Acute effects of air pollution on pulmonary function and exhaled nitric oxide in children in Shanghai

Abstract

ObjectiveTo investigate the acute effects of compound air pollution on children’s respiratory function.MethodsUsing panel group study design， 223 students in five classes of grade 4 from two primary schools （a， b） in Xuhui and Hongkou districts of Shanghai were randomly selected to measure pulmonary function and exhaled nitric oxide （FeNO）. The first three tests were carried out from May to June in 2020， and the fourth test was carried out from September to December in 2021. At the same time， the daily and hourly mean values of PM2.5， PM10， SO2， NO2， O3 and CO was collected from the nearby air quality monitoring points of the two schools during the same period ， as well as meteorological monitoring data （temperature， humidity， wind speed and atmospheric pressure）. The linear mixed effect model was used to analyze the effects of air pollution on pulmonary function and respiratory inflammation in the summer.ResultsThe results of single pollutant model showed that PM2.5， PM10， SO2 and NO2 were positively correlated with FeNO， and the effect was reflected in lag0， lag1 and lag3 （P<0.05）. PM2.5， PM10 and NO2 were negatively correlated with the changes of lung function FEF25%， FEF50%， FEF75%， FeF25%-75%， PEF， FVC， FEV1 and FEV1/FVC， and the effect was reflected in lag0 to lag3 days （P<0.05）. The results of the dual pollutant model showed that the concentration changes of SO2 and NO2 were significantly correlated with the decrease of FEV1 when combined with O3 or PM2.5 （P<0.01）， and the concentration changes of PM2.5 was significantly correlated with the increase of FeNO when O3， SO2 and NO2 were combined respectively （P<0.01）. The effects of the dual pollutant model were greater than the effect of PM2.5 single pollutant model.ConclusionThe health effects of different air pollutants on children’s respiratory tract function indexes in summer are different. The combined effects of two pollutants on the lung function of children increased to different degrees. Although air pollution is light in summer， it still has an impact on children’s respiratory tract function index and inflammation index， and the combined effect of dual pollutants is more significant than that of single pollutant.

Keywords

• air pollution
• primary school student
• pulmonary function
• exhaled nitric oxide