Quantifying the Spread of Arsenic Contamination in Groundwater of the Brahmaputra Floodplains, Assam, India: A Threat to Public Health of the Region

Arsenic contamination in groundwater in many countries, including India, has become an issue of global concern. After a relatively recent discovery of arsenic in the upper Brahmaputra floodplains, a Rapid Assessment Program for drinking water in Assam state of India covering all the districts was conducted. The study revealed presence of arsenic beyond permissible limit of 50 ppb in 72 blocks out of 192 blocks spread over 22 districts. A three phase analysis procedure adopted in this study yielded consistent results, showing good analytical performances for a large scale study. Of total 1726 samples spread across 18 districts, a major percentage of samples indicated concentration range of 60 to 150 ppb, emphasizing the need to take up intensive arsenic based research and to develop technologies and water management strategies to provide arsenic free drinking water in the region.