Answer to Question #3909 Submitted to "Ask the Experts"

This may seem like an odd question, but I felt maybe I should ask an expert. As sort of a history buff, a friend mailed me an (unrequested) Soviet Union-era army belt and mailbag from Kiev, Ukraine. These are interesting historical items, but given the nature of the area they might be from—the Ukraine—and the region's exposure to radiation from the Chernobyl disaster, I am wondering if they are safe to handle. Should I dispose of these items (give them to a museum or something) or is my concern about contamination unwarranted?

I would not be concerned about the possible radioactive contamination on your Kiev souvenirs. Radioactive depositions from the Chernobyl accident were quite high in areas near the reactor and extended a long ways to the west and northeast from there, but fallout in the Kiev region was much lower. Deposition on soils in the Kiev region ranges from about 10 to 70 kBq/m² of the "important" radionuclides, ¹³⁷Cs and ⁹⁰Sr. (I have some detailed maps of the contamination in the city of Kiev, and it is really surprisingly spotty.) This is outdoors. I would assume your army belt and mailbag were kept indoors, where deposition was probably 1/10 or less of the outdoor deposition, so they might have 1 to 10 kBq/m². (If you don’t know what a kBq is, don’t worry about it—I’m going to do this as a ratio in a second . . .)

During the days of atmospheric testing of nuclear weapons, quite a bit of ¹³⁷Cs and ⁹⁰Sr were also released into the air and deposited in soils all over the world. The average soil concentration in North America today as a result of that testing in the 1950s and 1960s is about 1 kBq/m² of ⁹⁰Sr and 2 kBq/m² of ¹³⁷Cs. This is about the same as I’ve estimated for your Kiev souvenirs. So in practical terms, they are probably not much more radioactive than the dust from your backyard. I suggest polishing them up and displaying them without concern.

I have been to Kiev and its surroundings a number of times (and collected a few keepsakes myself). I will admit that the first times I went, I took along my little pocket dosimeter and even had a radiation-detecting whole-body examination when I came back; results all indicated no hazard. Kiev is a modern and generally pleasant city of about three million residents, with a lot of recent investment and growth. You can read a really good description of the contamination from the accident (with great color maps), and its possible effects, at the Web site of the United Nations Scientific Committee on the Effects of Atomic Radiation.

Bruce Napier, CHP