Study documents secondhand exposure to nicotine from electronic cigarettes

Electronic cigarettes (e-cigarettes) are consumer products designed to generate nicotine aerosol, or vapor, without the combustion of tobacco. When an e-cigarette user takes a puff, the nicotine solution is heated, and the vapor is taken into the lungs. Researchers examined e-cigarette vapor from three different brands of e-cigarettes using a smoking machine in controlled exposure conditions. They also compared secondhand smoke exposure of e-cigarette vapor and tobacco smoke generated by dual users.

Results showed that e-cigarettes emitted significant amounts of nicotine, but did not emit substantial amounts of carbon monoxide and toxic volatile organic compounds. The level of secondhand exposure to nicotine depended on the e-cigarette brand. Additionally, the emissions of nicotine from e-cigarettes were significantly lower than those of conventional tobacco cigarettes. The U.S. Surgeon General found that there is no safe level of secondhand tobacco smoke, but has not evaluated health risk from secondhand exposure to e-cigarette vapors.

"To our knowledge, this is one of the first studies to measure the air concentrations of nicotine and volatile organic compounds and compare the emissions from electronic and conventional tobacco cigarettes," said Dr. Goniewicz, a researcher and Assistant Professor of Oncology in RPCI's Department of Health Behavior. "Our data suggest that secondhand exposure to nicotine from e-cigarettes is on average 10 times less than from tobacco smoke. However, more research is needed to evaluate the health consequences of secondhand exposure to nicotine from e-cigarettes, especially among vulnerable populations including children, pregnant women and people with cardiovascular conditions."

Study observations also include: • This study focused on nicotine and a limited number of chemicals released from e-cigarettes. Future research should explore emissions and exposures to other toxins and compounds identified in e-cigarettes such as formaldehyde, acetaldehyde and acrolein. • Data also are needed to determine whether secondhand exposure to e-cigarette vapors results in reinforcement of nicotine addiction. • More research is needed to investigate whether the vapor from e-cigarettes is deposited on surfaces to form 'thirdhand' e-cigarette vapor.

"Questions remain regarding the health impact of e-cigarettes among smokers and nonsmokers. It remains unclear whether young people will see e-cigarette use as a social norm and if e-cigarettes will be used as sources of nicotine in places with smoking bans, thus circumventing tobacco-free laws," said Andrew Hyland, PhD, Chair of the Department of Health Behavior at RPCI. "This study and others can guide policymakers as decisions are made about the regulation of the nicotine delivery devices."