Limits...
Approaches for the design of reduced toxicant emission cigarettes.

Dittrich DJ, Fieblekorn RT, Bevan MJ, Rushforth D, Murphy JJ, Ashley M, McAdam KG, Liu C, Proctor CJ - Springerplus (2014)

Bottom Line: This study examined the effect of modifications to filter ventilation, variations in cigarette circumference and active charcoal filter length and loading, as well as combinations of these features in a reduced-toxicant prototype (RTP) cigarette, on the yields of toxicants in cigarette smoke.For higher ISO tar level cigarettes, however, there were no significant reductions in MLE.Split-tipping was combined with optimal filter length and cigarette circumference in an RTP cigarette that gave significantly lower mainstream (up to ~90%) and sidestream (predominately 20%-60%) smoke yields of numerous toxicants as compared with a commercial comparator cigarette under machine-smoking conditions.

View Article: PubMed Central - PubMed

Affiliation: British American Tobacco, Group Research & Development, Regents Park Road, Millbrook, Southampton SO15 8TL UK.

ABSTRACT
Cigarette smoking causes serious diseases through frequent and prolonged exposure to toxicants. Technologies are being developed to reduce smokers' toxicant exposure, including filter adsorbents, tobacco treatments and substitutes. This study examined the effect of modifications to filter ventilation, variations in cigarette circumference and active charcoal filter length and loading, as well as combinations of these features in a reduced-toxicant prototype (RTP) cigarette, on the yields of toxicants in cigarette smoke. An air-dilution mechanism, called split-tipping, was developed in which a band of porous paper in the centre of the filter tipping functions to minimise the loss of effective filter ventilation that occurs at the high flow rates encountered during human-smoking, and to facilitate the diffusional loss of volatile toxicants. As compared with conventional filter ventilation cigarettes, split-tipping reduced tar and volatile smoke constituent emissions under high flow rate machine-smoking conditions, most notably for products with a 1-mg ISO tar yield. Furthermore, mouth level exposure (MLE) to tar and nicotine was reduced among smokers of 1-mg ISO tar cigarettes in comparison to smokers of cigarettes with traditional filter ventilation. For higher ISO tar level cigarettes, however, there were no significant reductions in MLE. Smaller cigarette circumferences reduced sidestream toxicant yields and modified the balance of mainstream smoke chemistry with reduced levels of aromatic amines and benzo[a]pyrene but increased yields of formaldehyde. Smaller circumference cigarettes also had lower mainstream yields of volatile toxicants. Longer cigarette filters containing increased levels of high-activity carbon (HAC) showed reduced machine-smoking yields of volatile toxicants: with up to 97% removal for some volatile toxicants at higher HAC loadings. Split-tipping was combined with optimal filter length and cigarette circumference in an RTP cigarette that gave significantly lower mainstream (up to ~90%) and sidestream (predominately 20%-60%) smoke yields of numerous toxicants as compared with a commercial comparator cigarette under machine-smoking conditions. Significantly lower mainstream and sidestream smoke toxicant yields were observed for an RTP cigarette comprising several toxicant reducing technologies; these observations warrant further evaluation in clinical studies where real-world relevance can be tested using biomarkers of exposure and physiological effect.

No MeSH data available.


Related in: MedlinePlus

Influence of cigarette tobacco weight on ISO sidestream yields of toxicants from Canadian cigarettes (Health Canada2004).
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Related In: Results  -  Collection

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Fig3: Influence of cigarette tobacco weight on ISO sidestream yields of toxicants from Canadian cigarettes (Health Canada2004).

Mentions: For a fixed length cigarette, tobacco mass can be reduced by decreasing either the tobacco packing density or the circumference. In addition to influencing smoke yields, however, significantly reducing the tobacco packing density can affect the integrity of the tobacco rod, puff number and pressure drop (Health Canada2004), each of which can affect product quality and acceptability among consumers. We first examined the influence of tobacco weight on sidestream smoke yields using data submitted to Health Canada in 2004 (Health Canada2004). FigureĀ 3 shows that sidestream toxicant yields increase with increasing tobacco mass for some analytes (tar, nicotine, CO, 2-aminonaphthalene, 4-aminobiphenyl, benzo[a]pyrene, all measured carbonyls, cresols and isoprene); however, the sidestream yields of other analytes were found to decrease with increasing tobacco mass (e.g. TSNAs, HCN, 1-aminonaphthalene, 3-aminobiphenyl, NO, and a number of volatile species). Thus, although tobacco weight influences the yield of sidestream smoke from cigarettes, other factors strongly contribute to individual toxicant yields. The cigarettes in the Health Canada dataset represent various tobacco blends (although the great majority, but not all, of the blends will be flue-cured in nature) and cigarette constructions, for which little information is available. The impact on this is most apparent for species such as TSNAs, whose yields in smoke are highly dependent on their levels in the tobacco blend (Baker1999).Figure 3


Approaches for the design of reduced toxicant emission cigarettes.

Dittrich DJ, Fieblekorn RT, Bevan MJ, Rushforth D, Murphy JJ, Ashley M, McAdam KG, Liu C, Proctor CJ - Springerplus (2014)

Influence of cigarette tobacco weight on ISO sidestream yields of toxicants from Canadian cigarettes (Health Canada2004).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4125608&req=5

Fig3: Influence of cigarette tobacco weight on ISO sidestream yields of toxicants from Canadian cigarettes (Health Canada2004).
Mentions: For a fixed length cigarette, tobacco mass can be reduced by decreasing either the tobacco packing density or the circumference. In addition to influencing smoke yields, however, significantly reducing the tobacco packing density can affect the integrity of the tobacco rod, puff number and pressure drop (Health Canada2004), each of which can affect product quality and acceptability among consumers. We first examined the influence of tobacco weight on sidestream smoke yields using data submitted to Health Canada in 2004 (Health Canada2004). FigureĀ 3 shows that sidestream toxicant yields increase with increasing tobacco mass for some analytes (tar, nicotine, CO, 2-aminonaphthalene, 4-aminobiphenyl, benzo[a]pyrene, all measured carbonyls, cresols and isoprene); however, the sidestream yields of other analytes were found to decrease with increasing tobacco mass (e.g. TSNAs, HCN, 1-aminonaphthalene, 3-aminobiphenyl, NO, and a number of volatile species). Thus, although tobacco weight influences the yield of sidestream smoke from cigarettes, other factors strongly contribute to individual toxicant yields. The cigarettes in the Health Canada dataset represent various tobacco blends (although the great majority, but not all, of the blends will be flue-cured in nature) and cigarette constructions, for which little information is available. The impact on this is most apparent for species such as TSNAs, whose yields in smoke are highly dependent on their levels in the tobacco blend (Baker1999).Figure 3

Bottom Line: This study examined the effect of modifications to filter ventilation, variations in cigarette circumference and active charcoal filter length and loading, as well as combinations of these features in a reduced-toxicant prototype (RTP) cigarette, on the yields of toxicants in cigarette smoke.For higher ISO tar level cigarettes, however, there were no significant reductions in MLE.Split-tipping was combined with optimal filter length and cigarette circumference in an RTP cigarette that gave significantly lower mainstream (up to ~90%) and sidestream (predominately 20%-60%) smoke yields of numerous toxicants as compared with a commercial comparator cigarette under machine-smoking conditions.

View Article: PubMed Central - PubMed

Affiliation: British American Tobacco, Group Research & Development, Regents Park Road, Millbrook, Southampton SO15 8TL UK.

ABSTRACT
Cigarette smoking causes serious diseases through frequent and prolonged exposure to toxicants. Technologies are being developed to reduce smokers' toxicant exposure, including filter adsorbents, tobacco treatments and substitutes. This study examined the effect of modifications to filter ventilation, variations in cigarette circumference and active charcoal filter length and loading, as well as combinations of these features in a reduced-toxicant prototype (RTP) cigarette, on the yields of toxicants in cigarette smoke. An air-dilution mechanism, called split-tipping, was developed in which a band of porous paper in the centre of the filter tipping functions to minimise the loss of effective filter ventilation that occurs at the high flow rates encountered during human-smoking, and to facilitate the diffusional loss of volatile toxicants. As compared with conventional filter ventilation cigarettes, split-tipping reduced tar and volatile smoke constituent emissions under high flow rate machine-smoking conditions, most notably for products with a 1-mg ISO tar yield. Furthermore, mouth level exposure (MLE) to tar and nicotine was reduced among smokers of 1-mg ISO tar cigarettes in comparison to smokers of cigarettes with traditional filter ventilation. For higher ISO tar level cigarettes, however, there were no significant reductions in MLE. Smaller cigarette circumferences reduced sidestream toxicant yields and modified the balance of mainstream smoke chemistry with reduced levels of aromatic amines and benzo[a]pyrene but increased yields of formaldehyde. Smaller circumference cigarettes also had lower mainstream yields of volatile toxicants. Longer cigarette filters containing increased levels of high-activity carbon (HAC) showed reduced machine-smoking yields of volatile toxicants: with up to 97% removal for some volatile toxicants at higher HAC loadings. Split-tipping was combined with optimal filter length and cigarette circumference in an RTP cigarette that gave significantly lower mainstream (up to ~90%) and sidestream (predominately 20%-60%) smoke yields of numerous toxicants as compared with a commercial comparator cigarette under machine-smoking conditions. Significantly lower mainstream and sidestream smoke toxicant yields were observed for an RTP cigarette comprising several toxicant reducing technologies; these observations warrant further evaluation in clinical studies where real-world relevance can be tested using biomarkers of exposure and physiological effect.

No MeSH data available.


Related in: MedlinePlus