Chemical Constituents in E-Cigarette Liquids and Aerosols

Electronic cigarettes (e-cigarettes, EC) form an aerosol from the heating element and liquid-containing cartridge. The heating element aerosolizes the refill solutions (e-liquids) when the power source of e-cigarette is pressed. E-liquids consist of combinations of propylene glycol, glycerine, nicotine and flavouring ingredients. Puffing activates the battery-operated heating element in the atomizer and will produce smoke that is similar to conventional cigarette (CC). This study evaluated the chemical composition of e-liquid and aerosol samples available in Malaysia. We analyzed the volatile organic compounds in e-liquids and the aerosols samples from EC using gas chromatography mass spectrometer. Seventy-two EC e-liquids were analyzed through different flavours from more than 60 brands. Samples consisted of 32 nicotine-free (0 mg) and 40 nicotine-containing refill solutions (3 - 12 mg). Overall, 116 compounds were identified from EC e-liquids. On the other hand, 275 compounds were identified from their resultant aerosol samples. There were 42 compounds found in both e-liquids and aerosols. Seven compounds were only found in e-liquids and 38 compounds were only found in aerosols. Propylene glycol was found in all of the e-liquid and aerosol samples. Glycerin was found in 99% of the e-liquid and 100% of aerosol samples. At least 60% of the EC e-liquids and the resultant aerosol contain piperidine, butanoic acid ethyl ester and nicotine. It was also found that at least 9 out of 35 nicotine free labeled e-liquids contain nicotine. Some of these compounds were known to be detrimental to health and were detected in aerosol although they were not present in e-liquids. While some of the compounds are flavouring ingredients, it is necessary to evaluate its long-term effects on EC users.

Attitudes toward E-Cigarettes, Reasons for Initiating E-Cigarette Use, and Changes in Smoking Behavior after Initiation: A Pilot Longitudinal Study of Regular Cigarette Smokers

Objectives: We examined 1) changes in smoking and vaping behavior and associated cotinine levels and health status among regular smokers who were first-time e-cigarette purchasers and 2) attitudes, intentions, and restrictions regarding e-cigarettes. Methods: We conducted a pilot longitudinal study with assessments of the aforementioned factors and salivary cotinine at weeks 0, 4, and 8. Eligibility criteria included being ≥18 years old, smoking ≥25 of the last 30 days, smoking ≥5 cigarettes per day (cpd), smoking regularly ≥1 year, and not having started using e-cigarettes. Of 72 individuals screened, 40 consented, 36 completed the baseline survey, and 83.3% and 72.2% were retained at weeks 4 and 8, respectively. Results: Participants reduced cigarette consumption from baseline to week 4 and 8 (p’s < 0.001);23.1% reported no cigarette use in the past month at week 8. There was no significant decrease in cotinine from baseline to week 4 or 8 (p’s = ns). At week 8, the majority reported improved health (65.4%), reduced smoker’s cough (57.7%), and improved sense of smell (53.8%) and taste (50.0%). The majority believed that e-cigarettes versus regular cigarettes have fewer health risks (97.2%) and that e-cigarettes have been shown to help smokers quit (80.6%) and reduce cigarette consumption (97.2%). In addition, the majority intended to use e-cigarettes as a complete replacement for regular cigarettes (69.4%) and reported no restriction on e-cigarette use in the home (63.9%) or car (80.6%). Conclusions: Future research is needed to document the long-term impact on smoking behavior and health among cigarette smokers who initiate use of e-cigarettes.

E-Cigarette: A New Tobacco Product for Schoolchildren in Paris

Objectives: To explore if the dramatic decrease in price of e-cigarette has transformed this new product into a product used for tobacco initiation among a teenage population. Methods: The authors added a question in 2012 on e-cigarette in the yearly survey on tobacco consumption in Paris schoolchildren. The study is conducted on a randomly selected sample from 2% of classes since 1991. Results: 277 (8.1%) of the 3409 schoolchildren studied (including 575 non responders to this question) reported having had an experience with e-cigarette. Experimentation rate is 6.4% among the 12 - 14-year-old, 11.8% among the 15 - 16-year-old and 9% among the 17-year-old schoolchildren. Among the 12 - 14- year-old schoolchildren, 64.4% of e-cigarette experimentation was by non-smokers. Of the 17-year-old teenagers who had used e-cigarettes, 12.4% were non-smokers. For the whole population, 33.2% of those having tried e-cigarette are non-smoker, 22.7% occasional smoker, 3.6% ex-smoker and 40.4% daily smoker. Those who experiment cannabis, shisha or binge-drinking are more frequently users of e-cigarette. In the smoker group, there is an inverse trend of rela- tionship between the readiness to quit tobacco and the rate of use of e-cigarette. Conclusion: For teenager’s, e-cigare- ttes have become not a product to aid quit tobacco but a product for experimentation and initiation of cigarette use. Regulation is urgently needed to control the emergent use of this new tobacco product by children.

Establishing a predictive model for fast online determination of relative density and refractive index of e-cigarette liquids using near-infrared spectroscopy

Relative density and refractive index are two fundamental physical properties of e?cigarette liquids to indicate their uniformity and batch stability.These parameters are mainly determined by a density meter and refractometer respectively,which is tedious and the analysis results are not readily available for massive measurements.A rapid determination of the two parameters is important for quality inspection and control of cigarette liquids,and a lot efforts have been devoted to establishing a predictive model for these parameters.In this study,a novel near-infrared spectroscopy(NIR)combined with particle swarm optimization-support vector regression(PSO-SVR)algorithm was applied to build a prediction model.The experimental results showed that comparing with the traditional partial least squares regression(PLSR)model and the principal component regression(PCR)model,the PSO?SVR model had superior prediction performance.

E-Cigarette Vapor Decreases Cellular Proliferation through Nicotine-Dependent Mechanisms

Electronic cigarette (e-cigarette) use has risen as individuals look for healthier nicotine delivery systems than conventional cigarettes, but recent studies have demonstrated variable physiological responses to e-cigarette vapor. The safety of e-cigarette vapor remains an open question. We investigated the molecular cellular response of adenocarcinoma human alveolar basal epithelial (A549) cells to flavored e-cigarette vapor. E-cigarette and cigarette vapor were extracted via a vacuum-percolating system into PBS. The effects of a flavored e-liquid containing nicotine (eCSE) and nicotine free e-liquid (NFeCSE) were compared to cigarette smoke extract (CSE), pure nicotine, glycerol, and PBS. Cells exposed to eCSE and NFeCSE had decreased cell viability and proliferation. An increase in active caspase-3 was observed in cells exposed to NFeCSE, while cells exposed to eCSE and CSE displayed no change, suggesting nicotine-mediated protection from apoptosis. However, phosphorylated Akt, which regulates cellular proliferation, was elevated in response to eCSE, NFeCSE, CSE, and glycerol. As the glutathione-oxidative stress response was known to integrate cellular factors including carcinogenesis, inflammation, and cell proliferation, GSH/GSSG levels were measured in cells exposed to e-cigarette smoke. An increase in oxidative stress was observed in cells treated with CSE, but not eCSE, suggesting components in CSE independent of nicotine may be contributing to an imbalance in the stress response. These results indicate e-cigarette vapor affects A549 cell viability dependent on nicotine, and is distinct from CSE-induced mechanisms of oxidative-stress.

E-cigarettes in ten Southeast Asian countries:a comparison of national regulations

The market and popularity of e-cigarettes are growing rapidly worldwide.However,the research and regulation of this novel products have lagged behind.In this paper,we reviewed and compared the regulatory mechanisms regarding e-cigarettes among ten Association of Southeast Asian Nations(ASEAN)member states.Our findings demonstrated a continuum of the legal regulations of e-cigarettes in this region:on the one hand,countries such as Brunei,Cambodia,Thailand,and Singapore have prohibited the importation and sale of e-cigarettes with existing tobacco control laws or specific regulations;on the other,countries such as Myanmar and Vietnam had almost no legal restrictions on e-cigarettes whatsoever.This overview of national regulations not only clarified the legal status of e-cigarettes in the ASEAN region but also provided informing lessons for countries currently lacking e-cigarette regulations such as China.

Toxicology of Commonly Found Ingredients in E-Cigarettes: A Brief Review

Electronic cigarettes (EC) have gained popularity among smokers due to their taste, smell, appearance, and easy availability compared to traditional cigarettes, as well as the perception that they are safer than traditional cigarettes. These devices result in aerosols containing nicotine, propylene glycol, glycerin, ethylene glycol, vitamin E, and chemical flavors inhaled into the lungs. Other components found in these vapors include heavy metals such as nickel, chromium, lead, manganese, and tin. In addition, some ingredients volatilization leads to toxic aldehydes formation such as formaldehyde, acetaldehyde, and acrolein. Smoking cigarettes is addictive and has been associated with many health issues such as heart disease, lung cancer, etc. Rising awareness of these dangers moves more people towards these electronic delivery systems, reducing the health effects of cigarettes. The toxicity of EC’s ingredients is well studied when ingested;however, their toxicity through inhalation remains unclear. Consequently, the use of ECs has become a significant concern worldwide and raises whether it is indeed safe to use. This paper will serve as a literature review paper to discuss the toxicity of commonly found ingredients in ECs and their associated health issues. Our conclusion emphasizes that even though smoking EC is less risker than smoking traditional cigarettes, it is still not safe due to the potentially harmful effect these E-cig’s ingredients have on the human’s health. In addition, E-cigarette’s aerosol could also contain toxic compounds such as formaldehyde, acetaldehyde, and acrolein due to glycerin’s thermo-degradation.

E-Cigarette Survey among Student Pharmacists Reveals Troubling Results

The rise in “vaping”-associated deaths in the United States raises serious concerns. A justification for some level of risk is that e-cigarettes might provide a “reverse-gateway” from smoking traditional cigarettes to a less-harmful alternative. But are users actually smokers? We developed an electronic on-line survey to gather data regarding e-cigarette usage in a target study population of pharmacy students. The survey was created using Google Forms to collect the responses anonymously. We surveyed medical-savvy healthcare students about their e-cigarette use, and whether or not their healthcare providers were aware of their e-cigarette use. Although nearly one-fourth of a convenience sampling of 134 pharmacy-student respondents (23.9%) reported using e-cigarettes, only 2.0% reported prior regular cigarette use, 28% used cartridges containing nicotine and only 11.2% had tried and wanted to quit. The majority (64.1%) reported that their healthcare providers did not ask about such use, and respondents did not volunteer this information. The results of this pilot survey reveal a significant e-cigarette use among health-aware pharmacy students, and they do not support the notion that the respondents do so to quit smoking. The observation that most of the students’ healthcare providers did not inquire about their e-cigarette use, coupled with the finding that users did not volunteer their vaping behavior, suggests that the information should be included when getting a medical history. Further research is needed to determine what behavioral factors may play a role in this type of decision-making among student healthcare professionals.

Does Smoking Weaken the Immune System: A Narrative Review

Smoking has a complex impact on the immune system, affecting both innate and adaptive immunity. It can exacerbate pathogenic immune responses and attenuate defensive immunity, leading to a higher susceptibility to infections and certain diseases. The chemicals in cigarette smoke, such as nicotine and carbon monoxide, can alter immune cell functions and inflammatory responses. Smoking can also have long-term effects on the immune system, with some changes persisting even after quitting [1]. According to a Penn Medicine Physician, the Medical Oncologist Dr. David Porter, “People who are smokers tend to get sicker from infections”, “It may be that smoking impacts the immune system’s ability to respond appropriately”. Thus, such individuals within smoking exposure history might be considered as immunocompromised due to the altered and weakened immune system. Cigarette smoking is a prevalent habit with far-reaching health implications. Among its many adverse effects, smoking significantly alters the immune system’s functionality [1].

Immediate Respiratory Response to Electronic Cigarette Use

Background: Electronic cigarettes were originally designed to reduce adult dependency on normal cigarettes and as a tobacco cessation tool to substitute traditional cigarettes. But it has become the most popular among teenagers. Rationale: To investigate the immediate adverse respiratory effect of short-term electronic cigarette vapor inhalation. Method: Twenty-five subjects were randomly selected and used in this study. The respiratory resistance values were evaluated and used for comparison. The subjects were asked to breathe into the Airflow Perturbation Device (APD) for evaluation of their respiratory resistance before vaping (in triplicate). The same subjects, a minute later, were then asked to use one poke (3 seconds) of the e-Cigarette device to inhale e-Cigarette vapor with nicotine from a pod with 59 mg/ml nicotine. Immediately following the e-Cigarette use, their respiratory resistance was measured again (in triplicate). Results: Comparing the respiratory resistance values before and immediately after exposure to e-Cigarette vapor showed that their respiratory resistance increased almost immediately. Conclusion: Although there are long-term studies showing that the e-Cigarette is as harmful as regular cigarettes, this study showed a nearly immediate effect of using the e-Cigarette that significantly increased the respiratory resistance of the user. Very short exposure time to e-Cigarette vapor (3 seconds only), caused an immediate adverse physiologic effect in respiratory resistance.

Smoking and Passive Smoking

Objective:To review the literature on associations between cardiovascular diseases and tobacco use,including recent trends in smoking behaviors and clinical approaches for cessation of smoking.Methods:A literature review of recent scientifi c fi ndings for smoking and cardiovascular diseases and recommendations for obtaining cessation.Results:Tobacco smoking is causally related to cardiovascular disease,with nearly a half million deaths annually attributed to cigarette smoking in the United States.The human,economic,medical,and indirect costs are enormous.Secondhand smoke as inhaled from the environment also plays an important role in the genesis of cardiovascular diseases.A recent trend in the use of e-cigarettes is noted particularly among youth.For children,prevention is the best strategy.For adult smokers,behavioral treatments,self-help approaches,and pharmacologic therapies are readily available.Clinicians can have a signifi cant impact on patients’smoking habits.Adding to individual strategies,regulatory community and public health approaches provide the potential for eliminating the use of tobacco.Conclusion:Tobacco smoke causes cardiovascular morbidity and death.Clinicians can play a role in preventing smoking and promoting cessation.

Misclassification of smoking habits:An updated review of the literature

BACKGROUND Misclassification of smoking habits leads to underestimation of true relationships between diseases and active smoking, and overestimation of true relationships with passive smoking. Information on misclassification rates can be obtained from studies using cotinine as a marker.AIM To estimate overall misclassification rates based on a review and meta-analysis of the available evidence, and to investigate how misclassification rates depend on other factors.METHODS We searched for studies using cotinine as a marker which involved at least 200 participants and which provided information on high cotinine levels in selfreported non-, never, or ex-smokers or on low levels in self-reported smokers. We estimated overall misclassification rates weighted on sample size and investigated heterogeneity by various study characteristics. Misclassification rates were calculated for two cotinine cut points to distinguish smokers and nonsmokers, the higher cut point intended to distinguish regular smoking.RESULTS After avoiding double counting, 226 reports provided 294 results from 205 studies. A total of 115 results were from North America, 128 from Europe, 25 from Asia and 26 from other countries. A study on 6.2 million life insurance applicants was considered separately. Based on the lower cut point, true current smokers represented 4.96%(95% CI 4.32-5.60%) of reported non-smokers, 3.00%(2.45-3.54%) of reported never smokers, and 10.92%(9.23-12.61%) of reported exsmokers. As percentages of true current smokers, non-, never and ex-smokers formed, respectively, 14.50%(12.36-16.65%), 5.70%(3.20-8.20%), and 8.93%(6.57-11.29%). Reported current smokers represented 3.65%(2.84-4.45%) of true non-smokers. There was considerable heterogeneity between misclassification rates.Rates of claiming never smoking were very high in Asian women smokers, the individual studies reporting rates of 12.5%, 22.4%, 33.3%, 54.2% and 66.3%. False claims of quitting were relatively high in pregnant women, in diseased individuals who may recently have been advised to quit, and in studies considering cigarette smoking rather than any smoking. False claims of smoking were higher in younger populations. Misclassification rates were higher in more recently published studies. There was no clear evidence that rates varied by the body fluid used for the cotinine analysis, the assay method used, or whether the respondent was aware their statements would be validated by cotinine-though here many studies did not provide relevant information. There was only limited evidence that rates were lower in studies classified as being of good quality,based on the extent to which other sources of nicotine were accounted for.CONCLUSION It is important for epidemiologists to consider the possibility of bias due to misclassification of smoking habits, especially in circumstances where rates are likely to be high. The evidence of higher rates in more recent studies suggests that the extent of misclassification bias in studies relating passive smoking to smoking-related disease may have been underestimated.

Bilateral Pneumonia and Pleural Effusions Subsequent to Electronic Cigarette Use

Electronic nicotine delivery systems also known as electronic cigarettes (or e-cigarettes) are marketed by their manufactures as a safer alternative to tobacco cigarettes because of potentially reduced delivery of toxins. However, the scientific evidence and the long-term health effects of e-cigarettes are limited. We describe a case of a 43-year-old man who had been smoking electronic cigarettes excessively for three days and presented with acute dyspnea, increased work of breathing and tachycardia. Subsequent chest x-ray revealed bilateral pleural effusions. In addition, the patient had a new oxygen requirement and was thus admitted with a diagnosis of pneumonia and bilateral pleural effusions. The case and the potential harmful effects of electronic cigarettes are discussed herein.

Investigation on the Danger of Electronic Cigarette on Young Adults

It is commonly known that smoking tobacco can lead to adverse health consequences.However,faced with the temptation of tobacco,there are still many tobacco users who choose to ignore the health effect of smoking.Recently,electronic cigarettes(E-cigarettes)have been introduced as a way to remedy the negative consequences of smoking tobacco.E-cigarettes have become a trend,especially among youth populations,given their curiosity about the new product,their pursuit of tobacco culture,and their misconceptions about e-cigarettes’harmful effects.This has caused the number of e-cigarette users to continue rising.However,studies have shown that smoking e-cigarettes can have a harmful effect on their users,and particularly for young smokers,with harmful effects deteriorating not only the physical health of the smoker but also mental and behavioral health.This paper focuses on an investigation into harmful effects that e-cigarettes have on youth,exploring the specific hazards of the chemicals in e-cigarettes.The hope is that this work can offer beneficial insights for youth and the society as a whole concerning the harmful effects of e-cigarettes,thereby reducing or terminating the use of e-cigarettes altogether.

Arsenic species in electronic cigarettes:Determination and potential health risk

Human exposure to contaminants from electronic cigarettes(e-cigarettes)and the associated health effects are poorly understood.There has been no report on the speciation of arsenic in e-liquid(solution used for e-cigarettes)and aerosols.We report here determination of arsenic species in e-liquids and aerosols generated from vaping the e-liquid.Seventeen e-liquid samples of major brands,purchased from local and online stores in Canada and China,were analyzed for arsenic species using high-performance liquid chromatography and inductively coupled plasma mass spectrometry.Aerosols condensed from vaping the eliquids were also analyzed and compared for arsenic species.Six arsenic species were detected,including inorganic arsenate(iAsⅤ),arsenite(iAsⅢ),monomethylarsonic acid(MMA),and three new arsenic species not reported previously.In e-liquids,iAsⅢwas detected in 59%,iAsⅤin 94%,and MMA in 47%of the samples.In the condensate of aerosols from vaping the e-liquids,iAsⅢwas detected in 100%,iAsv in 88%,and MMA in 13%of the samples.Inorganic arsenic species were predominant in e-liquids and aerosols of e-cigarettes.The concentration of iAsⅢin the condensate of aerosols(median 3.27μg/kg)was significantly higher than that in the e-liquid(median 1.08μg/kg)samples.The concentration of inorganic arsenic in the vaping air was approximately 3.4μg/m3,which approaches to the permissible exposure limit(10μg/m3)set by the United States Occupational Safety and Health Administration(OSHA).According to the Environmental Protection Agency’s unit risk factor(4.3×10-3 perμg/m3)for inhalation exposure to inorganic arsenic in the air,the estimated excess lung cancer risk from lifetime exposure to inorganic arsenic in the ecigarette vaping air(3.4μg/m3),assuming e-cigarette vaping at 1%of the time,is as high as1.5×10-4.These results raise health concerns over the exposure to arsenic from electronic cigarettes.

Burns resulting from spontaneous combustion of electronic cigarettes: a case series

Background:Electronic cigarette(e-cigarette)sales have grown rapidly in recent years,coinciding with a public perception that they are a safer alternative to traditional cigarettes.However,there have been numerous media reports of fires associated with e-cigarette spontaneous combustion.Case Presentation:Three severe burns caused by spontaneous combustion of e-cigarettes within a 6-month period were treated at the Santa Clara Valley Medical Center Burn Unit.Patients sustained partial and full-thickness burns.Two required hospitalization and surgical treatment.Conclusions:E-cigarettes are dangerous devices and have the potential to cause significant burns.Consumers and the general public should be made aware of these life-threatening devices.