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.
Cellular Phones Cellular cell phones first became widely available in the United States in the s, but their use has increased dramatically since then.
Along with the large and still growing number of cell phone users both adults and childrenthe amount of time people spend on their phones has also risen sharply in recent decades.
Cell phones including smartphones give off a form of energy known as radiofrequency RF wavesso some concerns have been raised about the safety of cell phone use. With respect to cancer, concern focuses on whether cell phones might increase the risk of brain tumors or other tumors in the head and neck area.
How do cell phones work? Cell phones work by sending signals to and receiving them from nearby cell towers base stations using RF waves. This is a form of electromagnetic energy that falls between FM radio waves and microwaves.
Like FM radio waves, microwaves, visible light, and heat, RF waves are a form of non-ionizing radiation. RF waves are different from stronger ionizing types of radiation such as x-rays, gamma rays, and ultraviolet UV light, which can break the chemical bonds in DNA. At very high levels, RF waves can heat up body tissues.
This is the basis for how microwave ovens work.
But the levels of energy given off by cell phones are much lower, and are not enough to raise temperatures in the body. How are people exposed? The RF waves from cell phones come from the antenna, which is part of the body of a hand-held phone.
The waves are strongest at the antenna and lose energy quickly as they travel away from the phone.
The phone is typically held against the side of the head when in use. The body tissues closest to the phone absorb more energy than tissues farther away. Many factors can affect the amount of RF energy to which a person is exposed, including: The amount of time the person is on the phone.
Whether or not the person is using the speaker mode on the phone or a hands-free device. Using one of these allows the phone to be held away from the head. The distance and path to the nearest cell phone tower. Cell phones adjust their power to use the minimum amount for a good signal.
Being farther away from the tower requires more energy to get a good signal, as does being inside a building. The amount of cell phone traffic in the area at the time. Higher traffic may require more energy to get a good signal.
The model of phone being used. Different phones give off different amounts of energy. What is the specific absorption rate SAR of a cell phone? Different cell phones have different SAR levels. The listed SAR value is based only on the phone operating at its highest power, not on what users would typically be exposed to with normal phone use.
Do cell phones cause tumors? Because cell phones usually are held near the head when being used, the main concern has been whether they might cause or contribute to tumors in this area, including: Malignant cancerous brain tumors such as gliomas Non-cancerous tumors of the brain such as meningiomas Non-cancerous tumors of the nerve connecting the brain to the ear vestibular schwannomas, also known as acoustic neuromas Non-cancerous tumors of the salivary glands A few studies have also looked at possible links to other types of cancer, such as skin cancer and testicular cancer.
Researchers use 2 main types of studies to try to determine if something might cause cancer. Lab studies usually expose animals to something like RF energy to see if it causes tumors or other health problems. Researchers might also expose normal cells in a lab dish to RF energy to see if it causes the types of changes that are seen in cancer cells.
Another type of study looks at cancer rates in different groups of people.
Such a study might compare the cancer rate in a group exposed to something like cell phone use to the rate in a group not exposed to it, or compare it to what the expected cancer rate would be in the general population.PITTSBURGH (KDKA) – Can cellphones really cause cancer?
It’s been a question that’s dogged researchers for years. However, a group . The “do cell phones cause cancer” debate is still not settled and will likely take years to play out. Here’s what we do know, though: Cell phone radiation is radiofrequency energy and a type of electromagnetic radiation classified as non-ionizing radiation, similar to harmful microwaves and radar.
May 31, · (CNN)-- Radiation from cell phones can possibly cause cancer, according to the World Health pfmlures.com agency now lists mobile phone use in the same "carcinogenic hazard" category as lead.
Jun 06, · Phones Leer en español Cellphones and cancer: 9 things you should know right now.
The debate over whether cellphone use is hazardous to your health isn't over, and it may never be. There are three main reasons why people are concerned that cell phones (also known as “mobile” or “wireless” telephones) might have the potential to cause certain types of cancer or other health problems.
With the positive case-control studies seen in humans and a similar positive finding in a well-conducted laboratory study in rats, the evidence that call phones can cause cancer has strengthened.