The effect of air pollution on hospital visits for respiratory symptoms in urban areas of Jinan

To evaluate the acute health effects of air pollution exposure, data for daily air quality and hospital visits for respiratory symptoms in the Licheng district of Jinan were collected from 2002 to 2005. After controlling for long term trends, the "day of the week"effect and confounding meteorological factors, a non-parametric generalized additive model (GAM) was adopted to analyze best fit lag days and the exposure-response relationship. Pollutants including PM10, SO2 and NO2 all have positive relationships with residents’ hospital visits for respiratory complaints. In single-pollutant models, the best fits for PM10 and NO2 were same day visit (lag0) and three days after (lag3), while a four day moving average (avg03) was most suitable for SO2. Particulate matter (PM10), SO2 and NO2 were associated with increased likelihood of hospital visits with every 10 μg/m3 increase of pollutant concentration. Relative risk (RR) was 1.004 for PM10, 1.015 for SO2, and 1.008 for NO2. Females were more susceptible than males to air pollution.