Assessment of heavy metals concentration in selected foods sold in markets within port-Harcourt city, Nigeria

Abstract

Heavy metals are toxic environmental substances which may bioaccumulate up a food chain and pose threat to the health of humans. The present study investigated the concentrations of heavy metals (Zn, Fe, Cu, Pb, Cd) in selected foods (wheat, millet, millet pap, maize, maize pap, groundnut, kuli-kuli and ose-oji) purchased from three different markets in Port Harcourt, Nigeria using Atomic Absorption spectrophotometry (AAS). The results indicate that the concentration of the heavy metals (mg/Kg) varied across the various samples: Zn (4.68±0.07-45.73±0.04), Fe (n.d-145.19±0.17), Cu (4.54±0.05-9.55±0.03), Pb (3.96±0.04-15.68±0.08), Cd (0.0156±0.01-0.2688±0.05). With the exception of Cd and Pb, other heavy metals studied were within acceptable limits. The levels of heavy metals in the pap samples (millet and maize pap) were of concern because these are popular weaning foods in Nigeria hence these metals could pose threat to the health of infants. Kuli-Kuli and ose-oji are also samples of interest because of their wide consumption and elevated levels of metals (Zn and Pb). There should be adequate monitoring of heavy metal content of these food sources to prevent incidence of heavy metal toxicity which may result from bioaccumulation with continued consumption of these food by the public.