The Atmosphere, Climate & Environment Information Programme is a Government sponsored web site providing a comprehensive and regularly updated source information on the health effects, behaviour and improvement of air quality.
There is also a large amount of information available in network and local authority reports, downloadable from the reports pages.
More local information may be available on the web site of your local authority.
Links to other organisations such as Defra, the National air quality network (AURN) and other regional monitoring networks.