Abstract: Abstract: Objective To determine and compare the levels of the certain harmful substances and microbiological levels in the different laboratory animal bedding materials come from the different producing areas and widely used in Beijing region，so as to provide references for constituting local standard of laboratory animal bedding． Method Physical characteristics，and chemical and microbiological pollution levels of different bedding materials were determined according to the methods in force． Result The levels of heavy metals，organophosphorous pesticides， organochlorine pesticides，and other drug residues in corn core and wood shaving bedding materials from different producing areas could meet the requirement of GB 14924. 2-2001． However，microbiological levels in all these bedding materials exceeded the limits to some degree． Conclusion These results can be used as references for constituting local standard of laboratory animal bedding．

Key words: laboratory animal, bedding, physical feature, chemical contamination, microbacteria contamination

摘要： 摘要: 目的对北京地区大量使用的不同材质、不同产地的实验动物垫料进行研究，了解不同材质垫料有害物质水 平，为实验动物垫料地方标准的制定提供参考。方法按照现行方法，对垫料原材料进行物理特性、化学污染物及 微生物污染物水平检测。结果若依据《GB 14924. 2-2001 实验动物配合饲料卫生标准》的规定，各产地的玉米芯 垫料及刨花垫料都符合对重金属、有机磷、有机氯农药及其它有机农药污染的要求，而微生物污染，都有不同程度 的超标。结论本实验结果可作为制定实验动物垫料地方标准的参考。

关键词: 实验动物, 垫料, 物理特性, 化学污染物, 微生物污染物