Short-term Effects of Air Pollution on the Mortality. Results of the EMECAM Project in the city of Vitoria-Gasteiz, 1990-1994

Abstract

Background: The objective of this article is that of assessing the short-term relationship between the black smoke (SM) and SO2 levels and the mortality in Vitoria-Gasteiz over a five-year period by means of employing the procedure for analysis standardized in the EMECAM Project. Methods: Ecological time series study aimed at estimating the relationship between the daily fluctuations in the death rate (total mortality of all ages and total mortality for those over age 70) and air pollution (sulfur dioxide-SO2 and black smoke), employing the Poisson regression models. The EMECAM methodology was followed. Results: The mediam of daily deaths was three for the entire population and two for the elderly. The mean black smoke level was 51.15 m g/m3 and that of SO2 18.04 m g/m3. A statistically significant relationship was found to exist between black smoke and the mortality for the elderly through the cold half of the year, with an RR of 1.014 (CI95%: 1.002-1.026), pertinent to a 10 m g/m3 rise in the pollutant. A threshold at 80-90 m g/m3 seemed to be detected for fog. The relationship with SO2 was not significant. Conclusions: The black smoke levels for the period studied are related to a rise in the mortality among the elderly, tallying with the results of other studies.