A3.2.2 Nitrogen


Nitrogen Oxides

NOx is a combined term used to refer to nitrogen oxides: Nitric Oxide (NO) and Nitrogen Dioxide (NO2). Nitric Oxide is usually very rapidly oxidised to Nitrogen Dioxide when released into the atmosphere.

Nitrogen Oxides are produced naturally by bacterial action, lightening and volcanoes. The natural sources produce more Nitrogen Oxides than the man made sources (Nitrogen itself is the most abundant component of air). The man made sources of Nitrogen Oxides include the combustion of fossil fuel from power generation and road transport.

Nitric Oxide does not have any known adverse health affects. However, according to http://www.airquality.co.uk, “Nitrogen Dioxide can irritate the lungs and lower resistance to respiratory infections such as influenza.”

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Ammonia (NH3) is normally present as a gas, which has a pungent odour (although a liquid, urine contains ammonia).

Ammonia is often emitted as a result of farming and agricultural processes.

Ammonia is known to cause damage to sensitive habitats, particularly heathlands, affecting plants and biodiversity. The consequence of ammonia pollution causes environmental problems to vegetation, soils and water. Ammonia also contributes to long-range acidification. Heathlands are particularly sensitive and ammonia pollution can cause heathlands to be taken over by grass. Moss-dominated heathlands in upland areas of Britain are also reduced and species of vegetation that only require low levels of nutrients are also lost.