Are so-called e-cigarettes effective quit aids for tobacco smokers or a teen gateway product to real smoking? What is their nicotine content, and do they contain carcinogens or other toxins. Are they being marketed to youth?
Prompted by her own experience in taking a patient’s history and realizing there were no screening questions specific to e-cigarettes, Johns Hopkins pediatric resident Iris Leviner reviewed the literature for some answers.
“Our patients are asking about these products and using them, so it’s important for us to understand the evidence about them,” Leviner said at a recent Hopkins Children’s Center Grand Rounds.
Unfortunately, Leviner said, little research has been conducted on the devices, comprised of a plastic tube and a battery-powered electronic heating device that vaporizes a liquid nicotine cartridge. Also, while e-cigarettes have been marketed as devices that deliver nicotine safely and free of toxins, Leviner noted that little toxicity testing has been performed. Primary components of the nicotine solution and vapor content, she explained, include propylene glycol, glycerin, and nicotine, and trace amounts of N-nitrosamines, diethylene glycol, polycyclic aromatic hydrocarbons, anabasine, myosmine, and nicotyrine. Some of these compounds are carcinogenic, a warning generally not mentioned by marketers.
“We do know these devices contain less carcinogens and toxins than regular cigarettes, but some companies are claiming no side effects at all,” said Leviner.
Another problem is little or no regulation or quality control, added Leviner, noting that the Food and Drug Administration is mulling over whether to regulate e-cigarettes as standard tobacco products. Until it does, companies are not bound by the same marketing and manufacturing regulations of cigarette makers.
“There’s no quality control in production and between brands,” Leviner said. “Different brands have different compounds in them, and the research is only on some brands.”
Are there any connections between e-cigarettes and specific health conditions? Leviner cited a case study tying lipoid pneumonia—a rare, chronic inflammatory reaction to the presence of inhaled or aspirated lipid substances in the lungs—to recurrent exposure to glycerin-based oils found in e-cigarette nicotine vapor (Chest 2012;141(4):1110-1113). The researchers concluded that the case highlights harm caused by the nicotine-solution carrier and the delivery system of the e-cigarette. “However,” said Leviner, “this is a case study and not really a proven association with electronic cigarette use.”
How effective are e-cigarettes as quit aids? One study that monitored modifications in the smoking habits of 40 regular smokers—those unwilling to quit—found that the use of e-cigarettes substantially decreased cigarette consumption without causing significant side effects (BMC Public Health 2011;1:786). Another study found that the e-cigarettes alleviated the desire to smoke after overnight abstinence, were well tolerated and had a pharmacokinetic profile more like the Nicorette inhalator than a tobacco cigarette (Tobacco Control 2010 Apr;19(2):98-103). Yet another study of smokers 18 and older randomized to nicotine e-cigarettes, patches or placebo, found e-cigarettes modestly effective as a quit aid but not superior to other methods (Lancet 2013; 382: 629–37).
The marketing of electronic cigarettes to children and teens is another concern, said Leviner, noting that some e-cigarettes are colorfully packaged and contain vapor flavors like apple and cherry. The fact that some manufacturers disguise e-cigarettes as pens or USB ports for discrete use in public settings, even in school, is perceived as yet another attempt to appeal to younger users. Rather than a quit aid, some experts see e-cigarettes as a gateway product to tobacco smoking, leading to full-blown tobacco use and nicotine addiction.
Leviner concluded, “Electronic cigarette manufacturers are making unsubstantiated claims, the safety of e-cigarettes remain unknown, youth are vulnerable in an unregulated marketplace, and patients are asking about them, seeing them being used and using e-cigarettes themselves.”