Mammogram or Airport Scan – Which Is A Higher Radiation Dose?

Normal (left) versus cancerous (right) mammogr...

Image via Wikipedia

There’s been a lot of talk in the news about the value of mammograms. Not so much as a question of their value in finding breast cancers, but more around whether the benefits are really there for doing them. The argument essentially acknowledges that mammography screening does indeed detect cancers and saves lives as a result. But there are many detected cancers where the detection does nothing to change the outcome. And there are lots of small, otherwise undetectable cancers that are benign or too small too matter that result in very invasive procedures.

But what about the radiation load added to the body by having a mammogram done? The way X-ray (or other ‘hard’ radiation) radiation works is that it is essentially cumulative and the effects add up on the body over the course of a lifetime. That means the stray bits of x-ray radiation that filter through the atmosphere, the x-ray for your broken leg, etc. People living at high altitudes and who fly frequently get higher exposure. As do people working as x-ray technicians.

Mammography involves a relatively high exposure to radiation – about four times as high as a chest x-ray. But even that level of radiation isn’t seen as significant in the grand scheme of things.

So how about screening at the airport? For frequent flyers that happens a LOT more often than an annual mammogram. A recent report by ProPublica that is extremely thorough and even handed takes a look at the truly scandalous lack of oversight into how the new backscatter x-ray screening technology was put in place and the complete lack of awareness or interest in whether the machines are operating as they should. That is a real scandal. But having said that, if we assume that they ARE operating right then the average person doesn’t have a lot to worry about. The range of claimed radiation ranges from 1/4000th as much radiation as a mammogram to as high as about one one hundredth of the radiation in a mammogram. Even taking the higher number you would have to be flying a truly remarkable amount for airport screenings to worry you as much as an annual mammogram. Interestingly, the article does point out that pregnant pilots and aircraft staff are advised to change their flying habits to lessen radiation exposure – so the cumulative effect of many times a week screening plus the higher level of exposure while flying must add up. No such warning is given to pregnant frequent flyers, however. And what about a malfunctioning unit? – it sounds like they don’t get tested very often.

Nevertheless, the bottom line is mammograms have a significantly higher level of radiation by a wide margin. Just remember that radiation is additive and the flight itself piles radiation insult onto the scanner’s injury.

Comments are closed.