Analysis of new psychoactive substances in human urine by ultra-high performance supercritical fluid and liquid chromatography: Validation and comparison.

New psychoactive substances represent serious social and health problem as tens of new compounds are detected in Europe annually. They often show structural proximity or even isomerism, which complicates their analysis. Two methods based on ultra high performance supercritical fluid chromatography and ultra high performance liquid chromatography with mass spectrometric detection were validated and compared. A simple dilute-filter-and-shoot protocol utilizing propan-2-ol or methanol for supercritical fluid or liquid chromatography, respectively, was proposed to detect and quantify 15 cathinones and phenethylamines in human urine. Both methods offered fast separation (<3 min) and short total analysis time. Precision was well <15% with a few exceptions in liquid chromatography. Limits of detection in urine ranged from 0.01 to 2.3 ng/mL, except for cathinone (5 ng/mL) in supercritical fluid chromatography. Nevertheless, this technique distinguished all analytes including four pairs of isomers, while liquid chromatography was unable to resolve fluoromethcathinone regioisomers. Concerning matrix effects and recoveries, supercritical fluid chromatography produced more uniform results for different compounds and at different concentration levels. This work demonstrates the performance and reliability of supercritical fluid chromatography and corroborates its applicability as an alternative tool for analysis of new psychoactive substances in biological matrixes.

Detection of Volatile Organic Compounds in a Drop of Urine by Ultrasonic Nebulization Extraction Proton Transfer Reaction Mass Spectrometry.

Detection of volatile organic compounds (VOCs) in human urine has potential application value in screening for disease and toxin exposure. However, the current technologies are too slow to detect the concentration of VOCs in fresh urine. In this study, we developed a novel ultrasonic nebulization extraction proton transfer reaction mass spectrometry (UNE-PTR-MS) technology. The urinary VOCs can be rapidly extracted to gaseous VOCs using the UNE system and then delivered using a carrier gas to the PTR-MS instrument for rapid detection. The carrier gas flow and sample size were optimized to 100 mL/min and 100 µL, respectively. The limits of detection (LODs) and response time of the UNE-PTR-MS were evaluated by detecting three VOCs that are common in human urine: methanol, acetaldehyde, and acetone. The LODs determined for methanol (4.47 µg/L), acetaldehyde (1.98 µg/L), and acetone (3.47 µg/L) are 2-3 orders of magnitude lower than the mean concentrations of that in healthy human urine. The response time of the UNE-PTR-MS is 34 s and only 0.66 mL of urine is required for a full scan. The repeatability of this UNE-PTR-MS was evaluated, and the relative standard deviations of 5 independent determinations were between 4.62% and 5.21%. Lastly, the UNE-PTR-MS was applied for detection of methanol, acetaldehyde, and acetone in real human urine to test matrix effects, yielding relative recoveries of between 88.39% and 94.54%. These results indicate the UNE-PTR-MS can be used for the rapid detection of VOCs in a drop of urine and has practical potential for diagnosing disease or toxin exposure.

Improved detection of alcohol consumption using the novel marker phosphatidylethanol in the transplant setting: results of a prospective study.

Phosphatidylethanol (PEth) is a new, highly specific alcohol marker. The aim of this study was to assess its diagnostic value in the liver transplant setting. In 51 pre- and 61 post-transplant patients with underlying alcoholic liver disease PEth, ethanol, methanol, carbohydrate-deficient transferrin (CDT), and ethyl glucuronide in urine (uEtG) and hair (hEtG) were tested and compared with patients' questionnaire reports. Twenty-eight (25%) patients tested positive for at least one alcohol marker. PEth alone revealed alcohol consumption in 18% of patients. With respect to detection of alcohol intake in the preceding week, PEth showed a 100% sensitivity. PEth testing was more sensitive than the determination of ethanol, methanol, CDT or uEtG alone [sensitivity 25% (confidence interval (CI) 95%, 7-52%), 25% (7-52%), 21% (6-45%) and 71% (41-91%), respectively], or ethanol, methanol and uEtG taken in combination with 73% (45-92%). Specificity of all markers was 92% or higher. Additional testing of hEtG revealed alcohol consumption in seven patients, not being positive for any other marker. Phosphatidylethanol was a highly specific and sensitive marker for detection of recent alcohol consumption in pre- and post-transplant patients. The additional determination of hEtG was useful in disclosing alcohol consumption 3-6 months retrospectively.

Urine methanol concentration and alcohol hangover severity.

BACKGROUND: Congeners are substances, other than ethanol, that are produced during fermentation. Previous research found that the consumption of congener-rich drinks contributes to the severity of alcohol hangover. Methanol is such a congener that has been related to alcohol hangover. Therefore, the aim of this study was to examine the relationship between urine methanol concentration and alcohol hangover severity. METHODS: N = 36 healthy social drinkers (22 females, 14 males), aged 18-30 years old, participated in a naturalistic study, comprising a hangover day and a control day (no alcohol consumed the previous day). N = 18 of them had regular hangovers (the hangover group), while the other N = 18 claimed to be hangover-immune (hangover-immune group). Overall hangover severity was assessed, and that of 23 individual hangover symptoms. Urine methanol concentrations on the hangover and control days were compared, and correlated to hangover (symptom) severity. RESULTS: Urine methanol concentration was significantly higher on hangover days compared to control days (p = 0.0001). No significant differences in urine methanol concentration were found between the hangover group and hangover-immune group. However, urine methanol concentration did not significantly correlate with overall hangover severity (r = -0.011, p = 0.948), nor with any of the individual hangover symptoms. These findings were observed also when analyzing the data separately for the hangover-immune group. In the hangover group, a significant correlation with urine methanol concentration was found only with vomiting (r = 0.489, p = 0.037). CONCLUSION: No significant correlation was observed between urine methanol concentration and hangover severity, nor with individual core hangover symptoms.

Simultaneous Determination of Methanol, Ethanol and Formic Acid in Serum and Urine by Headspace GC-FID.

A simple, cost-effective headspace gas chromatography (GC) method coupled with GC with flame ionization detection for simultaneous determination of methanol, ethanol and formic acid was developed and validated for clinical and toxicological purposes. Formic acid was derivatized with an excess of isopropanol under acidic conditions to its volatile isopropyl ester while methanol and ethanol remained unchanged. The entire sample preparation procedure is complete within 6 min. The design of the experiment (the face-centered central composite design) was used for finding the optimal conditions for derivatization, headspace sampling and chromatographic separation. The calibration dependences of the method were quadratic in the range from 50 to 5,000 mg/L, with adequate accuracy (89.0-114.4%) and precision (<12%) in the serum. The new method was successfully used for determination of selected analytes in serum samples of intoxicated patients from among those affected by massive methanol poisonings in the Czech Republic in 2012.

Human metabolism of Δ3-carene and renal elimination of Δ3-caren-10-carboxylic acid (chaminic acid) after oral administration.

We studied the human in vivo metabolism of Δ(3)-carene (CRN), a natural monoterpene which commonly occurs in the human environment. Four healthy human volunteers were orally exposed to a single dose of 10 mg CRN. Each volunteer gave one urine sample before administration and subsequently collected each urine sample within 24 h after administration. The concentration of the proposed CRN metabolites Δ(3)-caren-10-ol (CRN-10-OH), Δ(3)-caren-10-carboxylic acid (chaminic acid, CRN-10-COOH), and Δ(3)-caren-3,4-diol (CRN-3,4-OH) were determined using a very specific and sensitive GC-MS/MS procedure. Other CRN metabolites were investigated using GC-PCI-MS Q1 scan analyses. CRN-10-COOH was detected in each urine sample with maximum concentration (113.0-1,172.9 µg L(-1)) 2-3 h after administration, whereas CRN-10-OH and CRN-3,4-OH were not detected in any of the samples. The renal excretion kinetics of CRN-10-COOH showed an elimination half-life of about 3 h. The cumulative excretion of CRN-10-COOH within 24 h after exposure correlated with about 2 % of the applied dose. The GC-PCI-MS Q1 scan analysis indicated several additional human CRN metabolites; thereof, six spectra enabled the prediction of the corresponding chemical structure. The results of the study indicate that CRN-10-COOH is a relevant product of the human in vivo metabolism of CRN. The oxidation of its allylic methyl group proceeds until the acidic structure without interruption. Thus, the generation of the alcoholic intermediate appeared to be the rate-determining step of this metabolic route. Nevertheless, the proportion of CRN-10-COOH in the CRN metabolism is low, and other oxidative metabolites are likely. This hypothesis was confirmed by the discovery of additional human CRN metabolites, whose predicted chemical structures fit in with further oxidative products of CRN metabolism.

A singular case of survival after acute methanol poisoning: toxicological and neuroimaging findings.

Acute methanol poisoning is a relatively uncommon and dangerous form of intoxication. It generally occurs after suicidal or accidental events and can be potentially fatal if not diagnosed and treated promptly. Here reported is the case of a 52-year-old Romanian man who survived acute methanol intoxication. Therefore, it was possible to monitor the clinical evolution, the arterial blood gas assay and toxicological research of methanol in blood and urine, as well as the brain damage by computed tomography and magnetic resonance imaging during a period of 20 days after the intake.

Comparison of direct and indirect alcohol markers with PEth in blood and urine in alcohol dependent inpatients during detoxication.

The importance of direct and indirect alcohol markers to evaluate alcohol consumption in clinical and forensic settings is increasingly recognized. While some markers are used to prove abstinence from ethanol, other markers are suitable for detection of alcohol misuse. Phosphatidyl ethanol (PEth) is ranked among the latter. There is only little information about the correlation between PEth and other currently used markers (ethyl glucuronide, ethyl sulfate, carbohydrate deficient transferrin, gamma-glutamyl transpeptidase, and methanol) and about their decline during detoxification. To get more information, 18 alcohol-dependent patients in withdrawal therapy were monitored for these parameters in blood and urine for up to 19 days. There was no correlation between the different markers. PEth showed a rapid decrease at the beginning of the intervention, a slow decline after the first few days, and could still be detected after 19 days of abstinence from ethanol.

[Confirmed poisonings with ethylene glycol and methanol in south Poland in the years 2010-2012 based on results from toxicological laboratories in Kraków and Sosnowiec]. / Potwierdzone zatrucia glikolem etylenowym i alkoholem metylowym w Polsce poludniowej w latach 2010-2012 na podstawie wyników oznaczen laboratoriów toksykologicznych w Krakowie i Sosnowcu.

The purpose of the research was to present the number of ethylene glycol and methanol poisonings in south Poland in the years 2010-2012, based on data from toxicological laboratories in Kraków and Sosnowiec. Total numbers of positive determinations of the toxic alcohols were 380-ethylene glycol and 152-methanol. Most of the patients poisoned with the toxic alcohols were men (87.4%), the mean age of the patients was 48.1 years. Mean ethylene glycol concentration in samples from poisoned patients was 57.5 mg/dl in serum and 286.2 mg/dl in urine; mean blood methanol concentration was 1.4 g/l. Samples collected from poisoned patients treated on the area of whole voivodeship were determined in toxicology laboratories. According to information about orderers of ethylene glycol and methanol tests, positive results of the toxic alcohols were the most often in big cities and in cities, where department of toxicology were located (Kraków and Sosnowiec). In many cases patients were treated in hospitals in small cities, and samples collected from patients were transported to perform toxicological determination. The study shows, that intoxications with ethylene glycol and methanol are a big problem in Poland and the number of methanol poisonings markedly increased in the years 2010-2012.