Technical Report No. 1-88
Analysis of the DS86 atomic bomb radiation dosimetry methods using data on severe epilation
Stram DO, Mizuno SEditor’s note: A publication based on this report was published in Radiat Res 117:93-113, 1989.
Summary
This report presents a reanalysis of the Hiroshima and Nagasaki data on severe epilation as an acute radiation effect using both the new DS86 and the old T65D dosimetries. The report focuses on several aspects of the data which have previously been examined by Jablon et al and Gilbert and Ohara. The report examines the uniformity of epilation-response across shielding category, across sex and age, and in terms of interactions between city, sex, age, and shielding category. It also investigates the apparent relative biological effectiveness (RBE) of neutrons in the DS86 dose compared with the T65D dose, using both within- as well as between-city information. In addition the report discusses evidence for nonlinearity in epilation-response. The epilation- response function exhibits nonlinearity both in terms of a marked increase in slope at about 75 rad, and then, beginning at about 250 rad, a leveling off and eventual decrease in response.
The principal conclusions of the report are as follows. The use of the DS86 dosimetry rather than T65D increases the apparent RBE of neutrons compared with gamma dose from approximately 5 to 10. At these values of RBE the slope of the dose-response, in a middle range from 75-250 rad, is about 165% greater using DS86 than T65D. With respect to the interactions of sex, city, and shielding method, the size and significance of virtually all nonuniformities in epilation-response seen using T65D are also evident with DS86. Additionally it seems difficult to find any evidence that DS86 is an improved predictor of epilation-response over T65D. Finally, the fact that the nonlinearity in dose-response and apparent actual downturn in the epilation rate at the high end of the dose is more striking with DS86 than with T65D is found to be due primarily to the common practice of truncating all T65D doses to 600 rad.
This report presents a reanalysis of the Hiroshima and Nagasaki data on severe epilation as an acute radiation effect using both the new DS86 and the old T65D dosimetries. The report focuses on several aspects of the data which have previously been examined by Jablon et al and Gilbert and Ohara. The report examines the uniformity of epilation-response across shielding category, across sex and age, and in terms of interactions between city, sex, age, and shielding category. It also investigates the apparent relative biological effectiveness (RBE) of neutrons in the DS86 dose compared with the T65D dose, using both within- as well as between-city information. In addition the report discusses evidence for nonlinearity in epilation-response. The epilation- response function exhibits nonlinearity both in terms of a marked increase in slope at about 75 rad, and then, beginning at about 250 rad, a leveling off and eventual decrease in response.
The principal conclusions of the report are as follows. The use of the DS86 dosimetry rather than T65D increases the apparent RBE of neutrons compared with gamma dose from approximately 5 to 10. At these values of RBE the slope of the dose-response, in a middle range from 75-250 rad, is about 165% greater using DS86 than T65D. With respect to the interactions of sex, city, and shielding method, the size and significance of virtually all nonuniformities in epilation-response seen using T65D are also evident with DS86. Additionally it seems difficult to find any evidence that DS86 is an improved predictor of epilation-response over T65D. Finally, the fact that the nonlinearity in dose-response and apparent actual downturn in the epilation rate at the high end of the dose is more striking with DS86 than with T65D is found to be due primarily to the common practice of truncating all T65D doses to 600 rad.