Abstract

Levels of seven heavy metals (Fe, Pb, Zn, Cu, Ni, Cr and Cd) in muscles, gill, kidney, liver and tissues of some commercial fish species caught between August 2005 – September 2007 from Warri River, Niger Delta, Nigeria were assessed. Analysis was carried out using Flame Atomic absorption spectrometry for the heavy metal analysis of the different tissues. Concentration levels of Fe and Zn in the different tissues of the fishes were higher in most cases. Apart from Cu, the level of heavy metals in the different tissues of the fish species exceeded the maximum permissible limit specified by statutory authorities such Food and Agricultural Organization/World Health Organization, Median International Standard and European Union for food fish consumed by human. The order of heavy metals are Fe>Zn>Pb>Ni>Cr>Cu>Cd in gills and Fe>Zn>Pb>Ni>Cu>Cr>Cd in kidneys, livers and muscles. The concentration of the heavy metals in the different tissues were in the order; liver> kidney>gill>muscle. The concentrations of all the heavy metals in each of the tissues were statistically different (P<0.05) among the different fish species. Hence consumption of fish from the Warri River poses a health risk to the consumers due to accumulation of high levels of Pb, Cd, Fe, Cr, Ni and Zn in fish through biotransfer of metals especially through water phase. Bioaccumulation of metals by humans has the potency to cause diverse ailments such as insomnia, brain damage and cancer. We, therefore, recommended that industrial and domestic effluent discharged into the Warri River be treated, controlled and monitored



Comments


Must Read