Levels of some trace metals (Pb, Cd and Ni) and their possible health risks from consumption of selected fish and shellfish from Nigerian markets

The study assessed the levels of Pb, Cd and Ni in fish and shellfish from Nigerian markets and also evaluated any possible risk in their consumption. The dried fish and shell fish samples were predigested with 1mL HNO3 and later ashed at 450oC. The ash was dissolved in 5 mL HCl and the solution was analysed with an atomic absorption spectrophotometer. Results show that mean metal concentrations (mg/kg) in fish were in the following ranges: Pb (3.48-8.93), Cd (0.23-0.68), and Ni (1.57-4.36) while in shell fish, the ranges were: Pb (4.05-6.35), Cd(0.43- 0.61) and Ni (2.37-3.69). There was evidence of considerable contamination as most of the samples had values exceeding the standard permissible limits set by some regulatory bodies. The estimated daily intake of lead for adult and children were appreciable. The total hazard indices (THI) were less than one showing low risk from consumption of the studied fish and shellfish species