The Eurobarometer data for 2012 indicates that 69% of Europeans have heard of the EC. Data in Anglo-Saxon countries show that 73 and 54% of American and English citizens, respectively, know the EC, while knowledge of these devices is less than 35% of Canadian and Australian citizens. It is noteworthy that in these 2 countries the sale and distribution of the EC is prohibited.
In the United States, sales of CE and those of the “bottles containing filling liquids” increased, from 2010 to 2012, 9 and 14 times, respectively. The dissemination and marketing that these products have had in the United States have been spectacular. Suffice it to say that during the awards ceremony of the 2010 Grammy Awards the EC were delivered as a gift among those attending it, and have even been promoted in some American films.
The same increase in sales observed in the United States has been seen in the United Kingdom, where CE sales increased from a few thousand in 2006 to 600,000 in 2012. Each year sales rose 500%. In some countries, this increase in sales has not been maintained over time. In Italy, EC sales increased for a year, but then progressively decreased.
The EC market in Europe is very fragmented and is led by small companies. However, large tobacco companies are very interested in this product. In 2012, the American tobacco company Lorillard bought one of the leading CE companies in America (Blu e-Cigs). At the present time other large tobacco companies, such as Reynolds American Inc., BAT and Philip Morris, are researching and developing new products of the CE type.
With regard to the chemicals that are present in the EC, 2 aspects have to be considered. On the one hand, the substances that are contained in the liquid with which the EC is charged; on the other hand, those that are produced as a result of the heating of said liquid and that are vehiculized through the steam emitted by the EC.
The liquid with which the EC is loaded contains the following substances: propylene glycol, glycerin, nicotine, flavorings (tobacco, mint, fruits, cinnamon, etc.) and other additives.
Propylene glycol is the fundamental component of the liquid. This substance is considered safe for use as ingested substance. However, there is not much information about its safety when inhaled, as is the case with the EC. There is some study that shows that prolonged inhalation can cause irritation of the eyes, throat and airways, as well as asthma in children. It should be assumed that EC consumers would be exposed to inhalation of this substance throughout the day and for a more or less prolonged time. This could be particularly dangerous for subjects with basic respiratory problems. In fact, some of the CE producers warn about this aspect in their products.
Glycerin is another of the fundamental components of EC fluids. This substance is considered safe when consumed orally. However, its effects are not known when it is inhaled. A recent article showed the case of a woman of 42years old who had been consuming EC for 7months and he developed a subacute picture of fever, cough and dyspnea. Analysis of sputum and bronchoalveolar lavage samples revealed macrophages loaded with lipids. The patient’s condition was diagnosed with lipoid pneumonia. The abandonment of EC consumption resulted in an improvement and disappearance of its pathology.
EC fluid contains nicotine in doses ranging from 0 to 36mg / ml The main problem that can produce this is that, due to the manipulation that is done with the liquid to introduce it into the atomizer, part of this nicotine can come into contact with the skin and cause irritation or can be ingested, accidentally, by children. It is known that the intake of a dose of only 6mg can be lethal to them.
The steam emitted by the EC is also loaded with chemicals that may pose a health risk. Among them, the following stand out: formaldehyde, acetaldehyde and acroleins, although in smaller quantities than in cigarette smoke. On the other hand, metals such as nickel, chromium and lead have been found in the EC steam. It is believed that they are produced from atomizers.
It is noteworthy that the levels of nickel found in the EC vapor are higher than those detected in cigarette smoke. The International Agency for Research on Cancer classifies all these substances as carcinogenic without determining a safety threshold for their consumption.
One study analyzed the acute effects on the respiratory system caused by the inhalation of an EC during 5min in 30 healthy smokers. The study showed that such inhalation did not produce effects on basic lung parameters such as FEV 1 , FVC, PEF and MEF 50-75%. However, it did cause a reduction in exhaled nitric oxide levels and an increase in peripheral airway resistance and impedance. While both reducing nitric oxide levels (from 2.14ppb, p=0.005) as the increase in resistance and impedance (of 0.04kPa / (l / s), p=0.003) were significant, had no acute clinical translation. However, its long-term clinical significance could not be assessed or ruled out. At the moment there is a significant absence in the literature of serious works that evaluate the effects in the short, medium and long term that could have EC consumption on lung function.
The use of EC emits substances into the environment. Among them, propylene glycol and nicotine have been detected, as well as liquid particles of less than 2.5μm in diameter (PM2.5). This type of particles can penetrate the lungs and cause damage associated with passive EC consumption in non-“vaping” subjects. In one study, the emission of these particles to the environment was assessed with the consumption of CE and conventional cigarettes. The results showed that the amount that appeared after the use of conventional cigarettes was much higher than what was detected after the consumption of the EC (901μg / m for conventional cigarettes versus 43μg / m for the EC). It should be noted that the safety threshold dictated by WHO for this type of substance is slightly below 43μg / m.
In this section we will analyze the studies that have been carried out with the objective of measuring the effectiveness of the EC as a device to help tobacco cessation. In this sense there are several types of studies: those that measure the effectiveness they have in controlling the different symptoms of withdrawal symptoms, and those that have been designed to evaluate the effectiveness of this product to achieve complete withdrawal.