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An experimental method to study emissions from heated tobacco between 100-200°C.

Forster M, Liu C, Duke MG, McAdam KG, Proctor CJ - Chem Cent J (2015)

Bottom Line: Some studies have shown that heating tobacco to temperatures below pyrolysis and combustion temperatures has the potential to reduce or eliminate some toxicants found in cigarette smoke.These results demonstrate the practical utility of this tool to study low-temperature toxicant formation and emission from heated tobacco.Between 100 to 200°C, nicotine and some cigarette smoke compounds were released as a result of evaporative transfer or initial thermal decomposition from the tobacco blend.

View Article: PubMed Central - PubMed

Affiliation: GR&D Centre, British American Tobacco, Regents Park Road, Southampton, SO15 8TL UK.

ABSTRACT

Background: Cigarette smoke emissions are mainly produced by distillation, pyrolysis and combustion reactions when the tobacco is burnt. Some studies have shown that heating tobacco to temperatures below pyrolysis and combustion temperatures has the potential to reduce or eliminate some toxicants found in cigarette smoke. In this study, we designed a bench-top tube furnace that heats tobacco between 100-200°C and systematically studied the effects of heating temperatures on selected gas phase and aerosol phase compounds using an ISO machine-smoking protocol.

Results: Among a list of target chemical compounds, seven toxicants (nicotine, carbon monoxide, acetaldehyde, crotonaldehyde, formaldehyde, NNN and NNK) were quantifiable but not at all temperatures examined. The levels of the compounds generally displayed an increasing trend with increasing temperatures. The observed carbon monoxide and aldehydes represented the initial thermal breakdown products from the tobacco constituents. Water was the largest measured component in the total aerosol phase collected and appeared to be mainly released by evaporation; nicotine release characteristics were consistent with bond breaking and evaporation. Quantifiable levels of NNK and NNN were thought to be the result of evaporative transfer from the tobacco blend.

Conclusions: These results demonstrate the practical utility of this tool to study low-temperature toxicant formation and emission from heated tobacco. Between 100 to 200°C, nicotine and some cigarette smoke compounds were released as a result of evaporative transfer or initial thermal decomposition from the tobacco blend.

No MeSH data available.


Related in: MedlinePlus

TGA of tobacco heated in air at three heating rates.
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Fig1: TGA of tobacco heated in air at three heating rates.

Mentions: The TGA results up to 300°C are plotted in Figure 1. The rate of weight loss (−dG/dT) began with a significant weight loss up to 100°C due to the release of free or physically bound water, with a second major weight loss occurring over a relatively broad temperature range above ca. 200°C. The water loss around 100°C accounted for approximately 7% of the weight loss. At the end of 200°C, the samples had lost about 17% of their initial weight which was more than the 11% moisture content, suggesting thermal evaporation and possibly onset of some initial thermal decomposition of some tobacco constituents [16,18,19]. The heating rates used in Figure 1 are significantly slower than those typically found in a burning cigarette during a puff where the tobacco heating rate can exceed a few hundred degrees per second [1]. Within the range of heating rates studied, there was no discernable weight loss trend in Figure 1, however, the 1st derivative of the weight loss showed a temporary plateau around 100°C and a gentle reflection point between 280 to 320°C.Figure 1


An experimental method to study emissions from heated tobacco between 100-200°C.

Forster M, Liu C, Duke MG, McAdam KG, Proctor CJ - Chem Cent J (2015)

TGA of tobacco heated in air at three heating rates.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4418098&req=5

Fig1: TGA of tobacco heated in air at three heating rates.
Mentions: The TGA results up to 300°C are plotted in Figure 1. The rate of weight loss (−dG/dT) began with a significant weight loss up to 100°C due to the release of free or physically bound water, with a second major weight loss occurring over a relatively broad temperature range above ca. 200°C. The water loss around 100°C accounted for approximately 7% of the weight loss. At the end of 200°C, the samples had lost about 17% of their initial weight which was more than the 11% moisture content, suggesting thermal evaporation and possibly onset of some initial thermal decomposition of some tobacco constituents [16,18,19]. The heating rates used in Figure 1 are significantly slower than those typically found in a burning cigarette during a puff where the tobacco heating rate can exceed a few hundred degrees per second [1]. Within the range of heating rates studied, there was no discernable weight loss trend in Figure 1, however, the 1st derivative of the weight loss showed a temporary plateau around 100°C and a gentle reflection point between 280 to 320°C.Figure 1

Bottom Line: Some studies have shown that heating tobacco to temperatures below pyrolysis and combustion temperatures has the potential to reduce or eliminate some toxicants found in cigarette smoke.These results demonstrate the practical utility of this tool to study low-temperature toxicant formation and emission from heated tobacco.Between 100 to 200°C, nicotine and some cigarette smoke compounds were released as a result of evaporative transfer or initial thermal decomposition from the tobacco blend.

View Article: PubMed Central - PubMed

Affiliation: GR&D Centre, British American Tobacco, Regents Park Road, Southampton, SO15 8TL UK.

ABSTRACT

Background: Cigarette smoke emissions are mainly produced by distillation, pyrolysis and combustion reactions when the tobacco is burnt. Some studies have shown that heating tobacco to temperatures below pyrolysis and combustion temperatures has the potential to reduce or eliminate some toxicants found in cigarette smoke. In this study, we designed a bench-top tube furnace that heats tobacco between 100-200°C and systematically studied the effects of heating temperatures on selected gas phase and aerosol phase compounds using an ISO machine-smoking protocol.

Results: Among a list of target chemical compounds, seven toxicants (nicotine, carbon monoxide, acetaldehyde, crotonaldehyde, formaldehyde, NNN and NNK) were quantifiable but not at all temperatures examined. The levels of the compounds generally displayed an increasing trend with increasing temperatures. The observed carbon monoxide and aldehydes represented the initial thermal breakdown products from the tobacco constituents. Water was the largest measured component in the total aerosol phase collected and appeared to be mainly released by evaporation; nicotine release characteristics were consistent with bond breaking and evaporation. Quantifiable levels of NNK and NNN were thought to be the result of evaporative transfer from the tobacco blend.

Conclusions: These results demonstrate the practical utility of this tool to study low-temperature toxicant formation and emission from heated tobacco. Between 100 to 200°C, nicotine and some cigarette smoke compounds were released as a result of evaporative transfer or initial thermal decomposition from the tobacco blend.

No MeSH data available.


Related in: MedlinePlus