Arsenic contamination of groundwater is a form of groundwater pollution which is often 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 wells for water supply in the Ganges Delta, causing serious arsenic poisoning to large numbers of people. A 2007 study found that over 137 million people in more than 70 countries are probably affected by arsenic poisoning of drinking water. The problem became a serious health concern after mass poisoning of water in Bangladesh.[1] Arsenic contamination of ground water is found in many countries throughout the world, including the US.[2]
The World Health Organization recommends limiting arsenic concentrations in water to 10 μg/L, although this is often an unattainable goal for many problem areas due to the difficult nature of removing arsenic from water sources.[3]
Approximately 20 major incidents of groundwater arsenic contamination have been reported.[4] Of these, four major incidents occurred in Asia—in Bangladesh; West Bengal, India; Inner Mongolia, China; and Taiwan.[5] Locations of potentially hazardous wells have been mapped in China.[6]