Health Risks of X-Rays

There have been alarmist and often sensationalist stories about the health effects of ionizing radiation since it was first discovered. Wilhelm Conrad Röntgen won the Nobel prize in Physics in 1901 for his discovery of X-rays, and it was quickly discovered that over-exposure to X-rays was dangerous. Marie Curie – the Polish-born French scientist who won two Nobel prizes in 1903 and 1911 – died of leukemia. It has often been suspected that it was related to her long-term exposure to radiation.

As a child growing up in England, many shoe shops had primitive X-ray devices called fluoroscopes to allow kids and their parents to look at their little toes inside their shoes. Despite knowledge of the health effects of X-rays I reported in an article published fifteen years ago, that while working at a hospital in Nanjing, China, I was shocked that the ancient X-ray equipment had no shielding at all.

There is no doubt that X-rays and their more sophisticated progeny, like CT scans, have revolutionized medicine, and saved countless lives. So how do we weight the risks and benefits of diagnostic X-rays? The last thing that we want to do is to discourage people from having the medical help that they need.

Help has arrived in a new report Health Risks from Exposure to Low Levels of Ionizing Radiation: BEIR VII Phase 2 from the National Academy of Science, published in September 2005. I think that this report should be considered the definitive and authoritative resource on the subject of radiation risk.

Dr. Richard C. Semelka has produced an outstandingly helpful summary of the report and its key recommendations.
1.    The report says that medical X-rays can cause cancer, and that there is no safe lower limit. The risk is very low, and, as one might imagine, is higher in children. It is also important to be aware that cancers are not uncommon and almost always have multiple causes, so claiming a causal link between a diagnostic X-ray examination and the subsequent development of a tumor is very difficult. The main tumors said to be associated with X-rays are leukemia, thyroid and breast. The time between exposure and tumor development can be very long.
2.    Therefore any use of X-rays, particularly CT scanning should be done judiciously. One of the problems in the United States is that many professionals have been forced to practice defensive medicine. They could be held legally liable if they do not do a test.
3.    Professionals already use the lowest possible dose of radiation.
4.    Professionals are already discussing whether there are any possibilities of substituting other types of diagnostic imaging.

Now I’m going to tell you a story. Some time ago I had a health problem that may well have been a result of exposure to radiation as a child. The health problem is now long gone, but it sensitized me to the issue. So what would I do now if a physician recommended that I have an X-ray or a CT scan? I would discuss the options:
How important is the test?
What would be the downside of not having it?
Is there any other way of getting the same answer without using X-rays?
If the answer to that one is “no, “ then what’s the lowest dose of radiation that we can use?
And how can we shield the bits of me that don’t need a dose of X-rays?
Then, even with my medical history, I personally would almost certainly go ahead and have the test. But every person would be well advised to have that discussion with their health care provider.

Many professionals read my articles, and for you, it would be worth considering getting the report, and going through Dr. Semelka’s thoughtful article.

I think it’s excellent that scientists have produced this report and that thoughtful radiologists around the world are working on the best ways of safe guarding the welfare of the public. I am going to continue to report the emerging scientific literature on this important topic.

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