Determination of some heavy metal content in tilapia and cat fish species in Lake Njuwa, Adamawa State, Nigeria

Abstract

Concentration (mg/kg) of Lead (Pb), Chromium (Cr), Copper (Cu), Nickel (Ni) and Cadmium (Cd) were measured in various organs (such as gills, bones and muscles) of Tilapia and Catfish collected from Lake Njuwa Adamawa state during dry season (February, 2017) and wet season (August, 2017). The results obtained were compared to permissible limits set by World Health Organization, WHO (1985), Food and Agricultural organization, FOA (2003), to ascertain its health implications. Comparison between the heavy metals concentration of dry and wet season were carried out using Mann Whitney u test, the relationship between the heavy metal concentration and the weight of the fish was carried out using Pearson correlation test. All the analysis were determined at significant level of p>0.05 using Microsoft excel 2010 and statistical package for social science (SPSS) 2.3. The results obtained shows that the heavy metals are more concentrated in the bones (2.30, 2.50, 1.37, and 1.40) than the gills (2.17, 2.20, 1.19 and 1.23) and the muscles (0.5, 0.7, 0.99 and 1.03) of both the Tilapia and Catfish during the wet season than the dry season.

Keywords: Heavy metal, Tilapia fish, Catfish, Lake, dry season, wet season