INTRODUCTION Tubewells have been used in Bangladesh since the 1940s. During the early days, the vast majority of rural people collected their drinking-water from surface-water sources, such as ponds and rivers. As the water from these sources was not bacteriologically safe, a large number of children and adults died each year from waterborne diseases. Consequently, with the aim of providing safe water to the vast population of Bangladesh, tubewells were installed. About 10 million tubewells (hand-pumps) had been sunk until recently in Bangladesh, which provided 97% of its population with access to safe water. Unfortunately, the identification of arsenic in tubewell water in 1993 gave rise to a new dilemma. Since the initial detection of arsenic contamination in groundwater in Bangladesh, it has rapidly emerged as a major public-health problem. Arsenic contamination in tubewell water has become evident in 61 of the 64 districts of the country. The Bangladesh Arsenic Mitigation and Water Supply Project (BAMWSP) has so far screened tubewells in 271 of 490 upazillas (sub-districts). Of 4,946,933 tubewells, located in 57,482 villages of these upazillas, 29.2% were arsenic-contaminated (0.05 mg/L). And in 8,540 villages, more than 80% of the tubewells were arsenic-contaminated. Moreover, 38,118 patients with arsenicosis were detected in 255 upazillas. The situation so far uncovered is considered as the tip of the iceberg, and with the passage of time, the size of the population exposed, the number of patients detected, and the complications of arsenic exposure continue to evolve (1-4).
