Furuta Masakazu, Suwa Tomio, Kuwabara Yoshibumi, Otsuhata Kazushige, Takeda Atsuhiko
Research Institute for Advanced Science and Technology, Osaka Prefecture University, 1-2, Gakuen-cho, Sakai, Osaka 599-8570, Japan.
Exp Anim. 2002 Jul;51(4):327-34. doi: 10.1538/expanim.51.327.
Electron beam sterilization for laboratory animal diets was examined as an alternative to 60Co gamma rays. Solid, powder diets for "mice and rats" and solid diets for "rabbits and guinea pigs" which are the main products sterilized by 60Co gamma rays were irradiated with 10-MeV electrons from a linear accelerator at the Research Institute for Advanced Science and Technology, Osaka Prefecture University. At least 20 kGy was required to sterilize the samples irrespective of solid or powder diets, which was in good accordance with the results for 60Co gamma rays. Using a set dose of 30 kGy, a thickness of 45 mm for solid diets and 30 mm for powder diets could be sterilized by "one-sided" irradiation. "Dual-sided" irradiation could sterilize all the solid diets and the powder diets contained in the thicknesses of 90 mm and 75 mm, respectively. Irradiation effects of 10-MeV electrons on the nutrient quality of each diet were almost equivalent to those of 60Co gamma rays. These results suggest that commercially adopted sterilization doses for 60Co gamma rays are applicable to electron sterilization without modification if the depth-dose profile and the minimum dose of irradiated samples are precisely assessed.
对实验室动物饲料的电子束灭菌作为60Co伽马射线的替代方法进行了研究。由60Co伽马射线灭菌的主要产品“小鼠和大鼠”的固体、粉末饲料以及“兔子和豚鼠”的固体饲料，在大阪府立大学先进科学技术研究所，用直线加速器产生的10兆电子伏电子进行辐照。无论固体或粉末饲料，至少需要20千戈瑞来对样品进行灭菌，这与60Co伽马射线的结果非常一致。使用30千戈瑞的设定剂量，固体饲料45毫米的厚度和粉末饲料30毫米的厚度可以通过“单面”辐照进行灭菌。“双面”辐照可以分别对厚度为90毫米和75毫米的所有固体饲料和粉末饲料进行灭菌。10兆电子伏电子对每种饲料营养质量的辐照效果几乎与60Co伽马射线相同。这些结果表明，如果能精确评估深度剂量分布和辐照样品的最小剂量，商业上采用的60Co伽马射线灭菌剂量无需修改即可应用于电子灭菌。
