Regulatory toxicology and pharmacology : RTP
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Regul. Toxicol. Pharmacol. · Dec 2011
Comparative StudyMouth level smoke exposure using analysis of filters from smoked cigarettes: a study of eight countries.
The analysis of spent cigarette filters enables the estimation of the nicotine and tar (nicotine-free dry particulate matter) yields obtained by smokers in their everyday environment and has been shown to correlate well with biomarkers of exposure. Leading products across the range of ISO tar yields were selected from Australia, Brazil, Canada, Germany, Japan, New Zealand, South Africa and Switzerland. At least fifty demographically representative smokers were recruited per product. ⋯ Male smokers obtained higher mean estimated tar and nicotine exposures than female smokers. These gender differences were statistically significant for six countries. Significant correlations were found between estimated nicotine exposure and ISO nicotine yield, and between estimated tar exposure and ISO tar yield (p<0.001).
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Regul. Toxicol. Pharmacol. · Dec 2011
Comparative StudyEstimation and correlation of cigarette smoke exposure in Canadian smokers as determined by filter analysis and biomarkers of exposure.
A clinical study conducted in Canada compared two methods of estimating exposure to cigarette smoke in 192 volunteer subjects: 43 smokers of 4-6 mg, 49 of 8-12 mg and 50 of 14-15 mg ISO tar yield cigarettes and 50 non-smokers. Estimates of mouth level exposure (MLE) to nicotine, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), pyrene and acrolein were obtained by chemical analysis of spent cigarette filters. Estimates of smoke constituent uptake were achieved by analysis of urinary biomarkers for total nicotine equivalents (nicotine, cotinine, trans-3'-hydroxycotinine plus their glucuronide conjugates), NNK (total 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) plus glucuronide), pyrene (1-hydroxy pyrene plus glucuronide) and acrolein (3-hydroxylpropyl-mercapturic acid) plus the nicotine metabolite cotinine in plasma and saliva. ⋯ Unexpectedly high levels of acrolein biomarker found in non-smokers urine on one of the two days sampled emphasised the need for more than one sampling occasion per period and an awareness of non-tobacco sources of smoke constituents under investigation. No consistent dose response, in line with ISO tar yield smoked, of MLE estimates was found for nicotine, pyrene and acrolein and respective biomarkers. The influence of demographics on our results has also been examined.
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Regul. Toxicol. Pharmacol. · Dec 2011
Comparative Study Controlled Clinical TrialA study to evaluate the effect on Mouth Level Exposure and biomarkers of exposure estimates of cigarette smoke exposure following a forced switch to a lower ISO tar yield cigarette.
A forced switch to a lower ISO tar yield cigarette was used in a clinical study, conducted in Germany, that compared two methods of estimating exposure to cigarette smoke. Pre- and post-switch estimates of Mouth Level Exposure (MLE) to nicotine, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), pyrene and acrolein were obtained by chemical analysis of spent cigarette filters for nicotine content. Similarly, pre- and post-switch estimates of uptake of these smoke constituents were achieved by analysis of corresponding urinary biomarkers of exposure (BoE): total nicotine equivalents; total 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL); total 1-hydroxypyrene (1-OHP), and 3-hydroxypropyl-mercapturic acid (3-HPMA), plus the nicotine metabolite cotinine, in plasma and saliva. ⋯ Changes in daily exposure estimates were determined on a group and individual basis for both methods. The pre- to post-switch directional changes in MLEs and their corresponding BoEs were generally consistent and the MLE/BoE relationship maintained. Switching to a lower yield cigarette generally resulted in reductions in exposure with the resultant exposure level being similar to that seen in regular smokers of the lower yield cigarette.