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.

Driving performance in adults with ADHD: results from a randomized, waiting list controlled trial with atomoxetine

PURPOSE

To investigate effects of a 12-week treatment with atomoxetine (ATX) on driving performance in real traffic, driving-related neuropsychological performance tests and self-evaluation of driving in adult patients with ADHD compared to an untreated control group with ADHD.

METHODS

Parallel group design with an ATX and a waiting list group. At baseline and endpoint patients were evaluated with a standardized on-road driving test (SDBO), a driving-related neuropsychological test battery (Act and React Test System [ART2020]), and subjective measures of driving performance (one-week driving diary, Driver Coping Questionnaire).

RESULTS

Forty-three of the 64 included patients completed the study (n=22 ATX, n=21 controls). Mean intervention period was 11.9±3.0 weeks, mean daily ATX dosage was 71.6±14.9mg. At endpoint, 60.1% of patients treated with ATX and 0% of waiting list group had reduced ADHD symptoms by greater or equal to 30%. In SDBO, ATX group reduced driving errors in three of four driving performance categories (attention, P<0.05; risk-related self-control, P<0.005; driver skills, P<0.001), number of driving errors remained stable in control group. At endpoint, 47.6% of control group and 18.2% of ATX group (P<0.05) did not fulfil the driving fitness criteria according to German Guidelines (percentile rank less or equal to 16 in one or more subtests in ART2020). Total number of self-reported critical traffic situations decreased from 12.0 to 6.8 per week in ATX group (P<0.05) and remained stable in controls by 9.3 and 9.9 at baseline and endpoint (ns). Coping strategies with stressful traffic situations did not change within both groups.

CONCLUSION

Our study provides first evidence that treatment with ATX improves driving performance in real traffic in adults with ADHD.

Selective detection of phosphatidylethanol homologues in blood as biomarkers for alcohol consumption by LC-ESI-MS/MS

A new validated method for the quantitation of the abnormal phospholipid phosphatidylethanol (PEth)--a biomarker for ethanol uptake--has been developed by LC-ESI-MS/MS following miniaturised organic solvent extraction and reversed phase chromatography with phosphatidylbutanol (PBut) as internal standard. PEth homologues with two fatty acid substituents-PEth 18:1/18:1, PEth 16:0/16:0-were determined in post-mortem blood collected from heavy drinkers at autopsy and also in whole blood samples from a volunteer after a single 60 g-dose of ethanol. Furthermore, PEth 18:1/16:0 or its isobaric isomer PEth-16:0/18:1 was detected. In comparison to previous high-performance liquid chromatography (HPLC) methods with evaporative light scattering detection (ELSD), the LC-MS/MS-method is more sensitive--with a limit of detection below 20 ng/ml--and more selective for single PEth homologues, while ELSD has been used for detection of the sum of PEth homologues with approximately 10 times less sensitivity. LC-MS/MS enables monitoring of PEth homologues as biomarkers for harmful and prolonged alcohol consumption as with HPLC/ELSD earlier, where PEth is measurable in blood only after more than 50 g ethanol daily intake for more than 2 weeks. Because of its higher sensitivity, there is a potential to detect single heavy drinking by LC-MS/MS, when PEth is formed in very low concentrations. This opens a new field of application of PEth to uncover single or multiple heavy drinking at a lower frequency and with a larger window of detection in blood than before by HPLC/ELSD or by use of other direct markers, e.g. ethyl glucuronide or ethyl sulfate.

Preanalytic aspects in postmortem toxicology

The preanalytic phase has been recognized to have a substantial role for the quality and reliability of analytical results, which very much depend on the type and quality of specimens provided. There are several unique challenges to select and collect specimens for postmortem toxicology investigation. Postmortem specimens may be numerous, and sample quality may be quite variable. An overview is given on specimens routinely collected as well as on alternative specimens that may provide additional information on the route of administration, a long term or a recent use/exposure to a drug or poison. Autolytic and putrefactive changes limit the selection and utility of specimens. Some data from case reports as well as experimental investigations on drug degradation and/or formation during putrefaction are discussed. Diffusion processes as well as postmortem degradation or formation may influence ethanol concentration in autopsy specimens. Formalin fixation of specimens or embalmment of the corpse may cause considerable changes of initial drug levels. These changes are due to alterations of the biological matrix as well as to dilution of a sample, release or degradation of the drug or poison. Most important seems a conversion of desmethyl metabolites to the parent drug. Some general requirements for postmortem sampling are given based on references about specimen collection issues, for a harmonized protocol for sampling in suspected poisonings or drug-related deaths does not exist. The advantages and disadvantages of specimen preservation are shortly discussed. Storage stability is another important issue to be considered. Instability can either derive from physical, chemical or metabolic processes. The knowledge on degradation mechanisms may enable the forensic toxicologist to target the right substance, which may be a major break down product in the investigation of highly labile compounds. Although it is impossible to eliminate all interfering factors or influences occurring during the preanalytic phase, their consideration should facilitate the assessment of sample quality and the analytical result obtained from that sample.

Absinthe: attention performance and mood under the influence of thujone

OBJECTIVE

The aim of this study was to determine whether the impacts of absinthe on attention performance and mood were different from those experienced with beverages that contain only alcohol. The ingredient causing absinthe's toxicity is believed to be thujone.

METHOD

A total of 25 healthy subjects participated in the study. An attention performance test and two questionnaires testing different mood dimensions were used. Three drinks with an identical amount of alcohol but with different amounts of thujone were offered.

RESULTS

The results of the present study showed that the simultaneous administration of alcohol containing a high concentration of thujone had a negative effect on attention performance. Under this condition, the subjects tended to direct their attention to signals in the central field of attention and to neglect peripheral signals; the number of correct reactions decreased significantly in the peripheral field of attention, and reaction time and the number of "false alarm" reactions increased significantly. The effects were most prominent at the time of the first measurement. When the subjects were under the influence of alcohol or were administered both alcohol and a low thujone concentration, these effects were not observed. The assessment of mood state dimensions showed that the anxiolytic effect of alcohol was temporarily counteracted by a high thujone concentration.

CONCLUSIONS

As they are apparently opposed to the effect of alcohol, the reactions observed here can be explained by the antagonistic effect of thujone on the gamma-aminobutyric acid receptor. Similar alterations were observed for the other mood state dimensions examined.

The role of active metabolites in dihydrocodeine effects

OBJECTIVE

The metabolism of dihydrocodeine to dihydromorphine, a high affinity mu-opioid receptor ligand in membrane homogenates, is catalyzed by CYP2D6. However, it is not clear whether an active CYP2D6 enzyme is required for opioid receptor-mediated effects in man after standard dihydrocodeine doses.

METHODS

Whole cell opioid-receptor affinity and effects on cAMP accumulation of dihydrocodeine and its metabolites were determined in differentiated SH-SY5Y neuroblastoma cells. In a double-blind, 2-period, placebo-controlled randomized crossover pilot study the pharmacokinetics of dihydrocodeine (60 mg single dose) and its metabolites were examined in 5 phenotyped extensive (EMs) and 4 poor metabolizers (PMs) for CYP2D6, and pharmacodynamics were evaluated using a pain threshold model and dynamic pupillometry.

RESULTS

Displacement binding and cAMP accumulation experiments showed clearly higher affinities (100- and 50-fold) and activities (180- and 250-fold) of dihydromorphine and dihydromorphine-6-glucuronide, respectively, whereas the other metabolites had similar or lower affinities and activities as compared to dihydrocodeine. The clinical study revealed no significant difference in plasma or urine pharmacokinetics between EMs and PMs for dihydrocodeine and its glucuronide. Dihydromorphine and its glucuronides were detectable in EMs only. A clear reduction of initial pupil diameters was observed up to 6 hours postdose in both PMs and EMs, with no obvious differences between CYP2D6 phenotypes. In the pain threshold model no effects were observed in either group.

CONCLUSION

CYP2D6 phenotype has no major impact on opioid receptor-mediated effects of a single 60 mg dihydrocodeine dose, despite the essential role of CYP2D6 in formation of highly active metabolites.

Preliminary approach to elucidate the role of pigment as a binding site for drugs and chemicals in anagen hair: differential uptake of 3H-haloperidol by pigment-producing compared to non-pigment-producing cell lines

A striking difference was observed for cellular-bound drug in HaCaT and Sk-Mel-1 cells for a fixed drug exposure time of 72 h and varying 3H-haloperidol concentrations in the culture media. Drug uptake was dependent on drug concentration and linearly correlated for both the non-pigment- and the pigment-producing cells which however was different in magnitude. In an additional investigation the time course of drug uptake during 3H-haloperidol exposure (400 pmol/ml; 28 days) revealed increasing drug concentrations in the Sk-Mel-1 population, whereas drug concentrations in the keratinocytes reached a plateau within a short time period. In contrast to the HaCaT cells no tendency to saturation was observed for the pigment-producing cell line. At the end of the experiments 3H-haloperidol concentrations in Sk-Mel-1 were found to be approximately tenfold higher than in HaCaT.

Preliminary approach to elucidate the role of pigment as a binding site for drugs and chemicals in anagen hairs: pigments as carriers for 3H-haloperidol in HaCaT/Sk-Mel-1 co-cultures

In view of the melanin-binding characteristics of haloperidol and its differential uptake by pigment- and non-pigment-producing cells, a co-culture of HaCaT with Sk-Mel-1 cell lines was performed to investigate whether melanosomes act as carriers for drug molecules associated with the pigments. Initially, HaCaT and Sk-Mel-1 cells were separately cultivated in the presence of 3H-haloperidol (400 pmol/ml medium ) for 28 days followed by subsequent co-cultivation in the absence of 3H-haloperidol for 5 days. The transfer of pigments into the keratinocytes during co-culture was confirmed by transmission electron microscopy. After the co-culture experiments a striking increase (> or = 50%) of 3H-haloperidol was observed in the pigmented HaCaT cells compared to the unpigmented keratinocytes. The present study proved the role of pigments as carriers for melanin-associated drug molecules. The results supported the hypothesis that hair pigment might be a factor affecting the outcome of hair assays for particular categories of commonly used licit and illicit substances. The chosen cell lines and the developed co-culture system may represent suitable in vitro models to study differential drug uptake into cell populations present in the skin or in the growing hair follicle as well as to elucidate drug uptake due to melanocyte-keratinocyte interactions.

[Serum beta-glucuronidase activity in polytrauma patients and in centrifuged autopsy blood samples]

The serum activity of beta-glucuronidase was investigated in 58 patients after severe trauma as well as in 43 autopsy cases. In 10 cases the enzyme activities in postmortem blood samples from the femoral vein were compared to those present in the correspondent heart blood samples. An elevated activity of beta-glucuronidase was observed in 14% of the patients within the first 36 h after severe trauma increasing to 62% in blood samples collected later on. The activity of beta-glucuronidase in the heart blood samples was always higher than in the corresponding sample from the femoral vein. In cases of prolonged post-mortem interval an elevated activity might have been due to bacterial contamination. In postmortal blood samples from the femoral vein an elevated enzyme activity was found in 70% of the study material. The results of the preliminary study on the activity of beta-glucuronidase in blood samples frequent in forensic routine work indicated that an elevated enzyme activity might be present for the following scenery: after severe trauma, in alcohol/drug abuse, presence of putridity/autolysis, presence of inflammatory processes, in diabetes as well as in carcinoma diseases. The significance of elevated beta-glucuronidase activity concerning alterations of unconjugated drug concentration due to in vitro cleavage of O-glucuronides should be investigated.

Analysis of cocaine, benzoylecgonine, ecogonine methyl ester, and ecgonine by high-pressure liquid chromatography-API mass spectrometry and application to a short-term degradation study of cocaine in plasma

A method for the determination of cocaine (COC), benzoylecgonine (BE), ecgonine methyl ester (EME), and ecgonine (ECG) in plasma by liquid chromatography-mass spectrometry (LC-MS-MS) was developed. The analytes were isolated from human plasma by subsequent solid-phase extraction and were separated on a Zorbax Eclipse XDB-C8 narrow-bore column using an ammonium acetate buffer/acetonitrile/methanol gradient. A Turbolonspray source was used for ionization. The analytes were characterized by their particular molecular ion and several fragments. Multiple reaction monitoring (MRM) was used for isolation and quantitation. The assay was rapid, highly sensitive, and reliable. The method was applied to monitor the in vitro degradation of cocaine in plasma. Fresh unpreserved and preserved (0.25% KF) plasma samples were spiked with 1,000 ng cocaine/mL. Aliquots of both series were stored at 4 degrees C and 20 degrees C and were analyzed at selected storage times of up to 15 days. In all samples, degradation of cocaine that was dependent on storage time and temperature and on sample preservation could be observed. The formation of BE did not occur to a significant extent (< 12%, referred to the initial concentration of COC), and its concentration was slightly higher in preserved compared with unpreserved plasma at both storage temperatures chosen. EME was formed in considerably higher amounts compared to BE. As already observed for COC, its formation and degradation were dependent on storage time, temperature, and preservation. EME is suggested to be the major source of ECG, which was detectable in all samples after 1-2 days of storage. Although the degradation of COC was shown to be highly dynamic in nature, the sum of all hydrolysis products of COC accounted for the initial COC concentration at any particular time of storage. Therefore, production of hitherto unknown degradation products of COC seems unlikely. Moreover, the common transformation product of BE and EME appeared to be stable, and ECG is suggested as a promising postcollection artifact.

Saliva testing after single and chronic administration of dihydrocodeine

In the present study, concentrations of dihydrocodeine and its metabolites in saliva and serum were compared after single low-dose and chronic high-dosage administration of the drug. In the first investigation, blood and saliva were collected periodically from six subjects after oral administration of 60 mg dihydrocodeine. In the second study, 20 subjects on oral dihydrocodeine maintenance provided single samples of blood and saliva simultaneously. Serum protein binding of salivary analytes and their recovery from the adsorbing material of the collection device as well as pH values of saliva samples were determined. The fluids were analyzed for dihydrocodeine and the major metabolites by high-performance liquid chromatography. In the single dose study dihydrocodeine was the only analyte found in saliva for up to 12-24 h post-dose. The half-life of dihydrocodeine in saliva was about twice that found in blood. The ratios of saliva/serum concentrations ranged from 1.2 to 17.0. After chronic high-dosage use, dihydrocodeine was the main salivary analyte and N-nordihydrocodeine was present in a few samples. Saliva/serum concentration ratios of dihydrocodeine were strongly dependent on the pH value of saliva and, to a lesser extent, on serum-protein binding. The saliva/serum ratios were more similar after chronic administration. The data suggest a passive diffusion process as the underlying mechanism for the transport of dihydrocodeine into saliva. After both single and chronic use, the presence of the drug in saliva can be used as evidence of recent substance administration.

[Passive exposure in detection of low blood and urine cannabinoid concentrations]

Whenever small amounts of drugs are present in blood or urine samples, especially of substances that are preferentially smoked such as cannabinoids, the discrimination between active and passive inhalation may cause severe problems. The statement of a passive exposure by marijuana smoke has been scrutinized reviewing the literature. The pharmacokinetics of smoked marijuana as well as experimental data on cannabinoid concentrations in plasma and urine samples following passive exposure are summarized. As a conclusion it seems urgent to enlarge the existing data base.

In vitro stability of cocaine in whole blood and plasma including ecgonine as a target analyte

The in vitro stability of cocaine (COC) was monitored in fresh whole blood and plasma stabilized with potassium fluoride (0.25%) for as long as 15 days. The samples were stored at 4 degreesC, 20 degreesC and 40 degreesC. Additionally, fresh plasma samples containing either benzoylecgonine (BZE), ecgonine methyl ester (EME) or ecgonine (ECG) were stored at 4 degreesC and 20 degreesC. Data were established using subsequent solid-phase extraction procedures and high-performance liquid chromatography coupled to atmospheric pressure ionization mass spectrometry for isolation and quantitation of COC, BZE, EME, and ECG. COC, BZE, and EME concentrations decreased with increasing storage temperature and time after an apparent first-order reaction kinetic. Only ECG appeared to be stable at storage temperatures as high as 20 degreesC for the entire observation period. At 40 degreesC, the amount of ECG produced from hydrolysis of COC still totalled 80% of the initial COC concentration. Hydrolysis of COC to EME occurred more rapidly in plasma than in blood. The dynamic degradation profiles obtained were dependent on the storage temperature. The conversion of COC to BZE, EME, and ECG appeared to be stoichiometric at all time intervals at storage temperatures of 4 degreesC and 20 degreesC. The presence of any hydrolysis product of COC in blood or plasma constitutes confirmatory evidence of COC incorporation, and determination of ECG seems most promising even in samples stored under unfavorable conditions.

[Detection of cocaine in blood stains]

Cocaine is rapidly degraded in blood samples, and its degradation was found to be highly dynamic in nature. The analysis of blood spots dried on filter paper may provide a method to minimize the break-down of cocaine and to largely preserve the analytical profile of the parent drug and its hydrolysis products at the time of sampling. The short term stability of cocaine in 100 microL blood spots prepared from unpreserved and preserved (sodium fluoride, 0.25%) blood samples was compared to the stability of the particular whole blood specimens stored in tubes at ambient temperature and at -20 degrees C. Due to dehydration, both the chemical and the enzymatic hydrolysis of cocaine and its products could be stopped in dried blood spots. More than 75% of the initial cocaine concentration could be detected in the blood spots, and the analytical profile was ensured for 17 days. Provided its practical suitability, the spot technology should offer a simple approach to detect actual impairment of motorists taken in police custody in the view of section 24a of the German traffic act as well as in cocaine associated criminal cases.

Stability of morphine, morphine-3-glucuronide, and morphine-6-glucuronide in fresh blood and plasma and postmortem blood samples

The present study was designed to determine the stability of morphine and its glucuronides in spiked fresh blood and plasma from live individuals as well as in four authentic postmortem blood specimens for a time interval of up to six months. The samples were stored in glass vials at -20 degrees C, 4 degrees C, and 20 degrees C. Additionally, spiked samples were exposed to light through window glass and subjected to a forced-degradation study at 40 degrees C. Data were established using solid-phase extraction and high-performance liquid chromatography coupled to atmospheric pressure ionization mass spectrometry for isolation and quantitation, providing a sensitive and specific detection method for the parent drug in the presence of its glucuronide metabolites. Morphine and its glucuronide metabolites were found to be stable in both blood and plasma at 4 degrees C for the whole observation period. In postmortem blood the analytes were stable only when stored at -20 degrees C. The thermal decomposition of morphine and morphine-6-glucuronide in spiked blood and plasma could be interpreted using pseudo first-order kinetics. Photodegradation of morphine-3-glucuronide in plasma was consistent with a second-order reaction. In postmortem samples the degradation pattern differed completely from that observed in fresh blood and plasma. The elevated morphine levels observed were primarily due to postmortem hydrolysis of morphine glucuronides.

[Distribution of morphine and morphine glucuronides in body tissue and fluids--postmortem findings in brief survival]

An intoxication following administration of morphine, tramadol and atracurium in a suicide case is reported. The route of administration and the amount of the particular drug were known from the investigation of the death scene and the findings of the postmortem examination. Tramadol was present in the gastric contents as well as in blood, liver, kidney and brain samples, whereas the drug could not be detected in muscle. All body fluids and tissues investigated contained morphine as well as its 3- and 6-glucuronides with the exception of muscle tissue. The concentrations of morphine and its glucuronide metabolites were determined by LC/MS following solid phase extraction. Interestingly, the concentration of M6G in brain, liver and kidney were close to the concentration of M3G in the particular tissue. This phenomenon might be explained by a preferential hydrolysis of M3G or by a preferential formation of M6G postmortem. Measurement of morphine and M6G in femoral blood and cerebrospinal fluid may be a useful indicator in rapid deaths.

Ethyl glucuronide in human hair

Ethyl glucuronide (EtG) is considered to be a promising candidate marker of alcohol consumption, but exhibits a short window of detection in blood or urine. Keratinized tissues are known to retain foreign substances and to provide a greater retrospective window of detection than body fluids. Therefore, post-mortem hair, skin swabs, and stratum corneum samples were collected from four subjects with a reported history of alcohol misuse and from seven subjects with a report of regular, socially accepted drinking behaviour, and were investigated for EtG. Additionally, certain specimens were collected from three children, who had not yet consumed any alcoholic beverages. EtG was detectable in most of the hair and stratum corneum samples as well as in perspiration stains from alcohol-consuming subjects. The results indicated that EtG might be formed locally in very small and highly variable amounts. The most important finding was that EtG cannot be expected to be generally detectable in keratinized tissues or perspiration stains from alcohol-drinking subjects, whereas a positive result is always associated with recent alcohol consumption.

[Serotonin, 5-hydroxyindolylacetic acid and cholesterol content in blood, cerebrospinal fluid and brain areas for differentiation of suicidal from non-suicidal cause of death]

In the present study serotonin and its metabolite 5-hydroxyindoleacetic acid was investigated in the cerebrospinal fluid and in discrete brain areas of the left and right hemisphere collected from 34 bodies. Sixteen subjects were suicide victims, and 18 were matched as controls. Matching was done for gender, age, sex and cause of death. In suicide victims the concentration of 5-hydroxyindoleacetic acid in cerebrospinal fluid (occipital) was significantly decreased whereas there was no difference comparing the particular results established from the various brain areas. Nevertheless, there was a non-significant trend towards a higher concentration of serotonin in the thalamic area and towards a lower level in samples collected from the mesencephalon in suicide brains. In suicide subjects, the level of 5-hydroxyindoleacetic acid was often found to be increased in the hippocampus and to be decreased in the thalamus. A differentiation between suicide and homicide seems promising only on condition that the distribution of serotonin and metabolite concentrations in various brain areas is considered. The amount of total cholesterol in blood is suggested to be of limited value.

Effect of the shampoo Ultra Clean on drug concentrations in human hair

The influence of the special shampoo Ultra Clean (Zydot Unlimited, Tulsa, Oklahoma) on the results of hair analyses was investigated. Hair samples from persons (n = 14) with a known history of drug abuse were collected at autopsy. The hair samples were divided into separate strands which were analyzed both after washing with Ultra Clean and without treatment. Hair analyses were performed by methanol extraction under sonication, purification by solid phase extraction and GC/MS in SIM mode according to routine procedures for tetrahydrocannabinol (THC), cocaine, amphetamine, methylenedioxyamphetamine (MDA), methylenedioxymethamphetamine (MDMA), methylenedioxyethylamphetamine (MDE), heroin, 6-monoacetylmorphine (6-MAM), morphine, codeine, dihydrocodeine and methadone. All drugs originally present in the hair fibers were still detected after a single application of Ultra Clean. However, a slight decrease in drug concentrations could mostly be observed e.g. cocaine (n = 10) -5%, 6-MAM (n = 12) -9%, morphine (n = 12) -26%, THC (n = 4) -36%. The findings clearly demonstrated that drug substances had not been sufficiently removed from human hair by a single Ultra Clean treatment to drop their concentrations below the limit of detection of the analytical method applied.

Report on intrauterine drug exposure during second trimester of pregnancy in a heroin-associated death

A 17-year-old girl was found dead in a public toilet with fresh needle puncture marks. She was 18-20 weeks pregnant with a male fetus. Drug screening of her blood and urine indicated recent heroin use. Chronic drug use was confirmed by hair analysis. Amniotic fluid as well as fetal and maternal tissues and body fluids were analyzed by GC/MS and HPLC. All the fetal specimens were investigated, and the following levels of drugs were found: 6-monoacetyl-morphine (blood: 152 ng/g; amniotic fluid: 128 ng/g; brain: 140 ng/g; lung: 110 ng/g; liver: 2 ng/g; kidney: 40 ng/g), morphine (blood: 1360 ng/g; amniotic fluid: 604 ng/g; brain: 710 ng/g; lung: 1030 ng/g; liver: 2060 ng/g; kidney: 1100 ng/g), codeine (blood: 70 ng/g; brain: 60 ng/g; lung: 60 ng/g; liver: 90 ng/g; kidney: 70 ng/g), and morphine-3-glucuronide (amniotic fluid: 209 ng/g; brain: 170 ng/g; lung: 325 ng/g; kidney: 231 ng/g). Morphine-6-glucuronide was present in the maternal circulation but could not be detected in the fetal circulation.

Perspiration versus saliva--basic aspects concerning their use in roadside drug testing

Various aspects concerning the practical application and forensic interpretation of data obtained by saliva drug testing and drug monitoring from the skin surface are discussed. Basic information on the composition of saliva and skin secretions and their particular transport mechanisms, as far as known, are given. For drugs of abuse secretion into saliva is suggested to be by passive diffusion and to depend on lipid solubility, pKa, plasma protein binding and on the pH of saliva. Drug molecules from blood are considered to reach the skin surface by various routes such as by sweat and sebum as well as by inter- and/or transcellular diffusion. The role of the stratum corneum as a temporary drug reservoir exceeding positive drug findings in urine is outlined. Current data on opioids, cocaine metabolites, cannabinoids and amphetamines detected in saliva and on the skin surface are reviewed. Aspects of collection, processing and analysis of the samples for implementation in roadside testing are addressed. The requirement of test sensitivity covering the broad concentration ranges and the importance of test specificity bearing in mind that the parent drug is the main analyte present in those specimens is stressed. Theoretical and practical findings on frequently abused drugs are discussed with regard to the possibilities and limitations of drug monitoring from saliva and perspiration to support a suspicion of actual or recent drug administration.

The detection of dihydrocodeine and its main metabolites in cases of fatal overdose

The levels of dihydrocodeine found in impaired individuals and in fatalities show a wide overlap in the ranges. Among other factors, the genetically controlled metabolism of dihydrocodeine should play an important role in dihydrocodeine toxicity. For the first time, the most important metabolites of dihydrocodeine were investigated in femoral blood from three fatal cases by simultaneous determination using HPLC and native fluorescence for detection. The amount of parent drug always exceeded dihydrocodeine-glucuronide formation and dihydromorphine concentrations ranged from 0.16-0.21 mg/L. The similar binding affinities of dihydromorphine and morphine to mu-opioid receptors suggest similar pharmacological effects and adverse reactions. The determination of the pharmacologically active metabolites should help to clarify the cause of death in fatal cases especially if a relatively low concentration of the parent drug is found.

The influence of the route of administration: a comparative study at steady state of oral sustained release morphine and morphine sulfate suppositories

Steady state pharmacokinetics of morphine (M), morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) were investigated in 6 patients with intractable cancer pain administered orally with MST (Mundipharma, Limburg, Germany) and, subsequently, rectally with MSR to make a judgment whether orally administered morphine can be replaced by rectally administered morphine. The parent drug and glucuronide metabolites were measured simultaneously using high-performance liquid chromatography (HPLC) and native fluorescence detection. The mean morphine area under the curve (AUC) value (0-8 h) was smaller (434.3 +/- 170.2 nmolL(-1)h) in the oral administration than in the rectal administration (574.8 +/- 285.0 nmolL(-1)h) (p < 0.05). The rectal administration resulted in less production of M3G and M6G. There were no significant differences in the mean steady state concentrations (C(ss)) of morphine, M3G, and M6G between the oral and rectal administrations (p > 0.05). The median AUC ratio--M3G/M and M6G/M, 12.58 and 1.85--following MSR rectal administration was smaller than following MST oral administration in 6 patients (19.97 and 2.59; p < 0.05), whereas the median AUC ratio M3G/M6G in the rectal dosing was 6.24 (range 5.2-7.6) was almost the same as the median ratio M3G/M6G in the oral dosing was 6.49 (range 5.8-8.5; p > 0.1). Four of the 6 patients had a greater Cmax of M3G and M6G after oral administration than after rectal administration. The same 4 had lower fluctuation rates for morphine, M3G (p < 0.05), and M6G (p < 0.05) after rectal administration. Therefore, during chronic morphine treatment, it still seems difficult to decide whether oral administration can be replaced by rectal administration.

Hemoglobin diffusion across a venous wall: an experimental study

The aim of this study was to investigate the permeation behavior of a large molecule through a venous wall; hemoglobin was chosen as a model substance. In vitro experiments were performed using a Chien-Valia diffusion chamber. Postmortem, hemolyzed, and fresh nonhemolyzed blood samples were investigated as permeants. Vein patches from vena cava inferior and vena jugularis interna were used as diffusion barriers. Applying this technique, extravasation of hemoglobin was detectable. The portion of hemoglobin molecules passing through the vascular wall depended on time, vein type, and graduation of hemolysis. The passage of hemoglobin across the wall of a large vein suggests intravascular changes in drug concentrations from postmortem blood samples not to be restricted on the unbound portion of the particular drug.

Formation and clearance of active and inactive metabolites of opiates in humans

The results of recent investigations of the analgesic and the nonanalgesic effects of opioid glucuronides are relevant to the research on drug abuse in forensic toxicology. As has been shown for heroin, knowledge of the state of distribution and elimination of active and inactive metabolites and glucuronides offers new possibilities in forensic interpretation of analytic results. Because of similar metabolic degradation, calculation of the time-dependent ratio of the concentration of morphine and its glucuronide metabolites in blood or serum allows a rough estimation of increased dosage and of time elapsed since the last application. Drug effects can be examined with respect to individual case histories, including overdose and survival time if the patient died. However, different methods of administration and the strong influence of different volumes or compartments of distribution of parent compounds and metabolites on concentrations in human body tissues require careful use of glucuronide concentration data. In Germany, dihydrocodeine (DHC) is prescribed as a heroin substitute, and relative overdoses are needed to be effective. DHC metabolism was studied in three patients who died from overdoses. All metabolites (dihydrocodeine-6-glucuronide [DHC6], nor-DHC [NDHC], dihydromorphine [DHM], nor-DHM [NDHM], and DHM-3- and 6-glucuronide [DHM3G, DHM6G]) were determined using HPLC and fluorescence detection. Concentrations of DHM (0.16 mg/L to 0.22 mg/L serum) were found. The DHM glucuronide ratios were similar to those of morphine. Receptor binding studies showed that the binding affinity of DHM to porcine mu-receptor was higher than that of morphine, and DHM6G's binding affinity was as high as that of morphine-6-glucuronide (M6G). Metabolites may play an important role in the effectiveness of DHC in substitution and toxicity. Because of enzyme polymorphism, the formation of DHC poses a risk for proper dosage in patients who are either poor or extensive metabolizers. The distribution of opioid glucuronides in cerebral spinal fluid in relation to transcellular transport in central nervous tissue is discussed with respect to the receptor binding of opiates and drug effect.

Postmortem distribution of dihydrocodeine and metabolites in a fatal case of dihydrocodeine intoxication

A report of a fatal dihydrocodeine ingestion under substitution therapy is given. Quantitation of dihydrocodeine, dihydromorphine, N-nordihydrocodeine, dihydrocodeine-6-, dihydromorphine-6- and dihydromorphine-3-glucuronide was performed simultaneously after solid-phase extraction prior to HPLC analysis, and the analytes were detected using their native fluorescence. Postmortem concentrations of blood samples from different sampling sites as well as from liver, kidney and cerebrum are reported. A hair sample was investigated to prove long-term use of the substitute drug. Site-to-site differences of the analytes from blood samples were very small. The partition behavior of the opioid glucuronides depended on the hematocrit value of the particular blood sample. Most important findings seemed that dihydromorphine and dihydromorphine-6-glucuronide concentrations decisively contributed to the toxicity of dihydrocodeine. This case report outlines that in dihydrocodeine related deaths the concentrations of the pharmacologically active metabolites should additionally be determined for reliable interpretation.

A preliminary study on the distribution of morphine and its glucuronides in the subcompartments of blood

The distribution of morphine, morphine-3-glucuronide (M3G), and morphine-6-glucuronide (M6G) in whole blood, plasma, and packed erythrocytes was studied. Parameters investigated were the hematocrit values (10, 42, 44, and 71%) and the water content of the samples. The blood-to-plasma ratio of morphine concentrations was unaffected by variations in hematocrit and water content, whereas the corresponding ratios for M3G and M6G were strongly influenced. Ratios were 0.53 to 0.65 and 0.52 to 0.62 in specimens with average hematocrit values (42 and 44%, respectively), and the ratios were 0.81 or 0.89 (hematocrit 10%) and 0.27 or 0.28 (hematocrit 71%) in blood samples with different hematocrit values. In contrast to the morphine conjugates, morphine was highly bound to or partitioned into red blood cells (beta e = 55.9). Although the present data are limited, they already demonstrate that conclusions drawn from pharmacokinetic studies and transferred to parent drug to metabolite ratios resulting from forensic blood samples may be biased by the particular biological matrix under investigation.

A preliminary study on the stability of benzodiazepines in blood and plasma stored at 4 degrees C

An approach to determine the stability of benzodiazepines and some of their metabolites (n = 13) by means of a routinely applied gas chromatographic method using electron capture detection was made in this preliminary study. Validation data of the method are given. Spiked blood and plasma samples were stored at 4 degrees C and analysed at selected times up to 240 days. The concentrations of all analytes had decreased to at least 60% of the original levels at the end of the observation period. A clear pattern of breakdown could not be established. The data obtained suggest that results from long-term stored samples should be interpreted cautiously. Further investigations concerning the stability of drugs in blood and plasma samples, additional methods of identification and determination as well as the establishment of optimal storage conditions seem necessary.

[Fatal poisoning with clozapine and perazine. A case report]

An intoxication following an apparent overdose of clozapine (Leponex) and perazine (Taxilan) is reported. There was a wide range of variation in postmortem blood and tissue concentrations of clozapine, desmethyclozapine and perazine. Clozapine/norclozapine blood and tissue ratios and perazine-pill-fragments in the gastric content could be used as a sign of suspected acute clozapine and perazine overdose.

Influence of pigmentation on the codeine content of hair fibers in guinea pigs

Tortoise shell guinea pigs (n = 7) were administered codeine (1 mg/mL codeine-base) in their drinking water for 3 weeks. Black, reddish-brown and white hair was collected separately from each animal before and after treatment. The hair samples were analyzed by GC/MS. The experiment showed positive results for all hair fibers with large individual variability of drug incorporation. Low drug intake resulted in small differences of the drug content in hair fibers different in color, whereas in cases of high drug intake a strong influence of hair pigmentation on the analytical results was observed. The highest drug content was always found in black hair samples, non-pigmented hair showed the lowest drug concentrations and the drug content in reddish-brown fibers was less than in black hair samples from the same animal. From the results it was concluded, that eumelanins rather than phenomelanins are the decisive factor for codeine-melanin binding in hair and the amount of drug intake was suggested to determine the relevance of hair pigmentation on the analytical results.

Ethyl glucuronide concentration in serum of human volunteers, teetotalers, and suspected drinking drivers

The kinetic profile of ethanol and ethyl glucuronide (EtG) in serum was investigated in three subject groups: 1) Healthy, moderately drinking volunteers (daily intake less than 30 g ethanol) who ingested a single dose of ethanol. In this group the maximum of serum ethyl glucuronide concentration (SEtGC) and of serum ethanol concentration (SEC) did not exceed 3.7 mg/L and 1.5 g/L respectively. EtG peaked 2 to 3.5 h later than ethanol. EtG was eliminated with a terminal half-life of 2 to 3 h. EtG decreased slower than ethanol--the metabolite could still be determined in serum up to 8 h after complete ethanol elimination. 2) In serum samples of teetotalers neither ethanol nor EtG could be found. 3) In 37 of 50 serum samples of drivers suspected of driving under the influence of ethanol, SEtGC was found between the limit of detection (0.1 mg/L) and 20 mg/L. If the SEC is less than 1 g/L and the SEtGC is significantly higher than 5 mg/L, we assume alcohol misuse.

A case report on drug screening of nail clippings to detect prenatal drug exposure

In a case of a sudden infant death syndrome-related death of a 3-month-old infant, nail clippings were positive for cocaine by gas chromatography-mass spectroscopy analysis that revealed a prenatal exposure to the drug substance. In utero exposure to drugs has been investigated using amniotic fluid, neonatal urine, meconium, and hair samples. Nail analysis offers some advantage over hair analysis because of its continuous growth and persistence after delivery. Nail material is easy to sample in suitable amounts. Currently, the cocaine finding cannot be related to the underlying cause of death. However, this observation indicates that nail analysis may be a new and valuable tool to screen newborns for intrauterine drug exposure. In addition, it can help collect information on the prevalence of possible embryotoxic effects and the link to postnatal manifestations of different dysfunctions in infants who are born by drug abusing mothers.

[Storage stability of flunitrazepam, flurazepam, diazepam and metabolites in blood and plasma]

The stability of flunitrazepam, flurazepam, diazepam and some of their metabolites in spiked blood and plasma samples was studied bei GC-ECD analysis at defined time intervals up to 240 days. Validation data of the method are given. The blood or plasma samples were stored either at 22 degrees C or at 4 degrees C, and were exposed to global natural light irradiation or protected from light. All substances considerably decreased during the time interval studied. Flunitrazepam soon disappeared completely at room temperature (22 degrees C), while diazepam and flurazepam proved to be more stable, but a clear pattern of breakdown could not be established. The data obtained suggest a result from a long-term stored sample to be cautiously interpreted. Further investigation concerning the stability of drugs and the establishment of optimal storage conditions seem necessary.

An in vitro experiment for postmortem vascular permeation. The passage of morphine and morphine glucuronides across a vascular wall

A venous blood sample taken at autopsy cannot be considered to represent the antemortem blood concentration of a particular substance. Autolytic processes cause disintegration and increasing permeability of the physiological and anatomical barriers such as vascular walls and lead to changes in substance concentrations. In the present study, the experimental design represents an in vitro postmortem simulation of a drug substance crossing a venous wall. The postmortem behavior of morphine, morphine-3- and morphine-6-glucuronide was investigated. A Chien-Valia-diffusion chamber with a patch of inferior vena cava as diffusion barrier was used. For optimal simulation of postmortem events, vein sampling was restricted to selected autopsy cases. Parameters for the analysis of diffusion across the vascular tissue were dependence on time, temperature, and initial substance concentrations. The penetration behavior simulating venous efflux and influx of the substances was studied by different orientation of the venous wall in the experiments. Rhodamine B was used as a model substance to visualize the binding to the tissue and the passage across the venous wall. The permeation of morphine, morphine-3- and morphine-6-glucuronide across a vein tissue was found to be mainly dependent on the disintegration of the vascular wall and on the postmortem time period as well as on concentration gradients. From the data of this preliminary in vitro study, it can be concluded that a lag time for transvascular diffusion exists postmortem. However, it could be demonstrated, that adsorption to and penetration into the vascular tissue may alter intraluminal blood concentrations even at an early stage of the postmortem time period.

Plasma concentrations of heroin and morphine-related metabolites after intranasal and intramuscular administration

The disposition of heroin and its metabolites was investigated in four healthy male volunteers following intranasal administration of 6 and 12 mg heroin hydrochloride. In addition, two doses of 6 mg heroin hydrochloride were injected intramuscularly for comparison of pharmacokinetic parameters. Serum samples were analyzed for heroin, 6-acetylmorphine, and morphine by solid-phase extraction-gas chromatography-mass spectrometry. The concentration of morphine glucuronides was determined by high-performance liquid chromatography based on the native fluorescence of the conjugates. Major findings were rapidly rising and declining terminal phases for heroin and 6-acetylmorphine and slowly declining phases of morphine and metabolites after both routes of administration. The area under the curve values of morphine-3-glucuronide depended on dose but not on route of administration. The apparent terminal half-lives of morphine-3-glucuronide ranged from 2.2 to 5.2 h for intranasally administered heroin and were 3.0 and 1.7 h for the intramuscularly applied drug. A mean morphine-3-glucuronide-heroin area-under-curve ratio of 93 for the intranasal route as compared with 38 for the intramuscular route demonstrated that circulating amounts of heroin were about half the size after intranasal administration of the same dose.