The effects of particulate and ozone pollution on mortality in Moscow, Russia

Abstract

The objectives of this study were (1) to evaluate how acute mortality responds to changes in particulate and ozone (O(3)) pollution levels, (2) to identify vulnerable population groups by age and cause of death, and (3) to address the problem of interaction between the effects of O(3) and particulate pollution. Time-series of daily mortality counts, air pollution, and air temperature were obtained for the city of Moscow during a 3-year period (2003-2005). To estimate the pollution-mortality relationships, we used a log-linear model that controlled for potential confounding by daily air temperature and longer term trends. The effects of 10 mug/m(3) increases in daily average measures of particulate matter </=10 mum in aerodynamic diameter (PM(10)) and O(3) were, respectively, (1) a 0.33% [95% confidence interval (CI) 0.09-0.57] and 1.09% (95% CI 0.71-1.47) increase in all-cause non-accidental mortality in Moscow; (2) a 0.66% (0.30-1.02) and 1.61% (1.01-2.21) increase in mortality from ischemic heart disease; (3) a 0.48% (0.02-0.94) and 1.28% (0.54-2.02) increase in mortality from cerebrovascular diseases. In the age group >75 years, mortality increments were consistently higher, typically by factor of 1.2 - 1.5, depending upon the cause of death. PM(10)-mortality relationships were significantly modified by O(3) levels. On the days with O(3) concentrations above the 90th percentile, PM(10) risk for all-cause mortality was threefold greater and PM(10) risk for cerebrovascular disease mortality was fourfold greater than the unadjusted risk estimate.