FILE - Firemen use a hose to wet canvas screens at factory boundaries to prevent the spread of dangerous fumes at the Union Carbide plant in Bhopal, India, December, 1984. On Dec. 3, 1984, the pesticide plant run by Union Carbide leaked about 40 tons of deadly methyl isocyanate gas into the air, killing an estimated 15,000 people and affecting at least 500,000 more. Michigan-based Dow Chemical Co. took over Union Carbide in 2001. (AP Photo/Peter Kemp, File)