The day highlights the need to prevent industrial disasters and cut pollution.
India observes National Pollution Control Day on December 2 in memory of those who lost their lives in the Bhopal gas tragedy of 1984.
On the night of December 2-3, 1984, methyl isocyanate gas leaked from the Union Carbide pesticide plant in Bhopal, killing thousands of people and affecting lakhs more. It is considered one of the world's worst industrial disasters.
The day aims to raise awareness about industrial safety and the prevention of air, water and soil pollution.
It comes as many Indian cities face their worst air quality of the year, and experts urge people to use public transport, avoid burning waste and support cleaner fuels.
