Radio waves silently transmit information all over the world. Discovered in the late 1800s and fundamental in many of the most important technological advances of the 20th century, radio waves are the basis for almost all non-written communication and most wireless technologies. They transmit signals that carry pictures, data, music and conversations invisibly over long distances. Without technology based on radio waves, you might find your day-to-day life nearly unrecognizable.
Many household products we consider necessary depend on radio waves. AM and FM radios, wireless networks, cordless and cellular telephones, radio-controlled toys, television programming, garage door openers and GPS receivers -- all of these, along with countless other devices, depend on silent, invisible radio waves to operate.
Despite their importance, many people have become concerned about the possible negative health effects of excessive radio wave exposure. Specifically, the alleged culprits seem to be cell phones, which transmit their voice and data signals over radio waves, and cell phone towers, which route and receive these signals. Do these technologies cause cancer? Do they affect our brain waves?
Experts disagree about the long-term effects of electromagnetic radiation generated communications infrastructure. However, if there is a problem with cellular technology, it is probably not coming directly from the towers. Any potential danger is likely to be more worrisome for those who personally use cell phones, because the phones are directly against their heads. Also, cell towers operate at low power. This is part of what makes the cell phone system work properly. The level of power from a cell tower is similar to that of a citizens' band (CB) radio. According to the American Cancer Society, the types of radio waves generated by cell phones are unlikely to cause cancer, since they are not ionizing radiation, and they have no ability to alter the DNA of human cells so that they produce cancer [source: ACS].
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