Air Pollution
The United States produces more air pollutants than any other country, most of which are released via transportation, particularly by cars. The escalating number of drivers and cars on the road contributes greatly to human health problems and global climate change because almost every stage of a car's life, from its production to its fueling, is detrimental to the air.
Pollutants
Vehicles produce several types of air pollutants. For humans, among the most harmful are hydrocarbons and nitrogen oxide, which combine to form smog; particulate matter, which is harmful to lungs; and carbon monoxide, which is formed from the combustion of gas. The latter blocks oxygen's circulation in the body, a particular risk for the very young and very old. More than half of the cancers traced to air pollution are caused by a car's hazardous pollutants. In the atmosphere, substances like carbon dioxide, produced from the burning of gasoline in a car's engine, contribute greatly to the greenhouse effect and debilitating climate change.
Solutions
There are a plethora of solutions to dampen a car's impact on air pollution. Driving less by using smaller electric vehicles, bikes or public transportation is important, as is buying hybrids or cars with computers to help attain optimal engine performance. Another help would be using alternative fuels and energy sources, an option many scientists are working on with an eye to the future.