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Q & A: Electromagnetic energy and cell phones

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Most recent answer: 08/20/2008
Q:
Is there anyway a diode attached to a cell phone could protect the user from harmful electromagnetic engery?.
- Pamela Ford (age 57)
central point, oregon
A:
I am suspicious about claims that cell phones' electromagnetic emissions are harmful (just as it has been shown repeatedly that the low-frequency fields around power lines do not cause measurable harm). But I could be wrong on that.

Cell phones work by emitting radio-frequency electromagnetic waves; stopping this emission means they won't work. You can reduce the electromagnetic wave strength around your body by shielding your body with a conductive sheet -- metal foil, a metal helmet, or a metallic mesh that has holes that are smaller than the wavelength of the cell phone's waves. All of these are ungainly, ugly, or impractical.

Cell phones cause more harm by distracting people while they are driving cars or doing other attention-intensive activities. I have even heard of batteries exploding in rare instances.

Tom

(published on 10/22/2007)

Follow-Up #1: elctromagnetic popcorn

Q:
Can electromagnetic energy pop pop corn? I saw a video where four cell phones where laid on a table top with their tops facing each other. Kernels of pop corn were placed in the center. Once the phones started ringing, the pop corn started to pop. If it can pop popcorn, couldn't it be scrambling our brain cells too?
- Lori (age 46)
Wailuku, HI
A:
You can certainly pop corn with EM radiation. That's how microwave popcorn works. I'm a little surprised that phone radiation would be strong enough to do it. Cell phones do emit more radiation when they're just starting to make contact with the cell towers than after they settle down.
There have been several attempts to study the medical effects of cell phones on their users. Most find no effects. That doesn't mean the effects are necessarily zero, but it does mean they can't be very large. i guess that in practice having only one phone dumping energy into a brain, which is cooled by steady blood flow, just doesn't heat it up much.

Mike W.

This is most certainly a scam.  Try Googling "popcorn scam" and read about all kinds of variations on this.

LeeH

(published on 08/20/2008)

Follow-up on this answer.