An alarmingly large population of Developing World specially India and Bangladesh is exposed to arsenic poisoning due to continuous usage of arsenic-contaminated ground water. Experts believe this to be the greatest case of mass poisoning in the history of the world. The domestic and international response to address this crisis, unfortunately, has been slow and somewhat discouraging. Even though handling the arsenic crisis is an enormous task, it nevertheless, needs to be addressed. Arsenic contamination of groundwater specially in Bangladesh, India, Nepal and Pakistan has mainly occurred due to natural reasons. As per the most plausible theory, in the Late Pleistocene – Recent times, iron and arsenic-bearing sulphidic minerals in upper reaches of the Ganges river belt may have undergone oxidation due to exposure to atmosphere during erosion, resulting in subsequent mobilization of arsenic and iron downstream.

Besides, the same problem, but to a lesser extent, has been observed in other parts of the world as well, such as China, Taiwan, Inner Mangolia, Obuasi Ghana, Corodoba Argentina, Antofagasta, Chile Lagunera Mexico, Cornwall Britain and more recently in United States.

Considering the rate at which this poison is spreading its web to the most interior parts all over the world, there is an urgent need to develop ways to mitigate this problem by reducing the level of arsenic in drinking water to tolerable limits through easy and inexpensive means.

There has been considerable advancement in water treatment technologies worldwide since the discovery of the arsenic contamination in West Bengal, India, Bangladesh and elsewhere. This review then looks at remedial measures with special emphasis on cost and feasibility for third world nations such as India, Bangladesh , Nepal and Pakistan to provide arsenic free water . This paper also examines use of other alternative water resource such as surface water and rainwater harvesting for the third world nations to aid policy makers and managers who may oversee and advise long-term solutions for this acute poisoning of ground water