Definition and scope of air pollution

Summary

Air pollution is the presence of substances in the air that are harmful to humans, other living beings, or the environment. These pollutants can be gases (such as ozone or nitrogen oxides) or small airborne particles (such as soot and dust). Air pollution can occur both outdoors and indoors, meaning everyday environments like homes and workplaces can also be affected. The scope of air pollution includes a wide range of sources. Outdoor air pollution commonly comes from burning fossil fuels for electricity and transport, wildfires, some industrial processes, waste management, demolition, and agriculture. Indoor air pollution is often linked to burning firewood or agricultural waste for cooking and heating, and can also be influenced by household fuels and building materials. Natural events such as dust storms, volcanic eruptions, and emissions from vegetation and wildfires also contribute. Air pollution is not limited to local effects: many pollutants can travel and transform in the atmosphere, and some sources also emit greenhouse gases that contribute to global warming. Because air pollution affects health and ecosystems, its scope extends to major pollutants (including particulate matter and ground-level ozone) and to the broader social and environmental impacts they cause.

Key Points

• 1

  Air pollution refers to harmful substances in the air, including both gases and airborne particles, indoors and outdoors.

• 2

  Major human sources include fossil-fuel burning (power and transport), industry, waste burning/management, construction/demolition dust, agriculture, and household cooking/heating.

• 3

  Natural sources such as dust storms, volcanic eruptions, vegetation emissions, and wildfires also contribute to air pollution.

• 4

  Air pollution can have effects beyond the immediate location through atmospheric transport and chemical transformation, and it can intersect with climate change through greenhouse gas emissions.