Korean J Prev Med.  2001 Nov;34(4):316-322.

Summertime Heat Waves and Ozone : an Interaction on Cardiopulmonary Mortality? - Based on the 1994 Heat Wave in Korea -

• Sung J
• Kim H
• Cho SH

Abstract

OBJECTIVES
To explore the possible effect of an interaction between summertime heat waves and ozone on cardiopulmonary mortality during the 1994 heat wave in Korea.
METHODS
The unusually hot summer of 1994 in Korea was defined as the heat wave in this study. We examined the associations of air pollutants with daily cardiopulmonary deaths between 1991-1995, considering the product term of the heat wave and each pollutant, weather and time trends.
RESULTS
During the heat wave, while temperatures were uniformly higher than those of other summers, the within-heat-wave difference in mortality paralleled that in the regional ozone levels. In terms of the influence of the heat wave, the results of ozone were different to those of total suspended particles (TSP) and sulfur dioxide (SO2). The ozone association (relative risk (RR) =1.036; 95% confidence interval (CI) = 1.018-1.054) was observed only under heat wave conditions, while the TSP (RR =1.006, 95% CI = 0.999-1.012) and the SO2 (RR =1.018, 95% CI = 1.011-1.024) associations were found under normal weather conditions (per interquartile increase of each pollutant; results of three pollutants model). The ozone association under heat wave was attributable to the statistical interaction between the heat wave and ozone.
CONCLUSIONS
These results support the possibility of a biological synergy between the heat wave and ozone, one that is not evident between the heat wave and other major pollutants like particles or SO2.

Keyword

Ozone; Heat wave; Cardiopulmonary mortality; Air pollution

MeSH Terms

Air Pollutants
Air Pollution
Hot Temperature*
Infrared Rays*
Korea*
Mortality*
Ozone*
Sulfur Dioxide
Weather
Air Pollutants
Ozone
Sulfur Dioxide