Arsenic test is performed on a sample of random urine to measure level of Arsenic in the sample.It is performed to substantiate Arsenic Poisoning and also throughout treatment and once treatment of Arsenic Poisoning is over. Arsenic is present in a number of different forms; organic forms are nontoxic in nature while inorganic forms are toxic in nature. As arsenic is excreted mainly by glomerular filtration, test for arsenic in urine is the most effective screening test to measure arsenic exposure.