Effects of Long-Term Exposure to Traffic-Related Air Pollution on Lung Function in Children

Abstract

Lung function in early life has been shown to be an important predictor for peak lung function in adults and later decline. Reduced lung function per se is associated with increased morbidity and mortality. With this review, we aim to summarize the current epidemiological evidence on the effect of traffic-related air pollution on lung function in children and adolescents. We focus in particular on time windows of exposure, small airway involvement, and vulnerable sub-groups in the population. Findings from studies published to date support the notion that exposure over the entire childhood age range seems to be of importance for lung function development. We could not find any conclusive data to support evidence of sup-group effects considering gender, sensitization status, and asthma status, although a possibly stronger effect may be present for children with asthma. The long-term effects into adulthood of exposure to air pollution during childhood remains unknown, but current studies suggest that these deficits may be propagated into later life. In addition, further research on the effect of exposure on small airway function is warranted.

Keywords: Adolescence; Asthma; Cohort; Epidemiology; Sensitization; Small airways; Spirometry.

Fig. 1

A schematic illustration of effects on lung function from long-term traffic-related air pollution (TRAP) exposure. The Y-axis corresponds to lung function and the X-axis corresponds to time (age). The blue line illustrates normal lung function growth and decline, with a maximum in young adulthood. The dark red line illustrates lung function growth slightly less than normal due to exposure of traffic-air pollution. The long-term effect of air pollution exposure during childhood remains largely unknown