A new study has investigated the effects of radiofrequency electromagnetic fields (RF-EMF) and intermediate frequency electromagnetic fields (IF-EMF) and found no clear association with brain tumours[i]. This is the largest study of brain tumours and occupational high-frequency EMF exposure to-date[ii].
In 2011, the International Agency for Research on Cancer (IARC) classified RF-EMF as ‘possibly carcinogenic to humans’. However, evidence in human studies for an association between occupational exposure to RF-EMF and cancer was judged to be inadequate, partly due to limitations with exposure assessment.
The new study examined the relationship between RF-EMF and IF-EMF and the risk of two types of brain tumour, known as glioma and meningioma. Approximately 4,000 brain cancer patients and over 5,000 controls, who participated in the INTEROCC study, were selected.
The participants provided information about their work activities. Literature documenting exposure from different sources was used to estimate cumulative exposure to EMFs in the course of employment. Occupational sectors where employees are exposed to EMFs include work with/near radars or telecommunication antennas; medical diagnosis and treatment; and work with microwave drying ovens.
Data analysis found no clear evidence for a positive association between cumulative exposure to RF-EMF or IF-EMF and a risk of developing glioma or meningioma. Most relationships that were investigated showed no association whatsoever. The largest odds ratios were found in those exposed within the most recent time window (1-4 years prior to diagnosis) and in participants exposed to the highest 10% of EMF. However, neither odds ratio was statistically significant.
A limitation of this study was that only 10% of study participants were exposed to RF-EMF and only 1% were exposed to IF-EMF.
The researchers concluded that there was no clear association between EMF and glioma or meningioma. However, results in participants with recent exposure to EMFs suggested a potential link with brain tumour promotion/progression and should be investigated further.
Indeed, lead author of the study, Javier Vila, explained:
‘Although we did not find a positive association, the fact that we observed indication of an increased risk in the group with most recent radiofrequency exposure deserves further investigation. We also need to investigate possible interactions with other frequencies, and with chemicals’.[iii]
[i] Vila, J. et al. Occupational exposure to high-frequency electromagnetic fields and brain tumor risk in the INTEROCC study: An individualized assessment approach. Environment International 119, 353–365 (2018). https://www.sciencedirect.com/science/article/pii/S016041201830196X (Accessed 2 August 2018)
[ii] Exposure to high-frequency electromagnetic fields at work not associated with brain tumours. Science Daily 31 July 2018. https://www.sciencedaily.com/releases/2018/07/180731092046.htm (Accessed 2 August 2018)