Article publication date
December 2024
ARPANSA review date
May 2025
Summary
This cohort study examined rates of cancers among people who lived in apartments and were exposed to extremely low frequency electromagnetic fields (ELF EMFs) from electricity transformers. The exposed population was categorized into three groups: most exposed (individuals living in ground and first-floor apartments adjacent to the transformer room, n = 8,840), unexposed (individuals living on higher floors, n = 179,285), and partially exposed (individuals living on the ground and first floors but not adjacent to the transformer room, n = 52,599 Cancer diagnosis was based on entry in the Finnish Cancer Registry. The study compared the number of cancers that occurred in the apartment buildings to the average numbers that occur based on the Finish Cancer Registry. The study found no association between ELF EMF exposure and cancer incidence when all cancers were examined together (all site cancers standardized incidence ratio (SIR) 1.01, 95% confidence interval (CI) 0.93-1.09). However, when cancers were examined individually, a statistically significant association was observed for the exposed group with digestive organs cancers (SIR 1.23 95% CI 1.03-1.46) [overall], and more specifically with gallbladder cancer (SIR 3.92, 95% CI 1.44-8.69), and small intestine cancer (SIR 2.67, 95% CI 1.08-5.56). Overall, the study reported no elevated risk of cancers associated with the ELF EMF exposure due to living near an electrical transformer; however, it showed an elevated risk of digestive organ cancers due to the ELF EMF exposure.
Published in
Occup Environ Med
Link to study
Commentary by ARPANSA
The study found that the overall risk of cancer was not associated with living near an electrical transformer. However, it found an association with digestive organ cancers, including small intestine and gallbladder cancer. There were a few notable limitations for this study that challenges the observed associations for risk. For example, the study did not take into account any confounding factors such as socioeconomic status or the main risk factors for digestive organ cancers such as eating habits (Zhang et al, 2021). These limitations make the interpretation of the study findings difficult as these unaccounted known risk factors could be the cause of the statistically significant association with digestive organ cancers.
ELF EMF exposure was based on distance to a transformer not measurements and this could result in exposure misclassification. As shown in the paper by Okokon et al, (2014) there is a large spread in the exposure observed in apartments adjacent to transformers. This means that the apartments may not be areas with a higher magnetic field and the cancers observed in the study have nothing to do with exposure to ELF EMF.
Some epidemiological studies observing outcomes from exposure to ELF EMF greater than 0.3 or 0.4 µT have shown an association with childhood leukaemia (SCENIHR 2015). However, this association has not been established by consistent scientific evidence. The epidemiological evidence for this association is weakened by various methodological problems such as potential selection bias, misclassification and confounding. Furthermore, it is not supported by laboratory or animal studies and no credible theoretical mechanism has been proposed on how ELF EMF exposure could cause cancer (Karipidis et al, 2024). Overall, the scientific evidence does not establish that exposure to magnetic fields in the everyday environment is a hazard to human health.
It is ARPANSA’s assessment that based on current research, there is no substantiated scientific evidence that exposure to ELF electric fields below the international guidelines is a health hazard. More information about exposure to ELF EMF can be found on the ARPANSA factsheet Electricity and health | ARPANSA.
