A new study out of Denmark found that cell phone use likely has no link to a certain key type of brain tumor.
The study, published in the American Journal of Epidemiology, found that people who had used cell phones for 11 to 15 years were no more likely to develop acoustic neuroma, a noncancerous brain tumor, than people with less excessive or no use of cell phones.
The study is key because of its focus on acoustic neuroma, the type of brain tumor that typically grows in the area of the brain that absorbs most of the radioactive waves of cell phones.
“Of interest is that acoustic neuromas grow in the area of the brain where greater energy emitted from the cellphones is absorbed, compared to other areas of the brain,” Dr. Joachim Schuz, who is with the World Health Organization’s International Agency for Research on Cancer (IARC) and led the new study, told Reuters.
Since mobile-device use did not prompt growth of the acoustic neuroma brain tumor, it can be inferred that it is less likely that cell phones beget tumorous growth in the brain. The study, for example, showed that while the majority of Danish people hold their cell phones on the right side of their heads, the participants were no more likely to grow a tumor on that side.
The study looked at 3 million Danish adults. Of the sample, 8,000 had been diagnosed with acoustic neuroma between 1998 and 2006. Those who used cell phones for 11 years or more showed no greater tendency toward acoustic neuroma. In addition, those who had been diagnosed with the brain tumor did not appear to have quicker-than-expected growth of their tumors.
While the study provides a bit of evidence to the contrary, it’s still a long ways from saying cell phones are harmless to the human brain. For one, 11 years of cell phone use is still a relatively short time. Acoustic neuromas develop slowly in many cases, and can sometimes take several decades to form. Cell phone use for most of the population began in the 1990s, which means the study worked under a constrained observational time period.
And of course, there are other types of brain tumors, many of which are cancerous.
The World Health Organization issued a statement in May saying that cell phones are “possibly carcinogenic.” This classification came after an extensive literature review revealed that the devices were linked to glioma, a cancerous type of brain tumor.
The study found that among the heaviest users of mobile phones–those who reported average usage of at least 30 minutes a day for a period of 10 years–were 40 percent more likely to have glioma.