Authored By:
Pedersen C, Johansen C, Schüz J, Olsen JH, Raaschou-Nielsen OThis case-control study investigated the association between exposure to extremely low frequency (ELF) magnetic fields (MF) and three types of childhood cancers (leukaemia, central nervous system tumour and malignant lymphoma). This study was an extension of an older study to include recent cases. A total of 1570 cases and 4341 controls were included in the present study (covering 1987-2003), for a grand total of 3277 cases and 9129 controls for the combined period of 1968-2003. The analyses on the three cancers combined revealed that for the group exposed to elevated level of MF (defined as 0.4 microtesla, µT or greater) the odds ratio (OR) was 0.88 (95% confidence interval, 95% CI = 0.32-2.42) in the present study and 1.63 (95% CI = 0.77-3.46) in the combined period. The authors concluded that the increased risk associated with elevated MF exposure found previously OR 5.72 (CI 1.40-23.36) could not be confirmed based on the present study.
Published In:
Br J Cancer 2015; 113 (9): 1370 - 1374The study by Pederson et al includes only very small numbers of cases and controls who are exposed to elevated MF; there were only 11 cases and 19 controls that were exposed to elevated MF in the combined period of 35 years. The exposure to ELF MF in the study was assessed using the distance of the subject’s residence to electrical supply infrastructure. This method of exposure assessment may have misclassified the exposure status of the subjects in the study.
