The effects of Sulphur dioxide on acute mortality and years of life lost are modified by temperature in Chengdu, China.
The effect modification of meteorological factors on the association between ambient Sulphur dioxide (SO2) and mortality is critical for designing intervention policy. Existing studies did not result in consistent conclusions on the effect modification, and Years of life lost (YLLs) was rarely used as a health impact indicator to examine the modifying effect. This study aims to estimate the mean air temperature and relative humidity modification effects on the impact of SO2on daily mortality and YLLs in Chengdu, China. Mortality, YLLs, air pollution and meteorological data were collected for 2011-2014. Three analytical approaches based on generalized additive models (GAMs) were used, including bivariate response surface model, product term model, and stratification model. We found that the effects of SO2on mortality and YLLs depended on temperature at various lags, but did not depend on relative humidity. SO2exhibited larger adverse effects on mortality in high temperature level (22.8-29.4°C) days than in low temperature level (-0.3-9.3°C) days, with a 10μg/m3increment in SO2, non-accidental death increased by 0.8% (0.001, 0.015)at low temperature level, but increased by 1.4% (0.005, 0.024) at high temperature level. On the contrary, SO2showed greater adverse effects on YLLs in low temperature days than in high temperature days, with a 10μg/m3increment in SO2, non-accidental YLL increased by 40.580 (31.478, 49.682) at high temperature level, but increased by -2.703 (-14.668, 9.261) at low temperature level. We concluded that the effect of SO2on mortality and YLLs may depend on temperature in Chengdu, China. Our results highlight the importance of considering the interaction between SO2and temperature on health outcomes in future research. Also, policy makers should enhance the emission control of SO2in extreme temperature days in Chengdu.
Department of Epidemiology and Health Statistics, West China School of Public Health, Sichuan University, Chengdu 610041, Sichuan, China.
Fei
F
Chen
Department of Epidemiology and Health Statistics, West China School of Public Health, Sichuan University, Chengdu 610041, Sichuan, China.
Zhijiao
Z
Qiao
Department of Epidemiology and Health Statistics, West China School of Public Health, Sichuan University, Chengdu 610041, Sichuan, China.
Zhiwei
Z
Fan
Department of Epidemiology and Health Statistics, West China School of Public Health, Sichuan University, Chengdu 610041, Sichuan, China.
Qulu
Q
Zheng
Department of Epidemiology and Health Statistics, West China School of Public Health, Sichuan University, Chengdu 610041, Sichuan, China.
Yunyun
Y
Wu
Department of Epidemiology and Health Statistics, West China School of Public Health, Sichuan University, Chengdu 610041, Sichuan, China.
Meixia
M
Zhang
Department of Epidemiology and Health Statistics, West China School of Public Health, Sichuan University, Chengdu 610041, Sichuan, China.
Yan
Y
Cui
Sichuan Centre for Disease Control and Prevention, Chengdu 610041, Sichuan, China.
Ying
Y
Deng
Sichuan Environmental Monitoring Centre, Chengdu 610041, Sichuan, China.
Bin
B
Luo
Sichuan Environmental Monitoring Centre, Chengdu 610041, Sichuan, China.
Wei
W
Zhang
Sichuan Centre for Disease Control and Prevention, Chengdu 610041, Sichuan, China.
Kui
K
Ji
Institute of New Energy and Low-Carbon Technology, Sichuan University, Chengdu, Sichuan, China.
Xue
X
Qiao
Department of Epidemiology and Health Statistics, West China School of Public Health, Sichuan University, Chengdu 610041, Sichuan, China. Electronic address: zhaoxing731@gmail.com.
Xing
X
Zhao
Department of Epidemiology and Health Statistics, West China School of Public Health, Sichuan University, Chengdu 610041, Sichuan, China. Electronic address: lixiaosong1101@126.com.
Xiaosong
X
Li
D000393:Air Pollutants / Q000009:adverse effects*; D000397:Air Pollution; D002681:China; D006801:Humans; D009026:Mortality; D012621:Seasons; D013458:Sulfur Dioxide / Q000009:adverse effects*; D013696:Temperature
D000393:Air Pollutants; D013458:Sulfur Dioxide
Meteorological factors; Modification; Mortality; Sulphur dioxide; Years of life lost