Answer to Question #5322 Submitted to "Ask the Experts"

I was stationed on a floating dry dock in the Navy from 1978 to 1980. The ship docked submarines for routine maintenance and my job was working up in the sub replacing zincs that attract salt from the water. I received an accumulative dose of 15 rem to the whole body. I am now having a lot of medical problems, some precancerous and abnormal or rare. I know I have a serious problem on my hands, but what are my chances of getting cancer if I don't keep up very extensive preventive measures?

Your radiation dose of 15 rem in three years did not exceed the recommended occupational dose limit of the National Council on Radiation Protection and Measurements. That limit is 5 rem per year. The likelihood of adverse effect from that dose is at worst extremely small and most likely zero. Radiation-induced cancer is quite rare. Of the approximately 100,000 Japanese atomic bomb survivors, thousands died of cancer but only a few  hundred could be attributed to radiation. Radiation mimics nature, and  there is no known way to determine whether a given cancer was radiation-induced or arose spontaneously. The American Cancer Society has estimated that about one American in every two or three gets cancer. In contrast, the probability of cancer induced by your occupational radiation dose is vanishingly small.

S. Julian Gibbs, DDS, PhD