Search

Significance: Characterisation of tobacco product emissions is an important step in assessing their impact on public health. Accurate and repeatable emissions data require that a leak-tight seal be made between the smoking or vaping machine and the mouth-end of the tobacco product being tested. This requirement is challenging because of the variety of tobacco product mouth-end geometries being puffed on by consumers today. We developed and tested a prototype universal smoking machine adaptor (USMA) that interfaces with existing machines and reliably seals with a variety of tobacco product masses and geometries., Methods: Emissions were machine-generated using the USMA and other available adaptors for a variety of electronic cigarettes (n=7 brands), cigars (n=4), cigarillos (n=2), a heated tobacco product, and a reference cigarette (1R6F), and mainstream total particulate matter (TPM) and nicotine were quantified. Data variability (precision, n≥10 replicates/brand) for all products and error (accuracy) from certified values (1R6F) were compared across adaptors., Results: TPM and nicotine emissions generated using the USMA were accurate, precise and agreed with certified values for the 1R6F reference cigarette. Replicate data indicate that USMA repeatability across all tobacco products tested generally meets or exceeds that from the comparison adaptors and extant data., Conclusion: The USMA seals well with a variety of combustible tobacco products, e-cigarettes with differing geometries and plastic-tipped cigarillos. Variability for all measures was similar or smaller for the USMA compared with other adaptors., Competing Interests: Competing interests: No, there are no competing interests., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

Significance: Historically, tobacco product emissions testing using smoking machines has largely focused on combustible products, such as cigarettes and cigars. However, the popularity of newer products, such as electronic cigarettes (e-cigarettes), has complicated emissions testing because the products' mouth-end geometries do not readily seal with existing smoking and vaping machines. The demand for emissions data on popularly used products has led to inefficient and non-standardised solutions, such as laboratories making their geometry-specific custom adaptors and/or employing flexible tubing, for each unique mouth-end geometry tested. A user-friendly, validated, universal smoking machine adaptor (USMA) is needed for testing the variety of tobacco products reflecting consumer use, including e-cigarettes, heated tobacco products, cigarettes, plastic-tipped cigarillos and cigars., Methods: A prototype USMA that is compatible with existing smoking/vaping machines was designed and fabricated. The quality of the seal between the USMA and different tobacco products, including e-cigarettes, cigars and cigarillos, was evaluated by examining the leak rate., Results: Unlike commercial, product-specific adaptors, the USMA seals well with a wide range of tobacco product mouth-end geometries and masses. This includes e-cigarettes with non-cylindrical mouth ends and cigarillos with cuboid-like plastic tips. USMA leak rates were lower than or equivalent to commercial, product-specific adaptors., Conclusion: This report provides initial evidence that the USMA seals reliably with a variety of tobacco product mouth-end geometries and can be used with existing linear smoking/vaping machines to potentially improve the precision, repeatability and reproducibility of machine smoke yield data. Accurate and reproducible emissions testing is critical for regulating tobacco products., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

Introduction: In response to reducing cigarette nicotine content, people who smoke could attempt to compensate by using more cigarettes or by puffing on individual cigarettes with greater intensity. Such behaviors may be especially likely under conditions where normal nicotine content (NNC) cigarettes are not readily accessible. The current within-subject, residential study investigated whether puffing intensity increased with very low nicotine content (VLNC) cigarette use, relative to NNC cigarette use, when no other nicotine products were available., Aims and Methods: Sixteen adults who smoke daily completed two four-night hotel stays in Charleston, South Carolina (United States) in 2018 during which only NNC or only VLNC cigarettes were accessible. We collected the filters from all smoked cigarettes and measured the deposited solanesol to estimate mouth-level nicotine delivery per cigarette. These estimates were averaged within and across participants, per each 24-h period. We then compared the ratio of participant-smoked VLNC and NNC cigarette mouth-level nicotine with the ratio yielded by cigarette smoking machines (when puffing intensity is constant)., Results: Average mouth-level nicotine estimates from cigarettes smoked during the hotel stays indicate participants puffed VLNC cigarettes with greater intensity than NNC cigarettes in each respective 24-h period. However, this effect diminished over time (p < .001). Specifically, VLNC puffing intensity was 40.0% (95% CI: 29.9, 53.0) greater than NNC puffing intensity in the first period, and 16.1% (95% CI: 6.9, 26.0) greater in the fourth period., Conclusion: Average puffing intensity per cigarette was elevated with exclusive VLNC cigarette use, but the extent of this effect declined across four days., Implications: In an environment where no other sources of nicotine are available, people who smoke daily may initially attempt to compensate for cigarette nicotine reduction by puffing on individual cigarettes with greater intensity. Ultimately, the compensatory behavior changes required to achieve usual nicotine intake from VLNC cigarettes are drastic and unrealistic. Accordingly, people are unlikely to sustain attempts to compensate for very low cigarette nicotine content., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Solanesol, a naturally occurring constituent of tobacco, has been utilized as a good marker for environmental tobacco smoke particulate and as a noninvasive predictor of mainstream cigarette smoke tar and nicotine intake under naturalistic smoking conditions. A fast and accurate method for measuring free solanesol to assess tobacco smoke exposure is highly desirable. We have developed and validated a new environmentally friendly, high-throughput method for measuring solanesol content in discarded cigarette filter butts. The solanesol deposited in the used filters can be correlated with mainstream smoke deliveries of nicotine and total particle matter to estimate constituent delivery to smokers. A portion of filter material is removed from cigarette butts after machine smoking, spiked with internal standard solution, extracted and quantitatively analyzed using reverse-phase liquid chromatography coupled to a triple-quadrupole mass spectrometer. The new method incorporates a 48-well plate format for automated sample preparation that reduces sample preparation time and solvent use and increases sample throughput 10-fold compared to our previous method. Accuracy and precision were evaluated by spiking known amounts of solanesol on both clean and smoked cigarette butts. Recoveries exceeded 93% at both low and high spiking levels. Linear solanesol calibration curves ranged from 1.9 to 367 µg/butt with a 0.05 µg/butt limit of detection., (© The Author(s) 2021. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Standard machine smoking protocols provide useful information for examining the impact of design parameters, such as filter ventilation, on mainstream smoke delivery. Unfortunately, their results do not accurately reflect human smoke exposure. Clinical research and topography devices in human studies yield insights into how products are used, but a clinical setting or smoking a cigarette attached to such a device may alter smoking behavior. To better understand smokers' use of filtered cigarette products in a more natural environment, we developed a low-cost, high-throughput approach to estimate mainstream cigarette smoke exposure on a per-cigarette basis. This approach uses an inexpensive flatbed scanner to scan smoked cigarette filter butts and custom software to analyze tar-staining patterns. Total luminosity, or optical staining density, of the scanned images provides quantitative information proportional to mainstream smoke-constituent deliveries on a cigarette-by-cigarette basis. Duplicate sample analysis using this new approach and our laboratory's gold-standard liquid chromatography/tandem mass spectrometry (LC/MS/MS) solanesol method yielded comparable results (+7% bias) from the analysis of 20 commercial cigarettes brands (menthol and nonmentholated). The brands varied in design parameters such as length, filter ventilation, and diameter. Plots correlating the luminosity to mainstream smoked-nicotine deliveries on a per-cigarette basis for these cigarette brands were linear (average R 2 > 0.91 for nicotine and R 2 > 0.83 for the tobacco-specific nitrosamine NNK), on a per-brand basis, with linearity ranging from 0.15 to 3.00 mg nicotine/cigarette. Analysis of spent cigarette filters allows exposures to be characterized on a per-cigarette basis or a "daily dose" via summing across results from all filter butts collected over a 24 h period. This scanner method has a 100-fold lower initial capital cost for equipment than the LC/MS/MS solanesol method and provides high-throughput results (~200 samples per day). Thus, this new method is useful for characterizing exposure related to filtered tobacco-product use.

Nitromethane is a volatile organic compound categorized as a Group 2B carcinogen by the International Agency for Research on Cancer. It has been detected in mainstream cigarette smoke, but few reliable methods have been reported for accurate quantification. We developed, a sensitive, selective, fully validated method for the targeted determination of nitromethane in mainstream tobacco smoke in ten U.S. domestic brands and two quality control materials (3R4F and CM6). The vapor phase portion of machine-generated cigarette mainstream smoke, under modified ISO 3308:2000 regime (ISO) and modified intense regime (HCI), from single cigarettes was collected using airtight polyvinylfluoride sampling bags. The bags' contents were extracted using methanol containing an isotopically labeled internal standard followed by gas chromatography-tandem mass spectrometry. This approach is sufficiently sensitive to measure nitromethane levels in the nanogram range, with a method limit of detection of 72.3 ng/cig. Within-product variability estimated from the replicate analysis of 10 products ranged from 4.6%-16.3% (n = 6) over the two different smoking regimes, and method reproducibility estimated from two products used as quality control materials (3R4F and CM6) yielded intermediate precision values ranging from 16.6 to 20.8% (n = 20). Under HCI, nitromethane yields in machine-generated cigarette smoke from ten different domestic cigarette products ranged from 3.2 to 12 μg/cig; under ISO yields ranged from 1.6 to 4.9 μg/cig under standardized smoking machine conditions. Nitromethane yields are related to both the smoke regime (blocking of vent holes, puff duration and puff volume) and the heterogeneity of tobacco mixtures. This method provides a selective and fully validated technique to accurately quantify nitromethane in mainstream cigarette smoke, with minimal waste generation. It is an improvement over previous methods with regards to specificity, throughput, and simplicity of the sample collection process., Competing Interests: The authors report no declarations of interest.

Background: A mandated reduction in the nicotine content of cigarettes could reduce smoking rate and prevalence. However, one concern is that smokers may compensate by increasing the intensity with which they smoke each cigarette to obtain more nicotine. This study assessed whether smokers engage in compensatory smoking by estimating the mouth-level nicotine intake of low nicotine cigarettes smoked during a clinical trial., Methods: Smokers were randomly assigned to receive cigarettes with one of five nicotine contents for 6 weeks. An additional group received a cigarette with the lowest nicotine content, but an increased tar yield. The obtained mouth-level nicotine intake from discarded cigarette butts for a subset of participants (51-70/group) was estimated using solanesol as described previously. A compensation index was calculated for each group to estimate the proportion of nicotine per cigarette recovered through changes in smoking intensity., Results: There was no significant increase in smoking intensity for any of the reduced nicotine cigarettes as measured by the compensation index (an estimated 0.4% of the nicotine lost was recovered in the lowest nicotine group; 95% confidence interval, -0.1 to 1.2). There was a significant decrease in smoking intensity for very low nicotine content cigarettes with increased tar yield., Conclusions: Reductions in nicotine content did not result in compensatory changes in how intensively participants smoked research cigarettes., Impact: Combined with data from clinical trials showing a reduction in cigarettes smoked per day, these data suggest that a reduction in nicotine content is unlikely to result in increased smoke exposure., (©2020 American Association for Cancer Research.)

Globally, smokeless tobacco (ST) includes a wide array of chemically diverse products generally used in the oral cavity. Although ST has been widely investigated, this study was undertaken to determine the levels of sugars (mono- and di-saccharides), alditols, and humectants present in major ST categories/subcategories by using high performance liquid chromatography coupled with a triple quadrupole mass spectrometer (HPLC-MS/MS). The products studied included chewing tobacco (loose leaf, plug, twist), US moist snuff, Swedish snus, creamy snuff, dry snuff, dissolvable tobacco products, and tobacco-coated toothpicks. The highest mean sugar level was detected in chewing tobacco (9.3-27.5%, w/w ), followed by dissolvable tobacco (2.1%); all other products were lower than 1%. Creamy snuff had the highest mean alditol levels (22.6%), followed by dissolvable tobacco (15.4%); all others had levels lower than 1%. The detected mean humectant levels ranged from non-detectable to 5.9%. This study demonstrates the broad chemical diversity among ST. This research may aid researchers and public health advocates investigating the exposures and risks of ST. [Beitr. Tabakforsch. Int. 28 (2019) 203-213].