Toxicological evaluation of an electrically heated cigarette. Part 1: Overview of technical concepts and summary of findings

Abstract

This series of papers provides a description of the toxicological evaluation of an electrically heated cigarette (EHC). With this novel cigarette design the tobacco is heated by a series of electric heating elements, which allows for greater control of the available heat and results in lower temperatures and less combustion compared with conventional lit‐end cigarettes. This design was subjected to testing, including an evaluation of smoke chemistry, in vitro bacterial genotoxicity, in vitro mammalian cell cytotoxicity and a 90‐day smoke inhalation study in rats. A conventional lit‐end cigarette, the University of Kentucky Reference Cigarette 1R4F, was used as a point of comparison in these experiments. When adjusted for the yield of total particulate matter, the EHC delivered 50% lower amounts of about two‐thirds of the 69 smoke constituents measured. Mutagenic activity (Salmonella reverse mutation assay) of the particulate phase material in the presence of metabolic activation was ca. 90% lower, with a slight reduction of activity in the absence of metabolic activation. Cytotoxic activity (neutral red assay) of the particulate phase material was ca. 40% lower, with about equal activity of the gas/vapor‐phase material. Equal activity was noted between cigarette types in a whole smoke rat inhalation assay. The results from this series of tests demonstrate that the EHC produces a much different smoke — with an at least partially reduced yield of smoke constituents and biological activity — from that of a standard reference cigarette. Copyright © 2003 John Wiley & Sons, Ltd.