Regulatory toxicology and pharmacology : RTP
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Regul. Toxicol. Pharmacol. · Jul 2013
TSNA levels in machine-generated mainstream cigarette smoke: 35 years of data.
This paper characterizes historical and current tobacco specific nitrosamine (TSNA) levels in mainstream (MS) cigarette smoke of US commercial cigarettes. To conduct this analysis, we gathered 35 years of published data of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and N-nitrosonornicotine (NNN) levels in MS cigarette smoke. We also assessed internal data of MS smoke NNK and NNN levels generated from various market monitoring initiatives and from control cigarettes used in a multi-year program for testing cigarette ingredients. ⋯ There was no indication that TSNA levels systematically increased in cigarette MS smoke over the 35-year analysis period. In particular, TSNA levels expressed as either per cigarette or normalized for tar suggest a downward trend in MS smoke over the past 10 years. The apparent downward trend in TSNA levels in MS smoke may reflect industry and agricultural community efforts to reduce levels of TSNAs in tobacco and cigarette smoke.
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Regul. Toxicol. Pharmacol. · Jun 2013
Review Meta Analysis Comparative StudyThe effect on health of switching from cigarettes to snus - a review.
Interest in snus (Swedish type moist snuff) as an alternative to smoking is increasing, but the evidence on the health effects of switching from cigarettes to snus has not previously been reviewed. We identified six epidemiological cohort or case-control studies, all from Sweden, which allowed comparison of cancer or cardiovascular disease risk in current snus users who formerly smoked ("switchers") with that of never snus users who continued to smoke ("continuers") or of never snus users who quit smoking ("quitters"). ⋯ Based on estimates from four studies for ischaemic/coronary heart disease or acute myocardial infarction, meta-analyses gave combined relative risk estimates of 0.55 (95% confidence interval 0.45-0.68) for switchers vs. continuers and 1.02 (95% confidence interval 0.83-1.26) for switchers vs. quitters. Though based on limited evidence with some weaknesses, these results are consistent with a recent review which found no increased risk of cancer or heart disease from snus use.
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Regul. Toxicol. Pharmacol. · Jun 2013
Randomized Controlled Trial Comparative StudyChanges in levels of biomarkers of exposure observed in a controlled study of smokers switched from conventional to reduced toxicant prototype cigarettes.
Reduced toxicant prototype (RTP) cigarettes with substantially reduced levels of tobacco smoke toxicants have been developed. Evaluation of these prototype cigarettes included measurement of biomarkers of exposure (BoE) to toxicants in smokers switched from conventional cigarettes to the RTPs. A 6-week single-blinded randomised controlled study with occasional clinical confinement was conducted (
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Regul. Toxicol. Pharmacol. · Nov 2012
Randomized Controlled TrialReduced exposure evaluation of an Electrically Heated Cigarette Smoking System. Part 3: Eight-day randomized clinical trial in the UK.
A randomized, controlled, open-label, parallel-group, single-center study to determine biomarkers of exposure to nine selected harmful and potentially harmful constituents (HPHC) in cigarette smoke and urinary excretion of mutagenic material in 160 male and female subjects smoking Marlboro cigarettes (6 mg tar, 0.5mg nicotine, and 7.0mg CO) at baseline. Subjects were randomized to continue smoking Marlboro cigarettes, or switch to using an Electrically Heated Cigarette Smoking System (EHCSS) smoking one of two EHCSS series-K cigarettes, the EHCSS-K6 cigarette (5mg tar, 0.3mg nicotine, and 0.6 mg CO) or the EHCSS-K3 cigarette (3mg tar, 0.2mg nicotine, and 0.6 mg CO), or switch to smoking Philip Morris One cigarettes (1mg tar, 0.1mg nicotine, and 2.0mg CO), or to no-smoking. The mean decreases from baseline to Day 8 were statistically significant (p ≤ 0.05) for all determined HPHC including benzene and CO (the primary objectives), and urinary excretion of mutagenic material in the EHCSS-K6 (range -35.5 ± 29.2% to -79.4 ± 14.6% [mean ± standard deviation]), EHCSS-K3 (range -41.2 ± 26.6% to -83.1 ± 9.2%), and PM1 (range -14.6 ± 24.1% to -39.4 ± 17.5%) groups. The largest reductions in exposure occurred in the no-smoking group (range -55.4 ± 45.0% to -100.0 ± 0.0%).
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Regul. Toxicol. Pharmacol. · Nov 2012
Randomized Controlled TrialReduced exposure evaluation of an Electrically Heated Cigarette Smoking System. Part 5: 8-Day randomized clinical trial in Japan.
A randomized, controlled, open-label, parallel-group, single-center study to determine biomarkers of exposure to twelve selected harmful and potentially harmful constituents (HPHCs) in cigarette smoke and urinary excretion of mutagenic material in 128 male and female Japanese subjects smoking Marlboro cigarettes (6 mg tar, 0.5mg nicotine, and 7.0mg CO) at baseline. Subjects were randomized to continue smoking Marlboro cigarettes, or switch to the Electrically Heated Cigarette Smoking System (EHCSS) and smoke either the EHCSS-K6 (5mg tar, 0.3mg nicotine, and 0.6 mg CO) or the EHCSS-K3 (3mg tar, 0.2mg nicotine, and 0.6 mg CO) cigarette, or switch to smoking Lark One cigarettes (1mg tar, 0.1mg nicotine, and 2.0mg CO), or to no-smoking. ⋯ Statistically significant reductions (all p ≤ 0.05) in exposure to ten cigarette smoke HPHC (range: -5.9% to -34.6%), but not urinary mutagenicity, were observed in the Lark One group. The largest mean reductions in exposure to HPHC (all p ≤ 0.01 level) occurred in the no-smoking group (range: -13.7% to -97.6%).