NATIONAL POLLUTION CONTROL DAY,METHYL ISOCYANATE, BHOPAL GAS TRAGEDY,INDIA OBSERVES NATIONAL POLLUTION CONTROL DAY , NATIONAL POLLUTION CONTROL DAY OBSERVED ON DEC 2nd, POLLUTION CONTROL DAY IN MEMORY OF VICTIMS OF BHOPAL GAS TRAGEDY, BHOPAL GAS TRAGEDY: WORLD'S BIGGEST INDUSTRIAL DISASTER