Heavy Metals Contents in Some Commercially available Coffee, Tea, and Cocoa Samples in Misurata City – Libya

Abstract

The purpose of the present study was to evaluate the concentrations of Mn, Cr, Fe, Cu, Zn, Pb, and Cd in 18 types of commercially available coffee, tea, and cocoa on Misurata city markets. The samples were dry digested and then measured by Microwave Plasma-Atomic Emission Spectrometry (MP-AES). The heavy elements levels were differed among the various types of analyzed samples. The concentrations of Mn were relatively higher than the other analyzed elements and varied between 1.0 – 673.3 mg/kg. The observed concentration ranges of the other elements, were as follows: Cr (0.1- 131.0 mg/kg), Fe (0.3 – 40.6 mg/kg), Cu (0.3 – 13.6 mg/kg), Zn (1.0 -20.9 mg/kg), Pb (1.8 – 4.4 mg/kg) and most Cd samples were below the instrument detection limits. The values determined for Mn, Cr, Fe, Cu, and Zn were lower than the maximum permissible limits. However, the concentrations of Pb were high according to the Brazilian law and Mercosul regulations, and the regulations of the European Union. Monitoring of heavy metal in food, like coffee, teas, and cocoa, provides useful information on safety features of food in regulatory procedures in terms of suitability of food for consumption, as well as its nutritional value.