2de55cd4_ealth_Effects_of_Air_Pollution__Sources
[Air Pollutant] Ozone [Health Effects] In the upper atmosphere, ozone shields the earth from the harmful ultraviolet radiation. In ground level, ozone is a highly reactive gas which can irritate the eyes and bring upper and lower respiratory symptoms to healthy people. It may also provoke asthmatic attacks in people having asthma. Ozone can also increase a person's susceptibility to respiratory infection and aggravate pre-existing respiratory illnesses. [Sources] 
Ozone is formed from photochemical reaction between nitrogen oxides and volatile organic compounds, which are predominantly pollutants from motor vehicles and industries.
Centre for Health Protection - The Health Effects of Air Pollution
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