Search Results (51)

Background: This study was conducted to identify genetic risk variants associated with nicotine addiction in the CHRNA5, HTR2A, DRD4, and CYP2A6 genes among electronic cigarette users who also smoke combustible cigarettes (dual users), and to assess potential genotoxic and cytotoxic damage in the oral mucosal cells of the study population. Methods: We included dual e-cig users (ECIG, n = 70), combustible cigarette smokers (CCU, n = 24), and non-smokers and non-e-cig users (NS, n = 110). Genetic variants in CHRNA5, HTR2A, DRD4, and CYP2A6 were genotyped. Micronucleus analysis was performed on oral mucosal cells to detect cellular abnormalities. Results: The ECIG group demonstrated greater nicotine addiction on the Fagerström Test for Nicotine Dependence (FTND, 5.5 vs. 1, p = 0.023). Salivary cotinine levels were significantly higher in the ECIG group compared to the CCU group (39 vs. 12 ng/mL, p < 0.001). The carriers of the A allele (rs16969968/CHRNA5) had higher FTND scores, carriers of the C allele (rs1800955/DRD4) used electronic cigarettes more frequently each day, and carriers of the T allele (rs4105144/CYP2A6) started using nicotine products at a younger age. The number of micronuclei and cellular abnormalities in the oral mucosa was higher in the ECIG and CCU groups compared to the NS group. Conclusions: Salivary cotinine levels and FTND are higher in dual e-cigarette users than in combustible cigarette users. Dual users exhibit risk alleles in the CHRNA5, DRD4, and CYP2A6 genes, which are associated with traits linked to increased nicotine addiction. Dual e-cigarette use poses comparable genotoxic risks to combustible smoking. Full article

Background/Objectives: Oral squamous cell carcinoma (OSCC) and oral potentially malignant disorders (OPMDs) remain major clinical challenges due to late diagnosis and limited prognostic markers. This study evaluated salivary interleukin-6 (IL-6) and cotinine as potential biomarkers for oral epithelial transformation and exposure to risk factors. Methods: From 267 individuals with histopathologically confirmed OPMDs or OSCC, 47 patients met the inclusion criteria and were enrolled (18 OPMDs, 29 OSCC). A control group comprised 40 individuals without oral mucosal pathology. Unstimulated saliva samples were collected and analyzed for IL-6 and cotinine concentrations. Biomarker levels were compared among groups and evaluated in relation to smoking exposure, alcohol use, and clinicopathological parameters. Results: Salivary IL-6 and cotinine levels differed significantly among groups (p < 0.05), with the highest concentrations observed in OSCC patients, intermediate levels in OPMDs, and the lowest levels in controls. Cotinine levels were significantly higher in smokers and individuals with greater tobacco exposure in both study groups, whereas IL-6 concentrations were not significantly associated with smoking or alcohol consumption. No correlation between IL-6 and cotinine was found in OPMDs or OSCC; however, a moderate negative correlation was observed in controls. Conclusions: Salivary IL-6 and cotinine demonstrate potential as complementary, non-invasive biomarkers for assessing oral epithelial transformation and tobacco exposure. Their combined evaluation may support risk stratification and early detection in patients with OPMDs. Full article

Maternal Smoking During Pregnancy (MSDP) remains a major source of fetal toxicant exposure. We applied adductomics to profile reactive adducts at the human serum albumin cysteine-34 (HSA-Cys³⁴) locus, which integrates longer-term exposures. HSA-Cys³⁴ adducts formed by acrylonitrile and ethylene oxide, two tobacco-related toxicants previously linked to smoking in adults, were quantified and compared with cotinine and MSDP status. Their relationships with other reactive adducts were also examined. Neonatal dried blood spots (DBS) from 110 children were analyzed. Cotinine and 55 Cys³⁴ adducts were measured by Liquid Chromatography–Tandem Mass Spectrometry (LC-MS/MS). Associations were evaluated using linear regression, chi-square tests, and principal component analysis. Eighteen adducts differed significantly by MSDP status after Bonferroni correction (p ≤ 9.1 × 10⁻⁴). S-acrylonitrile was markedly elevated in exposed newborns, including those whose mothers reported smoking cessation after early pregnancy (p < 0.001). S-acrylonitrile correlated with 31 adducts related to oxidative stress and thiol metabolism, whereas cotinine correlated with eight. S-ethylene oxide, though detectable in DBS, showed no consistent association with MSDP. Adductomics analysis of newborn DBS sensitively captures molecular signatures of prenatal tobacco exposure and related oxidative stress. Acrylonitrile adducts appear to better reflect cumulative MSDP exposure than cotinine, highlighting the utility of adductomics for improved exposure assessment and mechanistic insight. Full article

Nicotine exposure from e-cigarette use remains a growing public health concern, necessitating reliable biomarkers and analytical approaches for long-term exposure assessment. This study aimed to investigate the feasibility of detecting and classifying cotinine, the primary metabolite of nicotine, in fingernails of e-cigarette users using Fourier transform infrared (FTIR) spectroscopy coupled with chemometric analysis. Fingernail samples were collected and extracted from 30 e-cigarette users and 30 non-smokers. Infrared spectra were acquired in attenuated total reflectance mode and analysed using principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) for classification and prediction. Distinct spectral features associated with cotinine were observed in smoker samples, particularly an absorption band near 1277 cm⁻¹ corresponding to C–N stretching vibrations. Quantitative analysis revealed significantly higher cotinine concentrations in smokers compared with non-smokers (p < 0.05, Mann–Whitney U test). Chemometric modelling achieved complete discrimination between groups, with the PLS-DA model demonstrating excellent predictive performance and an area under the receiver operating characteristic (ROC) curve of 1.0. These findings indicate that FTIR spectroscopy combined with chemometric tools provides a rapid and effective approach for cotinine detection in fingernails, supporting its potential application in nicotine exposure assessment. Full article

Tobacco smoke exposure not only increases the risks of lung cancer and cardiovascular disease, but can be a stressor contributing to mental illness. It is important to clarify the relationship between chronic tobacco smoke exposure and mental stress from the perspective of disease prevention. We developed a simple and highly sensitive method for simultaneously analyzing nine biomarkers: nicotine and cotinine (tobacco smoke exposure markers); cortisol, testosterone, and dehydroepiandrosterone (stress-related markers); and serotonin, melatonin, dopamine, and oxytocin (relaxation-related markers). Biomarkers were extracted and concentrated by in-tube solid-phase microextraction with a Supel-Q PLOT capillary, followed by separation and detection within 7 min using liquid chromatography–tandem mass spectrometry on a Discovery HS F5 column. Calibration curves using stable isotope-labeled internal standards showed good linearity (0.005–100 ng mL⁻¹) with detection limits of 0.09–13.5 pg mL⁻¹. Intra-day and inter-day precision had relative standard deviations below 7.2% and 15.5% (n = 6), respectively, with recovery rates of 84.0–108.8%. The automated method requires only ultrafiltration of hair methanol extract, enabling non-invasive pg-level analysis using just a few milligrams of hair. Hair analysis reflects an association between chronic tobacco smoke exposure and stress. This method is effective for analyzing the relationship between long-term tobacco smoke exposure and chronic stress. Full article

The increasing use of electronic cigarettes (e-cigarettes) highlights the need for accessible and reliable biomarkers to assess nicotine exposure. Fingernails represent a non-invasive and stable keratin matrix capable of capturing the long-term incorporation of xenobiotics such as cotinine, the primary metabolite of nicotine. This study aimed to optimise cotinine extraction from fingernails using Response Surface Methodology (RSM) with a central composite design prior to quantification by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. Three extraction variables were evaluated: NaOH concentration, extraction temperature, and extraction time. Numerical optimisation identified the optimal conditions as 3.74 M NaOH, 50 °C, and 40 min, yielding a predicted recovery of 84.06% with a high desirability value of 0.973. The calibration curve demonstrated excellent linearity (R² = 0.9998), with a limit of detection of 14.5 µg kg⁻¹ and a limit of quantification of 43.8 µg kg⁻¹. The RSM model exhibited strong predictive performance, with an R² of 0.9990, an adjusted R² of 0.9982, and a predicted R² of 0.9958, supported by a non-significant lack of fit and robust residual diagnostics. Application of the optimised protocol to real fingernail samples successfully differentiated e-cigarette smokers from non-smokers based on characteristic cotinine-associated FTIR spectral features and quantitative measurements, demonstrating the practical utility of the proposed method. Overall, this study establishes a rapid, chromatography-free, and cost-effective analytical approach for monitoring long-term nicotine exposure using keratin-based matrices. Full article

Shallow lakes are highly vulnerable to pollution due to their small water volume. Those that receive effluent from the drainfields of onsite wastewater treatment systems (septic tanks) may contain pharmaceuticals and personal care products (PPCPs) that escaped removal during treatment. This study examined the effects of seasonal rainfall variability on the assemblages and concentrations of fourteen PPCPs in two shallow lakes in West–Central Florida, USA: one surrounded by residents equipped with septic tanks and the other located within a nature preserve. Water samples were collected weekly during an 18-week interval from April to August 2021. Liquid chromatography–mass spectrometry analyses revealed the omnipresence of five PPCPs: theophylline, caffeine, cotinine, DEET, and testosterone, although acetaminophen, ibuprofen, and sulfamethoxazole were also common. Of all the PPCPs detected, theophylline, DEET, and acetaminophen concentrations were higher during the wet season in the septic tank-influenced lake, while caffeine, cotinine, and testosterone concentrations decreased. In the lake located in the nature preserve, theophylline, caffeine, and acetaminophen levels increased in the wet season. In contrast, cotinine, DEET, and testosterone levels decreased. Overall, more compounds were detected during the wet season, with highly hydrophobic PPCPs (fluoxetine, atorvastatin, and octocrylene) only present during this period. Full article

Although the use of electronic nicotine delivery systems (ENDS) among youth has declined since its peak in 2018, it remains popular among young adults. Despite its popularity, research on the health effects of secondhand exposure to ENDS remains limited. Silicone wristbands offer a simple, cost-effective method for measuring nicotine exposure. The study employed a quasi-experimental design and recruited six dyads consisting of ENDS users and non-users. Over three consecutive months, all participants wore silicone wristbands for one week at a time to assess nicotine exposure. ENDS users had a higher overall median nicotine concentration in their silicone wristbands (423.2 ng/g, IQR: 199.2–669.1) compared to non-users (17.2 ng/g, IQR: 6.5–128.0). This trend was consistent across all time points. Statistically significant differences between ENDS users and non-users were observed during months 1 and 2 (p-values = 0.0303 and 0.0411, respectively), but not during month 3 (p-value = 0.2468). Similar trends were observed in urinary cotinine levels, with higher medians among ENDS users (1013.0 ng/mL, IQL: 442.0–1490.0) compared to non-users (1.3 ng/mL, IQL: 1.0–1.4). A significant correlation was found between urinary cotinine and wristband nicotine levels only in non-users (r = 0.69, p-value = 0.0017). Silicone wristbands worn by non-users can detect secondhand nicotine exposure and are significantly correlated with urinary cotinine. Full article

Background and Objectives: Tobacco use and exposure to tobacco products remain a major public health challenge, even among athletes. This study aimed to evaluate tobacco use and second-hand smoke exposure in athletes through urinary cotinine levels and exhaled air carbon monoxide (CO) measurements. Materials and Methods: This cross-sectional study included licensed athletes who visited the sports medicine outpatient clinic of a tertiary hospital. Participants completed an electronic questionnaire on smoking habits and second-hand smoke exposure. Urine samples were analysed for cotinine levels, while CO levels were measured in exhaled breath. Results: A total of 421 athletes participated (57.8% male, median age: 18 years). Tobacco use was reported by 29.9% (n = 126) of participants. Median urinary cotinine levels were 22.9 ng/mL among daily tobacco users and 17.4 ng/mL among athletes exposed daily to second-hand smoke, with a statistically significant difference between exposure levels (p < 0.05). The optimal cut-off value for detecting second-hand smoke exposure was identified as 12.5 ng/mL. Median exhaled air CO levels were 5 ppm in daily tobacco users. Conclusions: This study demonstrates that tobacco use prevalence among athletes mirrors Türkiye’s national rates. Despite legal measures to curb tobacco use, direct use and second-hand smoke exposure remain pressing issues among athletes. Full article

Tobacco smoke has numerous adverse effects on both human and animal health, including impaired reproductive function. Recent research has explored environmental exposure in dogs, investigating various biological matrices. However, no data are currently available on the presence of cotinine, a nicotine metabolite, in the canine ejaculate. This study aimed to evaluate the detectability of cotinine in the semen of dogs living with smoking owners. Additionally, seminal cotinine concentrations were correlated with those in serum and hair. To further examine the potential impact of smoking on canine fertility, the relationships between seminal cotinine, total sperm concentration, and antioxidant activity in plasma and semen were analyzed in exposed and non-exposed dogs. This study is the first to demonstrate the presence of cotinine in canine ejaculate and its correlation with blood and hair concentrations. While the potential toxic effect of cotinine on seminal parameters and male fertility in dogs requires further investigation, it is crucial to raise awareness among pet owners about the risks associated with domestic smoking for their animals. Full article

Passive smoking from environmental tobacco smoke not only increases the risk of lung cancer and cardiovascular disease but may also be a stressor triggering neuropsychiatric and other disorders. To prevent these diseases, understanding the relationship between passive smoking and stress is vital. In this study, we developed a simple and sensitive method to simultaneously measure nicotine (Nic) and cotinine (Cot) as tobacco smoke exposure biomarkers, and cortisol (CRT), serotonin (5-HT), melatonin (MEL), dopamine (DA), and oxytocin (OXT) as stress-related biomarkers. These were extracted and concentrated from saliva by in-tube solid-phase microextraction (IT-SPME) using a Supel-Q PLOT capillary as the extraction device, then separated and detected within 6 min by liquid chromatography–tandem mass spectrometry (LC−MS/MS) using a Kinetex Biphenyl column (Phenomenex Inc., Torrance, CA, USA). Limits of detection (S/N = 3) for Nic, Cot, CRT, 5-HT, MEL, DA, and OXT were 0.22, 0.12, 0.78, 0.39, 0.45, 1.4, and 3.7 pg mL⁻¹, respectively, with linearity of calibration curves in the range of 0.01–25 ng mL⁻¹ using stable isotope-labeled internal standards. Intra- and inter-day reproducibilities were under 7.9% and 14.6% (n = 5) relative standard deviations, and compound recoveries in spiked saliva samples ranged from 82.1 to 106.6%. In thirty nonsmokers, Nic contents positively correlated with CRT contents (R² = 0.5264, n = 30), while no significant correlation was found with other biomarkers. The standard deviation of intervals between normal beats as the standard measure of heart rate variability analysis negatively correlated with CRT contents (R² = 0.5041, n = 30). After passive smoke exposure, Nic levels transiently increased, Cot and CRT levels rose over time, and 5-HT, DA, and OXT levels decreased. These results indicate tobacco smoke exposure acts as a stressor in nonsmokers. Full article

Objective: We conducted a study to determine if antenatally collected maternal urine cotinine (a metabolite of nicotine) measurements can be used to assess the neonatal impact of nicotine exposure during pregnancy. This was a prospective longitudinal cohort of mother–infant dyads. Only term singleton pregnancies were included. The primary outcome measure was the correlation between maternal urine cotinine and infant birth weight. Methods: We analysed data from 238 mother–neonate dyads. Smoking habits were recorded during routine prenatal check-ups and urine samples were collected to measure cotinine and creatinine levels. Results: Urine cotinine was detected in 50.4% (120/238) of women from the whole cohort, but only 16% (38/238) self-reported as smokers (chi-square 39.7, p < 0.0001), and these women had significantly smaller babies (p = 0.010). There was a significant negative correlation between maternal urine cotinine and birth weight (Spearman’s coefficient = −0.0226, p = 0.013). Female babies born to women with nicotine in their urine were significantly smaller (p = 0.001). Conclusions: Infant birth weight significantly reduced in mothers with exposure to nicotine during pregnancy. The number of women exposed to nicotine during late pregnancy (measured in urine) was markedly higher than self-reported and national smoking percentages, suggesting an urgent need for an improvement in medical record reporting on smoking habits to better assess neonatal outcomes. Full article

(1) Background: Volatile organic compounds (VOCs) are indoor pollutants absorbed by inhalation. The association of several VOCs with lung function in children and adolescents is unknown. (2) Methods: We analyzed 505 participants, 6–17-year-olds from the 2011–2012 National Health and Nutrition Examination Survey. Multiple linear regression models were fitted to estimate the associations of VOC metabolites with spirometry outcomes adjusting for covariates. (3) Results: Urinary metabolites of xylene, acrylamide, acrolein, 1,3-butadiene, cyanide, toluene, 1-bromopropane, acrylonitrile, propylene oxide, styrene, ethylbenzene, and crotonaldehyde were all detected in ≥64.5% of participants. Forced expiratory volume in 1 s (FEV₁) % predicted was lower in participants with higher levels of metabolites of acrylamide (β: −7.95, 95% CI: −13.69, −2.21) and styrene (β: −6.33, 95% CI: −11.60, −1.07), whereas the FEV₁ to forced vital capacity (FVC) ratio % was lower in children with higher propylene oxide metabolite levels (β: −2.05, 95% CI: −3.49, −0.61). FEV₁ % predicted was lower with higher crotonaldehyde metabolite levels only in overweight/obese participants (β: −15.42, 95% CI: −26.76, −4.08) (P_interaction < 0.001) and with higher 1-bromopropane metabolite levels only in those with serum cotinine > 1 ng/mL (β: −6.26, 95% CI: −9.69, −2.82) (P_interaction < 0.001). (4) Conclusions: We found novel associations of metabolites for acrylamide, propylene oxide, styrene, 1-bromopropane and crotonaldehyde with lower lung function in children and adolescents. Full article

There are known health concerns linked to prenatal tobacco and cannabis exposures. This study aims to objectively determine the level of exposure to tobacco and cannabis in pregnant individuals from six race/ethnicity groups (Black, Hispanic, Asian Indian, Native American, Vietnamese, and White) in the first three years following legalization of recreational marijuana use in 2018 in California. We used a cross-sectional sample of prenatal screening program participants (2018–2020) from southern and central California (N = 925). Exposures were estimated by a lab analysis of cotinine (tobacco) and 11-hydroxy-Δ9-tetrahydrocannabinol (OH-THC, cannabis) in banked serum. Disparities in tobacco exposure were evident, with Black subjects experiencing the highest smoking rate (16%) followed by Native American (10%) and White (8%) subjects, and ≤2% among Hispanic, Asian Indian, and Vietnamese subjects. Environmental tobacco exposure generally showed a similar pattern of exposure to tobacco smoking across race/ethnicity groups. Cannabis detection ranged from 5% among Hispanic subjects to 12% and 13% among White and Black subjects, respectively, and was higher among tobacco users and those exposed to environmental tobacco smoke than those with no cotinine detected. Tobacco and cannabis exposure were generally greatest in younger subjects and those with indices of a lower economic status; however, among Black subjects, cannabis exposure was greatest in older subjects and those with a higher socioeconomic status. Race/ethnicity, age, and socioeconomic factors can inform targeting of high-exposure groups for intervention. Full article

Torque Teno Virus (TTV) is a non-pathogenic virus that is highly prevalent among kidney transplant recipients (KTRs). Its circulating load is associated with an immunological status in KTR and is considered a promising tool for guiding immunosuppression. To allow for optimal guidance, it is important to identify other determinants of TTV load. We aimed to investigate the potential association of smoking and alcohol intake with TTV load. For this cross-sectional study, serum TTV load was measured using PCR in stable kidney transplant recipients at ≥1 year after transplantation, and smoking status and alcohol intake were assessed through questionnaires and measurements of urinary cotinine and ethyl glucuronide. A total of 666 KTRs were included (57% male). A total of 549 KTR (82%) had a detectable TTV load (3.1 ± 1.5 log₁₀ copies/mL). In KTR with a detectable TTV load, cyclosporin and tacrolimus use were positively associated with TTV load (St. β = 0.46, p < 0.001 and St. β = 0.66, p < 0.001, respectively), independently of adjustment for potential confounders. Current smoking and alcohol intake of >20 g/day were negatively associated with TTV load (St. β = −0.40, p = 0.004 and St. β = −0.33, p = 0.009, respectively), independently of each other and of adjustment for age, sex, kidney function, time since transplantation and calcineurin inhibitor use. This strong association of smoking and alcohol intake with TTV suggests a need to account for the smoking status and alcohol intake when applying TTV guided immunosuppression in KTR. Full article