[Surveillance of short-term effects of urban air pollution on mortality. Results of a feasibility study in 9 French cities].
BACKGROUND: This study aims at quantifying air pollution effects on mortality and at evaluating the feasibility of a standardized epidemiological surveillance system of air pollution in 9 French cities. METHODS: Data collection and analysis followed a standardized protocol. Data pollution depended on the development of local air quality surveillance networks (number of indicators, number of stations.). The Generalised Additive Models (GAM) were used to quantify the association between air pollution and mortality. RESULTS: In the 9 studied areas, associations between all causes, cardiovascular and respiratory mortality, and air pollution indicators were observed. These associations were linear without threshold. Depending on the pollutants, excess in mortality related to an interquartile increase in acid-particulate pollution varied between 0.3 and 3.5% for total mortality, 0.5 and 6.3% for cardiovascular mortality, and between 0.1 and 12% for respiratory mortality. Photochemical air pollution varied between 0.4 and 7.3% for total mortality, 1.4 and 6.7% for cardiovascular mortality, and between 1.7 and 30.4% for respiratory mortality. CONCLUSION: In spite of a standardized common protocol, some disparities, inherent to the local characteristics, were noted (length of time series, numbers of ambient urban stations selected and pollutants available.). Nevertheless, this pilot study showed that multicentric epidemiological monitoring of air pollution effects on health was feasible. Yet, this requires to validate the results obtained through a re-analysis of the mortality data on a longer period of study. It also requires to study the feasibility and the relevance of the use of other health indicators, such as hospital admissions.