Nicotine Flux

Studies & Commentaries

2024: Influence of nicotine form and nicotine flux on puffing behavior and mouth-level exposure to nicotine from electronic nicotine delivery systems

• "This study examines the effect of nicotine form and flux on puffing parameters and mouth-level nicotine exposure."
• Talih S, Hanna E, Salman R, Salam S, El-Hage R, Karaoghlanian N, Talih F, Baldassari S, Saliba N, Elbejjani M, Eissenberg T, El-Hellani A, Shihadeh A. Influence of nicotine form and nicotine flux on puffing behavior and mouth-level exposure to nicotine from electronic nicotine delivery systems. Drug Alcohol Depend. 2024 Jan 1;254:111052. doi: 10.1016/j.drugalcdep.2023.111052. Epub 2023 Dec 2. PMID: 38103538; PMCID: PMC10872307.

2023: GFN Fives Video: The Applicability of 'Nicotine Flux' in Tobacco Products Regulation

• Carrie Wade, PhD

2023: New Nicotine Alliance UI: FCTC COP10

• "Nicotine flux is the rate of vapour emissions from e-cigarettes. Regulating on this basis would limit everything from battery size to nicotine levels and nicotine forms. This would make all products effectively the same. It could also entail restricting puff duration or applying a minimum interpuff interval. The subject is discussed in the TobReg8 report..."

2023: Nicotine flux as a powerful tool for regulating nicotine delivery from e-cigarettes: Protocol of two complimentary randomized crossover clinical trials

• "Electronic cigarette (EC) use has increased rapidly in the last decade, especially among youth. Regulating nicotine delivery from ECs could help curb youth uptake and leverage EC use in harm reduction yet is complicated by varying device and liquid variables that affect nicotine delivery. Nicotine flux, the nicotine emission rate, is a parameter that incorporates these variables and focuses on the performance rather than the design of an EC. Nicotine flux therefore could be a powerful regulatory tool if it is shown empirically to predict nicotine delivery and subjective effects related to dependence."
• Citation: El-Hellani A, Hanna E, Sharma M, Blohowiak R, Joseph P, Eid T, Nadim H, El-Hage R, Salman R, Karaoghlanian N, Adeniji A, Salam S, Talih F, Elbejjani M, Breland A, Eissenberg T, Shihadeh A, Baldassarri SR, Talih S. Nicotine flux as a powerful tool for regulating nicotine delivery from e-cigarettes: Protocol of two complimentary randomized crossover clinical trials. PLoS One. 2023 Sep 21;18(9):e0291786. doi: 10.1371/journal.pone.0291786. PMID: 37733666; PMCID: PMC10513228.

2023: Comparison of nicotine emissions rate, ‘nicotine flux’, from heated, electronic and combustible tobacco products: data, trends and recommendations for regulation

• "We found that nicotine flux varied widely across tobacco products, from less than 0.1 µg/s to more than 100 µg/s, and that since 2015 the upper limit of the ENDS nicotine flux range has risen significantly and is now approaching that of combustible cigarettes. We also found that products that differ in nicotine flux may exhibit similar nicotine yields due to differences in user puffing behavior. Nicotine flux is a tool that can be used to regulate nicotine emissions of tobacco products, including ENDS."
• Citation: El Hourani M, Shihadeh A, Talih S CSTP Nicotine Flux Work Group, et alComparison of nicotine emissions rate, ‘nicotine flux’, from heated, electronic and combustible tobacco products: data, trends and recommendations for regulationTobacco Control 2023;32:e180-e183.

2023: Electronic Cigarette Nicotine Flux, Nicotine Yield, and Particulate Matter Emissions: Impact of Device and Liquid Heterogeneity

• ECIG device and liquid heterogeneity influence nicotine and other toxicant emissions. Better measurement of ECIG device and liquid characteristics is needed to understand nicotine and toxicant emissions and to inform regulatory policy.
• Citation: Soule EK, Mayne S, Snipes W, Do EK, Theall T, Höchsmann C, Talih S, Martin CK, Eissenberg T, Fuemmeler BF. Electronic Cigarette Nicotine Flux, Nicotine Yield, and Particulate Matter Emissions: Impact of Device and Liquid Heterogeneity. Nicotine Tob Res. 2023 Feb 9;25(3):412-420. doi: 10.1093/ntr/ntac196. PMID: 35965260; PMCID: PMC9910146.

2022: E-cigarette device and liquid characteristics and E-cigarette dependence: A pilot study of pod-based and disposable E-cigarette users

• We hypothesize that nicotine flux would be associated with the e-cigarette dependence scale (EDS) among pod-based and disposable e-cigarette products.
• Citation: Do EK, O'Connor K, Perks SN, Soule EK, Eissenberg T, Amato MS, Graham AL, Martin CK, Höchsmann C, Fuemmeler BF. E-cigarette device and liquid characteristics and E-cigarette dependence: A pilot study of pod-based and disposable E-cigarette users. Addict Behav. 2022 Jan;124:107117. doi: 10.1016/j.addbeh.2021.107117. Epub 2021 Sep 13. PMID: 34555560; PMCID: PMC8511126.

2021: “Open-System” Electronic Cigarettes Cannot be Regulated Effectively

• "There are at least three advantages to nicotine flux as a regulatory target. First, rate of drug delivery is a key aspect of the extent to which a drug will be abused, and nicotine flux describes the rate at which an ECIG delivers nicotine to the user. If the goal of regulation is to decrease the likelihood that ECIGs will be abused by a population (i.e., non-smoking youth), decreasing ECIG nicotine flux may be an effective way to achieve this goal. Second, a given ECIG’s nicotine flux is a result of all aspects of that ECIG’s characteristics (e.g., construction, wattage, liquid nicotine content) so regulators need not try to focus simultaneously on myriad targets that can evolve over time. Rather, they focus on a product performance target – a range of nicotine emission rates – and manufacturers can choose whatever device/liquid characteristics that they can prove fall within that target performance range safely. Note that the flux target need not be a single value, but rather a range of allowable nicotine flux conditions (i.e., a nicotine emission rate no less than X and no greater than Y), thus allowing for a range of closed system products. Third, a mathematical model can be used to predict the nicotine flux of any ECIG. Thus, regulators have at their disposal a tool that allows them to examine efficiently an array of products to determine if those products meet or fall outside of a specified nicotine flux range. Overall, a performance standard like nicotine flux has clear advantages over multiple product standards. However, as with restricting flavor availability and limiting nicotine content, flux regulation, whatever its advantages, fails in an open-system context where users are able to modify devices and liquids easily."
• Citation: Eissenberg T, Soule E, Shihadeh A; CSTP Nicotine Flux Work Group. 'Open-System' electronic cigarettes cannot be regulated effectively. Tob Control. 2021 Mar;30(2):234-235. doi: 10.1136/tobaccocontrol-2019-055499. Epub 2020 Mar 17. PMID: 32184338; PMCID: PMC7848783.

2019: What is the nicotine delivery profile of electronic cigarettes?

• "A potential first step in effective regulation may involve regulating the rate at which nicotine is emitted from an e-cigarette (i.e., nicotine “flux”; [98,99]). Using nicotine flux as a regulatory target, all of the factors that influence it (e.g., device power, liquid nicotine concentration, user behavior) can be accounted for, and conditions that produce a flux that is too low (i.e., ineffective nicotine delivery) or too high (e.g., exceeding the flux of a combustible cigarette) can be made unavailable to consumers. Whether or not nicotine flux is the correct regulatory target, the current state of affairs, in which uninformed consumers use products that may or may not deliver nicotine and a variety of other toxicants, is incompatible with an empirically-based regulatory approach that prioritizes public health."
• Citation: Voos N, Goniewicz ML, Eissenberg T. What is the nicotine delivery profile of electronic cigarettes? Expert Opin Drug Deliv. 2019 Nov;16(11):1193-1203. doi: 10.1080/17425247.2019.1665647. Epub 2019 Sep 13. PMID: 31495244; PMCID: PMC6814574.

2017: Transport phenomena governing nicotine emissions from electronic cigarettes: model formulation and experimental investigation

• "Performance standards are commonly written in consumer product regulations in the USA and elsewhere, and with the appropriate scientific basis, can be developed for ECIGs. To the extent that proposed performance standards will involve nicotine emissions, models like the one described can be used to predict nicotine emissions of any existing or future ECIG product, without recourse to costly testing in an analytical laboratory. These models can also be used to test the effects of proposed regulation on factors that influence nicotine flux."
• Citation: Talih S, Balhas Z, Salman R, El-Hage R, Karaoghlanian N, El-Hellani A, Baassiri M, Jaroudi E, Eissenberg T, Saliba N, Shihadeh A. Transport phenomena governing nicotine emissions from electronic cigarettes: model formulation and experimental investigation. Aerosol Sci Technol. 2017;51(1):1-11. doi: 10.1080/02786826.2016.1257853. Epub 2016 Nov 8. PMID: 28706340; PMCID: PMC5502764.

2015: Electronic Cigarette Effectiveness and Abuse Liability: Predicting and Regulating Nicotine Flux

• "In this commentary, we propose a conceptual framework intended to provide a convenient approach for evaluating and regulating the nicotine emitted from ECIGs. This framework employs nicotine flux to account for the total dose and rate at which nicotine reaches the user, 2 key factors in drug abuse liability. The nicotine flux is the nicotine emitted per puff second (e.g., mg/s) by a given ECIG design under given use conditions, and it can be predicted accurately using physical principles. We speculate that if the flux is too low, users likely will abandon the device and maintain conventional tobacco product use. Also, we speculate that if the flux is too high, individuals may suffer toxic side effects and/or the device may have higher-than-necessary abuse liability. By considering ECIG design, operation conditions, liquid composition, and puff behavior variables in combination, we illustrate how ECIG specifications can be realistically mandated to result in a target flux range."
• Citation: Shihadeh A, Eissenberg T. Electronic cigarette effectiveness and abuse liability: predicting and regulating nicotine flux. Nicotine Tob Res. 2015 Feb;17(2):158-62. doi: 10.1093/ntr/ntu175. Epub 2014 Sep 1. PMID: 25180079; PMCID: PMC4837999.

Comment: Risks of attempting to regulate nicotine flux in electronic cigarettes

• "Based on the evidence presented above, and with current technological evolution, it is our opinion that regulating nicotine flux in ECs, in terms of restricting usage patterns (e.g., restrict puff duration or apply a minimum interpuff interval), is unnecessary. It carries the potential risk of reducing ECs’ efficacy as smoking substitutes, while it provides no benefit in terms of safety."
• Citation: Farsalinos KE, Voudris V, Le Houezec J. Risks of attempting to regulate nicotine flux in electronic cigarettes. Nicotine Tob Res. 2015 Feb;17(2):163-4. doi: 10.1093/ntr/ntu207. Epub 2014 Oct 19. PMID: 25332460; PMCID: PMC4892707.

Response: Nicotine Flux: A Potentially Important Tool For Regulating Electronic Cigarettes

• Citation: Eissenberg T, Shihadeh A. Nicotine flux: a potentially important tool for regulating electronic cigarettes. Nicotine Tob Res. 2015 Feb;17(2):165-7. doi: 10.1093/ntr/ntu208. Epub 2014 Oct 19. PMID: 25332456; PMCID: PMC4838002.

Waiting on results

2023: The Vaping and Patterns of e-Cigarette Use Research Study: Protocol for a Web-Based Cohort Study

• Analytical Laboratory: Toxicity Testing