Effect of photochemical smog associated with synoptic weather patterns on cardiovascular and respiratory hospital admissions in metropolitan Taipei.

This study focuses on the relationship between photochemical smog (PS) (hourly ozone conc. >100 ppb), PS-related diseases, and the synoptic weather patterns during 2005-2009 in metropolitan Taipei. The results show that compared to respiratory ailments (ICD code 460-519) and asthma (ICD code 493), cardiovascular ailments (ICD code 390-459) were more clearly influenced by PS events. On the PS event day, the number of admissions of babies, children, and adults increased by 0.04 [95% CI 0.01-0.06], 0.03 [95% CI 0.00-0.07], and 1.12 [95% CI 0.36-1.89] (P < 0.05), respectively. The investigation showed that more than 70% of the PS events were associated primarily with the peripheral circulation of typhoons, Pacific pressure, and discrete Pacific pressure. PS events are a threat to public health. To avoid the ill effects of air pollution, residents should be informed about the daily weather patterns and air quality.