RESEARCH SHOWS BACTERIA PART OF ASIAN ARSENIC ILLS
 July 6, 2004

Bacteria are partly to blame for mass poisonings in Bangladesh and India, scientists have found.

Millions of people drink arsenic-laden water drawn from the region's deep wells, originally drilled to provide clean water. But the well-intentioned wells turned out to tap a hidden source of arsenic, deep within the sediments.

In last week's Nature, researchers from England and India describe the role metal-munching bacteria play in transferring arsenic from the soil into the water.

Adding the chemical acetate provided extra electrons for the bacteria to grab onto, thus releasing arsenic, the scientists found. They warn that regional officials should avoid doing anything - such as irrigation pumping - that could deliver more electrons into the mix and thus make the arsenic poisoning worse.