Speciation of Lead, Iron and Cadmium in Selected Brands of Canned Sardine Fish Sold in Port Harcourt, Rivers State, Nigeria

Abstract

Chemical Speciation is a significant factor that governs toxicity and mobility of heavy metals Therefore knowledge of polar and non-polar forms of metals could be useful in predicting toxicity. In this research chemical species of lead, iron and cadmium in selected canned fish marketed in Nigeria were evaluated as polar form of nonpolar concentrations. Dry digestion was carried out on the sardine fish meal while wet digestion was applied to the fish oil. The metal concentration was determined using the Flame Absorption Spectrophotometer. The results show that the concentration of the trace metals in the fish meal and fish oil ranged from 13.12 ± 3.81 (Pb), 19.22 ± 4.83 (Fe), 2.50 ± 0.48 (Cd) mg/kg and 14.37 ± 4.34 (Pb), 15.54 ± 2.45 (Fe), 1.65 ± 0.4 (Cd) mg/kg respectively. Chemical speciation of fish meal and fish oil gave rise to varying amounts of polar and non-polar fractions. The polar fractions of fish meal and fish oil ranged between 0.82 ± 0.49 (Pb), 2.0 ± 0.48 (Fe), 0.27 ± 0.17 (Cd) mg/kg and 4.13 ± 1.47 (Pb), 5.93 ± 1.25 (Fe), 0.50 ± 0.17 (Cd) mg/kg respectively; non polar fractions of fish meal and oil ranged between 2.07 ± 0.73 (Pb), 2.23 ± 0.58 (Fe), 0.36 ± 0.08 (Cd) mg/kg and 10.13 ± 2.94 (Pb), 8.65 ± 1.63 (Fe), 1.45 ± 1.41 (Cd) mg/kg respectively. Results reveal that the non-polar species of metals were predominant in the canned fish analyzed.