No abstract

Public health officials and tobacco researchers have raised concerns about the possible contributions of additives to the toxicity of cigarettes. However, little attention has been given to the process whereby additives promote initiation and addiction. Levulinic acid is a known cigarette additive. Review of internal tobacco industry documents indicates that levulinic acid was used to increase nicotine yields while enhancing perceptions of smoothness and mildness. Levulinic acid reduces the pH of cigarette smoke and desensitizes the upper respiratory tract, increasing the potential for cigarette smoke to be inhaled deeper into the lungs. Levulinic acid also may enhance the binding of nicotine to neurons that ordinarily would be unresponsive to nicotine. These findings held particular interest in the internal development of ultralight and so-called reduced-exposure cigarette prototypes. Industry studies found significantly increased peak plasma nicotine levels in smokers of ultralight cigarettes following addition of levulinic acid. Further, internal studies observed changes in mainstream and sidestream smoke composition that may present increased health risks. The use of levulinic acid illustrates the need for regulatory authority over tobacco products as well as better understanding of the role of additives in cigarettes and other tobacco products.

The data provided by tobacco manufacturers suggest that the increasing trend in yield is not related to variations in nicotine content but to the yield-to-content ratio, which contradicts their assertions of agricultural variations. Nicotine yield and yield-to-content ratio are controllable features of cigarettes, and they should be monitored and regulated by government agencies.

The number of smokeless tobacco products increased in the Massachusetts market. Further, mean unionised (free) nicotine levels in smokeless tobacco products of several manufacturers continued to rise despite decreasing levels from other manufacturers. The current success in tobacco control is very likely undermined without government surveillance, regulation and widespread public disclosure of nicotine levels in these products.

No abstract