Several researchers spent almost $30-million over 10 years on the largest-ever study into the possible health effects of cellphones on the human brain.
The conclusion they reached is that cellphones pose a risk to the brain only if you use one to repeatedly bash someone in the head.
OK, that last part was not technically part of the Interphone study, which involved 13,000 test subjects in 13 countries, and was an attempt to once-and-for-all determine if there was a link between brain cancer and cellphones. But the study did scientifically conclude that “overall, no increase in risk of [brain tumours] was observed with use of mobile phones,” in a paper published this week.Well, that’s certainly pleasing news, isn’t it?
Not according to these stories: “Heavy use of cell phones may increase tumour risk: study” (Globe and Mail); “Cellphone brain cancer link still open question (CBC); “Cellphone, cancer link still unclear after largest-ever study” (Toronto Star).
Goodness. Those headlines sound a lot more ominous than the overall conclusion. What gives? The short answer is that the alleged link between cellphones and brain cancer is the story that will not go away, no matter what the studies say, thanks to the handy established narrative that the heartless wireless lobby has bullied/bought governments the world over into silence about the deadly risks of their devices.
So instead of simply reporting the study’s main finding — no link between brain cancer and cellphone use — much of the world’s media instead framed their stories by focusing on the one element of the research that hinted at trouble, even though the scientists themselves said it could not be trusted.
From the study’s conclusion: “There were suggestions of an increased risk of [tumours] at the highest exposure levels, but biases and error prevent a causal interpretation.”
It took, though, until the sixth paragraph of that Globe story before it noted suspicion about the results for heavy cellphone use, and even then only a passing mention that it wasn’t “conclusive.”
I’ll say it wasn’t conclusive. The test subjects who reported the highest amount of cumulative cellphone use, more than 30 minutes a day, often overestimated the time they spent with a phone next to their head. Many reported more than five hours a day in which they were talking on a cellphone and some reported more than 12 hours a day. The paper notes, in a fine bit of understatment, “there is reasonable doubt about the credibility of such reports.” More importantly, because cancer-stricken subjects were told what the study was about, they could have been “more motivated to recall and report a publicized potential risk factor for their disease.”
The biggest knock against the heavy-use findings, though, is that it was the only category that showed any link at all between cellphone use and cancer. For every type of cellphone user other than those who reported more than 30 minutes of calls a day, from occasional to light to moderate use, the study showed a lower risk of brain cancer than for those who never used a cellphone at all.
The study even found that among respondents who did not estimate the cumulative time spent on the phone but instead estimated just the number of calls they made, there was again zero correlation between number of calls made and cancer risk. Even the most frequent callers had a slightly lower risk of brain tumours than did people who never made calls on a mobile device.
As the study says, “the lack of a consistently increasing risk with dose, duration of exposure and time since first exposure weigh against cause and effect.” No cause and effect, you say? Funny, but I didn’t find that line in any of the stories cited earlier.
The researchers acknowledged the positive findings, though you had to read down a way to find them.
“Based on the totality of the scientific evidence, there’s probably not a compelling reason to regulate cellphone use in some way,” one told the Star. He hedged a little with the CBC: “It’s kind of embarrassing as a scientist to say we’ve just spent 12 years and 20-million euros and we think there’s not much of a risk there, but we’re not entirely sure.”
But in a journal article accompanying the study, two scientists wrote “the tired refrain ‘more research is needed’ fully applies in this instance.”
Does it really? It’s not like this study was an outlier. As it says, “Our results are consistent with most of the research published to date.”
So that, then, is why the link between cellphones and brain cancer remains “unclear.” Because there is not one to see.
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