Government agencies clash on cellphone cancer risk
WASHINGTON — Two U.S. government agencies are giving conflicting interpretations of a safety study on cellphone radiation: One says it causes cancer in rats. The other says there’s no reason for people to worry.
The U.S. National Toxicology Program dialled up its concerns about a link to heart and brain cancer from a study of male rats that was made public last winter.
The Food and Drug Administration, which oversees cellphone safety, disagreed with the upgraded warning. And “these findings should not be applied to human cellphone usage,” said Dr. Jeffrey Shuren, FDA’s chief of radiological health.
What’s most important is what happens in humans, not rats, said Dr. Otis Brawley, chief medical officer of the American Cancer Society.
“The incidence of brain tumours in human beings has been flat for the last 40 years,” Brawley said. “That is the absolute most important scientific fact.”
In a $30-million US study, scientists put rats and mice into special chambers and bombarded them with radiofrequency waves, similar to those emitted by older 2G and 3G phones, for nine hours a day for up to two years, most of their natural lives.
The levels the rodents experienced were far higher than people are typically exposed to.
Last February, the toxicology pprogram said there was a small increase in an unusual type of heart tumour in male rats, but not in mice or female rats. The agency concluded there was “some evidence” of a link. Also, the February report cited “equivocal evidence” of brain tumours in the male rats.
Thursday, the agency upgraded its description of those findings. The heart-tumour increase marked “clear evidence” of cancer in male rats, it announced. There is “some evidence” of brain cancer.
The change came after the agency asked outside experts to analyze the findings.
“We believe that the link between radiofrequency radiation and tumours in male rats is real, and the external experts agreed,” said John Bucher, the toxicology agency’s senior scientist.
While his agency said the risks to rats don’t directly apply to people, the study raises safety questions.
The FDA immediately disagreed, firing off a statement assuring the public that “decades of research and hundreds of studies” have made the health agency confident that the current safety limits for cellphone radiation protect human health.
Plus, FDA pointed out confusing findings from the rodent study — such as that the radiated rats lived longer than comparison rats that weren’t exposed to the rays. The toxicology agency said it appeared that the radiofrequency energy helped older rats’ kidneys.
There’s a reason two different government agencies are clashing — they’re asking different questions, said George Washington University public health professor George Gray.
A former science chief for the Environmental Protection Agency, Gray said the toxicology program examined how cellphone radiation affected animals. By looking at what it means for humans, the FDA “brings in more sources of information and data than just these recent tests in rats and mice,” he said in an email. So are celllphones safe? If people are concerned, they could use earphones or speakers, the cancer society’s Brawley said. Those who study risk aren’t hanging up. “My family and I won’t change our mobile phone habits based on this news,” said George Washington’s Gray, co-author of the book Risk: A Practical Guide for Deciding What’s Really Safe and What’s Really Dangerous in the World Around You.