Environmental pollution is caused by several sources, including human and anthropogenic activities. Most environmental pollution comes from human sources and enters into the atmosphere, streams and soils. Factories, transportation vehicles — including cars, trains and planes — and negligent agricultural and construction practices are all common and widespread sources of pollution.
Air pollution is one of the most widespread types of environmental pollution. This type of pollution comes from the collection of toxic chemicals and additives in the atmosphere that are released by sprays, liquids and the conversion of fossil fuels into energy. Similarly, water pollution comes from abnormally high levels of synthetic chemicals that leach into streams from runoff and via precipitation.