In a study that may shed some light on whether cell-phone use is harmful to callers, Swedish scientists found that radiation emitted by the world's most common mobile phones burns holes in the brains of rats.
Swedish neurosurgeon Leif Salford and his team tested the radiation emitted from Global System for Mobile communications phones on 12- to 26-week-old rats. The age group of the animals tested, researchers say, is equivalent to that of human teenagers – who tend to lead the pack in cell-phone use worldwide. GSM phones are the most commonly used around the globe, particularly in Europe, Asia and the Middle East.
"The situation of the growing brain might deserve special concern, since biological and maturational processes are particularly vulnerable," wrote the study's authors. "We cannot exclude that after some decades of often daily use, a whole generation of users may suffer negative effects as early as middle age."
The cell-phone industry has long disputed the results of studies like Salford's because such effects have not been documented in humans. Both the World Health Organization and U.S. Food and Drug Administration have said there is no evidence that cell-phone radiation is harmful to users, but that there is also no absolute evidence to the contrary either. The New England Journal of Medicine and Journal of the American Medical Association both ruled out that infrequent and short-term cell-phone use – up to five years – causes brain cancer.
Most recently, a federal judge threw out a case brought by a Maryland neurologist who claimed his brain tumor was caused by frequent cell-phone use. Federal Judge Catherine Blake ruled that none of the evidence submitted by Dr. Christopher Newman was substantial enough to warrant a trial.
"We found that the preponderance of scientific evidence continues to show that there is no adverse health effects in using wireless phones," said Jo-Anne Basile, vice president of external relations for the Cellular Telecommunications & Internet Association. "As you know, wireless phones are regulated by strict government standards, and those standards are constantly being reviewed by the federal agencies responsible for the public's health. Part of what they do is that they are always looking at new research to make sure that these rules continue to protect the public's health. This study will be reviewed along with others."
Still, Salford's findings have raised eyebrows in the scientific community and cell-phone industry, and among the public.
The study was published in the peer-reviewed journal Environmental Health Perspectives, a publication of the National Institute of Environmental Health Sciences, which is part of the Department of Health and Human Services. Salford's study is also one of the first to suggest that cell-phone use causes a malady other than brain cancer.
"This is a big story," said Louis Slesin, editor of Microwave News. "I don't think it's good to peg this story as if we are all going to get brain damage. But you can't ignore it."
The Swedish study included three groups of rats that were exposed for two hours to various GSM phones at different levels of radiation. The study found a link between electromagnetic frequency exposure and a leakage in albumin – a protein in human tissue – through the blood-brain barrier. The researchers also noticed that the neuron damage the rats suffered increased in response to the amount of EMF exposure.
The authors of the study acknowledged that their test sample was small, but that "the combined results are highly significant and exhibit a clear dose-response relation."
Such a hole in the brain could prove life-threatening because it would mean that almost anything circulating in the blood – including toxic pollutants – could enter the brain, said Dr. Tom Goehl, editor-in-chief of Environmental Health Perspectives.
"Again this is in adolescent rodents," Goehl said. "It's pretty much hard to jump to humans. But it may be a warning signal that this is something to look at."
Goehl said that, on average, his publication accepts only 20 to 25 percent of 800 studies reviewed each year.
His publication snapped up this study because, unlike most other research of its kind, it didn't focus on whether the devices would cause cancer.
"Now we have another way to look at (this issue)," he said. "Maybe this has a far-reaching effect and ... this is just a warning sign that we need to take a closer look at (this issue)."