||The English used in this article or section may not be easy for everybody to understand. (January 2017)|
Pollution is when something is added to the environment harmful or poisonous to all living things. Smoke or dust in the air is a type of pollution . Sewage in drinking water is another type of pollution, containing germs and viruses. There are 3 kinds of pollution: water pollution, land pollution, and air pollution.
As pollution grows, ways to combat it have grown too. Solar energy and wind energy give people other ways to power their homes. When people use these alternative forms of energy, they put less carbon dioxide into the environment. 
Air pollution[change | change source]
Air can be polluted by many things. Air pollution includes poisonous gases, sulphur dioxide, nitrogen dioxide, carbon monoxide and very small particulates. Smoke and harmful gases released by fires, industries and thermal power plants cause air pollution. Using coal and wood as fuels for fire cause a lot of air pollution. Petroleum produces less pollution per tonne, but it causes a lot of pollution since a lot of it is burned globally. Air pollution may cause breathing problems such as asthma or other health problems. It also causes diseases like cancer.
Water pollution[change | change source]
Water pollution is the presence of harmful materials in water, such as sewage, dissolved metals, waste from farms, factories and crude oil spilled from oil tankers. The three main substances that pollute water are nitrates from fertilizers, sewage and detergents.
Activities such as bathing and washing clothes near lakes, ponds or rivers add nutrients like nitrate and phosphate into the water bodies.This leads to excessive growth of algae on the surface of water. It blocks the penetration of sunlight and air, thus reducing oxygen.
Noise pollution[change | change source]
Noise pollution (also known as sound pollution) is harmful to the brain and hearing of all animals and humans. This includes the sound of vehicles, loud speakers, airplanes, jets, train horns etc. Noise pollution can cause ear problems or even permanent deafness, especially to older people. It also causes brain related problems.
Land pollution or Soil pollution[change | change source]
Soil pollution (also known as land pollution) is caused when man-made chemicals, such as hydrocarbons, heavy metals, and solvents, get into the soil.These chemicals come from industrial activities and from improper waste in disposal in leaky landfills. Soil pollution can cause health risks. The chemicals can produce harmful vapours, or they can contaminate water supplies underneath the polluted soil.
Plastic pollution is the accumulation of plastic products in the environment that adversely affects wildlife, wildlife habitat, or humans. It is caused because plastic takes thousands of years to decompose or mix in the earth.
Thermal pollution[change | change source]
Thermal pollution is the harmful release of heated liquid into a body of water or heat released into the air as a waste product of a business.
A common cause of thermal pollution is the use of water as a coolant by power stations and industrial manufacturers. This puts back warm water, and so raises the temperature and decreases the oxygen content of the water.