Elemental concentrations of ambient particles and cause specific mortality in Santiago, Chile: A time series study

Abstract

Background: The health effects of particulate air pollution are widely recognized and there is some evidence that the magnitude of these effects vary by particle component. We studied the effects of ambient fine particles (aerodynamic diameter < 2.5μm, PM2.5) and their components on cause-specific mortality in Santiago, Chile, where particulate pollution is a major public health concern. Methods. Air pollution was collected in a residential area in the center of Santiago. Daily mortality counts were obtained from the National Institute of Statistic. The associations between PM 2.5 and cause-specific mortality were studied by time series analysis controlling for time trends, day of the week, temperature and relative humidity. We then included an interaction term between PM2.5 and the monthly averages of the mean ratios of individual elements to PM2.5 mass. Results: We found significant effects of PM2.5 on all the causes analyzed, with a 1.33% increase (95% CI: 0.87-1.78) in cardiovascul