Air pollution and allergic disease. Report of a Working Party of the British Society for Allergy and Clinical Immunology.
Asthma and other types of allergic disease such as allergic rhinitis are increasing in prevalence throughout the western world. This report has reviewed the available world literature to examine the evidence that this increase is related to air pollution and to identify areas of uncertainty which need further research. We have restricted our review to aspects which are of direct relevance to allergic disease. In particular we have not addressed links between air pollution and increased cardio-respiratory mortality. There is good evidence that a number of air pollutants including sulphur dioxide, nitrogen dioxide, ozone and particulates, if present at sufficiently high concentrations, can exacerbate existing allergic disease, particularly asthma. Such concentrations are not infrequently found in the U.K. during episodes of poor air quality. The evidence that air pollutants cause problems at concentrations below internationally accepted guidelines (which are not, however, comprehensive) is not conclusive, although there is no room for complacency. In view of the frequency with which guidelines are breached and the risk to health this poses, the working group regard reducing air pollution in the U.K. as an important priority. The evidence that air pollutants, either from 'old style' fossil fuel burning, or from automobiles has contributed to the increase in the prevalence of asthma and allergy, other than through unmasking occult disease, is inconclusive although definitive studies are lacking. Similarly evidence to support the hypothesis that air pollutants act as adjuvants to increase the risk of becoming atopic is weak. The working party recommends detailed and comprehensive monitoring of air pollution concentrations across the U.K., development of techniques to measure individual exposure, research into the interaction between air pollutants and allergens and a major research effort into the effects of particulates. We would also welcome large, long-term, cohort studies to answer as definitively as possible whether exposure to increased air pollution increases the risk of becoming allergic.
Wardlaw
A J
AJ
Department of Respiratory Medicine, Glenfield Hospital NHS Trust, Leicester, U.K.
D000397:Air Pollution; D006801:Humans; D012130:Respiratory Hypersensitivity; D006113:United Kingdom