Air pollution is a group of substances in the atmosphere that can harm the health of people, animals, and plants. It can also damage buildings and materials.
There are many sources of air pollution. Some are natural, such as smoke from wildfires and ash from volcanoes. Others are human-made, like emissions from cars, factories, and other sources.
Water pollution is the discharge of harmful substances into water bodies, which can have a detrimental effect on fish and other organisms. Often, these pollutants are harmful to the ecosystem as a whole because they can change the growth conditions in rivers, lakes, and oceans.
Water pollutant sources include point and dispersed sources. Examples of point sources are industrial effluents and sewage systems, while dispersed sources are runoff from agricultural areas or debris that is blown into waterways by rain or wind.
Soil pollution is the build-up of toxic compounds, chemicals, salts or radioactive materials that have adverse effects on the health and growth of plants or animals. This can cause crop losses and the extinction of animal species.
Soils can be polluted by many different sources, including industrial chemicals and wastes. They can also be contaminated by soil contaminants found naturally in the environment.