Lead and cadmium levels in tea traded in the metropolitan area of Belo Horizonte

Abstract

This research aims at evaluating the levels of lead and cadmium in industrialized and non-industrialized samples of tea traded in the metropolitan area of Belo Horizonte, due to the constant use of different kinds of tea by the Brazilians. Camomile and maté have been selected and analyzed as tea-infusion and digested-plant. The levels of Pb and Cd were determined by spectrometry of atomic absorption with graphite furnace and Zeeman background corrector. The average levels of Pb and Cd in samples of camomile and maté tea-infusion were below the values established by the Brazilian legislation for metals in soft drinks (0.2 mg/L). The concentrations of metals in plant-digested camomile samples (0.15 µg/g to Cd and 0.42 µg/g to Pb) and plant-digesgted mate samples (0.53 µg/g) were considered normal according to the literature with exception of Cd levels in plant-digested maté samples (2.59 µg/g). Difference was not found significant between the levels of quantified Cd and Pb in samples of industrialized and not industrialized tea-infusion camomile and maté teas. The concentrations of metals were higher in industrialized digested-plant camomile and maté, when compared with not industrialized. There was no significant difference among tea-infusion samples.