BehindTheMedspeak: Can cellphones damage a growing child's brain?

Sir William Stewart, chairman of Britain's National Radiological Protection Board, said he had more doubts now than he did five years ago about the safety of cellphones when used by children.

The Wall Street Journal, in a story last Friday, quoted Stewart as saying that making cellphones available to children ages 3 to 8 was "unjustified."

Wrote reporters David Pringle and Peter Grant, "He [Stewart] added that children between the ages of 9 and 14 should place only brief calls on mobile handsets to limit exposure to radiation, out of concern that young people's brains are still developing."

"The concern among some scientists is that exposure to radio waves that carry calls potentially could cause harm."

The U.S. Food and Drug Administration (FDA) said in a statement that "With regards to the safety and use of cellphones by children, the scientific evidence does not show a danger to users of wireless-communication devices, including children."

The National Institutes of Health takes more or less the same position.

The wireless industry, not surprisingly, says that concerns about a public-health risk remain unfounded.

Stewart's remarks were prompted by the release of a study last week Tuesday by the National Radiological Protection Board.

"That report didn't show any hard information linking cellphones... with effects on health, but discouraged excessive use of mobile phones by children."

A Swedish study released last October found that people who had been using mobile phones for more than 10 years have a four times higher risk of developing acoustic nerve tumors, usually on the side of the head where the phone was used.

However, a similar study in neighboring Denmark showed no such findings.

Many consumer groups in the U.S. point out that much of the research on cellphone safety is sponsored by the wireless industry, which obviously has a huge vested interest in such studies showing no danger.

The FDA's Radiation Biology Laboratory spends about $1 million a year on research in this area, conducted through a joint agreement between industry and the FDA.

Howard Cyr, who heads the lab, says that the industry funds the research but has a "hands-off" approach.

Right - translated, that means that if the results don't come out "right," the hands that give the money will be off.

The problem with trying to show whether or not cellphones are dangerous is that the proof of danger, say a higher incidence of brain tumors in the affected side, occurs so seldom.

Thus, a four-fold increase may mean, in real terms, that 4 people in 100,000 develop an acoustic neuroma as opposed to 1 in 100,000.

You need an enormously large denominator to start seeing differences, and that means it's very difficult to carry out such studies.

That's precisely the reason drugs which seemed safe in clinical trials before their release later turn out to have unanticipated dangers: the denominator gets huge, in the form of millions of people taking the medication, and so side effects like fatal rhabdomyolysis (muscle-wasting), now associated with the statin-class of cholesterol-lowering drugs, only rear their dangerous heads after widespread use.

Also, random statistical variation can play a role in seemingly "positive" results.

Having said that, it's still virtually impossible to prove a negative.

To say that cellphones are unequivocally safe is to go further than the data permit.

If you're concerned, I'd use an earpiece or headset as the FCC suggests.

That keeps the phone well away from your melon.

If you're worried about your kid's cabeza, well, give them an earpiece too.

Though the high geek factor will probably guarantee it'll gather dust at the bottom of a purse or backpack.

It's worth reflecting for a moment about Einstein's insight that mass and energy are variations on a theme of radiation.

Mass explodes: energy results.

Radiation is the currency by which one translates into the other.

So if, in the final shakedown, we're nothing but Joni Mitchell's stardust, then we are not only golden, we're radiation, each of us a walking, talking, dreaming, scheming energy field.

So what's a few more rays?