Evaluation of Heavy Metals Concentration in Imported Frozen Fish Trachurus Murphyi Species Sold in Zaria Market, Nigeria

摘要

The aim of the study is to assess the quality of fish imported into Nigeria with samples collected in Zaria. Concentrations of cadmium, lead, mercury, iron and nickel (Cd, Pb, Hg, Fe and Ni) were determined in the tissues/organs (skin, muscles, gills, liver, intestine, kidneys, brain and bones) of Trachurus Murphyi fish species on the basis of their import batches and across two major fishing origins. Health risks to human via dietary intake of fish were determined by the assessments of hazard quotients (HQ), daily intake of metals (DIM) and the individual's health risk index (HRI). Elemental determinations of the metals were performed by AAS via microwave digestion method of the fish tissues. The analysis of heavy metals variations (Post-Hoc) shows there are no significant differences (p<0.05) across the batches of most tissues. However, significant correlations among the tissues for each of the heavy metals were observed. Investigated results indicate high concentrations of heavy metals exist in each tissue and were above the safety limits recommended by FAO/WHO. The levels of heavy metals across the entire tissues were given in an increasing order as: Fe > Hg > Pb > Cd > Ni. However, individuals consuming fish above the recommended daily intake might be at risk from ingestion of heavy metals at unacceptable concentrations.