PURPOSE: To obtain a rubber composition capable of preventing nitrosamine from occurring in producing rubber products by adding tetrakis(2-ethylhexyl) thiuram disulfide and a vulcanization accelerator to an acrylonitrile-butadiene copolymer rubber (NBR).

CONSTITUTION: This NBR composition is obtained by blending (A) 100 pts.wt. acrylonitrile.butadiene copolymer rubber (NBR) with (B) 0.5-10 pts.wt. tetrakis(2- ethylhexyl)thiuram disulfide and (C) one or more vulcanization accelerators such as benzothiazole-based, sylfenamide-based, dithiocarbamate-based, guanidine- based, aldehyde.ammonia-based, aldehyde.amine-based, thiourea-based, xanthate- based and dithiophosphate-based vulcanization accelerators in an amount so as to provide 1-10 pts.wt. total amount of the vulcanization accelerators. This composition is capable of preventing nitrosamine which is a carcinogenic substance from occurring in a working environment related to the production of rubber products.