Air pollution

Air pollution is understood as implementation of solids, liquids, or gases, which are foreign to the air composition, or natural substances excessively, which can be harmfully influential to human health, climate, living nature, soil, and water, or can cause other harms to environment. Air pollution emerges both from anthropological (unnatural) and natural sources. Substances emitted to the atmosphere can take the shape of aerosols (solid or liquid particles floating in the air, with diameter below 100 µm) or gases (SO22, NOx, CO itp.).

Main components of dry air without additives, with % content

Main air pollution
  • nitrogen (N2) - 78,08%
  • oxygen (O2) - 20,90%
  • argon (Ar) - 0,93%
  • carbon dioxide (CO2) - 0,03%
  • particulate matter
  • oxygen (O3)
  • nitrogen oxides (NO, NO2, N2O)
  • sulphur oxides (SO2, SO3)
  • carbon oxides (CO, CO2)
  • hydrocarbons
total: 99,99%

total: >90%


Primary pollution: emitted directly to the atmosphere from sources (majority of gas pollution: NO, SO2, CO, CH4, NH3), can affect environment directly or contribute to secondary pollution.

Secondary pollution: not emitted directly from the source, but emerging in the atmosphere as a result of chemical reaction of primary pollution; main secondary pollution are: tropospheric ozone (O3) which come into being as an outcome of reaction of nitrogen oxides (NOx) and hydrocarbons (HC) with the use of sunlight, particulate matter emerging from reaction of sulphur oxides (SOx) and nitrogen oxides (NOx), and nitrogen dioxide (NO2) from oxidation reaction of nitrogen oxide NO.


Elaborated by A.Drzeniecka-Osiadacz