A simple, rapid and sensitive method is described for determination of arsenic in blood and urine of a poisoned patient at the level of µg/l based on differential pulse cathodic stripping voltammetry. Only arsenic (III) is deposited on mercury electrode in the presence of copper and selenium in hydrochloric acid medium. The total arsenic is performed by reducing As (V) to As (III) using sodium metabisulphite/sodium thiosulphate reagent stabilized with ascorbic acid. The As (III) concentration in blood and urine were found to be 9µg/l and 841µg/l respectively after about   twenty five days of homicidal poisoning through food and treatment as outpatient in hospital.

Keywords: Arsenic; Differential Pulse Cathodic stripping Voltammetry; Microwave Digestion System;               Homicidal Poisoning.