Pollution is the introduction of harmful materials into the environment These harmful materials are called pollutants
Pollutants can be natural, such as volcanic ash
They can also be created by human activity, such as trash or runoff produced by factories Pollutants damage the quality of air, water, and land
Major forms of pollution include air pollution, light pollution, litter, noise pollution, plastic pollution, soil contamination, radioactive contamination, thermal pollution, visual pollution, and water pollution
