Full body scans, x-rays, and cancer
There's been a lot of talk about full body scans the wake the abortive Christmas Day crotch bombing. Naturally, any of the biggest scanning proponents also sell full body scanners.
A lot of people are nervous about technology that allows TSA screeners to see them naked.
But nobody seems to be asking about the potential health risks of bombarding passengers with x-rays. Not all full body scanners use x-rays, but the TSA has already ordered some that do.
The thing is, X-rays are carcinogenic. That's why your hygienist gives you a lead apron leaves the room when you get dental x-rays.
(Correction: Nevermind about the mammogram example. Thanks to commenters Kittywampus and Butdoctorihatepink for setting me strait.)
No doubt the risks associated with airport screenings are very low, but the relevant question is about the cost/benefit ratio. We shouldn't have to put up with any additional risk unless there's a significant marginal benefit. Even under the status quo, deaths from airplane terrorism are exceedingly rare.
Nate Silver estimates that odds of an air traveler being involved in a terrorist event on any given flight at less than 1 in 10 million. So, if scans caused even a tiny increase in cancer risk among the millions of people who fly every year, the technology could end up killing more people than it saved.
Presumably, it takes a lower dose of x-ray radiation to penetrate clothing than it does to visualize structures deep inside the body. On the other hand, the risks from x-ray exposure are cumulative. Safety guidelines must take into account the risks for frequent fliers. Maybe it's perfectly safe to get scanned once a year, but what if you fly every week? Full-body scans could become an occupational health and safety issue, since so many frequent fliers are traveling for work.
Maybe scanners are perfectly safe. However, these devices should be subject to the same rigorous safety testing as a medical device. We shouldn't just take the word of the high priced hucksters who are touting them on CNN.