In 1974 Bangladesh had 71,000,000 people and was the world’s second most densely populated country. The infant mortality rate was 125 per 1,000 live births. The average annual income was equivalent to US $70 per capita. The life expectancy at birth was approximately 46 years. Many premature deaths resulted from drinking surface water contaminated with bacteria causing diarrhea, cholera, typhoid, and other life-threatening diseases (1).
Aid agencies, the Bangladesh government, and private individuals began installing 2,500,000 tubewells to prevent these deaths by providing access to microbially safe groundwater for drinking (2). By 1995 Bangladesh had 120,000,000 people (3), approximately 97% of Bangladeshis drank well water (2, 4), and the life expectancy at birth had increased to 55 years (3).
Regrettably, this new source of drinking water was not tested for toxic metals. In 1993 chronic arsenic poisoning attributed to groundwater ingestion was first diagnosed. By 1999 a total of 2,953 cases of chronic arsenic poisoning were identified in Bangladesh (5); however, most of this country remains unsurveyed and the actual number of cases is expected to be in the tens or hundreds of thousands (6). These diagnoses include melanosis, leukomelanosis, keratosis, hyperkeratosis, nonpitting edema, gangrene, and skin cancer (5). Over 50,000,000 Bangladeshis are drinking water with unsafe levels of arsenic.
This report summarizes our 1997 field program. The purposes of this field program were to determine the nature, extent, and treatment of arsenic-affected groundwater in Bangladesh. This was the first national-scale survey of arsenic-affected drinking water in Bangladesh.