Acute Effects of Air Pollution on Lung Function of Schoolchildren during Heating Season in Jinan, China

Objective To investigate the acute effects of increased air pollution after central heating on the lung function of schoolchildren.

Methods A field investigation was conducted in a primary school in the severely air-polluted area of Jinan, Shandong province, China, during 2014 to 2017. One class each was randomly selected from grade three to grade five during heating season of every year using the stratified cluster random sampling method, and all students in the sample grades were tested for height, weight, and lung function. The authors compared the changes in pollutant concentrations (PM_2.5, PM₁₀, SO₂, NO₂, and CO) and children's lung function indices before and after central heating, and analyzed the association between the pollutants and lung function using a multiple linear regression model.

Results The concentrations of PM_2.5, PM₁₀, SO₂, NO₂, and CO significantly increased after central heating in Jinan (P < 0.05). A total of 1 194 lung function tests of 484 schoolchildren showed that there were significant decreases after heating in peak expiratory flow (PEF) (t=3.19, P < 0.01), forced expiratory flow at 75% (FEF75) (t=2.28, P < 0.05), and forced expiratory flow at 25% (t=2.89, P < 0.01). For every 10 μg/m³ increase in PM_2.5, there was an associated 9.28 (4.37~14.18) mL decrease in forced vital capacity (Lag2), an associated 5.31(2.64~7.98) mL decrease in forced expiratory volume in FEV₁ (Lag1), an associated 36.58(16.66~56.50) mL/s decrease in PEF (Lag0), an associated 6.09(2.07~10.11) mL/s decrease in FEF75 (Lag1), and an associated 56.27(34.32~78.22) mL/s decrease in FEF75 (Lag0).

Conclusion During heating season in Jinan, air pollution deteriorates and has acute effects on the lung function of healthy schoolchildren.