Ever since mobile phones became available in the early 1980s, there has been some concern about their use causing negative health effects.  The thought behind this was that low level exposure to radiofrequency electromagnetic fields, such as that emitted when using cellular phones, could lead to the development of brain tumors. A review of this possibility in the late 1990s led to the initiation of an international study on the relationship between cell phone use and brain tumors.

Known as the “INTERPHONE” study, its results were posted on June 17, 2010 – prior to the publication of the paper in the International Journal of Epidemiology.* This study is the largest case-control study done to date on cell phones and brain tumors and  included the largest number of cell phone users with at least 10 years of exposure. Also, it included the greatest cumulative hours of cell phone use of any prior study.

The study looked specifically at the occurrence of two types of brain tumors: gliomas and meningiomas. You may already know that gliomas are malignant and can be highly aggressive. Meningiomas, on the other hand, are not malignant, but can cause bad effects by virtue of growing and impinging on structures in the brain. 

The study found that there was no increased occurrence of meningiomas associated with regular cell phone use. For gliomas, the study found that there was no overall risk either, but also found was that there might be an increased risk only in those people who: 1) had the highest amount of time of cell phone usage; and 2)had gliomas located in the temporal lobe of their brain (located on either side of the head); and 3) reported regular cell phone usage on the same side as the glioma was found.  However, the researchers believe this finding about gliomas to be inconclusive since there were possible sources of error in the study that still needed to be analyzed.

Bottom line: the researchers believe that the possible causation of gliomas by longterm use of mobile phones requires further study.

What does all this mean for you? That the jury is still out on whether cell phones are definitely unsafe.  However, the fact that the study showed that those people who seemed to be at greatest risk for a glioma were those who had the highest level of exposure to the electromagnetic fields makes sense.

Could this study be an early warning? Medical literature is loaded with early studies, such as this, that showed a trend, but that were not statistically significant – or definitive – that a behavior caused a negative health outcome. Like cigarette smoking and lung cancer.  And we know how that turned out.

What should or shouldn’t you do? Well, you shouldn’t worry. But to be absolutely safe, you should consider either limiting the time you spend on your cell phone (that’s a tough one) OR start using an ear piece, at least until further studies are out. I’m headed out now to get my “Blue Tooth”.

*Posted: 06/17/2010; International Journal of Epidemiology. 2010;39(3):675-694. © 2010 Oxford University Press