consumption of a cup of tea 2 g/ day) shows that Cr, Cu, Fe, Mg and Zn make a negligible contribution to the RDI, and the same applies to Cd to the PTMI and Pb to the PTWI.