Download Cell phones affect brain activity, study says – Study finds no evidence

Discussion/Action Item 1g
CEAC
April 7, 2011
Cell phones affect brain activity, study says - Study finds no evidence of tumors
or other consequences for health
SFGate, February 23, 2011
A 50-minute cell phone call causes a noticeable increase in brain activity in the area of the head
closest to the phone's antenna, a finding by government researchers that could reinforce concerns,
or at least raise new questions, about the long-term health effects of cell phones.
The study by the National Institutes of Health is one of the first, and the most prominent, to offer
scientific evidence that cell phones affect brain metabolism. Results were published in today's
issue of the Journal of the American Medical Association.
Scientists involved with the study said it's far too early to draw conclusions about whether
electromagnetic radiation emitted by cell phones can cause tumors - one major concern among
some scientists and doctors - or have any other negative health consequences. But their results
demonstrate a need for further research.
"Unfortunately, our findings do not enlighten in any way this controversy on whether cell phones
produce cancer. What they do say is that the human brain is sensitive to this electromagnetic
radiation," said Dr. Nora Volkow, a director with the National Institutes of Health and lead
researcher for the study. "Whether this electromagnetic radiation has any negative consequences,
that is something that needs to be properly evaluated."
Dozens of small studies on the topic have found some correlation between long-term cell phone
use and brain tumors, but most research has found no connection to cancers or any other diseases.
In response to the new study, the International Association for the Wireless Telecommunications
Industry noted that research so far has "overwhelmingly indicated" that cell phones and other
wireless devices are safe.
But some researchers and laypeople who worry about the widespread use of cell phones say the
majority of studies haven't been thorough enough, and it could be a decade or two before
industrialized nations see dramatic health consequences.
Joel Moskowitz, director of the Center for Family and Community Health at UC Berkeley, said
he's not convinced that cell phones are dangerous, but he is frustrated with the pervasive refusal
by many scientists to seriously consider the possibility. He hopes the latest study - and its
association with the National Institutes of Health and publication in one of the country's major
scientific journals - will give credibility to the need to look deeper.
"This study establishes that cell phones do indeed have biologic reactivity on the brain. The
(wireless) industry and scientific community seems reluctant to hear that," Moskowitz said. "I'm
hoping this study will force policymakers to take this issue much more seriously and begin to
encourage research in this area."
In the NIH study, which had 47 participants, cell phones were placed next to both ears while the
subjects underwent brain imaging using positron emission tomography (PET scans). Participants
were given an injection of glucose to measure brain activity; brain cells use glucose as a source
of energy.
Subjects were scanned twice, once with both cell phones turned off, and once with the right cell
phone turned on and connected to a call, but set on mute. Neither the participants nor the
researchers knew when the cell phones were off or on.
"Because the brain uses glucose when it's activated, we interpreted this to mean that the
electromagnetic waves were activating the cells," Volkow said. "This type of activation by itself
we don't expect to have harmful effects. The question that remains to be studied is could there be
long-term consequences from long-term stimulation."
Dr. Mitch Berger, chairman of the department of neurosurgery at UCSF, agreed that the study
demonstrates a need for further research. But he also noted that the effects on the brain weren't
especially worrying.
Brain metabolism simply means the neurons have been stimulated - a PET scan would show
similar readings if someone was asked to perform a simple task like conjugating a verb - and
there's no evidence that increased brain activity is damaging, even over a long period of time, he
said.
"It is a provocative study because it has shown that there is an alteration of brain metabolism.
But I'm not convinced in any way, shape or form that it means something," Berger said. "I don't
think you can extrapolate this to assume there's a health hazard here."
That said, he said he recognizes that almost everyone uses cell phones these days, and people are
naturally curious, or even worried, about the effects of that practice on their health. With that in
mind, he and other scientists, even many skeptics, recommend a simple solution: headsets.
"I don't think people should be panicked or change their usage," Berger said. "But putting
distance between the device and the side of your head is a reasonable, prudent strategy until we
see what happens 10 to 20 years from now."