Abstract
BACKGROUND: Previous studies have focused on the effects of air pollution on lung function in children with respiratory diseases, and there is insufficient evidence on healthy children. This cross-sectional study therefore aimed to investigate the relationship between air pollutants and lung function in healthy children. METHODS: We collected lung function measurements between December 2016 and December 2020 from a total of 780 healthy children aged 7-11 years old in an elementary school in Jinan City. Air pollutant data, including particulate matter with an aerodynamic diameter ≤2.5 µm (PM(2.5)) and ≤10 µm (PM(10)), sulphur dioxide (SO(2)), nitrogen dioxide (NO(2)), carbon monoxide (CO) and ozone (O(3)), were collected from the nearest monitoring stations to the school. Multiple linear regression models were developed to assess the relationship between pollutants and children's lung function indices. RESULTS: Increasing pollutant concentrations were associated with decreases in forced vital capacity (FVC), forced expiratory volume in 1 second (FEV(1)), peak expiratory flow (PEF), forced expiratory flow at 25% (FEF(25)) and forced expiratory flow at 75% (FEF(75)). In addition, this effect had a lag effect and a cumulative lag effect, especially at lag 3 d, with significant decreases in FEV(1) and PEF. Specifically, for every 10 µg/m(3) increase in the concentrations of PM(2.5), PM(10), SO(2), NO(2), and CO, the FEV(1) decreased by 1.05 mL [95% confidence interval (CI): -2.02, -0.08], 1.18 mL (95% CI: -1.94, -0.42), 4.96 mL (95% CI: -8.08, -1.84), 4.94 mL (95% CI: -7.59, -2.28), and 0.11 mL (95% CI: -0.20, -0.01), respectively. For every 10 µg/m(3) increase in PM(10), SO(2), NO(2), and CO, PEF decreased by 3.80 mL (95% CI: -6.51, -1.08), 16.73 mL (95% CI: -27.83, -5.63), 17 mL (95% CI: -26.44, -7.55), and 0.39 mL (95% CI: -0.72, -0.05), respectively. Boys' lung function was more sensitive to pollutants than girls'. CONCLUSIONS: Short-term exposure to air pollutants is harmful to children's health and appropriate protective measures should be taken to minimize the adverse effects of air pollution on children's health.