In Photos: Bangladesh's Arsenic Crisis — 'The Largest Mass Poisoning of a Population in History'

Millions of Bangladeshis are drinking deadly, arsenic-laced water two decades after the problem came to international attention, according to a Human Rights Watch report released this month — an Earth Day reminder that around the world many people continue to lack basic access to clean water.

Bangladesh's arsenic crisis, which the World Health Organization has called "the largest mass poisoning of a population in history," kills 43,000 people annually. According to one estimate, up to 5 million children born there between 2000 and 2030 will die from arsenic in their water supply.

Arsenic is a toxic, naturally occurring sediment found in soil in vast parts of Bangladesh and Southeast Asia. In large cities like Dhaka, clean water is either drawn from deep underground or purified. But in many rural regions, residents rely on an estimated 10 million hand-pumped, usually shallow tube wells to bring potentially contaminated water to the surface for use.

Richard Pearshouse, a Humans Rights Watch senior researcher who authored the report, said that the Bangladeshi government isn't taking even the most "basic, obvious steps" to remove arsenic from the drinking water that 20 million Bangladeshis — mostly rural poor — rely on.

"The government acts as though the problem has been mostly solved, but unless the government and Bangladesh's international donors do more, millions of Bangladeshis will die from preventable arsenic-related diseases," Pearshouse said.

The Human Rights Watch report was based on 134 interviews conducted throughout five villages in Bangladesh, with people suspected to be afflicted with arsenic-related health conditions, caretakers of government wells, and with government and NGO officials.

In 1995 an international conference drew global attention to arsenic in Bangladesh's groundwater, and over the next decade 5 million wells across the country were tested. Screenings showed that 20 percent of the country's tube wells — which provided water for 20 million people — were laced with dangerous levels of arsenic.

Today, with those numbers remaining roughly the same, Human Rights Watch placed the blame on "nepotism and neglect."The Bangladeshi government has been building new, deeper wells, but they often aren't installed where they are needed most. Of 125,000 wells installed by Bangladesh's government between 2006 and 2012, just over a third went to areas where less than half of the water was safe. One in 10 wells were installed in places already fully covered by safe water.

"Bangladesh should not allow national and local politicians to divert these life-saving public goods to supporters and allies," Pearshouse said. "Contaminated government tube wells urgently need to be replaced or rehabilitated, before people lose what little faith they have left in the government's commitment to provide safe water."

Khaddro, a farmer in his 30s who lives in Ruppur village, suspects his health conditions can be traced back to arsenic. He told Human Rights Watch that many government wells are installed in private homes.

"The owners bribe government people or use their political connections. We don't even know where some of them are, they're so secretive," he told Human Rights Watch. "It makes me very angry to think about this."

Khobar, who has arsenic-related skin lesions on his chest and feet, is a farmer in his mid-30s in Bilmamudpur village. He told organization that the area has no government-installed water sources.

"Look at my children! Even if we feed them as best we can and look after them well, they will fall sick from arsenic in the water," he said.

Follow Darren Ankrom on Twitter: @darrenankrom

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