Association between short-term exposure to ambient air pollution and daily mortality: a time-series study in Eastern China

Few studies were conducted to evaluate health effects of acute exposure to PM2.5 and daily mortality in Asian countries due to lack of large-scale PM2.5 monitoring data. We conducted a time-series study to examine the associations of short-term exposure to four common air pollutants (PM2.5, PM10, NO2, and SO2) and daily mortality in Ningbo, Zhejiang, China. We used generalized addictive model (GAM) to estimate relative risks (RRs) and 95% confidence intervals (CIs) for the association of these four air pollutants with daily mortality. The study included 9365 people in the 2-year study period from 2014 to 2015. SO2 were significantly associated with risk of NAD, RD, and CD mortality with RRs of 1.034 (95% CI 1.004, 1.064), 1.067 (95% CI 1.010, 1.127), and 1.049 (95% CI 1.001, 1.098), respectively.PM2.5 and PM10 were significantly associated with risk of death from NAD mortality in warm season. Similar associations were observed for PM10 (RR = 1.056, 95% CI 1.004, 1.111) and risk of CD mortality. The study provides further evidence that short-term exposure to PM2.5, PM10, NO2, and SO2 are associated with increased risk of daily mortality.