A small clinical study of eight veteran e-cigarette users demonstrates that the products are capable of delivering nicotine doses that are similar to those of cigarettes. The study was conducted by Andrea Rae Vansickel and Thomas Eissenberg of Virginia Commonwealth University and was published in Nicotine and Tobacco Research (abstract here).
Vansickel and Eissenberg studied blood nicotine levels and heart rate among subjects who used e-cigarettes according to a standard protocol after 12 hours of abstinence. All subjects had quit smoking 11 months earlier and were veteran vapers. Seven of the study participants used devices that operated with higher voltage and larger battery capacity than products typically sold in convenience stores.
Blood nicotine levels increased from 2 nanograms per milliliter (ng/ml) at baseline, to 10 ng/ml within 5 minutes of the first puff, and to 16 ng/ml at the end of the ad lib period of use. These levels are similar to those produced with cigarette smoking.
Vansickel and Eissenberg report that “User experience and/or device characteristics likely influence e-cigarette nicotine delivery and other effects.” This is important, because Eissenberg previously reported that e-cigarettes did not deliver measurable nicotine (article available here). However, that study recruited 16 smokers who had no prior experience with e-cigarettes, and they were told to “puff normally.” It is well known that use of e-cigarettes involves a learning curve; the devices require more vigorous inhalation than combustible cigarettes. It therefore makes sense that naïve smokers didn’t achieve measurable nicotine levels. Still, e-cigarettes produced somewhat lower craving scores.
Vansickel and Eissenberg conclude: “One important potential benefit of e-cigarette regulation may be more consistent nicotine delivery, device performance, and cartridge and vapor content.”
While regulation could ensure that consumers get reliable e-cigarette devices and liquids with consistent nicotine levels and no contaminants, it is essential that regulation not introduce barriers to smokers’ access to these potentially life-saving products.