The Possible Occurrence of Nitrosamines in Tobacco Smoke

Attempts were made to demonstrate the presence of N-nitrosamines in tobacco smoke with and without the addition of dimethyl-N-nitrosamine (DMNA) to the smoke stream. In recovery experiments, DMNA, in aqueous solution added to the smoke stream, was recovered to 80 % down to 20 µg, in the presence of the smoke constituents of 50 cigarettes. Extensive Iosses were encountered when organic solvents were used. Up to 500 cigarettes were smoked in one run. In no case could the presence of coloured acyl derivatives corresponding to known nitrosamines be demonstrated. However, in these cases, presence of coloured compounds of non-nitrosamine origin interfered with the estimation of DMNA. It is concluded that nitrosamines do not occur in cigarette smoke in amounts higher than 50 ng per cigarette, and that the actual amounts are probably even lower corresponding to previous reports. The stability of nitrosamines in different solvents will be investigated in some future experiments.