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Air Pollution Briefing

Air pollution is a significant issue around some airports. At Heathrow it is currently a ‘show stopper’ for the proposed third runway. AEF has produced a briefing which provides both background information on air pollution and identifies key issues around airports and air pollution. In particular, the statements in the White Paper about air pollution are analysed and the ensuing work programme is described.


Air pollution – a big issue

Air pollution is, or ought to be, a big issue. A government study estimated that 12,000 to 24,000 people die early every year in the UK from the acute effects of air pollution. Many more die from long-term effects.The pollutants of most concern are:

  • Small particulates – also referred to as PM10
  • Nitrogen dioxide or NO2 – a particular chemical combination of nitrogen and oxygen
  • Ozone or O3 – a very reactive form of oxygen.

Air Quality Standards

Various organisations have set standards for air quality. These are levels of pollution should not be exceeded, so as to protect human health. The UK government has set ‘objectives’ for PM10 and NO2 and the EU has also set mandatory limits. The objectives for the UK are incorporated in UK air quality legislation.In addition to standards to protect human health, standards have also been set to protect vegetation and ecosystems for NO2 and ozone. These standards are in some cases more stringent than the health standards, but they carry less legal weight.

Air pollution and aviation

Jet engines produce relatively few particulates, concentrations of these tending to be dominated by road traffic and sometimes by non-transport sources. NOx/NO2 is produced in large quantities by aircraft engines, although road traffic is usually still the biggest single source, except close to runways. The contribution of aircraft to the other pollutants noted above is minor, except in the case of ozone, where NOx is a precursor.

White Paper

The White Paper aviation says that none of the airport options will breach the standards for particulates. But this may only be because the new standards are far weaker than the original standards. The original standards were set purely on health grounds – the new ones are weaker for reasons that can best described as political expediency.There will be breaches of standards for N02 around airports with several of the expansion options. By far the biggest problem is at Heathrow where 35,000 people could be exposed if a third runway was built. As a result, expansion at Heathrow could fall foul of the EU. A somewhat dubious ‘sensitivity test’ is quoted which shows that only 5000 people would be exposed if more optimistic assumptions are made.

Ozone is a very dangerous pollutant but is ignored in the White Paper.

There are many other effects of air pollution including corrosion of buildings and structures, soiling of materials, interference with agriculture, damage to habitats, local extinction of species and acid rain. In some cases these effects are apparent at concentrations well below those at which human health is affected. The White Paper ignores these issues.Original standards, set to protect human health and the environment, have been set aside in favour of a ‘legalistic’ approach whereby only breaches to mandatory standards EU are considered.

Full briefing

For more information on these issues, see our 15 page briefing (Word document) on ‘publications’ below:Air Pollution Briefing