Two government led studies in the U.S. have indicated that there is very little health risk, if at all, from the use of cellphones on humans. One of the studies was done on rats and the other on mice.
Even as cell phones have turned out to be an integral part of the life of most people, there have been intense interest and debate about health safety issues of humans related to the use of the device for years. And millions of people could be harmed even due to a minute risk.
The two studies that were cost $25 million and conducted over a period of 10 years, dealt with the effects of the type of radiation emitted by cellphones. These studies are being touted to be the most extensive one on the issue till date.
High and long-term exposure to the radiation emitted by cell phones caused tumors in the hearts of male rats. But neither were the female rats or mice develop such problems
John Bucher, a senior scientist at the National Toxicology Program, said during a telephone news briefing that the results of the studies were not applicable directly to humans because they were conducted on rodents. But the study exposed the rodents to cell phone radiations for nine hours a day for two years which is much more than an average human would experience from use of cell phones. Therefore, the results were no applicable too.
Bucher has not bene induced to alter his cell phone usage or that of his family members due to the results of the experiments, he said. But the heart tumors in rats — called malignant schwannomas, that developed after exposure to cell phone radiation, are similar to acoustic neuromas in humans which is a form of a benign tumor and is connected to the nerve which joins the ear to the brain. Some earlier studies had concluded that development of such a tumor in people was due to cellphone use.
There have been about 20 animal studies in this aspect where “the vast majority coming up negative with respect to cancer”, Bucher said.
Dr. Bucher added that attempts at similar studies by other agencies is also being conducted where it is being attempted to determine whether cellphone usage is related to incidents of any form of cancer.
The Food and Drug Administration of the U.S. said in a statement that the study by the toxicology program was respected by it and the agency had already gone through multiple other studies related to health risks from cellphone usage and it had “not found sufficient evidence that there are adverse health effects in humans caused by exposures at or under the current radio-frequency exposure limits.”
“Even with frequent daily use by the vast majority of adults, we have not seen an increase in events like brain tumors”, said the statement from Dr. Jeffrey Shuren, director of the F.D.A.’s center for devices and radiological health.
The study noted that radiation emission is increased when people use cellphone in places where the signals are low and cellphones have to function harder in order to connect, Dr. Bucher said.
According to a statement from the toxicology program, part of the National Institute of Environmental Health Sciences, the two studies done with 3,000 animals, are “the most comprehensive assessments of health effects and exposure to radio-frequency radiation in rats and mice to date.”
(Adapted form NYTimes.com)