Air pollution has a significant influence on acute human
mortality, which is overall greater than influences from weather,
and varies with season and the entire weather situation present.
Stronger effect estimates are found for respiratory mortality
than cardiovascular or all-cause. The risk of dying due to
exposure to all air pollutants from respiratory-related causes is
significantly higher than that of cardiovascular causes in 61% of
the cases, with the RR found to be 6e10% greater, on average.
The combined effect of weather and air pollution is greatest
when tropical-type weather is present in the spring or summer.
Dry tropical days are found to be most harmful in spring for
both causes of mortality, and in the summer for cardiovascularrelated
mortality. The spring season presents the overall greatest
risk of respiratory-related death compared to cardiovascular;
in particular, the risks due to air pollution exposure are highest
on DT and MT days, with CO and NO2 the most harmful air
pollutants.
These results underscore the importance of addressing the
cause of mortality, full weather type, and season, when estimating
the mortality risk of air pollution exposure. This epidemiological
study gives evidence to environmental-health policy makers to
proactively implement prevention strategies to reduce all levels
ambient air pollutants. Further, since all weather and air pollution
types present significant health risks, it is suggested that any
reduction in ambient pollution levels is a benefit to human health.
The investment in early warning systems based on synoptic
meteorological forecasts, such as an integrated weather-pollution
index, is suggested in order to predict accurate spatiotemporal
health outcomes for the public. This study demonstrates the potential
usefulness in estimating precise short-term future health/
pollution problems associated with specific incoming synoptic
weather patterns for each season.