Kheifets L, et al. - A large records-based case–control study of childhood leukemia risk and exposure to magnetic fields from power lines in California, was conducted. Although consistent with previous findings of increased risk, this study itself did not provide clear evidence of risk associated with greater exposure to magnetic fields from power lines.

Methods

• 5,788 childhood leukemia cases (born in and diagnosed in California 1986–2008) matched to population-based controls on age and sex, were enrolled in this study.
• Magnetic fields were measured at birth addresses using geographic information systems, aerial imagery, historical information on load and phasing, and site visits.

Results

• A slight risk deficit in two intermediate exposure groups and a small excess risk in the highest exposure group (odds ratio of 1.50 (95% confidence interval [0.70, 3.23])) had been reported based on unconditional logistic regression controlling for age, sex, race/ethnicity, and socioeconomic status using subjects geocoded to a basic standard of accuracy.
• In addition, subgroup and sensitivity analyses as well as matched analyses gave similar results.
• This study revealed wide confidence intervals in all estimates.