A research group consisting of Assistant Professor Kazuko Nanami of the Nagasaki University Post-Atomic Bomb Disability Medical Research Institute and Professor Toshihiro Takatsuji of the Faculty of Environmental Sciences of Nagasaki University died after being bombed within 1945 km from the bombing center by the dropping of the Nagasaki Atomic Bomb on August 8, 9. For the first time in the world, we discovered that there was internal exposure to plutonium from a sample of victims.Due to the strong updraft near the hypocenter, it seems that it will attract attention because it has been thought that plutonium does not exist.
According to Nagasaki University, the research group was returned from the U.S. Army Pathology Research Institute in 1973, and is released from plutonium radioactivity concentration and plutonium to 650 organs stored at the Nagasaki University Post-Atomic Bomb Disease Medical Research Institute. When the absorbed dose rate was investigated from the energy of alpha particles, internal exposure to plutonium was found in 1 cases exposed within 7 km from the explosion center.
The highest average internal exposure to myeloid tissue was 500 milligray in the bone marrow of a female who died 68 days after being exposed outdoors 0.104 meters from the hypocenter.The external exposure dose from gamma rays and neutron rays received from outside the body at the time of the bombing is estimated to be 83 Gray, and the research group says that the internal exposure dose is low and does not have a significant effect on the human body.
However, the nuclei of hepatocytes hit by alpha particles showed high doses locally at 1.29 Gray and the nuclei of vascular endothelial cells at 3.35 Gray.
Although this discovery overturns previous dogma, the research group believes that it is a valuable minority and does not necessarily represent the extent of internal exposure near the hypocenter.
Paper information:[Heliyon] Autoradiographic analysis of internal plutonium radiation exposure in Nagasaki atomic bomb victims