The study - published March 5, 2018 inPediatrics - analyzed urine from a group of adolescents with an average age of 16.4 years. Sixty-seven used e-cigarettes only and 17 used both e-cigarettes and traditional tobacco cigarettes. They were compared with a control group of 20 non-smoking teens.
Levels of toxic organic compounds were up to three times higher on average in the e-cigarette users compared with the controls. In teenagers who used both e-cigarettes and tobacco cigarettes, levels of toxic compounds were up to three times higher than in e-cigarette users only.
"Teenagers need to be warned that the vapor produced by e-cigarettes is not harmless water vapor, but actually contains some of the same toxic chemicals found in smoke from traditional cigarettes," said lead authorMark L. Rubinstein, MD, a professor of pediatrics at UCSF. "Teenagers should be inhaling air, not products with toxins in them. E-cigarettes are marketed to adults who are trying to reduce or quit smoking as a safer alternative to cigarettes. While they may be beneficial to adults as a form of harm reduction, kids should not be using them at all."
E-Cigarette Vapor Slows Heart Race In Mice
Electronic nicotine delivery systems (ENDS) such as e-cigarettes, affect heart rhythm and cardiovascular function in mice, according to preliminary research presented last year at the American Heart Association's Scientific Sessions, a premier global exchange of the latest advances in cardiovascular science for researchers and clinicians.
In addition to nicotine, e-cigarette products usually contain propylene glycol (PG) and/or vegetable glycerin (VG). These substances are commonly used to limit moisture loss in skin lotions or as food additives, but the health effects of heating and inhaling these substances are unknown.
In this study, researchers examined the cardiovascular effects of e-cigarette aerosols relative to traditional cigarettes in mice and found:
- Exposure to ENDS aerosol or traditional cigarette smoke rapidly slowed the heart rate (bradycardia) in mice.
- Exposure to aerosol of 50:50 vegetable glycerin and propylene glycol prolonged the heart's electrical cycle.
- When heated, propylene glycol and/or vegetable glycerin generate aldehydes, acrolein, acetaldehyde, and formaldehyde, of which, only acrolein induced bradycardia in mice.
- Exposure to acrolein or PG:VG aerosol increased blood pressure in mice before the heart rate began to drop.
While further studies are needed to explore these effects in humans using ENDS, these findings suggest that exposure to ENDS aerosols may trigger cardiovascular effects and may increase the risks of developing irregular heart rhythm and overall cardiovascular disease.
Can E-Cigarettes Help Smokers Quit?
As e-cigarettes become more popular, fewer people are taking up smoking traditional cigarettes. But can e-cigarettes, an electronic nicotine delivery system, help people quit smoking altogether? That was the focus of a recent study led by a Hollings Cancer Center researcher.
The study found that smokers who are willing to use e-cigarettes tend to smoke less and have increased quit attempts, said Matthew Carpenter, Ph.D., a tobacco control and addiction expert at the cancer center at the Medical University of South Carolina (MUSC). "Combustible cigarettes are the most harmful form of nicotine delivery. Alternative delivery of nicotine, through e-cigarettes, could significantly reduce harm and the risks of cancer and other diseases to smokers," he said.
In the pilot study, funded by the National Institutes of Health, Carpenter evaluated e-cigarettes in terms of usage, product preference, changes in smoking behaviors and nicotine exposure. Sixty-eight smokers were evaluated: 46 were randomized to use e-cigarettes however they wished, and 22 were randomized to a control group.
Those in the e-cigarette group were given a device with either high or low doses of nicotine. Everyone was followed over a period of four months. The study was published inCancer Epidemiology, Biomarkers & Prevention and is one of the few randomized studies in the U.S. to examine the effects of e-cigarettes and quit attempts.
Results showed that when smokers were given e-cigarettes, without any accompanying instructions or requirements for use, uptake was strong, and many participants went on to purchase their own e-cigarettes. This suggests that e-cigarettes might give smokers a suitable alternative to combustible cigarettes. Those who used e-cigarettes smoked less and were more likely to quit smoking, as compared to those in the control group.
"The results are consistent with trials done outside the U.S.," Carpenter said. "Many people rated the e-cigarettes similar to their usual product, which further suggests that these products might promote switching. Anything that gets smokers off combustible cigarettes is a good thing."
Of the two e-cigarette models used in the study, the more powerful device, with a higher dose of nicotine, showed stronger outcomes. People using e-cigarettes throughout the study smoked an average of 37 percent fewer cigarettes, showing a positive effect when making the switch and potentially serving as a tool to help smokers quit.
Smoking is the leading cause of cancer and has a negative impact on the effectiveness of cancer treatments. People who quit smoking, regardless of their ages, have substantial gains in life expectancy compared with those who continue to smoke.
E-Cigs Not For Everyone
Carpenter cautions that while e-cigarettes may help people smoke less or even quit, they are not for everyone. "It is important to protect non-smokers, particularly adolescents and young adults, from starting any nicotine-containing product. This is something we need to really guard against."
E-cigarettes are sometimes seen as a gateway to conventional cigarettes, the most harmful form of nicotine delivery. Studies have shown that e-cigarettes offer significantly less exposure to harmful toxicants, as compared to traditional cigarettes. "We know e-cigarettes are safer than traditional cigarettes, but that doesn't mean e-cigarettes are completely safe," says Carpenter.
More than 1,500 varieties of e-cigarettes are now available, including different looks, high-tech power settings, and many flavors, which can make them more appealing. Newer devices can be customized in many ways that will draw in more smokers, but that means they also can entice kids.
"We've gotten very good at the public health messaging of conventional smoking and prevention efforts for adolescents, but now kids see a new technology-based product that is supposedly safer, flavored and isn't a cigarette, Carpenter added. All these things raise our alarm bells for adolescents, and, in fact, e-cigarettes are more popular than conventional cigarettes among youth."
E-cigarettes were only recently regulated by the Food and Drug Administration. Largely manufactured overseas, the quality control process varies. Without enough information to answer the long-term public health issues of e-cigarettes, researchers like Carpenter are aware of the importance of further studies on the latest tobacco trends. Combustible cigarettes have been around for many decades. E-cigarettes have not, and the science has a lot of questions left to answer.
There's A Catch
Frequent e-cigarette use does help smokers quit a finding thatGeorgetown Lombardi Comprehensive Cancer Centerresearchers say supports the use of e-cigarettes as a cessation aid for those trying to quit cigarette smoking. But, they note, an examination of a recent national survey uncovers important clues about whos successful at quitting and why.
The findings - published in Nicotine & Tobacco Research - examined a national survey of more than 24,500 current or recent former cigarette smokers, which is the largest sample of smokers studied to date. This study, along with a recent studypublished in the BMJ, provides some of the strongest evidence so far on the link between use of e-cigarettes and cessation, says the studys lead author David Levy, Ph.D., professor of oncology at Georgetown Lombardi.
However, there are important nuances in the data that impact a persons success in quitting cigarette smoking. Both cigarette quit attempts and quit success were directly related to the number of days of e-cigarette use, Levy explains. The odds of quit success increased by 10 percent with each additional day of e-cigarette use.
The data also shows that among those making at least one quit attempt, quit success was lower among individuals who had used e-cigarettes at some point in the past, but higher among those with at least five days of e-cigarettes use in the last month. The data is drawn from a special tobacco use survey that, since 1992-1993, has been taken every three to four years as part of a population survey conducted monthly by the U.S. Census Bureau. The latest tobacco use survey, taken from 2014-2015, was co-sponsored by the National Cancer Institute and the U.S. Food and Drug Administration.
This survey - the Tobacco Use Supplement to the Current Population Survey(TUS-CPS) - is designed to track long-term trends in tobacco use, cessation attempts and tobacco-related policies. All states are represented, and participants are interviewed either by telephone or in person.
Levy and his Georgetown Lombardi colleagues examined the relationship between frequencies of e-cigarette use, cigarette quit attempts, and cigarette abstinence. Because of the dates of the survey, it includes the more current types of e-cigarettes that are more effective at delivering nicotine.
"Our findings are consistent with randomized trials and those observational studies that measure frequency of e-cigarette use, Levy said. These results support the use of e-cigarettes - especially consistent use - as an effective smoking cessation aid. Since e-cigarettes are generally estimated to have a small proportion of the mortality risks of cigarettes, this represents an important life-saving intervention that doctors can recommend when other forms of treatment fail.