中国三城市臭氧对大气颗粒物与日死亡率关系的效应修饰作用

Modification effects of ozone on the relationship between PM_(10) and daily mortality in three cities,China

目的探讨臭氧（O3）是否对可吸入颗粒物（PM10）与居民日死亡率的关系存在效应修饰作用。方法收集北京、上海和苏州三城市2001—2008年每日居民死亡、大气污染和气象数据。按每日O3的污染水平,在各城市将O3的浓度分为低（≤第5百分位数）、中（第5到95百分位数）、高（〉第95百分位数）三层。在各层运用时间序列方法中的广义相加模型定量分析PM10与日死亡率的关系。采用Meta分析中的随机效应合并各层的PM10效应。结果北京、上海和苏州地区PM10所导致的每日非意外、心血管疾病和呼吸系统疾病死亡率均随着O3浓度的上升而增加。经Meta分析合并得到,当O3水平为＂低＂时,当日和前一日平均（lag 01）PM10浓度每升高10μg/m^3,每日非意外死亡率、心血管疾病死亡率和呼吸系统疾病死亡率分别降低0.47%（95%CI-0.74%-1.67%）、0.36%（95%CI-0.59%-1.31%）和0.69%（95%CI-0.52%-1.90%）;当O3水平为＂中＂时,分别升高0.45%（95%CI0.26%-0.63%）、0.16%（95%CI-2.26%-1.95%）和0.57%（95%CI 0.13%-1.02%）;当O3水平为＂高＂时,分别升高0.82%（95%CI 0.24%-1.39%）、0.37%（95%CI 0.07%-0.66%）和1.13%（95%CI-0.67%-2.92%）。结论北京、上海和苏州三个城市中O3浓度升高可促进PM10对日死亡率的影响。

Objective To estimate the modification effects of ozone on the relationship between PM10 and daily mortality. Methods Daily total non-accidental,cardiovascular and respiratory motality data in Beijing,Shanghai and Suzhou from 2001 to2008 were collected from the Center for Disease Control and Prevention of each city. The concentration of PM10 and ozone and other Meteorology data during the study period were abtained from the national air quality monitoring network. A generalized additive model（ GAM） were used to estimate the acute effects of air pollution on daily mortality in the three cities. The time-series method were applied to analyze the association between air pollution and daily mortality. In order to analyze the interaction effect between PM10 and ozone,ozone were stratified into three levels（ ≤ 5%,as low,from 5%- 95%,asmoderate, 〉95%,as high） and then analyzed the effect of PM10. A Meta analysis was used to describe the effect of PM10 in all the cities. Results With the increment of ozone,PM10 corresponded to an increase of total,cardiovascular and respiratory mortality in Beijing,Shanghai and Suzhou. The result of the Meta analyses showed that on the days of ＂low ＂ ozone,a 10 μg / m^3 increment in PM10 corresponded to a 0. 47%（ 95% CI- 0. 74%,1. 67%） decrease in total mortality,0. 36%（ 95% CI- 0. 59%,1. 31%）decrease in cardiovascular mortality,and 0. 69%（ 95% CI- 0. 52%,1. 90%） decrease in respiratory mortality. When it was moderate,the increment was 0. 45%（ 95% CI0. 26%,0. 63%）,0. 16%（ 95% CI- 2. 26%,1. 95%） and 0. 57%（ 95% CI 0. 13%,1. 02%）. The increment was 0. 82%（ 95% CI 0. 24%,1. 39%）,0. 37%（ 95% CI0. 07%,0. 66%） and 1. 13%（ 95% CI- 0. 67%,2. 92%） while theozone was high.Conclusion Ozone could modify the effect of PM10 on the daily mortality.