Pollution.

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.

Air Pollution, water pollution, and land pollution are three major forms of environmental pollution. Pollution can also refer to excessive human activity, such as light and noise pollution, or to specific pollutants such as plastic or radioactive material.

Pollution can be reduced through processes such as recycling and the proper treatment of water and toxic waste. The reduction of corporate fossil fuel extraction is another way to counter air pollution. According to the Carbon Majors report prepared by the Carbon Disclosure Project, more than 70 percent of greenhouse gas emissions comes from only 100 companies.