May 31, 2011, was a bad day for a society already wary of all sorts of risks from modern technology, a day of celebration for those who champion more concern about those risks, and a day that teaches important lessons about the messy subjective guesswork that goes into trying to make intelligent choices about risk in the first place, for policy makers or for you and me. The International Agency for Research on Cancer (IARC) says radiation from cell phones might cause cancer. OMG!!! Your phone is ringing! Now what?


Do you try to get more information about what the experts say? That won’t help, because they’re pretty unsure themselves. IARC said "…the evidence was… limited among users of wireless telephones for glioma and acoustic neuroma, (two types of brain cancer) and inadequate to draw conclusions for other types of cancers." And here’s what limited means to IARC; "A positive association has been observed between exposure to the agent and cancer for which a causal interpretation is considered…to be credible, but chance, bias or confounding could not be ruled out with reasonable confidence." Dr. Jonathan Samet, head of the IARC group that looked into the issue, said "…there could be some risk, and therefore we need to keep a close watch for a link between cell phones and cancer risk." Keep a close watch?! Thanks a lot! Your phone is ringing!


Do you just figure things are safe until we know more? That’s not much of a strategy either since it will be years before we know about this particular risk for sure. Brain cancer takes a long time to develop, and we are exposed to hundreds of potentially carcinogenic substances, in varying combinations, all the time, so it’s hard to rule out other possible causes. And most cancers aren’t environmental in the first place. Meanwhile, your phone is ringing, right now. So what do you do?


      What you do - what people facing risk of any kind at any time do - is rely on the affective/instinctive/subconscious system of risk perception that has gotten us this far through evolution’s gauntlet. We take the hints and clues and headlines we have at any given moment and apply a set of heuristics and biases - mental shortcuts - that help us make sense of that partial information. We apply psychological filters that help us judge how scary or not those hints feel. And, oh yeah, we also try to think carefully about the facts.


      In other words, our perception will be a tangled subjective blend of facts and feelings. This messy combination of intellect and instinct shapes our decisions about any risk. Which, of course, sometimes leads to mistakes, which can be risky all by themselves, when we do what feels safe, but isn’t, (like switching to hands free devices when we drive and giving ourselves a reassuring sense of control, which lessens our vigilance, which raises the risk, since talking while you’re driving mostly distracts your brain, not your hand, and that mental distraction is just as bad using a hands-free device as a hand-held one.)


      That’s why this episode is a great teaching moment to highlight the affective nature of the process by which we try to keep ourselves safe. Based on what we know of the specific characteristics or this hidden system, the news for cell phones is not good.



1. The bias of ‘Loss Aversion” means that in a trade off between gain (using the phone) and loss (brain cancer), the loss usually carries more weight. Bad news for phones.



2. The "Availability Heuristic" means that the more aware of something we are, the more worried about it we are. Bad news for phones.



3. "Representativeness bias" means we make sense of partial information by comparing it to what we already know that seems similar. "Radiation" rings a lot of familiar bells. Scary ones.



4. We’re more afraid of human-made risks (radiation from cell phones) than natural ones (radiation from the sun), and we’re more afraid of things that cause high pain and suffering – like brain cancer – than risks which cause less painful outcomes.



5. We worry more about risks produced by sources we don’t trust, like companies which, in service to their profits rather than our health and well being, will undoubtedly say the IARC report does not prove there is any risk. This is counter-productive risk communication, but cell phone companies are not alone in taking this trust-busting approach.




    Not all the risk perception news for cell phones is bad;



1. The more benefit we get from a choice or behavior the more we play DOWN the risk. So you may check who’s calling before deciding whether to risk brain cancer by answering.



2. The more familiar a risk is, and the more everybody’s doing the same thing, and has been for a while, the more we think it’s safe for us to do it, too.




  Risk perception is not a coldly objective process of fact-based analysis. It’s as much gut reaction as it is reason, usually more. Which helps explain why champions of the Cell-Phones-Cause-Cancer Theory will get much louder, and tout the IARC report as the case-closed evidence that proves them right, despite the fact that IARC itself says that’s not so. The fearful nature of the issue explains why the IARC report will almost certainly be used in legal actions against cell phone companies, and in all sorts of marketing by companies that offer protection from The Risk. It explains why the report will be shouted from the rooftops of the 24/7 Scream-a-Thon news media which, if form holds, will play up the ‘cancer” part and play down the “possible” or “limited evidence” or “chance, bias or confounding could not be ruled out with reasonable confidence” parts. And it explains why the heat will be on policy makers to protect us from what we’re afraid of, even if the evidence is far from in on whether there is any real reason to worry.


  Meanwhile, research into the risk will continue to try and answer the question scientifically. And you and I will have to listen to that ringing phone in our purse or pocket, and as it is with all risks, we’ll be guessing, and interpreting, and basically winging it, as we try and figure out how to keep ourselves safe.






About the Author: David Ropeik is an Instructor at the Harvard Extension School and author of How Risky Is It, Really? Why Our Fears Don't Always Match the Facts.






The views expressed are those of the author and are not necessarily those of Scientific American.












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