Correction: Corrigendum: Nicotine absorption from electronic cigarette use: comparison between experienced consumers (vapers) and naïve users (smokers)

Abstract

Electronic cigarettes (ECs) are nicotine delivery devices that are proposed as tobacco harm reduction products to smokers. Nicotine delivery from ECs is potentially important in their efficacy as smoking substitutes. Herein, nicotine delivery from using a new-generation EC device (variable-wattage, set at 9 W) was evaluated, comparing experienced (vapers) with naïve users (smokers). Twenty-four vapers and 23 smokers participated to the study. They were asked to obtain 10 puffs in 5 minutes and then use the EC ad lib for 60 more minutes (total duration of use: 65 minutes). An 18 mg/mL nicotine-containing liquid was used. Blood samples were obtained at baseline, 5-minutes and every 15 minutes thereafter, while number of puffs and average puff duration were recorded. Although at baseline both groups had similar plasma nicotine levels, smokers consistently exhibited lower levels at all time-periods; at 5-minutes the levels were lower by 46%, while during the subsequent period they were lower by 43% (at 65-minutes) to 54% (at 20-minutes). Both groups took similar number of puffs, but smokers had average puff duration of 2.3 s compared to 3.5 s in vapers. Even in vapers, plasma nicotine levels at 5 minutes were lower than those observed after smoking 1 tobacco cigarette.

E-cigarettes: Impact of E-Liquid Components and Device Characteristics on Nicotine Exposure

“…Using an advanced generation device (EVIC, 9 Watts, 18mg/ml nicotine e-liquid), experienced e-cigarette users, relative to e-cigarette-naïve combustible cigarette smokers, achieved 46% higher plasma nicotine levels after 5 minutes (10 directed puffs; but still lower than an average combustible cigarette) and maintained this approximate margin of higher nicotine levels throughout a 60-min ad libitum session. During the ad libitum session, the experienced and naïve groups did not differ in the number of puffs they self-administered, but experienced users took longer puffs on average (3.5 vs. 2.3 seconds) and the change in plasma nicotine levels across the session was significantly positively correlated (r=0.37) with puff duration [ 204 , 205 ]. Furthermore, in two linked studies, cigarette smokers (=/>10/day) who were familiar with but not regular users of e-cigarettes (N=24) reached lower nicotine peaks following 5 minutes (10 puffs/ 30 second interpuff interval) from an e-cigarette (Cmax 2.5ng/mL) relative to a combustible cigarette (Cmax 13.4ng/mL); while in the related study, regular e-cigarette users who smoked cigarettes occasionally (1-5/week) achieved equivalent peak nicotine levels after a 5-minute ad libitum bout of e-cigarette (Cmax for modular system= 7.8ng/mL; for first-generation rechargeable= 4.7ng/mL) or combustible cigarette (Cmax 7.2ng/mL)[ 206 ].…”

Week Long Topography Study of Young Adults Using Electronic Cigarettes in Their Natural Environment

“…The emerging literature on ENDS topography also consists of highly varied studies that feature different limitations, such as use environment, measurement devices and monitoring duration, making comparisons across studies challenging. Of the studies listed in Table 1 , seven were conducted in the laboratory environment [ 21 ], [ 22 ], [ 20 ], [ 20 ], [ 23 ], [ 24 ], [ 25 ]and only one [ 26 ] was conducted in the natural environment. Lab environment studies are limited in their ability to monitor natural behavior and therefore the resulting puff topography characteristics and any exposure data derived from them may not accurately represent actual patterns of users [ 27 ].…”

“…In particular, device failure causing loss of data was reported in one study [ 28 ] and inaccurate puff counts, and maximum recordable puffs limit of 43 puffs was reported in another study [ 22 ]. The EVIC, an ENDS manufactured by Joyetech that records puff duration, was used in one study [ 23 ] to measure puff duration, but without the knowledge of puff flow rate or puff volume, puff topography cannot be fully characterized. Ideally results from topography studies should accurately represent puffing behaviors of users in their natural environment, so it is preferential to capture user’s behavior in the natural environment, but until recently lack of adequate technology limited the studies to the lab environment.…”

Effect of e-liquid flavor on electronic cigarette topography and consumption behavior in a 2-week natural environment switching study

“…The FDA recognizes that regulation must be informed in-part by scientific findings on use behavior, including topography and consumption behavior associated with specific products and product components [ 4 – 6 ]. While cigarette smoking behavior has been widely studied [ 7 – 17 ],emerging evidence suggests that topography and consumption behavior associated with ENDS use differs from cigarette smoking [ 18 – 20 ]. Meaningful risk assessment associated with ENDS use is hindered by the wide variation in types of ENDS and e-liquid flavors available.…”

“…Several studies provide ENDS use topography [ 18 , 31 – 35 ] based on laboratory environment measurements, but none address how e-liquid flavors influence user topography and consumption behavior. Differences between laboratory and natural environment topography and consumption have been demonstrated for cigarettes [ 36 ], suggesting that use behavior is best assessed in the naturalistic setting.…”