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Concentrations of selected metals (Cu, Cd, Ni, Pb, Mn, Fe, Zn, Cr and Co) in some ready-to-eat-foods consumed in Nigeria were investigated with a view providing information on the risk associated with the consumption of these products. The concentrations of metals (mg.kg-1) in these ready-to-eat-foods are in the ranges of 2.4 – 5.2 for Cu; 0.1– 0.8 for Cd; 0.7 – 4.0 for Ni; 8.1 – 53.7 for Fe; 8.9 – 20.0 for Zn; 0.1 – 3.8 for Pb; 5.1 – 14.4 for Mn; 0.83 – 21.4 for Cr and 0.20 – 1.32 for Co. The concentrations and estimated intakes of Cd, Ni and Pb in some of these food types exceeded the permissible limits and tolerable daily intake respectively. The target hazard quotients (THQ) for the individual metals indicate levels of concern for Ni, Cd, and Co in some of the ready-to-eat-foods. The combined THQ values for the metals in the examined samples ranged from 1.7 to 10 with significant contributions from Cd, Ni and Co.

The concentrations, contamination/pollution index, anthropogenic input and enrichment factors for metals in soil in the vicinity of cassava processing mills in sub-urban areas of Delta State of Nigeria were examined. The concentrations of metals in all sites and depths ranged from 0.1 to 383.2 mg kg -1 for Mn, 4.0 to 11.3 mg kg -1 for Ni, 1746.4 to 2839.6 mg kg -1 for Fe, 0.01 to 3.70 mg kg -1 for Cr, 3.7 to 29.5 mg kg -1 for Cu, 21.9 to 97.3 mg kg -1 for Zn, 0.01 to 1.60 mg kg -1 for Cd and <0.01 to <0.01 mg kg -1 for Pb. The concentrations of metals at these sites were below the Department of Petroleum Resources target values for metals in soils except for Cd in some sites. A significant fraction of these metals aroses from anthropogenic sources. The percent anthropogenic fraction of metals in the soil follow the order Cd > Zn > Ni > Cu > Fe > Cr > Pb.

Samples of some popular brands of canned sardines in soybean oil in the Nigerian market were analyzed for levels of cadmium, lead, iron, cobalt, nickel, manganese, chromium, copper and zinc after wet digestion with acids by graphite furnace atomic absorption spectrophotometry. The mean concentrations for the metals in the different brands were as follows: cadmium 0.11-0.26 lg/g, iron 8.04-48.18 lg/g, cobalt 0.01-7.23 lg/g, nickel 0.04-3.26 lg/g, manganese 0.64-1.37 lg/g, chromium 0.01-0.10 lg/g, copper 0.10 lg/g and zinc 0.09-4.63 lg/g. Significant differences were observed in the heavy metal levels in the different brands of canned sardines except for copper and chromium. Cadmium, nickel and lead exceeded statutory safe limits.