It seems a bit of a no-brainer (no pun intended) to be concerned about putting a microwave transmitter right next to one's head for long periods of time. There are known deleterious effects, cancer notwithstanding, of such exposure at higher intensities. And I don't know of anyone arguing against caution regarding radiation leakage from microwave ovens.
Unsettled research has doctors hung up on recent advisory
By Suzanne Bohan
Cell phones are back on the hook as possible health hazards, leaving a puzzled public wondering what to make of years of flip-flopping over medical dangers of the ubiquitous gadgets.
Headlines in 2007 proclaimed that a large study from Denmark
exonerated cell phones from any connection to brain tumors -- a nagging worry linked to the low-energy radio waves passing to and from the devices. And previous news stories on mobile phone health studies reported either hints of risk or, in many cases, an absence of danger.
But a precaution issued last week by an academic cancer institute advising against heavy cell phone use triggered a fresh round of alarm and concern over the long-term effects of that electromagnetic radiation, a precaution repeated worldwide by the media.
The advisory included particularly strong advice for protecting children from cell phone radio waves, due to children's small size, rapidly growing bodies and brains, and potential for long-term
exposure. Even cordless phones are included in the statement, since they also emit radio waves.
"Our motive is making prevention the cure for cancer," Devra Davis, director of the University of Pittsburgh's Center for Environmental Oncology, said in a telephone interview.
rays, are strong enough to potentially damage DNA, which may trigger cancer formation. But radio waves from cell phones aren't strong enough to create that kind of cellular havoc. So thus far, no plausible biological explanation exists for how cell phones could cause tumor formation.
But cell phone radiation can heat up tissue, potentially damaging it. And Kheifets said that it's possible that new mechanisms for cancer development from low-energy radio waves could be discovered.
"Just because we don't understand it doesn't mean it isn't true," she said. "We didn't understand how cigarette smoke caused lung cancer for a long, long time."
The chief problem with the state of research on the potential health hazards of phone radio waves rests in the design of studies thus far conducted, Kheifets explained.
"All the studies have methodology problems. They have lots of limitations," she said.
A review of the health effects of radio waves, published in Environmental Health Perspectives, which she co-authored, put it more bluntly: "Most of the studies suffer from severe imprecision."
To date, there have been about 40 significant studies on the health effects of cell phones, Kheifets said. They typically include too few people to accurately catch an increase in often-rare brain cancers, for example, or they rely on memory of cell phone use years earlier, which is prone to error. Another significant flaw, Kheifets said, is that none of the studies ran long enough to monitor the emergence of typically slow-growing brain tumors.
But the most egregious oversight, in her view, is the paucity of research on cell phone use and children's health.
"Given the amount of youth using cell phones, a lot of things have not been looked at," Kheifets said.
A study in the July 7 issue of Physics in Medicine and Biology, Kheifets said, reported that the brains of children under the age of eight absorb twice as much radio waves from cell phones compared with adults.
The National Cancer Institute, adopting a middle-of-the-road stance, noted in a prepared statement that while studies haven't shown a consistent link between cell phone use and cancer, "additional research is needed before firm conclusions can be drawn."
The U.S. Food and Drug Administration concurred, noting that "research has produced conflicting results." In its "Cell Phone Facts" report, the agency added: "There is no proof, however, that wireless phones are absolutely safe."
The FDA also noted that three large studies have been published since 2000 on the link between cell phone use and brain cancers -- such as glioma, meningioma or acoustic neuroma, as well as leukemia and other cancers -- and none found an association. But since the research lasted no longer than three years, "none of the studies can answer questions about long-term exposure," according to the FDA
Much more support for independent research on health effects of mobile phone radio waves is needed, emphasized Davis of the University of Pittsburgh.
"The issue is this: We have something that everybody is exposed to," she said. "So why don't we make a more serious effort to study it?"
As a start in that effort, Davis said that her colleague, Herberman, is requesting cell phone records from companies to analyze whether long-term users are at greater risk of health problems such as brain and neck tumors.
Fisher, the brain tumor expert with Lucile Packard Children's Hospital, however, emphasized the rarity with which these kinds of cancers typically emerge.
"Even if we thought there was a very, very tiny risk (with cell phone use), the risks are miniscule already," he said.
And there are far more immediate dangers from cell phone use, he said, such as increasing the risk of injury by using them during other activities, or other pressing health issues to focus on, like rising obesity rates in youth.
Still, given that more than 2 billion people worldwide are estimated to use cell phones, even a tiny health hazard from electromagnetic radiation could add up, said Kheifets.
"We're dealing with a very, very large exposure," she said. "Even a