Groundwater Poisoning in Bangladesh
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The Discovery of Arsenic Contamination of Groundwater in Bangladesh
The supply of pure drinking water to at least 97 percent of the people of the country has been one of the few success stories in public health care in Bangladesh. The success, however, was compromised by reports of arsenic found in the groundwater from tubewells in many parts of the country. In the early 1990s, arsenic—the new menace—shattered the notion of tubewell water as “safe.”

Map of Bangladesh Showing the Regional Distribution of Arsenic in Groundwater

Arsenic as a public health problem was first identified in West Bengal, India, where the geological formations, economic conditions, food habits, and tubewells are similar to those in Bangladesh. In the early 1990s, people started to develop arsenicosis, the disease caused by arsenic, in the arsenic-affected zones of West Bengal. Facing a flood of cases in West Bengal, health workers started looking for similar problems in Bangladesh, and found that millions of people all over the country were being poisoned by drinking arsenic-laced water. Arsenic contamination in Bangladesh was first identified in 1993 by the Department of Public Health Engineering of the government of Bangladesh in the tubewell water in the Chapai Nawabganj district in the north-western part of the country.

The World Health Organization (WHO) guideline value (recommended limit) for arsenic in drinking water is 10 mg/L and the national standard in most countries, including Bangladesh, is 50 mg/L. With varying levels of contamination from region to region, the groundwater of sixty-one out of sixty-four districts in Bangladesh is contaminated with arsenic. According to a study conducted by the British Geological Survey and the Department of Public Health Engineering (DPHE) of Bangladesh, arsenic concentrations in the country ranged from less than 0.25 mg/L to more than 1600 mg/L. This study report estimates that out of the 1999 Bangladesh population of 125.5 million, up to 57 million are drinking water with an arsenic concentrations greater than the WHO guideline value and up to 35 million drinking water with concentrations in excess of the Bangladesh standard. The area containing the worst arsenic concentrations stretches across the south and east of Bangladesh. The capital city of Dhaka appears to be more or less safe from arsenic contamination (less than 0.5 mg/L arsenic).

Number of People Drinking Arsenic Contaminated Water in Bangladesh

35 million Number of people drinking arsenic contaminated water according to the Bangladesh standard of 50 mg/ L	57 Million Number of people drinking arsenic contaminated water according to the Bangladesh standard of 50 mg/ L

Arsenic Contamination of Drinking Water in Bangladesh
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This is the greatest case of poisoning in the history of mankind: In Bangladesh, the health of 35 to 80 million people is endangered due to water contaminated by arsenic. The problem was first detected in the early 1980s in the Indian state of Western Bengal, a neighbor of Bangladesh. It quickly became evident that this contamination also existed in Bangladesh. Another ten years would pass, however, before the authorities and the international community mobilized their efforts. The aim is simple: to make sure the people of Bangladesh have safe drinking water. Achieving it, however, is far more complex. There is no miracle solution in sight and, meanwhile, millions of people are slowly becoming poisoned.

Number of people drinking arsenic contaminated water according to the WHO Guideline value of 10 mg/ L

Sources of Arsenic: A Natural Origin?
It is now generally agreed that the arsenic contamination of groundwater in Bangladesh is of natural origin, deriving from the geological strata underlying Bangladesh. It is also suggested that this arsenic is transported by rivers from the sedimentary rocks in the Himalayas.