My cell phone is broken and, as I haven’t had time to get a new one, I had a phone-free day today. A new study in the Journal of the American Medical Association (JAMA) suggests that we all might want to think twice about using our cell phones too much.
The JAMA study has found that less than an hour of cell phone usage is linked to an increase in activity in the parts of the brain that are closest to the phone antenna. But, scientists caution, whether this increased brain activity is harmful has yet to be determined.
Led by Dr. Nora D. Volkow, director of the National Institute on Drug Abuse, researchers from the National Institutes of Health asked 47 participants to undergo positron emission tomography, or PET, scans, which is used to measure brain glucose metabolism, a marker of brain activity. The research was conducted in 2009.
Each participant underwent two 50-minute scans with a cell phone fitted on each ear. During one scan, the cellphones were not turned on on; during the second scan, the cell phone on the right ear was activated to receive a call from a recorded message (the sound on the phone was turned off, to avoid auditory stimulation). Says the New York Times in a review of the study:
Whether the phone was on or off did not affect the overall metabolism of the brain, but the scans did show a 7 percent increase in activity in the part of the brain closest to the antenna. The finding was highly statistically significant, the researchers said. The researchers said that the activity was unlikely to be associated with heat from the phone because it occurred near the antenna rather than where the phone touched the head.
The JAMA study is the ‘first and largest to document’ that even the weak electromagnetic signals from cell phones—which have been previously thought to be ‘benign’—can change brain activity. While it does not consider health concerns such as brain tumors (which a few observational studies have linked to heavy cell phone usage) and cancer, the study is likely to ‘reignite a debate’ about the safety of cellphones.
Unfortunately this particular study does not enlighten us in terms of whether this is detrimental or if it could even be beneficial,” Dr. Volkow said. “It just tells us that even though these are weak signals, the human brain is activated by them.”…Most major medical groups, including the American Cancer Society, the National Cancer Institute and the Food and Drug Administration, have said the existing data on cellphones and health has been reassuring, particularly a major European study released last year by the World Health Organization that found no increased risk of rare brain tumors among cellphone users.
Nonetheless, as the New York Times says, some doctors, including the former director of the University of Pittsburgh Cancer Center and some well-known neurosurgeons, have urged people to use headsets as a precaution. As University of Washington bioengineering professor Henry C. Lai writes in an editorial accompanying the JAMA study:
“The bottom line is that it adds to the concern that cellphone use could be a health hazard….Everybody is worried about brain cancer and the jury is still out on that question. There are actually quite a lot of studies showing cellphone radiation associated with other events, like sleep disturbances. But people have not been paying a lot of attention to these other types of studies.”
And I do have to say that, study or not, I’m getting a new phone tomorrow. 21st century parenting is pretty nigh impossible without a cell phone, to stay in touch with my son’s teachers and school and with my husband. One of my relatives gave me a Bluetooth device for the holidays and maybe I ought to think of using it?
Photo by compujeramey.