Air pollution, The presence of harmful toxic compounds in extreme quantities in the air results in air pollution. The primary sources of air pollution are harmful gases like sulfur dioxide, carbon dioxide, carbon monoxide, nitrous oxide, nitrogen dioxide, and other suspended particles., Air pollution is usually caused by burning fossil fuels like petroleum, and coal-burning of wood and cow dung cakes in homes, factories, vehicles, and power plants. Among all other continents globally, India is the country with the most polluted cities. Lucknow, Kanpur, New Delhi are a few among them because of excessive use of fossil fuels by vehicles and other industrial units., Water pollution, The contamination of water bodies, such as lakes, rivers, oceans, underground water and seas by harmful substances is water pollution. The leading cause of water pollution is sewage, industrial wastes, pesticides and fertilisers from farming., Polluted water becomes unfit for drinking, bathing, washing, and irrigation. Garbage dumping can also leak out pollutants into underground water., The major water pollutants are lead, mercury, fertilisers and pesticide compounds. The sewage and industrial wastes from tanning factories are the primary sources of the Ganga river’s pollution., Soil Pollution, Soil pollution is the contamination of soil due to harmful substances. Polluted soil becomes unfit for growing crops and plants, and is usually accompanied by water pollution. The significant causes of soil pollution are over-irrigation, usage of pesticides, dumping of sewage and garbage, deforestation and mining. The most common soil pollutants are heavy metals like lead and mercury, pesticide compounds, salt and mineral ores. These pollutants disturb the soil profile, spoil the soil fertility and make it unfit for growing crops.