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The safety of cellphones has been called
into question, again. This time the scientific community is
paying very close attention.
Last summer neurosurgeon
Leif Salford and colleagues at Lund University in Sweden
published data showing for the first time an unambiguous link
between microwave radiation emitted by GSM mobile phones (the
most common type worldwide) and brain damage in rats. If
Salford's results are confirmed by follow-up studies in the
works at research facilities worldwide, including one run by
the U.S. Air Force, the data could have serious implications
for the one billion?plus people glued to their cellphones.
The findings have re-ignited a longstanding debate
among scientists and cellphone manufacturers over cellphone
safety.
Many of the hundreds of studies performed
during the past decade suggest cellphone use may cause a host
of adverse effects, including headaches and memory loss. Other
studies, however, have shown no such effects, and no
scientific consensus exists about the effect of long-term,
low-level radiation on the brain and other organs. A
comprehensive $12 million federal investigation of cellphone
safety is currently under way but will take at least five
years to complete.
Meanwhile, the research world is
scrambling to replicate Salford's surprising results. His team
exposed 32 rats to 2 hours of microwave radiation from GSM
cellphones. Researchers attached the phones to the sides of
the rats' small cages using coaxial cables -- allowing for
intermittent direct exposure -- and varied the intensity of
radiation in each treatment group to reflect the range of
exposures a human cellphone user might experience over the
same time period. Fifty days after the 2-hour exposure, the
rat brains showed significant blood vessel leakage, as well as
areas of shrunken, damaged neurons. The higher the radiation
exposure level, the more damage was apparent. The controls, by
contrast, showed little to no damage. If human brains are
similarly affected, Salford says, the damage could produce
measurable, long-term mental deficits.
The cellphone
industry so far has been quick to dismiss the data, saying
emissions from current mobiles fall well within the range of
radiation levels the FCC deems safe (body-tissue absorption
rates of under 1.6 watts per kilogram). "Expert reviews of
studies done over the past 30 years have found no reason to
believe that there are any health hazards whatsoever," says
Mays Swicord, scientific director of Motorola's
Electromagnetic Energy Programs. Dr. Marvin Ziskin, chair of
the Institute of Electrical and Electronics Engineers'
Committee on Man and Radiation, is similarly skeptical. "The
levels of radiation they used seem way too low to be producing
the kinds of effects they're claiming."
Salford is the
first to admit that it's too early to draw any conclusions,
but contends the unusual results deserve a closer look. "The
cellphone is a marvelous invention; it has probably saved
thousands of lives," he says. "But governments and suppliers
should be supporting more autonomous research." Meanwhile,
Salford advises users to invest in hands-free headsets to
reduce radiation exposure to the brain.
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