Trace Heavy Metal Levels of Some Bouillon Cubes, and Food Condiments Readily Consumed in Nigeria

Abstract

The Fe, Zn, Pb and Cd contents of bouillon cubes and other food condiments readily consumed in Nigeria were determined by atomic absorption spectrometry after acid digestion with 2:1 HNO ₃ /HClO ₄ .The level of Pb in the samples were generally low and below detection limit (<0.02µg/g).The levels of the other metals ranged from 3.60-3.65µgCd/g, 3.65-8.95µgFe/g, and 1.60-4.40µgZn/g for bouillon cubes; 3.90-5.05µgCd/g,11.05-32.70µgFe/g,and 3.0-3.70µgZn/g for chicken seasonings; ND-1.80µgCd/g, 32.35-320.85µgFe/g, and 13.65-90.0µgZn/g for curry powders; 0.85-4.80µgCd/g, 32.70-73.20µgFe/g and 3.70-21.25µgZn/g for beef seasonings; 1.10-1.15µgCd/g, 92.35-419.05µgFe/g, and 25.95-48.10µgZn/g for thyme; and 0.80-4.90µgCd/g, ND-50.60µgFe/g and 3.4-22.55µgZn/g in mixed spices. Zn levels correlated strongly (R ² = 0.77) with Fe levels in the samples. The low level of the toxic metals, Pb and Cd, indicates that these products meet the safe limits specified by most food standards. The frequency and regularity of consumption and popularity of these products demands periodic surveillance to avoid contamination. This result will complement available data on food composition in Nigeria.