Metal ions can be incorporated into food chains and concentrated in aquatic
organisms to a level that affects their physiological state. Of the effective pollutants are
the heavy metals which have drastic environmental impact on all organisms. Trace
metals such as Zn, Cu and Fe play a biochemical role in the life processes of all aquatic
plants and animals; therefore, they are essential in the aquatic environment in trace
amounts. In the Egyptian irrigation system, the main source of Cu and Pb are industrial
wastes as well as algaecides (for Cu), while that of Cd is the phosphatic fertilizers used
in crop farms (Mason, 2002).