Answer to Question #4293 Submitted to "Ask the Experts"

In 1953, when I was three to four months old, I was treated with radium for a birthmark on the bridge of my nose. Because of my young age and the location of the birthmark near my eyes, my mother held me on her lap during the three to four treatments I had. In 1963, my mother had a large tumor on her thyroid removed. In 1988 I toured a nuclear power facility with a group of science teachers. When I walked through the radiation detection alarm system at the end of the tour I set off the alarm. In 1997, I had a basal cell carcinoma removed from the bridge of my nose. I have three questions:

1. Is it possible that radioactive decay from treatments I received in 1953 set off the detection alarm system?

2. If this is possible, how much radiation would be necessary and from where is it coming?

3. Is the radiation exposure the same throughout my body or concentrated in the region of my head and neck?

In the 1950s, radiation treatment for vascular birthmarks (for example, hemangiomas) included permanent interstitial implants of radon seeds or placement over the lesion of a moulage (mold) into which radium sources had been introduced. Typically, radon seeds were thin gold tubes into which radon gas was pumped and the ends sealed. Because of the way that radon undergoes radioactive transformations, after a few months the amount of radioactivity will be a fraction of a percent of the initial amount. Because of this, radon tubes could be permanently placed in the lesion being treated. The small amount of remaining radioactivity would be from a lead isotope (²¹⁰Pb) with a relatively long half-life (22 years) and its byproducts. 

When a moulage was used, a sealed radium source would be fitted into the moulage. Sealed radium sources came in various shapes. See the Oak Ridge Associated Universities website for examples. The moulage would be placed over the lesion for prescribed periods of time. Based on your description, this is most likely the treatment you received. As long as the integrity of the seal was not compromised, no radium would have escaped and you would not have any radioactivity in you from the treatment. It was uncommon, but not unheard of for radium sources to leak. Sealed sources were (and are) routinely tested for leakage. If found leaking, they are removed from service and disposed. 

Radium acts similarly to calcium in the body—it is taken up in bone. Once there, it tends to be replaced slowly. 

With this background in mind, let's answer your specific questions: 

1. Is it possible that radioactive decay from treatments I received in 1953 set off the detection alarm system?

It is possible, but highly unlikely, that you had residual radioactivity from the 1953 treatments. For this to be the case, the sources used in your treatment would need to be leaking radium.   

2. If this is possible, how much radiation would be necessary and from where is it coming? 

This would depend on the power plant's radiation detection system. They can detect individuals with small amounts of radioactive material from recent nuclear medicine procedures. 

3. Is the radiation exposure the same throughout my body or concentrated in the region of my head and neck?

The radium would be taken up by bone throughout the body. 

In correspondence we had in addition to your initial questions you asked: 

4. Can I have a test done to determine if I have high radiation somewhere? 

There are ways to measure uptakes of radioactivity from a simple survey with a hand-held radiation detector to sophisticated whole-body counters. 

5. I experienced sharp pain at the base of my spine almost as soon as I stood up after a scan for osteoporosis. Is it possible that higher-than-normal radiation levels in my body might affect my body's reactions to medical levels of radiation?

No. Bone density measurements use low-energy x rays and deliver low-radiation doses. These would not trigger an acute painful reaction even if you had higher-than-normal levels of radioactivity in the bone. Radiation levels high enough to cause acute pain would cause severe damage (severe reddening, ulcerations, and necrosis) to your skin as well. 

You should be aware that the basal cell carcinoma removed from your nose could have been a result of the initial treatment and not due to any lingering radioactivity. Or it could have been caused by exposure to ultraviolet radiation (remember that sunburn when you were a teenager?) especially if you have a fair skin complexion. 

Kent Lambert, MS, CHP

Acknowledgement:  Luther W. Brady, MD, provided information on standards of practice for radiation treatments of birthmarks in the 1950s.