Where Do They Come From?

Man-Made Sources

Sources of pollution caused by human activity include:

  • power plants - PM10 (Particulate Matter up to 10 micrometers in size), NOx , Sulphur , Benzene
  • waste incinerators - Sulphur , Benzene
  • motor vehicles - PM10 (diesel engines), N0x, lead (petrol), Benzene / Carbon monoxide (exhaust fumes)
  • aircraft
  • marine vessels
  • fertilisers
  • landfills
  • cigarette smoke - Benzene

Around 40% of air pollution can be attributed to the burning of fossil fuels. For example, one coal-fired power station can emit 16 million tonnes of CO2 a year.

 

Natural sources

Natural sources of air pollution are:

  • volcanoes - these produce chlorine, ash and sulphur
  • radon - this is found in radioactive decay in the Earth's crust
  • smoke - caused by wildfires
  • methane -  from animals' digestive systems
  • dust - from expanses of land with little or no vegetation: PM10
  • windblown sea salt – PM10
  • air masses – Ozone


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