Revista de química analítica ambiental

Evaluation of Effects of Heavy Metal Contents of Some Common Spices Available in Odo-Ori Market, Iwo, Nigeria

Abstract

Peter Olusakin O and David Olaoluwa J

This study is aimed at assessing the levels of Fe, Cu, Cd, and Pb in some common spices available in Odo-ori Market, Iwo, Osun State, Nigeria. Four samples each of naturalspices (ginger, garlic, onion and locust beans) and processed spices (curry, thyme, nutmeg and beef spicy) were bought and analysed for Fe, Cu, Cd, and Pb using Atomic Absorption Spectrophotometry. 2 g of each of the samples was digested using 30 mL of concentrated HNO3 and heated until digestion was complete. The digests were filtered into standard 30 mL volumetric flask using Whatmann filter paper and made up to mark with distilled water. The digested samples were analysed for Fe, Cu, Cd, and Pb using Buck Scientific Model 210 VGP Atomic Absorption Spectrophotometer. Results showed that the concentrations of heavy metals, such as Fe, was present at level ranging from 33.4 mg/kg – 107 mg/kg and Cu, was present at level ranging from 4.35 mg/kg - 8.40 mg/kg in natural spices. Cd was above the permissible limit set by WHO (0.30 mg/kg). The Fe and Cu levels in natural spices were below maximum permissible limit set by WHO while Cd was above the permissible limit. Therefore, it can be concluded that majority of these spices were not contaminated with the studied heavy metals except Cd which was present in natural and processed spices above MPL and indicating Cd pollution in the natural and processed spices. To avoid chronic effect (which involved accumulation of the metals in the body system and which can be harmful to human health), too much of the spices (processed) and continuing/routine use should be avoided.