Variability of Heavy Metals in Wild Catfish Clarias gariepinus Collected South and North Cairo Area. II. Essential Heavy Metals.

Four surveys were undertaken to investigate the bioaccumulation of Fe, Cu, Zn and Mn in the liver, kidney, gills, skin and muscles of Clarias gariepinus from the River Nile south (Al-Aiat) and north (Barrage) areas of Cairo. Metals bioaccumulation were analyzed then applied to differentiate between the concentrations found at the two locations, between all of the surveys, and the two sexes. No significant seasonal variations detected in the water metals. Fe and Cu are the highest elements and Mn is the least element. Cu is the more element affected by the locality with higher concentrations in Al-Aiat than Barrage. No hazardous effect on the environmental ecosystem observed. Higher concentrations of metals were observed in the tissues of C. gariepinus than the water in which they live. All heavy metals in all organs are present in measurable quantities and still within the safe limits for consumption. Concentrations of the analyzed metals revealed large numbers of significant values concerning location, sex and season differences. Discussion is focused on the significant results.