11mg E-liquid from Totally Wicked is available in a range of e-juice flavours with a % nicotine strength, made using the highest quality pharmaceutical grade. An electronic cigarette or e-cigarette is a handheld electronic device that simulates the experience of smoking a cigarette. It works by heating a liquid which generates an aerosol, or "vapor", that is . Among those who had never smoked, % said they had tried them and % still use them. In France in , between Find great deals for 5 X Gamucci Premium E-liquid Menthol Ml Nicotine 10 Ml . Shop with confidence on eBay!.
is E-liquid? What 1.1
Internet sales are booming. Playle's French-born assistant, Joelle Tabone "Vaping is huge in France; every small town has at least one shop" , explains how they work. As you puff, the battery at the far end of the device powers a tiny electronic heating element, the atomiser, contained in the clear, refillable cartridge the "clearomizer" attached to the mouthpiece.
The e-liquid in the clearomizer, drawn on to the heating element by fibre wicks, disappears in a cloud of scented vapour, some of which you inhale the rest evaporates. The e-juice is available in three different nicotine strengths, and more sophisticated devices also let users adjust their e-cigarette's voltage to vary the potency of the "hit" they get.
The idea, essentially, is that e-cigarettes deliver all the sensations of smoking, plus the all-important nicotine, without the odd carcinogenic chemicals that tobacco cigarettes generally deliver as well. Logically, by far their biggest users are smokers.
According to Ash's survey, nearly two-thirds of e-cigarette users in the UK are current smokers seeking to cut down or give up altogether, while the remaining third are ex-smokers who have already stopped and are keen not to restart. That certainly chimes with Playle's experience: So far, so marvellous: By the World Health Organisation's estimates , tobacco kills half its users and six million people each year die from the direct and indirect effects of smoking.
But the public health community is deeply divided over e-cigarettes. As far as the health risk is concerned, it is fair to say, as Gilmore notes, that "e-cigarettes are certain to be way less harmful than cigarettes. Common sense would dictate that. The World Health Organisation WHO calls the devices' safety "illusive", noting that the chemicals they contain are often not disclosed and have not been properly tested.
The US Federal Centers for Disease Control CDC has said there is "enough evidence" to say that switching to electronic cigarettes would "likely be healthier" than smoking. But mainly because of the near complete lack of regulatory oversight, and because e-cigarettes do, after all, contain nicotine, which is far from being a "benign substance", the CDC will not go so far as to pronounce them safe either. The British Medical Association BMA has also warned it is worried by the lack of peer-reviewed studies on e-cigarette safety, and public health officials elsewhere have expressed concerns about the purity of the products' ingredients, the precise dose of nicotine delivered by different devices and liquids, inaccurate product labelling and an overall lack of quality control in the manufacturing process.
We cannot say e-cigarettes are risk-free. We cannot yet be sure what impact they will have on smoking rates or population health, whether they'll be the miracle product or not. Nor is there unanimous agreement among public health experts that e-cigarettes even help people to give up smoking. Similarly, the BMA currently encourages doctors to recommend other nicotine replacement therapies ahead of e-cigarettes although it says that for patients who are unwilling to use nicotine gum or patches, or tried them unsuccessfully, the devices can be presented as a lower-risk option than smoking tobacco.
UK studies seem to suggest little evidence that e-cigarettes might have this effect. But in a study of 40, young Americans unambiguously entitled E-Cigarettes: Figure 4 a,b show, respectively, a typical power and resistor profile obtained with the U-SAV.
Two main phases can be observed for both of these curves. The two curves follow the same trend since the power value has been regulated with reference to the resistor value, calculated from measurements of voltage and current.
As the resistor value is linked to its temperature stainless steel wire has a high temperature coefficient of resistance , it becomes stable only when the temperature reaches a plateau value around 1. However, between the transient slope and the complete stabilisation of the temperature, resistor value does not change substantially approximately 0. Power applied to the resistor a and resistor value b during a typical puff. Figure 5 displays separately for each U-SAV line the average power applied over puffs.
The power applied is close to Average power applied from each U-SAV line over puffs during 24 manipulations dark dots. Another option of the U-SAV allows for controlling the electrical energy delivered through voltage regulation. Figure 6 displays the voltage a , power b and resistor value c during one puff in this mode. The voltage was set at 3. However, the corresponding power applied appears to stabilise at Voltage applied to the resistor a , corresponding power applied b and resistor value c during a typical puff.
Figure 7 represents, the average voltage applied from each U-SAV line over puffs during 24 manipulations. Average voltage applied from each U-SAV line over puffs during 24 manipulations dark dots. The results of the average consumption of liquids A and B, as well as their deviation, during an experiment with U-SAV programed in power mode, are presented in Table 1.
The average consumption of liquid A is higher than the one for liquid B by 1. The results of average consumption of liquids A and B during the experiment in voltage mode are presented in Table 2. It should be noted that liquid consumption per puff is lower for voltage than for power modes.
Three batteries for each commercial reference were plugged into U-SAV. Each experiment was performed twice. As shown in Table 3 , for the same power setting 15 Watts , the true average power applied is lower for the two batteries tested than for U-SAV. Additionally, both devices applied lower average power compared to the U-SAV, but the difference was only 1. The average consumption is lower for both commercial batteries than for U-SAV, which is expected considering the observations on power regulation and delivery.
We have observed the resistor value of the atomizer varies during a puff Figure 4 b. The transient slope observed during the first ms is due to a fast temperature elevation that increases the resistor value. The plateau reached after ms is the consequence of a thermal balance between the energy delivered by the battery and the energy collected by the surrounding environment.
The behaviour of a wire in a convective exchange between the environment and an electrical source has a thermal balance that is shown in Equation 1 [ 18 , 19 , 20 ]:. Equation 2 determines the rise of temperature in the resistor. We have built our hypothesis on the fact that the temperature of vaporization of the liquid limits the temperature of the resistor PG: Thus, referring to Equation 2 , the resistor will reach a thermal balance around 0.
This is confirmed by the resistor profile shown on Figure 4 b. Indeed, the transient slope occurs during the initial ms of the puff. Then, the resistor enters in a saturation stage Equation 3 and begins to stabilize until it reaches the value of 1. Based on continuous every ms resistor measurements and the power set on the U-SAV, a new voltage value is calculated and is applied in order to regulate the electrical power and maintain it at the value programmed by the operator. This is particularly critical during the transient response since the resistance value changes considerably and this is the reason why the power applied during this phase is lower than the power set during the transient response phase.
However, the power regulation is very accurate when the resistor reaches a constant temperature. The stability and repeatability of the power delivery makes it possible to have repeatable conditions for aerosol generation. In voltage mode, the programmed voltage is calculated using the manufacturer resistor value.
However, U-SAV does not perform any voltage adjustments in relation to the resistance value change during the puff. Thus, the applied power changes from to This represents a significant deviation from the expected value 15 W and explains the difference between set and true measured power as shown in Figure 6 b. Resistor profiles, from power mode Figure 4 b and voltage mode Figure 6 c , are similar, and shows that the power difference between the two modes does not have any influence on the temperature reached by the resistor.
However, liquid consumption between the two different modes was different. This experiment proves that it is extremely important to have full monitoring of the aerosolization process. Likewise, it is essential to have the possibility to alter the voltage supply to the atomiser in order to have a constant and accurate power delivery to the resistor.
These observations have implications in the regulatory setting when comparing efficiency or nicotine release from different devices. Each of the two batteries from different commercial brands was tested for stability of the power supplied and repeatability of the e-liquid aerosolised.
However, the observed difference has a direct impact on the average consumption of e-liquid. This should be taken into consideration when evaluating device efficiency or comparing findings between different laboratories.
Despite consistent delivery of power throughout the experimental session puffs in this study , still there was a substantial difference between the desired and the true power delivery. This is a major issue in the study of vaping products. A battery can present a good stability for energy supplied and mass of aerosolized e-liquid but have a relevant deviation in comparison with the instructions asked.
The U-SAV vaping machine takes less than 50 ms to reach the set value for flow rate. The rapidity and stability of controlling airflow rate with U-SAV allows creating a square-wave air flow profile. The power supply, air flow rate and mass variation of liquids A and B were tested and verified.
Thus, these results validate both the U-SAV machine and the Cubis atomiser for their utilization in research or for comparative studies and even for regulatory purposes. We present in this study a novel vaping machine, U-SAV, which has the ability to generate, control and measure the electrical energy supplied to the resistor. The different experiments showed excellent reproducibility of the electrical parameters and of the applied airflow rate and an acceptable repeatability for the mass of aerosolised e-liquid.
Our study demonstrates the importance of fully controlling the aerosolisation process. In order to have comparative results between laboratories, the batteries used for the tests must be well characterized and should be validated for their repeatability and consistent performance in order to be used in emission studies.
Indeed, it was shown that even if a commercial battery device is reproducibly delivering power, there may be a significant difference between the power setting and the true power delivery. It should be noted that the batteries used herein have a high capacity and can deliver power consistently over the puffs required in the AFNOR standard. However, for batteries with smaller capacity or when higher power settings are used, the discharge rate will be faster and could affect the stability of the power supply during the experimental session.
It can be used to study the influence of the main physical parameters of EC function such as power, resistor, puff number and duration, and how these parameters affect emissions.
Indeed, the U-SAV interface allows changing several parameters, enabling the characterization of their influence on aerosol emissions. Moreover, U-SAV makes it possible to generate emissions with realistic vaper profiles such as sinusoidal air flow pattern or with the voltage mode that makes no adjustments relative to the change of the resistor value.
U-SAV can also be used with commercial batteries and study their performance characteristics. Additionally, the power mode of USAV can be used to examine emissions under strictly controlled and accurate power delivery settings, to examine atomiser efficiency and to ensure inter-laboratory consistency in aerosol emission testing.
The authors would like to thank all the collaborators who have financed the development and the conception of U-SAV. The collaborators are French actors of vaping products: Helene Lalo and Sebastien Soulet conceived and designed the whole paper. All the authors made substantial, direct and intellectual contribution to the work and approved it for publication.
The LFEL is an actor and a committed defender of the independent vape. National Center for Biotechnology Information , U. Published online Oct Author information Article notes Copyright and License information Disclaimer.
Received Jul 28; Accepted Oct 6. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution CC BY license http: This article has been cited by other articles in PMC. Abstract The accurate study of aerosol composition and nicotine release by electronic cigarettes is a major issue. Introduction The use of electronic cigarettes ECs has grown rapidly as a safer alternative for nicotine consumption than tobacco cigarettes [ 1 ].
Ability to control the electrical energy delivery, either by voltage or by power regulation, using an internal built-in generator; Generation of different flow profiles square, tooth saw, sinusoidal.
Open in a separate window. Materials and Methods 2. Vaping Machine Configuration U-SAV has the distinctive feature to generate and control the electrical energy delivered to the atomiser [ 17 ].
The operator can choose between three different flow profiles square, tooth saw, sinusoidal and different modes: Voltage Regulation Another option of the U-SAV allows for controlling the electrical energy delivered through voltage regulation. Repeatability on the Mass of Aerosolized E-Liquid The results of the average consumption of liquids A and B, as well as their deviation, during an experiment with U-SAV programed in power mode, are presented in Table 1.
WHICH STRENGTH OF CARTOMIZER (REFILL) DO I NEED?
A necessary part of electronic cigarettes is e-liquid, with that in mind, we have provided this section of our site to give users all you need to know more about. The VIP E-Cig Cartomizer strength is a personal preference and will depend largely on Mild 11mg (% per ml) - 10 cigarettes or less per day or trying to limit. Author summary The e-liquids used in electronic cigarettes (E-cigs) pO2 was 20 ± % (n = 3) in control media and 18 ± % (n = 4) after.