Magnetic fields exposure and childhood leukemia risk: a meta-analysis based on 11,699 cases and 13,194 controls

To observe the association between childhood leukemia and magnetic field exposure.

The literature was searched by PubMed, ProQuest, Web of Science (SCI) and Medline databases during 1997-2013. Heterogeneity in several studies was weighted by I-squared value. Publication bias was tested by funnel plot and Egger's test. Odds ratio (OR) and 95% CI were used to evaluate the association strength. The statistical analyses in present study were carried out by STATA software package (version 12.0, College Station, TX).

A total of 11,699 cases and 13,194 controls in 9 studies were stratified by different exposure cut-off points. On condition of the reference <0.1 μT, statistical association between magnetic field intensity ≥0.4 μT and childhood leukemia was exhibited (for total leukemia: OR = 1.57, 95% CI = 1.03-2.40; for acute lymphocytic leukemia: OR=2.43, 95% CI = 1.30-4.55). On condition of the reference level of <0.2 μT, the positive association between magnetic field intensity ≥0.2 μT and childhood leukemia was found (OR = 1.31, 95% CI = 1.06-1.61).

The result in this meta-analysis indicated that magnetic field exposure level may be associated with childhood leukemia.