Residence Near Power Lines and Risk of Childhood Leukemia in Two Northern Italy Municipalities

Abstract

ISEE-0265 Background and Objective: Some epidemiological studies suggest an association between electromagnetic fields exposure, such as that induced by residence near high-voltage power lines, and childhood leukemia, but null results have also been yielded and the possibility of bias induced by unmeasured confounders has been suggested. Methods: We identified the corridors along the high-voltage power lines in the municipalities of Modena and Reggio Emilia, northern Italy, with estimated magnetic fields exposure cutoffs of 0.1, 0.2 and 0.4 μT. We identified all cases of leukemia diagnosed in children (age 0–13) residing in these two municipalities during the 1986–2006 period through a nation-wide hospital-based registry. As a control group we randomly selected four residents for each case, matched for year of birth, sex and municipality of residence. We collected information about historical residence and parental education for all study subjects. We included this information in a GIS database and calculated the risk of childhood leukemia associated with residence for at least 6 months in the exposed area. Results: Among the 47 cases and 188 controls included in the study, only 1 case and 2 controls had a historical residence in the exposed areas. The risk of leukemia associated with antecedent residence in the area with exposure exceeding 0.1 μT was 2.0 (4.16 in the analysis adjusted for parental education), but this estimate was statistically unstable; its 95% confidence interval being 0.2–22.1. Conclusion: The number of exposed children in this study was too low to allow firm conclusions, suggesting the need to substantially increase the study population. Though on the basis of these results an excess risk of leukemia among children exposed to electromagnetic fields from high-voltage power lines cannot be ruled out, the possibility of no association must also be considered.