Ambient
Air Pollution and Daily Mortality in
Taipei, Taiwan and Hong Kong, China
Teresa Chuang
The relationship between ambient air quality and daily mortality for the period 1997-1998 was examined in Taipei, Taiwan and Hong Kong, China. The observed yearly concentrations of respirable particulate matter (PM10) and sulfur dioxide (SO2) in each city were below the World Health Organization's 1999 air quality guidelines, though yearly nitrogen dioxide (NO2) levels in both cities exceeded the WHO's recommendations. Daily death counts-of total mortality, mortality of persons ³65, mortality due to cardiovascular disease, mortality due to respiratory disease, mortality due to pneumonia, and mortality due to COPD-were analyzed separately in the two cities by Poisson regressions for the overall two-year period as well as by season. Mortality rate ratios were calculated by identifying the 10% of days in the two-year time period with the highest and lowest concentrations of each air pollutant, and comparing the mortality rates on those days. The analyses demonstrated an overall association between air pollutant levels and mortality in both Taipei and Hong Kong, though the association was generally stronger in Taipei. The study suggests that there may be increased mortality associated with each city's current air pollution levels.