Arsenic is widely distributed in the earth's crust. It is used in some pesticides and industrial applications. Organic forms of Arsenic are normally present in certain food types. Inorganic Arsenic is carcinogenic to humans. This assay helps in the diagnosis of Arsenic intoxication. Since blood concentrations of Arsenic are elevated only for a short time after exposure, hence urine Arsenic is the preferred method of screening for Arsenic exposure.