Abstract
Examination of extensive laboratory data collected during the past four decades, particularly considerable unpublished data generated between the mid-1950s and the late 1970s, indicates that none of the materials used as flavorants on smoking tobacco products, particularly cigarettes marketed by a US manufacturer, imparts any significant adverse chemical or biological properties to the mainstream smoke (MSS) from flavorant-treated tobacco, a conclusion reached by Doull et al. (1) in their assessment of available information on nearly 600 ingredients variously used as cigarette tobacco additives in the US Tobacco Industry. In a more recent detailed assessment of the chemical and biological properties reported in the published literature for the MSS from cigarettes fabricated with tobacco with or without one or more additives, Paschke et al. (2) reached a similar conclusion; namely, that in general, no significant increase in the biological activity (carcinogenicity, mutagenicity, and cytotoxicity) of tobacco was reported from cigarettes containing added ingredients. Many flavorful tobacco additives listed by Doull et al. are structurally identical with or similar to highly polar, volatile components identified in the aqueous alcohol-soluble portion of cigarette MSS and tobacco. In the late 1950s, nearly two decades before the precise nature of the aqueous alcohol-soluble components of tobacco was defined, it was determined that their addition to cigarette tobacco produced no significant increase in the cigarette MSS of either the total polycyclic aromatic hydrocarbon (PAH) content or the benzo[a]pyrene (B[a]P) content, MSS components of considerable interest at that time.