Abstract
Different approaches have been reported in the literature to reduce the tobacco-specific nitrosamine (TSNA) levels in mainstream smoke (MSS). The reduction of TSNA in the raw tobacco is an approach that has received much attention in recent years. Different elements determine the level of TSNA in MSS: During combustion, part of the TSNA in the cigarette filler can transfer into smoke while another portion can undergo thermal degradation. Moreover, it is possible that TSNA can be pyrosynthesized and that concomitant synergetic effects between the blend components can also occur. Depending on their extent, the formation and degradation of nitrosamines during the combustion process might have an important impact on TSNA level in the smoke of blended cigarettes and might lead to MSS TSNA deliveries which would not parallel that of the blend components.