Arsenic Problem
1 Introduction:
Arsenic is a ruthless killer in Bangladesh's drinking water is making millions of people sick and may be causing as many as 3,000 deaths each year. That killer--naturally occurring arsenic in the water drawn from family wells--appears to have been released through a process involving crop irrigation, at least in one part of the country.
At a research site in the southern part of Bangladesh, scientists calculated that irrigation pumping, which began in the last several decades, has dramatically altered groundwater flow through the aquifer. They show that the resulting changes to the chemistry of the groundwater have the potential to either increase or decrease arsenic levels, in a paper written by an MIT-led team of scientists in the Nov. 22 issue of Science.
Arsenic poisoning, usually characterized by sores on the chest, or blackened knotty palms, and cases of skin, lung, liver, bladder and pancreas cancers have been linked to arsenic in the drinking water. In 1998 the World Bank agreed to provide Bangladesh a $32.4 million credit to develop a method of controlling the arsenic. But today, most Bangladeshis continue to drink arsenic-laced water. The World Bank describes the problem as one of the world's primary environmental challenges. The World Health Organization refers to it as "the largest mass poisoning of a population in history" in a fact sheet published in March.
The mass poisoning began, sadly enough, with a well-meaning attempt to provide clean drinking water for Bangladeshis, who suffered from cholera and other diseases caused by bacteria in water taken from surface reservoirs. To remedy that problem, the Bangladesh government, with the help of international aid organizations, drilled between 6 and 10 million wells at depths ranging from 50 to 300 feet to provide clean, safe water for individual households.
At about the same time, farmers in this largely rural country began irrigating land so that rice, the country's main food staple,
Arsenic is a ruthless killer in Bangladesh's drinking water is making millions of people sick and may be causing as many as 3,000 deaths each year. That killer--naturally occurring arsenic in the water drawn from family wells--appears to have been released through a process involving crop irrigation, at least in one part of the country.
At a research site in the southern part of Bangladesh, scientists calculated that irrigation pumping, which began in the last several decades, has dramatically altered groundwater flow through the aquifer. They show that the resulting changes to the chemistry of the groundwater have the potential to either increase or decrease arsenic levels, in a paper written by an MIT-led team of scientists in the Nov. 22 issue of Science.
Arsenic poisoning, usually characterized by sores on the chest, or blackened knotty palms, and cases of skin, lung, liver, bladder and pancreas cancers have been linked to arsenic in the drinking water. In 1998 the World Bank agreed to provide Bangladesh a $32.4 million credit to develop a method of controlling the arsenic. But today, most Bangladeshis continue to drink arsenic-laced water. The World Bank describes the problem as one of the world's primary environmental challenges. The World Health Organization refers to it as "the largest mass poisoning of a population in history" in a fact sheet published in March.
The mass poisoning began, sadly enough, with a well-meaning attempt to provide clean drinking water for Bangladeshis, who suffered from cholera and other diseases caused by bacteria in water taken from surface reservoirs. To remedy that problem, the Bangladesh government, with the help of international aid organizations, drilled between 6 and 10 million wells at depths ranging from 50 to 300 feet to provide clean, safe water for individual households.
At about the same time, farmers in this largely rural country began irrigating land so that rice, the country's main food staple,