A bunch of experts convened by the World Health Organization have decided that cellphones might pose a risk of brain cancer in humans.
The finding that cellphones are a possible carcinogen is a bit of surprise. Only last year, a WHO-organized study of cellphone risks that was the largest conducted to date found scant evidence to support a link between cellphones and brain cancers.
But a group of 31 experts from 14 countries conducted a review of the scientific literature and determined that the evidence, though limited, could support a connection between cellphone use and brain tumors — cancerous gliomas and acoustic neuromas, which are noncancerous. (A summary of the findings is described in this press release.)
The evidence didn't support a link between the electromagnetic radiation emitted by cellphones with other cancers.
And, it should be pointed out that the group, working under the auspices of the International Agency for Research on Cancer, didn't put a number on the increased risk. "The evidence, while still accumulating, is strong enough to support a conclusion," said a statement by Dr. Jonathan Samet, a University of Southern California epidemiologist who chaired the panel of experts. "There could be some risk, and therefore we need to keep a close watch for a link between cell phones and cancer risk."
Cellphones got labeled as risk level "2B" in the IARC system, a designation that covers a long list of chemicals, including gasoline and lead, as well as the occupational hazard that comes with being a firefighter.
The findings by the cancer experts will be evaluated by WHO and health agencies in individual countries.
The full review will be published in the July 1 issue of the medical journal The Lancet Oncology and will be available online in a few days, the WHO's IARC said.
Data Dump: For a round up of relevant research on cellphones and health risks, check out this post by Eliza Barclay.
ROBERT SIEGEL, Host:
NPR's Richard Harris joins us now to talk about this development. Hi, Richard.
RICHARD HARRIS: Hi, Robert.
SIEGEL: And first of all, what does it mean when the World Health Organization says that something possibly causes cancer?
HARRIS: So those that fall into the possible category, which we're talking about here, have raised suspicions either in animal studies or in population studies. That would include, of course, many chemicals but also things like pickled vegetables, coffee, doing work as a carpenter. And now, the electromagnetic fields from cell phones.
SIEGEL: We'll skip carpentry and coffee. What's the evidence that the cell phone use might cause cancer?
HARRIS: Now, this is not definitive, but Dr. Jonathan Samet from the University of Southern California, who chaired the panel, said in a statement that, quote, there could be some risk and therefore, we need to keep a close watch for a link between cell phones and cancer risk.
SIEGEL: So if there is actually a link, how in theory might cell phones cause cancer, if they do?
HARRIS: And unfortunately, animal studies on this don't really help clarify the picture.
SIEGEL: So it's a pretty confused picture. I mean, how would scientists go about sorting this out?
HARRIS: The WHO finding also could encourage more animal studies and also, they're hoping, more careful cancer monitoring. For example, the WHO points out that there are no studies in children as yet.
SIEGEL: Well, since the WHO has said that it is possible that there might be some link between cell phone use and cancer, what - do they recommend that people do anything, or is this not even worth basing a recommendation on?
HARRIS: The other thing is that if there is a risk, I think it's fair to say it would be quite small because by now there's something like five billion people around the world who use cell phones...
SIEGEL: Use cell phones, yes.
HARRIS: However, I should say that it is clear that cell phones are a true public health in one sense, and that is the government says that more than 5,000 people are killed every year by distracted drivers in the U.S. alone. And, of course, cell phone use is one of the most common distractions.
SIEGEL: So our many listeners who are driving home right now might take that information onboard once again. Thank you, Richard.
HARRIS: My pleasure.
SIEGEL: NPR's Richard Harris, talking with us about the World Health Organization's finding that cell phones could possibly cause cancer. Transcript provided by NPR, Copyright NPR.