The Arsenic Drinking Water Crisis in Bangladesh
Domestic Water Supply
Published Online: 15 JUL 2005
Copyright © 2005 by John Wiley & Sons, Inc.
How to Cite
Bryce, C. and Philp, J. 2005. The Arsenic Drinking Water Crisis in Bangladesh. Water Encyclopedia. 1:1–3.
- Published Online: 15 JUL 2005
Although the incidence of arsenic poisoning in groundwater is worldwide and includes Bangladesh and India, Taiwan, Vietnam, Chile, China, North America, and Finland, the area of the highest demand for a resolution of the problem is Bangladesh. The source seems to be geological, for arsenic has been found in tube well water used for drinking and irrigation, although the geochemistry is not completely understood. As many thousands of boreholes have been produced to support modern irrigation systems, the underground aquifers are aerated, which causes transformation of anaerobic conditions to aerobic conditions. The presence of oxygen in this way decomposes arsenopyrite-releasing arsenic acid. At low pH, this arsenic dissolves in water and hence leads to water contamination. The arsenic content of sediments is high relative to crustal concentrations. The biogeochemical cycling of arsenic and iron are coupled in deltaic systems; iron oxyhydroxides act as a carrier for the deposition of arsenic in sediments. From there, it can be mobilized by bicarbonate, which can extract arsenic from sediments under both aerobic and anaerobic conditions.
Arsenic also becomes a pollutant as a result of various industrial uses and activities. Arsenic is a metalloid, and its primary usage has been in agriculture, in formulating herbicides, especially for controlling weeds in cotton fields. Sodium arsenite has been used as an insecticidal ingredient in sheep-dips. In industry, arsenic has found use in glass manufacture and a new role in the semiconductor industry. Copper smelting releases significant amounts into soils.
- health effects;
- water treatment