And heaven forbid anyone should carry a cell phone in a pocket or clipped to a belt. "You're just roasting your bone marrow," Davis said.
Although there are many large studies (industry funded studies) showing no connection between mobile phones and cancer, there are a few that do.
As Davis puts it, do you really want to play Russian roulette with your head?
But if you do buy the cellphones-cause-cancer argument, you have to figure out the best way to talk on a cell phone, seeing as how most of us can't live without them.
Should you use the wired headset that came with your phone? A Bluetooth earpiece?
Cell phones have been wildly popular for only a matter of years, and it can take at least a decade for cancers to show up.
Studies contradict each other, and scientists bicker: Some will tell you with great conviction that there's nothing to worry about.
Others will tell you with equal conviction that an epidemic of brain tumors may be just around the corner.
The cell phone industry itself says "the overwhelming majority of studies that have been published (and paid for by the industry) show that wireless phones do not pose a health risk."
Resarchers can agree that cell phones do emit radiation.
No one knows definitively whether it's enough to worry about.
Mobile phones meet federal safety limits, but if you're still worried, there are some simple steps you can take to lower your exposure to radiation.
1. Use the speakerphone
This was, without question, the favorite alternative of the experts I talked to. Nothing is near your head. "Hold it away from a minimum of a few inches. A foot or two is ideal," said Magda Havas, an associate professor with the Institute for Health Studies at Trent University in Ontario, Canada.
Every inch you can get away from your body, the radiation reduces very quickly.
"Hold it out two inches, and the radiation drops by a factor of four. Hold it out four inches, and it drops by a factor of 16," she says.
In other words, said Louis Slesin, editor of Microwave News, "every millimeter counts."
2. Use a wired headset with a ferrite bead
A ferrite bead is a clip you put on the wire of a headset. The concern is that the wire itself emits radiation into your ear. The bead is designed to absorb the radiation so you don't. They're inexpensive and available at stores or online.
These clips are a favorite of Slesin's. "It's the way to go," he said.
Another fan: Lawrie Challis, physicist and former chair of the Mobile Telecommunications and Health Research Programme, a government panel in Britain.
"They did tests at the University of York and found that under even the worst conditions, if you use a ferrite bead, you can't even measure the radiation coming off the wire. This common device kills the radiation."
Of course, if the phone is in your pocket or clipped to your belt, all bets are off, because the phone itself will be radiating into your body. So if you're worried about radiation, keep the phone as far away as possible, and Challis adds to do your best to make sure the wire isn't touching your body.
3. Use a Bluetooth earpiece
A Bluetooth earpiece still has radiation, but it's at least 100 times less than the radiation you get when you hold a cell phone to your head, Havas says.
Our experts were split on which was better: a Bluetooth headset or a wired one.
Israeli government recommendations issued this week specifically suggest a wire; Havas likes the Bluetooth. But even she says not to wear it when you're not talking; it still sends out a signal.
"Bluetooth is only whispering radiation into your ear. The problem is, some people wear it all the time," she says. "At the very least, switch it from ear to ear so you don't have too much exposure on one side."
Michael Foley, Ph.D., executive director of the Bluetooth Special Interest Group, says Bluetooth earpieces radiate 200 times less energy than cell phones. "There is no evidence that a Bluetooth headset has any adverse effects on its users," he said.
4. Use a "hollow tube" earpiece
It's just like a regular wired earpiece, except the last six inches or so - the part next to your ear - is a hollow tube. There's no wire under the plastic.
"You're getting the sound through the air. You're not dependent on radiofrequency waves," said Dr. David Carpenter, director of the Institute for Health and the Environment at the University of Albany.
Hollow tube earpieces can be purchased on several Web sites.
5. Get a phone with less radiation
Phone radiation is measured in specific absorption rate, or SAR. To look up the SAR for your phone, check this list on CNET.com.
You might think the experts mentioned above all use earpieces or a speakerphone. Not so. Several said they hold it right up to their heads because they use their cells so infrequently, they're not worried about radiation.
"I use it maybe once or twice a week, no more than 10 minutes," said Challis, the former head of the British committee that studied cell phones and radiation. "I use a land line whenever I can."
It's the exposure, day after day, year after year, that matters. As Challis, who's retired, puts it, "If I were younger, I'd take this much more seriously."