2de55cd4_ealth_Effects_of_Air_Pollution__Sources
[Air Pollutant] Carbon Monoxide [Health Effects] Carbon monoxide reduces the oxygen carrying capacity of red blood cells. The health effects depend on the duration of exposure and the concentration of carbon monoxide inhaled. Typical symptoms of exposure to low levels of carbon monoxide include headache, dizziness and tiredness. Higher concentration of carbon monoxide can lead to impaired vision, disturbed coordination and eventually death. [Sources] 
Carbon monoxide is produced primarily by incomplete combustion of fossil fuels. In Hong Kong, the majority of ambient carbon monoxide comes from vehicular emissions.
Centre for Health Protection - The Health Effects of Air Pollution
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