In large parts of Eastern India, the groundwater is contaminated by:

Water pollution is one of the most serious environmental problems. It occurs when water is contaminated by such substances as human and animal wastes, toxic industrial chemicals, agricultural residues, oil, and heat. One of the cause of water pollutions is groundwater contamination which poses a serious risk to human health.

Groundwater Contamination:

• It is caused by the introduction of chemicals to the ground all the way down into groundwater.
• Arsenic is a toxic element that has no apparent beneficial health effects for humans. Most waters in the world have natural arsenic concentrations of less than 0.01 mg/liter. It is introduced into soil and groundwater during weathering of rocks and minerals followed by subsequent leaching and runoff.

• The groundwater of Eastern part of India is Arenic (As) contaminated, seven states namely, West Bengal, Jharkhand, Bihar, Uttar Pradesh in the flood plain of the Ganga River, Assam and Manipur in the flood plain of the Brahmaputra and Imphal rivers and Rajnandgaon village in Chhattisgarh state have been reportedly affected by Arsenic contamination in groundwater above the permissible limit of 10 µg/L.
• Arsenic groundwater contamination has far-reaching consequences including its ingestion through food chain. Arsenic poisoning leads to potentially fatal diseases like skin and internal cancers.