E-Cigarettes with cigarette-level nicotine reduce smoking and carcinogen exposure

Article written by Bruce Sylvester.

E-cigarettes delivering cigarette-like levels of nicotine can reduce smoking and exposure to the tobacco-specific carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol, also known as NNAL.

Researchers reported these findings on April 12, 2021 in The Lancet Respiratory Medicine.

“[We found] e-cigarettes with nicotine delivery like a combustible cigarette were effective in helping reduce smoking and exposure to a tobacco-related carcinogen,” said lead author Caroline Cobb, Ph.D, associate professor of psychology at the Virginia Commonwealth University in Richmond, Virginia. “But it doesn’t just happen by accident. It requires the smoker to be actively trying to reduce their smoking by replacing it with e-cigarette use.”

The study lasted for 24 weeks. The subjects used an e-cigarette device delivering either 0, 8 or 36 milligrams of nicotine per milliliter of liquid nicotine, or an e-cigarette-like tube delivering no nicotine or aerosol.

The investigators screened 684 individuals and enrolled and randomized 520. They reported that 188 (36%) of 520 subjects were lost to follow-up by week 24, and attrition did not differ by study group.

At weeks 0, 4, 12 and 24, urine samples were taken to test for the carcinogen NNAL.

At week 24, subjects who used e-cigarettes filled with the cigarette-like level nicotine achieved significantly lower levels of NNAL compared to baseline, and compared to levels of NNAL among non-e-cigarette subjects.

“Use of an ENDS with cigarette-like nicotine delivery can reduce exposure to a major pulmonary carcinogen, NNAL, even with concurrent smoking,” the authors concluded.

This study is significant for two reasons, Cobb said. “First, many e-cigarettes have poor nicotine delivery profiles, and our results suggest that those products may be less effective in helping smokers change their behavior and associated toxicant exposure.”

“Second, previous randomized controlled trials examining if e-cigarettes help smokers change their smoking behavior/toxicant exposure have used e-cigarettes with low or unknown nicotine delivery profiles. Our study highlights the importance of characterizing the e-cigarette nicotine delivery profile before conducting a randomized controlled trial,” she added.