When you talk on your cellular phone, your voice is transmitted from the antenna as radio frequency (RF) and microwave (MW) radiation between 800 MHz and 2.5GHz. Exposure to this radiation may have serious health consequences. Every cell phone model sold in the United States has a specific measurement of how much microwave energy from the phone can penetrate the brain. Depending on how close the cell phone antenna is to the head and on the age of the user, between 20% and 80% of the radiation emitted from the antenna is deposited in the user's head. This radiation is absorbed by and actually penetrates the area around the head and up to 2 inches into the brain.
Exposure conditions for cellular phones are unique insofar as there is no other radiation emitting device in the world which you would press against the side of your head for long periods of time. Studies have shown that if the cell phone signal is held next to the brain there are changes in the brainwaves in 70% of people. This testing was done at a level of about 2 microwatts per sq. cm., which is only a fraction of the actual exposure experienced from the cell phone.
Studies have shown that people who sleep with a cell phone by the bed have poor REM sleep, leading to impaired learning and memory. This is related to melatonin production.
