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130 result(s) for "Naphthalenes - urine"
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Urinary Biomarkers of Polycyclic Aromatic Hydrocarbons Are Associated with Cardiometabolic Health Risk
Polycyclic aromatic hydrocarbons (PAH) are both man-made and naturally occurring environmental pollutants that may be related to cardiometabolic health risk. To determine whether PAH is associated with obesity in the adult population and to examine whether urinary concentrations of PAH metabolites are associated with differences in how obesity relates to 3 or more risk factors for the metabolic syndrome (3RFMetS), type 2 diabetes (T2D), hypertension, and dyslipidemia. A total of 4765 adult participants from the 2001-2008 National Health and Nutrition Examination Survey were examined. The association between 8 urinary hydroxylated PAH metabolites, obesity, and health were examined using weighted logistic regressions adjusting for age, sex, ethnicity, PIR, smoking status, and urinary creatinine. There was a positive dose-dependent association between obesity and 2-phenanthrene quintiles (P trend <0.0001). Contrarily, higher quintiles of 1-naphthalene were associated with lower risk of obesity (P trend = 0.0004). For a given BMI, those in the highest quintile of 2-naphthalene, 2-fluorene, 3-fluorene and 2-phenanthrene had a 66-80% greater likelihood of 3RFMetS (P≤0.05) compared to low levels. Higher quintiles of 1-naphthalene, 2-naphthalene, 2-phenanthrene and 1-pyrene were associated with a 78-124% greater likelihood of T2D (P≤0.05) compared to low levels while high 1-naphthalene, 2-naphthalene, 2-fluorene, 3-fluorene and 2-phenanthrene were associated with a 38-68% greater likelihood of dyslipidemia (P≤0.05) compared to lower levels. Finally, 2-naphthalene and 2-phenanthrene were positively associated with hypertension (P trend = 0.008 and P trend = 0.02 respectively). PAH is related to obesity and the expression of a number of obesity-related cardiometabolic health risk factors. Future research is needed to bring to light the mechanistic pathways related to these findings.
Renal excretion of 1,2-dihydroxynaphthalene (DHN) in firefighting instructors after exposure to polycyclic aromatic hydrocarbons (PAHs) during live fire training
Exposure of firefighting instructors to polycyclic aromatic hydrocarbons (PAHs) such as naphthalene is unavoidable during live fire training. The study aimed to investigate naphthalene uptake by measuring the urinary excretion of the naphthalene metabolite 1,2-dihydroxynaphthalene (DHN), to describe the DHN elimination kinetics and to evaluate the results by comparison to further biomarkers of PAH exposure. N = 6 male non-smoking firefighting instructors completed five training sessions each in a residential fire simulation unit under respiratory protection. All participants provided two urine samples before and another seven samples within an 18-h-interval after each session. DHN was detected by gas chromatography/tandem mass spectrometry (GC–MS/MS) in all samples (n = 237) with median concentrations ranging from 3.3 µg/g crea. (range 0.9–10.2) before exposure to 134.2 µg/g crea. (43.4–380.4) post exposure. Maximum elimination found 3.3 h (median) after onset of exposure decreased with a mean half-life of 6.6 h to 27.1 µg/g crea. (15.7–139.5) 18 h after training. DHN sensitively indicated a presumed dermal naphthalene intake during training, showing similar elimination kinetics like other naphthalene metabolites. Internal exposure of the participants transiently exceeded exposures determined for non-smokers in the general population, but was lower than at other workplaces with PAH exposure. Despite limited uptake, accumulation is possible with daily exposure.
Hair and urinary 2-hydroxynaphthalene levels in the people living in a region with frequent oil pipeline incidents in Iran: Health risk assessment
Oil spills from pipeline accidents can have long-lasting health effects on residents of polluted regions. Assessing the potential health risk of these accidents is crucial for effective environmental health management. This study analyzed the concentration of 2-OHNAP in urine and hair as biomarkers of PAHs exposure among the people living in a region with frequent oil pipeline incident in Iran. Fifty pairs of hair and urine samples were collected from residents along with demographic information and dietary habits via a questionnaire. The concentration of 2-OHNAP was analyzed using high performance liquid chromatography coupled with fluorescence detector (HPLC-FLD). 2-OHNAP was detected in 100% of urine and 88% of hair samples. The mean concentration of 2-OHNAP in urine was 16.65 ± 21.98 μg/g creatinine and in hair was 8.16±7.62 ng/g dry weight (dw). However, there was no significant correlations between the levels of 2-OHNAP in urine and hair. The mean values of HQ and CR were below 1 and 10 −6 , respectively. Moreover, some simulated health risk indices were near the threshold levels, and the carcinogenic risk above 70% of the simulated CRs was above 10 −6 as well. Therefore, the health risk attributed to the exposure to the parent compound of 2-OHNAP in the study area is currently acceptable, but it is not negligible and may be worsened in the future. This study provides a valuable scientific information for regional decision makers and stakeholders about human health programs and identification of environmental health priorities.
Nontargeted SWATH acquisition for identifying 47 synthetic cannabinoid metabolites in human urine by liquid chromatography-high-resolution tandem mass spectrometry
Clandestine laboratories constantly produce new synthetic cannabinoids to circumvent legislative scheduling efforts, challenging and complicating toxicological analysis. Sundstrom et al. (Anal Bioanal Chem 405(26):8463–8474, [ 9 ]) and Kronstrand et al. (Anal Bioanal Chem 406(15):3599–3609, [ 10 ]) published nontargeted liquid chromatography, high-resolution, quadrupole/time-of-flight mass spectrometric (LC-QTOF) assays with validated detection of 18 and 38 urinary synthetic cannabinoid metabolites, respectively. We developed and validated a LC-QTOF urine method for simultaneously identifying the most current 47 synthetic cannabinoid metabolites from 21 synthetic cannabinoid families (5-fluoro AB-PINACA, 5-fluoro-AKB48, 5-fluoro PB-22, AB-PINACA, ADB-PINACA, AKB48, AM2201, JWH-018, JWH-019, JWH-073, JWH-081, JWH-122, JWH-200, JWH-210, JWH-250, JWH-398, MAM2201, PB-22, RCS-4, UR-144, and XLR11). β-Glucuronidase-hydrolyzed urine was extracted with 1-mL Biotage SLE+ columns. Specimens were reconstituted in 150-μL mobile phase consisting of 80 % A (0.1 % formic acid in water) and 20 % B (0.1 % formic acid in acetonitrile). Fifty microliters was injected, and SWATH™ MS data were acquired in positive electrospray mode. The LC-QTOF instrument consisted of a Shimadzu UFLCxr system and an ABSciex 5600+ TripleTOF® mass spectrometer. Gradient chromatographic separation was achieved with a Restek Ultra Biphenyl column with a 0.5-mL/min flow rate and an overall run time of 15 min. Identification criteria included molecular ion mass error, isotopic profiles, retention time, and library fit criteria. Limits of detection were 0.25–5 μg/L ( N  = 10 unique fortified urine samples), except for two PB-22 metabolites with limits of 10 and 20 μg/L. Extraction efficiencies and matrix effects ( N  = 10) were 55–104 and −65–107 %, respectively. We present a highly useful novel LC-QTOF method for simultaneously confirming 47 synthetic cannabinoid metabolites in human urine. Graphical Abstract SWATH acquisition MS experiment
Detection of JWH-018 metabolites in smoking mixture post-administration urine
Smoking mixtures containing the cannabimimetic indoles may still be available over-the-counter in several countries. Due to the high affinity of these compounds to the cannabinoid receptors, their effective dose is lower than that of the marijuana products resulting in a low concentration of the excreted metabolites accompanied by a higher psychoactive potency. Up to now the in vivo metabolism of the cannabimimetic indoles seems to be insufficiently investigated and no data have been published on an assay of JWH-018 in urine. In this publication the urinary metabolites of JWH-018 are reported. Using gas and liquid chromatography combined with tandem mass spectrometry two main monohydroxylated metabolites were identified in the forensic urine samples. Based on the differences in their electron ionization MS/MS spectra it is supposed that one is formed by hydroxylation of the indole ring whilst the other by hydroxylation of the N-alkyl chain. The main metabolites are almost completely glucuroconjugated, whereas minor ones ( N-despentyl hydroxy-, carboxy-, dihydroxy-, and reduced di- and trihydroxy metabolites) were also present in the free fraction. The parent compound was not detected in urine.
High-resolution mass spectrometric determination of the synthetic cannabinoids MAM-2201, AM-2201, AM-2232, and their metabolites in postmortem plasma and urine by LC/Q-TOFMS
High-resolution mass spectrometry and accurate mass measurement by liquid chromatography/quadrupole-time of flight mass spectrometry (LC/Q-TOFMS) was applied to postmortem plasma and urine specimens from an autopsy of a fatal case involving synthetic cannabinoid use, resulting in the detection of three synthetic cannabinoids: MAM-2201, AM-1220, and AM-2232. We searched for their metabolites existing in postmortem plasma or urine by LC/Q-TOFMS and were able to detect N -dealkylated metabolites, defluorinated and further oxidized metabolites of MAM-2201, and some hydroxylated metabolites. Postmortem plasma concentrations of the parent drugs, N -dealkylated metabolites, and fluorinated and further oxidized metabolites of MAM-2201 were measured, and quantitation results revealed site differences between heart and femoral postmortem plasma concentrations of parent drugs and some metabolites, suggesting postmortem redistribution of the synthetic cannabinoids and their metabolites. Quantitation results suggest that defluorination is a major metabolic pathway for MAM-2201, and N -dealkylation is a common but minor pathway for the naphthoylindole-type synthetic cannabinoids in human.
A community study of the effect of polycyclic aromatic hydrocarbon metabolites on heart rate variability based on the Framingham risk score
Objectives To investigate the effects of the urinary metabolite profiles of background exposure to the atmospheric pollutants polycyclic aromatic hydrocarbon (PAH) and Framingham risk score (FRS), which assesses an individual's cardiovascular disease risk, on heart rate variability (HRV). Methods The study conducted from April to May 2011 in Wuhan, China, included 1978 adult residents with completed questionnaires, physical examinations, blood and urine samples, and 5-min HRV indices (including SD of all normal to normal intervals (SDNN), root mean square successive difference (rMSSD), low frequency (LF), high frequency (HF) and their ratio (LF/HF), and total power) obtained from 3-channel Holter monitor. 12 urinary PAH metabolites were measured by gas chromatography–mass spectrometry. FRS was calculated by age, sex, lipid profiles, blood pressure, diabetes and smoking status. Linear regression models were constructed after adjusting for potential confounders. Results Elevated total concentration of hydroxynaphthalene (ΣOHNa) was significantly associated, in a dose–responsive manner, with decreased SDNN and LF/HF (ptrend=0.014 and 0.007, respectively); elevated total concentration of hydroxyfluorene (ΣOHFlu) was significantly associated with reduced SDNN, LF and LF/HF (ptrend=0.027, 0.003, and <0.0001, respectively); and elevated total concentration of all PAH metabolites (ΣOH-PAHs) was associated with decreased LF and LF/HF (ptrend=0.005 and <0.0001, respectively). Moreover, increasing quartiles of FRS were significantly associated with decreased HRV indices, except LF/HF (all ptrend<0.0001). Interestingly, individuals in low-risk subgroups had greater decreases in SDNN, LF and LF/HF in relation to ΣOH-PAHs, ΣOHNa and ΣOHFlu than those in high-risk subgroups (all p<0.05). Conclusions Environmental PAH exposure may differentially affect HRV based on individual coronary risk profiles.
Monitoring of urinary metabolites of JWH-018 and JWH-073 in legal cases
Due to their cannabis-like effects, synthetic cannabinoids have attracted much public attention since 2008. Thus, elucidation of the metabolic pattern and the detection of the intake of these drugs have been of major concern. In order to suggest appropriate urinary biomarkers to prove JWH-018 or JWH-073 intake, we selected the major metabolites of JWH-018 and JWH-073, namely (ω)-, (ω-1)-hydroxy, carboxy and 6-hydroxyindole metabolites, and validated a method for the quantification of these metabolites using solid-phase extraction based on LC–MS/MS analysis. Authentic urine specimens obtained from drug offenders were screened via a synthetic cannabinoid ELISA kit and were analyzed by LC–MS/MS for confirmation. Twenty-one out of a total of 52 samples (40%) were found positive for at least one metabolite of JWH-018 or JWH-073. N-pentyl hydroxy metabolites of JWH-018 and carboxy metabolites of JWH-018 and JWH-073 were detected in all positive samples. However, the rest of the metabolites were either not detected or only a small amount of them were found. A considerable variation was observed in the concentration ratio of (ω) and (ω-1)-hydroxy metabolites of JWH-018. Based on the results, it may have some pitfalls to determine the ingestion of specific synthetic cannabinoids by detecting a few metabolites, considering the continuous emergence of structurally related synthetic cannabinoids. Thus, use of synthetic cannabinoids should be proven carefully through comprehensive investigation of analytical results of biological specimens.
Validation and application of an UPLC–MS/MS method for the quantification of synthetic cannabinoids in urine samples and analysis of seized materials from the Portuguese market
•Synthetic cannabinoids analysis in urine samples through an UPLC–MS/MS method.•The method shows small run time, high sensitivity, very good precision and accuracy.•Allows the simultaneous analysis of THC, THC-COOH and 11-OH-THC.•Analysis of 17 seized materials from the Portuguese market. An UPLC–MS/MS method using ESI+ionization and MRM was developed and fully validated according to international guidelines for the qualitative and quantitative analysis of nine synthetic cannabinoids and/or their metabolites in urine samples (1mL). Prior to extraction the samples were subjected to an enzymatic hydrolysis using β-glucuronidase followed by a SPE procedure using Oasis® HLB 3cc (60mg) columns. The chromatographic separation was performed with an Acquity UPLC® HSS T3 (50mm×2.1mm i.d., 1.8μm) reversed-phase column using a gradient with methanol–ammonium formate 2mM (0.1% formic acid) and with a run time of 9.5min. The method was validated in terms of selectivity, capacity of identification, limits of detection (0.01–0.5ng/mL) and quantification (0.05–0.5ng/mL), recovery (58–105%), carryover, matrix effect, linearity (0.05–50ng/mL), intra-assay precision, inter-assay accuracy and precision (CV<20%). The method was applied to 80 authentic samples, five of them (6.2%) were confirmed or suspected to be positive for the metabolites JWH-018 N-hydroxypentyl and JWH-018 N-pentanoic acid of JWH-018 and for the metabolite JWH-122 N-(5-hydroxypentyl) of JWH-122, and three of them in association with THC and/or THCCOOH (substances included in the method, together with the 11-OH-THC). Additionally, 17 spice products were analyzed, for which were confirmed the presence of the following substances: AM-2201, JWH-018, JWH-022 JWH-073, JWH-122, JWH-203, JWH-210, JWH-250, HU-210 and RCS-4, according to the comparison with authentic reference material and published data. The analytical method developed allowed the analysis of synthetic cannabinoids and the notification of the first cases in Portugal.
UHPLC-HRMS and GC-MS Screening of a Selection of Synthetic Cannabinoids and Metabolites in Urine of Consumers
Background and Objectives: The use of synthetic cannabinoids has increased around the world. As a result, the implementation of accurate analysis in human biological matrices is relevant and fundamental. Two different analytical technologies, ultra-high-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) and high-sensitivity gas chromatography-mass spectrometry (GC-MS) were used for the determination of three synthetic cannabinoids JWH-122, JWH 210, UR-144 and their metabolites in urine of consumers. Materials and Methods: Sample preparation included an initial hydrolysis with β-glucuronidase and liquid-liquid extraction. The UHPLC-HRMS method included a Kinetex 2.6 u Biphenyl 100A (100 × 2.1 mm, 2.6 μm) (Phenomenex, Italy) column with a gradient mobile phase consisting of mobile phase A (ammonium formate 2mM in water, 0.1% formic acid) and mobile phase B (ammonium formate 2mM in methanol/acetonitrile 50:50 (v/v), 0.1% formic acid) and a full-scan data-dependent MS2 (ddMS2) mode was used (mass range 100–1000 m/z). The GC-MS method employed an ultra-Inert Intuvo GC column (HP-5MS UI, 30 m × 250 µm i.d, film thickness 0.25 µm; Agilent Technologies, Santa Clara, CA, USA) and electron-impact (EI) mass spectra were recorded in total ion monitoring mode (scan range 40–550 m/z). Results: Both methods have been successfully used for screening of parent synthetic cannabinoids and their metabolites in urine samples of consumers. Conclusions: The screening method applied JWH-122, JWH-210, UR-144 and their metabolites in urine of consumers can be applied to other compounds of the JWH family.