UK Air Pollution
Air pollution in the UK has been a recognised problem as far back as the 13th century, when the use of coal in London was prohibited on the ground that it was prejudicial to health. During the Industrial Revolution, smog pollution in urban areas became a significant problem, due to the industrial and domestic burning of coal. Today, both urban and rural smog pollution results from the build up of secondary photochemical pollutants such as ozone. Whilst air quality generally has improved during the last 100 years, legislative controls and the introduction of further low emission technology will help to reduce air pollution in the UK still further.
Since the Clean Air Acts of 1956 and 1968, emissions of sulphur dioxide and smoke in the UK have fallen dramatically. Sulphur dioxide emission control was given additional assistance in 1979 with the Convention on Long-Range Transboundary Pollution, designed to limit the spread of transboundary pollution that was causing acid rain. Further international protocols which tackled the acid rain problem during the 1980s by reducing emissions of nitrogen oxides have had less success. Whilst industrial nitrogen oxides emissions have fallen in the last 15 years, emissions from road transport have grown significantly, because of the increase in the number of cars, although in the last few years the introduction of clean fuel technology has helped to reduce emissions. Similarly, emissions of particulates, carbon monoxide and volatile organic compounds (VOCs) from road transport have increased, although as for nitrogen oxides, these emissions are now starting to fall.
The shift in type of emissions, from domestic and industrial to road transport, has resulted in a shift in type of common pollution episode. The sulphurous and smoky winter smogs of the 19th century have been replaced by summertime photochemical smogs consisting of ozone and other secondary pollutants. In addition, such photochemical pollution (pollution formed by the action of sunlight) is generally highest in rural areas, due to its special atmospheric chemistry.
The UK National Air Quality Strategy, published 1997, sets air quality standards and guidelines for nitrogen dioxide, sulphur dioxide, carbon monoxide, particulates, VOCs and ozone. Many of these targets will need to be met by 2005. The standards most commonly exceeded in the UK are those for ozone and particulates.