原爆幸存者的甲状腺疾病随访调查往往忽略了原爆放射性落下灰的效应.日本西山(Nishiyama)地区虽因山脉遮挡而未直接受到原爆辐射,但是接受到落下灰.1969年研究表明,该地区的泥土中~(137)Cs放射性比非尘埃地区高一倍,居民全身放射性增高.作者对原爆后在这一地区居住至少10年并仍住 Surveillance of thyroid disease in primary blast survivors often overlooks the radioactive fallout of the primary blast, although the Nishiyama region of Japan was not directly exposed to the blast of atomic radiation because of the mountain cover but received ashes. In 1969, studies showed that the soil The radioactivity of ~ (137) Cs is twice as high as that of non-dusty area, and the whole body radioactivity is increased. The author resides in this area for at least 10 years after the original explosion and still lives