Possible cause of arsenic in water found

DHAKA, Bangladesh, Nov. 15 (UPI) -- Researchers at the Massachusetts Institute of Technology said they may have discovered what caused arsenic to appear in drinking water in Bangladesh.

Researchers at the U.S. school's Department of Civil and Environmental Engineering said in an MIT release Sunday the arsenic concentration found underground in Bangladesh may be due to the use of irrigated agriculture as well as the construction of villages with ponds.

Bangladesh began struggling with widespread arsenic poisoning after the country's residents began consuming groundwater instead of water from surface sources like ponds and rivers.

MIT researchers suggest the excavation of ponds in Bangladesh may serve as the source of the organic carbon that helps arsenic infiltrate groundwater after dissolving off soil and sediments.

"Our research shows that water from the ponds carries degradable organic carbon into the shallow aquifer. Groundwater flow, drawn by irrigation pumping, transports that pond water to the depth where dissolved arsenic concentrations are greatest and where it is then pumped up into the irrigation and drinking wells," said Charles Darvey, a civil and environmental engineering associate professor at MIT.