The Influence of Large-Scale Airborne Particle Decline and Traffic-Related Exposure on Children’s Lung Function

Between 1991 and 2000, ambient air pollution in East Germany changed to resemble West German pollution levels: The concentration of total suspended particles (TSPs) decreased on a broad scale while traffic increased. During that time, we analyzed total lung capacity (TLC) and airway resistance (R(aw)) of East and West German children. We tested children 5–7 years of age (n = 2,574) with cooperation-independent body plethysmography in repeated cross sections. We used random-effect models to determine the mutually adjusted association between lung function and short-term and chronic particle exposure and its interaction with living near a busy road. Annual averages of TSPs declined from 77 to 44 μg/m(3); averages on the day of investigation declined from 133 to 30 μg/m(3). Differences in lung function between East and West German children vanished during the investigation time. The association of TSPs with R(aw) and TLC was stronger in children living > 50 m away from busy roads. East German children from this group had an R(aw) 2.5% higher [95% confidence interval (CI), 0.0–5.1%] per 40-μg/m(3) increase of daily TSP averages. TLC decreased by 6.2% (95% CI, 0.04–11.6%) per 40-μg/m(3) increase in annual mean TSPs, and this effect was equally pronounced in East and West Germany. TSP exposure decreased on a broad scale between 1991 and 2000. Lower concentrations of TSPs were associated with better measures of lung function in 6-year-old children. For children living near busy roads, this effect was diminished.