The use of e-cigarettes, aka vaping, has risen sharply over the past few years, and according to a study by the University of Michigan's Monitoring the Future research group, that's because many people think the health risks associated with vaping are minimal. But new data out of the National Academy of Sciences shows that people who smoke e-cigarettes may "have a higher risk than nonsmokers to develop lung and bladder cancer and heart diseases," according to the study's report, which was published in the journal Proceedings of the National Academy of Sciences.
A team of researchers, led by professor of environmental medicine Moon-shong Tang, studied the effects of the nicotine aerosol vaping produces on mice and human cells in a laboratory setting over a period of three months. The team found that the aerosolized nicotine "could be converted into chemicals that damage DNA in the heart, lungs and bladder, and dampen down the body’s genetic repair mechanisms," reported The Guardian.
According to the study's report, there are currently 18 million e-cigarette smokers in the U.S., and those 18 million include 16 percent of high school students. "Understanding the carcinogenicity of [e-cigarette smoking] is an urgent public health issue," researchers concluded.
In most cases, e-cigarettes' only potentially dangerous ingredient is nicotine. Tang's team asserted in the study's report that "unlike [traditional smoking], which contains nitrosamines and numerous carcinogenic chemicals resulted from burning, [e-cigarette smoking] contains nicotine and relatively harmless organic solvents." Another study referenced in Tang's team's study showed that people who vape had 97 percent less of a particular nicotine nitrosamine and lung carcinogen than folks who were on nicotine replacement therapy.
But the effect of that nicotine — which the American Lung Association warns is "unregulated," adding that no e-cigarettes have been evaluated by the FDA — is what Tang and his fellow researchers set out to study. Mice involved in the study were exposed to e-cigarette smoke three hours per day, five days a week, for three months, according to the study's report, and at the end of the study, DNA damage was evident in them that was not evident in control group mice who had not inhaled the e-cigarette smoke.
The results of this study are preliminary to longer-term experiments "to look at the development of tumours [sic] in mice exposed to vapour [sic] from e-cigarettes," but Tang told The Guardian that people shouldn't expect conclusive results soon. "The results may take years to come in because cancer is such a slow process," he said.
Some researchers dismissed the results Tang and his team have already gotten. Peter Hajek, director of the Tobacco Dependence Research Unit at Queen Mary University of London, told The Guardian the study is "one in a long line of false alarms which may be putting people off the switch from smoking to vaping which would undoubtedly be of great benefit to them."
He added, "This study shows nothing at all about the dangers of vaping. The best current estimate is that vaping poses, at worst, some 5 [percent] of risks of smoking."
Another expert, Jasmine Just from Cancer Research UK, told The Guardian, "Research like this is important, but this lab study only looked at the effects of e-cigarette smoke on cells and on mice, which means it’s not possible to draw any conclusions from this about how e-cigarettes might affect people in real life."
Whether future research will show the results of Tang's team's study extend to humans isn't certain. Tang told The Guardian that "the DNA changes [found in mice exposed to vaping smoke] were similar to those linked to secondhand smoke, but added that more work was needed to see whether vaping really [does] increase cancer rates."