CHAPTER ONE
INTRODUCTION
Heavy metals are any metals exposure to which is clinically undesirable and constitute a potential hazard. The presence of heavy metal in the aquatic environment is the major concern because of their toxicity of animal life, thus disturbing the natural ecological balance (Bhattachary et al., 2008). The occurrence of heavy metals in aquatic ecosystem in excess of natural. Load has becomes a wide spread problem and a matter concern individual life in an environment (Voegborlo et al, 1999). The sources of toxic heavy metals in aquatic environment could be traced to both natural and anthropogenic arising from anthropogenic activities have taken place in aquatic ecosystem affecting the aquatic habitat and fish, the major component of the food chin leading the human (Mason, 1996).
Heavy metals and organic compounds can bioaccumulate in chains. Heavy metals are conservative pollutants in that they are broken down over such a long time scale that they effectively becomes permanent addition to the aquatic environment (Mason, 1996).
Heavy metals in fresh water were found to occur through absorption across the gill surface or through the gat was well tract.