Air pollution is solid, liquid or gaseous substances that change the natural composition of air. Air pollution sources can be characterized in two categories one from stationary sources & other from mobile sources. Stationary sources of air pollution consists of Combustion of fuels for power and heat, other burning such as incineration or forest fires, Industrial/commercial processes & Solvents and aerosols whereas mobile sources of air pollution are Highway vehicles: cars, trucks, buses, and motorcycles & Off-highway vehicles such as aircraft, boats, locomotives, farm equipment, RVs, construction machinery and lawn mowers.
According to the Environmental Protection Agency, motor vehicles produce around 16 percent of pollutants in the environment. Seventy-five percent of carbon monoxide emissions come from automobiles. The main pollutants from the automotive are carbon monoxide, Volatile organic compounds (VOCs), NOx, Ozone, Lead, Particulate matter (PM), Carbon Dioxide & Carbon Particles. These pollutants affect the human circulatory system, heart, lungs, respiratory system, brain, cancer & nervous system.
Sources of Automotive Emissions
· Engine Crankcase Blow-by Fumes (20%) – heating oil and burning of fuel that blows past piston rings and into the crankcase.
· Fuel Vapour (20%) – chemicals that enter the air as fuel evaporate.
· Engine Exhaust (60%) - blown out the tailpipe when the engine burns a hydrocarbon-based fuel.
In addition, the introduction of environmentally friendly technologies like hydrogen, fuel cells, electric/electric-hybrid, etc. would also help.
Source & Image Courtesy: Auto how stuff works,