Health effects of the Chernobyl accidents on the children around the vicinity

The title subject is described for correctly understanding the child health risk in Fukushima under the Nuclear Power Plant Disaster. Pediatric examination conducted by Chernobyl Sasakawa Health and Medical Corporation Project gave the most large-scaled, precise results among studies of those similar projects. The examination after Chernobyl Accident (1986) was performed in May, 1991-Apr., 1996 for children around its vicinity born during the period Apr. 26, 1976-Apr. 26, 1986 by 5 medical facilities located in Belarus, Russia and Ukraine, using the same protocol and similar equipments and reagents. Total number of examinations was 160 thousands and results in 120 thousands subject children were published. In relation to iodine metabolism and possibly to Cs-137, the high incidence (34.66%) of goiter was found and highest incidence of thyroidal node (1.74%) and cancer (0.20%) was found in children in Homyel City in Belarus, particularly of the age 0-5 y. Further detailed studies by authors in the Project revealed that the effect of I-131 exposure on thyroid cancer morbidity was significant with odds ratio 5.5-8.4/Gy. As for leukemia, reported were no strong evidence for the relation between in utero exposure and its incidence, and no supporting data of its relationship with exposure, etc. For non-cancerous diseases, the increased cataract may be related with exposure in children and in the accident-dealing workers, and mental problems may exist in children. Following facts should be taken in consideration when discussing about Fukushima, that 4 kBq of K-40 is contained in human body; it is only pediatric thyroid cancer that increased after the Accident in 270 and 500 thousands residents living in the region with Cs-137 >555 and >37 kBq/m2 ground, respectively; and internal exposure exceeded 50 Bq/kg in 22% of children examined in the Project. (T.T.)