2de55cd4_ealth_Effects_of_Air_Pollution__Sources
[Air Pollutant] Nitrogen Dioxide [Health Effects] Nitrogen dioxide irritates the mucosa of the eyes, nose, throat and the lower respiratory tract. Exposure to low level of nitrogen dioxide may cause increased bronchial reactivity and in those with asthma increased response to allergens. Nitrogen dioxide also aggravates existing chronic respiratory diseases. Long-term exposure to nitrogen dioxide can lower a person's lung function and resistance to respiratory infections. [Sources] 
High temperature combustion process results in nitrogen oxides emissions (including nitrogen dioxide), which may come from stationary sources such as power stations, and mobile sources such as motor vehicles.
Centre for Health Protection - The Health Effects of Air Pollution
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