Some 65 of the known 92 elements are metallic in nature. the term 'metal' designates an element that is a good conductor of electricity whose electical resistance is directly proportion to absolute Ot. In additional, metals share some distinctive characterstics such as high thermal conductivity and high density. Metallic elements are intrinsic components of the environment. Some threat to living as well as non-living world, and so man is no exception.
