Carbon Monoxide | Hydrocarbons Nitrogen Oxides | Particulate Matter Air pollution in the United States comes from many types of engines, industries, and commercial operations. Pollution sources that move, such as trucks, snowblowers, bulldozers, and trains, are known as “mobile sources.” Examples of all other (non-mobile) sources of air pollution include power plants, factories, and manufacturing processes. Mobile sources pollute the … Continue reading Pollutants