Effect of sulfur dioxide and particulate pollutants on bronchitis in children--a risk analysis.

The general morbidity is being influenced to a great extent by diseases of the respiratory tract. Since their incidence and prevalence have been increasing, the identification of causal factors, especially of environmental origin, is of importance, not just in view of implementing preventive control strategies. Primary irritative gaseous [like sulfur dioxide (SO2)] as well as particulate pollutants (like TSP) can be regarded as causal constituents. Using the opportunity of changing levels of ambient air pollution in East Germany since 1989, the impact of SO2 and TSP on bronchitis was investigated over the last 10 years as part of several intervention studies in a locally defined homogenous population, children. The data suggest a significant association between SO2 and the prevalence of bronchitis in children but not for TSP. Considering the findings of other studies with respect to air pollution and the epidemiology of adverse health effects (especially respiratory disease), these results would amend the hypothesis put forward in a review of the literature as TSP < ultrafine particles (SO4(2-)) = SO2. Although these data show a significant association with only SO2, this does not imply that ultrafine particles, such as SO4(2-), do not contribute to the association with the observed adverse health effects. Nevertheless, the findings suggest that TSP seems less likely to be a predictor in the association with respiratory diseases, particularly not in the presence of high SO2.