There is little documented evidence regarding the oral effects of e-cigarette use. In one 2011 study, Polosa, et al, 32 found 6% of patients reported mouth irritation; 8% sore throat and dry mouth; and 9% mouth ulcers after 4 weeks of use. After 8 weeks, 8% reported coughing and after 24 weeks, 8% had throat irritation and 7% dry mouth.
The FDA posts adverse event reports it has received concerning electronic cigarettes since 2008. To date, 115 adverse events concerning e-cigarettes have been reported, including four reports of mouth irritation and/or gums bleeding.
It is well known traditional cigarettes have many health risks associated with its use. Upon inhalation of tobacco smoke, the dry heat produced from the cigarette causes a hypoxic (dry) environment that is detrimental to the oral cavity. If there are, in fact, no toxic chemical substances in the ENDS solution, but the smog production causes a dry environment within the oral cavity, are e-cigarettes a better alternative?
At this time, overall research demonstrates a relatively low incidence of adverse oral effects; however, more long-term studies are needed to fully assess this device.
Systemic effects of e-cigarette use also needs further research. Goniewicz, et al,33 evaluated the vapors from 12 brands of e-cigarettes. The study found the vapors contained 9-450 times lower toxic substances than that of traditional tobacco cigarettes. However, although data is limited, it is clear that e-cigarette emissions are not merely “harmless water vapor,” as is frequently claimed, and can have negative health impacts and be a source of indoor air pollution.
The nicotine levels in the blood stream are unclear and vary depending on the research. Levels range from a similar level to that of cigarettes and others indicate a lower blood nicotine level. More research is indicated in this area.
It is known that nicotine, at high levels, can be lethal. ENDS cartridges contain concentrated nicotine, ranging from 6mg-24mg. If a child were to ingest the nicotine from an ENDS cartridge, acute nicotine poisoning, and possibly death, could result.34 Indeed, in April 2014, a CDC study reported that the number of calls to poison centers involving e-cigarette liquids containing nicotine rose from one per month in September 2010 to 215 per month in February 2014.
It is suggested both duration (years of cigarette use) and intensity (cigarettes per day) determine the negative health effects of smoking.
The 2014 report of the US Surgeon General concluded that “reducing the number of cigarettes smoked per day is much less effective than quitting entirely for avoiding the risks of premature death from all smoking-related causes of death.”
Use of electronic cigarettes by cigarette smokers to cut down on the number of cigarettes smoked per day is likely to have much smaller beneficial effects on overall survival compared with quitting smoking completely.
This situation is particularly likely to exist for cardiovascular disease. Light smoking, even 1 to 4 cigarettes per day, is associated with markedly elevated risk of cardiovascular disease.65 In addition, e-cigarettes deliver loads of fine particles similar to those of conventional cigarettes. Above certain intensity, the specific levels of exposure may not cause significant differences in risk for cancer. Doll and Peto66 found a dose-response relationship between duration of smoking and number of cigarettes smoked per day and risk of lung cancer, with models suggesting the impact of duration to be greater than that of intensity. Using participants from the Cancer Prevention Study II, Flanders et al67 found a greater increase in lung cancer mortality with a greater duration of cigarette smoking compared with a greater intensity of smoking. Overall, this data suggest that lung cancer mortality increases more with additional years of smoking than additional cigarettes per day. Thus, if dual use of e-cigarettes and cigarettes results in reductions in the number of cigarettes per day for current smokers, any reduction malignancy risk will be less than proportional to the reduction in cigarette consumption because of the (likely larger) importance of duration of smoking.
“Even though e-cigarettes are known to be much less harmful for health than tobacco smoking products, nobody knows what their long-term health and addiction consequences might be.” – Roswell Park Cancer Institute, Buffalo, New York