Investigating predictability of in vitro toxicological assessments of cigarettes: analysis of 7 years of regulatory submissions to Canadian regulatory authorities

A wealth of in vitro toxicological information on different types of tobaccos and tobacco products has been acquired and published, although the link between in vitro data and impact on human health remains elusive. The present study investigates the possibility of establishing quantitative models for the in vitro toxicological endpoint responses to cigarette smoke. To this end, it relies on information submitted to Canadian health authorities during the period 2006-2012. To our knowledge, this is the first time that published results concerning the influence of such factors as cigarette blend, diameter and filter type on in vitro toxicity are confirmed at the level of a representative range of products on a market. Taking these cigarette design features into account and adding a limited amount of quantitative mainstream smoke composition information, it is shown that, within the boundaries of the considered cigarette design parameters, the in vitro toxicological response can be effectively predicted. In vitro tests of tobacco products are an invaluable initial comparative product assessment tool. The present results reveal the limited value of data from repeated tests on products which do not undergo significant modifications.