June 8th, 2012
03:26 PM ET
Editor's note: Last summer, this article was one of the most popular on the Chart. We're republishing to share these important tips again with you.
Scientists at the World Health Organization list mobile phone use in the same "carcinogenic hazard" category as lead, engine exhaust and chloroform.
There haven't been enough long-term studies to make a clear conclusion if radiation from cell phones is safe, but there was enough data to persuade the WHO of a possible connection to make them upgrade the category in May 2011.
Cell phones use non-ionizing radiation, which doesn’t damage DNA the way ionizing radiation does. The cell phone radiation operates more like very low power microwaves, but nobody really likes to think of leaning their face on a low-powered microwave.
If the WHO’s labeling of cell phone use as "possibly carcinogenic to humans" has you alarmed, here are some quick basic tips to limit your exposure.
It’s no coincidence that most cell phones come with a wired ear piece.
A wired headset will automatically decrease your radiation exposure because the phone is away from the body. Every inch you can get away from the body reduces the amount of radiation you are absorbing.
A wired headset may still transmit radiation through the wire – but it is a very low level. If that is a concern, you can buy a ferrite bead for just a few bucks at most electronic stores. It attaches to the wire and it absorbs any radiation traveling through the wire, reducing how much enters your body.
And it’s not too inconvenient. CNN’s chief medical correspondent Dr. Sanjay Gupta said he uses an earpiece because his neck doesn’t hurt as much after being on a long phone call. Gupta: Cell phones, brain tumors and a wired earpiece
Use the speakerphone
This could get quite annoying, if you’re in a public place. But experts say that using the speakerphone function is helpful because you’re keeping the phone away from your brain. Every inch you can get the phone away from your body reduces the radiation. For example, holding out the cell phone by two inches drops the radiation by a factor of four, Magda Havas, an associate professor with the Institute for Health Studies at Trent University in Ontario, Canada, had told CNN.
But try not to share your conversation with the whole world. Thanks.
Don’t wear Bluetooth all the time
Bluetooth wireless earpieces will expose you to some radiation. However, it would be much less radiation than a cell phone.
The problem is that most people wear their Bluetooth all the time. And this isn’t a good look on anyone.
If you use a Bluetooth device, switch it from ear to ear so you don't have too much exposure on one side. Just take it out of your ear when you aren't on the phone.
Avoid radiation hot spots
Cell phones don’t always emit the same level of radiation. For example, your phone will emit the most radiation when connecting to cellular towers.
But a moving phone (like if you are talking while driving) will continually connect to towers that come in and out of range - and this automatically increases power to a maximum as the phone repeatedly attempts to connect to a new antenna. A weak signal will also cause your phone to work harder, giving off more radiation. So avoid using your phone in elevators, buildings and rural areas. Research shows your device emits more radiation when transmitting than when receiving.
Read the fine print
Most of us ignore those manuals that come with our gadgetry. But most cell phone safety manuals tell consumers to not keep the phone next to their head, or even in your pocket. Apple iPhone 4 says 5/8 inch away from the body when transmitting. And the BlackBerry Bold says to keep it least 0.98 inch from your body when the BlackBerry device is in use.
If you keep it next to your body, the manufacturers can't guarantee that the amount of radiation you're absorbing will be a safe level.
Don’t talk, text
If you don’t want to hold the phone next to your face all the time, send text messages or use your email or messaging services if you have a smartphone. This way you avoid putting the phone to your head altogether.
And our friends at CNN Tech say the general rule of thumb is that the smarter the phone, the more radiation.
CNN's John Sutter contributed to this blog.
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