Urinary Nicotine Research Articles

Evaluation of the safety profile of an electronic vapour product used for two years by smokers in a real-life setting

The safety profile of Puritane™, a closed system electronic vapour product (EVP), was evaluated when used by smokers of conventional cigarettes (CCs) for 24 months in a real-life setting. The study was a two-centre ambulatory clinical study with 209 healthy volunteers. Outcome measures included adverse events (AEs), vital signs, electrocardiogram, lung function tests, exposure to nicotine and selected smoke constituents, nicotine withdrawal effects and smoking desire. No serious AEs related to EVP use were observed. The most frequently reported AEs were headache, nasopharyngitis, sore throat and cough, reported by 28.7%, 28.7%, 19.6% and 16.7% of subjects, respectively, which dissipated over time. Small decreases in lung function were not considered clinically relevant. No clinically relevant findings were observed in the other safety parameters. From Month 2, nicotine withdrawal symptoms decreased. Smoking desire and CC consumption steadily decreased over time in all subjects. EVP use was associated with reduced exposure to cigarette smoke constituents, whereas urinary nicotine levels remained close to baseline. Body weight did not increase in CC subjects switching to the EVP. In conclusion, the aerosol of the EVP at study was well tolerated and not associated with any clinically relevant health concerns after usage for up to 24 months.

Longitudinal Influence of Pregnancy on Nicotine Metabolic Pathways.

Nicotine metabolism increases in pregnancy, which may contribute to the difficulties that pregnant women have in quitting smoking. We aimed to determine the extent and timing of changes in nicotine metabolic pathways, including C-oxidation, N-glucuronidation, and the pregnancy-induced influences on the activity of enzymes mediating these pathways (CYP2A6 and UGT2B10, respectively). Current smoking pregnant women (n = 47) provided a urine sample during early pregnancy (12.5 weeks), late pregnancy (28.9 weeks), and 6 months postpartum. Concentrations of urinary nicotine and metabolites were analyzed using liquid chromatography tandem mass spectrometry and compared using general linear repeated measures analyses. Nicotine C-oxidation was 1.07-fold (P = 0.12) and 1.11-fold (P < 0.001) higher at early and late pregnancy, respectively, compared with postpartum. Nicotine N-glucuronidation was 1.33-fold (P = 0.06) and 1.67-fold (P = 0.003) higher at early and late pregnancy, respectively, compared with postpartum. The CYP2A6 phenotype ratio (total 3'-hydroxycotinine/cotinine) was significantly higher at early and late pregnancy compared with postpartum (all P < 0.05) and correlated with nicotine C-oxidation (all P < 0.001), suggesting CYP2A6 activity is induced during pregnancy. The UGT2B10 phenotype ratio (nicotine glucuronide/nicotine) was higher at early and late pregnancy compared with postpartum (P = 0.07 and P < 0.05, respectively) and correlated with a second UGT2B10 phenotype ratio (cotinine glucuronide/cotinine) (all P < 0.001), suggesting UGT2B10 activity is induced during pregnancy. In conclusion, pregnancy-induced increases in nicotine metabolism start by 12 weeks gestation and continue as pregnancy progresses most likely due to induction of CYP2A6 and UGT2B10, resulting in potential reductions in the effectiveness of nicotine replacement therapies and an increase in metabolism of other CYP2A6 and UGT2B10 substrates during pregnancy.

Validation of GC-MS Method for Determination of Nicotine and Cotinine in Plasma and Urine

Validation of GC-MS Method for Determination of Nicotine and Cotinine in Plasma and Urine

A high area, porous and resistant platinized stainless steel fiber coated by nanostructured polypyrrole for direct HS-SPME of nicotine in biological samples prior to GC-FID quantification.

The surface of a stainless steel fiber was made porous, resistant and cohesive using electrophoretic deposition and coated by the nanostructured polypyrrole using an amended in-situ electropolymerization method. The coated fiber was applied for direct extraction of nicotine in biological samples through a headspace solid-phase microextraction (HS-SPME) method followed by GC-FID determination. The effects of the important experimental variables on the efficiency of the developed HS-SPME-GC-FID method, including pH of sample solution, extraction temperature and time, stirring rate, and ionic strength were evaluated and optimized. Under the optimal experimental conditions, the calibration curve was linear over the range of 0.1-20μgmL-1 and the detection limit was obtained 20ngmL-1. Relative standard deviation (RSD, n=6) was calculated 7.6%. The results demonstrated the superiority of the proposed fiber compared with the most used commercial types. The proposed HS-SPME-GC-FID method was successfully used for the analysis of nicotine in urine and human plasma samples.

Interaction between cytochrome P450 2A6 and Catechol-O-Methyltransferase genes and their association with smoking risk in young men

BackgroundAlthough some effects of gene–gene interactions on nicotine–dopamine metabolism for smoking behavior have been reported, polymorphisms of cytochrome P450 (CYP) 2A6 and catechol-O-methyltransferase (COMT) have not been studied together to determine their effects on smokers. The aim of this study was to investigate the effects of the interaction between the CYP 2A6 and COMT genes on smoking behavior in young Taiwanese men.ResultsA self-report questionnaire regarding smoking status was administered to 500 young men. Polymorphisms of the CYP 2A6 and COMT genes as well as urinary nicotine and urinary cotinine levels were determined. The odds ratio for starting smoking was significantly lower in subjects carrying a CYP2A6 low activity/variant COMT rs4680 genotype than in those possessing a CYP2A6 wild-type/variant COMT rs4680 genotype (0.44, 95% confidence interval = 0.19–0.98, P = 0.043). Comparisons of Fagerstrom Test for Nicotine Dependence (FTND), Physiological Cigarette Dependence Scale (PCDS), and Cigarette Withdrawal symptoms (CWS-21) among the smokers with different CYP2A6/COMT polymorphisms were not significantly different. The adjusted urinary nicotine concentrations were not significantly different between the two groups carrying different genotypes. The adjusted urinary cotinine level was significantly different between the COMT rs4680 wild-type group and COMT rs4680 variant group [92.46 ng/μL vs. 118.24 ng/μL (median value), P = 0.041] and between the COMT rs4680 wild-type/COMT rs165599 variant group and COMT rs4680 variant/COMT rs165599 variant group (97.10 ng/μL vs. 122.18 ng/μL, P = 0.022).ConclusionsThese findings suggest that a single nucleotide polymorphism (rs4680) of the COMT gene and the interaction between the CYP 2A6 and COMT genes affect smoking status in young Taiwanese men.

금연 중 운동 유무에 따른 코티닌 배출 효과 비교

The objective of this study is to verify whether exercising of smokers provides a valid effect on emission of cotinine in urine and to suggest more effective way of quitting smoking through the exercise while stopping smoking. This study has been conducted with experiment for 6 weeks by classifying 21 male smokers into a control group (10 subjects) and experiment group (11 subjects) who were aged at 35 or above and decided to quit smoking. With control group, test has been conducted as to whether they smoked with urine nicotine kit for 2 times a week. With experiment group, subjects were asked to participate in aerobic exercise in the 65~70%HRmax for 50 minutes a time for three times per week while testing whether to smoke in the same conditions with the control group. Test on urine cotinine has been conducted for three times before the exercise and 3 and 6 weeks after the exercise, respectively Using SPSS/PC+ Win22.0 Version, mean and standard deviation in each item have been calculated. In order identify the difference of changes in urine cotinine depending on each group and measuring period, repeated measures ANOVA was used for the analysis. Significance level of p.05 in the verification process. According to the results of analysis, there was a difference in intra-object verification period (F=207.273, p.001). It also turned out that there was a difference in groups in verification process between objects (F=1.116, p.05). Therefore, aerobic exercise turned out to positively influence on the emission of cotinine through urine among smokers while stopping smoking.

Nicotine metabolism by the flavin monooxygenase (FMO) family of enzymes.

Nicotine is the addictive tobacco‐specific alkaloid present in cigarettes. Nicotine is metabolized in vivo primarily by hydroxylation by CYP2A6, but is also glucuronidated by UDP‐glucuronosyltransferases (UGTs) and oxidized by FMOs. Nicotine‐N‐oxide has been detected in smoker's urine, accounting for 4–8% of total urinary nicotine metabolites. While previous studies have suggested that the hepatic FMO3 is the principal enzyme involved in nicotine‐N‐oxidation, a comprehensive analysis of nicotine oxidation by all FMOs has not previously been performed. To characterize the catalytic activity of FMOs in the formation of nicotine‐N‐oxide, wild‐type FMOs 1 through 5 were individually overexpressed in HEK293 cells and used in oxidation reactions containing between 0.1 – 5000 μM of (−)‐nicotine and NADPH‐regenerative system; nicotine‐N‐oxide formation was monitored by UPLC‐MS/MS. While all five FMOs exhibited oxidation activity against nicotine, only FMO1 exhibited a KM of less than 1 mM (0.76 mM), with FMOs 3, 4 and 5 all exhibiting a KM of &gt;40 mM. While FMO2 is expressed primarily in the lung and possibly brain, this enzyme is functional only in people of African ancestry due to a SNP in the FMO2 stop codon (codon 472; MAF=0.15); most of the remaining human population expresses a truncated non‐functional enzyme. Functional FMO2427Gln also exhibited low activity against nicotine, with a KM = 71 mM. Non‐synonymous polymorphic variants for FMO1 and FMO3 have been overexpressed in HEK293 cells and are currently being screened for activity against nicotine in vitro. These data are consistent with FMO1 being the principal enzyme involved in nicotine‐N‐oxidation and with previous studies demonstrating that functional genetic variants in FMO1 are associated with differences in nicotine dependence.Support or Funding Information National Institutes of Health, National Institutes of Environmental Health Sciences [Grant R01‐ES025460] Health Sciences and Services Authority of Spokane, WA [Grant WSU002292]

Do Parental Smoking Habits Differ in Children with Asthma/Wheezing Disorders?

Objective: Second-hand smoke exposure in children is a recognized risk factor for asthma/wheezing. Even brief exposure can be harmful. Adult smoking prevalence in Greece is of the highest worldwide and pediatric asthma rates are raising. Our objective was to investigate parental smoking habits in homes of children with and without bronchial asthma/wheezing disorders. Methods: This is a case-control study that included 90 children aged 1, 5-17 years old subdivided into two groups: 51 children with asthma/wheezing and 39 healthy peers. SHS exposure was estimated by both questionnaires on smoking habits reported by parents and urinary nicotine and cotinine levels in children. Results: Based on both questionnaires and urinary biomarkers, smoking habits between two groups were not significant (p=0.291). Urinary cotinine assays unveild more children to be exposed to SHS (98% in cases and 89.4% in controls) than reported by their parents (62.75% in cases and 66.6% in controls). More cases were heavier exposed to SHS than controls (>10 ng/ml). Home smoking restrictions between two groups didn’t reach statistical significance though they were found to affect urinary cotinine levels in children. Conclusions: Parental smoking habits do not differ between families of children with and without asthma/ wheezing disorders. Parents, especially those nurturing a child with respiratory tract disease, tend to underreport SHS exposure.

Application of solvent demulsification dispersive liquid–liquid microextraction for nicotine and cotinine measurement in human urine combined with hydrophilic interaction chromatography tandem mass spectrometry

A SD-DLLME-HILIC-MS method was established and applied for human urinary nicotine and cotinine measurement to evaluate tobacco exposure.

ED01.02 Tobacco Carcinogens and Lung Cancer Susceptibility

ED01.02 Tobacco Carcinogens and Lung Cancer Susceptibility

Electrochemical sensing of nicotine using screen-printed carbon electrodes modified with nitrogen-doped graphene sheets

Rapid and accurate detection of nicotine is important due to its detrimental effects on human beings and recent surge in the usage of electronic cigarettes. In this paper, we report an electrochemical sensor for nicotine detection by using screen-printed carbon electrodes (SPCE) modified with nitrogen-doped graphene sheets (NGS). NGS was synthesized and characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Raman spectrometry. Due to the superior electron transfer capability and the doped nitrogen atoms, NGS shows high catalytic activity for the electro-oxidation of nicotine, with a significant decrease in the overpotential. Using the NGS-based nicotine sensor, we obtained detection sensitivity at 0.627mA·cm−2mM−1 with the limit of detection at 47nM nicotine. Moreover, the sensor shows favorable selectivity and long-term stability for detecting nicotine in urine and tobacco samples.

Nicotine levels, withdrawal symptoms, and smoking reduction success in real world use: A comparison of cigarette smokers and dual users of both cigarettes and E-cigarettes

IntroductionTo evaluate how experienced dual users used cigarettes and e-cigarettes in real-world use and under different levels of cigarette availability. MethodsDual users (cigarettes+e-cigarettes; n=74) and a smoke-only group (just cigarettes; n=74) engaged in a 26-day study with two ad lib use intervals, a week of 75% cigarette reduction and three days of 100% cigarette reduction. After a week of ad lib use of products, all participants were asked to reduce smoking by 75% (dual users were free to use their e-cigarettes as they wished), followed by another week of ad lib use. All participants were then asked to reduce smoking by 100% (cessation) for three days. Primary outcomes were biological samples (carbon monoxide, urinary nicotine and cotinine). Participants also provided real-time reports of product use, craving, and withdrawal symptoms using a smartphone app. ResultsDual users did not smoke fewer cigarettes than smoke-only participants during ad lib periods, but quadrupled their use of e-cigarettes during smoking reduction periods. Dual users were significantly more likely to maintain 100% reduction (97.1% vs. 81.2%). Amongst women, dual use was associated with higher nicotine levels and withdrawal suppression. DiscussionAmong a group of experienced dual users, e-cigarettes helped maintain smoking reduction and reduced some withdrawal symptoms, although both withdrawal symptoms and nicotine levels varied as a function of gender.

Evaluation of the Tobacco Heating System 2.2. Part 6: 90-day OECD 413 rat inhalation study with systems toxicology endpoints demonstrates reduced exposure effects of a mentholated version compared with mentholated and non-mentholated cigarette smoke

The toxicity of a mentholated version of the Tobacco Heating System (THS2.2M), a candidate modified risk tobacco product (MRTP), was characterized in a 90-day OECD inhalation study. Differential gene and protein expression analysis of nasal epithelium and lung tissue was also performed to record exposure effects at the molecular level.Rats were exposed to filtered air (sham), to THS2.2M (at 15, 23 and 50 μg nicotine/l), to two mentholated reference cigarettes (MRC) (at 23 μg nicotine/l), or to the 3R4F reference cigarette (at 23 μg nicotine/l). MRCs were designed to meet 3R4F specifications.Test atmosphere analyses demonstrated that aldehydes were reduced by 75%–90% and carbon monoxide by 98% in THS2.2M aerosol compared with MRC smoke; aerosol uptake was confirmed by carboxyhemoglobin and menthol concentrations in blood, and by the quantities of urinary nicotine metabolites.Systemic toxicity and alterations in the respiratory tract were significantly lower in THS2.2M-exposed rats compared with MRC and 3R4F. Pulmonary inflammation and the magnitude of the changes in gene and protein expression were also dramatically lower after THS2.2M exposure compared with MRCs and 3R4F.No menthol-related effects were observed after MRC mainstream smoke-exposure compared with 3R4F.

A randomised, parallel group study to evaluate the safety profile of an electronic vapour product over 12 weeks

A randomised, parallel group clinical study was performed to evaluate the safety profile of an e-vapour product (EVP; 2.0% nicotine) in smokers of conventional cigarettes (CCs) switching to use the EVP for 12 weeks. During the study, no clinically significant product-related findings were observed in terms of vital signs, electrocardiogram, lung function tests and standard clinical laboratory parameters. Adverse events (AEs) reported by EVP subjects were more frequent during the first week after switching to the EVP. The frequency of AEs reduced thereafter and out of a total of 1515 reported AEs, 495 were judged as being related to nicotine withdrawal symptoms. The most frequently stated AEs were headache, sore throat, desire to smoke and cough reported by 47.4, 27.8, 27.5 and 17.0% of subjects, respectively. Only 6% of AEs were judged as probably or definitely related to the EVP. Additional observations in EVP subjects included a decrease in the level of urine nicotine equivalents by up to 33.8%, and decreases in the level of three biomarkers of exposure to toxicants known to be present in CC smoke (benzene, acrolein and 4-[methylnitrosamino]-1-[3-pyridyl]-1-butanone). The decrease in nicotine equivalents coincided with an increase in nicotine withdrawal symptoms, measured by a questionnaire, which subsided after two weeks. The data presented here shows the potential EVPs may offer smokers looking for an alternative to CCs.

Subchronic inhalation toxicity study of 3R4F reference cigarette smoke in rats

This study aimed to investigate the subchronic exposure toxicity of smoke from 3R4F reference cigarettes. Male and female Sprague-Dawley rats were exposed to cigarette smoke at total particulate matter (TPM) concentrations of 50, 100, or 200 μg/L for a period of 13 weeks. Body weight gain of male rats significantly decreased upon exposure to 200 μg TPM/L of smoke. All smoke-exposed groups showed increase in blood carboxyhemoglobin, urinary nicotine and its metabolites, and inflammatory cytokines relative to the control group. Increased alveolar macrophages, pigmented and thickened alveolar walls, and hypertrophy/hyperplasia were observed in the lungs at concentrations above 50 μg TPM/L. These changes were related to the increase in absolute or relative lung weights. Histopathological examination revealed cigarette smoke-related changes in the nasal cavity, larynx, and trachea. The respiratory tract was adversely affected by inhalation of cigarette smoke. We identified that blood carboxyhemoglobin, urinary nicotine and its metabolites were tobacco-specific biomarkers, and suggested that CXCL1, CCL2, IL-1β, IL-10, TIMP-1, TIMP-2 were useful biomarkers for cigarette smoke. These results may serve as reference data to compare toxicity of tobacco products.

Urinary Polycyclic Aromatic Hydrocarbons: simultaneous determination of metabolites in human biomonitoring studies

Introduction: exposure assessment of residents in industrial areas is a crucial issue in environmental epidemiology . We propose a novel analytical method for simultaneous quantification of urinary polycyclic aromatic hydrocarbons metabolites (OH-PHAs), to assess exposure to urban pollution, diesel exhaust and biomass burning and to verify the contribution of smoking to the selected biomarkers . Method: 1-hydroxypyrene, 1-and 2-hydroxynapthalene, 3-hydroxybenzo[a]pyrene, 6-hydroxynitropyrene were measured in the urine samples of 614 healthy residents in an industrial area of Central Italy, aged 35-69 years, non-occupationally exposed to PAHs. Samples were subjected to enzymatic hydrolysis, to SPE, and further analyzed on ESI-HPLC-MS/MS in the negative ion MRM mode, using isotope labelled internal standards. Smoking status was assessed by measuring urinary nicotine metabolite (cotinine) levels. We studied the association between each OH-PAH log-transformed value and cotinine levels (&lt;100 µg/l, ≥100 µg/l) by using regression analysis (Geometric Mean Ratios (GMR) and p-value). Results: method accuracy was never less than 90%, variability never higher than 19%, and limits of detection were low enough to detect the five proposed biomarkers in the general population. 6-OHNP was present in the 65% of the subjects and 3-OHBaP in the 70% and the concentrations of these metabolites were not affected by smoking: we found no association between their log-transformed values and cotinine levels (GMR=1.33 (p=0.137) for 6-OHNP; GMR=1.05 (p=0.825) for 3-OHBaP). Conclusion: The novel HPLC-MS/MS method made it possible to simultaneously quantitate a metabolite of nitropyrene, a diesel exhaust pollution marker, and a metabolite of benzo[a]pyrene, a IARC class 1 carcinogenic substance, other than more known and usually determined metabolites; the fact that 6-OHNP and 3-OHBaP are not affected by smoking makes these biomarkers suitable for studying exposure to environmental pollution.

Reductions in biomarkers of exposure (BoE) to harmful or potentially harmful constituents (HPHCs) following partial or complete substitution of cigarettes with electronic cigarettes in adult smokers

Changes in fifteen urine, blood and exhaled breath BoEs of HPHCs representing classes of compounds reported by FDA to be significant contributors to smoking-associated disease risks were measured in 105 clinical-confined subjects following randomization and a five-day forced-switch from usual brand conventional combustible cigarettes to: (i) exclusive commercial e-cigarette use; (ii) dual-use of commercial e-cigarettes and the subject’s usual cigarette brand; or (iii) discontinued use of all tobacco or nicotine products. Levels of urinary biomarkers in subjects that completely substituted their usual cigarette with e-cigarettes were significantly lower (29–95%) after 5 days. Percent reductions in eight of nine urinary BoEs were indistinguishable to smokers who had quit smoking, except for nicotine equivalents, which declined by 25–40%. Dual users who halved self-reported daily cigarette consumption with e-cigarettes exhibited reductions (7–38%) in eight of nine urinary biomarkers, but had increase (1–20%) in nicotine equivalents. Reductions were broadly proportional to the reduced numbers of cigarettes smoked. Dual user urinary nicotine equivalents were slightly higher, but not statistically significant. After 5 days, blood nicotine biomarker levels were lower in the cessation (75–96%) and exclusive use groups (11–83%); with dual users experiencing no significant reductions. All subjects experienced significant decreases in exhaled CO. Decreases in the cessation and exclusive groups ranged from 88–89% and 27–32% in dual users. Exhaled NO increased in the cessation and exclusive groups (46–63% respectively), whereas the dual users experienced minimal changes. Overall, smokers who completely or partially substituted conventional cigarettes with e-cigarettes over five days, experienced reductions in HPHCs.

Nicotine Dependence and Urinary Nicotine, Cotinine and Hydroxycotinine Levels in Daily Smokers.

Nicotine dependence and smoking frequency are critical factors for smoking cessation. The aims of this study are (1) to determine if nicotine dependence Fagerström Test for Nicotine Dependence (FTND) scores are associated with urinary levels of nicotine metabolites, (2) to assess the relationship of hydroxycotinine/cotinine ratio with FTND score and cigarettes smoked per day (CPD), and (3) to identify significant predictors of cigarettes per day among biomarker concentrations and individual FTND items. Urine samples and questionnaire data of 239 daily smokers were obtained. Nicotine, cotinine and hydroxycotinine urinary levels were determined by UPLC MS/MS.Multiple linear regression models were developed to explore the relationship between nicotine, cotinine, hydroxycotinine levels and separate FTND scores (for all six items). We found significant correlations between the different urinary biomarker concentrations, and the FTND score. The time before the first cigarette after waking (TTFC) was significantly associated with the nicotine, cotinine and hydroxycotinine concentrations. No association was found between the ratio of hydroxycotinine to cotinine and either the FTND or the CPD. A model including four FTND questions, sex, age, and the cotinine concentration, accounted for 45% of the variance of CPD. There are significant relationships between urinary levels of nicotine, cotinine, and hydroxycotinine and the FTND score. Especially the FTND question about TTFC is relevant for explaining the biomarker concentrations. CPD (below 15) was significantly explained by four FTND dependence items and urinary cotinine levels in a regression model. We investigated associations between urinary levels of nicotine, cotinine, and hydroxycotinine in daily smokers and the FTND scores for nicotine dependence. We did not find association between the hydroxycotinine/cotinine ratio and CPD. We developed a model that explains the cigarettes smoked daily (CPD) in a group of light smokers by combining FTND items, urinary cotinine levels, sex, and age. Our results might be of importance for clinical use or future studies on larger smoking populations.

Nicotine dependence and urinary nicotine, cotinine and hydroxycotinine levels in daily smokers

Nicotine dependence and urinary nicotine, cotinine and hydroxycotinine levels in daily smokers

Evaluation of Urinary Btex, Nicotine, and Cotinine as Biomarkers of Airborne Pollutants in Nonsmokers and Smokers

Benzene, toluene, ethylbenzene, and isomeric xylenes (BTEX) are by-products of tobacco smoke and traffic emissions. The aim of this study was to determine the contribution of cigarette smoking to urinary levels of BTEX present in humans. Nicotine and cotinine, biomarkers of exposure to tobacco smoke, as well as BTEX, were measured in urine of smokers (n = 70) and nonsmokers (n = 65) using headspace solid-phase microextraction (HS-SPME) followed by gas chromatography–mass spectrometry (GC-MS). In smokers, a significant correlation was found between urinary BTEX levels and nicotine and cotinine. In addition, significant regression models with nicotine and cotinine as predictors showed that BTEX in smokers’ urine was predominantly derived from exposure to tobacco smoke. In nonsmokers a weak correlation between BTEX and nicotine and cotinine was found in urine. Further, there was a lack of significant contribution of BTEX to urinary nicotine and cotinine concentrations in nonsmokers. Thus, it was presumed that vehicle exhaust was the main source of exposure to BTEX in nonsmokers.