In a major scientific review of research on e-cigarettes, UC San Francisco scientists found that industry claims about the devices are unsupported by the evidence to date, including claims that e-cigarettes help smokers quit.
Toxins and nicotine have been measured in that aerosol, such as formaldehyde, acetaldehyde, acetic acid and other toxins
- Formaldehyde is a colorless, flammable, strong-smelling chemical that is used in building materials and to produce many household products.
- Formaldehyde sources in the home include pressed-wood products, cigarette smoke, and fuel-burning appliances.
- When exposed to formaldehyde, some individuals may experience various short-term effects.
- Formaldehyde has been classified as a known human carcinogen (cancer-causing substance) by the International Agency for Research on Cancer and as a probable human carcinogen by the U.S. Environmental Protection Agency.
- Research studies of workers exposed to formaldehyde have suggested an association between formaldehyde exposure and several cancers, including nasopharyngeal cancer and leukemia.
Individuals may experience adverse effects such as watery eyes; burning sensations in the eyes, nose, and throat; coughing; wheezing; nausea; and skin irritation. formaldehyde exposure is associated with certain types of cancer. The International Agency for Research on Cancer (IARC) classifies formaldehyde as a human carcinogen (2). In 2011, the National Toxicology Program, an interagency program of the Department of Health and Human Services, named formaldehyde as a known human carcinogen in its 12th Report on Carcinogens (3).
It has a general narcotic action and large doses can even cause death by respiratory paralysis. It may also cause drowsiness, delirium, hallucinations, and loss of intelligence. Exposure may also cause severe damage to the mouth, throat, and stomach; accumulation of fluid in the lungs, chronic respiratory disease, kidney and liver damage, throat irritation, dizziness, reddening, and swelling of the skin.
Acetaldehyde is a carcinogen in humans. In 1988 the International Agency for Research on Cancer stated, “There is sufficient evidence for the carcinogenicity of acetaldehyde (the major metabolite of ethanol) in experimental animals.” In October 2009 the International Agency for Research on Cancer updated the classification of acetaldehyde stating that acetaldehyde included in and generated endogenously from alcoholic beverages is a Group I human carcinogen. In addition, acetaldehyde is damaging to DNA and causes abnormal muscle development as it binds to proteins.
Acetaldehyde is a significant constituent of tobacco smoke. It has been demonstrated to have a synergistic effect with nicotine in rodent models of addiction. Acetaldehyde is also the most abundant carcinogen in tobacco smoke; it is dissolved into the saliva while smoking.
Irritation of the eyes, nose, and upper respiratory tract which could not be tolerated for more than 3 minutes was noted at 816 to 1,226 ppm [von Oettingen 1960]. It has been reported that 50 ppm or more is intolerable to most persons due to intense lacrimation and irritation of the eyes, nose, and throat [AIHA]. It has also been stated that repeated exposures to high concentrations may produce respiratory tract irritation with pharyngeal edema and chronic bronchitis [AIHA 1972].
Inhalation: Burning sensation. Cough. Dizziness. Headache. Laboured breathing. Shortness of breath. Sore throat. Symptoms may be delayed
Acetic acid (aqueous), Ethanoic acid, Glacial acetic acid (pure compound), Methanecarboxylic acid [Note: Can be found in concentrations of 5-8% in vinegar.]
The devices, which are rapidly gaining a foothold in popular culture particularly among youth, are marketed as a healthier alternative to tobacco smoking, as an effective tool to stop smoking, and as a way to circumvent smoke-free laws by allowing users to “smoke anywhere.” Often the ads stress that e-cigarettes produce only “harmless water vapor.”
But in their analysis of the marketing, health and behavioral effects of the products, which are unregulated, the UCSF scientists found that e-cigarette use is associated with significantly lower odds of quitting cigarettes. They also found that while the data are still limited, e-cigarette emissions “are not merely ‘harmless water vapor,’ as is frequently claimed, and can be a source of indoor air pollution.”
The long-term biological effects of use are still unknown, the authors said.
In tackling the question of whether e-cigarette use is helping or harming the nation’s tobacco control efforts, the authors analyzed 84 research studies on e-cigarettes and other related scientific materials.
They concluded that e-cigarettes should be prohibited wherever tobacco cigarettes are prohibited and should be subject to the same marketing restrictions as conventional cigarettes.
The paper is published May 12, 2014 in the American Heart Association’s journal Circulation.
E-cigarettes deliver a nicotine-containing aerosol popularly called “vapor” to users by heating a solution commonly consisting of glycerin, nicotine and flavoring agents. E-liquids are flavored, including tobacco, menthol, coffee, candy, fruit and alcohol flavorings.
Despite many unanswered questions about e-cigarette safety, the impact on public health, and whether the products are effective at reducing tobacco smoking, e-cigarettes have swiftly penetrated the marketplace in the United States and abroad in both awareness and use. Sold by the major multinational tobacco and other companies, the devices are aggressively marketed in print, television and the Internet with messages similar to cigarette marketing in the 1950s and 1960s, even in the U.S. and other countries that have long banned advertising for cigarettes and other tobacco products.
In one indication of the swiftness by which the devices have been embraced, in the U.S. youth “ever use” of the devices rose from 3.3 percent in 2011 to 6.8 percent the following year; in Korea, youth “ever use” of e-cigarettes rose from .5 percent in 2008 to 9.4 percent in 2011. “Ever use” means whether one has smoked the product even just once.
Furthermore, most adults and youths who use e-cigarettes are engaging in “dual use” — smoking both e-cigarettes and conventional cigarettes.
While most youth using e-cigarettes are dual users, up to a third of adolescent e-cigarette users have never smoked a conventional cigarette, indicating that some youth are starting use of the addictive drug nicotine with e-cigarettes.
The report also tackles secondhand exposure.
“E-cigarettes do not burn or smolder the way conventional cigarettes do, so they do not emit side-stream smoke; however, bystanders are exposed to aerosol exhaled by the user,” said the authors. Toxins and nicotine have been measured in that aerosol, such as formaldehyde, acetaldehyde, acetic acid and other toxins emitted into the air, though at lower levels compared to conventional cigarette emissions.
One study of e-cigarettes was conducted to resemble a smoky bar: the researchers found that markers of nicotine in nonsmokers who sat nearby was similar for both cigarette smoke and e-cigarette aerosol exposure. Short-term exposure studies of e-cigarette use show a negative impact on lung function and bystanders absorb nicotine from passive exposure to e-cigarette aerosol, the authors report.
While early research found that e-cigarettes resulted in lower levels of plasma nicotine than conventional cigarettes, more recent research demonstrated that experienced users can attain nicotine absorption similar to that with conventional cigarettes.
When UCSF scientists pooled the results of five population-based studies of smokers, they found that smokers who used e-cigarettes were about a third less likely to quit smoking than those who did not use e-cigarettes. Whether e-cigarette use prevents attempts to quit or whether people who choose to use e-cigarettes are more highly dependent and therefore have a harder time quitting remains to be determined.
The scientists said their research illustrates the need for product regulation.
“While it is reasonable to assume that, if existing smokers switched completely from conventional cigarettes (with no other changes in use patterns) to e-cigarettes, there would be a lower disease burden caused by nicotine addiction, the evidence available at this time, although limited, points to high levels of dual use of e-cigarettes with conventional cigarettes, no proven cessation benefits, and rapidly increasing youth initiation with e-cigarettes,” the authors wrote.
“Furthermore, high rates of dual use may result in greater total public health burden and possibly increased individual risk if a smoker maintains an even low-level tobacco cigarette addiction for many years instead of quitting.”
Electronic cigarettes (E-cigarettes) are devices that deliver nicotine to a user by heating and converting to an aerosol a liquid mixture typically composed of propylene glycol, vegetable glycerin, flavoring chemicals, and nicotine. E-cigarettes are aggressively advertised on television, on the radio, on the Internet, and in magazines, and e-cigarettes companies sponsor sporting events and music festivals. Users inhale a heated propylene glycol or glycerin-based solution for which there are no long-term studies. A short-term exposure study showed that 5 minutes of e-cigarette use resulted in a significant increase in airway flow resistance, which, although of unknown clinical significance, does not support the claim the product is harmlessNonsmokers (persons who do not use tobacco cigarettes or e-cigarettes) who are exposed to the exhaled, or secondhand, e-cigarette aerosol have measurable levels of the nicotine metabolite cotinine in their blood.1
Smoke-free policies are a critical intervention both to protect nonsmokers and to support smoking cessation attempts. To avoid reversing the effectiveness of these policies, e-cigarettes should not be used anyplace where smoking cigarettes is not allowed (including in homes that are smoke-free). There is no reason to reintroduce toxins into clean indoor air environments. As of March 2014, more than 100 communities (including New York, Los Angeles, San Francisco, and Chicago) and 3 states (New Jersey, North Dakota, and Utah) included e-cigarettes in their clean indoor air laws.1
As of March 2014, e-cigarettes were not regulated by the US Food and Drug Administration. The product should be regulated by the US Food and Drug Administration, and therapeutic claims (eg, that they are effective for smoking cessation) should be prohibited until such time that the e-cigarette companies provide evidence that, as actually used, e-cigarettes improve cessation success. To prevent youth initiation, e-cigarette advertising should be subject to the same restrictions (including being prohibited on television and radio) as cigarette advertising, and the use of flavors should be prohibited.
Materials provided by University of California – San Francisco. http://www.cancer.gov/cancertopics/factsheet/Risk/formaldehyde , http://www.cdc.gov/niosh/idlh/64197.html , http://www.sciencedaily.com/ , http://circ.ahajournals.org/content/129/19/e490.full
- R. Grana, N. Benowitz, S. A. Glantz. E-Cigarettes: A Scientific Review. Circulation, 2014; 129 (19): 1972 DOI: 10.1161/%u200BCIRCULATIONAHA.114.007667