What is Ozone pollution?

About Ozone pollution:

• Ozone (O3) high in the Earth's atmosphere protects us from the sun's harmful radiation. But ozone at ground level (tropospheric ozone), is an air pollutant that harms people and plants. 
• Ground-level ozone is a colorless and highly irritating gas that forms just above the earth's surface.
• How ground level ozone is formed?
  • It is called a "secondary" pollutant because it is produced when two primary pollutants react in sunlight and stagnant air. 
  • These two primary pollutants are nitrogen oxides (NOx) and volatile organic compounds (VOCs).
  • These precusrsor primary pollutants are each produced primarily by a variety of human activities, including burning of fossil fuels and various industrial processes. Certain types of volatile organic compounds can also be emitted from natural sources.
• Impacts:
  • Ground-level ozone is known to have significant effects on human health. Exposure to ozone has been linked to pre-mature mortality and a range of morbidity health issues.
  • It can significantly impact vegetation and decrease the productivity of some crops.  
  • It can also damage synthetic materials, cause cracks in rubber, accelerate fading of dyes, and speed deterioration of some paints and coatings.

Source:   Why ozone prominent pollutant over past two days in Delhi