Levels of doses to radiological workers in Ethiopia: 1977-1988

During the period 1977 to 1988, a total of 10,494 Eastman Kodak Type 2 film badges and 19,236 Vinten lithium fluoride thermoluminescence dosimeters (TLDS) were delivered to medical workers in Ethiopia of which 5,135 (48.93%) film badges and 19,177 (99.69%) TLDS were evaluated. The annual average occupational doses to the workers were estimated to be 1.44 and 4.51 mSv with corresponding collective dose equivalents of 0.29 and 4.51 man-Sv respectively. Comparisons of doses to similar workers in different countries were compiled from the literature. Based on the TLD results and the 1977 International Commission on Radiological Protection (ICRP) risk coefficients it is estimated that the occurrence of extra fatal and non-fatal cancer cases is in the order of 74 per million radiological workers per year. The hereditary defects expected are 18 and 36 cases in the next two and in all future generations respectively. During these periods, the number of institutions monitored rose from 35 to 88 while the workers monitored increased from 100 to 450.