著者
Yuko HIRAI Yoshiaki KODAMA Harry M. CULLINGS Chuzo MIYAZAWA Nori NAKAMURA
出版者
Journal of Radiation Research 編集委員会
雑誌
Journal of Radiation Research (ISSN:04493060)
巻号頁・発行日
pp.1107140221-1107140221, (Released:2011-07-16)
参考文献数
28
被引用文献数
8

The atomic bombs in Hiroshima and Nagasaki led to two different types of radiation exposure; one was direct and brief and the other was indirect and persistent. The latter (so-called exposure to residual radiation) resulted from the presence of neutron activation products in the soil, or from fission products present in the fallout. Compared with the doses from direct exposures, estimations of individual doses from residual radiation have been much more complicated, and estimates vary widely among researchers. The present report bases its conclusions on radiation doses recorded in tooth enamel from survivors in Hiroshima. Those survivors were present at distances of about 3 km or greater from the hypocenter at the time of the explosion, and have DS02 estimated doses (direct exposure doses) of less than 5 mGy (and are regarded as control subjects). Individual doses were estimated by measuring CO2– radicals in tooth enamel with the electron spin resonance (ESR; or electron paramagnetic resonance, EPR) method. The results from 56 molars donated by 49 survivors provided estimated doses which vary from –200 mGy to 500 mGy, and the median dose was 17 mGy (25% and 75% quartiles are –54 mGy and 137 mGy, respectively) for the buccal parts and 13 mGy (25% and 75% quartiles: –49 mGy and 87 mGy, respectively) for the lingual parts of the molars. Three molars had ESR-estimated doses of 300 to 400 mGy for both the buccal and lingual parts, which indicates possible exposures to excess doses of penetrating radiation, although the origin of such radiation remains to be determined. The results did not support claims that a large fraction of distally-exposed survivors received large doses (e.g. 1 Gy) of external penetrating radiation resulting from residual radiation.
著者
Nori NAKAMURA
出版者
Journal of Radiation Research 編集委員会
雑誌
Journal of Radiation Research (ISSN:04493060)
巻号頁・発行日
vol.47, no.SupplementB, pp.B67-B73, 2006 (Released:2006-10-04)
参考文献数
26
被引用文献数
37

Genetic studies in the offspring of atomic bomb survivors have been conducted since 1948 at the Atomic Bomb Casualty Commission and its successor, the Radiation Effects Research Foundation, in Hiroshima and Nagasaki. Past studies include analysis of birth defects (untoward pregnancy outcome; namely, malformation, stillbirth, and perinatal death), chromosome aberrations, alterations of plasma and erythrocyte proteins as well as epidemiologic study on mortality (any cause) and cancer incidence (the latter study is still ongoing). There is, thus far, no indication of genetic effects in the offspring of survivors. Recently, the development of molecular biological techniques and human genome sequence databases made it possible to analyze DNA from parents and their offspring (trio-analysis). In addition, a clinical program is underway to establish the frequency of adult-onset multi-factorial diseases (diabetes mellitus, high blood pressure, and cardiovascular disease etc) in the offspring. The complementary kinds of data that will emerge from this three-pronged approach (clinical, epidemiologic, and molecular aspects) promise to shed light on health effects in the offspring of radiation-exposed people.