Interaction between ambient oxidizing pollutants and air temperature in relation to daily mortality among residents in Hohhot
- VernacularTitle:大气氧化性污染物与气温对呼和浩特市居民每日死亡影响的交互作用
- Author:
Shengjie QIN
1
;
Chengyao WANG
1
;
Fengxia HE
1
;
Rina SHA
1
;
Yuanyuan LIU
1
;
Hairong YANG
1
Author Information
- Publication Type:Investigation
- Keywords: ambient oxidizing pollutant; air temperature; circulatory disease mortality; respiratory disease mortality; interaction
- From: Journal of Environmental and Occupational Medicine 2026;43(9):1096-1103
- CountryChina
- Language:Chinese
- Abstract: Background The health effects of environmental exposures are often characterized by complex interactions. However, evidence on the joint health effects of ambient oxidizing pollutants and air temperature in the cold regions of Northern China remains limited. Objective To examine the independent and interactive effects of atmospheric oxidizing pollutants and air temperature on daily mortality among residents of Hohhot. Methods Daily data on air quality, meteorological factors, and cause-specific mortality in Hohhot from 2018 to2023 were collected. A quasi-Poisson generalized additive model (GAM) combined with a distributed lag non-linear model (DLNM) was used to examine the effects of ambient oxidant pollutants [ozone (O3), nitrogen dioxide (NO2), and total oxidant (Oₓ)] and air temperature on daily circulatory and respiratory mortality. Potential interactions between oxidizing pollutants and temperature were evaluated using bivariate exposure–response surface models and quantified through stratified analyses. Results For each 10 μg·m−3 increase in O3, OX, and NO2 concentrations, the strongest associations with circulatory disease mortality occurred at lag1, with excess risks (ERs) of 1.10% (95%CI: 0.50%, 1.71%), 1.84% (95%CI: 0.94%, 2.75%), and 1.49% (95%CI: 0.36%, 2.62%), respectively. The strongest associations of O3 and OX with respiratory disease mortality were observed at lag2, with ERs of 1.61% (95%CI: 0.61%, 2.62%) and 2.61% (95%CI: 1.61%, 3.62%), respectively. NO2 showed the strongest cumulative association with respiratory disease mortality at lag02, with an ER of 3.22% (95%CI: 1.24%, 5.25%). High temperature exhibited immediate or short-term effects, while low temperature showed lagged effects. The exposure–response relationships between temperature and mortality risks for respiratory circulatory diseases were U-shaped. Positive additive interactions were observed between high temperature and high concentrations of O3 and OX. For the joint exposure to high temperature and high O3, the relative excess risks due to interaction (RERIs) for circulatory and respiratory disease mortality were 0.131 (95%CI: 0.086, 0.176) and 0.279 (95%CI: 0.198, 0.360), respectively. For the joint exposure to high temperature and high OX, the corresponding RERI values were 0.080 (95%CI: 0.038, 0.123) and 0.154 (95%CI: 0.074, 0.234), respectively. In contrast, high temperature and high NO2 concentration exhibited antagonistic or attenuating interactions. Conclusion Ambient oxidizing pollutants, high temperature, and low temperature are independently associated with increased circulatory and respiratory disease mortality. High temperature combined with high concentrations of O3 or OX exerts positive additive interactions, with the respiratory system showing particular vulnerability. The mortality risks associated with NO2 are more pronounced under low temperature conditions, whereas its interaction with high temperature appear antagonistic, suggesting a temperature-dependent risk-modifying effect.
