Endo K, Koizumi M, Kinoshita F, Nakazawa K
Kaku Igaku. 1999 Dec;36(9):1023-31.
Radiation safety management condition in Japanese nuclear medicine facilities were investigated by the questionnaire method. The first questionnaire was asked in all Japanese 1,401 Nuclear Medicine facilities. Answers from 624 institutes (44.5%) were received and analyzed. The radiation-safety management in nuclear medicine institutes was considered to be very well performed everyday. Opinion for the present legal control of nuclear medicine institutes was that the regulation in Japan was too strict for the clinical use of radionuclides. The current regulation is based on the assumption that 1% of all radioactivity used in nuclear medicine institutes contaminates into the draining-water system. The second questionnaire detailing the contamination of radioactivity in the draining-water system was sent to 128 institutes, and 64 answers were received. Of them, 42 institutes were considered to be enough to evaluate the contamination of radioactivity in the draining-water system. There was no difference between 624 institutes answered to the first questionnaire and 42 institutes, where the radioactivity in the draining-water system was measured, in the distribution of the institute size, draining-water system equipment and the radioactivity measuring method, and these 42 institutes seemed to be representative of Japanese nuclear medicine institutes. Contamination rate of radioactivity into the draining system was calculated by the value of radioactivity in the collecting tank divided by the amount of radionuclides used daily in each institute. The institutes were divided into two categories on the basis of nuclear medicine practice pattern; type A: in-vivo use only and type B: both in-vivo and in-vitro use. The contamination rate in 27 type A institutes did not exceed 0.01%, whereas in 15 type B institutes the contamination rate distributed widely from undetectable to above 1%. These results indicated that the present regulation for the draining-water system, which assumed that 1% of all radioactivity used in nuclear medicine institutes contaminated into draining-water system, should be reconsidered in nuclear medicine facilities where radionuclides are used only in in-vivo studies.
通过问卷调查法对日本核医学设施的辐射安全管理状况进行了调查。向日本全国1401家核医学设施发放了第一份问卷。收到了624家机构（44.5%）的回复并进行了分析。核医学机构的辐射安全管理在日常工作中被认为执行得非常好。对于目前对核医学机构的法律管控，意见是日本的规定对于放射性核素的临床使用过于严格。现行规定基于这样的假设，即核医学机构使用的所有放射性物质中有1%会污染排水系统。第二份详细询问排水系统放射性污染情况的问卷被发送给128家机构，收到了64份回复。其中，42家机构被认为足以评估排水系统中的放射性污染情况。回答第一份问卷的624家机构与测量排水系统放射性的42家机构在机构规模、排水系统设备和放射性测量方法的分布上没有差异，这42家机构似乎代表了日本核医学机构。排水系统的放射性污染率通过收集罐中的放射性值除以各机构每日使用的放射性核素量来计算。根据核医学实践模式将这些机构分为两类：A类：仅用于体内使用；B类：体内和体外使用都有。27家A类机构的污染率不超过0.01%，而15家B类机构的污染率分布广泛，从检测不到到超过1%。这些结果表明，对于仅在体内研究中使用放射性核素的核医学设施，应重新考虑目前关于排水系统的规定，该规定假设核医学机构使用的所有放射性物质中有1%会污染排水系统。
