Lung function and long term exposure to air pollutants in Switzerland

The effect of long-term exposure to air pollutants was studied in a cross-sectional population-based sample of adults (aged 18 to 60 yr; n = 9,651) residing in eight different areas in Switzerland. Standardized medical examination included questionnaire data, lung function tests, skin-prick testing, and end-expiratory CO concentration. The impact of annual means of air pollutants on FVC and FEV(1) was tested (controlling for age and age squared, sex, height, weight, educational level, nationality, and workplace exposure). Analyses were done separately for healthy never-smokers, ex-smokers (controlling for pack-yr), for current smokers (controlling for cigarettes per day and pack-yr smoked), and for the whole population. Significant and consistent effects on FVC and FEV(1) were found for NO2 SO2 and particulate matter < 10 mu m (PM(10)) in all subgroups and in the total population, with PM(10) showing the most consistent effect of a 3.4% change in FVC per 10 mu g/m(3). Results for ozone were less consistent. Atopy did not influence this relationship. The limited number of study areas and high intercorrelation between the pollutants make it difficult to assess the effect of one single pollutant. Our conclusion is that air pollution from fossil fuel combustion, which is the main source of air pollution with SO2 NO2 and PM(10) in Switzerland, is associated with decrements in lung function parameters in this study.