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Pollutant Fact Files

Look up the fact files about these nasty pollutants!

  • Nitrogen dioxide
  • Carbon monoxide
  • Ozone
  • Particulate matter
  • Sulphur dioxide

Nitrogen Dioxide (NO2)

Nitrogen dioxide

Nitrogen dioxide is a reddish, brown gas that doesn’t smell very nice. It's also toxic, which means it's poisonous and very harmful to humans. If you were to breathe in lots of nitrogen dioxide it would make breathing difficult, give you pains in your chest and it may damage your lungs.

Nitrogen dioxide is part of a family called 'Oxides of Nitrogen'. Its sister, Nitric Oxide (NO), is colourless, doesn't smell and isn't harmful to humans at all. But when nitric oxide comes into contact with oxygen (which is part of the air around us) it very quickly changes and becomes nitrogen dioxide, which is bad for us and the environment.

So, anything that emits nitric oxide into the air we breathe will be causing nitrogen dioxide pollution. This includes almost anything that burns fuels, especially cars and other vehicles.