Heavy metal content of black teas from south India

Tea is the most popular beverage in the world. Since tea contains several essential nutrients, drinking of tea is considered beneficial for human health. The presence of heavy metals in trace level in tea has received special attention because they are directly related to health. A basket survey was conducted in the tea districts of south India to generate a data base on the presence of heavy metals in black tea. A total of one hundred black tea samples, collected from the tea growing regions of Valparai and Nilgiris in Tamil Nadu, Vandiperiyar, Wayanad and Munnar in Kerala and Karnataka state were analyzed for heavy metals. The results of analysis showed that the mean level of Cu was 24.07 ± 2.25 mg kg−1, Cr 4.76 ± 1.27 mg kg−1, Ni 2.53 ± 1.01 mg kg−1, Cd 0.14 ± 0.06 mg kg−1 and 0.81 ± 0.32 mg kg−1. Under the Prevention of Food Adulteration Act (PFA) of India the tolerance limits have been fixed only for copper and lead. The present database could be used for fixing tolerance limits of the other heavy metals in tea. The contents of copper and lead in tea were below the permissible limit under the PFA act.