Comparing the effects of electronic cigarette smoke and conventional cigarette smoke on lung cancer viability

Abstract

The popularity of electronic cigarettes (e-cigarettes) has been noted to be increasing in recent years — for multiple reasons, including the fact that e-cigarettes are often cheaper, available in a variety of “flavors,” and easily accessible, to both adolescents and young adults find e-cigarettes to be a more appealing option than traditional cigarettes. Even though levels of carcinogens are reduced in e-cigarettes in comparison with tobacco cigarettes, there is increasing concern that vaping e-cigarettes may also increase the risk of lung cancer. Instead of burning tobacco, e-cigarettes contain liquid solutions of three main components: solvents, flavors, and, mainly, nicotine. We hypothesized that the chemicals from e-cigarettes and cigarette smoke might affect lung cancer cell viability. To test this hypothesis, we collected smoke extracts from different types of cigarettes: regular tobacco, cigar-like e-cigarette, and vape-type e-cigarette. By exposing A549 cells, human lung cancer cells, to the different types of smoke extracts, we wanted to see how cell viability would be affected. Among the three different cigarette extracts, vape-type e-cigarette smoke extract significantly increased the A549 cell viability. Since vape-type e-cigarettes contain the highest concentration of nicotine compared to the other types of cigarettes, we hypothesized that nicotine might be the cause of increased lung cancer viability. When different concentrations of nicotine were tested on the A549 cell line, the results showed that up to 2% nicotine concentration increased the A549 cell viability significantly, but more than 5% nicotine concentration induced cell death due to its high toxicity. In conclusion, contrary to conventional thought, e-cigarettes, or vapes, may be more dangerous than tobacco cigarettes in terms of lung cancer viability.