A joint research group consisting of Professor Emeritus Fukumoto of Tohoku University and Assistant Professor Masatoshi Suzuki of the Disaster Reconstruction Research Organization has found the number of blood cells in the blood of wild Japanese monkeys killed in the area around the nuclear power plant after the accident at TEPCO's Fukushima Daiichi Nuclear Power Station. And analyzed the number of blood cells in the bone marrow.As a result, it was found that in adult animals, peripheral blood and the number of blood cells in the bone marrow tend to decrease with the internal exposure dose rate.In addition, Hiroshima University, Tohoku Wildlife Conservation and Management Center, Tokyo Medical University, Niigata University, and Tohoku Medical and Pharmaceutical University participated in the joint research.
In the comprehensive dose assessment project for disaster-affected animals, 95 Japanese macaques (exposed group) killed for adjusting the number of animals in the area around the Fukushima nuclear power plant and XNUMX Japanese macaques (non-exposed group) captured in Miyagi prefecture for comparison. Blood or bone marrow samples were collected and each component was analyzed to investigate the effects of long-term low dose rate radiation exposure.
The internal exposure dose rate was calculated from the radioactive cesium concentration in the skeletal muscle at the time of capture, and the external exposure dose rate was calculated (Note) from the radioactive cesium concentration in the soil at the capture site.As a result, in the case of adults, the white blood cell and platelet counts in the blood and the myeloid cells and megakaryocytes in the bone marrow, which are the sources of these blood cells, showed a negative correlation with the internal dose rate.This suggests that hematopoietic function declines as the internal dose rate of monkeys increases.
To date, no abnormalities have been observed with the naked eye in wild Japanese macaques.The response of the living body to long-term low dose rate radiation exposure is extremely complicated due to habituation and adaptation.Therefore, future changes in blood and bone marrow components shown in this study, and long-term low dose It is necessary to continue follow-up for a long period of time in order to know the effect of internal exposure of the dose rate.
Note: In wild Japanese monkeys in the exposed group, the median internal dose rate is 7.6 μGy / day (minimum 1.9 to maximum 219 μGy / day), and the median external dose rate is 13.9 μGy / day (minimum 6.7 to maximum 35.1 μGy / day). )Met.
Paper information:[Scientific Reports] Haematological analysis of Japanese macaques (Macaca fuscata) in the area affected by the Fukushima Daiichi Nuclear Power Plant accident
