Up to 75 million people in Bangladesh could be threatened by arsenic poisoning which contaminates wells across the country.

Thirty years ago, aid organisations promised to provide safe drinking water for the people of Bangladesh by sinking deep tubewells across the country.

But instead of clean water, studies have shown that tens of millions of people across the country are being exposed to toxic levels of arsenic.

Arsenic is a naturally occurring chemical poisonous to humans and is known to cause skin lesions and cancers of the bladder, kidney, lungs and skin.

On this edition of 101 East, we look at how a plan to help one of the world's poorest countries went horribly wrong.

This 101 East episode airs from Thursday, August 12, 2010 at the following times GMT: Thursday: 1230; Friday: 0300; Saturday: 0530, 1730; Sunday: 1130; Monday: 0030; Tuesday: 0600, 1430; Wednesday: 0830; Thursday: 0630.

Source: Al Jazeera