Harmful effects of air pollution are: 

1. Due to half or incomplete combustion of petrol and diesel, CO a poisonous gas is produced, it decreases the capacity of oxygen carrying in blood. 

2. Tetra ethyl lead present in petrol is a dangerous pollutant. It is one of the factors of cancer and tuberculosis. 

3. In winters a thick layer of smog is formed due to fog and smoke. It contains NO₂ which causes asthma, cough and disorder of respiration. 

4. From Petrol Refineries NO₂ and SO₂ pollutants, we released as gas waste products. Fuel used in power plants also produce SO₂. These pollutants are harmful and cause diseases related to lungs.

5. Chloro Floro Carbon (CFC) is a type of air pollutant. It is used in refrigerators and Air conditioners. It harms the Ozone layer of atmosphere. It protects us from ultraviolet rays of the sun. Due to excess dissolution of CFC in air the hole in the ozone layer is increased and created an acute problem.

6. Gases emitted out of Industries like – SO₂, Cl₂, NH₃, N₂O cause burning in eyes and throat diseases. 

7. Manufacturing industries of Aluminium and Super phosphate produce poisonous gases which cause many diseases. 

8. Air pollution also cause harm to plants. SO₂ even causes death of plants.