by Justina Hurley
A possible association between heavy mobile phone use and brain tumours.
A study reported in the British Journal of Occupational and Environmental Medicine has found a possible association between heavy mobile phone use and brain tumours.
The study, called CERENAT, was a multicenter case-control study carried out in four areas in France between 2004 – 2006.
A total of 253 gliomas (tumours that start in the glial cells in the brain), 194 meningiomas (tumours from the meninges, the membranous layers surrounding the central nervous system) and 892 matched controls selected from the local electoral rolls were analysed.
No association with brain tumours was observed when comparing regular mobile phone users with non-users. However, the positive association was statistically significant in the heaviest users when considering life-long cumulative duration and number of calls.
Risks were higher for gliomas, temporal tumours, occupational and urban mobile phone use.
The full study is available here: Mobile phone use and brain tumours in the CERENAT case-control study
How could cell phones/mobile phones be harmful?
Cell phones emit radiofrequency energy (radio waves), a form of non-ionizing radiation. Non ionising radiation is the type that is found in microwave ovens, radar etc.
Tissues nearest to where the phone is held can absorb this energy. The energy manifests as heat and the known biological effect of radiofrequency energy is heating, for example when microwave ovens heat food.
The question to ask with cell phone use is not ‘do cell phones cause cancer’, but rather does holding a device with the ability to heat biological tissue, such as brain cells, in a localised area for a long period of time create an injury that could ultimately leave that area susceptible to cancer?
According to the National Cancer Institute:
Radiofrequency exposure from cell phone use does cause heating; however, it is not sufficient to measurably increase body temperature. A recent study showed that when people used a cell phone for 50 minutes, brain tissues on the same side of the head as the phone’s antenna metabolized more glucose than did tissues on the opposite side of the brain. The researchers noted that the results are preliminary, and possible health outcomes from this increase in glucose metabolism are still unknown.
Taking this and the CERENAT study together it seems likely that anything that ultimately mildly ‘cooks’ the cells nearest to it is not something that you necessarily want to hold right next to your head!
It may be that while non ionising radiation does not alter DNA, that this heating effect and it’s effect on glucose metabolism creates a good environment for cancer to form. Cancer cells are highly metabolic and rapidly synthesise glucose, that is the principle on which PET Scanning is based after all.
In November 2011, Singer Sheryl Crow was diagnosed with a meningioma. It was benign and she is fine. However she publicly speculated that her brain tumour may have been caused by her extensive cell phone use. This created controversy at the time but as she developed a meningioma and was a heavy phone user that places her very much in the CERENAT profile, so her theory may be correct.
But don’t panic!!! There are ways to use your phone safely and sensibly:
- Put it in Airplane mode at night and when playing games. The only time your phone is not sending bursts of non-ionising radiation is when it is off or in airplane mode.
- Try to text more than phone
- Don’t hold the phone to your ear or near your head when on a call. Use the hands free function instead and place it near you in such a way that so no part of your body is in contact with it during a call when it is emitting most energy.
- Only let children play games in airplane mode – this is also a great way to stop accidental paid in game add-ons!!
- If you have to make a lot of calls and hands free is not always an option then at least use a head set.