Smoke Toxicity Research Articles

Construction of graphite oxide modified black phosphorus through covalent linkage: An efficient strategy for smoke toxicity and fire hazard suppression of epoxy resin

The black phosphorus (BP) can be compounded with other two-dimensional materials with flame retardant effect to achieve better synergistic effect. Herein, the multifunctional BP-RGO nanohybrids was fabricated by solvothermal strategy to improve the dispersion state of BP in epoxy resin (EP) and enhance its fire safety performance, where the reduced graphene oxide (RGO) was attached on the surface of BP via PC and POC bonds. With the incorporation of 2.0 wt% BP-RGO into EP matrix, 54.4 % reduction in total heat release (THR) was achieved along with 55.2 % decrease in peak heat release rate (PHRR) compared with neat EP. As a similar trend, the toxic CO and aromatic compounds were significantly inhibited, and the maximum decrease (28.5 %) in total smoke production (TSP) was achieved, indicating the enhanced fire safety performance of EP nanocomposites. These positive results is attributed to the synergistic effect of physical nano-barrier, free radicals trapping and char formation between BP and RGO components. Meanwhile, the EP/BP-RGO2.0 nanocomposites exhibited satisfying air stability even after being immersed in water for a month. This work enriches the strategies for enhancing the air stability of BP, and confirms its potential for smoke toxicity and fire hazard suppression in polymer nanocomposites.

Hookah venue employees’ knowledge and perceptions of hookah tobacco smoking

BackgroundRecent years showed sharp proliferation of hookah bars worldwide with scarcity of workplace safety regulations. Hookah server employees are at high risk for elevated harm. This study reported hookah smoke...

Integration of Time and Spatially Resolved In-Situ Temperature and Pressure Measurements With Soft Ionisation Mass Spectrometry Inside Burning Superslim and King-Size Cigarettes

Summary Background Combustion as well as pyrolysis of tobacco greatly affect the type and levels of toxicants in cigarette smoke. We previously developed an approach to combine simultaneous temperature and pressure measurements with fast in-situ microprobe chemical sampling inside a burning cigarette, producing a series of temperature and gas-flow velocity maps that characterize this dynamic system in response to externally applied air flow. Aim Two cigarette types differing only in diameter were puffed under ISO 3308 and Health Canada Intense (HCI) regimes to further understand the dynamic interaction of air flow and cigarette design parameters on tobacco combustion and pyrolysis by applying the thermophysical and thermo-chemical mapping approach. Methods Three types of sampling probes were inserted, which are thermocouple arrays for gas-phase temperature, quartz tubes for pressure measurement, and a heated sampling microprobe coupled to a single-photon soft ionisation mass spectrometer for chemical analysis. Two kinds of similarly constructed cigarettes with the same blend were analysed: superslim (17 mm circumference) and king-size (24 mm circumference). Synchronization among the sampled signals was achieved by mapping two probes (e.g., temperature/chemistry or temperature/pressure) at a time. The physical and chemical events were visualised and compared between the cigarettes and puffing regimes. Results A series of temperature, pressure, and chemical maps were obtained for the superslim and king-size cigarettes under ISO and HCI conditions. The pressure in the burning cigarette was higher in the superslim cigarette, and the temperature distribution differed between the two cigarette formats. As expected, temperatures and pressures were higher under HCI puffing than under ISO puffing for both cigarette formats. Thermochemical maps for e.g., benzene and nitric oxide formation were qualitatively similar between the superslim and king-size cigarettes. For other substances the distribution was markedly different. Conclusion The application of multi-probe in-situ chemical sampling is suitable to analyse highly dynamic combustion and pyrolysis processes occurring inside the two types of cigarettes. Ultimately, a direct comparison of cigarette circumferences on the complex combustion processes and formation of smoke constituents was achieved. [Beitr. Tabakforsch. Int. 29 (2020) 44–54]

Obesity as a Source of Endogenous Compounds Associated With Chronic Disease: A Review.

In 2014, it was estimated that more than 1.9 billion adults were overweight with over 600 million classifiable as obese. Approximately two-thirds of U.S. adults over 20 years of age are currently overweight with about 35% classified as obese, a figure thought likely to reach 42% by 2030 in those over 18 years of age. Adipose cells from stored body fat secrete estrogen and a very large number (> 500) of biologically active substances termed adipokines, in addition to inducing, by other cell-driven effects, pathological alterations in insulin pathways. The U.S. National Cancer Institute reports that exposure to the hormone disrupting and proinflammatory effects of excess adipose tissue are associated with an increased risk for 11 different cancers. Obesity is also associated with a number of serious non-neoplastic conditions including metabolic syndrome and type 2 diabetes; menstrual cycle irregularities and lowered fertility (men and women); and abnormal bone morphology in a subset of female patients. In men hypogonadism, low testosterone levels, benign prostatic hyperplasia, and lowered sperm counts have been reported. In developed countries, the endogenous adverse health burden associated with obesity is only matched, quantitatively and qualitatively, by the exogenous toxicity of cigarette smoking. The investigation of possible hormonal and/or proinflammatory effects of chemicals should include an assessment of the profound endocrine alterations associated with obesity.

Fire hazard of textile materials based on polyester fibers for rail vehicles

Introduction. Wide application for the arrangement of passenger railcars (curtains, upholstery and covers of chairs and sofas, bedding) is occupied by fabrics made of fire-proof, chemically modified polyester fibers that meet ­foreign requirements. An experimental study of the parameters of fire hazard of such a fire-resistant textiles ac­cording to the Russian requirements to furnish railcars showed the impossibility of achieving normative criteria on the toxicity of combustion products and smoke-forming ability because of the peculiarities of the process of ­thermal decomposition. Therefore, an important task is to conduct a comprehensive research on the feasibility of establishing realistic numerical values of criteria of toxicity of products of combustion and smoke generation. Problem of the issue . A feature of the thermal decomposition of polyethylene terephthalate (PET) is its ability to be in a viscous state at high temperatures. The most effective method of fire protection of PET fibers is chemical modification at the stage of their production due to the introduction of organophosphorus functional compounds in the synthesis process. Wide application in the construction of railcars, flameproof tissue is significantly hampered by their failure to comply with the requirements for smoke generation ability and toxicity index of combustion ­products. Results and discussion . Introduction in the polymer chain of PET retardants that do not affect the conditions of tech­nological processing, possibly with their contents not more than 10 % by mass. This amount of flame re­tardant provides the material’s resistance to ignition and flame spread on the surface, lack of education burning melt, but does not alter significantly the toxicity index of combustion products and the rate of smoke generation. Experimental data on the toxicity of combustion products (the yield of CO and CO 2 in the mode of flaming combus­tion) flame retardant, low flame on the surface of the fabrics, flameproof polyester fibres. A comparison of the results of determination of toxicity index of products of combustion to the results of calculations of the generalized index of toxicity (CIT g ). Conclusions . The criterion value of CIT g (0.75) was established for evaluating the possibility of using textile materi als in railway sleeping railcars, corresponding to the index of toxicity of combustion products from 34 to 52 mg/m 3 (43 mg/m 3 ± 20 %), which indicates the possibility of using fabrics with the index of toxicity of combustion products HCl 50 ≥ 35 mg/m 3 . Proposals have been developed to improve fire safety requirements for textile materials used in passenger railcars.

Assessment of Efficiency of Eco-Friendly Organic Mosquito Repellent Developed using Elephant Dung

Mosquitoes transmit a range of infectious agents that affects human health. Malaria, dengue fever, yellow fever and other mosquito-borne diseases infect countless individuals and account for thousands of deaths annually, causing a large burden to public health and on the economic process of developing countries. At present, concerning 40% of the world’s populations mainly in India live in areas where the chance of dengue fever transmission is most. High rate of reproduction and lack of effective vaccines against several mosquito-borne pathogens makes us extremely addicted to the utilization of insecticides to manage the mosquito populations so as to prevent illness due to transmission. Mosquito repellents mainly consist of pyrethroids that lead to hyper excitation of nervous systems and its prolong usage results in corneal damage, liver damage and asthma. Hence, need for the development of the most effective organic herbal insect repellent must be taken into account due to the toxicity issues, together with the increased incidence of resistance to insects. In this perspective, the present study aimed to develop an eco-friendly mosquito repellent as an alternative for chemical repellent using elephant dung and other natural resources and to assess the efficiency of the organic repellant compared to commercial repellent. Elephant dung has being employed for fuel supply, biofertilizer and paper production. Natural ingredients like Nerium flowers, Tulsi, Neem leaves, Lemon grass oil and Natural loban were used in combination with the elephant dung to reinforce the potency of the mosquito repellent. Smoke toxicity of organic mosquito repellent was evaluated. Emission test for commercial and developed repellent was also compared and it is evident that there is 57% reduction in the carbon-di-oxide emission from developed repellent than commercial repellent and there are no traces of emission of carbon monoxide from the developed repellent. Also, cage test proves that the developed mosquito repellent is highly efficient against mosquitoes and hence can be more effectively used for control of mosquitoes.

Effects of Very Low Nicotine Content Cigarettes on Smoking Behavior and Biomarkers of Exposure in Menthol and Non-menthol Smokers.

IntroductionBecause 30% of cigarettes sold in the United States are characterized as menthol cigarettes, it is important to understand how menthol preference may affect the impact of a nicotine reduction policy.MethodsIn a recent trial, non-treatment-seeking smokers were randomly assigned to receive very low nicotine cigarettes (VLNC; 0.4 mg nicotine/g tobacco) or normal nicotine cigarettes (NNC; 15.5 mg/g) for 20 weeks. On the basis of preference, participants received menthol or non-menthol cigarettes. We conducted multivariable regression analyses to examine whether menthol preference moderated the effects of nicotine content on cigarettes per day (CPD), breath carbon monoxide (CO), urinary total nicotine equivalents (TNE), urinary 2-cyanoethylmercapturic acid (CEMA), and abstinence.ResultsAt baseline, menthol smokers (n = 346) reported smoking fewer CPD (14.9 vs. 19.2) and had lower TNE (52.8 vs. 71.6 nmol/mg) and CO (17.7 vs. 20.5 ppm) levels than non-menthol smokers (n = 406; ps < .05). At week 20, significant interactions indicated that menthol smokers had smaller treatment effects than non-menthol smokers for CPD (–6.4 vs. –9.3), TNE (ratio of geometric means, 0.22 vs. 0.10) and CEMA (ratio, 0.56 vs. 0.37; ps < .05), and trended toward a smaller treatment effect for CO (–4.5 vs. –7.3 ppm; p = .06). Odds ratios for abstinence at week 20 were 1.88 (95% confidence interval [CI] = 0.8 to 4.4) for menthol and 9.11 (95% CI = 3.3 to 25.2) for non-menthol VLNC smokers (p = .02) relative to the NNC condition.ConclusionsAlthough menthol smokers experienced reductions in smoking, toxicant exposure, and increases in quitting when using VLNC cigarettes, the magnitude of change was smaller than that observed for non-menthol smokers.ImplicationsResults of this analysis suggest that smokers of menthol cigarettes may respond to a nicotine reduction policy with smaller reductions in smoking rates and toxicant exposure than would smokers of non-menthol cigarettes.

Synergistic Effect of Mesoporous Nanocomposites with Different Pore Sizes and Structures on Fire Safety and Smoke Suppression of Epoxy Resin

AbstractEpoxy resin (EP) is extremely flammable, and smoke release during combusting is considered toxic and harmful for human health. Mesoporous materials offer reliable desorption performance due to their large specific surface area. Therefore, the construction of mesoporous nanocomposites is a novel method for enhanced smoke suppression effect of EP. In this work, zinc hydroxystannate (ZHS)‐mesoporous silica (SBA‐15 and MCM‐41) modified reduced graphene oxide (RGO) is successfully prepared and used to enhance the fire safety of EP. SBA‐15‐RGO‐ZHS/EP exhibits the lowest total smoke production (22.8 m2) and peak heat release rate (416 kW m−2), which are reduced by 55% and 37% compared with pure EP, respectively. Furthermore, the effect of mesoporous nanoparticles is also investigated. Apparently, the smoke suppression effect and flame retardancy of SBA‐15‐RGO‐ZHS/EP is even more remarkable than that of MCM‐41‐RGO‐ZHS/EP, which indicates that the pore size and structure of mesoporous are important factors for reducing the smoke toxicity of EP. Finally, it is verified that its enhanced fire safety is attributed to the synergistic action of physical barrier properties of RGO, “labyrinth” effect of SBA‐15, and catalytic ability of ZHS.

Evaluation of an online, real-time, soft-photon ionisation time-of-flight mass spectrometer for mainstream tobacco smoke analysis

Mainstream tobacco smoke is a complex and dynamic aerosol, consisting of particulate and vapour phases. Most approaches to determine mainstream smoke toxicant yields are based on offline techniques that limit the opportunity to observe in real time the processes leading to smoke formation. The recent development of online real-time analytical methods offers many advantages over traditional techniques. Here we report the LM2X-TOFMS (Borgwaldt GmbH, Germany), a commercial instrument that couples a linear smoking engine with a time-of-flight mass spectrometer for real-time per-puff measurement of the vapour phase of mainstream cigarette smoke. Total cigarette and puff-by-puff (μg/puff) yields were evaluated, in line with International Council of Harmonisation recommendations, for seven smoke toxicants: acetaldehyde, acetone, 1,3-butadiene, 2-butanone, benzene, isoprene and toluene. Measurements were unaffected by small system changes including replacing the sampling capillary or time of day (all P > 0.05), indicating that the LM2X-TOFMS is rugged. Control charts showed that the system has good stability and control. Analysis of certified gas mixtures of six concentrations of each analyte showed a highly linear response for all seven analytes (R2 = 0.9922–0.9999). In terms of repeatability, the lowest variation was observed for isoprene with a coefficient of variation (CV) of < 6% for each concentration. Acetaldehyde showed the highest CV, increasing from 8.0 to 26.6% with decreasing gas concentration. Accuracy was analysed in terms of relative error, which was ± 16% for six of the analytes; however, the relative error for acetaldehyde was (− 36.2%), probably due to its low ionisation efficiency under the instrument’s vacuum ultraviolet lamp. Three cigarette products (reference and commercial) with different ISO tar levels were analysed by the LM2X-TOFMS puff by puff under ISO regulatory smoking conditions. The relative standard deviation based on average yield per cigarette for each analyte in each product (summed puffs per product, n = 30) ranged from ≤ 9.3 to ≤ 16.2%. Measurements were consistent with published data per cigarette. In conclusion, the LM2X-TOFMS is suitable for determining the vapour-phase yields of seven analytes on a real-time, puff-by-puff basis, and can be utilised for both fast screening (qualitative) and quantitative measurements of mainstream cigarette smoke.

Toxicants in cigarette smoke adsorbed on red phosphorene nanosheet: A first-principles insight

Initially, the geometric and electronic features of red phosphorene nanosheet (P-NS) are examined using the SIESTA package. The energy gap, density of states (DOS) spectrum, and electron density are estimated for the isolated red P-NS, and toxic cigarette vapors acrolein, acrylamide, and nicotine adsorbed red P-NS. In addition, the surface assimilating attributes like Bader charge transfer, energy gap variation, and adsorption energy is computed for the toxic cigarette vapors adsorbed red P-NS. The modification of these significant parameters upon the surface assimilation of the toxic cigarette vapors on red P-NS is clearly scrutinized in atomic levels in order to enunciate the chemo-sensing behavior of red P-NS towards the toxic cigarette vapors like acrolein, acrylamide, and nicotine (which are widely released into the atmosphere through tobacco smoke and cigarette).

Aldehyde and Volatile Organic Compound Yields in Commercial Cigarette Mainstream Smoke Are Mutually Related and Depend on the Sugar and Humectant Content in Tobacco.

IntroductionThe World Health Organization (WHO) Framework Convention on Tobacco control recognizes the need for tobacco product regulation. In line with that, the WHO Study Group on Tobacco Product Regulation (TobReg) proposed to regulate nine toxicants in mainstream cigarette smoke, including aldehydes, volatile organic compounds (VOCs), and carbon monoxide (CO). We analyzed their relations in 50 commercially available cigarette brands, using two different smoking regimes, and their dependence on sugar and humectant concentrations in tobacco filler.MethodsWe measured sugar and humectant in tobacco filler and aldehydes, VOCs, and tar, nicotine, and CO (TNCO) in mainstream smoke. The general statistics, correlations between emission yields, and correlations between contents and emissions yields were determined for these data.ResultsFor aldehydes, several significant correlations were found with precursor ingredients in unburnt tobacco when smoked with the Intense regime, most prominently for formaldehyde with sucrose, glucose, total sugars, and glycerol. For VOCs, 2,5-dimethylfuran significantly correlates with several sugars under both International Standards Organization (ISO) and Intense smoking conditions. A correlation network visualization shows connectivity between a sugar cluster, an ISO cluster, and an Intense cluster, with Intense formaldehyde as a central highest connected hub.ConclusionsOur multivariate analysis showed several strong connections between the compounds determined. The toxicants proposed by WHO, in particular, formaldehyde, can be used to monitor yields of other toxicants under Intense conditions. Emissions of formaldehyde, acetaldehyde, acrolein, and 2,5-dimethylfuran may decrease when sugar and humectants contents are lowered in tobacco filler.ImplicationsOur findings suggest that the aldehydes and VOCs proposed by TobReg are a representative selection for smoke component market monitoring purposes. In particular, formaldehyde yields may be useful to monitor emissions of other toxicants under Intense conditions. Since the most and strongest correlations were observed with the Intense regime, policymakers are advised to prescribe this regime for regulatory purposes. Policymakers should also consider sugars and humectants contents as targets for future tobacco product regulations, with the additional advantage that consumer acceptance of cigarette smoke is proportional to their concentrations in the tobacco blend.

Cigarette smoke inhalation aggravates diabetic kidney injury in rats.

Diabetic kidney disease (DKD) is the leading cause of end-stage kidney disease. Epidemiological studies have demonstrated that cigarette smoke or nicotine is a risk factor for the progression of chronic kidney injury. The present study analyzed the kidney toxicity of cigarette smoke in experimental rats with DKD. Experimental diabetes was induced in 7-week-old Sprague-Dawley rats by a single intraperitoneal injection of streptozotocin (60 mg kg-1). Four weeks after the induction of diabetes, rats were exposed to cigarette smoke (200 μg L-1), 4 h daily, and 5 days per week for 4 weeks. Cigarette smoke did not affect the levels of plasma glucose, hemoglobin A1c, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol or non-esterified fatty acids in both control and diabetic rats under the experimental conditions. Cigarette smoke, however, significantly increased diabetes-induced glomerular hypertrophy and urinary kidney injury molecule-1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL) excretion, suggesting exacerbation of diabetic kidney injury. Cigarette smoke promoted macrophage infiltration and fibrosis in the diabetic kidney. As expected, cigarette smoke increased oxidative stress in both control and diabetic rats. These data demonstrated that four weeks of exposure to cigarette smoke aggravated the progression of DKD in rats.

Toxicity analysis of second use lithium-ion battery separator and electrolyte

Pyrolysis gas chromatography-mass spectrometry (Py-GC-MS) test, smoke toxicity analysis and mouse biological toxicity test were carried out on the second use lithium-ion battery separator and electrolyte. It was found that the types of cracked products of separator and electrolyte under different state of health (SOH) were basically the same, mainly phosphoryl fluoride (POF3) and long-chain F-containing alkanes, alcohols and esters. The content of POF3 in the cracked product increases as the SOH increases. The toxic gas components released after the separator and the electrolyte are completely burned mainly include CO, CO2, and HF. The HF content decreased as the battery SOH decreased, from 101.6 mg/g of the 100% SOH battery to 44.1 mg/g of the 65% SOH battery. In the biological toxicity test, all the mice were found to stop running, close eyes, shed tears, and have shortness of breath. After the test, only 65% SOH and 100% SOH mice recovered their body weight to the pre-experimental average state and gained weight.

Facile synthesis of aluminum branched oligo(phenylphosphonate) submicro-particles with enhanced flame retardance and smoke toxicity suppression for epoxy resin composites

A novel and submicro-scale aluminum branched oligo(phenylphosphonate) (AHPP) has been successfully synthesized and embedded into a polymeric substrate to improve the fire safety of epoxy resin (EP). The chemical structures of intermediates and target products were characterized using the nuclear magnetic resonance spectroscopy, X-ray diffraction and Fourier transform infrared analysis. Morphology analysis confirmed that all of the as-synthesized AHPP submicro-particles are mutually well-separated. Combustion results demonstrated that the limiting oxygen index value is increased to 30.5% from 23.5% while the PHRR and THR are decreased by ca. 68.1% and 41.2%, respectively for the EP/AHPP-7.5 composite compared to the corresponding values for pure EP. In addition, the binary blends display the satisfying smoke toxicity suppression performance during combustion. The total smoke production and the total CO yield for EP/AHPP-7.5 are dramatically reduced by 62.0% and 32.3%, respectively, which may mainly be ascribed to the catalytic carbonization performance of the polymers and formation of Al2O3 layers on the surface of the char residues. As a result, the findings in this study enabled the submicro-scale phosphorus-containing flame retardant to be a potential candidate as an efficient additive for reducing smoke toxicity of polymer composites.

Waterpipe tobacco smoke toxicity: the impact of waterpipe size

IntroductionWaterpipe tobacco smoking continues to show increasing popularity, especially among individuals between 18 and 22 years old. Waterpipe tobacco smoke (WTS) is a mixture of particulates and gases formed from...

Combination of black phosphorus nanosheets and MCNTs via phosphorus[sbnd]carbon bonds for reducing the flammability of air stable epoxy resin nanocomposites

As a rising star of two-dimensional material, black phosphorus (BP) has attracted tremendous attention in applications of photovoltaics, transistors and batteries due to its unique characteristics. Inspiring, we developed a simple strategy to fabricate BP-MCNTs as highly promising inorganic phosphorus-based flame retardant. After incorporation 2 wt% BP-MCNTs11(the mass ratio of BP:MCNTs=1:1) nanohybrid, the peak of heat release rate and total heat release of EP nanocomposites reduced by 55.81% and 41.17% at a phosphorus content of only 1 wt%, and the comprehensive index FGI for evaluating the flame retardant of materials decreased from 17.35 to 6.97. In addition, the typical flammable volatile are suppressed significantly, and the first stage of carbon monoxide release is disappeared. The improvement of fire safety and inhibition of smoke toxicity could be attributed to the the synergistic effects of nano-barrier, catalytic charring and radicals trapping of BP-MCNTs nanohybrid. More importantly, BP hybrid with MCNTs and wrapped in EP matrix which formed effective isolation protection against the ambient degradation. Raman spectra and SEM results confirmed that EP/BP-MCNTs performed enhanced ambient stability than EP/BP-BS nanocomposites after three months. This study demonstrates its great potential for preparation of air-stable BP based nanocomposites with enhanced fire safety.

The influence of highly dispersed Cu2O-anchored MoS2 hybrids on reducing smoke toxicity and fire hazards for rigid polyurethane foam

The extensive utilization of rigid polyurethane foam (RPUF) as construction insulation material has brought two main troubles to our society: fire risks and toxic hazards. To reduce the fire hazards of RPUF, a layered MoS2 decorated with Cu2O nanoparticles was creativity obtained by hydrothermal technology and facile wet chemical treatment for reducing the toxic product formations of polyurethane nanocomposites during combustion. Due to the low weight ratio of Cu2O attached onto MoS2, the resulting Cu2O-MoS2 hybrid effectively prevented the MoS2 nanosheets from restacking. However, the Cu2O-MoS2-M hybrid was produced by increasing content of Cu2O, which has the characteristic stacked layer structure of MoS2. Reduced harmful organic volatiles and the toxic gases (e.g. a respective decrease of ca. 28% and 53% for CO and NOx products) were obtained because of synergistic effect between the physical adsorption of MoS2 and catalysis action of Cu2O. Notably, the addition of Cu2O-MoS2 hybrids led to high char formation of the RPUF nanocomposite, indicating the effectively catalytic carbonization property. In addition, the N-Gas model for predicting fire smoke toxicity was developed and demonstrated. Furthermore, the research offers direct proofs of the negative influence of the stacked MoS2 on reducing the smoke toxicity for RPUF nanocomposites.

Vaporized E-Cigarette Liquids Induce Ion Transport Dysfunction in Airway Epithelia.

Cigarette smoking is associated with chronic obstructive pulmonary disease and chronic bronchitis. Acquired ion transport abnormalities, including cystic fibrosis transmembrane conductance regulator (CFTR) dysfunction, caused by cigarette smoking have been proposed as potential mechanisms for mucus obstruction in chronic bronchitis. Although e-cigarette use is popular and perceived to be safe, whether it harms the airways via mechanisms altering ion transport remains unclear. In the present study, we sought to determine if e-cigarette vapor, like cigarette smoke, has the potential to induce acquired CFTR dysfunction, and to what degree. Electrophysiological methods demonstrated reduced chloride transport caused by vaporized e-cigarette liquid or vegetable glycerin at various exposures (30 min, 57.2% and 14.4% respectively, vs. control; P < 0.0001), but not by unvaporized liquid (60 min, 17.6% vs. untreated), indicating that thermal degradation of these products is required to induce the observed defects. We also observed reduced ATP-dependent responses (-10.8 ± 3.0 vs. -18.8 ± 5.1 μA/cm2 control) and epithelial sodium channel activity (95.8% reduction) in primary human bronchial epithelial cells after 5 minutes, suggesting that exposures dramatically inhibit epithelial ion transport beyond CFTR, even without diminished transepithelial resistance or cytotoxicity. Vaporizing e-cigarette liquid produced reactive aldehydes, including acrolein (shown to induce acquired CFTR dysfunction), as quantified by mass spectrometry, demonstrating that respiratory toxicants in cigarette smoke can also be found in e-cigarette vapor (30 min air, 224.5 ± 15.99; unvaporized liquid, 284.8 ± 35.03; vapor, 54,468 ± 3,908 ng/ml; P < 0.0001). E-cigarettes can induce ion channel dysfunction in airway epithelial cells, partly through acrolein production. These findings indicate a heretofore unknown toxicity of e-cigarette use known to be associated with chronic bronchitis onset and progression, as well as with chronic obstructive pulmonary disease severity.

Smoking and pregnancy: Epigenetics and developmental origins of the metabolic syndrome.

Maternal smoking causes lower birth weight, birth defects, and other adverse pregnancy outcomes. Epidemiological evidence over the past four decades has grown stronger and the adverse outcomes attributed to maternal smoking and secondhand smoke exposure have expanded. This review presents findings of latent and persistent metabolic effects in offspring of smoking mothers like those observed in studies of maternal undernutrition during pregnancy. The phenotype of offspring of smoking mothers is like that associated with maternal undernutrition. Born smaller than offspring of nonsmokers, these children have increased risk of being overweight or obese later. Plausible mechanisms include in utero hypoxia, nicotine-induced reductions in uteroplacental blood flow, placental toxicity, or toxic growth restriction from the many toxicants in tobacco smoke. Studies have reported increased risk of insulin resistance, type 2 diabetes and hypertension although the evidence here is weaker than for overweight/obesity. Altered DNA methylation has been consistently documented in smoking mothers' offspring, and these epigenetic alterations are extensive and postnatally durable. A causal link between altered DNA methylation and the phenotypic changes observed in offspring remains to be firmly established, yet the association is strong, and mediation analyses suggest a causal link. Studies examining expression patterns of affected genes during childhood development and associated health outcomes should be instructive in this regard. The adverse effects of exposure to tobacco smoke during pregnancy now clearly include permanent metabolic derangements in offspring that can adversely affect life-long health.

Nicotine replacement therapy: A smoking cessation aid… an overview

Cigarette smoking is one of the most important causes of illness and premature death. The tobacco problem in India is very complex, due to large use of an array of smoking forms well as smokeless tobacco products. Several recent publications have highlighted the requirement for the dental profession to get involved with tobacco intervention. Although approximately all of the toxicity of smoking is due to other harmful components present in cigarette smoke, the pharmacological effects of nicotine leads to tobacco addiction. Hence, all the attempts to quit smoking are aimed to remove tobacco addiction by replacing tobacco nicotine with clean nicotine. The most important cessation aid used, out of all the cessation aids, is nicotine replacement therapy or NRT. Nicotine replacement therapy (NRT) replaces much of the nicotine from tobacco, which is mixed with harmful chemicals, with clean nicotine, thus reducing motivation to consume tobacco and also lessening nicotine withdrawal symptoms, thus easing the transition from cigarette smoking to complete abstinence. NRTs show good results and have minimal adverse effects. The review aims to summarize literature on various modes of nicotine replacement therapy methods currently used and to discuss future possible approaches. Also, the safety and need of NRTs in various special conditions have been discussed. Keywords: Nicotine replacement therapy, Important cessation, Cigarette smoking.