Fact Or Fiction? Cell Phones Can
Cause Brain Cancer
Journalist: Melinda Wenner
November 21, 2008
This summer, Ronald Herberman, director of the University of Pittsburgh Cancer Institute, sent a memo
to staffers warning them to limit their cell phone use and to use
hands-free sets in the wake of "growing evidence that we should reduce
exposure" to cell phone radiation. Among the possible consequences: an
increased risk of brain cancer.
Five months later, a top official at the National Cancer Institute
(NCI) told a congressional panel that published scientific data
indicates cell phones are safe.
So what's the deal? Do cell phones cause cancer—or not?
It depends on whom you ask: Herberman, Robert Hoover, director of NCI's
Epidemiology and Biostatistics Program, and other health officials
recently clashed during a hearing before the House Subcommittee on
Domestic Policy held to determine whether mobile phones are safe.
"Long term and frequent use of cell phones which
receive and emit radio frequency may be associated with an increased
risk of brain tumors," Herberman told lawmakers. "I find the old adage
'better to be safe than sorry' to be very apt to this situation."
Hoover, on the other hand, insisted that the pervasive technology was
safe, testifying that "its effect on the body appears to be
insufficient to cause genetic damage."
The debate became so heated at one point that Rep. Dennis Kucinich
(D–Ohio), who called the hearing, snapped at Hoover for interrupting
David Carpenter, director of the Institute for Health and the
Environment at the University at Albany, State University of New York,
as he argued there was enough evidence to warrant more scrutiny and a
government warning of potential damage.
use non-ionizing radiation, which differs from the ionizing radiation
of x-rays and radioactive material in that it does not have enough
energy to knock around—or ionize—electrons or particles in atoms. Cell
phone radiation falls into the same band of non-ionizing radio frequency
as microwaves used to heat or cook food. But Jorn Olsen, chair of
epidemiology at the University of California, Los Angeles, School of
Public Health says that unlike microwaves, cell phones do not release enough radiation or energy to damage DNA or genetic material, which can lead to cancer.
Recent research suggests, however, that although short-term exposure is
harmless, long-term cell phone use may be a different story. Three
studies since 1999 indicate that people who have used cell phones for
more than a decade may have as much as three times greater risk of
developing brain tumors on the side of the head against which they most
often hold their phone—an argument for, at the least, shifting ears
regularly or, even better, using an earpiece or the speakerphone
feature while chatting.
"For people who've used their cell phones for more than 10 years and
who use their phone on the same side as the tumor, it appears there's
an association," Lawrie Challis, emeritus physics professor at the
University of Nottingham in England and former chairman of the U.K.'s
Mobile Telecommunications and Health Research program, told
Scientific American during a recent interview.
Worldwide, one in 29,000 men and one in 38,000 women on average develop
brain tumors each year, with people in industrial nations twice as
likely as those in developing countries to be diagnosed with one,
according to the World Health Organization's International Agency for
Research on Cancer (IARC) in Lyon, France. If cell phone use does, in
fact, triple the odds of getting cancer, these stats would suggest that
over 60 years a man's risk of developing a brain tumor from cell phone
use increases from 0.206 percent to 0.621 percent, and a woman's from
0.156 percent to 0.468 percent.
IARC in 2000 launched a study called Interphone, funded by the European
Union, the International Union against Cancer and other national and
local funding bodies. Interphone compared surveyed cell phone use in
6,420 people with brain tumors to that of 7,658 healthy people in 13
developed countries—Australia, Canada, Denmark, Finland, France,
Germany, Israel, Italy, Japan, New Zealand, Norway, Sweden and the
U.K.—to try to determine whether people with brain tumors had used
their cell phones more than healthy people, an association that might
suggest that cell phones caused the tumors.
The results are expected by the end of this year. "The interpretation
of the results is not simple because of a number of potential biases
which can affect the results," says project leader Elisabeth Cardis, a
professor at the Center for Research in Environmental Epidemiology at
the Barcelona Biomedical Research Park. "These analyses are complex and
have, unfortunately, taken much time." Among factors that might skew
the results: failure of participants—especially those with tumors—to
accurately recall exactly how long and often they talk on their cell
According to the U.S. Centers for Disease Control and Prevention (CDC),
the average time between first exposure to a cancer-causing agent and
clinical recognition of the disease is 15 to 20 years or longer—and
cell phone use in the U.S. has only been popular for about a decade.
(In 1996 there were 34 million U.S. cell phone users compared with more
than 200 million today, according to CTIA–The Wireless Association, a
Washington, D.C.–based cell phone industry group.)
Carpenter told the congressional panel that most of the studies that
have shown an increased risk are from Scandinavia, where cell phones
have been popular since the early 1990s. Herberman added that most of
the research showing cell phones are safe is based on surveys of
consumers who have used them for less than 10 years.
Despite a dearth of human studies, more than 400 experiments have been
done since the early 1970s to determine how cell phone radiation affects animals,
cells and DNA. They, too, have produced conflicting results. Some
suggest that cell phone radiation damages DNA and/or nerve cells,
others do not. At the hearing, Carpenter suggested that cell phones may
increase the brain's production of reactive forms of oxygen called free
radicals, which can interact with and damage DNA.
Contradictory findings could be a sign of poor study quality, according
to NCI expert Hoover. But Jerry Phillips, a biochemist who performed
cell phone research at U.S. Department of Veterans Affairs's Pettis VA
Medical Center in Loma Linda, Calif., in the 1990s, believes that
conflicting results are to be expected given the nature of the
radiation being scrutinized.
Phillips says, for instance, that sometimes the body will respond to
radiation by initiating a series of intrinsic repair mechanisms
designed to fix the harmful effects. In other words, the effects from
radiation exposure may be different in different people. And these varied responses
may help explain the contradictory results, says Phillips, who is now
director of the Science/Health Science Learning Center at the
University of Colorado at Colorado Springs.
There is plenty of anecdotal evidence out there claiming a link between
cell phone use and cancer: Keith Black, chairman of neurosurgery at
Cedars-Sinai Medical Center in Los Angeles, says that the brain cancer
(malignant glioma) that killed O. J. Simpson's attorney, Johnnie
Cochran, was the result of frequent cell phone use, based on the fact
that the tumor developed on the side of the head against which he held
his phone. And in May, a week after Massachusetts Sen. Edward Kennedy was
diagnosed with a glioma, The EMR Policy Institute, a Marshfield,
Vt.–based nonprofit organization that supports research on the effects
of electromagnetic radiation, released a statement linking his tumor to
heavy cell phone use. But the NCI maintains that there is no definitive evidence that cell phones increase cancer risk.
In other words, the verdict is still out. "We can't rule out the
possibility of risk," Nottingham's Challis says. "There hadn't been as
much work in this area as is now demanded."