ABSTRACT
Noted by their high electrical conductivity, malleability, and luster, as well as their tendency to voluntarily lose electrons to form cations, metals are divided into light and heavy categories according to their specific densities. The concept of heavy metals appears to vary from field to field. Metallurgy defines heavy metals by their specific density, physics does so by atomic number, chemistry studies their chemical behavior, and astronomy considers any element heavier than hydrogen and helium as a heavy element. Compared to light metals, heavy metals rarely occur in the tissue structures and metabolic products and bring limited benefits to living organisms. Treatment options for heavy metal poisoning include removal of exposure source, gastrointestinal decontamination, and chelation therapy. Since heavy metals are ubiquitously distributed in the environment, improved education about their toxicity and approaches to avoid their taking-up are crucial to reducing the incidence of heavy metal poisoning in the human population.
