Groundwater is an important resource that serves as a backbone of human development. In several regions, mostly in developing countries, groundwater from sedimentary and hard rock aquifers used for drinking is naturally contaminated with arsenic. In different countries in Asia such as India, Bangladesh, Cambodia, China, Nepal, Pakistan, Taiwan, Thailand and Vietnam, the situation of arsenic toxicity is alarming and severe health problems are reported amongst the inhabitants relying on groundwater as sources of water for drinking purposes