No One Can Convince the Other: Are E-Cigarettes Safer or Not?

The inventor of electronic cigarettes is Chinese. Ten years ago, Han Li, one of the founders of the company Suyan, invented the modern version of the e-cigarette. Since then, this "cigarette" that does not require a lighter and does not contain over sixty carcinogens has become popular worldwide.

In an interview with French media in 2013, Han Li stated that although he is the inventor of e-cigarettes, he has not made much money due to the large number of knockoffs and similar products on the market.

Over the past decade, the variety of e-cigarette products on the market has been astonishing. According to a study published in July 2014 by researchers including Zhu Shuhong from the University of California, San Diego, as of January 2014, there were 466 e-cigarette brands sold online globally, with 7,764 different flavors, and these numbers continue to rise. In the 17 months prior to January 2014, the number of e-cigarette brands increased at an average rate of 10.5% per month, while the number of flavors increased by 242 each month.

In August 2014, Daniel Sarewitz, a technology policy researcher at Arizona State University, published a commentary in the journal Nature, proposing a thought experiment related to e-cigarettes.

Sarewitz hypothesized what would happen if every smoker in the United States switched to using e-cigarettes. He pointed out that e-cigarettes allow users to continue enjoying the pleasure of nicotine while avoiding inhaling dozens of carcinogens and hundreds of other toxic substances produced by burning tobacco. "If all smokers in the U.S. were to vape e-cigarettes, the 480,000 annual deaths from smoking would ultimately be avoided," he wrote.

Sarewitz is clearly supportive of e-cigarettes, believing that the causal relationship between traditional cigarettes and disease is well established, and that e-cigarettes are currently the best alternative. "Make smoking look uncool, expensive, and stupid, and make using e-cigarettes look cool and smart. If people are going to be addicted to something, let it be something that won't give them or their families cancer," is his viewpoint.

However, Sarewitz's perspective does not represent the majority of researchers. In fact, there is a significant divide among scientists regarding how to view this new phenomenon, with opposing viewpoints unable to convince each other.

Creating More Smokers?

Although businesses often claim in advertisements that e-cigarettes help with quitting smoking, some scientists are quite skeptical. This year, new data has led some researchers to believe that e-cigarettes should be regulated like traditional cigarettes.

In July 2014, Jennifer Duke and colleagues from RTI International published a study reporting on the exposure of American youth to television advertisements for e-cigarettes.

According to Duke's research, television ads for e-cigarettes reached 24 million teenage viewers in the U.S. The frequency with which teens saw e-cigarette ads on television more than doubled from 2011 to 2013, while young adults saw them three times more often.

Other recent studies have also found that e-cigarettes are mentioned extensively on social networks. In just May and June 2012, over 23,000 different users on Twitter posted more than 70,000 tweets related to e-cigarettes, with nearly 90% being commercial in nature.

Researchers are unclear about the proportion of teenagers among Twitter users, but those aged 18 to 29 account for 26%, which is twice the proportion of users aged 30 to 49.

Researchers have also found that the advertising techniques used for e-cigarettes and their allure are increasing.

These latest research findings have led Stanton Glantz from the Tobacco Control and Education Center at the University of California, San Francisco, to believe that controlling e-cigarettes is imperative. In August 2014, he submitted a comment to the FDA stating, "The FDA should prohibit advertisements and promotions that claim or imply that e-cigarettes are safer than traditional cigarettes or are effective smoking cessation tools until manufacturers can provide sufficient evidence to the FDA that these claims are true."

Glantz has been calling for controlling the depiction of smoking among youth for several years, including criticizing smoking scenes in the movie Transformers: The Last Knight, stating that they harm American youth, and that there are even more young viewers in China than in the U.S.

In March 2014, Glantz and colleagues published a paper stating that their findings show e-cigarettes do not encourage youth to stay away from cigarettes; rather, they may encourage youth to become users of traditional cigarettes. They found that teenagers who use e-cigarettes are more likely to use traditional cigarettes compared to their peers who do not use e-cigarettes.

This research conclusion sparked intense debate among his peers, and the journal that published Glantz's paper subsequently published a series of critical responses. The questioning researchers argued that the data provided by Glantz does not support his conclusion, and that he conflated correlation with causation: although there is overlap between the populations of traditional cigarette users and e-cigarette users, this does not determine whether e-cigarettes induce people to use traditional cigarettes or vice versa.

Glantz later stated in an interview with Nature that those questioning researchers did not accurately understand his paper, and he still insists that his conclusion is supported by data. He believes that e-cigarettes are leading more children to use nicotine and also leading more children to start smoking traditional cigarettes.

In a set of data published in 2013, the CDC stated that from 2011 to 2012, the proportion of high school students in the U.S. who had tried e-cigarettes rose from 4.7% to 10%.

Accordingly, CDC Director Tom Frieden publicly stated, "The rise in e-cigarette use among youth is deeply concerning." He also said, "Nicotine is a highly addictive drug. Many youths who start with e-cigarettes may become addicted to nicotine and traditional cigarettes for the rest of their lives."

However, researchers with opposing views argue that teenagers like to try new things—this is what the data reveals. They believe that the current data is insufficient to support Frieden's claims. In this regard, Nature wrote: "If they (e-cigarettes) were leading people to use traditional cigarettes, then smoking rates should have already risen... This does not seem to have happened—overall smoking rates are declining in developed countries."

Are They Harmful?

Another core issue of heated debate among tobacco and health researchers is whether e-cigarettes are safe, or whether they pose certain threats to human health.

The American Cancer Society's stance on e-cigarettes is: "Until e-cigarettes are scientifically proven to be safe and effective, the American Cancer Society supports regulating them like traditional cigarettes." In July 2014, the American Thoracic Society issued a statement saying, "The safety of e-cigarettes has not been adequately established... The addictive properties of nicotine and its abnormal effects should not be underestimated." A large number of lawyers also jointly wrote to the FDA, further stating that "e-cigarettes should be considered harmful and addictive."

These claims were dismissed by Sarewitz as "nonsense." In his thought experiment, substituting traditional cigarettes with e-cigarettes clearly has more benefits than drawbacks.

Regarding the safety of e-cigarettes, there are indeed some concerns in the scientific community, but current research results make it difficult for experts to determine how safe they really are.

For example, aside from the health effects of nicotine, researchers are concerned about another substance: propylene glycol. This substance is key to the vapor produced by e-cigarettes; it is actually similar to the smoke-producing substances used on stage. Propylene glycol is generally considered safe in most cases, but at high concentrations, such as on stage, it can irritate the respiratory system. The scientific community lacks research on the long-term effects of inhaling propylene glycol.

In April 2014, at the American Association for Cancer Research annual meeting, a group of researchers from Boston University reported that they found gene expression in bronchial cells exposed to moderate concentrations of e-cigarette vapor to be similar to that of cells exposed to tobacco smoke. In this regard, there is no difference between the two.

However, since this is an early-stage study, researchers cannot conclude whether e-cigarettes could cause cancer. "They may be relatively safe, but our preliminary findings show they are not benign either," the researchers stated at the time.

A recent report in Nature also mentioned a study published this year that found that using e-cigarettes, like using traditional cigarettes, reduces the amount of carbon monoxide exhaled by users, which may indicate changes in lung function.

These are early studies on e-cigarettes. The commonality among these studies is that they seem to show that e-cigarettes are not as safe as people think, but the research results are not conclusive.

Many scientists do not believe that current scientific research can provide answers to the dilemma surrounding e-cigarettes. Amid the debate, restrictions on e-cigarettes have already begun.

A number of leading scientists in e-cigarette research wrote to the World Health Organization (WHO) in May 2014, stating that restricting e-cigarettes would be counterproductive, effectively protecting the traditional cigarette market. However, in August, the WHO still published a report recommending limiting the use of e-cigarettes indoors, banning the production of certain flavors, and restricting the sale of e-cigarettes to adults over 18.

Earlier, the European Union amended its tobacco product policies, imposing restrictions on the production standards and advertising of e-cigarettes. Singapore and Brazil have completely banned e-cigarettes. The FDA in the U.S. is attempting to regulate e-cigarettes like traditional cigarettes.

Currently, there are no special restrictions on e-cigarettes in China, meaning there are neither industry standards nor regulatory mechanisms.