기후변화와 대기오염이 환경관련 질환에 미치는 영향

Abstract

Climate Change and Air Pollution Effects on Environmentally Related Disease - Interactive Effects of Temperature and Ozone on Environmentally Related Disease - Patterns of air pollutions are driven by weather. Particularly, ozone are correlated with temperature. Along with this, both temperature and ozone are associated with human health. Therefore, an examination of potential additive effects or confounding effects between temperature and ozone is necessary. Several studies have been suggested that apparent ozone effects could be to heat or an interaction between temperature and ozone could be plausible. In this study, we examined whether temperature modifies the associations between ozone and health outcomes. We used a time-series analysis to examine the association between ozone or temperature and health outcomes. The data consisted of daily time series of mortality counts, hospitalization count for asthma, weather variables, and air pollutants from January 1999 to December 2008 in Seoul, Busan, Daegu, and Incheon. We used a Poission generalized additive model(GAM) to fit a bivariate response surface in order to examine patterns of interaction of both ozone and temperature on health outcomes. Temperature showed significant effects on summer mortality and hospitalization for asthma. Daily variations in ozone within the range currently occurring in Korea were significantly associated with an increased risk of death and asthma hospitalization. To quantitatively estimate the ozone-health outcome associations across different temperature levels, we separately fitted the stratification model. When temperature was high (above the threshold temperature), for a 10ppb increase in ozone concentration, the contributions of mortality were 2.22% (95% confidence interval [CI]: 1.27~3.17%), 2.00% (95% CI: 1.01~2.99%), 3.32% (95% CI: 1.86~4.75%), and 1.81% (95% CI: 0.40~3.21%) in Seoul, Busan, Daegu, and Incheon, respectively. When temperature was low (below the threshold temperature), for a 10ppb increase in ozone concentration, the contributions of mortality were 0.51% (95% CI: 0.11~0.92%), 1.18% (95% CI: 0.27~2.08%), 0.77% (95% CI: -0.22~1.75%), and 0.48% (95% CI: -0.58~1.53%) in Seoul, Busan, Daegu, and Incheon, respectively. Therefore, ozone effects were 1.7~9.7 times higher at high levels of temperature than at a low level of temperature. In analysis for hospitalization of asthma, the results suggested that the broad pattern of higher ozone effects in high level of temperature remained. Also, temperature effects, ozone effects, and ozone-temperature interactions were higher for elderly people and cardiovascular mortality, which is consistent with previous studies identifying elderly people as more sensitive to air pollution and temperature. The results of this study show that temperature modified ozone-mortality associations. We recommend that public health strategies to minimize adverse health impact of heat and ozone should be considered within control and prevention of air pollution and weather-related health impacts.