How common is brain cancer? Has the incidence of brain cancer changed over time? Why is there concern that cell phones may cause cancer or other health problems? Cell phones emit radiofrequency energy radio wavesa form of non-ionizing radiation, from their antennas.
Tissues nearest to the antenna can absorb this energy. As of Decemberthere were more than This is a nearly threefold increase from the million users in Globally, the number of subscriptions is estimated by the International Telecommunications Union to be 5 billion.
However, improvements in cell phone technology have resulted in devices that have lower power outputs than earlier models. The NCI fact sheet Electromagnetic Fields and Cancer includes information on wireless local area networks commonly known as Wi-Ficell phone base stations, and cordless telephones.
What is radiofrequency energy and how does it affect the body? Radiofrequency energy is a form of electromagnetic radiation. Electromagnetic radiation can be categorized into two types: Electromagnetic radiation is defined according to its wavelength and frequency, which is the number of cycles of a wave that pass a reference point per second.
Electromagnetic frequencies are described in units called hertz Hz. The energy of electromagnetic radiation is determined by its frequency; ionizing radiation is high frequency, and therefore high energy, whereas non-ionizing radiation is low frequency, and therefore low energy.
More information about ionizing radiation can be found on the Radiation page. The frequency of radiofrequency electromagnetic radiation ranges from 30 kilohertz 30 kHz, or 30, Hz to gigahertz GHz, or billion Hz.
The human body absorbs energy from devices that emit radiofrequency electromagnetic radiation. The dose of the absorbed energy is estimated using a measure called the specific absorption rate SARwhich is expressed in watts per kilogram of body weight. Exposure to ionizing radiation, such as from x-rays, is known to increase the risk of cancer.
The only consistently recognized biological effect of radiofrequency energy is heating. The ability of microwave ovens to heat food is one example of this effect of radiofrequency energy.
However, it is not sufficient to measurably increase body temperature, and there are no other clearly established effects on the body from radiofrequency energy. Whereas one study showed increased glucose metabolism in the region of the brain close to the antenna compared with tissues on the opposite side of the brain 2the other study 3 found reduced glucose metabolism on the side of the brain where the phone was used.
The authors of these studies noted that the results are preliminary and that possible health outcomes from changes in glucose metabolism are still unknown. Such inconsistent findings are not uncommon in experimental studies of the biological effects of radiofrequency electromagnetic radiation 5.
Some contributing factors include assumptions used to estimate doses, failure to consider temperature effects, and lack of blinding of investigators to exposure status.
How is radiofrequency energy exposure measured in epidemiologic studies? Direct measurements are not yet possible outside of a laboratory setting.
Estimates take into account the following: Radiofrequency energy, unlike ionizing radiationdoes not cause DNA damage that can lead to cancer. Its only consistently observed biological effect in humans is tissue heating.
In animal studies, it has not been found to cause cancer or to enhance the cancer-causing effects of known chemical carcinogens 6 — 8. This investigation was conducted in highly specialized labs that can specify and control sources of radiation and measure their effects.
In Februarytwo draft technical reports summarizing the findings were made available in advance of the formal peer-review process in March Peer review is a critical component of the scientific process to ensure that research findings are meaningful, accurate, and appropriately interpreted.Radiation therapy treats cancer by using high-energy waves to kill tumor cells.
The goal is to destroy or damage the cancer without hurting too many healthy cells. This treatment can cause side. Scientists may have found the cause of the world’s sudden dwindling population of bees- and cell phones are to blame. Research conducted in Lausanne, Switzerland has shown that the signal from cell.
At home and at work, dozens of wireless networks are streaming invisible radio waves through your space and body. (So are the phones, computers, Bluetooth speakers and other devices that connect. Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body.
These contrast with benign tumors, which do not spread to other parts of the body. Possible signs and symptoms include a lump, abnormal bleeding, prolonged cough, unexplained weight loss and a change in bowel movements. While these symptoms may indicate cancer, they.
For people with PTSD, imagining a threatening scenario might reduce symptoms. It's safe to say no one likes germs, and if you're an outright germophobe, you might want to listen extra closely to this one. Cell phones have about 10 times as many germs as the average toilet seat, and if that doesn't make you cringe, nothing will.