When it comes to the potential human health effects of cell phone use, certainly, you might end up with a crick in your neck if you text excessively, or even break your neck or the neck of someone you may hit if you text while driving. On the other hand, think of the countless lives that have been saved on the road, because people are now able to so quickly phone in emergencies.
But what about cancer? Since the turn of the century, there have been studies suggesting there is up to double the risk of brain tumors with long-term cell phone use on the side of your head you use to talk. That’s important, because the radiation only really penetrates up to a couple of inches into your brain. Views from the back of the head and the top of the head show why you might develop cancer on one side of the head over the other.
Since it’s such a local effect, you can see why there are recommendations for using the speakerphone function or a hands-free headset, which can reduce brain exposure by a factor of 100 or more—and this includes the option of using Bluetooth headsets. This may be particularly important in children, who have thinner skulls.
Cell phone radiation isn’t like nuclear radiation, though. It doesn’t damage DNA directly, like gamma rays from an atomic bomb. However, it does appear to be able to damage DNA indirectly by generating free radicals. In a review study published in 2015 in Electromagnetic Biology and Medicine, out of 100 studies that looked at this, 93 confirmed there were oxidative effects from the kind of low-intensity radiofrequency radiation that comes out of cell phones. Another review published in Pathophysiology in 2009 looked at 101 studies, of which 49 found that this oxidative stress translated into DNA damage, detecting signs of genotoxicity, which is damage to our genes, DNA, or chromosomes. A smaller number of studies, 42, did not find a genotoxic effect.
But a lot of those studies were done in petri dishes or in lab animals. I’m less interested in whether Mickey or Minnie is at risk than I am concerned about brain tumors in people. When it comes to people, some population studies found increased cancer risk, but other studies did not.
