Mohd Sham Othman

1. Introduction The toxicity, persistence and accumulation of heavy metal pollution in the ecosystems have made it a critical environmental problem. The elements that are found naturally and with a high atomic weight and density more than 5 g/cm3 can be recognized as heavy metals and are differentiated by the rest of the metallic elements in their chemical and biological behavior [1].

1. Introduction Heavy metal contamination of rivers teaming with aquatic life is a global issue. Among these heavy metals, cadmium is considered to be one of the most toxic heavy metals [1]. Cadmium is a nonessential heavy metal which exists in the environment in very small concentrations and often as impurities in non-ferrous metals like zinc, lead and copper [2].

1. Introduction Heavy metal contamination of rivers teaming with aquatic life is a global issue. Among these heavy metals, cadmium is one of the most toxic heavy metals [1] . Cadmium is a nonessential heavy metal that exists in the environment in very small concentrations and often as impurities in non-ferrous metals like zinc, lead, and copper [2] .