Herein the present study focuses on arsenic (As) contamination in groundwater, which plagues a vast section of the population of the world. Even the conservative estimates by the World Health Organization (WHO) estimate the number of people plagued by arsenic contaminated drinking water to be around 140-200 million. The Ganga- Brahmaputra fluvial plains in India and Padma-Meghna fluvial plains in Bangladesh are said to be one of the worst groundwater calamities to the humans. The Arsenic levels in drinking water in some of the most populated states in India are disproportionately higher than those defined by WHO guidelines. The paper, thus, delves into the anomaly in permissible limits defined by WHO and regional governments and its consequential effects. It briefly analyses the major sources of Arsenic contamination and its health effects in India. The study also looks closely into the states and districts plagued by the As contamination and explores the prominent treatment methods employed in as removal from the drinking water. Keywords: Arsenic, Adsorption, Geogenic, Arsenopyrite, Oxidation treatment