Industrial air pollution and children's respiratory health: A natural experiment in Călăraşi

Abstract

BACKGROUND: In 1993-1997, we described a high incidence of wheezing in children living near the iron, steel, and coke factory of Călăraşi (Romania). In 1998, the factory was closed. OBJECTIVE: To investigate the influence of closing the factory on the incidence of wheezing in children living near the factory. METHODS: We used this natural experiment to compare wheezing occurrence in children below age 2 in an area near the factory and in a village 10 km from the factory (Roseţi). We studied three birth cohorts: those 2 years old before the closing of the factory (group 1), those born before the closing and returning 2 after the closing (group 2), those born after the closing (group 3). RESULTS: The relative risk (95% CI) of having at least one episode of wheezing during the first life-year was 0.51 (0.30-0.85) in group 3 versus group 1, and 0.95 (0.64-1.40) for group 2 versus group 1. After adjusting for possible confounders, the incidence dropped in Călăraşi (odds ratio [OR] 0.38, 95% CI 0.19-0.76), while it increased in Roseţi (OR 8.36, 95% CI 1.84-38.0). Results for the 2-year incidence were similar. CONCLUSION: Industrial air pollution by the factory was the main risk factor for wheezing during the first life-years of the children of Călăraşi. Closing the factory resulted in a significant decrease in wheezing incidence rates, which still remained higher than in a nearby village.