The main causes of air pollution include the emission of greenhouse gases, such as carbon dioxide, methane, and chlorofluorocarbons, emission from volcanic eruptions and toxic air pollutants emitted by vehicles. The amount of smog as well as the damaging effects on health and the environment indicate the severity of air pollution.
Although it’s also produced through the breathing process, the vast amount of carbon dioxide responsible for air pollution comes from activities that include the burning of fossil fuels such as gasoline. As of 2014, the amount of carbon dioxide that has been released into the atmosphere by vehicles and power plants in the past 150 years has negatively contributed to global warming.
Methane comes from sources such as swamps and is a result of the digestion process in livestock. Chlorofluorocarbons had been used as refrigerants and aerosol propellants before they were banned on account of their harmful effect on the ozone layer.
The process of vehicle manufacturing, refueling and disposal creates two forms of air pollution: primary and secondary. Primary pollution affects the atmosphere directly, while secondary pollution functions through the interaction between different pollutants in the air. Particulate matter is a result of diesel exhaust and secondary pollution caused by hydrocarbons, nitrogen oxides, and sulfur dioxides. It consists of small particles of soot and metal that can severely impact a person’s health because they are able to penetrate deep into the lungs.