Electronic cigarette: Difference between revisions - Wikipedia

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The risks of electronic cigarette use are uncertain.<ref name="Odum2012">{{cite journal|last1=Odum|first1=L. E.|last2=O'Dell|first2=K. A.|last3=Schepers|first3=J. S.|title=Electronic cigarettes: do they have a role in smoking cessation?|journal=Journal of pharmacy practice|date=December 2012|volume=25|issue=6|pages=611–4|pmid=22797832|doi=10.1177/0897190012451909}}</ref><ref name=Harrell2014/> This is due to there being little data regarding their health effects<ref name="Palazzolo">{{Citation | title=Electronic cigarettes and vaping: a new challenge in clinical medicine and public health. A literature review. | url=http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3859972/ | author1-first=Dominic L. |author1-last=Palazzolo | journal=Frontiers in Public Health | volume=1 |issue=56 | date=Nov 2013| doi=10.3389/fpubh.2013.00056 | pmid=24350225 | pmc=3859972}}</ref> and to the variability of vaporizers and variability in liquid ingredients and in their concentration and quality, and thus variability of the contents of mist delivered to the user.<ref name="Grana2014" /><ref name="Odum2012" /><ref name="O2012">{{cite journal|last=O'Connor|first=RJ|title=Non-cigarette tobacco products: what have we learnt and where are we headed?|journal=Tobacco control|date=March 2012|volume=21|issue=2|pages=181–90|pmid=22345243|doi=10.1136/tobaccocontrol-2011-050281|pmc=3716250}}</ref><ref name=CDCQ&A>{{cite web |author=Edgar, Julie |title=E-Cigarettes: Expert Q&A With the CDC |url=http://www.webmd.com/smoking-cessation/news/20131112/e-cigarettes-cdc |publisher=WebMD |accessdate=17 November 2013}}</ref><ref name="FDAPublicHealthFocus">{{cite web|title=Public Health Focus: Electronic Cigarettes (e-Cigarettes)|url=http://www.fda.gov/NewsEvents/PublicHealthFocus/ucm172906.htm|publisher=FDA|date=24 April 2014}}</ref> However, some evidence suggests e-cigarettes may be safer than smoking tobacco products, and possibly as safe as other [[nicotine replacement products]] but there is insufficient data to draw conclusions.<ref name=Grana2014/><ref name="O2012" /> A July 2014 WHO report cautioned about potential risks of using electronic cigarettes.<ref name="WHO Position 2014"/> A 2014 [[systematic review]] concluded that the risks of e-cigarettes have been exaggerated by health authorities and stated that it is apparent that there may be some remaining risk accompanied with e-cigarette use, though the risk of e-cigarette use is likely small compared to smoking tobacco.<ref name=FarsalinosPolosa2014/>

==== Toxicology ====

<!-- Toxicology evidence -->

[[File:Toxicants emitted by tobacco cigarettes and e-cigarettes ehp.122-A244.t001.png|thumbnail|left|Chart showing various toxicants as measured in cigarette and e-cigarette smoke.<ref>{{cite journal|last1=Arnold|first1=Carrie|title=Vaping and Health: What Do We Know about E-Cigarettes?|journal=Environmental Health Perspectives|volume=122|issue=9|year=2014|pages=A244–A249|doi=10.1289/ehp.122-A244|pmc=4154203|pmid=25181730}}</ref>]]

A preliminary analysis of e-cigarette cartridges by the US [[Food and Drug Administration]] (FDA) in 2009 identified that some contain [[tobacco-specific nitrosamines]] (TSNAs), known cancer-causing agents.<ref name=FDA_nitrosamines>{{cite web|title=Safety Watch: Electronic Cigarettes|url=http://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm173327.htm|publisher=FDA}}</ref> The tobacco specific impurities suspected of being harmful to humans were [[anabasine]], [[myosmine]], and β-nicotyrine, they were detected in a majority of the samples.<ref name="FDA Chemical Analysis">{{cite web|url=http://www.fda.gov/NewsEvents/PublicHealthFocus/ucm173146.htm|author=FDA|title=Summary of Results: Laboratory Analysis of Electronic Cigarettes Conducted By FDA|date=22 July 2009|accessdate=22 July 2009}}</ref> The amounts of TSNAs present were on par with existing NRT products like nicotine gum and inhalers. The FDA's analysis also detected [[diethylene glycol]], which is poisonous, in a single cartridge manufactured by Smoking Everywhere and nicotine in one cartridge claimed to be nicotine-free.<ref name=FDA_nitrosamines/><ref name="FDA Study"/> While diethylene glycol was found in a cartridge tested in 2009 by the FDA, in 2011 researchers reviewed the data and noted that 15 other studies had failed to find any evidence of this chemical in e-cigarettes.<ref>{{cite web | url=http://www.ibtimes.com/e-cigarettes-effective-nicotine-patches-helping-smokers-quit-study-1403523 | title=E-Cigarettes As Effective As Nicotine Patches in Helping Smokers Quit: Study | work=[[International Business Times]] | date=8 September 2013 | accessdate=15 December 2013 | author=Palmer, Roxanne}}</ref> The UK [[National Health Service]] noted that the toxic chemicals found by the FDA were at levels one-thousandth that of cigarette smoke, and that while there is no certainty that these small traces are harmless, initial test results are reassuring.<ref name=nhs>{{cite web|title=E-cigarettes to be regulated as medicines |publisher=[[National Health Service]]|date=12 June 2013|accessdate=August 2013|url=http://www.nhs.uk/news/2013/06June/Pages/e-cigarettes-and-vaping.aspx}}</ref> The risks, especially to the lungs, are not fully understood and are of concern to public health authorities and some reviewers.<ref name="NHE2014"/><ref name="WHO2013">{{cite web|title=Electronic cigarettes (e-cigarettes) or electronic nicotine delivery systems|url=http://www.who.int/tobacco/communications/statements/eletronic_cigarettes/en/index.html|work=World Health Organization|date=3 June 2014}}</ref><ref name=IUATLD>{{cite web |title=Position Statement on Electronic Cigarettes [ECs] or Electronic Nicotine Delivery Systems [ENDS] |url=http://www.theunion.org/what-we-do/publications/official/body/E-cigarette_statement_FULL.pdf |format=PDF |date=October 2013 |publisher=The International Union against Tuberculosis and Lung Disease}}</ref> Further concerns were raised over inconsistent amounts of nicotine delivered when drawing on the device.<ref name="FDA Study">{{cite web|url=http://www.fda.gov/downloads/Drugs/ScienceResearch/UCM173250.pdf|author=FDA|title=FDA 2009 Study Data: Evaluation of e-cigarettes|work=Food and Drug Administration (US) -center for drug evaluation and research|date=4 May 2009|accessdate=4 May 2009}}</ref> The risk is probably low from the inhalation of [[propylene glycol]] and [[glycerol]].<ref name=Haj2014/> The composition of inhaled levels of nicotine is not clear.<ref name=Drummond2014/> While there is variability in the ingredients and concentrations of ingredients in e-cigarette liquids, tobacco smoke contains thousands of chemicals, most of which are not understood and many of which are known to be harmful.<ref name=Saitta2014/> A 2014 review stated the [[ultrafine particle|particles are of the ultrafine size]] similar to cigarettes, and go deep in the lungs and then into the [[systemic circulation]].<ref name=Grana2014/> The levels of chemical compounds in the mist were found to be 1 to 2 [[orders of magnitude]] smaller than in cigarette smoke but greater compared to a [[nicotine inhaler]].<ref name=Grana2014/> Reports in the literature have shown respiratory and cardiovascular effects by these smaller size particles, suggesting a possible health concern.<ref name=AIHA2014/> A 2014 review found e-cigarettes emissions contain the [[heavy metals]] nickel, tin, and chromium.<ref name=Grana2014/> These [[nanoparticle]]s can deposit in the [[pulmonary alveoli|lung's alveolar sacs]], potentially leading to local respiratory toxicity and entering the bloodstream.<ref name=Grana2014/> A 2014 review found it can be concluded that there is no evidence of contamination of the aerosol with metals that justifies a health concern.<ref name=Bur2014/> Another 2014 review found that the levels of metals were 10-50 times less than the point where they do harm.<ref name=Haj2014/> A 2014 review found that e-cigarettes used in the short-term on specified cardiovascular and respiratory functional results have demonstrated that even though some minor harmful effects of vaping are documented, these are appreciably milder in comparison to traditional cigarettes.<ref name=FarsalinosPolosa2014/> The [[Centers for Disease Control and Prevention]] (CDC) stated the possible negative impact between nicotine and [[brain development]] in youth is a concern.<ref name=MMWR2013/> A serious concern is the outcome of nicotine on the growing adolescent brain.<ref name=CDCQ&A/> There is no long-term research concerning the cancer risk related to the small level of exposure to the identified carcinogens.<ref name=Drummond2014/> Like cancer risk, there is no literature outlining the long-term lung function or cardiovascular consequences.<ref name=Drummond2014/>

==== Adverse effects ====

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Fine particles can be chemically intricate, and the harmful elements and the importance of the size of the particle and what the particle is made of is mostly unknown, thus it is not clear whether the particles in e-cigarette emissions have health effects similar to those produced by traditional cigarettes.<ref name=Grana2014/>

<!-- Adverse effects -->

E-cigarettes use [[lithium batteries]] most of the time, improper use may result in accidents.<ref name=FarsalinosPolosa2014/> Rare major injuries have occurred from battery malfunctions such as explosions and fires.<ref name=Grana2014/> The explosions resulted either by extended charging and use of unsuitable chargers or by design flaws have occurred.<ref name=FarsalinosPolosa2014/> It is recommended manufacturing quality standards be employed in order to prevent such accidents.<ref name=FarsalinosPolosa2014/> Complaints of less serious [[adverse effect]]s of throat and mouth inflammation, vomiting, nausea, cough have resulted from e-cigarette use.<ref name=Grana2014/> The US [[Regulation of tobacco by the U.S. Food and Drug Administration#Center for Tobacco Products|Food and Drug Administration Center for Tobacco Products]] reported between 2008 and the beginning of 2012, 47 cases of adverse effects associated with e-cigarettes, and eight were considered serious.<ref name=Haj2014/> A causal relationship between e-cigarettes and the reported adverse effects was not established with the exception of two severe outcomes in the United States: a death when an infant choked on the cartridges and burns when one blew up.<ref name=Haj2014/>

In the United States the number of calls to poison control centers related to electronic cigarettes have increased between 2010 and 2014 such that they now represent 42% of reported cases due to either cigarettes and e-cigarettes up from 0.3%.<ref name=Orr2014/> These calls were in connection to both adults and children.<ref name=Orr2014>{{cite journal|last1=Orr|first1=KK|last2=Asal|first2=NJ|title=Efficacy of Electronic Cigarettes for Smoking Cessation.|journal=The Annals of pharmacotherapy|date=November 2014|volume=48|issue=11|pages=1502–1506|pmid=25136064}}</ref> E-cigarettes were associated with fewer adverse effects than nicotine patches.<ref name=Orr2014/> Calls to U.S. [[poison control center]]s related to e-cigarette exposures were inhalations, eye exposures, skin exposures, and ingestion, which included adults and young children.<ref name=MMWR2014>{{cite journal |title=Notes from the field: calls to poison centers for exposures to electronic cigarettes--United States, September 2010-February 2014 |journal=MMWR Morb. Mortal. Wkly. Rep. |volume=63 |issue=13 |pages=292–3 |date=April 2014 |pmid=24699766 |url=http://www.cdc.gov/mmwr/preview/mmwrhtml/mm6313a4.htm |author1= Centers for Disease Control and Prevention (CDC)}}</ref> The California Poison Control System reported from 2010 to 2012, 35 cases of e-cigarette contact.<ref name=FarsalinosPolosa2014/> 14 were from children and 25 were from accidental contact.<ref name=FarsalinosPolosa2014/> The majority of adverse effects reported were nausea, vomiting, dizziness and oral irritation.<ref name=FarsalinosPolosa2014>{{cite journal|last1=Farsalinos|first1=K. E.|last2=Polosa|first2=R.|title=Safety evaluation and risk assessment of electronic cigarettes as tobacco cigarette substitutes: a systematic review|journal=Therapeutic Advances in Drug Safety|volume=5|issue=2|year=2014|pages=67–86|issn=2042-0986|doi=10.1177/2042098614524430|pmid=25083263}}</ref>

===Aerosol===