Background

Pulmonary function is known to be affected by acute and subacute exposure to ambient air pollution. However, the impacts of lifetime exposure to air pollution on the pulmonary function of children have been inconsistent. The present study investigated the impact of lifetime residential exposure to intermediate levels of air pollution on the pulmonary function of schoolchildren.

Methods

In 2011, a survey of children aged 6–15 years was conducted in 44 schools in Taiwan. Atopic history, residential history, and environmental factors were recorded. Spirograms were obtained from a random sample of children without asthma. A total of 535 girls and 481 boys without a history of asthma were enrolled. Lifetime residential exposure to air pollutants, including particulate matter with an aerodynamic diameter less than 10 μm (PM₁₀), ozone (O₃), sulfur dioxide (SO₂), nitrogen dioxide (NO₂), and carbon monoxide (CO), was estimated using the kriging method, based on monitored data from the Taiwan Environmental Protection Administration. Multiple linear regression was used to analyze the association between lifetime air pollution exposure and pulmonary function, after adjustment for potential confounders and recent exposure.

Results

After adjustment for 7-day average air pollutant levels, a 10 μg/m³ increase in PM₁₀ was related to reductions in the forced expiratory volume in 1 s (−2.00%; 95% confidence interval [CI] −3.09% to −0.90%), forced vital capacity (−1.86%; CI: −2.96% to −0.75%), and maximal midexpiratory flow (−2.28%; CI: −4.04% to −0.51%). These associations were independent of the other pollutants.

Conclusion

Lifetime exposure to 25–85 μg/m³ of PM₁₀ has negative impacts on the pulmonary function of children.