A comparison of the mainstream smoke chemistry and mutagenicity of a representative sample of the US cigarette market with two Kentucky reference cigarettes (K1R4F and K1R5F)

The incorporation of technologies into cigarettes such as filters, filter v entilation, porous cigarette papers, expanded tobacco and reconstituted tob acco sheet has resulted in cigarettes with a wide range of "tar" yields. Th e objectives of this study were to characterize the US cigarette market acc ording to "tar" category (i.e. full Rater, FF; full flavor low tar, FFLT; o r ultra low tar, ULT) and to determine whether the Kentucky reference cigar ettes K1R4F and K1R5F are representative of FFLT and ULT cigarettes, respec tively. As a means of characterization and comparison, the mainstream smoke from a representative sample of commercially available cigarettes from eac h market segment and the K1R4F and K1R5F Kentucky reference cigarettes was analyzed for the presence and level of 18 selected chemical constituents. I n addition, a measure of the mutagenic activity of the mainstream smoke con densate from these cigarettes was determined using an Ames Salmonella mutag enicity. assay. All cigarettes were smoked according to US Federal Trade Co mmission (FTC) guidelines. Results indicated that, overall, mainstream smok e constituent levels are well predicted by FTC "tar" yield-constituent leve ls increased as "tar" delivery increased, Based on the selected analytes me asured in mainstream smoke, the K1R4F reference cigarette was generally rep resentative of the FFLT segment of the US cigarette market. The K1R5F refer ence cigarette was representative of the ULT segment other US cigarette mar ket for cigarettes with "tar" deliveries approximate to it. In terms of mut agenic activity, a direct relationship was also demonstrated on a per cigar ette basis-revertants per cigarette increased with increasing "tar" deliver y. There was a weak tendency (R-square = 0.12, P = 0.08) for specific activ ity (revertants/mg "tar") to increase with decreasing "tar" yield-lower "ta r" products had a slightly higher specific activity, . No significant diffe rences (P > 0.05) were observed when the specific activities of the condens ates from the K1R4F and K1R5F reference cigarettes were compared to the mar ket segments that they were designed to represent, FFLT and ULT, respective ly. Overall, these results support the use of the K1R4F and the K1R5F as ac ceptable reference cigarettes for comparative mutagenicity and smoke chemis try studies of cigarettes available on the US market. (C) 2000 Published by Elsevier Science Ltd.