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Emergency Relief for the Bangladesh’s Arsenic Disaster

Source of Arsenic

The arsenic probably originates in the Himalayan headwaters of the Ganges and Brahmaputra rivers, and has lain undisturbed beneath the surface of the region’s deltas for thousands of years in thick layers of fine alluvial mud smeared across the area by the rivers.

According to David Kinniburgh of the British Geological Survey, who has recently completed a detailed study of the arsenic’s route into millions of tube wells, the arsenic concentration in the mud is not extraordinary. Time is the culprit. The mud in Bangladesh lies thicker, wider and flatter than almost anywhere on Earth. It can take hundreds or thousands of years for underground water to percolate through the mud before reaching the sea. All the while it is absorbing arsenic.

This, says Kinniburgh, helps explain the diverse pattern of arsenic concentrations in tube well waters. The contaminated wells almost all take water from a depth of 20 to 100 metres. Shallower wells are clean because they contain mostly recent rainwater or water flowing swiftly through the sediments. Deeper wells tap water in older sediments, which have by now been flushed clean of arsenic. It will take thousands of years, says Kinniburgh, before the rest of the arsenic will wash away into the Indian Ocean.

Many underground water sources around the world contain arsenic. Parts of Taiwan, Argentina, Chile and China have all suffered epidemics of skin diseases, gangrene and cancer as a result. Smith’s analysis of the Taiwan epidemic in particular helped set the WHO arsenic standards for water and is the basis for his current predictions. Bangladesh, he says, is quite unprecedented.

UNICEF Explanation

UNICEF explains today that “at the time, standard procedures for testing the safety of groundwater did not include tests for arsenic [which] had never before been found in the kind of geological formations that exist in Bangladesh.” But many geochemists, such as John McArthur at University College London, scoff at such a suggestion. They blame dogma among public health people with no knowledge of geology, and who equated underground water with safe water.

World Bank Approach

The World Bank announced an emergency three-year program to identify the killer tube wells using simple tests and to “put in motion concrete actions [to] combat a major health crisis with devastating effects on the lives of millions.” With almost every one of the country’s 68,000 villages potentially at risk, the Bank said it would initially survey 4,000 villages and draw up action plans for each. This “fast-track project” was to be the first phase in a 15-year program to screen the country’s tube wells.

Project Stalled

Richard Wilson, a leading analyst of the crisis from Harvard University’s department of public health, says, “The project is stalled.” He blames the Bangladeshi government’s failure to “decide how to spend the money” and says that leading officers at the Bank are privately “most upset about it.”

Task too Big for NGO

But the task is far too big for any NGO. Shahida Azfar, UNICEF’s representative in Dhaka, told a conference in the city last May that “to date, only 250,000 tube wells have been tested. If we keep this up it will take us 30 years to complete the testing.”

No Proven Method

And few if any action plans have been completed because, says Minnatullah, scientists have failed to find a “proven, affordable” method of removing arsenic from village pumps.

Where is Situation the Worst?

Where is the situation worst? Chakraborti says “one of the worst villages I have ever visited” is Stadium Para in Meherpur district, right on the border with India. Here nine residents have already died of cancerous ulcers caused by arsenic. One was only 25 years old. But, after five years of surveying, he nominates the southeastern village of Seladi as “in all probability the most arsenic-contaminated village in the world.” Here 72 out of 73 tube wells are contaminated. No fewer than 21 contain arsenic at more than 1,000 parts per billion, and the highest at 4,000 ppb, or four hundred times the WHO limit.

Lack of Education a Problem

There are some technical solutions to providing safe drinking water for the people of Bangladesh–albeit hard to execute in such a poor, ill-educated and rural countryside (see box). But first the millions of dangerous tube wells have to be identified. The slow progress of the World Bank program so far could prove a mortal blow. In his September report, Smith warned that “the worst thing that can possibly be done is nothing.” But for most Bangladeshis caught up in this disaster, nothing is exactly what is being done.

What Next?

In the first step of the mammoth task of testing the country’s tube wells, volunteers, aid workers and officials paint the dangerous ones red, which should only be used for washing. The villagers are supposed to use the safe wells exclusively for drinking, but that’s not easy when the lucky one is found in someone else’s backyard.

In the longer run, part of the answer lies in sinking deeper wells to tap cleaner water. But it will take millions of dollars to install these wells in addition to the needed surface tanks and distribution pipes. Also some deep tube wells in West Bengal have started bringing up arsenic months or years after they were opened.

Another idea is to adopt traditional methods such as ponds and tanks to “harvest” rainwater. This will work in some places, says Shahida Azfar from UNICEF, but “there is not enough rain all year for that to be feasible as the main strategy.”

Could the tube well waters be treated? While a large number of ideas for filters and chemical treatments have been tried out in the past two years, there is “no proven affordable arsenic removal technology available yet,” according to Khawaja Minnatullah of the World Bank. Most experts warn against blanket solutions. Each village needs its own plan. And none of them can begin planning until it knows which of its tube wells are pouring poison into villagers’ buckets.

Potable Water Should Be
Available to Those in Need


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