This work establishes that cellphone activity does have a real effect on nearby brain cells. Even that was in doubt until this work.
Earlier work was of thestatistical kind and I found it to be at least suspect in terms of at least notcorrecting for the low level radiation effect in which the stimulation actuallyimproves later cancer statistics. We arestill on our own when it comes to heavy cell phone usage.
Yet I do know one heavy cellphone user who succumbed to brain cancer at the age of thirty with a decade ofheavy use. This is not good enough butthen I have also known a couple of other victims who succumbed before cellphone availability. It is not so rarethat one is unlikely to ever know a victim, unlike lung cancer in the absenceof tobacco.
We now have a measurable effectthat we certainly do not like and the take home for now is to use a headset andplace the phone elsewhere. There is noconvincing statistical evidence that problems are been generated to date that Iam aware of, but such information may well be a decade away if there is aproblem at all and who wants to find out the hard way.
On a more positive note, thisresult links nicely with the finding that cell phone usage is associated with ameasurable delay in the onset of Alzheimer’s in sensitive mice.
Cellphone Radiation Increases Brain Activity
By Dave Mosher
February 22, 2011
Radiation from a mobile phone call can make brain regions near thedevice burn more energy, according to a new study.
Cellphones emit ultra-high-frequency radio waves during calls and datatransfers, and some researchers have suspected this radiation — albeitinconclusively — of being linked to long-term health risks like brain cancer.The new brain-scan-based work, to be published Feb. 23 in the Journalof the American Medical Association, shows radiation emitted from acellphone’s antenna during a call makes nearby brain tissue use 7 percent moreenergy.
“We have no idea what this means yet or how it works,” saidneuroscientist NoraVolkow of the National Institutes of Health. “But this is the firstreliable study showing the brain is activated by exposure to cellphone radiofrequencies.”
More than 5 billion mobile devices may be in use worldwide today. Frombehavioral quirks to brain cancer, researchers have looked for any health risksassociated with cellphone radiation for years. Volkow said, however, that mostresearch has produced conflicting results.
“These studies used only 14 people, at most, and looked at brainactivity over brief time spans of about 60 seconds. A cellphone’s effect on thebrain is very weak, so you lose statistical power with small sample sizes anddurations,” said Volkow. “Our study had 47 usable subjects monitored over along time to get us significant data.”
Cancer epidemiologist GeoffreyKabat of the Albert Einstein College of Medicine said the work can’tand doesn’t offer any clinical predictions, but regarded it as the best to dateon cellphone radiation’s effects on the brain.
“It’s a really even-handed look at this problem, and it shows a smalleffect that scales with exposure,” said Kabat, author of the book Hyping HealthRisks.
Cellphones use ultra-high-frequency radio waves to connect withtelecommunications networks. Antennas within phones emit the waves and, whilethe strength tails off quickly as distance from the antenna increases, asizable chunk of it is beamed through the brain.
As a result, federal agencies require phone manufacturers to postinformation about how much radiation the body might absorb for each model,called its Specific Absorption Rate or SAR. Measured in watts per kilogram oftissue, it reveals how much radiation parts of the body are exposed to duringuse of a mobile device.
The simple cellphone used in Volkow’s study, a Samsung Knack phone popular in
, has a peak SAR in the head of justunder 1 watt per kilogram of tissue. The Phone 4 has a peak SAR in the head twice as high,while the sun’s average SAR can be 5 watts per kilogram during sunbathing. New York
Some studies have suggested a small yet significant link betweenlong-term cellphone SARs and certain brain cancers, including glioma andmeningioma, but most investigations have found no such links. To abolish anyuncertainty, the World Health Organization tasked a group of scientists toreview all known related research. Their 2010 Interphone report showed no substantial link withmobile phone use and incidence of brain cancers, and in fact found reducedrates for some types.
‘The effect is very small, but it’s still unnatural. Nature didn’tprepare our brains for this.’
Still, Volkow said, understanding close-up and long-term exposure tocellphone radiation is important.
“The state of knowledge is really speculative. No studies havedetermined mechanisms for what we have seen, or other effects such as increasedblood flow in the brain,” Volkow said. “I have spent hours on the phone with mysister every week, and have done it for years, so I would like to know ifthat’s harmful or not.”
Volkow and a team of researchers scanned the brains of 47 people with acellphone attached to each side of their head. One phone was turned off, whilethe other had an active call going for 50 minutes. It was muted to prevent theaudio from having effects on brain activity.
Twenty minutes into the call, clinicians injected a radioactive form ofsugar into each person, then began imaging their brains with a PositronEmission Topography machine. Over the course of 30 minutes, the sugar pooled inthe brain’s most active regions and revealed the energy use to the brainscanner.
Accounting for normal activity, the subjects showed about a 7 percentboost in sugar use on the side of the head where the active cellphone was.
Brain imaging physicist DardoTomasi of Brookhaven National Laboratory, who co-authored the study,said that’s several times less activity than visual brain regions show duringan engaging movie.
“The effect is very small, but it’s still unnatural. Nature didn’tprepare our brains for this,” Tomasi said.
Although the mechanism for the effect and its long-term consequencesaren’t known, Volkow said it’s cheap and worthwhile to take matters into yourown hands.
“You don’t have to wait around on us for the answers. Just use a wiredheadset or the speakerphone function,” she said. “That keeps the phone farenough away to make it an insignificant risk.”
Image: A bottom-of-the-brain view showing average use of radioactiveglucose in the brains of 47 subjects exposed to a 50-minute phone call on theright side of their head. (Nora Volkow/JAMA)