- airway obstruction
- Atopic allergy
- chemical pollution
- environmental factors
- gene pool
- Hygiene hypothesis
WR 06 : Workshop on Chemical Pollution, Respiratory Allergy and Asthma | February 2006
Atopic allergy and asthma remain important health issues. It is therefore of significance that in more modernised societies there has, during the last four decades, been a substantial increase in the prevalence of these diseases. The observed changes have been too rapid to be accounted for by modifications to the gene pool and there is a general acknowledgement that alterations in lifestyle, combined with changing environmental factors, are responsible for the increases in prevalence.
Against this background there has been speculation that exposure to some specific chemicals in particular, and chemical pollution in general, may play an important pathogenetic role. Several mechanisms through which this might occur have been proposed. However, there are in addition, a number of other factors that have been implicated as playing potentially important roles, and among these are diet (both quantity and quality), reduced exposure neonatally and during infancy to infectious micro-organisms, and changes in indoor air quality.
The purpose of this Workshop was to determine whether and to what extent chemicals have played a role in the increased burden of allergy and asthma in ‘westernised’ societies. It is clear that further research is required to define the factors that have impacted on the prevalence of asthma and atopic allergy. However, a major conclusion drawn was that although contributions by some types of chemical exposure have been suggested, in comparison with other acquired and environmental factors the contribution of chemicals is likely to have been modest.