Prevention of exposure to N-nitrosamines in the rubber industry: new vulcanization accelerators based on 'safe' amines.

Introduction of 'safe' amino components into traditional accelerator molecules could be an effective measure to prevent formation of carcinogenic N-nitroso compounds during rubber production. About 20 new derivatives of the dithiocarbamate and sulfenamide class, based on 'safe' amines, were synthesized and shown to be suitable for industrial application. Some of the corresponding N-nitrosamines were prepared and investigated for mutagenicity in Salmonella typhimurium TA1535. No or weak mutagenic potential was observed in most cases. The nitrosatability of five sulfenamides derived from 'safe' amines was determined and found to be substantially lower than that of a commercial sulfenamide accelerator tested under identical conditions.