Urinary Nicotine Research Articles

Associations of urinary nicotine metabolites and essential metals with metabolic syndrome in older adults: The mediation effect of insulin resistance

Exposure to tobacco smoke and essential metals is linked with metabolic syndrome (MS). However, the joint effect of them on MS in older adults and the underlying mechanisms are still unclear. This large-scale study measured the urinary concentrations of 8 nicotine metabolites and 8 essential metals in 4564 older adults from Shenzhen, China. The biomarker of insulin resistance, triglyceride-glucose index (TyG), was also calculated. Restricted cubic splines (RCS), Bayesian kernel machine regression and quantile-based g-computation were used to access the single and joint effects of urinary nicotine metabolites and essential metals on MS and insulin resistance. Mediation analysis was performed to investigate the role of TyG in these relationships.Single urinary nicotine metabolite and essential metal had non-linear relationships with MS in RCS. The overall effect of urinary nicotine metabolites and essential metals was positively associated with MS. Urinary zinc (52.2 %) and copper (20.1 %) were the major contributors to MS, whereas molybdenum had a negative association with MS. TyG mediated 64.7 % of the overall effect of urinary nicotine metabolites and essential metals on MS. Overall, the mixture of urinary nicotine metabolites and essential metals had a dose-response relationship with MS. Insulin resistance was as a crucial mediated pathway in this association.

Gas chromatography-mass spectrometry determination of nicotine and cotinine in urine: A study of the effect of passive smoking.

Recent data suggest that passive smoking has a risk comparable to active smoking. Passive smoking is considered dangerous in children and is suspected as a cause of asthma. However, some reports are opposing such claims, indicating the need for solid results and large-scale studies. This scientific work aims to develop a method for the determination of nicotine (NCOT) and major nicotine's metabolite cotinine (COT) in urine samples, using gas chromatography-mass spectrometry (GC-MS). Analysis was performed using a gas chromatograph Agilent Technologies 7890A with an MS 5975C inert XL, EI/CI MSD with Triple-Axis detector. For sample preparation, liquid-liquid extraction was applied after an optimization study with different extraction media. Eventually, 1 mL of dichloromethane was selected for the extraction of 0.5mL of urine. Suitable chromatographic conditions were found for the rapid and accurate determination of NCOT and COT. Injection of 2μL was performed using GC-MS, and selected ion monitoring (SIM) analysis was performed with the following ions (m/z): 162 (quantifier ion) and 84, 133, 161 qualifier ions for NCOT, and 176 (quantifier ion) and 98, 118, 119, 147 qualifier ions for COT. Nicotine-D4 (NCOT-D4) and cotinine-D3 (COT-D3) were used as internal standards with quantifier ions 101 and 166, respectively. The retention time (Rt) for NCOT was 7.557 min and 9.743 min for COT. The method was validated following international principles, assessing characteristics such as absolute recovery, carryover, linearity, specificity, selectivity, accuracy, precision, and stability. The method showed a linear dynamic range from 0.5 to 50 ng/mL, and the limits of detection and quantification were for both NCOT and COT 0.2 and 0.5 ng/mL, respectively. Validation results were found satisfactory.Finally, the method was applied to the analysis of 60 clinical pediatric samples obtained from Aristotle University's pediatric clinic to check for possible exposure to smoke. Concentration levels ranged between 0.5 and 16.2ng/mL for NCOT and between 1.0 and 25.1ng/mL for COT. A rapid, sensitive, accurate, and simple method was developed and used as a tool for the confirmation of passive smoking in children. It is the first method applied to the analysis of such samples belonging to nonsmokers of young age. The total runtime of the GC-MS analysis was short (20 min), and the pretreatment protocol was simple, giving the ability for analysis of a large number of samples on a daily routine basis.

Biomarker Assessment of Nicotine Exposure Among Adolescent E-Cigarette Users: 2018-2019.

Despite the increasing prevalence of vaping e-cigarettes among adolescents, there remains a lack of population-level assessments regarding the objective measurement of nicotine exposure. This study analyzed a nationally representative sample of adolescents aged 13 to 17 years from Wave 5 of the Population Assessment of Tobacco and Health Study conducted between 2018 and 2019. Urinary nicotine metabolites, including cotinine and trans-3'-hydroxycotinine (3-HC), were assessed among exclusive nonnicotine e-cigarette users (n = 56), exclusive nicotine e-cigarette users (n = 200), and nonusers (n = 1059). We further examined nicotine exposure by past 30-day vaping frequency (ie, occasional [1-5 days], intermittent [6-19 days], and frequent [20+ days]) and flavor types among nicotine e-cigarette users. Multivariable linear regressions tested pairwise group effects, and biomarkers were normalized by the log transformation. Compared with nonusers, both nonnicotine and nicotine e-cigarette users exhibited higher levels of cotinine and 3-HC. Nicotine e-cigarette users had mean cotinine concentrations (61.3; 95% confidence interval, 23.8-158.0, ng/mg creatinine) approximately 146 times higher (P < .0001) than nonusers (0.4; 0.3-0.5), whereas nonnicotine users (4.9; 1.0-23.2) exhibited cotinine concentrations ∼12 times higher (P = .02). Among nicotine e-cigarette users, the levels of cotinine and 3-HC increased by vaping frequency, with cotinine increasing from 10.1 (2.5-40.1) among occasional users to 73.6 (31.8-170.6) among intermittent users and 949.1 (482.5-1866.9) among frequent users. Nicotine exposure was not significantly different by flavor type. E-cigarette use poses health-related risks resulting from nicotine exposure among adolescents. Comprehensive regulations of e-cigarette products and marketing, vaping prevention, cessation, and public policies are needed to prevent youth from developing nicotine addiction.

Quantitation of Urine Nicotine, Cotinine, and 3-OH-Cotinine by Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS).

Nicotine is a naturally occurring and highly addictive chemical used in e-cigarettes, cigarettes, chewing tobacco, and other tobacco products as well as in nicotine replacement therapies. The negative health consequences of using nicotine-containing products are well known. In fact, smoking remains the leading cause of preventable disease, disability, and death in the United States. Measurement of nicotine and its metabolites, cotinine and 3-OH-cotinine, offers an objective method to evaluate nicotine exposure and the associated health risks. In this chapter, we describe a quick and reliable isotope dilution LC-MS/MS method for the quantitation of these three compounds in 60μL of human urine following a simple sample preparation procedure. Electrospray Ionization (ESI) in positive mode is used to introduce the analytes into the mass spectrometer and quantitation is achieved using Multiple Reaction Monitoring (MRM). The analytical measurable ranges for nicotine and cotinine are 10-2500ng/mL and 20-5000ng/mL for 3-OH-cotinine.

New Au/chitosan nanocomposite modified carbon paste sensor for voltammetric detection of nicotine

A profoundly touchy voltammetric sensor for detection of nicotine (NIC) in urine and tobacco specimens has been developed in light of the boosted electrochemical response of NIC at gold and chitosan nanocomposite modified carbon paste electrode (ACMCPE). Material characterization techniques Scanning Electron Microscope and Energy Dispersive X-ray (SEM & EDX) were utilized to describe the ACMCPE surface material. The impedance spectroscopy technique (EIS), cyclic voltammetry (CV), chronoamperometry (CA), and differential pulse voltammetry (DPV) were employed to explore the electrochemical sensing of NIC at ACMCPE. The created sensor exhibits an exceptional electrochemical sensitivity to NIC in a universal Britton–Robinson (B-R) buffer solution with a pH range of 2.0 to 8.0. The sensor shows a linear response over NIC concentration ranges of 4.0–320.0 µM, with the detection limit (LOD) of 7.6 µM. The prepared sensor has been shown to be exceptionally viable in detecting NIC with amazing selectivity and reproducibility. We suggest it as a trustworthy and useful electrochemical sensor for NIC location.

Simultaneous Measurement and Distribution Analysis of Urinary Nicotine, Cotinine, Trans-3′-Hydroxycotinine, Nornicotine, Anabasine, and Total Nicotine Equivalents in a Large Korean Population

Measurement of multiple nicotine metabolites and total nicotine equivalents (TNE) might be a more reliable strategy for tobacco exposure verification than measuring single urinary cotinine alone. We simultaneously measured nicotine, cotinine, 3-OH cotinine, nornicotine, and anabasine using 19,874 urine samples collected from the Korean National Health and Nutrition Examination Survey. Of all samples, 18.6% were positive for cotinine, 17.4% for nicotine, 17.3% for nornicotine, 17.6% for 3-OH cotinine, and 13.2% for anabasine. Of the cotinine negative samples, less than 0.3% were positive for all nicotine metabolites, but not for anabasine (5.7%). The agreement of the classification of smoking status by cotinine combined with nicotine metabolites was 0.982–0.994 (Cohen’s kappa). TNE3 (the molar sum of urinary nicotine, cotinine, and 3-OH cotinine) was most strongly correlated with cotinine compared to the other nicotine metabolites; however, anabasine was less strongly correlated with other biomarkers. Among anabasine-positive samples, 30% were negative for nicotine or its metabolites, and 25% were undetectable. Our study shows that the single measurement of urinary cotinine is simple and has a comparable classification of smoking status to differentiate between current smokers and non-smokers relative to the measurement of multiple nicotine metabolites. However, measurement of multiple nicotine metabolites and TNE3 could be useful for monitoring exposure to low-level or secondhand smoke exposure and for determining individual differences in nicotine metabolism. Geometric or cultural factors should be considered for the differentiation of tobacco use from patients with nicotine replacement therapy by anabasine.

The effects of nicotine use during adolescence and young adulthood on gray matter cerebral blood flow estimates.

Nicotine and tobacco product (NTP) use remains prevalent in adolescence/young adulthood. The effects of NTPs on markers of brain health during this vulnerable neurodevelopmental period remain largely unknown. This report investigates associations between NTP use and gray matter cerebral blood flow (CBF) in adolescents/young adults. Adolescent/young adult (16-22 years-old) nicotine users (NTP; N = 99; 40 women) and non-users (non-NTP; N = 95; 56 women) underwent neuroimaging sessions including anatomical and optimized pseudo-continuous arterial spin labeling scans. Groups were compared on whole-brain gray matter CBF estimates and their relation to age and sex at birth. Follow-up analyses assessed correlations between identified CBF clusters and NTP recency and dependence measures. Controlling for age and sex, the NTP vs. non-NTP contrast revealed a single cluster that survived thresholding which included portions of bilateral precuneus (voxel-wise alpha < 0.001, cluster-wise alpha < 0.05; ≥7 contiguous voxels). An interaction between NTP group contrast and age was observed in two clusters including regions of the left posterior cingulate (PCC)/lingual gyrus and right anterior cingulate cortex (ACC): non-NTP exhibited positive correlations between CBF and age in these clusters, whereas NTP exhibited negative correlations between CBF and age. Lower CBF from these three clusters correlated with urine cotinine (rs=-0.21 - - 0.16; ps < 0.04) and nicotine dependence severity (rs=-0.16 - - 0.13; ps < 0.07). This is the first investigation of gray matter CBF in adolescent/young adult users of NTPs. The results are consistent with literature on adults showing age- and nicotine-related declines in CBF and identify the precuneus/PCC and ACC as potential key regions subserving the development of nicotine dependence.

SAT496 Tobacco Smoking May Mimic Subclinical Hyperthyroidism

Abstract Disclosure: R. Alshantti: None. U. Rafat: None. B. Alkhaurri: None. C.P. Barsano: None. M. Siddiqui: None. Introduction: Studies have shown lower levels of TSH in smokers and a positive association of smoking with hyperthyroidism. The urinary nicotine level is reported to be negatively correlated with TSH. Moreover, smoking cessation have shown reversible effects on thyroid functions and risk of having overt hypothyroidism increased more than 6-fold in the first 2 years after cessation of smoking. Whether transient smoking cessation, prior to blood work would alter thyroid functions is unknown. We report the case of an elderly woman who had normalization of suppressed TSH after smoking abstinence prior to her blood work, suggestive of smoking-induced alteration of the TSH level. Clinical Case: A 77- year-old woman was referred to endocrinology clinic for an abnormal TSH level. She had a suppressed TSH &amp;lt;0.01 uIU/mL [Ref range: 0.45-5.33], with normal free T4 0.78 ng/dl [Ref range: 0.70-2.70], and free T3 3.66 pg/ml [Ref range: 2.5-3.9], consistent with subclinical hyperthyroidism. Thyroid auto-antibodies were negative. She had a long-standing history of multinodular goiter with mild tracheal deviation for which she had declined surgical management. She was an active smoker with 40 pack years smoking history. There was no preceding viral illness. She was not taking any biotin-containing supplements or medications that would interfere with thyroid hormones. The patient denied symptoms of overt hyperthyroidism. On physical examination she had a large multinodular goiter with negative Pemberton’s sign. There was no exophthalmos, lid lag, tachycardia, tremors or hyperreflexia. Her subsequent blood tests, 2 and 4 months apart, were also consistent with subclinical hyperthyroidism with TSH levels of 0.115 to 0.144 uIU/mL with normal free T4 0.72 ng/dl and total T3 136.3 to 153 ng/dl [Ref range 80-187]. Based on her age, she met the treatment threshold. However, as the patient continued to smoke 10 cigarettes daily, even on the days when thyroid labs were drawn, treatment was deferred considering the possibility of smoking-induced altered thyroid function. Blood work re-drawn after a smoking abstinence of 10-12 hours showed normalization of TSH 0.58 uIU/mL consistent with a euthyroid state. Conclusion: When evaluating patients with abnormal thyroid functions, it is important to address smoking status. Cigarette smoking may alter thyroid function tests in a pattern consistent with subclinical or overt hyperthyroidism and its effect on thyroid functions may be transient and reversible. Therefore, the possibility of smoking-induced alteration of thyroid functions should be considered in active, clinically euthyroid smokers. It may be judicious to hold treatment with thionamides in such patients and to re-evaluate thyroid functions after smoking abstinence. Presentation Date: Saturday, June 17, 2023

Urinary nicotine metabolites are associated with cognitive impairment among the elderly in southern China.

This study comprehensively assessed the association between eight metabolites of urinary nicotine and cognitive impairment. This cross-sectional study was based on the data of Shenzhen Aging Related Disorder Cohort (SADC), including 51 elderly community data variables such as demographic characteristics, neuropsychological assessment and environmental factors, from July 2017 to November 2018. Participant's cognitive function was assessed by Mini-Mental State Examination (MMSE) scale and urinary nicotine metabolite [including cotinine N-β-D-glucuronide (CotGluc), rac 4-hydroxy-4-(3-pyridyl) butanoic acid dicyclohexylamine salt (HyPyBut), trans-3'-hydroxy cotinine O-β-D-glucuronide (OHCotGluc), and cotinine (Cot), etc.] concentrations were measured by high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS). Generalized linear models and restricted cubic spline models were used to explore the relationships between the urinary levels of nicotine metabolite and cognitive function. A total of 296 individuals aged >60 years were included. Individuals in the third quartile of CotGluc had a 0.786 point (95% CI: -1.244 - -0.329) decrease or in the highest quartile of OHCotGluc had a 0.804 point (95% CI: -1.330 - -0.278) decreased in attention and calculation compared to those in the lowest quartile (all p for trend <0.05). Compared with those in the lowest quartile, individuals in the highest quartile of CotGluc, HyPyBut, OHCotGluc and Cot, respectively, corresponded to a 1.043 point (95% CI: -2.269-0.182), 1.101 points (95% CI: -2.391-0.188), 2.318 points (95% CI: -3.615 - -1.020), and 1.460 points (95% CI: -2.726 - -0.194) decreased in MMSE total score (all p for trend <0.05). A non-linear dose-response relationship between urinary levels of CotGluc, HyPyBut, OHCotGluc or Cot and cognitive function (all overall p<0.05, non-linear p<0.05). Subgroup analysis showed that urinary levels of CotGluc, OHCotGluc or Cot were significantly negatively associated with cognitive function (all p for trend <0.05) among females and non-smokers. The findings highlight the public health implications of environmental tobacco smoke exposure, and effective interventions need to be performed for vulnerable populations.

Biochemical and genetic biomarkers associated with nicotine dependence in Mexican smokers.

Cigarette smoking remains an important health concern and is still a leading cause of preventable mortality. Nicotine is the substance responsible for sustained tobacco use and dependence. Identification of biomarkers underlying nicotine dependence behavior is important to identify people at risk for this dependence. In the present study, we identified biochemical and genetic biomarkers of nicotine dependence detected by the Fagerström Test for Nicotine Dependence (FTDN) in Mexican smokers. The nicotine metabolites nicotine-N'-oxide, trans-3'-hydroxycotinine-glucuronide (3HC-O-Gluc), and nicotine-N-Gluc (Gluc) were useful to differentiate nicotine-dependent from non-dependent subjects (p < .0001) with an area under the curve (AUC) of 0.7818. Genetic variants in CYP2A6, FMO3, and UGT2B7 (rs2431413, rs28363545, and rs7439326, respectively) were associated with nicotine dependence (p = .03, p = .01, p = .01, respectively). Variations in the enzymatic activity of CYP2A6 were associated with altered nicotine-N'-oxide and 3HC-O-Gluc levels. Decreased urinary levels of 3HC-O-Gluc and increased nicotine-N'-oxide were associated with a decrease in the functional activity of CYP2A6. A strong positive correlation was observed between the ratio of urinary 3HC/cotinine, a measure of CYP2A6 activity, and the levels of 3HC-O-Gluc (p < .0001, r = .6835), while a strong negative correlation was observed with nicotine-N'-oxide (p < .0001, r = .6522) in nicotine-dependent subjects. No correlations were observed in non-nicotine-dependent subjects. These data suggest that particular urinary nicotine metabolites and genetic variants involved in nicotine metabolism are useful to identify subjects with nicotine dependence in the Mexican population.

Effects of Short-term Electronic(e)-Cigarette Aerosol Exposure in the Mouse Larynx.

The effects of electronic cigarettes (e-cigarettes) on the larynx are relatively unknown. This study examined the short-term effects of e-cigarette inhalation on cellular and inflammatory responses within the mouse laryngeal glottic and subglottic regions after exposure to pod-based devices (JUUL). Male C57BL6/J mice (8-9 weeks) were assigned to control (n = 9), JUUL flavors Mint (JMi; n = 10) or Mango (JMa; n = 10). JUUL mice were exposed to 2 h/day for 1, 5, and 10 days using the inExpose inhalation system. Control mice were in room air. Vocal fold (VF) epithelial thickness, cell proliferation, subglandular area and composition, inflammatory cell infiltration, and surface topography were evaluated in the harvested larynges. Mouse body weight and urinary nicotine biomarkers were also measured. Chemical analysis of JUUL aerosols was conducted using selective ion flow tube mass spectrometry. JUUL-exposed mice had reduced body weight after day 5. Urinary nicotine biomarker levels indicated successful JUUL exposure and metabolism. Quantitative analysis of JUUL aerosol indicated that chemical constituents differ between JMi and JMa flavors. VF epithelial thickness, cellular proliferation, glandular area, and surface topography remained unchanged after JUUL exposures. Acidic mucus content increased after 1 day of JMi exposure. VF macrophage and T-cell levels slightly increased after 10 days of JMi exposures. Short-term e-cigarette exposures cause minimal flavor- and region-specific cellular and inflammatory changes in the mouse larynx. This work provides a foundation for long-term studies to determine if these responses are altered with multiple e-cigarette components and concentrations. N/A Laryngoscope, 134:1316-1326, 2024.

Investigation of the relationship between nicotine and cotinine concentrations in human biological samples by a GC-MS method

In this study, a gas chromatography-mass spectrometry method was developed for the determination of nicotine and cotinine wherein human plasma, urine, and saliva. In addition, it was aimed to determine statistically the correlation between nicotine and cotinine levels in urine and saliva samples and nicotine and cotinine levels in blood samples. The limit of quantification was ≤0.83 ng/mL and precision were ≤4.91 and accuracy (RE%) was between (-4.93) and 4.90. Recovery was detected between 95.4% and 104.7%. The method was employed to determining the nicotine and cotinine concentrations in plasma, saliva, and urine total of 91 samples belong to non-smokers (n=37) and active smokers (n=54) who were healthy (n=65) and COPD patients (n=27) and the statistical relationship within the nicotine and cotinine values of the samples were investigated. It was found a correlation (r=0.752, p≤0.01) between plasma and saliva cotinine levels and estimation equation calculated as y=1.56x+43.24. Also, the correlation between plasma and urine cotinine levels was found (r=0.787, p≤0.01) by the equation that y=0.31x+34.59. The results show that by accurately determining the amount of cotinine in both saliva and urine, the exposure risks of both active smokers and those exposed to cigarette smoke with the ETS can be estimated.

Quantitation of Ten Urinary Nicotine Metabolites, Including 4-Hydroxy-4-(3-pyridyl) Butanoic Acid, a Product of Nicotine 2'-Oxidation, and CYP2A6 Activity in Japanese Americans, Native Hawaiians, and Whites.

Smoking intensity varies across smokers and is influenced by individual variability in the metabolism of nicotine, the major addictive agent in tobacco. Therefore, lung cancer risk, which varies by racial ethnic group, is influenced by the primary catalyst of nicotine metabolism, cytochrome P450 2A6 (CYP2A6). In smokers, CYP2A6 catalyzes nicotine 5'-oxidation. In vitro, CYP2A6 also catalyzes, to a much lower extent, 2'-oxidation, which leads to the formation of 4-hydroxy-4-(3-pyridyl) butanoic acid (hydroxy acid). The urinary concentration of hydroxy acid has been quantified in only a few small studies of White smokers. To quantitatively assess the importance of nicotine 2'-oxidation in smokers, an LC-MS/MS-based method was developed for the analysis of nicotine and ten metabolites in urine. The concentrations of nicotine and these metabolites were measured in 303 smokers (99 Whites, 99 Native Hawaiians, and 105 Japanese Americans), and the relative metabolism of nicotine by four pathways was determined. Metabolism by these pathways was also compared across quartiles of CYP2A6 activity (measured as the plasma ratio of 3-hydroxycotinine to cotinine). As reported previously and consistent with their average CYP2A6 activity, nicotine 5'-oxidation was highest in Whites and lowest in Japanese Americans. Nicotine N-glucuronidation and N-oxidation increased with decreasing CYP2A6 activity. However, the relative urinary concentration of hydroxy acid (mean, 2.3%; 95% CI, 2.2-2.4%) did not vary by ethnic group or by CYP2A6 activity. In summary, CYP2A6 is not an important catalyst of nicotine 2'-oxidation in smokers, nor does nicotine 2'-oxidation compensate for decreased CYP2A6 activity.

Assessment of exposure and DNA damage from second-hand smoke using potential biomarker in urine: cigarettes and heated tobacco products.

Second-hand smoke exposure is an established cause of several adverse health effects. Tobacco smoke exposure in the environment has been improved by the WHO Framework Convention on Tobacco Control. However, concerns have been raised regarding the health effects of heated tobacco products. Analysis of tobacco smoke biomarkers is critical for assessing the health effects of second-hand tobacco smoke exposure. In this study, nicotine metabolites (nicotine, cotinine, trans-3'-hydroxycotinine) and carcinogenic 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol were analysed in the urine of non-smokers with or without passive exposure to cigarettes and heated tobacco products. In addition, 7-methylguanine and 8-hydroxy-2'-deoxyguanosine were simultaneously measured as DNA damage markers. The results revealed higher levels of urinary nicotine metabolites and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol in participants exposed to second-hand tobacco smoke (both cigarettes and heated tobacco products) at home. In addition, the urinary levels of 7-methylguanine and 8-hydroxy-2'-deoxyguanosine tended to be higher in the second-hand tobacco smoke-exposed group. The urinary levels of nicotine metabolites and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol were high in workplaces with no protection against passive smoking. These biomarkers will be useful for evaluating passive exposure to tobacco products.

A low-cost eco-friendly fast drug extraction (FaDEx) technique for environmental and bio-monitoring of psychoactive drug in urban water and sports-persons’ urine samples

Nicotine is the most prominent psychoactive/addictive chemical substance consumed worldwide among young players in team sports. Moreover, urinary nicotine discharge and nicotine-based products disposal in environmental waters has been unavoidable in recent years. Therefore, sensitive monitoring of nicotine content in environmental waters and human urine samples is essential. In this study, we developed a miniaturized novel green, low-cost, sensitive, in-syringe-based semi-automated fast drug extraction (FaDEx) protocol coupled with gas chromatography-flame ionization detection (GC-FID) for the efficient environmental and bio-monitoring of nicotine in aqueous samples. The FaDEx method consists of two steps; firstly, the target analyte was extracted using dimethyl carbonate (a green solvent) and extraction salts. After that, the extraction solvent was passed automatically through the solid-phase extraction cartridge at a constant flow rate for the cleanup process to achieve the sensitive nicotine analysis by GC-FID. Under optimized experimental conditions, the developed method showed excellent linearity over the concentration ranges between 20–2000 ng mL−1 with a correlation coefficient >0.99. The detection and quantification limits were 4 and 20 ng mL−1, respectively. The presented method was applied to monitor and assess nicotine exposure in sports-persons’ urine and environmental water samples. The method accuracy and precision in terms of relative recovery and relative standard deviation (for triplicate analysis) were 85.4–110.2% and ≤8%, respectively. Finally, the impact of our procedure on the environment from a green analytical chemistry view was assessed using a novel metric system called AGREE, and obtained the greenness score of 0.87, indicating its an efficient alternative green analytical protocol for routine environmental and bio-monitoring of nicotine in environmental and biological samples.

Assessment of the Exposure to Aromatic Amines in Users of Various Tobacco/Nicotine Products.

Aromatic amines such as ortho-toluidine (o-Tol), 2-aminonaphthalene (2-AN), and 4-aminobiphenyl (4-ABP) are human bladder carcinogens and occur at various workplaces, in ambient air, in food products, as well as in tobacco smoke. In a clinical study comprising a period of 74 h under confinement, we investigated the exposure to these three aromatic amines as well as to 3-aminobiphenyl (3-ABP) by measuring them in urine of habitual users of combustible cigarettes (CCs), electronic cigarettes (ECs), heated tobacco products (HTPs), oral tobacco (OT), and nicotine replacement therapy products (NRTs). Non-users (NU) of any tobacco/nicotine products served as (negative) control group. Smokers (CC) exhibited the highest levels for all four aromatic amines measured, significantly elevated compared to NU and non-CC users. Urinary levels in users of EC, HTP, NRT (mostly nicotine gum), and OT (mostly snus) were not significantly different from those in NU. Users of HTP showed slightly elevated urinary excretion levels of o-Tol, 3-ABP, and 4-ABP compared to some other non-CC groups. Dose markers such as daily consumption, urinary nicotine equivalents (Nequ), and plasma cotinine (CotP) were found to be consistently and significantly correlated with the excretion of aromatic amines for smokers (CC) only. Excretion levels of 3- and 4-ABP in smokers were significantly lower in the urine collected overnight compared to that collected during the day, which is just the opposite of what we observed for other biomarkers in this study. The possible reason for this observation is discussed. In conclusion, in contrast to smoking of CCs, the use of ECs, HTPs, nicotine gum, and oral tobacco was not observed to be associated with significant exposure to the aromatic amines o-Tol, 2-AN, 3-ABP, and 4-ABP. The observed slight increase in o-Tol, 3-ABP, and 4-ABP excretions in HTP users has to be verified in larger studies.

Impact of Genetic Variants in the Nicotine Metabolism Pathway on Nicotine Metabolite Levels in Smokers.

Nicotine metabolism is a major factor in nicotine dependence, with approximately 70% to 80% of nicotine metabolized to cotinine in Caucasians. Cotinine formation is catalyzed primarily by CYP2A6, which also converts cotinine to trans-3'-hydroxycotinine (3HC). The goal of the present study was to examine the effects of CYP2A6 deficiency on nicotine metabolism profiles in vivo and the importance of genetic variants in nicotine-metabolizing enzyme genes on urinary nicotine metabolites levels. Urine samples from 722 smokers who participated in the Singapore Chinese Health Study were analyzed using UPLC-MS/MS to detect nicotine and eight of its urinary metabolites, and a total of 58 variants in 12 genes involved in nicotine metabolism were investigated in 475 of these subjects with informative genotyping data. Urine samples stratified by the ratio of 3HC/cotinine exhibited a 7-fold increase in nicotine-N'-oxide, a 6-fold increase in nicotine-Glucuronide (Gluc), and a 5-fold decrease in 3HC-Gluc when comparing the lower versus upper 3HC/cotinine ventiles. Significant (P < 0.0001) associations were observed between functional metabolizing enzyme genotypes and levels of various urinary nicotine metabolites, including CYP2A6 genotype and levels of nicotine, nicotine-Gluc, nicotine-N'-oxide and 3HC, UGT2B10 genotype and levels of cotinine, nicotine-Gluc and cotinine-Gluc, UGT2B17 genotype and levels of 3HC-Gluc, FMO3 genotype and levels of nicotine-N'-oxide, and CYP2B6 genotype and levels of nicotine-N'-oxide and 4-hydroxy-4-(3-pyridyl)-butanoic acid. These data suggest that several pathways are important in nicotine metabolism. Genotype differences in several nicotine-metabolizing enzyme pathways may potentially lead to differences in nicotine dependence and smoking behavior and cessation.

Effect modification by aging on the associations of nicotine exposure with cognitive impairment among Chinese elderly.

Active and passive exposure to tobacco smoke may increase risk of cognitive decline. However, effects of enhanced the aging process on the association of urinary nicotine metabolites with cognitive impairment remain unclear. In this study, 6657 Chinese older adults completed the physical examinations and cognitive tests. We measured urinary nicotine metabolite levels, mitochondrial DNA copy number (mtDNA-CN), and relative telomere length (RTL) and analyzed effects of urinary nicotine metabolites and their interaction with mtDNA-CN or RTL on cognitive impairment by generalized linear models and qg-computation, respectively. Each 1-unit increase in urinary 3-OHCot, 3-OHCotGluc, CotGluc, or NicGluc levels corresponded to a 1.05-, 1.09-, 1.04-, and 0.90-fold increased risk of cognitive impairment. Each 1-quantile increment in the mixture level of 8 nicotine metabolites corresponded to an increment of 1.40- and 1.34-fold risk of cognitive impairment in individuals with longer RTL or low mtDNA-CN. Urinary 3-OHCotGluc and RTL or mtDNA-CN exhibited an additive effect on cognitive impairment in addition to the mixture of 8 nicotine metabolites and mtDNA-CN. The findings suggested that aging process may increase the risk of tobacco-related cognitive impairment.

The interaction effects of secondhand smoke exposure and overweight on the prevalence of hypertension in Chinese coke oven workers and NHANES participants (2013-2016).

The prevalence of hypertension may be affected by environmental pollution and personal behavior. We aimed to evaluate the interaction effects of secondhand smoke exposure and overweight on hypertension. In this cross-sectional study, a total of 627 workers from a coking plant in China and 1011 individuals from the NHANES database in the United States from 2013 to 2016 were selected as the research participants. The concentrations of 11 urinary polycyclic aromatic hydrocarbons (PAHs) metabolites and 3 tobacco metabolites were measured. An interaction effect was tested in the modified Poisson regression models. For smokers among Chinese coke oven workers, the only statistically significant positive association was with hypertension in the highest tertile of nicotine metabolized ratio (NMR) (PR: 1.539, 95% CI: 1.013-2.337). Nonsmoking Chinese workers with 3rd tertile urinary nicotine levels were associated with a 114.8% significantly increased prevalence of hypertension (PR: 2.148, 95% CI: 1.025-4.500) compared to nonsmokers 1st tertile with nicotine levels. Association between tobacco exposure and hypertension is possibly modified by PAHs exposure (PR: 2.335, 95% CI: 0.933-5.841). Nonsmokers in the NHANES database with high urinary nicotine levels were associated with a 17.3% significantly increased prevalence of hypertension (PR: 1.173, 95% CI: 1.028-1.338) compared to those with low nicotine levels. We observed that overweight people with high nicotine levels had a significantly higher likelihood of hypertension than no overweight people with low nicotine levels among nonsmoking Chinese coke oven workers and NHANES participants (PR=4.686, 95% CI: 1.488-14.754; PR=1.251, 95% CI: 1.039-1.506). Tobacco exposure and overweight are important risk factors for hypertension, and secondhand smoke exposure and overweight have an interactive effect on the incidence of hypertension in nonsmoking Chinese coke oven workers and NHANES participants.

A Randomized, Controlled Study to Assess Biomarkers of Exposure in Adult Smokers Switching to Oral Nicotine Products.

This open-label, randomized, controlled, in-clinic, 6-parallel-group study evaluated changes in biomarkers of exposure (BoEs) to select harmful and potentially harmful constituents in adult smokers (N = 213) not planning to quit smoking. Adult smokers were randomized to continue smoking (CS), reduce smoking by 50% and dual use oral tobacco-derived nicotine (OTDN) products (VERVE chews/discs), stop smoking and exclusively use discs or chews, or stop using all tobacco products (NT). The primary objective compared 24-hour urinary total 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL; a biomarker for the carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone) in dual and exclusive use of discs and chews to continue smoking and NT on day 7. NNAL levels on day 7 were significantly lower (P < .05) among dual and exclusive users of discs/chews compared to continue smoking; median percent reductions were ≈30% and ≈73%, respectively. NNAL levels were not significantly different between those who used discs/chews and the NT group. Many of the additional secondary biomarkers of exposure were significantly lower in dual users (10/19) and exclusive users of discs/chews (17/19) compared to the continue smoking group. Overall, reductions in secondary biomarkers of exposure were greater in exclusive users than dual users. The 24-hour urinary nicotine equivalents were significantly lower (P < .05) among exclusive users of discs/chews compared to continue smoking. The discs/chews appeared to be well tolerated. These results demonstrate that while switching completely to discs/chews substantially reduces exposure to select harmful and potentially harmful constituents, dual use with 50% reduction in cigarette consumption also reduces exposure. oral tobacco-derived nicotine products like discs/chews may present a harm reduction opportunity for adult smokers, particularly those not intending to quit smoking.