Abstract
[Background]Exposure to ozone(O3)is closely associated with an increased risk of mortality in the population,but this association exhibits regional heterogeneity,and relevant research in northern and central-western China is limited.Hohhot,as a typical city in the northern and western region,has seen a significant upward trend in O3 concentrations(an increase of 17.9 μg·m-3 in 2020 compared to 2016).Studies targeting this region can fill the regional research gap.
[Objective]To evaluate the health effects of ground-level O3 exposure on resident mortality in Hohhot from 2018 to 2023.
[Methods]Air quality,meteorological,and mortality data in Hohhot from 2018 to 2023 were collected.A time-series analysis based on Quasi-Poisson generalized additive model(GAM)was employed,controlling for meteorological factors,day-of-week effects,and holiday effects,to assess the impact of O3 on non-accidental mortality,mortality from circulatory system diseases(CSD),and mortality from respiratory system diseases(RSD).
[Results]From 2018 to 2023,the non-accidental,CSD,and RSD mortalities in Hohhot amounted to 89721,47394,and 11378 cases,re-spectively.The daily maximum 8-hour average O3 concentration(O3-8 h)was 90.00 μg·m-3.According to the Class I limit(100 μg·m-3)of GB 3095-2012 Ambient Air Quality Standard,the annual average number of days exceeding the standard was 144 d.For single-day lag effects,O3 had the strongest health impact on non-accidental mortality and CSD mortality on the current day(lag0),with effect sizes of 0.78％(95％CI:0.33％,1.24％)and 1.10％(95％CI:0.50％,1.71％),respectively.The strongest impact on RSD mortality occurred on the second day(lag2),with an effect size of 1.61％(95％CI:0.61％,2.62％).The subgroup analyses showed that for every 10 μg·m-3 increase in O3-8 h concentration,the risk of non-accidental mortality in females increased by 0.70％(95％CI:0.01％,1.41％);for CSD mortality,the risk in males and individuals aged≥65 years increased by 0.73％(95％CI:0.01％,1.47％)and 0.76％(95％CI:0.13％,1.39％),respectively.During the warm season,statistically significant risks were observed for non-accidental,CSD,and RSD mortalities,with increases of 1.07％(95％CI:0.54％,1.60％),1.31％(95％CI:0.59％,2.04％),and 2.27％(95％CI:1.07％,3.49％),respectively.In the two-pollutant models incor-porating sulfur dioxide(SO2),nitrogen dioxide(NO2),carbon monoxide(CO),particulate matter with an aerodynamic diameter of 10 mi-crometers or less(PM10),and fine particulate matter(PM2.5),the effect estimates(excess risk)of O3 remained stable and statistically sig-nificant(P<0.05),indicating model robustness.
[Conclusion]Ground-level O3 exposure in Hohhot increases mortalities due to non-accidental causes,CSD,and RSD,with more pronounced effects during the warm season.Females and individuals aged≥65 years may be susceptible populations.Therefore,relevant authorities should prioritize the potential health risks of O3 exposure,particularly to vulnerable groups,and promote targeted prevention and control strategies.关键词
空气污染/臭氧/死亡/时间序列分析/非意外总死亡/循环系统疾病/呼吸系统疾病Key words
air pollution/ozone/mortality/time-series analysis/non-accidental mortality/circulatory system diseases/respiratory system diseases分类
预防医学
