URINARY ETHYL GLUCURONIDE AND 5-HYDROXYTRYPTOPHOL LEVELS DURING REPEATED ETHANOL INGESTION IN HEALTHY HUMAN SUBJECTS

Taisto Sarkola, Helen Dahl1, C. J. Peter Eriksson and Anders Helander1,*

Department of Mental Health and Alcohol Research, National Public Health Institute, POB 33, FIN-00251 Helsinki, Finland and
1 Department of Clinical Neuroscience, Karolinska Institutet, SE-171 76 Stockholm, Sweden

Received 21 October 2002; in revised form 3 February 2003; in revised form 12 February 2003; accepted 12 March 2003


    ABSTRACT
 TOP
 FOOTNOTES
 ABSTRACT
 INTRODUCTION
 SUBJECTS AND METHODS
 RESULTS
 DISCUSSION
 ACKNOWLEDGEMENTS
 REFERENCES
 
Aims: This study investigated the stability and reproducibility of urinary ethyl glucuronide (EtG) and the 5-hydroxytryptophol (5-HTOL) to 5-hydroxyindole-3-acetic acid (5-HIAA) ratio, both of which are used as biochemical markers of recent alcohol consumption, after single and multiple oral doses of ethanol in healthy human subjects. Methods: Nine females aged 19–27 years drank ethanol (8%, w/v, in juice) or placebo (juice) in random order. The intervention consisted of 0.4 g/kg (22–28 g) of ethanol or placebo twice daily (in the morning and evening) during 8 consecutive days, starting in the evening on day 1. Spot urine samples of the first morning void were collected during the 8-day drinking period and for another 3 days (days 9–11) with no intake of ethanol or placebo. Ethanol, EtG, 5-HTOL and 5-HIAA were determined in the urine samples by headspace GC, LC–MS, GC–MS and HPLC, respectively. Results: The individual results during the drinking period were highly variable, both within and between subjects, ranging from 0–7.3 mmol/l for ethanol, 1.4–71.0 mg/l for EtG, 0.1–4.5 mg/mmol for the EtG/creatinine ratio, and 2–109 nmol/µmol for 5-HTOL/5-HIAA. The placebo group consistently showed negative values for ethanol (< 0.1 mmol/l) and 5-HTOL/5-HIAA (< 15 nmol/µmol), but two samples were positive for EtG (> 0.1 mg/l). In the morning of day 9 (i.e. ~14–15 h after the last dose), ethanol was no longer measurable in urine and the 5-HTOL/5-HIAA ratio had returned to below the reference value, but detectable levels of EtG (11.3 ± 6.0 mg/l, mean ± SD) and the EtG/creatinine ratio (1.0 ± 0.3 mg/mmol) were found in all samples. Conclusions: The results confirm the increase in urinary EtG and 5-HTOL levels during acute ethanol intake, although the individual values were highly variable both within and between subjects. No significant accumulation of either compound occurred upon multiple-dose administration of 0.8 g/kg (44–57 g) ethanol per day for ~1 week.


    INTRODUCTION
 TOP
 FOOTNOTES
 ABSTRACT
 INTRODUCTION
 SUBJECTS AND METHODS
 RESULTS
 DISCUSSION
 ACKNOWLEDGEMENTS
 REFERENCES
 
The traditional and most objective way to prove recent intake of alcohol is to demonstrate the presence of ethanol in body fluids or breath. Determination of ethanol in blood or urine is routinely performed in the laboratory with the use of gas chromatographic or enzymatic methods, whereas analysing expired air with hand-held breathalysers or saliva with dip-sticks are useful methods for field applications (Jones, 1990Go). A drawback is that the ingested ethanol is cleared fairly rapidly from the body at a rate of ~0.1 g/kg per hour, primarily due to metabolism in the liver, with even more rapid elimination noted in heavy drinkers. A person may thus have consumed substantial amounts of alcohol (at least 1 bottle of wine, or ~4–5 cans of beer, or ~5–6 drinks; corresponding to 60–80 g of ethanol) in the evening and still present a negative breath or blood ethanol value the next morning (Bendtsen et al., 1998Go; Helander et al., 1999Go). Compared with blood and breath, ethanol is usually detectable for slightly longer periods in the urine (Helander et al., 1996Go), owing to retention of urine in the bladder.

To identify persons who have been drinking excessively for longer periods, biochemical alcohol markers such as carbohydrate-deficient transferrin (CDT) and {gamma}-glutamyltransferase (GGT) in serum are often applied (Conigrave et al., 2002Go). However, CDT and GGT respond only to repeated heavy alcohol consumption over several weeks or months. Filling the gap between ethanol measurement on the one hand and markers for excessive long-term drinking on the other therefore stands as an important goal in alcohol marker research. In recent years, a number of laboratory methods for acute alcohol intake that show a prolonged detection window compared with ethanol have been introduced. Testing urine for a raised concentration of the serotonin metabolite 5-hydroxytryptophol (5-HTOL) provides a method to reveal alcohol consumption within the preceding ~24 h, even for several hours after the ethanol is no longer measurable in body fluids or breath (Helander et al., 1993Go, 1994Go). To improve the accuracy of this test in routine clinical use, 5-HTOL is expressed as a ratio to the major serotonin metabolite 5-hydroxyindole-3-acetic acid (5-HIAA), because this compensates for variations caused by urine dilution and serotonin turnover (e.g. after dietary intake of serotonin) (Helander et al., 1992Go).

Ethyl glucuronide (EtG) is a non-oxidative direct metabolite of ethanol with a longer window of detection than the parent compound (Kamil et al., 1952Go; Jaakonmaki et al., 1967Go; Schmitt et al., 1995Go). Besides the two-stage oxidation process via alcohol and aldehyde dehydrogenase that accounts for 95–98% of total ethanol elimination, a very small fraction (< 0.1%) of the ingested dose undergoes conjugation with UDP-glucuronic acid to produce EtG, which is eventually excreted in the urine (Dahl et al., 2002Go; Goll et al., 2002Go). As for the urinary 5-HTOL/5-HIAA ratio, a positive finding of EtG, preferably expressed as the EtG/creatinine ratio to compensate for urine dilution (Dahl et al., 2002Go), provides a strong indication that the person was recently drinking alcohol, even when ethanol itself is no longer distinguishable from endogenous levels. While the baseline 5-HTOL/5-HIAA ratio is seemingly not influenced by repeated alcohol consumption (Helander et al., 1996Go), EtG has been reported to persist in the urine for up to ~75–85 h after last intake (Seidl et al., 2001Go). This observation, together with reports of consistently elevated levels among alcohol misusers (Schmitt et al., 1997Go; Seidl et al., 2001Go), suggest that EtG may accumulate upon prolonged drinking.

In contrast to the markers of long-term heavy alcohol intake, an acute alcohol marker should not accumulate on repeated ethanol exposure, as this would complicate the interpretation of single test results. The present study was therefore undertaken to examine the stability and reproducibility of EtG and 5-HTOL levels in urine after single and multiple oral doses of ethanol in healthy human subjects.


    SUBJECTS AND METHODS
 TOP
 FOOTNOTES
 ABSTRACT
 INTRODUCTION
 SUBJECTS AND METHODS
 RESULTS
 DISCUSSION
 ACKNOWLEDGEMENTS
 REFERENCES
 
Study subjects
Nine healthy non-pregnant Caucasian female students (mean age ± SD: 23 ± 2 years, range 19–27; body weight 61 ± 6 kg, range 55–71), with no current use of medication except that all were taking oral contraceptives (35 µg ethinyl oestradiol plus 75 µg gestodene), were recruited for the study by personal contact among acquaintances. All subjects showed normal plasma GGT levels before entering the study (18 ± 7 U/l, range 9–38) and none reported prior regular alcohol consumption exceeding 12 standard drinks (one drink = 12 g ethanol) per week. Accordingly, they were classified as light drinkers. No intake of alcoholic beverages was allowed for the 1 week preceding the experimental sessions and only the alcohol provided by the staff was allowed during the study period. The participants were encouraged not to make any changes in their usual diets or habits during the study.

Study design
The study was a controlled interventional study with a cross-over design. All experiments were started at day 14 of the menstrual cycle (i.e. the seventh day of taking the pill) to compensate for any potential interference by the phase of the menstrual cycle. The menstrual cycle phases and use of oral contraceptives do not influence ethanol metabolism (Mumenthaler et al., 1999Go), but any likely effects on 5-HTOL and EtG have not been studied. The women were randomly assigned to alcohol or placebo with 4 and 5 subjects in each group and the alcohol (8% ethanol, w/v, in juice) or placebo (an equal volume of juice) was ingested during 8 consecutive days. Fresh ethanol and placebo drinks were provided in sealed containers upon daily visits to the laboratory at 16:00 h for blood ethanol testing. Blood ethanol testing was carried out in order to detect any intake of alcohol besides the prescribed doses; the 0.4 g/kg ethanol dose was metabolized within about 6 h (Sarkola et al., 2001Go).

On the first day of the study (day 1), ethanol (0.4 g/kg, corresponding to 22.0–28.4 g) or placebo was ingested within 15 min at 16:00 h. Spot urine samples (40 ml in vials containing 1.0 g/l sodium azide) were collected at 0 (immediately before intake), 4 and 15 h, and venous blood samples were drawn at 0, 2, 3, 4, 5 and 6 h from intake. During the following 6 days (days 2–7), the ethanol (0.4 g/kg) or placebo was ingested in the morning (at 06:00–07:30 h) and in the evening before going to bed (at 21:00–00:00 h; total ethanol dose 0.8 g/kg per day). Urine samples were collected daily in the morning (first void and before ethanol or placebo intake) and blood samples in the afternoon at 16:00 h. On day 8, the ethanol or placebo was ingested in the morning and at 16:00 h. Urine samples were collected in the morning before intake, and urine and blood samples were taken from 16:00 h onwards as detailed above for day 1. Morning urine and afternoon blood sampling was then continued for another 3 days (day 9–11) with no intake of alcohol or placebo. During the next menstrual cycle, the same procedures were carried out with the ethanol and placebo groups reversed.

The blood samples (10 ml) were collected into Vacutainer tubes containing 22.5 mg of sodium fluoride and 22.5 mg of potassium oxalate as anticoagulants. The blood and urine samples were stored at –70°C until analysed.

The study was conducted in accordance with the guidelines proposed in The Declaration of Helsinki and approved by the Hospital District of Helsinki and Vusimaa, Ethical Committee for Research in Epidemiology and Public Health. Written informed consent was obtained from the participants before their inclusion in the study.

Measurement of ethanol and creatinine
The concentration of ethanol in blood and urine was determined by headspace gas chromatography (Sarkola and Eriksson, 2001Go). The intra- and inter-assay coefficients of variation (CV) were less than 5%, and the limit of quantification (LOQ) was 0.005 mmol/l. A cut-off of 0.1 mmol/l was chosen to indicate recent alcohol consumption. Urinary creatinine was determined using a VITROS 250 Chemistry System (Ortho-Clinical Diagnostics, Rochester, NY, USA). The intra- and inter-assay CV were less than 5% at a creatinine level of 0.44 mmol/l (n = 7), and the LOQ was 0.08 mmol/l.

Measurement of EtG
The concentration of EtG in urine was determined by a negative ion electrospray liquid chromatographic–mass spectrometric (LC–MS) method (Stephanson et al., 2002Go). The ions monitored were m/z 221 for EtG and m/z 226 for EtG–d5 (internal standard). The intra- and inter-assay CV of the method were less than 12%, and the LOQ was 0.1 mg/l (Stephanson et al., 2002Go). The EtG concentrations of unknown samples were determined from the peak area ratio between EtG and EtG–d5 by reference to the calibration curve. The EtG and EtG–d5 were purchased from Medichem Diagnostica (Steinenbronn, Germany).

Measurement of 5-HTOL and 5-HIAA
Urinary 5-HIAA was determined by high-performance liquid chromatography (HPLC) and 5-HTOL by gas chromatography– mass spectrometry (GC–MS) (Helander et al., 1996Go). For 5-HTOL, which is excreted almost entirely in conjugated form with glucuronic acid (Helander et al., 1995Go), enzymatic hydrolysis was made prior to analysis. The intra- and inter-assay CV of the assays were less than 7%, and the LOQ were 1 µmol/l for 5-HIAA and 50 nmol/l for 5-HTOL. To compensate for variations in 5-HIAA and 5-HTOL concentrations caused by urine dilution, the 5-HTOL/5-HIAA ratio was calculated. The reference limit used in clinical practice to discriminate between a normal and an elevated 5-HTOL/ 5-HIAA ratio (i.e. indicative of any recent drinking) has been set at < 15 (nmol/µmol) (Helander et al., 1994Go).

Statistics
Results are expressed as mean ± standard deviation (SD). The Wilcoxon test for paired samples was used for statistical evaluation of the data. A two-tailed P value of less than 0.05 was considered statistically significant.


    RESULTS
 TOP
 FOOTNOTES
 ABSTRACT
 INTRODUCTION
 SUBJECTS AND METHODS
 RESULTS
 DISCUSSION
 ACKNOWLEDGEMENTS
 REFERENCES
 
The blood samples collected at 16:00 h on days 1–11, and the urine samples collected in the morning on days 9–11, were all found to be negative for ethanol (< 0.1 mmol/l), thereby excluding any major intake of alcohol besides the prescribed doses during the study period. Furthermore, no significant changes in plasma GGT levels were observed after the alcohol drinking period (before: 18 ± 7 U/l, range 9–38; after: 19 ± 7 U/l, range 11–36; F = 2.0, P = 0.2).

During the ethanol drinking period, the individual 5-HTOL/ 5-HIAA results for the urine samples collected in the morning on days 3–8, when the 0.4 g/kg ethanol dose had been ingested on the previous evening, were elevated in 6, 8, 7, 7, 7 and 7, respectively, out of the total of 9 subjects (i.e. ~78% of the samples were positive for 5-HTOL/5-HIAA on average). This compares with positive ethanol values in 5, 4, 7, 5, 4 and 5 subjects (~56%). In contrast, measurable EtG levels were observed in all 9 urine samples of the 9 subjects (100%). The placebo group consistently showed negative urinary ethanol values and the 5-HTOL/5-HIAA ratios were below the reference value of 15 (nmol/µmol). However, two subjects showed one positive EtG value each (0.60 and 0.12 mg/l, respectively) during the placebo period.

The individual morning urine results were highly variable between subjects during the ethanol drinking period (Fig. 1Go). Accordingly, the ethanol values ranged from 0 (i.e. below the LOQ of 0.005 mmol/l) to 7.3 mmol/l, 1.4–71.0 mg/l for EtG, 0.1–4.5 mg/mmol for the EtG/creatinine ratio, and 2–109 nmol/ µmol for the 5-HTOL/5-HIAA ratio. There was also a considerable variation in the results between different days for some individuals (data not shown), which was most likely explained by occasional voiding during night-time (although this was not recorded). The individual results for the six urine samples collected on days 3–8 yielded CV values of 21–137% (mean 69%) for EtG, 24–118% (mean 53%) for EtG/ creatinine, and 21–126% (mean 65%) for 5-HTOL/5-HIAA. For comparison, the corresponding CV values for 5-HTOL/ 5-HIAA during the placebo period were considerably lower at 12–43% (mean 22%).



View larger version (19K):
[in this window]
[in a new window]
 
Fig 1. Concentrations of ethanol and ethyl glucuronide (EtG), and the EtG to creatinine (EtG/Crea) and 5-hydroxytryptophol to 5-hydroxyindole-3-acetic acid (5-HTOL/5-HIAA) ratios in morning urine samples collected during ethanol and placebo intake. The first morning urine void was collected at 06:30–07:30 h during ethanol (0.4 g/kg twice daily, once in the morning and once in the evening) and placebo drinking periods (shaded area). See Methods for full details on the study design. Values are mean ± SD (n = 9).

 
In the urine samples collected in the morning on day 9 (i.e. ~14–15 h after the last intake of 0.4 g/kg ethanol) the ethanol values were below the cut-off limit (< 0.1 mmol/l) and the 5-HTOL/5-HIAA ratio had returned to within the reference interval (< 15 nmol/µmol). However, the mean value for 5-HTOL/5-HIAA (7.3 ± 1.1 nmol/µmol) was significantly higher than at the beginning of the study period (first urine sample of day 1: 4.9 ± 1.4, P < 0.01) and the second post-drinking day (day 10: 5.6 ± 1.9, P < 0.05). In contrast with the above data, detectable levels of EtG (11.3 ± 6.0 mg/l) and, accordingly, the EtG/creatinine ratio (1.0 ± 0.3 mg/mmol) were present in all urine samples of day 9 (Fig. 1Go). One subject also had a detectable EtG concentration (0.26 mg/l) in the morning sample collected on day 10 of the study (i.e. ~38 h after the last dose) and this individual showed the highest urinary EtG concentration (80.5 mg/l) at 4 h after the last drink (day 8). This subject also presented one of the positive EtG results (0.60 mg/l) during the placebo period, the origin of which is unknown.

The elimination rate of ethanol was significantly increased by 24% on average at the end of the drinking period (day 8: 0.112 ± 0.013 g/kg per hour) compared with the initial experiment (day 1: 0.090 ± 0.013 g/kg per hour; P = 0.006) (Sarkola et al., 2001Go). The EtG/creatinine and 5-HTOL/5-HIAA ratios obtained during the first and second acute drinking experiments are given in Fig. 2Go. At 16:00 h on day 8, the EtG/creatinine and 5-HTOL/5-HIAA values were both elevated, but this resulted from the intake of ethanol on the same morning. However, the urine samples collected at 4 h after intake were not significantly different between the days, whereas at 15 h the EtG/creatinine ratio was significantly (P < 0.05) lower on day 8 (Fig. 2Go).



View larger version (19K):
[in this window]
[in a new window]
 
Fig 2. Ratios of ethyl glucuronide to creatinine (EtG/Crea) and 5-hydroxytryptophol to 5-hydroxyindole-3-acetic acid (5-HTOL/5-HIAA) in urine samples collected in an acute drinking experiment, before and after a period of controlled drinking. An acute drinking experiment (0.4 g/kg at 16:00 h) was performed before (white bars) and after (black bars) a 1-week period of controlled ethanol intake at a total of 0.8 g/kg per day (0.4 g/kg twice daily; once in the morning and once in the evening). The EtG/Crea and 5-HTOL/ 5-HIAA values at zero time at the end of the drinking period (t = 0, black bars) were elevated due to the intake of 0.4 g/kg ethanol about 9 h earlier in the morning. Values are mean ± SD (n = 9). *P < 0.05.

 

    DISCUSSION
 TOP
 FOOTNOTES
 ABSTRACT
 INTRODUCTION
 SUBJECTS AND METHODS
 RESULTS
 DISCUSSION
 ACKNOWLEDGEMENTS
 REFERENCES
 
Testing individuals for an excessive and potentially harmful alcohol consumption level with the use of laboratory parameters has mainly employed general indicators of body and organ effects included in ordinary blood-chemistry and haematological profiles, such as the liver function test GGT and the mean corpuscular volume of erythrocytes (MCV) (Helander, 2001Go). It was not until the early 1990s that CDT was introduced as an alcohol-specific test (Stibler, 1991Go). Although these alcohol markers have been found useful as objective clinical tools to monitor compliance and relapse drinking during out-patient treatment of alcohol-dependent subjects, a common limitation is that they do not respond until after several weeks or months of prolonged heavy alcohol consumption.

In some situations, laboratory tests to indicate any recent consumption of alcohol may be more useful. The introduction of sensitive and specific alcohol markers with a prolonged detection window compared with ethanol, such as the 5-HTOL/ 5-HIAA ratio (Helander et al., 1996Go) and EtG (Seidl et al., 2001Go) in urine, has allowed for new and improved diagnostic and treatment strategies (Helander, 1998Go; Spies et al., 1999Go). During out-patient treatment, for example, the 5-HTOL/5-HIAA ratio provided a much more sensitive method compared with utilizing breath or blood analysis to detect consumption of even moderate amounts of alcohol within the past ~24 h (Helander et al., 1999Go). In certain workplaces, tests of acute alcohol consumption may be used upon return to safety-sensitive duties (Hagan and Helander, 1997Go), because it is well-known that the after-effects of drinking (i.e. hangover symptoms) can impair behaviour and thereby increase the risk of becoming involved in accidents (Wiese et al., 2000Go).

The present study confirmed previous observations that urinary 5-HTOL/5-HIAA and EtG values are increased during acute ethanol intake. The levels for both markers were within the ranges typically observed in urine samples collected during routine screening for recent alcohol consumption (Helander et al., 1999Go; Stephanson et al., 2002Go). The detection time for EtG was found to be somewhat longer than for 5-HTOL/ 5-HIAA. A previous study demonstrated that the detection window for recent drinking by an increased urinary level of 5-HTOL, which is excreted mainly as the glucuronic acid conjugate (Helander et al., 1995Go), becomes prolonged at higher turnover of 5-HT (i.e. at higher concentrations of 5-HTOL) (Helander and Some, 2000Go). Accordingly, because EtG levels are more than 100-fold higher than 5-HTOL glucuronide levels after an acute ethanol dose (Helander et al., 1993Go; Schmitt et al., 1997Go), it is possible that the longer detection time observed for EtG compared with 5-HTOL/5-HIAA simply results from the much higher concentrations of EtG.

Given the high sensitivity for EtG in detecting recent intake of very small amounts of ethanol (Stephanson et al., 2002Go), it cannot be excluded that the two positive EtG results observed during the placebo period resulted from the intake of low-alcohol, or ‘alcohol-free’ (< 0.5% ethanol), beverages. Endogenous concentrations of ethanol, on the other hand, are not sufficient to produce a detectable EtG (Janda and Alt, 2001Go; Stephanson et al., 2002Go). However, it should always be considered that self-reports of alcohol consumption may have low accuracy (Helander and Eriksson, 2002Go).

In contrast to laboratory tests used to indicate long-term heavy alcohol intake, a marker of acute drinking should preferably cover a well-defined time-window and not accumulate on repeated ethanol exposure, as this would complicate the interpretation of single test results. The present study found no indication of accumulation of either 5-HTOL or EtG in the body upon repeated ethanol exposure at a level of 0.8 g/kg (44–57 g) per day for a period of ~1 week. For EtG, this is in line with theoretical results from a computer simulation (Droenner et al., 2002Go). On the contrary, when the acute ethanol challenge was repeated after the 1-week drinking period, a significantly lower EtG/creatinine ratio was observed at 15 h after intake, suggesting a reduced biological half-life for urinary EtG on repeated ethanol dosage. However, because the ethanol elimination rate was also found to be faster on the second challenge (Sarkola et al., 2001Go), the lower EtG/ creatinine ratios were, most likely, related to the lower concentration of the parent compound ethanol.

There were considerable variations in the urinary ethanol, EtG and 5-HTOL/5-HIAA values during the drinking period, both between and within subjects. This was probably due to a combination of biological variation and occasional voiding during night-time. The variable ethanol, 5-HTOL/5-HIAA and EtG results observed in previous studies on mixed populations (Jones and Helander, 1999Go; Dahl et al., 2002Go) were confirmed in the present study, which involved women only. The gender effect for EtG has not yet been evaluated in detail, but no sex difference was apparent in one study (Dahl et al., 2002Go). Gender is known not to influence the urinary 5-HTOL/5-HIAA ratio (Helander et al., 1996Go). Furthermore, the variability for EtG could not be explained by differences in urine dilution, as it remained high when EtG was expressed as a ratio to creatinine. It should be noted that the study protocol allowed for some hours difference in the time elapsing between drinking the ethanol and collecting the urine sample, which could also have influenced the variability of test values.

In conclusion, the present results confirmed that the urinary excretion of EtG and 5-HTOL become increased following acute ethanol intake, and that levels remain elevated for several hours after the ethanol is no longer measurable in body fluids or breath. Most importantly, no significant accumulation of either compound was demonstrated upon multiple-dose administration of ethanol corresponding to 4–5 standard drinks per day for ~1 week. Accordingly, these results indicate that 5-HTOL/5-HIAA and EtG can be used as sensitive and specific tests to assess recent drinking in light-to-moderate as well as chronic heavy consumers, with a slightly longer detection time for EtG.


    ACKNOWLEDGEMENTS
 TOP
 FOOTNOTES
 ABSTRACT
 INTRODUCTION
 SUBJECTS AND METHODS
 RESULTS
 DISCUSSION
 ACKNOWLEDGEMENTS
 REFERENCES
 
The authors wish to thank Mrs Hilkka Salohalla and Mrs Tuula Mäkelä for skilful technical assistance. This work was supported in part by grants from Societatis Medicorum Fennicae, Magnus Ehrnrooths Foundation, Oskar Öflund Foundation, Stockmann Foundation, Perklén Foundation and the Karolinska Institutet.


    FOOTNOTES
 TOP
 FOOTNOTES
 ABSTRACT
 INTRODUCTION
 SUBJECTS AND METHODS
 RESULTS
 DISCUSSION
 ACKNOWLEDGEMENTS
 REFERENCES
 
* Author to whom correspondence should be addressed at: Alcohol Laboratory, L7:03, Karolinska Hospital, SE-171 76 Stockholm, Sweden. Back


    REFERENCES
 TOP
 FOOTNOTES
 ABSTRACT
 INTRODUCTION
 SUBJECTS AND METHODS
 RESULTS
 DISCUSSION
 ACKNOWLEDGEMENTS
 REFERENCES
 
Bendtsen, P., Jones, A. W. and Helander, A. (1998) Urinary excretion of methanol and 5-hydroxytryptophol as biochemical markers of recent drinking in the hangover state. Alcohol and Alcoholism 33, 431–438.[Abstract]

Conigrave, K. M., Degenhardt, L. J., Whitfield, J. B., Saunders, J. B., Helander, A. and Tabakoff, B. (2002) CDT, GGT, and AST as markers of alcohol use: the WHO/ISBRA collaborative project. Alcoholism: Clinical and Experimental Research 26, 332–339.[ISI][Medline]

Dahl, H., Stephanson, N., Beck, O. and Helander, A. (2002) Comparison of urinary excretion characteristics of ethanol and ethyl glucuronide. Journal of Analytical Toxicology 26, 201–204.[ISI][Medline]

Droenner, P., Schmitt, G., Aderjan, R. and Zimmer, H. (2002) A kinetic model describing the pharmacokinetics of ethyl glucuronide in humans. Forensic Science International 126, 24–29.[CrossRef][ISI][Medline]

Goll, M., Schmitt, G., Ganssmann, B. and Aderjan, R. E. (2002) Excretion profiles of ethyl glucuronide in human urine after internal dilution. Journal of Analytical Toxicology 26, 262–266.[ISI][Medline]

Hagan, R. L. and Helander, A. (1997) Urinary 5-hydroxytryptophol following acute ethanol consumption: clinical evaluation and potential aviation applications. Aviation, Space and Environmental Medicine 68, 30–34.[ISI][Medline]

Helander, A. (1998) Monitoring relapse drinking during disulfiram therapy by assay of urinary 5-hydroxytryptophol. Alcoholism: Clinical and Experimental Research 22, 111–114.[ISI][Medline]

Helander, A. (2001) Biological markers of alcohol use and abuse in theory and practice. In Alcohol in Health and Disease, Agarwal, D. P. and Seitz, H. K. eds, pp. 177–205. Marcel Dekker, Inc., New York.

Helander, A. and Eriksson, C. J. P. (2002) Laboratory tests for acute alcohol consumption: results of the WHO/ISBRA study on state and trait markers of alcohol use and dependence. Alcoholism: Clinical and Experimental Research 26, 1070–1077.[ISI][Medline]

Helander, A. and Some, M. (2000) Dietary serotonin and alcohol combined may provoke adverse physiological symptoms due to 5-hydroxytryptophol. Life Sciences 67, 799–806.[CrossRef][ISI][Medline]

Helander, A., Wikström, T., Löwenmo, C., Jacobsson, G. and Beck, O. (1992) Urinary excretion of 5-hydroxyindole-3-acetic acid and 5-hydroxytryptophol after oral loading with serotonin. Life Sciences 50, 1207–1213.[CrossRef][ISI][Medline]

Helander, A., Beck, O., Jacobsson, G., Löwenmo, C. and Wikström, T. (1993) Time course of ethanol-induced changes in serotonin metabolism. Life Sciences 53, 847–855.[CrossRef][ISI][Medline]

Helander, A., Beck, O. and Borg, S. (1994) The use of 5-hydroxytryptophol as an alcohol intake marker. Alcohol and Alcoholism Supplement 2, 497–502.

Helander, A., Beck, O. and Boysen, L. (1995) 5-Hydroxytryptophol conjugation in man: influence of alcohol consumption and altered serotonin turnover. Life Sciences 56, 1529–1534.[CrossRef][ISI][Medline]

Helander, A., Beck, O. and Jones, A. W. (1996) Laboratory testing for recent alcohol consumption: comparison of ethanol, methanol, and 5-hydroxytryptophol. Clinical Chemistry 42, 618–624.[Abstract/Free Full Text]

Helander, A., von Wachenfeldt, J., Hiltunen, A., Beck, O., Liljeberg, P. and Borg, S. (1999) Comparison of urinary 5-hydroxytryptophol, breath ethanol, and self-report for detection of recent alcohol use during outpatient treatment: a study on methadone patients. Drug and Alcohol Dependence 56, 33–38.[CrossRef][ISI][Medline]

Jaakonmaki, P. I., Knox, K. L., Horning, E. C. and Horning, M. G. (1967) The characterization by gas-liquid chromatography of ethyl ß-d-glucosiduronic acid as a metabolite of ethanol in rat and man. European Journal of Pharmacology 1, 63–70.[CrossRef][Medline]

Janda, I. and Alt, A. (2001) Improvement of ethyl glucuronide determination in human urine and serum samples by solid-phase extraction. Journal of Chromatography B 758, 229–234.[CrossRef][ISI]

Jones, A. W. (1990) Excretion of alcohol in urine and diuresis in healthy men in relation to their age, the dose administered and the time after drinking. Forensic Science International 45, 217–224.[ISI][Medline]

Jones, A. W. and Helander, A. (1999) Time course and reproducibility of urinary excretion profiles of ethanol, methanol, and the ratio of serotonin metabolites after intravenous infusion of ethanol. Alcoholism: Clinical and Experimental Research 23, 1921–1926.[ISI][Medline]

Kamil, I. A., Smith, J. N. and Williams, R. T. (1952) A new aspect of ethanol metabolism: isolation of ethyl glucuronide. Biochemical Journal 51, 32–33.

Mumenthaler, M. S., Taylor, J. L., O’Hara, R., Fisch, H. U. and Yesavage, J. A. (1999) Effects of menstrual cycle and female sex steroids on ethanol pharmacokinetics. Alcoholism: Clinical and Experimental Research 23, 250–255.[ISI][Medline]

Sarkola, T. and Eriksson, C. J. P. (2001) Effect of 4-methylpyrazole on endogenous plasma ethanol and methanol levels in humans. Alcoholism: Clinical and Experimental Research 25, 513–516.[ISI][Medline]

Sarkola, T., Ahola, L., von der Pahlen, B. and Eriksson, C. J. P. (2001) Lack of effect of alcohol on ethinylestradiol in premenopausal women. Contraception 63, 19–23.[CrossRef][ISI][Medline]

Schmitt, G., Aderjan, R., Keller, T. and Wu, M. (1995) Ethyl glucuronide: an unusual ethanol metabolite in humans. Synthesis, analytical data, and determination in serum and urine. Journal of Analytical Toxicology 19, 91–94.[ISI][Medline]

Schmitt, G., Droenner, P., Skopp, G. and Aderjan, R. (1997) Ethyl glucuronide concentration in serum of human volunteers, teetotalers, and suspected drinking drivers. Journal of Forensic Sciences 42, 1099–1102.[ISI][Medline]

Seidl, S., Wurst, F. M. and Alt, A. (2001) Ethyl glucuronide — a biological marker for recent alcohol consumption. Addiction Biology 6, 205–212.[CrossRef][ISI][Medline]

Spies, C. D., Herpell, J., Beck, O., Muller, C., Pragst, F., Borg, S. and Helander, A. (1999) The urinary ratio of 5-hydroxytryptophol to 5-hydroxyindole-3-acetic acid in surgical patients with chronic alcohol misuse. Alcohol 17, 19–27.[CrossRef][ISI][Medline]

Stephanson, N., Dahl, H., Helander, A. and Beck, O. (2002) Direct quantification of ethyl glucuronide in clinical urine samples by liquid chromatography–mass spectrometry. Therapeutic Drug Monitoring 24, 645–651.[CrossRef][ISI][Medline]

Stibler, H. (1991) Carbohydrate-deficient transferrin in serum: a new marker of potentially harmful alcohol consumption reviewed. Clinical Chemistry 37, 2029–2037.[Abstract/Free Full Text]

Wiese, J. G., Shlipak, M. G. and Browner, W. S. (2000) The alcohol hangover. Annals of Internal Medicine 132, 897–902.[Abstract/Free Full Text]





This Article
Abstract
FREE Full Text (PDF)
Alert me when this article is cited
Alert me if a correction is posted
Services
Email this article to a friend
Similar articles in this journal
Similar articles in ISI Web of Science
Similar articles in PubMed
Alert me to new issues of the journal
Add to My Personal Archive
Download to citation manager
Search for citing articles in:
ISI Web of Science (2)
Request Permissions
Google Scholar
Articles by Sarkola, T.
Articles by Helander, A.
PubMed
PubMed Citation
Articles by Sarkola, T.
Articles by Helander, A.