Cell Phones and Brain Cancer : Studies in Perspective

by Food and Drug Administration (FDA)

(Page 2 of 3)

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.

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.

Based on the evidence so far and possible limitations in some studies' research methods, FDA is closely following ongoing research into whether there might be any association between cell phones and cancer, according to the agency's Feigal.

A long-term study 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.

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FDA is A United States government body that oversees medical devices, including contact lenses, intraocular lenses, excimer lasers and eyedrops. In the US, these products must be approved by the FDA before they can be marketed.