A study published in Proceedings of the National Academy of Sciences suggested that the nicotine in e-cigarettes seems to cause damage to DNA in ways that would increase the risk of certain cancers for e-cigarette users.
According to lead researcher Moon-Zhong Tang, professor of environmental medicine at New York University School of Medicine, the study showed that the vaporized nicotine not only damaged DNA but also its ability to repair itself.
The study is the first research to produce evidence that e-cigarettes could be carcinogenic. “It is certainly concerning, and certainly gives pause if one were to say e-cigarettes were safe and could be used by all people without consequences,” said Dr. Roy Herbst, chief of medical oncology at Yale Cancer Center and chair of the American Association for Cancer Research’s Tobacco and Cancer Subcommittee.
In fact, this is not the first study to expose the dangers of smoking these devices. Previous research has connected e-cigarettes to the life-threatening respiratory disease known as popcorn lung. Tang and his colleagues conducted the research using a laboratory, which they exposed to e-cigarette vapor containing nicotine and liquid solvents. The researchers also exposed mice to nicotine and liquid solvents separately.
While previous studies conducted on the safety of e-cigarettes have used e-liquids heated at high levels of electricity, which resulted in other dangerous chemicals such as diacetyl being exposed, Tang’s team used lower levels of electricity, at or below the voltage that most all e-cigarettes operate. In testing the nicotine-solvent combination, as well as the solvent alone, the researchers found that the nicotine alone, and not the solvent, produces the effects that caused damage to the DNA. The researchers conducted similar tests on cultured human lung and bladder cells and found the same effects. Not all animal research results in similar outcomes when tested in humans, so researchers cannot say for certain that a human trial would result in similar DNA damage. However, if further research does confirm Tang’s results, Herbst says that could mean that e-cigarettes may carry their own cancer risk. Tang and his team are currently conducting research on the long-term effects of exposure to the nicotine in e-cigarettes using similar methods. From his research, Tang could not say whether he found e-cigarettes to be more dangerous than traditional cigarettes. “We just cannot guess with the data we have,” Tang explained.