ABSTRACT

ABSTRACT: Arsenic (As) in shallow wells is a well-documented risk to the population in the large river deltas in Bangladesh and India (West Bengal). The expected health effects can be minimized by a number of mitigating phenomena in spite of the apparent high As intake. Some of these mechanisms are: i) presence of naturally occurring iron in raw water reduce the As concentrations in consumed drinking water. Individual behaviour may also inadvertently limit the As intake; ii) relatively short exposure time not allowing full effects to appear. Most As contaminated wells are no more than 10-15 years old; iii) higher than average dietary intake of phosphates (and other constituents) in food may compete with arsenate and prevent damages. Aeration of the raw water will remove iron and As. Cheap mitigation may be attained adding extra ferrous iron before aeration. This easy alternative to waiting for unaffordable mitigation measures reaching too few, requires building public awareness.