Abstract
AIM: To investigate pathologically effects of internal radiation on human body, we determine radioactivity on samples of Nagasaki atomic bomb casualties. We have already investigated methodology of detecting residual radiation on formalin fixed tissue specimens and paraffin-embedded blocks of autopsy cases at acute stage of atomic bomb injury in Nagasaki and Thorotrast patients, who were internally exposed chronic low-dose-rate to alpha-radiation from thorium dioxide deposits following intravascular administration of the radiographic contrast agent. In this study, we determined radioactivity on tissue specimens of Nagasaki atomic bomb causalities at the acute stage injury, Thorotrast patient and non-exposed control subjects by autoradiography. MATERIAL and METHODS: 1) 7 cases of Nagasaki atomic bomb casualties at acute stage radiation injury, 2) 1 case of Thorotrast patient and 3) non-exposed control subjects; 4 cases from Nagasaki Medical Ceneter and 3 cases from Kyusyu university were determined radioactivity in the tissue specimen by autoradiography. The alpha-particle track lengths in the tissue specimen by autoradiopraphy. The alpha-particle track lengths in the tissue specimen were measured. Energy characteristic of 239Pu was calculated from the alpha-particle length in the emulsion by Zeigler's Method, Herium Stopping Powers and Ranges in All Elemental Matter. RESULTS: The much number of alpha-particle tracks from Nagasaki atomic bomb acute casualties was observed on lung, kidney and bone, compared with non-exposed control subjects. The pattern of alpha-particle track lengths of Nagasaki atomic bomb acute casualties was consistent with energy characteristic of 239Pu. It should be identified the nuclide of residual radiation by radiation detector.
