Objective: To explore acute effects of SO(2) and NO(2) on mortality in the six cities of China.
Methods: Surveillance data on daily air quality, meteorology and the cause of death were collected from January 1, 2007 to December 31, 2009 in Beijing, Tianjin, Xi'an, Shanghai, Guangzhou and Wuhan. Generalized additive model was used to explore the relationship between the daily average concentration of SO(2) and NO(2) and daily mortality, after adjusting the effects of long-term and seasonal trend and weather conditions.
Results: In Beijing, Tianjin, Xi'an, Shanghai, Guangzhou and Wuhan, the daily average concentration of SO(2) and NO(2) were in the range of 39.8-59.5 µg/m(3) and 41.4-60.1 µg/m(3) respectively; the daily mortality for non-accidental were 174.5, 101.4, 27.7, 108.4, 50.6, 17.8, cardiovascular were 86.9, 53.3, 12.8, 34.8, 16.3, 8.1 and respiratory were 18.3, 8.6, 2.6, 18.6, 9.0, 1.8 respectively. The daily average concentration of SO(2) were negatively correlated with daily average temperature in Beijing, Tianjin, Xi'an and Wuhan (the correlation coefficients were -0.66, -0.73, -0.67 and -0.39 respectively, P<0.05). The daily average concentration of SO(2) were negativeiy correlated with relative humidity in Tianjin, Shanghai and Wuhan (the correlation coefficients were -0.26, -0.46 and -0.28 respectively, P<0.05). The daily average concentration of NO(2) were negative correlated with daily average temperature in Beijing, Tianjin, Xi'an and Wuhan (the correlation coefficients were -0.27, -0.49, -0.45 and -0.38 respectively, P<0.05). When the day concentration of SO(2) increased every 10 µg/m(3), the non-accidental mortality in Tianjin and Wuhan raised 0.44%(95%CI: 0.11%-0.78%) and 0.96%(95%CI: 0.22%-1.72%) respectively. When the 1 day-lag concentration of SO(2) increased every 10 µg/m(3), the non-accidental mortality in Shanghai, Guangzhou and Wuhan raised 0.28% (95% CI: 0.02%-0.54% ), 0.41% (95% CI: 0.04%-0.79% ) and 1.14% (95% CI: 0.44%-1.84%) respectively. When the day and 1 day-lag concentration of SO(2) increased every 10 µg/m(3), the non-accidental mortality and the cardiovascular mortality at the six cities scale raised 0.40% (95% CI: 0.13%-0.67%) and 0.48% (95% CI: 0.11%-0.85%) respectively. When the day concentration of NO2 increased every 10 µg/m(3), the non-accidental mortality in Beijing, Tianjin, Shanghai, Guangzhou and Wuhan raised 0.60% (95% CI: 0.26%-0.95%), 0.96% (95% CI: 0.29%-1.64%), 0.43% (95% CI: 0.09%-0.78%), 1.17%(95%CI: 0.69%-1.66%) and 1.23%(95%CI: 0.19%-2.28%) respectively; the cardiovascular mortality in Beijing, Tianjin, Xi'an, Guangzhou and Wuhan raised 0.83% (95% CI: 0.34%-1.32%), 1.09% (95% CI: 0.25%-1.94%), 1.98% (95% CI: 0.00%-4.01%), 1.52% (95% CI: 0.70%-2.36%) and 2.04% (95% CI: 0.54%-3.56%) respectively. When the 1 day-lag concentration of NO(2) increased every 10 µg/m(3), the non-accidental mortality in Guangzhou and Wuhan raised 0.97% (95% CI: 0.49%-1.46%) and 1.67% (95% CI: 0.66%-2.70%)respectively; the cardiovascular mortality in Guangzhou and Wuhan raised 1.06% (95% CI: 0.24%-1.89%)and 2.42% (95% CI: 0.97%-3.89%) respectively. When the day and 1 day-lag concentration of NO(2) increased every 10 µg/m(3), the non-accidental mortality and the cardiovascular mortality at the six cities scale raised 0.81% (95% CI: 0.35%-1.28%), 1.03% (95% CI: 0.40%-1.66%) respectively.
Conclusion: Exposure to SO(2) and NO(2) was significantly associated with daily non-accidental morality and cardiovascular morality at the multi-city scale in China.