A group of Danish researchers say they have found no link between the use of cell phones and a type of benign brain tumors most likely to be the result of cancerous electronic device emissions.
In the study, which was published online last month in the American Journal of Epidemiology, researchers correlated cell phone use with the rate of development of vestibular schwannoma tumors on the right side of the brain, where most people hold their cell phone since most humans are right-handed.
Researchers used nationwide cohort studies encompassing data on the mobile phone use of 2.9 million Danes. They found no increase in the expected number of vestibular schwannoma brain tumors among men, and actually found less tumors than expected among women. When vestibular schwannoma tumors did occur, there was no propensity for them to develop on the right side of the head over the left.
The scientists concluded that there was no evidence of cell phones causing vestibular schwannoma brain tumors. They also criticized some previous studies which did find a correlation, indicating the studies relied on flawed cell phone use reporting data.
The study’s findings were released just weeks after the World Health Organization (WHO) reclassified radiofrequency electromagnetic fields emitted by wireless phones as a possible carcinogen. There are more than 5 billion cell phone subscriptions across the planet, WHO warned, and they are heavily used by children and young adults. That number is steadily growing.
In the U.S. in recent years the National Cancer Institute (NCI) has reported that scientific evidence about the risk or safety of cell phones is conflicting and inconsistent, and that no conclusion could be made.
According to NCI, cellular telephones emit radiofrequency (RF) energy. RF energy is a form of non-ionizing electromagnetic radiation. Ionizing electromagnetic radiation, such as that emitted by x-ray machines, is known to cause cancer at high levels, but it is unknown whether non-ionizing electromagnetic radiation like RF energy has the same effect. The NCI says that studies so far seem to indicate that the amount of RF emitted by cell phone hand units is too low to result in tissue heating or raise body temperature, but there is not enough evidence to declare it completely harmless either.