The majority of electronic cigarettes (e-cigarettes) function by heating a liquid, which contains tobacco derived nicotine, propylene glycol, vegetable glycerin, and flavorings. While propylene glycol and vegetable glycerin are not carcinogenic when ingested, researchers are unclear about the long-term health effects of inhaling them. During the process of inhalation, either a battery-powered atomizer is activated or manually switched on. Inside the atomizer, a heating coil heats liquid nicotine, causing it to become vapor, which is then inhaled. According to the World Health Organization report, “Electronic nicotine delivery systems,” the capacity of electronic nicotine delivery systems (ENDS) “to deliver nicotine to the user varies widely, ranging from very low to levels similar to that of cigarettes, depending on product characteristics, user puffing behavior, and nicotine solution concentration.”
Current Findings on E-Cigarette Use
Monitoring the Future 2014: The National Institute on Drug Abuse released in December 2014 “Monitoring the Future 2014,” an annual survey conducted by researchers at the University of Michigan of 8th, 10th, and 12th graders measuring attitudes towards and use of drugs, alcohol, and cigarettes. The survey population consisted of 41,551 students from 377 public and private schools. Over the past two decades (1994-2014), cigarette use has mainly decreased. In 2014, 13.6% of 12th graders reported past 30-day use of cigarettes, 7.2% of 10th graders, and 4.0% of 8th graders. When comparing cigarette and e-cigarette past 30-day use, researchers found that teens were more likely to use e-cigarettes than cigarettes with 8.7% of 8th graders, 16.2% of 10th graders, and 17.1% of 12th graders reporting e-cigarette use. An additional research finding was that only 14.2% of 12th graders saw e-cigarette use as harmful, which the researchers noted is “less than 5 students in the average class.” Prior Monitoring the Future surveys did not record data on e-cigarettes, providing no comparative data to assess change over time.
Tobacco use Among Middle and High School Students – United States, 2013: The CDC released in November 2014 “Tobacco use Among Middle and High School Students – United States, 2013,” detailing findings from the National Youth Tobacco Survey for 2013. The National Youth Tobacco Survey is a self-administered questionnaire completed by US middle (grades 6-8) and high school (grades 9-12) students that assesses ever and current use (1 or more days in the past 30 days) of tobacco products including e-cigarettes. In the 2013 survey, 187 schools participated from 250 selected with a sample of 18,406 students and a response rate of 67.8%. The survey found that 22.9% of high school students reported current use of a tobacco product. Among high school students, “4.5% reported using e-cigarettes within the last 30 days; and 1.1% of middle school students reported using e-cigarettes in the last 30 days.” In comparison with results from the 2012 National Youth Tobacco Study, e-cigarette use among high school students rose from 2.8% but remained the same for middle school students. The difference in the two findings from “Monitoring the Future 2014” and the National Youth Tobacco Survey might be explained by a methodological difference of reporting data from individual grades versus combining grades (6-8, 9-12).
Intentions to Smoke Cigarettes Among Never-Smoking U.S. Middle and High School Electronic Cigarette Users, National Youth Tobacco Survey, 2011-2013: In August 2014, the journal Nicotine & Tobacco Research published a study “Intentions to Smoke Cigarettes Among Never-Smoking U.S. Middle and High School Electronic Cigarette Users, National Youth Tobacco Survey, 2011-2013” examining e-cigarette use among middle and high school students who have never smoked cigarettes. The study used student-reported information collected in connection with the National Youth Tobacco Survey from 2011-2013. Researchers explored data from students enrolled in grades 6-12 in both public and private schools. The researchers from the CDC, FDA, and Georgia State University found that from 2011-2013 the number of students who had “never smoked a cigarette but had used e-cigarettes at least once increased three-fold” from 79,000 in 2011 to over 263,000 in 2013. Additionally the study reported that students who had never smoked but had used e-cigarettes “were nearly twice as likely to have an intention to smoke conventional cigarettes” in comparison to never smokers who had not used e-cigarettes, 43.9% to 21.5%.
E-Cigarette Use Among High School and Middle School Adolescents in Connecticut: Published in November 2014 in the journal Nicotine & Tobacco Research, “E-Cigarette Use Among High School and Middle School Adolescents in Connecticut” used data from anonymous surveys conducted in four high schools and two middle schools in Connecticut in November 2013 to assess knowledge and use of e-cigarettes. Researchers found that 84.3% of middle school students and 92% of high school students were aware of e-cigarettes. Lifetime use of e-cigarettes was 3.5% and 25.2% for middle and high school students respectively. Among middle school students, 1.5% reported current use of e-cigarettes while the number was 12% for high school students. Interestingly, for middle school students who were lifetime e-cigarette users, “51.2% reported that e-cigarette was the first tobacco product they had tried.” The study found that rechargeable and sweet flavors were the most popular types of e-cigarettes.
Aiding Recruitment or Quitting
In December 2014, The Cochrane Collaboration published, “Electronic cigarettes for smoking cessation and reduction.”In the study, researchers examined 13 trials up until July 2014, focusing specifically on two trials that assigned people to treatment groups, comparing e-cigarettes with and without nicotine. The trials were conducted in New Zealand and Italy with a combined sample size of 662 participants. Both trials assessed whether people had attempted to quit smoking for at least six months and used early models of e-cigarettes that contained low nicotine content. In one study, people did not want to quit smoking while in the other study, which also compared e-cigarettes to nicotine patches, people wanted to quit smoking. Based upon the results from these two studies, researchers noted that use of e-cigarettes that contains nicotine “increased the chances of stopping smoking long-term compared to using e-cigarettes without nicotine.” In addition, e-cigarette use with nicotine was found to help smokers “reduce the amount they smoked by at least half compared to using an e-cigarette without nicotine.” From the findings available, researchers could not determine if e-cigarettes were more successful than nicotine patches in helping people quit smoking due to a low sample size. However, the original study did indicate that people who used e-cigarettes were more likely to reduce the amount they smoked “by at least half than people using the patch.” The researchers called for future studies to assess the effectiveness of e-cigarettes in helping people quit smoking.
At the same time, other experts in public health have expressed concern that e-cigarettes are a gateway for young individuals to start using real cigarettes. In December 2014, “Risk Factors for Exclusive E-Cigarette Use and Dual E-Cigarette Use and Tobacco Use in Adolescents” was published in the journal Pediatrics, assessing e-cigarette and cigarette use among adolescents. Researchers in Hawaii collected data in 2013 using a school-based survey from 1,941 high school students. The findings showed that 17% of students only used e-cigarettes, 12% used both, 3% used only cigarettes, and 68% were nonusers. With the survey, researchers also assessed “psychosocial risk and protective variables (eg, parental support, academic involvement, smoking expectancies, peer smoking, and sensation seeking),” finding that dual users and users of only cigarettes were “highest on the risk status (elevated on risk factors and lower on protective factors).” Students who only used e-cigarettes had a higher risk status than nonusers but were lower than dual users. The researchers concluded that because e-cigarette only users “were intermediate in risk status between nonusers and dual users” it “raises the possibility that e-cigarettes are recruiting medium-risk adolescents, who otherwise would be less susceptible to tobacco product use.”
Restrictions and Going Forward
The US FDA currently does not regulate e-cigarettes, but it has begun the process. Proposed FDA regulation would force manufacturers of e-cigarettes to win “premarket” approval of their products in two years or remove the products from the market. In a letter on November 24, 2014, House Speaker John Boehner (R-Ohio), House Majority Leader Kevin McCarthy (R-California), and House Energy and Commerce Committee Chairman Fred Upton (R-Michigan) wrote to Health and Human Services Secretary Sylvia Burwell asking for changes to the scheduled FDA regulations on e-cigarettes and calling for existing e-cigarette products to be able to remain on the market.
States have also taken action against e-cigarettes. A study, “State Laws Prohibiting Sales to Minors and Indoor Use of Electronic Nicotine Delivery Systems (ENDS),” was released from the CDC in December 2014. Researchers examined state laws finding that as of November 30, 2014, “40 states prohibited ENDS sales to minors, but only three states prohibited ENDS use in private worksites, restaurants, and bars.”
E-cigarettes are growing in popularity in the United States, particularly among young individuals. According to an analysis by Wells Fargo Securities, the firm estimates that in 2014, sales of e-cigarettes in the US reached roughly $1.7 billion. Research is continuing to be conducted examining the effects of e-cigarette use. Hopefully with a better understanding of the impact of e-cigarettes, states and the FDA will respond with appropriate restrictions and regulations.