Ionizing radiation carries enough energy to break chemical bonds, knock electrons out of atoms, and cause direct damage to cells in organic matter. In fact, ionizing radiation carries more than a billion times more energy than does non-ionizing radiation. A little ionizing radiation can be used to produce x-ray images for diagnosis.
A lot of ionizing radiation is needed to kill cancer cells in radiation therapy. By contrast, non-ionizing radiation does not have enough energy to break chemical bonds or strip electrons from atoms. In these types of studies, it can be hard to interpret any possible link between cancer and an exposure.
People with cancer are often thinking about possible reasons for it, so they may sometimes recall their phone usage differently from people without cancer. With these limitations in mind, it is important to continue to study the possible risk of cell phone exposure, especially with regard to use by children and longer-term use.
The American Cancer Society ACS does not have any official position or statement on whether or not radiofrequency RF radiation from cell phones, cell phone towers, or other sources is a cause of cancer. ACS generally looks to other expert organizations to determine if something causes cancer that is, if it is a carcinogen , including:. Other major organizations also sometimes comment on the ability of certain exposures such as cell phone use to cause cancer.
More recently, the US Food and Drug Administration FDA issued a technical report based on studies published between and , as well as national trends in cancer rates. So far, the National Toxicology Program NTP has not included RF radiation in its Report on Carcinogens , which lists exposures that are known to be or reasonably anticipated to be human carcinogens.
For more on this report, see Known and Probable Human Carcinogens. Those evaluating the potential risks of using wireless devices agree that more and longer-term studies should explore whether there is a better basis for RF safety standards than is currently used. Scientific studies are underway to determine whether cell phone use may cause health effects. It is not clear at this time that RF waves from cell phones cause harmful health effects in people, but studies now being done should give a clearer picture of the possible health effects in the future.
Until more is known, there are several things that people who are concerned about RF waves can do to limit their exposure. Use the speaker mode or video chat feature on the phone, or a hands-free device such as a corded or cordless earpiece.
This moves the antenna away from your head, which decreases the amount of RF waves that reach the head. Corded earpieces emit virtually no RF waves although the phone itself still emits small amounts of RF waves that can reach parts of the body if close enough, such as on the waist or in a pocket.
Texting instead of talking on the phone may be another way to reduce your exposure. But it may not be a good option in some situations, especially if you are driving. For safety reasons, it is especially important to limit or avoid the use of cell phones especially texting while driving. This is one of the most obvious ways to limit your exposure to RF waves from cell phones. For example, you may want to limit the amount of time you spend talking on the phone at least with your phone up to your ear.
Consider choosing a phone with a low SAR value. Different models of phones can give off different levels of RF waves. The FCC has links to some of these sites. If you know the FCC identification ID number for your phone model which can often be found somewhere on the phone or in the user manual , you can also go to the following web address: www. Fifth generation 5G cellular networks are now being rolled out in many parts of the United States and in other countries. But the newer 5G signals still use RF waves, so they are still forms of non-ionizing radiation, which is not thought to have the ability to directly damage DNA.
The studies that have been done so far to look at possible links between cell phone use and cancer have focused on older generation mainly 2G and 3G signals. At this time, there has been very little research showing that the RF waves used in 5G networks are any more or less of a concern than the other RF wavelengths used in cellular communication.
For more on 5G networks, see Cell Phone Towers. Transportable phones are also known as "bag phones. Because they are most commonly stored inside the car with the phone user, or carried by the phone user, bag phones can be a greater source of RF exposure than mobile phones. Transportable telephone use is declining as portable phones become more popular. Mobile phones , also called "car phones," usually have an antenna mounted on the outside of a car-on the window, fender, roof, or trunk.
The antenna of a cellular phone is the phone's primary source of radio frequency. The metal surface of a car provides a shield between the mobile phone user and the energy associated with the antenna. The physical distance between the mobile phone user and the antenna also serves as protection against RF energy.
Because of these two obstacles-the metal car surface and the physical separation-users of mobile phones are thought to have little exposure to RF energy.
The antenna of a portable phone is integrated into the body of the phone. Because the antenna of a portable phone is close to the phone user's head, portable phones pose greater RF exposure than the other types of cordless phones.
Cellular phones are an important source of RF exposure for those who use them.
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