Abstract:
Objectve As an eco-tourism island, Chongming Island has atracted much atenton on its air quality. In this study, we analyze the impact of air pollutant concentratons on outpatent visits in Chongming District of Shanghai, and provide a scientific basis for formulating air pollution preventon and control policies for the ecological island.
Methods We collected data on air polluton, meteorological factors, and daily outpatent visits registered in Shanghai Tenth People's Hospital Chongming Branch for all purposes, respiratory diseases, and circulatory diseases from 2014 to 2017. A generalized linear model was used to analyze the exposure-response relatonship between concentratons of selected air pollutants and outpatent visit volume. A 10 μg/m3 increase in selected air pollutants was used to compute the relatve risk (RR) and excess risk (ER) of daily outpatent visit volume.
Results During the study period, the daily average concentrations of PM2.5, O3, PM10, NO2, SO2, and CO were 38.6 μg/m3, 107.3 μg/m3, 48.8 μg/m3, 17.0 μg/m3, 9.2 μg/m3, and 0.4 mg/m3, respectvely; the unqualifed rates of PM2.5, O3, PM10, and NO2 were 10.17%, 9.28%, 1.77%, and 0.28%, respectvely, but SO2 and CO did not exceed the limits. The daily outpatent volumes for all purposes, respiratory diseases, and circulatory diseases were 1 393, 123, and 167 person-tmes, respectvely. For total outpatent visits, each 10 μg/m3 increase of PM2.5, PM10, NO2, SO2, and O3 elevated the outpatent volume (ER) by 0.17%, 0.16%, 0.60%, 1.39%, and 0.10%, respectvely. For respiratory outpatent visits, each 10 μg/m3 increase of PM2.5, PM10, NO2, SO2, and O3 elevated the outpatent volume by 0.38%, 0.26%, 0.98%, 1.61%, and 0.27%, respectvely. For circulatory outpatent visits, each 10 μg/m3 increase of PM2.5, PM10, NO2, SO2, and O3 elevated the outpatent volume by 0.27%, 0.19%, 0.83%, 1.45%, and 0.15%, respectvely. Five selected air pollutants, except CO, had different lag effects on the three categories of outpatent volume. The strongest lag effects of PM2.5 on total, respiratory, and circulatory disease outpatent visits were all on lag1; for PM10, on lag1, lag1, and lag3, respectvely; for NO2, on lag1, lag1, and lag2, respectvely; for SO2, all on lag3; for O3, on lag2, lag3, and lag2, respectvely.
Conclusion The increases of concentratons of selected air pollutants (PM2.5, PM10, NO2, SO2, and O3) would increase the outpatent visit volume of the hospital, and the related lag effects range from 1 to 3 days.