Analysis of waterpipe aerosol constituents in accordance with the ISO standard 22486

Study of waterpipe smoking topography in Fars province of Iran

Despite a sharp increase in the use of the waterpipe (WP) has been noted recently in Iran, no information is available for the smoking behavior and topography parameters. The present study is intended to obtain the inhalation and smoking topography parameters for the Iranian WP smokers. The smoking data collected from 122 smoking sessions, including 192 WP smokers in the Iranian Fars province have been used to perform smoking topography assessments. The influence of demographic and smoking parameters on puffing data is obtained. Results have indicated that gender and tobacco type strongly affect puff volume and duration. Women smokers inhale smaller volume of smoke than men and puff duration is significantly increased for regular smokers than occasional smokers. However, the results of the present study have not revealed a major effect of age, residence and setting on the puffing behavior.

Key challenges for in vitro testing of tobacco products for regulatory applications: Recommendations for dosimetry

The Institute for In Vitro Sciences (IIVS) is sponsoring a series of workshops to develop recommendations for optimal scientific and technical approaches for conducting in vitro assays to assess potential toxicity within and across tobacco and various next-generation products (NGPs) including heated tobacco products (HTPs) and electronic nicotine delivery systems (ENDSs). This publication was developed by a working group of the workshop members in conjunction with the sixth workshop in that series entitled "Dosimetry for conducting in vitro evaluations" and focuses on aerosol dosimetry for aerosol exposure to combustible cigarettes, HTP, and ENDS aerosolized tobacco products and summarizes the key challenges as well as documenting areas for future research.

Indoor Exposure and Regional Inhaled Deposited Dose Rate during Smoking and Incense Stick Burning-The Jordanian Case as an Example for Eastern Mediterranean Conditions

Tobacco smoking and incense burning are commonly used in Jordanian microenvironments. While smoking in Jordan is prohibited inside closed spaces, incense burning remains uncontrolled. In this study, particle size distributions (diameter 0.01-25 µm) were measured and inhaled deposited dose rates were calculated during typical smoking and incense stick-burning scenarios inside a closed room, and the exposure was summarized in terms of number and mass concentrations of submicron (PN_Sub) and fine particles (PM_2.5). During cigarette smoking and incense stick-burning scenarios, the particle number concentrations exceeded 3 × 10⁵ cm^-3. They exceeded 5 × 10⁵ cm^-3 during shisha smoking. The emission rates were 1.9 × 10¹⁰, 6.8 × 10¹⁰, and 1.7 × 10¹⁰ particles/s, respectively, for incense, cigarettes, and shisha. That corresponded to about 7, 80, and 120 µg/s, respectively. Males received higher dose rates than females, with about 75% and 55% in the pulmonary/alveolar during walking and standing, respectively. The total dose rates were in the order of 10¹²-10¹³ #/h (10³-10⁴ µg/h), respectively, for PN_Sub and PM_2.5. The above reported concentrations, emissions rates, and dose rates are considered seriously high, recalling the fact that aerosols emitted during such scenarios consist of a vast range of toxicant compounds.

Investigating the transfer rate of waterpipe additives to smoke as an integral part of toxicological risk assessments

Waterpipe, also known as hookah, narghile or narghila, shisha or hubbly bubbly, is a tobacco-smoking device. Waterpipe tobacco is heated and consumed by a process of inhaling tobacco smoke, that bubbles through water before being inhaled. To date, limited studies have examined the transfer of waterpipe additives from tobacco to smoke. This study was designed to investigate the filtration ability of water in the waterpipe’s bowl to define exposure to additives in waterpipe smoke, which is an essential requirement to perform toxicological risk assessments of waterpipe additives. Within this study, a standard smoking protocol (ISO 22486) was used to evaluate the transfer of > 40 additives from experimental and commercially available samples. These results are the first to provide such an extensive dataset of information showing transfer rates varying between 6% and 61% depending on the additive. Various physicochemical parameters of the additives including water solubility, partition coefficient, molecular weight, boiling point, and vapor pressure were also evaluated to seek to identify any correlation to transfer rate that may be later used to predict transfer. The amount of additive transfer from waterpipe tobacco to the smoke was found to be moderately correlated to vapor pressure (Pearson correlation coefficient = 0.33) with subsequent multivariate analysis using step-wise selection indicating 39% of the transfer rate variance can be explained collectively by the additive boiling point, molecular weight, vapor pressure and water solubility. These findings underscore the complexity of additive transfer and highlight the necessity of exposure assessment for meaningful waterpipe additive risk assessments.

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Additive transfer evaluated using ISO 22486 plus charcoal to reflect consumer use

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First provision of extensive results showing varying transfer rates between 6–61%.

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39% of the transfer rate variance explained by four physiochemical properties.

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Findings underscore the complexity of additive transfer for waterpipe.

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Results show the necessity of exposure assessment for additive risk assessments.

Effects of flavourants and humectants on waterpipe tobacco puffing behaviour, biomarkers of exposure and subjective effects among adults with high versus low nicotine dependence

INTRODUCTION

Flavourants and humectants in waterpipe tobacco (WT) increase product appeal. Removal of these constituents, however, is associated with increased intensity of WT puffing, likely due to reduced nicotine delivery efficiency. To clarify the potential public health outcomes of restrictions on flavourants or humectants in WT, we evaluated the effects of these constituents on puffing behaviours, biomarkers of exposure and subjective effects among adults with high versus low WT dependence.

METHODS

N=39 high dependence and N=49 low dependence WT smokers (Lebanese Waterpipe Dependence Scale scores >10 = high dependence) completed four smoking sessions in a cross-over experiment. Conditions were preferred flavour with humectant (+F+H), preferred flavour without humectant (+F-H), unflavoured with humectant (-F+H) and unflavoured without humectant (-F-H). Measures of puff topography, plasma nicotine and expired carbon monoxide (eCO) boost, and subjective effects were assessed.

RESULTS

Level of WT dependence modified the effect of WT condition on average flow rate, average puff volume and eCO boost. Although, overall, participants puffed the +F+H WT least intensely and -F-H WT most intensely, this association was strongest among WT smokers with high dependence. Participants preferred smoking the +F+H WT and achieved the largest plasma nicotine boost in that condition.

DISCUSSION

Findings underscore the complexity of setting product standards related to flavourants and humectants in WT. Future research evaluating whether WT smokers with high dependence would quit or reduce their WT smoking in response to removal of flavourants or humectants from WT is necessary to appreciate the full public health effects of such policies.