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Cell Phones, Cancers and Brain Tumors. Do cell phones cause Cancer?What is the REAL story?
Introduction
Cell phones and cancer are in the news all the time now it seems. But almost everyone uses cell phones. All over the world, tens of millions of people are pressing them against their heads for hours every day. Worldwide, the number of cell phone users is estimated to be approximately 5 billion in 2011 and that number has continued to climb.
So what's the fuss? Is cancer caused by cell phones a serious concern, or the media's panic-du-jour?
A cell phone, and a household cordless phone, use a low level form of microwave radiation to send and receive their signals. (see "How do cell phones work" here.) Microwaves, as you know, are used to cook food. As the radiation penetrates tissue it causes it to heat.
Is this a problem for us with cell phones? That is the current debate. Let's examine the positions and the known evidence, without hype or prejudice. As always, EHSO will provide citations and links to the sources of any evidence provided, so you can verify it for yourself.
Positions, pro and con:
Cell phones are dangerous:
They emit microwaves.
They produce heat.
You hold the source of the emission close to your brain.
There are claims that people have had brain tumors in the exact size, shape and position as the antenna on their cell phone.
Cell phones are safe:
Cell phones use a very, very low level of radio frequency (rf) energy - too low to cause damage.
The type of energy emitted is non-ionizing - meaning it doesn't cause damage to chemical bonds or dna.
Hundreds of millions of people have been using cell phones and cordless phones for years. If there were a problem, we would have seen it by now.
Latest News:
October 21, 2011 - Largest Study Ever on Cell Phones and Cancer Finds No Link - The biggest study to look for any connection has found no link between cell phones and cancer. It followed more than 358,000 people for 13 years and concluded heavy cell phone users have the same cancer rates as people who don't use cell phones. The study, out of Denmark, confirms a smaller one reported on last year. It also contradicts the WHO-IARC study and confirms the assessments of the Food and Drug Administration and the Federal Communications Commission.
May 31, 2011 - WHO (World Health Organization) IARC just announced that radiation from cell phones can possibly cause cancer, as reported by CNN. The agency now lists mobile phone use in the same "carcinogenic hazard" category as lead, engine exhaust and chloroform. Note that this is a reversal of WHO's previous position. According to CNN, the Apple iPhone 4 safety manual warns users, "When using iPhone near your body for voice calls or for wireless data transmission over a cellular network, keep iPhone at least 15 mm (5/8 inch) away from the body." and Blackberry Bold advises users to, "keep the BlackBerry device at least 0.98 in. (25 mm) from your body when the BlackBerry device is transmitting." See this page for the IARC's page on the subject.
February 22, 2011 - Cell Phone Calls Alter Brain Activity, Scientists Say; Fox News, Reuters. Spending 50 minutes with a cellphone plastered to your ear is enough to change brain cell activity in the part of the brain closest to the antenna. But whether that causes any harm is not clear, scientists at the National Institutes of Health said on Tuesday, adding that the study will likely not settle recurring concerns of a link between cellphones and brain cancer.
May 17, 2010 - According to the International Agency for Research on Cancer (funded in part by WHO, the World Health Organization) using a cell phone for as little as 30 minutes may increase your risk of getting a brain tumor (glioma). The study is reported to have included 13,000 participants over 10 years. But we have not seen the details of this study. As soon as we find a source, we'll publish a link to it.
March 03, 2010 - Yahoo News and CNN reports that Maine may require a warning about cell phones being a possible cause of brain cancer. Dr. Derva Davis Mt Sinai Medical center, and Dr. David Carpenter Albany University spoke in favor of the proposed bill.
January 2010: Cell Phones may protect against Alzheimer's. Study by Dr. Gary Arendash at the Florida Alzheimer's Disease Research Center. For the complete story, see Business Week's report or Fox News report.
Studies, Facts and Evidence
What is the radiation produced by a cell phone?
Like televisions, alarm systems, computers, and all other electrical devices, Cell phones (also called mobile phones) are radio devices that use Radiofrequency (Rf) energy emit electromagnetic radiation. They operate at low power (less than 1 watt) by transmitting and receiving electromagnetic radiation in the radiofrequency (RF) end of the spectrum. Radiation which is called "ionizing" can be absorbed by tissue and break molecules apart, such as gamma rays and x-rays, are known to cause cancer. The concern is that the cell phone and it's antenna (the source of the radiation) are held close against the head)
The damage to the dna molecules is thought to be the cause. The radiation that a cell phone uses is also part of the same electromagnetic spectrum, but is not ionizing. For this reason, the US FDA can regulate these devices to ensure that the radiation doesn't pose a health hazard to users, but only once the existence of a public health hazard has been established. (See "It's Not a Food or Medical Product, So Why FDA?") , RF energy was mistakenly thought to similarly cause cancer.
Power
Newer phones are digital. The older analog phones are expected to be phased out by 2006. The major difference is that analog phones use much more power than digital. Analog use about 1.3 Watts, while a digital mobile phone is designed to operate at a maximum power level of 0.6 watts (see http://www.telecom.globalsources.com/MAGAZINE/TS/0209/PANALOG.HTM By comparison, a household microwave oven uses between 600 and 1,100 watts.
Frequency
In the United States, mobile phones operate in a frequency ranging from about 850 to 1900 megahertz (MHz). In that range, the radiation produced is in the form of non-ionizing radiofrequency (RF) energy. This RF energy is different than the ionizing radiation like that from a medical x-ray, which can present a health risk at certain doses.
Ionizing gamma rays and x-rays can cause cancer when their energy is absorbed by the tissue and chemical bonds are broken, damaging DNA. RF energy, on the other hand, produces heating of tissue. Although there is a small amount of experimental evidence that suggests RF energy can impact DNA in rats, this data has been contradicted by several other animal studies and is not well substantiated. Even if true, the doses administered in these animal studies were much larger than the exposure in humans and may have no relevance to cell phone use at all. So although the RF energy emitted by cell phones is in the electromagnetic spectrum, and other forms of electromagnetic radiation can cause cancer, RF energy is very different and has not been shown to cause cancer.
At high enough levels, RF energy, too, can be harmful, because of its ability to heat living tissue to the point of causing biological damage. In a microwave oven, it's RF energy that cooks the food, but the heat generated by cell phones is small in comparison.
A mobile phone's main source of RF energy is its antenna, so the closer the antenna is to a phone user's head, the greater the person's expected exposure to RF energy.
Because RF energy from a cell phone falls off quickly as distance increases between a person and the radiation source (actually, by the distance squared), the safety of mobile phones with an antenna mounted away from the user, like on the outside of a car, has been presumed to be safe. The distance and the effect of the car acting as a Gaussian cage would virtually eliminate the radiation inside the car. Also not presently in doubt is the safety of those so-called cordless phones that have a base unit attached to a home's telephone wiring and operate at much lower power levels than cell phones.
Many experts say that no matter how near the cell phone's antenna--even if it's right up against the skull--the six-tenths of a watt (typically) of power emitted couldn't possibly affect human health.
Scientific Studies to Date
Some mobile phone users have been diagnosed with brain cancer, and many others who have not used mobile phones have gotten the disease, too. Each year in the United States, brain cancer occurs at a rate of about six new cases per 100,000 people. Among the 100 million Americans who own mobile phones, then, about 6,000 cases of brain cancer would be expected among them in a year, even if they had not used mobile phones.
Scientific studies have focused on the question of whether the statistical risk of getting brain cancer is increased in those who use mobile phones compared to non-users, leaving to the courts the judgment of whether Chris Newman or other individuals would have gotten the disease had they not used a cell phone.
Two types of studies are generally used to investigate suspected cancer causes: epidemiological studies, which look at the incidence of a disease in certain groups of people, and animal studies. This fact sheet from the National Institute of Cancer provides references to more studies.
Epidemiological studies are sometimes difficult to carry out in a way that can determine whether a cause-and-effect relationship exists between a single variable in a person's life (in this case, cell phone use) and the person's disease (brain cancer). Some factors that complicate research into the asserted link between cell phones and brain cancer: Brain cancer can take years or even decades to develop, making possible long-term effects of mobile phone use difficult to study; mobile phone technology is ever-evolving; and so many lifestyle factors--even down to the precise position in which a person holds the phone, as well as his or her own anatomy--can affect the extent of radiation exposure.
Studies in animals are easier to control, but entail complications of their own. For example, how should results obtained in rats and mice be interpreted in terms of human health risks? And how can scientists account for the fact that these studies sometimes expose animals to RF almost continuously--up to 22 hours a day--and to whole-body radiation, unlike people's head-only exposure?
While studies generally have shown no link between cell phones and brain cancer, there is some conflicting scientific evidence that may be worth additional study, according to FDA. (See "Studies"). The FDA says on their website that they are closely following ongoing research into whether there might be any association between cell phones and cancer.
A long-term study begun in 1994 by the government's National Cancer Institute is already under way to examine possible risk factors for brain cancer. It compares past usage of mobile phones (as well as other environmental, lifestyle, and genetic factors) by 800 people with brain tumors compared with 800 others who don't have tumors.
The study, the first part of which is expected to be published early next year, will provide a "snapshot" of what the risks from cell phones could be, says Peter Inskip, Sc.D., one of the study's principal investigators. But this research, he cautions, has its own limitations. For one thing, the study was started in 1994 and it considers radiation exposures from cell phones that occurred between the mid-1980s and 1998. That time frame in large part predates the explosion in the popularity of cell phones, as well as the introduction of digital phones that work on a fraction of the energy compared with older analog varieties.
Recently, FDA announced that it will collaborate with the Cellular Telecommunications Industry Association (CTIA) on additional laboratory and human studies of mobile phone safety. A "Cooperative Research and Development Agreement" signed in June provides for research to be conducted by third parties, with industry funding and FDA oversight to help ensure the studies' quality.
Specifically, FDA will identify the scientific questions that merit attention, propose research to address those questions, review study proposals from those interested in doing the research, make recommendations on the selection of researchers, and oversee the development of study design. Once research is begun, FDA will review the progress of ongoing studies, review the results of completed studies, and issue a report to the CTIA.
Beyond this planned research, according to the industry association, there are hundreds of scientific studies completed or in progress around the world to investigate RF's possible health effects, with half of them specifically addressing the frequencies used by wireless phones. FDA is a leading participant in the World Health Organization's International EMF (electric and magnetic fields) project to coordinate research and the harmonization of international radiation standards.Ziff-Davis reports that researchers in Australia have reported their hypothesis that normal mobile phone use can lead to cancer. The research group, lead by radiation expert Dr Peter French, principal scientific officer at the Centre for Immunology Research at St Vincent's Hospital in Sydney, said that mobile phone frequencies well below current safety levels could stress cells in a way that has been shown to increased susceptibility to cancer.
The paper, published in the June 2001 issue of the science journal, "Differentiation", says that repeated exposure to mobile phone radiation acts as a repetitive stress, leading to continuous manufacture of heat shock proteins within cells.
Their theory is that these proteins, which are sensitive to heat, are always present in cells at a low level, but are manufactured in larger amounts when the cell is stressed by heat or other environmental factors. These proteins repair other proteins that are adversely affected by the conditions, and are part of the cell's normal reaction to stress. However, if they are produced too often or for too long, they are known to initiate cancer and increase resistance to anti-cancer drugs.
However, this group has reported absolutely evidence nor studies to substantiate this - it is only a theory.
More recently, a Finnish survey of some of the world's most popular mobile phones found the amount of radiation they emit is well below agreed limits and largely in line with data published by manufacturers. The survey conducted by Finland's Radiation and Nuclear Safety Authority (STUK) covered 16 new models made by top handset makers including Finland's own Nokia, Motorola of the United States and South Korea's Samsung Electronics. At this level, the study found that head tissue does not warm significantly and no other harmful effects have been proved scientifically. STUK said the SAR levels in all the 28 models tested so far ranged from 0.45 to 1.12 watts per kilogram. "It is important that also in the future the limits set for radiation from mobile phones and base stations are based on current and confirmed scientific proof of the effects of radiation on health," Kari Jokela, a researcher at STUK, said in a statement. STUK also said that some of its studies have indicated that microwave radiation from mobile phones may cause small changes in how cells operate, but the findings were insufficient for concluding what effects of this radiation had on health. STUK will start testing third-generation UMTS-standard mobile phones during 2005, focusing on the most popular models. Other phones in the current study were made by Sony Ericsson and Siemens.
Finally, as the non-ionizing radiation does have a small heating effect, it is postulated that the effect would be greatest on the eyes and testes, due to the lower amount of blood vessels to help cool these areas.
Perceptions and Concerns
The latest studies may support the generally held position that cell phone radiation is not a substantial hazard, but they will never be able to prove cell phones to be absolutely safe. It is logically impossible to prove a negative, that cell phones can not cause cancer.
Conclusions
EHSO has seen no credible evidence to date that cell phones cause cancer or brain tumors. It is illogical to believe that evidence of unusual brain tumors is covered up when there are hundred's of millions of people using cell phones worldwide. There is a TREMENDOUS amount of junk science and thoroughly ignorant (as in untrained, uneducated) people running around naming themselves as experts and publishing their opinions on the internet. This hype and fear-mongering has only one goal: to puff up the egos and wallets of those propagating nonsense.And the supposed link between mobile-phone use and cancer is even listed among the American Cancer Society's "Top 10 Cancer Myths,"
However, cell phones are still relatively new, and while science does not support that the radiation may not be likely to cause cancer, time may prove differently! And in any case, it may cause some other type of damage (certainly accidents in cars from being distracted while fumbling with the phone!)
So common sense suggests that we each take some prudent precautions; see below.
Precautionary Steps To Take
There are some simple steps that cell phone users can take to reduce any remaining risk:
First, use a headset or speakerphone mode. That moves the phone (and it's antenna) away from your head.
Second, consider reserving the use of mobile phones for shorter conversations or when a conventional phone is not available.
Third, the effects of cellular damage are greatest on growing, developing organisms (i.e., the young), so limit children's use of cell phones!
Finally, in a car, use an external antenna mounted outside the vehicle to move the source of the radiation farther from you!
And don't believe the claims of conmen preying on people's fear of radiation, selling fraudulent devices that they say protect against radiation. These useless items are mostly sold as "shields" on the Internet. Experts says none of these devices work.
To reduce the risk of an accident while driving, here's a simple tip: enter the several numbers you call the most often in a way that brings them to the top of the list, so you can use fewer keystrokes to dial them. For example, the Motorola V60 starts with an alphabetized list when you press the multi-function button; so start your most commonly called number with "AAA", Like "aaaParents" and the next number with "AAB", like "aabHusband", then they will always appear at the top of the list, which should take fewer keystrokes and less time to dial!
Below are a variety of headsets that will allow you to use your cellphone without the potential risks of having the transmitter close to your ear. The blooth versions work with any mobile phone that is bluetooth enabled, which includes Apple iPhones and most Android and smartphones. If your phone does not have blooth, one of the wrired versions will work justthe same. If you play music from your phone, there are steroe headset versions that work both as a headset for talking on the phone and for playing music. These below have the highest customer satistfaction for both safety, reliability and voice / sound quality: