The Effects of Changes in Cigarette Menthol Content on Acute Nicotine Pharmacology and Smoking Topography.

INTRODUCTION: Menthol influences the appeal and addictiveness of cigarette smoking, however the data regarding menthol's effects on nicotine pharmacokinetics (PK) and smoking topography are inconsistent. This study investigated the impact of different cigarette menthol levels on nicotine pharmacology and smoking topography in current menthol smokers. AIMS AND METHODS: The study was a double-blind, randomized, four-period, crossover study to investigate the effects of smoking cigarettes with varying menthol content (0, 3, 6, and 12 mg menthol) on nicotine PK, smoking topography, and subjective effects in current menthol smokers. Each experimental session consisted of a prescribed use session, followed by 145 min of no smoking and a 1-h ad libitum smoking session. Serial blood samples were collected; smoking topography was recorded using CReSS Lab topography device. RESULTS: There was no significant effect of menthol on nicotine PK after prescribed smoking of cigarettes with varying menthol contents. During ad libitum smoking, there was significantly smaller total puff volume and puff duration in the 12 mg menthol condition compared to other menthol conditions. Subjective and sensory measures indicated significantly higher overall positive ratings for the 3 mg and 6 mg menthol cigarettes compared to the 0 mg menthol cigarette; the 12 mg menthol cigarette was less liked and harsher than the 3 mg condition. CONCLUSIONS: These findings suggest that menthol, at concentrations reflecting the marketplace (3-6 mg), contributes to positive subjective smoking experiences among menthol smokers, but does not have a significant effect on nicotine PK or smoking topography in an acute laboratory setting. IMPLICATIONS: While our data indicate that varying menthol content does not have a significant impact on nicotine's pharmacological effects under acute exposure conditions, these data highlight the contribution of menthol's flavor and sensory effects to product preference and positive smoking experiences, which facilitate repeated experimentation, progression to regular use, and subsequent dependence.

A Method to Amend Cigarettes With Menthol for Use in Research.

INTRODUCTION: Studies have evaluated the role of menthol cigarettes on various addiction-related outcomes; however, the effect of varying menthol content on these outcomes has not been evaluated. We developed a method to amend non-menthol SPECTRUM Research Cigarettes to contain menthol at four different levels. AIMS AND METHODS: SPECTRUM Research Cigarettes, NRC 600 (0.8 mg nicotine; 10 mg tar), were modified to contain target menthol amounts at 3, 6, and 12 mg/cigarette by injecting 25 µL ethanol/triacetin/menthol solutions of varying concentrations (120 mg menthol/mL, 240 mg/mL, and 480 mg/mL) into four distinct locations in the filter and tobacco rod. Menthol content was tested in triplicate in the whole cigarette and in the tobacco rod and filter at 1, 24, 48, and 72 hours for each target menthol level using an extraction solution of quinoline in methyl-tert-butyl ether and measured using gas chromatography with flame ionization detection. RESULTS: Injections into the filter and tobacco rod (12.5 µL each) yielded equal menthol distribution up to 72 hours. However, total menthol content decreased from an average of 90.3% of the target menthol concentration at 1 hour to 80.7% at 72 hours in cigarettes stored individually in glass tubes at room temperature. Analysis of urinary menthol glucuronide confirmed that amended cigarettes used within 24 hours of injection delivered dose-related menthol levels to participants in a clinical laboratory setting. CONCLUSION: This method can be used to modify cigarettes with a range of reliable menthol levels in both filter and tobacco rod for use in laboratory and clinical research. IMPLICATIONS: This study presents a technique for modifying cigarettes with different levels of menthol that can reliably deliver dose-related menthol levels to participants when smoked in a clinical study. The technique can be used to quickly amend cigarettes to examine the independent effects of varying flavor and additive levels on smoking behavior, nicotine pharmacokinetics, mainstream smoke emissions, and other laboratory or clinical research outcomes.

A Comparison of Use Topography and Nicotine Pharmacokinetics Among Loose and Portioned Smokeless Tobacco Users.

INTRODUCTION: Moist snuff smokeless tobacco (ST) products are available in the United States in both "loose" and "portioned" (ie, pouched) formats, but no published study to date has clinically evaluated the associations between ST format, use behavior, and nicotine exposure. AIMS AND METHODS: Participants used their usual brand of ST (loose ST [n = 30] or portioned ST [n = 20]) during an experimental visit wherein use behavior and plasma nicotine pharmacokinetic parameters were measured following single use (first hour of the session) and ad libitum use (remaining 7 h of the session). Participants' ST products were chemically characterized prior to use for pH and nicotine content. RESULTS: The average amount per use (2.99 vs. 1.52 g; p = .005) and total amount used (11.45 vs. 5.4 g; p = .002) were significantly higher among the loose ST group. Maximum plasma nicotine concentration (Cmax; 33.4 vs. 19.1 ng/ml) and area under the nicotine concentration versus time curve (AUC) were significantly higher for the loose ST group for the first hour (1474.8 vs. 807.2 min* ng/ml; p = .003) and throughout the 8-hour session (15827.9 vs. 8155.3 min* ng/ml; p < .001). Significant associations were observed between free nicotine content and first use Cmax (rs = .488, loose ST group) and AUC0-1 h (rs = 0.448, loose ST group; rs = .441, portioned ST group). CONCLUSIONS: The loose ST group used more product and had a greater average deposition time per use than the portioned ST group. Nicotine exposure was more strongly associated with free nicotine content than total nicotine content. IMPLICATIONS: To our knowledge, the current investigation was the first study to date to clinically evaluate the associations between usual-brand smokeless format, use behavior, and nicotine exposure. We observed meaningful differences in use behavior and subsequent nicotine exposure between loose and portioned ST users. Further, we observed that nicotine exposure was more strongly associated with free nicotine content than total nicotine content.

Formulation of smokeless tobacco products with a wide range of pH to study nicotine pharmacokinetics and pharmacodynamics.

The rate of nicotine absorption from tobacco products is a determinant of addiction potential and other detrimental health effects. Oral nicotine bioavailability from moist snuff smokeless tobacco (ST) is influenced by nicotine content, pH, flavors, and tobacco cut. For use in a clinical study testing the effect of pH on nicotine pharmacokinetics, four investigational ST products that differed only in pH were produced. A commercial ST product (Copenhagen Long Cut Original, pH 7.7) was modified with citric acid monohydrate (23 mg/g tobacco) or sodium carbonate (4.6 and 11 mg/g) to create products with pH 5.0, 8.2, and 8.6, respectively. All products - including the original product with pH 7.7 - were individually packaged (approximately 2 g) in aluminum foil pouches and stored frozen (-20 °C); pH, nicotine, tobacco-specific nitrosamines, moisture content, and mold and yeast counts were tested for up to 19 months to verify stability. Remarkable stability was demonstrated in this packaging/storage combination. For example, pH from all products were within 0.1 pH units and never exceeded 0.2 units. Nicotine concentration averaged 9.07 mg/g at baseline, maximal deviations from baseline in the four products averaged 0.30 mg/g. Similarly, TSNA, moisture content, yeast, and mold did not materially change. This study illustrates a method of investigational tobacco products formulation by manipulating a single design feature (or component) with the purpose of independently and systematically assessing its influence on nicotine bioavailability in a clinical study.

A procedure to detect and identify specific chemicals of potential inhalation toxicity concern in aerosols.

OBJECTIVE: Understanding the potential inhalation toxicity of poorly characterized aerosols is challenging both because aerosols may contain numerous chemicals and because it is difficult to predict which chemicals may present significant inhalation toxicity concerns at the observed levels. We have developed a novel systematic procedure to address these challenges through non-targeted chemical analysis by two-dimensional gas chromatography-time-of-flight mass spectrometry (GC × GC-TOFMS) and assessment of the results using publicly available toxicity data to prioritize the tentatively identified detected chemicals according to potential inhalation toxicity. MATERIALS AND METHODS: The procedure involves non-targeted chemical analysis of aerosol samples utilizing GC × GC-TOFMS, which is selected because it is an effective technique for detecting chemicals in complex samples and assigning tentative identities according to the mass spectra. For data evaluation, existing toxicity data (e.g. from the U.S. Environmental Protection Agency CompTox Chemicals Dashboard) are used to calculate multiple toxicity metrics that can be compared among the tentatively identified chemicals. These metrics include hazard quotient, incremental lifetime cancer risk, and metrics analogous to hazard quotient that we designated as exposure-(toxicology endpoint) ratios. RESULTS AND DISCUSSION: We demonstrated the utility of our procedure by detecting, identifying, and prioritizing specific chemicals of potential inhalation toxicity concern in the mainstream smoke generated from the machine-smoking of marijuana blunts. CONCLUSION: By designing a systematic approach for detecting and identifying numerous chemicals in complex aerosol samples and prioritizing the chemicals in relation to different inhalation toxicology endpoints, we have developed an effective approach to elucidate the potential inhalation toxicity of aerosols.

Impact of smoked cannabis on tobacco cigarette smoking intensity and subjective effects: A placebo-controlled, double-blind, within-subjects human laboratory study.

Co-users of cannabis and tobacco frequently use cannabis, then tobacco cigarettes, in a sequential pattern within an occasion, that is, they "chase" smoked cannabis with a tobacco cigarette. The objective of this placebo-controlled, double-blind, within-subjects human laboratory study was to gather preliminary data on how smoking active versus placebo cannabis impacts tobacco cigarette smoking behavior, craving, and subjective effects. Adult daily cannabis and tobacco co-users (N = 9) were randomly assigned to two experimental visit orders (i.e., active cannabis (5.2% THC) first visit and placebo cannabis second visit, or vice versa). Participants smoked one cannabis cigarette, and approximately 30 min later were given a 5-min ad libitum period to smoke one of their own brand of tobacco cigarette. As expected, boost in plasma THC levels and cannabis-related subjective effects differed between active and placebo cannabis conditions. Tobacco cigarette puff topography measures and tobacco craving did not differ between cannabis conditions, but there appeared to be between-participants heterogeneity in cumulative total puff volume. After smoking active versus placebo cannabis, the changes in subjective effects of tobacco smoking after adjusting for pretobacco smoking levels were not significant. Results do not support the notion that immediate effects of smoked cannabis change the behavior of tobacco smoking. The strong overlap between cannabis and tobacco smoking may not be explained by primarily pharmacological factors, but may be driven by more nuanced and complex mechanisms involving pharmacological processes as well as learning factors. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

E-cigarettes and their impact on health: from pharmacology to clinical implications.

Worldwide, cigarette smoking is the major cause of premature mortality and diseases that can be prevented. Given that people continue smoking despite associated health risks, delivering nicotine without combustion should be considered a valuable and much less harmful way to reduce the public health burden caused by smoking. E­cigarettes could play such a role if they were proven to be less harmful than combustible cigarettes. Although the number of clinical trials and human studies assessing the safety of e­cigarettes is limited, numerous in vitro and in vivo studies reported on the potential harmful effects of the aerosol generated from e­cigarettes. This article reviews the results of major clinical trials and laboratory studies with regard to cancer as well as cardiovascular and respiratory risk associated with the use of e­cigarettes. Additionally, it also discusses the potential application of e­cigarettes as smoking cessation tools. Most studies have indicated so far that e­cigarettes are less harmful, but this applies only to smokers who completely switched to e­cigarettes. In the opinion of the authors, good-quality research is crucial to establish the tolerance, safety, efficacy, and harm reduction potential of new technologies. Considering a significant role that physicians and other health providers play in helping smokers, there is an urgent need for evidence­based guidelines and recommendations for clinical practitioners on potential benefits and risks of e­cigarette use.

Accuracy of Three Screening Tools for Prenatal Substance Use.

OBJECTIVE: To compare and evaluate the accuracy of three screening tools in identifying illicit drug use and prescription drug misuse among a diverse sample of pregnant women. METHODS: This prospective cross-sectional study enrolled a consecutive sample of 500 pregnant women, stratified by trimester, receiving care in two prenatal clinical settings in Baltimore, Maryland, from January 2017 to January 2018. All participants were administered three index tests: 4P's Plus, NIDA Quick Screen-ASSIST (Modified Alcohol, Smoking and Substance Involvement Screening Test), and the SURP-P (Substance Use Risk Profile-Pregnancy) scale, and administered reference tests (urine and hair drug testing) at the in-person baseline visit. To assess test-retest reliability of the index tests, screening tool administrations were repeated 1 week later by telephone. For each screening tool, sensitivity, specificity, positive predictive value, negative predictive value and test-retest reliability were computed. Results were stratified by age, race, and trimester of pregnancy. RESULTS: Of the 500 enrolled pregnant women, 494 completed the index screening tools, 497 completed reference testing, and 453 underwent test-retest analysis. For the 4P's Plus, sensitivity=90.2% (84.5, 93.8), and specificity=29.6% (24.4, 35.2). For the NIDA Quick Screen-ASSIST, sensitivity=79.7% (71.2, 84.2), and specificity=82.8% (78.1, 87.1). For the SURP-P, sensitivity=92.4% (87.6, 95.8) and specificity=21.8% (17.4, 27.2). Test-retest reliability (phi correlation coefficients) was 0.84, 0.77, and 0.79 for the 4P's Plus, NIDA Quick Screen-ASSIST and the SURP-P, respectively. For all screening tools, there were differences in validity indices by age and race, but no differences by trimester. CONCLUSION: The SURP-P and 4P's Plus had high sensitivity and negative predictive values, making them more ideal screening tests than the NIDA Quick Screen-ASSIST. A clear recommendation for a clinically useful screening tool for prenatal substance use is crucial to allow for prompt and appropriate follow-up and intervention.

Sweet flowers are slow, and weeds make haste: leveraging methodology from research on tobacco, alcohol, and opioid analgesics to make rapid and policy-relevant advances in cannabis science.

The legalization of medical and recreational cannabis use has occurred ahead of science. The current evidence base has poor utility for determining if cannabis products can meet the standards of safety, efficacy, and quality intrinsic to modern medicine, and for informing regulation of cannabis as a legal intoxicant. Individual jurisdictions that pass cannabis reforms may not have adequate resources to support the level of new scientific research needed to inform regulatory actions; this could make it difficult to keep a rapidly growing multi-billion-dollar cannabis industry in check. Further, the present lack of evidence-based regulatory oversight for cannabis parallels the climates that gave rise to the tobacco and prescription opioid epidemics, suggesting that continued omission may result in negative public health consequences. However, translating a methodological framework developed through research on these compounds may promote rapid advances in cannabis science germane to regulatory knowledge gaps. The present review highlights specific advancements in these areas, as well as in alcohol regulation, that are prime for informing policy-relevant cannabis science, and also offers some recommendations for evidence-based regulatory policy. Resulting progress may directly inform both regulation of cannabis in both medical and licit recreational drug frameworks, and new cannabis-related public health initiatives.

Systemic absorption of nicotine following acute secondhand exposure to electronic cigarette aerosol in a realistic social setting.

Evidence suggests exposure of nicotine-containing e-cigarette aerosol to nonusers leads to systemic absorption of nicotine. However, no studies have examined acute secondhand exposures that occur in public settings. Here, we measured the serum, saliva and urine of nonusers pre- and post-exposure to nicotine via e-cigarette aerosol. Secondarily, we recorded factors affecting the exposure. Six nonusers of nicotine-containing products were exposed to secondhand aerosol from ad libitum e-cigarette use by three e-cigarette users for 2 h during two separate sessions (disposables, tank-style). Pre-exposure (baseline) and post-exposure peak levels (Cmax) of cotinine were measured in nonusers' serum, saliva, and urine over a 6-hour follow-up, plus a saliva sample the following morning. We also measured solution consumption, nicotine concentration, and pH, along with use behavior. Baseline cotinine levels were higher than typical for the US population (median serum session one = 0.089 ng/ml; session two = 0.052 ng/ml). Systemic absorption of nicotine occurred in nonusers with baselines indicative of no/low tobacco exposure, but not in nonusers with elevated baselines. Median changes in cotinine for disposable exposure were 0.007 ng/ml serum, 0.033 ng/ml saliva, and 0.316 ng/mg creatinine in urine. For tank-style exposure they were 0.041 ng/ml serum, 0.060 ng/ml saliva, and 0.948 ng/mg creatinine in urine. Finally, we measured substantial differences in solution nicotine concentrations, pH, use behavior and consumption. Our data show that although exposures may vary considerably, nonusers can systemically absorb nicotine following acute exposure to secondhand e-cigarette aerosol. This can particularly affect sensitive subpopulations, such as children and women of reproductive age.

Slower nicotine metabolism among postmenopausal Polish smokers.

BACKGROUND: A non-invasive phenotypic indicator of the rate of nicotine metabolism is nicotine metabolite ratio (NMR) defined as a ratio of two major metabolites of nicotine - trans-3'-hydroxycotinine/cotinine. The rate of nicotine metabolism has important clinical implications for the likelihood of successful quitting with nicotine replacement therapy (NRT). We conducted a study to measure NMR among Polish smokers. METHODS: In a cross-sectional study of 180 daily cigarette smokers (42% men; average age 34.6±13.0), we collected spot urine samples and measured trans-3'-hydroxycotinine (3-HC) and cotinine levels with LC-MS/MS method. We calculated NMR (molar ratio) and analyzed variations in NMR among groups of smokers. RESULTS: In the whole study group, an average NMR was 4.8 (IQR 3.4-7.3). The group of women below 51 years had significantly greater NMR compared to the rest of the population (6.4; IQR 4.1-8.8 vs. 4.3; IQR 2.8-6.4). No differences were found among group ages of male smokers. CONCLUSIONS: This is a first study to describe variations in nicotine metabolism among Polish smokers. Our findings indicate that young women metabolize nicotine faster than the rest of population. This finding is consistent with the known effects of estrogen to induce CYP2A6 activity. Young women may require higher doses of NRT or non-nicotine medications for most effective smoking cessation treatment.

Cigarillo and Little Cigar Mainstream Smoke Constituents from Replicated Human Smoking.

Little cigar and cigarillo smoking is increasing in popularity in the U.S., but little is known about the topography and mainstream smoke (MSS) constituents of these types of cigar products. This report describes the quantity of selected MSS toxicants generated from puff-by-puff replication of human laboratory smoking. Participants were dual users of cigarettes and either little cigars ( n = 21) or cigarillos ( n = 23). In the laboratory smoking session, participants of the little cigar group smoked a filtered unflavored Winchester Little Cigar; those in the cigarillo group smoked an unfiltered, unflavored Black & Mild cigarillo. MSS components included both volatiles and semivolatile compounds. The MSS of five representative U.S. domestic cigarettes was generated using smoking topography profiles of the participants smoking their own brand of cigarettes. Machine smoking accurately replicated individual puff profiles as indicated by a high correlation between lab and machine smoked: time to smoke, number of puffs, and total puff volume. There was wide variability in smoking patterns across subjects of both little cigars and cigarillos. For example, total puff volume ranged from 84 to 732 mL after the little cigar and from 270 to 2089 mL after the cigarillo. Qualitatively, cigar smoke from little cigars and cigarillos were similar and resembles cigarette smoke. All analytes (VOC and SVOCs) were greater in cigarillo smoke compared to that of little cigars and cigarettes. However, when the toxicants were adjusted for grams of tobacco burned, little cigar smoke contained more nicotine, tobacco-specific nitrosamines, acetonitrile, and acrylonitrile compared with cigarillo smoke. When the constituents were adjusted for nicotine content, cigarillo MSS contained more of all toxicants compared with little cigar. Cigarillos and little cigars, like cigarettes, deliver nicotine and other toxicants known to be harmful to health; their regulation by the FDA is appropriate for their public health risk.

Comparison and validation of screening tools for substance use in pregnancy: a cross-sectional study conducted in Maryland prenatal clinics.

INTRODUCTION: Prescription-drug use in the USA has increased by more than 60% in the last three decades. Prevalence of prescription-drug use among pregnant women is currently estimated around 50%. Prevalence of illicit drug use in the USA is 14.6% among pregnant adolescents, 8.6% among pregnant young adults and 3.2% among pregnant adults. The first step in identifying problematic drug use during pregnancy is screening; however, no specific substance-use screener has been universally recommended for use with pregnant women to identify illicit or prescription-drug use. This study compares and validates three existing substance-use screeners for pregnancy-4 P's Plus, National Institute on Drug Abuse (NIDA) Quick Screen/Alcohol, Smoking, and Substance Involvement Screening Test (ASSIST) and the Substance Use Risk Profile-Pregnancy (SURP-P) scale. METHODS AND ANALYSIS: This is a cross-sectional study designed to evaluate the sensitivity, specificity and usability of existing substance-use screeners. Recruitment occurs at two obstetrics clinics in Baltimore, Maryland, USA. We are recruiting 500 participants to complete a demographic questionnaire, NIDA Quick Screen/ASSIST, 4 P's Plus and SURP-P (ordered randomly) during their regularly scheduled prenatal appointment, then again 1 week later by telephone. Participants consent to multidrug urine testing, hair drug testing and allowing access to prescription drug and birth outcome data from electronic medical records. For each screener, reliability and validity will be assessed. Test-retest reliability analysis will be conducted by examining the results of repeated screener administrations within 1 week of original screener administrations for consistency via correlation analysis. Furthermore, we will assess if there are differences in the validity of each screener by age, race and trimester. ETHICS AND DISSEMINATION: This study is approved by the Institutional Review Board of the University of Maryland (HP-00072042), Baltimore, and Battelle Memorial Institute (0619-100106433). All participants are required to give their informed consent prior to any study procedure.

A Pilot Randomized Controlled Trial of a Phone-based Intervention for Smoking Cessation and Relapse Prevention in the Postpartum Period.

OBJECTIVES: To pilot-test a Phone-based Postpartum Continuing Care (PPCC) protocol developed from existing evidence-based approaches to address both postpartum smoking relapse among low-income women who quit smoking during pregnancy and postpartum smoking increase among those who had cut down. METHODS: One hundred thirty low-income pregnant women who were current or recently quit tobacco smokers were recruited at their first prenatal appointment and randomized to either a Control (standard care) or Experimental (standard care + PPCC) group. An intent-to-treat analysis was conducted on biochemically verified data from 6 in-person interviews during pregnancy and postpartum. Feasibility with regard to recruitment, randomization, assessment, and implementation of PPCC were assessed, along with acceptability among the target population. RESULTS: PPCC was found to be feasible and acceptable to some participants, but not all. There were no significant differences in tobacco products per day at 6 months postpartum between groups; however, effect sizes differed at 6 weeks compared with 6 months postpartum. Similarly, there were no significant differences between groups in cessation rate (24% in each group) and past 90-day tobacco use (59 vs 55 days, for Control and Experimental groups, respectively). CONCLUSIONS: The PPCC intervention did not differentially reduce tobacco use postpartum compared with a controlled comparison group, though it was found to be acceptable among a subpopulation of low-income pregnant women and feasible with regard to recruitment, randomization, assessment procedures, and implementation. Further research is needed to identify an intervention that significantly improves smoking relapse rates postpartum.

Nicotine Content and Physical Properties of Large Cigars and Cigarillos in the United States.

Introduction: Cigars are combusted tobacco products consisting of filler, binder, and wrapper, which are derived from tobacco. Despite the abundance of literature on the composition of traditional combusted cigarettes, research is limited on the physical and chemical properties of cigars. Therefore, research on cigar properties may be useful to better understand their health impact. Methods: In this study, twenty large cigar and cigarillo products were characterized for physical properties (ie, weight, length, and diameter), filler nicotine content, and tobacco pH. Tobacco pH was used to calculate free nicotine content, free nicotine concentration, and percent free nicotine for all cigars using the Henderson-Hasselbach equation. An additional analysis was performed on a second batch of two large cigar and two cigarillo brands to determine within-brand consistency. All analyses were performed in triplicate. Results: The initial analysis of the twenty cigars showed that cigars exhibited wide variation in product size and nicotine content, although tobacco pH was similar across cigars. Furthermore, in the two large cigar and cigarillo brands analyzed a second time, there was considerable within-brand variance in nicotine content and concentration between the first and second analyses. Conclusions: While only a small sample of commercially-available cigars was analyzed, our data suggest there is wide variability in nicotine content and some physical properties in the domestic cigar market. The data may help to inform potential future regulatory decisions related to these products. Implications: This study reveals some of the challenges to experimental cigar research and illustrates the need to characterize cigar products (eg, nicotine and tobacco content) before use in clinical studies. Additional studies and characterization of the physical and chemical properties of cigars may be useful to further understand these products' toxicity, abuse potential, and public health impact.

Large Cigars: Smoking Topography and Toxicant Exposure.

Background: Cigar smoking in the United States continues despite decreases in cigarette smoking and increased tobacco control efforts. We compared large cigar and cigarette smoking for use patterns, smoking topography, and toxicant exposure. Methods: Dual users (n = 17, 94% men, 77% African American) smoked ad libitum either their usual cigarette brand or a study large cigar (Phillies Blunt) in two laboratory sessions. Plasma nicotine and exhaled carbon monoxide were collected before and after smoking. Smoking topography measures of puff volume, puff duration, puff velocity, and interpuff interval were also collected. Results: Both cigarettes and large cigars significantly increased plasma nicotine and carbon monoxide and significantly decreased the urge to smoke. Cigarettes delivered more nicotine per gram of tobacco smoked and per 1000 mL of puff volume. Number of puffs, time to smoke, puff volume, and puff velocity were significantly larger and interpuff interval was significantly shorter in large cigar smoking. The temporal pattern of puffing more intensely at the beginning of smoking was similar for both large cigars and cigarettes. Conclusions: People who regularly use both large cigars and cigarettes adapt their smoking pattern such that they are exposed to similar levels of nicotine from each product. The immediate increase in plasma nicotine and carbon monoxide suggest significant inhalation of large cigar smoke. These data call to question the assumption that cigar smoking is less toxic than cigarette smoking. By smoking large cigars, dual users expose themselves to toxic components that have been linked with the addiction risk, morbidity, and mortality of cigarette smoking. Implications: This study found that dual users of large cigars and cigarettes inhale significant quantities of carbon monoxide, nicotine, and presumably other components of mainstream smoke. Large cigar smoke exposure may lead to or sustain nicotine addiction as wells as subject large cigar consumers to similar risks associated with cigarette smoking such as lung cancer and cardiovascular disease.

Dual Use of Cigarettes, Little Cigars, Cigarillos, and Large Cigars: Smoking Topography and Toxicant Exposure.

OBJECTIVE: Smoking topography variables and toxicant exposure (plasma nicotine and exhaled CO) were examined in 3 groups of study participants that smoked both cigarettes and either filtered little cigars (Winchester), cigarillos (Black & Mild), or large cigars (Phillies Blunt). METHODS: Laboratory ad lib smoking of the cigar products was collected with a smoking puff analyzer; plasma levels of nicotine and exhaled CO were collected before and after smoking. RESULTS: Although there were no statistically significant differences in demographic and cigarette smoking topography among the groups, there were significant differences in how the different cigar products were smoked. Plasma nicotine boost was similar after all products but exhaled CO was greater after the cigarillo and large cigar than the little cigar. Some of the differences were due to the differences in article size but other differences were apparent even after adjustment for the amount of tobacco burned or the mouth intake (puff volume). CONCLUSIONS: The topography findings of differences among products challenge the practice of grouping cigars as a single entity in surveys, regulatory decisions, and discussions of toxicant exposure. The results add to the discussion of distinctions among products in the scientific assessment of public health risk and regulatory decisions.

Smoking Behavior and Smoke Constituents from Cigarillos and Little Cigars.

OBJECTIVE: Although most cigarillos and little cigars smokers also smoke cigarettes (dual use), there are few studies comparing toxicant exposure and smoking behavior in cigars and cigarettes. METHODS: Two groups of dual users smoked their usual brand of cigarette and either a Winchester unflavored little cigar (N = 21) or a Black & Mild cigarillo (N = 23). Acute exposure of nicotine and exhaled carbon monoxide (CO) and puffing topography parameters were collected. Individual cigar puffing data were used to machine-replicate smoking for analysis of volatile organic compounds (VOC) and semi-volatile organic compounds (SVOC) in mainstream smoke. RESULTS: There were significant differences in puff topography, plasma nicotine and exhaled CO after cigarettes, little cigars, and cigarillos. Puff topography differences between cigarillos and cigarettes were due to the difference in the size of the article. Mainstream cigar and cigarette smoke was qualitatively similar; the yield was dependent on the smoking behavior. When smoke yield was adjusted for weight of tobacco burned or puff volume, exposure differences decreased. CONCLUSIONS: There is a wide range of delivery of both SVOC and VOC components of cigar and cigarillo smoke. The difference in exposure is largely dependent on the article size and the amount consumed.

Measuring PM2.5, Ultrafine Particles, Nicotine Air and Wipe Samples Following the Use of Electronic Cigarettes.

BACKGROUND: Few studies have examined the extent of inhalation or dermal contact among bystanders following short-term, secondhand e-cigarette exposure. OBJECTIVE: Measure PM2.5 (particles < 2.5 microns), UF (ultrafine particles < 100 nm), and nicotine in air and deposited on surfaces and clothing pre-/during/post- a short-term (2-hour) e-cigarette exposure. METHODS: E-cigarettes were used ad libitum by three experienced users for 2 hours during two separate sessions (disposable e-cigarettes, then tank-style e-cigarettes, or "tanks") in a 1858 ft3 room. We recorded: uncorrected PM2.5 (using SidePak); UF (using P-Trak); air nicotine concentrations (using air samplers; SKC XAD-4 canisters); ambient air exchange rate (using an air capture hood). Wipe samples were taken by wiping 100 cm2 room surfaces pre- and post- both sessions, and clean cloth wipes were worn during the exposure and collected at the end. RESULTS: Uncorrected PM2.5 and UF were higher (p < .0001) during sessions than before or after. Median PM2.5 during exposure was higher using tanks (0.515 mg/m3) than disposables (0.035 mg/m3) (p < .0001). Median UF during exposure was higher using disposables (31 200 particles/cm3) than tanks (25 200 particles/cm3)(p < .0001). Median air nicotine levels were higher (p < .05) during both sessions (disposables = 0.697 ng/L, tanks = 1.833 ng/L) than before (disposables = 0.004 ng/L, tanks = 0.010 ng/L) or after (disposables = 0.115 ng/L, tanks = 0.147 ng/L). Median accumulation rates of nicotine on surface samples were 2.1 ng/100 cm2/h using disposables and 4.0 ng/100 cm2/h using tanks; for cloth samples, it was 44.4 ng/100 cm2/h using disposables and 69.6 ng/100 cm2/h using tanks (p < .01). Mean room ventilation rate was ~5 air changes per hour during both sessions. CONCLUSIONS: Short-term e-cigarette use can produce: elevated PM2.5; elevated UF; nicotine in the air; and accumulation of nicotine on surfaces and clothing. IMPLICATIONS: Short-term indoor e-cigarette use produced accumulation of nicotine on surfaces and clothing, which could lead to dermal exposure to nicotine. Short-term e-cigarette use produced elevated PM2.5 and ultrafine particles, which could lead to secondhand inhalation of these particles and any chemicals associated with them by bystanders. We measured significant differences in PM2.5 and ultrafine particles between disposable e-cigarettes and tank-style e-cigarettes, suggesting a difference in the exposure profiles of e-cigarette products.