It was on 3rd December 1984 that a cloud of poisonous gas escaped from an underground tank at the Union Carbide chemical factory in Bhopal, northern India. The official count of the deaths as a result of inhalation of the gas is 5,325 people - the real figure is probably more like 8000, and the tragedy of Bhopal is that people who breathed in the fatal gas, even the smallest quantity, are still dying today, 13 years on.