Association between Air Pollution and Lung Function Growth in Southern California Children

TLDR

Lung‑function growth over four years in three Southern California child cohorts was modeled as a function of average ambient air‑pollutant exposure. Exposure to PM10, PM2.5, NO₂, and inorganic acid vapor was linked to significant reductions in lung‑function growth—up to 3.4 % in FEV₁ and 5 % in MMEF over four years—while ozone had no effect, and deficits were larger for children spending more time outdoors, indicating that current ambient concentrations of these pollutants negatively affect child lung development.

Abstract

Average growth of lung function over a 4-yr period, in three cohorts of southern California children who were in the fourth, seventh, or tenth grade in 1993, was modeled as a function of average exposure to ambient air pollutants. In the fourth-grade cohort, significant deficits in growth of lung function (FEV1, FVC, maximal midexpiratory flow [MMEF], and FEF75) were associated with exposure to particles with aerodynamic diameter less than 10 μ m (PM10), PM2.5, PM10–PM2.5, NO2, and inorganic acid vapor (p < 0.05). No significant associations were observed with ozone. The estimated growth rate for children in the most polluted of the communities as compared with the least polluted was predicted to result in a cumulative reduction of 3.4% in FEV1 and 5.0% in MMEF over the 4-yr study period. The estimated deficits were generally larger for children spending more time outdoors. In the seventh- and tenth-grade cohorts, the estimated pollutant effects were also negative for most lung function measures, but sample sizes were lower in these groups and none achieved statistical significance. The results suggest that significant negative effects on lung function growth in children occur at current ambient concentrations of particles, NO2, and inorganic acid vapor.