SRNT is the only international scientific society dedicated to fostering and disseminating research on tobacco and nicotine logo Society for the Study of Addiction
* see translation disclaimer below
Some key links

Some e-cigarettes do not contain nicotine, but most do, or are capable of delivering nicotine (this applies to products that have refillable containers for the liquid). Studies of product contents and vapor, and absorption of nicotine into the bloodstream indicate wide variability across products; and factors such as the experience of the user and puffing techniques employed also play an important role in nicotine delivery, such that some users can achieve similar levels of nicotine to those found in tobacco smokers.

E-cigarette aerosols have been found to have particle diameters of average mass in the 250-450 nm range and particle number concentrations in the 10 particles/cm3 range, comparable to those observed for tobacco cigarette smoke. These findings suggest the potential for e-cigarette vapor particles - with nicotine - to penetrate deep into the respiratory tract (Ingebrethsen et al., 2012; Zhang et al., 2013).

The first published studies of nicotine delivery by e-cigarettes found peak serum nicotine concentrations were highly variable and on average much lower and rose far more slowly than with tobacco cigarettes (Bullen et al., 2010; Eissenberg, 2010). In one of these studies the levels of nicotine found were comparable with those following use of the nicotine inhaler by the same participants (Bullen et al., 2010). However, these studies were conducted among e-cigarette naive users with early e-cigarette devices, so it is likely that the results reflected their inexperience with the devices and limitations of the devices.

Cotinine was found in the saliva of e-cigarette users at levels commensurate with that of tobacco smokers, providing indirect evidence effective nicotine delivery can occur with these devices (Etter & Bullen, 2012). Studies with newer devices show a mixed picture – in laboratory studies, experienced users puffing their own e-cigarettes were exposed to nicotine doses similar to those of a standard cigarette, suggesting that especially for e-cigarette-naive users, instruction and product standardization may be needed to optimize nicotine delivery (Vansickel et al., 2012; Vansickel & Eissenberg, 2013). Farsalinos et al. (2013) found nicotine delivery with a newer-generation atomizer and 9mg/ml e-liquid was half that of a tobacco cigarette (1mg nicotine) and almost 60% lower than a 4mg medical nicotine inhaler.

Significant variability exists between and within brands in the airflow rate required to produce aerosol, pressure drop, length that cartridges last and production of aerosol and nicotine content (Williams & Talbot, 2011). E-cigarette users show a large variation in puff duration (Hua et al., 2011). First generation/ ‘lookalike’ e-cigarettes reportedly require stronger suction to draw in vapor than newer generation e-cigarettes, and tobacco cigarettes; and there is variability in aerosol density as puffing continues, and variation within and between brands (Trtchounian et al., 2010).

In a recent study comparing the nicotine delivery by new e-cigarettes with first-generation devices, and with tobacco, Farsalinos et al (2014) found the new-generation devices were more efficient in nicotine delivery than first generation models, yet delivered nicotine far slower compared to tobacco cigarettes. (plasma nicotine levels were higher by 35–72% using the new- compared to the first-generation device and delivered one-third to one-fourth the amount of nicotine of tobacco cigarettes, after 5 minutes use. However, they used 18 mg/ml nicotine liquid, which may have been too low to approach the nicotine-delivery profile of tobacco cigarettes.

Farsalinos et al. (2013) found substantial differences between e-cigarette use topography and smoking topography and between experienced and novice users in their evaluation of one brand of e-cigarette. This should be considered when designing laboratory and clinical trials and in developing standards for evaluating performance.

Bullen C, McRobbie H, Thornley S, Glover M, Lin R, Laugesen M. Effect of an electronic nicotine delivery device (e cigarette) on desire to smoke and withdrawal, user preferences and nicotine delivery: randomised cross-over trial. Tob Control. 2010 Apr;19(2):98-103.

Eissenberg T. Electronic nicotine delivery devices: ineffective nicotine delivery and craving suppression after acute administration. Tob Control. 2010 Feb;19(1):87-8.

Etter JF, Bullen C. Saliva cotinine levels in users of electronic cigarettes. Eur Respir J. 2011 Nov;38(5):1219-20.

Farsalinos KE, Spyrou A, Tsimopoulou K, Stefopoulos C, Romagna G, Voudris V. Nicotine absorption from electronic cigarette use: comparison between first and new-generation devices. Sci Rep. 2014;4.

Farsalinos KE, Romagna G, Tsiapras D, Kyrzopoulos S, Voudris V. Evaluation of electronic cigarette use (vaping) topography and estimation of liquid consumption: implications for research protocol standards definition and for public health authorities' regulation. Int J Environ Res Public Health. 2013 Jun 18;10(6):2500-14.

Goniewicz ML, Hajek P, McRobbie H. Nicotine content of electronic cigarettes, its release in vapour and its consistency across batches: regulatory implications. Addiction 2014 Mar;109:500-7. doi: 10.1111/add.12410. Epub 2013 Dec 18.

Hua M, Yip H, Talbot P. Mining data on usage of electronic nicotine delivery systems (ENDS) from YouTube videos. Tob Control. 2013 Mar;22(2):103-6.

Ingebrethsen BJ, Cole SK, Alderman SL. Electronic cigarette aerosol particle size distribution measurements. Inhal Toxicol. 2012 Dec;24(14):976-84.

Trtchounian A, Williams M, Talbot P. Conventional and electronic cigarettes (e-cigarettes) have different smoking characteristics. Nicotine Tob Res. 2010 Sep;12(9):905-12.

Vansickel AR, Eissenberg T. Electronic cigarettes: effective nicotine delivery after acute administration. Nicotine Tob Res. 2013 Jan;15(1):267-70.

Vansickel AR, Weaver MF, Eissenberg T. Clinical laboratory assessment of the abuse liability of an electronic cigarette. Addiction. 2012 Aug;107(8):1493-500.

Williams M, Talbot P. Variability among electronic cigarettes in the pressure drop, airflow rate, and aerosol production. Nicotine Tob Res. 2011 Dec;13(12):1276-83.

Zhang Y, Sumner W, Chen DR. In vitro particle size distributions in electronic and conventional cigarette aerosols suggest comparable deposition patterns. Nicotine Tob Res. 2013 Feb;15(2):501-8. logo
Home | Sitemap