Hooked on arsenic

An unprecedented crisis of drinking water contaminated by natural arsenic affects nearly 100 million people in West Bengal and Bangladesh. Experts dealing with the toxicity of arsenic now have a potentially even bigger problem: recent research shows that arsenic-polluted water is tastier than normal water, and is addictive. “It’s a shame that we have taken so long to discover the addictive nature of arsenic,” says environmental scientist Dipankar Chakraborty.

Groundwater in the affected districts of West Bengal and Bangladesh have 30 times more arsenic content than what is regarded safe. The problem is alarmingly worse in Bangladesh, where some 70 million people —more than half the country’s population—are at risk from arsenic-contaminated water.

The addictive nature of arsenic makes it even more difficult to find a solution to this huge crisis. Says Chakraborty, “Upto four million people sick with chronic arsenic poisoning have got so used to drinking arsenic ground water that they have acquired a taste for the water of death.”

Arsenic is a slow, versatile and gruesome killer, attacking living tissues and in many cases damaging blood vessels. People get skin disorders and cancerous tumours leading to almost inevitable death. The milder disorders it triggers include conjunctivitis, nausea, diarrhoea and fatigue. Affected people are easily recognisable: inflamed eyes, skin lesions, gangrene and skin growths. As arsenic takes over the body, nails rot and horrific skin conditions develop.

Arsenic accumulates slowly in the body until it reaches lethal levels, and stays in the system for months even if only uncontaminated water is administered. The body has no mechanism to eject arsenic quickly; it is slowly removed in hair, nail and skin.

Arsenic, in the form of insoluble salts, occurs naturally in the bedrock below the alluvial deposits of the Ganga-Bramhaputra delta in Bangladesh and West Bengal. Under normal conditions, the ground water stays relatively free of arsenic. But because of uncontrolled exploitation of ground water to meet increased demands for water, arsenic becomes active and enters the ground water, affecting people who get drinking water from handpumps.

Most of those affected in Bangladesh and West Bengal are poor subsistence farmers, who now also face social ostracism because of the skin lesions caused by arsenic. There have been many instances of broken marriages, as husbands send their disfigured wives back to parental homes. There are also those who see their sores as divine punishment and refuse to see a doctor; it’s a different matter that most wouldn’t be able to afford the expensive medical treatment

Prevention against arsenic poisoning.is not very difficult. There are simple strategies which can help lower the levels of poison in water. Like using a modified clay tube which absorbs the arsenic. Or letting the water stand overnight to allow the iron and arsenic in the water to bind together and sink to the bottom before filtering it through a bale of hay.

Equally important as prevention or cure is to raise awareness about arsenic’s lethal effects. In Bangladesh, contaminated handpumps are painted red to warn users, but it is not of much help since many villagers have no other source of water. In West Bengal, an awareness campaign to educate students and their families through schools is planned.

But first, scientists have to get their act together. Says Chakraborty, “We need to understand the precise nature of the problem first—including the addictive properties of arsenic.” They have to be quick with that, time is running out for 100 million people.