I thought it was pretty well known that airline crews do have a detectable increase in cancer rates, as do people who live at high elevations. It's certainly common knowledge among health physicists.

In my humble opinion it is not a good idea to increase the risk, which is why on this board I've often pounded the drum in favor of the pat-down versus the scanner. Those who think a pat-down intrusive probably don't understand how intrusive cancer treatment/chemotherapy is. I don't see the need to increase the risk.