Quantitative risk assessment vs. The whole story?
This paper provides an overviewThis paper provides an overview of the composition of tobacco and tobacco smoke, provides discussion on the various analyses (chemical and toxicological methods) that have been used to assess different products and some of the challenges and weaknesses that have been highlighted in the literature when assessing the “quantitative risk” of complex mixtures such as whole smoke. Currently, no Government or regulatory authority has developed a set of predictive tests whereby one tobacco product can be compared to another, however, the FDA (2012a) has published draft guidance on the broad types of studies required for a modified risk tobacco product “MRTP” application. The mechanisms by which diseases associated with cigarette smoking develop are not fully understood, and there are no agreed animal models for many of these diseases. Epidemiology has been unable to identify cigarette smoke components responsible for diseases in smokers. Likewise, laboratory studies have also been unable to identify such components. Smoking has been associated with multiple diseases and multiple postulated mechanisms, involving many organ systems. It is not appropriate to assess the toxicology of individual cigarette smoke components in isolation through Quantitative Risk Assessment (QRA) methodology. Cigarette smoke is a highly complex mixture consisting of thousands of components and the only appropriate way to assess a combustible tobacco product is to test the whole smoke of such a product in biological assays.