Kharagpur - Arsenic contamination of groundwater is a form of groundwater pollution which is caused due to naturally occurring high concentrations of arsenic in deeper levels of groundwater. It is a high-profile problem due to the use of deep tube well for water supply in the Ganges delta, causing serious arsenic pollution to large numbers of people.

A group of scientist from the highly reputed Indian Institute of Technology, Kharagpur (IIT KGP) have discovered this particular strain of arsenic reducing bacteria. The strain is named as Rhibozium bacteria and the entire project was under the guidance Prof. Pinaki Sar. Excess arsenic is known to reduce the formation of root nodules in legumes, currently, little is known about how the legume–rhizobium symbiosis is affected by high arsenic concentrations. Arsenic contaminated water typically contains arsenous acid and arsenic acid or their derivatives.

Their names as "acids" is a formality, these species are not aggressive acids but are merely the soluble forms of arsenic near neutral pH. These compounds are extracted from the underlying rocks that surround the aquifer. Arsenic acid tends to exist as the ions [HAsO4]2− and [H2AsO4] in neutral water, whereas arsenous acid is not ionized. Prof Pinaki Sar along with his team mates collected groundwater sample and checked for arsenic content using arsenic quantification methods. It is known arsenic is found in two ionic forms namely as3+ and as5+. The bacterial strain of Rhizobium is capable of producing a protein namely arsenic reductase which reduces as5+ to as3+ which is non-toxic in nature and does not form arsenous acids thus rendering the arsenic ineffective.

This discovery does show a new path in eradication of Arsenic related problems in India. More than 3 million people are affected by arsenic contamination in India. We wish this discovery reaches newer heights and saves many lives which are at stake!