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Published on: April 26, 2014
Comparison of the 1C2 Reference Filtered Cigar to the 1R6F Reference Filtered Cigarette
Amrita Machwe1,2, Samuel B Clark1, Halle Harned1
1Department of Toxicology and Cancer Biology, 1056 V.A. Drive, University of Kentucky College of Medicine, Lexington, KY 40536, United States.
Introduction:
Filtered cigars are a class of tobacco products that can be consumed similarly as conventional cigarettes. Here we have compared tobacco smoke condensates prepared from the 1C2 reference filtered cigar with those from the 1R6F reference cigarette with respect to effects on cell proliferation and viability and AhR-mediated gene expression.
Methods:
Tobacco smoke condensates were prepared using ISO, Health Canada Intense (HCI) or Cigar Smoking (CSR) regimens and certain HPHCs were measured. Cell proliferation and viability assays were performed on immortalized human bronchial or oral epithelial cell lines. AHR-mediated gene expression was measured using a mouse hepatoma cell line engineered to express luciferase under control of the AHR promoter.
Results:
Comparison of different smoking regimens found that the HCI regimen produces higher TPM levels, and higher AhR-mediated gene expression and toxicity when normalized to filler weight. Condensates from 1C2 reference filtered cigars resulted in higher AhR-mediated gene expression and reduced cell viability when compared with condensates prepared under the same conditions from the 1R6F reference cigarettes, again when normalized to filler weight.
Conclusions:
Our results indicate that this reference filtered cigar is somewhat more toxic than the reference cigarette with the HCI regimen being most toxic. Our findings also suggest that some commercial filtered cigars may have at least as strong toxic effects as conventional cigarettes.
Implications:
This study indicates that, if compared by filler weight, the 1C2 reference filtered cigar is more toxic than the 1R6F reference cigarette. Since these products were manufactured based on commercial products and at least some consumers of filtered cigars inhale smoke from these products into the lung, this suggests that some filtered cigars will be at least as harmful to consumers as conventional cigarettes.
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