HealthDay News — Electronic cigarette use is associated with a decrease in tobacco smoke toxicant exposure in those who quit smoking, as well as in dual users, according to a study published in Cancer Prevention Research.

Hayden McRobbie, MB, ChB, PhD, from Queen Mary University of London, and colleagues examined exposure to carbon monoxide (CO), nicotine, and acrolein before and after 4 weeks of electronic cigarette use in 40 smokers.

Overall, 33 participants were using electronic cigarettes four weeks after quitting. Forty-eight percent of electronic cigarette users were abstinent from smoking during the previous week (electronic cigarette-only users) and 52% were dual users.

Significant reductions in CO were seen in both electronic cigarette-only users and dual users (−12 ppm [80% decrease] and −12 ppm [52% decrease], respectively). There was a decrease in cotinine levels, albeit to a lesser extent (electronic cigarette-only users: −184 ng/mg creatinine; 17% decrease; dual users: −976 ng/mg creatinine; 44% decrease).

At four weeks there were decreases in acrolein, based on measurement of S-(3-hydropxypropyl)mercapturic acid in urine, for both electronic cigarette-only users and dual users (−1,280 ng/mg creatinine [79 percent decrease] and −1,474 ng/mg creatinine [60% decrease], respectively). Electronic cigarette use significantly reduced exposure to CO and acrolein in dual users due to reduced smoke intake.

Electronic cigarette use may reduce harm even in smokers who continue to smoke, but long-term follow-up studies are needed to confirm this,” the researchers wrote.

Disclosures: Two authors disclosed financial ties to the pharmaceutical industry; one author disclosed ties to manufacturers of stop-smoking medications.


  1. McRobbie H et al. Cancer Prev Res; 8(9); 873–8.