Health impact of improved air quality during the Olympic Games 2008 in Beijing, China
Zusammenfassung der Projektergebnisse
Thee goal of this study was to assess the effects of improved air quality during the 2008 Olympic Games in Beijing, China. Therefore, detailed size-resolved measurements of particles in the size range between 3nm to 10μm and data on (cause-specific) respiratory mortality and emergency room visits (ERV) in a hospital close to the measuring site were obtained to distinguish between health effects of different fractions of particles. We investigated air pollution effects on daily respiratory mortality and ERV counts for the period May 20 to December 1, 2008 using confounder-adjusted Quasi-Poisson regression models. Furthermore, air pollution effects were estimated for three periods pre (May 20–July 20, 2008), during (August 1-September 20, 2008), and post (October 1–December 1, 2008) the Olympic Games and Paralympics by including an interaction term in the models. Additionally, the impact of the changing air quality over a longer time period (2007-2008) on health was analyzed. In summary, no air pollution effects were observed on respiratory ERV investigating the whole study period. However, our results so far suggest that a reduction of the air pollution concentrations - especially of particle number concentrations (PNC) - during the Olympic and Paralympic Games led to a reduction in respiratory mortality. Mortality rates continued to be decreased even in the post-Olympics period. When investigating a longer time-period (July 22, 2007 – December 31, 2008), we observed an increase for respiratory and pneumonia events in association with different PNC size ranges, and the effects were more pronounced in smaller particle size ranges (10-30nm, 30-50nm and 3-100nm). Higher pneumonia mortality and respiratory ERV counts were also associated with elevated NO2 concentrations. Moreover, we observed PM10 and PM2.5 effects on respiratory ERV counts. The findings further suggest that ultrafine particles may be particularly important for human health. At present, administrative air quality measurements of national networks, not only in China, measure only particle mass, such as PM10 or PM2.5. In the future, regular air pollution measurement systems should be extended by measurements of particle number concentrations. Overall, the project also improved the bilateral co-operation between the German and Chinese partners. The co-operation included the planning and performance of data sampling as well as the data analysis, and provision of training opportunities to the Chinese partners. The project further strengthened the scientific co-operation between the partner institutes in the field of health risks of urban aerosol.
