21
Aug
10

Groundwater, arsenic and irrigation

Tube well irrigation in West Bengal and Bangladesh is very common. Nearly 9,00,000 tube wells n Bangladesh and 5,50,000 in West Bengal constantly pump groundwater to irrigate rice fields. The groundwater contains greater than 3.2 mg/L of arsenic. In Bangladesh nearly 2 million ha of land is irrigated using arsenic rich groundwater while a little less than 2 million ha land is under irrigation through arsenic contaminated groundwater in West Bengal. Estimates by FAO indicates that 1 million kg of arsenic is added to arable soil every year in these regions. From groundwater, arsenic now has entered the food chain and both As (III) and As (V) is found to enter the rice plant and other vegetable by different mechanism. Thus an arsenic – path – chain, from water to food through soil  has been established. A large number of scientific reports have documented these facts and a great debate is on at several international conferences on the fate of human race due to this menace. In fact more recent studies indicate that the entire Gangetic drainage basin is affected arsenic problem. What is not clear is  1) the fate of arsenic that enters the animals through fodder, 2) crop growth and yield, 3) mechanism of up-take of arsenic by plants 4) genetic effect on humans and animals. This opens up a chain of problems that need to be addressed by the future scientists. Now it is clear that this problems has to be tackled, not by a single group, but by a multi disciplinary group consists of geologists, biologists and  physicians.

 Mind set and will to change is what is needed to tackle this problem failing which generations may get affected in future……..read the article posted in Down to Earth in 2006!!

Arsenic 3 Nov 06_Down to Earth