Where there is vapor, there may be smoke, according to a new study that says young smokers who see someone using an e-cigarette experience an increase in desire to smoke a regular cigarette. The results of the study suggest that public e-cigarette use may have a detrimental effect on the cessation efforts in unwitting observers. This report, published in the May issue of the journal Tobacco Control, marks the latest shot fired in a volley of back-and-forth controversy between proponents and opponents of e-cigarettes.

Electronic or e-cigarettes deliver nicotine in an inhaled flavored vapor. The battery-powered devices heat and vaporize a flavored, nicotine-rich liquid. They do not involve any tobacco or combustion so many argue that they are much safer than conventional cigarettes. Whether or not they are beneficial for smoking cessation is hotly debated. E-cigarettes are currently not approved for marketing as a smoking cessation aid.

“There could be effects of being in the company of an e-cigarette user, particularly for young smokers,” study author Andrea King, professor of psychiatry and behavioral neuroscience at the University of Chicago, said in a statement provided by the university.

“For example, it’s possible that seeing e-cigarette use may promote more smoking behavior and less quitting,” she said.

King and colleagues studied 60 young adult smokers who conversed with an actor who used an e-cigarette or conventional cigarette during the interviews. The participants were then instructed to comment on their urge to smoke. The researchers found that the study participants reported that their urges to smoke after seeing the actor use an e-cigarette were nearly as high their urges to smoke after seeing the actor smoke a conventional cigarette.

“We know from past research that seeing regular cigarette use is a potent cue for someone to want to smoke,” King said. “We did not know if seeing e-cigarette use would produce the same effect [on smokers], but that is exactly what we found. When we retested participants 20 minutes after exposure, the desire to smoke remained elevated.”