Discrimination between chewing of coca leaves or drinking of coca tea and smoking of "paco" (coca paste) by hair analysis. A preliminary study of possibilities and limitations.

BACKGROUND: Hair analysis is a suitable way to discriminate between coca chewers and consumers of manufactured cocaine using the coca alkaloids hygrine (HYG) and cuscohygrine (CUS) as markers. In the present preliminary study it was examined whether CUS and HYG can be detected in hair of occasional and moderate coca chewers or coca tea drinkers, whether CUS and HYG appear in hair of PACO consumers (smoking coca paste waste), and whether anhydroecgonine methyl ester (AEME) is a useful cocaine smoking marker in this context. METHOD: Three groups were included: 10 volunteers from Buenos Aires with occasional or moderate chewing of coca leaves or drinking coca tea, 20 Argentinean PACO smokers and 8 German cocaine users. The hair samples (1-4 segments) were analyzed by a validated LC-MS/MS method for cocaine (COC), norcocaine (NC), benzoylecgonine (BE), ecgonine methyl ester (EME), cocaethylene (CE), cinnamoylcocaine (CIN), tropacocaine (TRO), AEME, CUS and HYG. For comparison, eight samples of coca leaves or coca tea were analyzed. RESULTS: Only low concentrations of COC were found in hair of seven occasional users of coca leaves or coca tea (0.010-0.051 ng/mg). For three moderate chewers of coca leaves all compounds were detected including AEME but except TRO. The hair samples of PACO smokers contained much higher concentrations of COC (0.027-341 ng/mg, mean 37.4 ng/mg) and its metabolites. CUS was not found in these samples but traces of HYG were seen in 8 of 37 hair segments. AEME as a marker for coca smoking was detected in hair of 15 smokers. In comparison to COC, the concentrations of EME and CIN were higher for PACO smokers than for German cocaine consumers. AEME (56 ± 20 µg/g) was detected in all coca leave and coca tea samples which explains the detection of this substance in hair of coca chewers. Therefore, its use for differentiation between coca chewers and PACO smokers is limited. CONCLUSION: CUS remains to be the most suitable marker in hair for chewing coca leaves or drinking coca tea more frequently than two times per month since it does not appear in hair of Argentinean PACO smokers and German cocaine users. Contrary to a previous proposal, the ratios CIN/COC and EME/COC appeared not to be applicable as criteria for this purpose because of the higher concentration of these alkaloids in hair of PACO smokers. More research is needed to assess the value of AEME in hair of South American coca leave or cocaine users.

Oral fluid testing for illicit substance use in preanaesthetic care.

OBJECTIVE: Due to specific risks associated with illicit drug use, the preanaesthetic detection of illicit substances is essential. This prospective observational study evaluated oral fluid testing and self reporting of illicit drug use compared with confirmatory blood testing. METHODS: Consecutively enrolled preanaesthetic and emergency room patients (n=939) completed a paper-based lifestyle questionnaire. An oral fluid sample was obtained and analysed for illicit substance use by a point-of-care testing device (Dräger Drugtest® 5000). Patients who tested positive by self reporting or oral fluid testing underwent confirmatory blood testing (n=117). RESULTS: Self reporting revealed more overall illicit substance use and more users of cannabinoids, amphetamines, opioids, cocaine and benzodiazepines than oral fluid testing. Self reporting was more sensitive than blood testing for the detection of overall illicit substance use, and for use of cannabinoids and benzodiazepines. CONCLUSIONS: Self reporting revealed higher rates of illicit substance use than oral fluid testing in preanaesthetic patients, and may lead to more interventions and more appropriately tailored treatment and anaesthesia compared with oral fluid testing.

Practical experiences in application of hair fatty acid ethyl esters and ethyl glucuronide for detection of chronic alcohol abuse in forensic cases.

This article presents results from 1872 hair samples, which were analyzed for fatty acid ethyl esters (FAEEs) and ethyl glucuronide (EtG). The results were evaluated in the context of self-reported drinking behavior, the use of hair cosmetics, the gender of the sample donors and hair sample length. For comparison, CDT and GGT in serum were available in 477 and 454 cases, respectively. A number of alcohol abstainers or low moderate drinkers and excessive drinkers were selected for assessment of cut-offs for FAEEs in the proximal 6cm hair segments and for EtG in the proximal 3cm hair segments. Cut-off values were assessed by ROC analysis. It was found that the cut-offs of 1.0ng/mg FAEE and 30pg/mg EtG presently used for excessive drinking lead to a low portion of false positives (4% and 3% respectively) but to a higher portion of false negatives (23% and 25% respectively). Comparison of the mean and medium concentrations in samples without any reported hair cosmetics (N=1079) and in samples with reported use of hair spray (N=79) showed an increase by the factor of about two for FAEE but no significant difference for EtG. Mean values of EtG were decreased by 80% in bleached samples (N=164) and by 63% in dyed samples (N=96). There was no significant effect of bleaching and dyeing on FAEE. Hair gel and hair wax, oil or grease showed no significant effect on both FAEE and EtG. With respect to gender and investigated hair length ambiguous results were obtained because of major differences in the compared subpopulations of male with higher alcohol consumption and mainly shorter hair, and less drinking female with longer hair. For excessive drinkers FAEEs in the 0-6cm hair segment and EtG in the 0-3cm segment decreased with increasing time of reported abstinence before sample collection. These drinkers attain the level of teetotalers only after more than 10 months of abstinence. In comparison to scalp hair, FAEEs recovered from armpit hair and leg hair were lower and from chest hair were higher. EtG in armpit hair was lower and in leg hair higher than in scalp hair. It is concluded that the combined use of FAEE and EtG essentially increases the accuracy of interpretation since both markers complement each other by a different sensitivity to sources of error.

Workplace alcohol testing program by combined use of ethyl glucuronide and fatty acid ethyl esters in hair.

AIMS: The applicability of fatty acid ethyl esters (FAEEs) and ethyl glucuronide (EtG) in hair in a workplace alcohol testing program was investigated. METHODS: A total of 78 hair samples from employees in jobs with a high endangering potential were tested for EtG and FAEEs. In most cases excessive drinking was suspected. For 59 of these cases additional data of the traditional alcohol markers aspartate aminotransferase, alanine aminotransferase and gamma-glutamyltransferase and of the mean corpuscular volume of the erythrocytes (58 cases) were available. RESULTS: By application of the cut-offs of the Consensus of the Society of Hair Testing and of a gradual system for combined interpretation of FAEEs and EtG in hair no indications of alcohol abuse were obtained in 50 cases (64%), slight indications were seen in 13 cases (17%) and clear indications in 11 cases (14%). In four cases, the results were inconclusive with strongly conflicting results of both markers, the reason for which could not be cleared. The traditional markers confirmed the hair results only partly and displayed altogether a lower portion of positive results. CONCLUSION: EtG and FAEEs in hair, especially when interpreted in combination, are suitable for application in workplace alcohol testing programs. Nevertheless, the results obtained by hair analysis for alcohol markers can only be one part of a proper assessment aiming at the question whether an employee is addicted to alcohol or not.

Combined use of fatty acid ethyl esters and ethyl glucuronide in hair for diagnosis of alcohol abuse: interpretation and advantages.

In this study the combined use of fatty acid ethyl esters (FAEE) and ethyl glucuronide (EtG) for diagnoses of chronically excessive alcohol abuse is investigated at 174 hair samples from driving ability examination, workplace testing and child custody cases for family courts and evaluated with respect to the basics of interpretation. Using the cut-off values of 0.50 ng/mg for FAEE and 25 pg/mg for EtG, both markers were in agreement in 75% of the cases with 103 negative and 28 positive results and there were 30 cases with FAEE positive and EtG negative and 13 cases with FAEE negative and EtG positive. As the theoretical basis of interpretation, the pharmacokinetics of FAEE and EtG is reviewed for all steps between drinking of ethanol to incorporation in hair with particular attention to relationships between alcohol dose and concentrations in hair. It is shown that the concentrations of both markers are essentially determined by the area under the ethanol concentration in blood vs. time curve AUC(EtOH), despite large inter-individual variations. It is demonstrated by calculation of AUC(EtOH) on monthly basis for moderate, risky and heavy drinking that AUC(EtOH) increases very strongly in the range between 60 and 120 g ethanol per day. This specific feature which is caused by the zero-order elimination of ethanol is a favorable prerequisite for a high discrimination power of the hair testing for alcohol abuse. From the consideration of the different profiles of FAEE and EtG along the hair and in agreement with the literature survey, a standardized hair segment 0-3 cm is proposed with cut-off values of 0.5 ng/mg for FAEE and 30 pg/mg for EtG. This improves also the agreement between FAEE and EtG results in the cases of the present study. A scheme for combined interpretation of FAEE and EtG is proposed which uses the levels of abstinence and the double of the cut-off values as criteria in addition to the cut-off's. Considering the large variations in the relationship between ethanol dose and FAEE and EtG concentrations in hair, the combined use of both parameters strongly increases the accuracy of the diagnosis by mutual confirmation and identification of false positive or false negative results due to biological variations or analytical errors.

Detection and quantification of fatty acid ethyl esters in meconium by headspace-solid-phase microextraction and gas chromatography-mass spectrometry.

Meconium fatty acid ethyl esters (FAEEs) are currently used as biomarkers to detect heavy prenatal alcohol exposure. We introduce a novel technique to quantify FAEEs in meconium using headspace-solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS). This method improves on previous approaches by decreasing sample preparation time, eliminating the need for organic solvents, and reducing the required sample size. Using 50mg of meconium, the detection limits of FAEEs ranged from 0.05 to 0.16 nmol/g and had good reproducibility making it ideal for routine analysis of clinical samples.

Nervus medianus evoked potentials and bispectral index during repeated transitions from consciousness to unconsciousness.

BACKGROUND: We investigated the relationship between median nerve somatosensory evoked potentials (SSEPs) and the bispectral index (BIS) during alternating periods of consciousness and propofol-induced unconsciousness. METHODS: Loss of consciousness (LOC) was repetitively induced by bolus injections of propofol in 24 patients undergoing elective surgery in spinal anaesthesia. SSEP and the BIS were recorded during LOC and recovery of consciousness (ROC). The level of consciousness was clinically assessed by the observer's assessment of alertness/sedation scale. Propofol venous plasma concentrations were measured simultaneously. RESULTS: At LOC, all SSEPs latency components were prolonged (P<0.001), whereas amplitudes of the components > or = 45 ms were smaller (P=0.008) and the BIS values were lower (P<0.001). None of the EEG variables regained baseline levels during ROC. Regression analyses revealed that the SSEP components (five latencies and five amplitudes) explained 33% of the variance when predicting ROC; the BIS explained 12%. The combination of SSEP and BIS explained 37% of variance in this patient sample. Propofol venous plasma concentration was 1.2 (0.8) microg ml(-1) during LOC and 0.4 (0.5) microg ml(-1) during ROC. CONCLUSIONS: The present results indicate the usefulness of combining variables of the evoked and spontaneous EEG to measure different levels of consciousness, because the SSEP provide additional information beyond the BIS. Inter-individual variability of all the EEG variables limits their predictive potency of ROC after propofol infusion.

Narcotrend-assisted propofol/remifentanil anaesthesia vs clinical practice: does it make a difference?

BACKGROUND: The Narcotrend is a computer-based EEG monitor designed to measure the depth of anaesthesia. The aim of the present study is to test the hypothesis that the intraoperative level of anaesthetic depth differs if decision-making is guided by Narcotrend monitoring or not. METHODS: Forty-eight patients undergoing elective surgery were randomized to receive a Narcotrend-controlled propofol/remifentanil anaesthetic regimen or standard clinical practice. In the EEG group, anaesthesia was adjusted to achieve a Narcotrend level of D2-E0, which is recommended for moderate to deep anaesthetic depth for surgery. EEG values were recorded continuously every 20 s in both groups. Depending on data distribution, group comparisons of the EEG parameters, propofol plasma concentration, and recovery characteristics were performed by analysis of variance for repeated measurements or non-parametric statistics. RESULTS: About 62 (sd 29)% of the Narcotrend values were within the target level in the EEG group during maintenance of anaesthesia; this was true for 64 (26)% of the data in the non-EEG group. The variance of the Narcotrend data was significantly lower in the EEG group compared with the non-EEG group [median: 0.4 (range: 3.5) vs 0.6 (2.5); P = 0.048]. There was no difference in propofol or remifentanil dosage, propofol plasma concentrations, and time for extubation. Ten minutes after extubation, visual analogue scores for nausea indicated a lower incidence in the Narcotrend group [7 (15) vs 24 (34); P = 0.005]. CONCLUSIONS: Guidance of anaesthesia with the Narcotrend-monitor leads to fewer deviations from a defined target than clinical assessment of anaesthetic depth only. This results in lower scores of nausea in the immediate period after anaesthesia.

Psychomotor dysfunction after remifentanil/propofol anaesthesia.

BACKGROUND AND OBJECTIVES: Early recovery after anaesthesia is gaining importance in fast track management. The aim of this study was to quantify psychomotor recovery within the first 24 h after propofol/remifentanil anaesthesia using the Short Performance Test (Syndrom Kurztest (SKT)), consisting of nine subtests. The hypothesis was that psychomotor performance remains reduced 24 h after anaesthesia. METHODS: Thirty-seven patients scheduled for elective surgery took part in the study. The SKT was performed on the day before general anaesthesia (T0), 10, 30, 90 min and 24 h after extubation (T1). Parallel versions were used to minimize learning effects. Anaesthesia was introduced and maintained with remifentanil/propofol as a target controlled infusion. Propofol plasma concentration was measured 10 and 90 min after extubation. Perioperative pain management included novaminsulfon and piritramide. RESULTS: Up till 90 min after surgery and anaesthesia, psychomotor performances were significantly reduced as the lower test results in all SKT subtests indicated (P < or = 0.007 vs. baseline T0). In the three memory subtests (ST 2, ST 8 and ST 9), psychomotor performance was still reduced on the first postoperative day (P < or = 0.005; T1 vs. T0). There was no correlation between propofol plasma concentration and the psychometric test results. CONCLUSIONS: Propofol/remifentanil-based target controlled general anaesthesia for surgery is associated with a reduced psychomotor function up to the first postoperative day. Further studies are needed to confirm the usefulness of the SKT in the perioperative period and to clarify which components in the perioperative period are responsible for a lower performance in the SKT.

Squalene in hair--a natural reference substance for the improved interpretation of fatty acid ethyl ester concentrations with respect to alcohol misuse.

Fatty acid ethyl esters (FAEE) are incorporated into hair mainly from sebum. For this reason, the use of their concentration CFAEE as marker of excessive alcohol consumption is complicated by interindividual differences of the activity of the sebum glands and of elimination by hair care and hair cosmetics. Furthermore, an influence of the investigated hair length due to increasing accumulation from proximal to distal was found. Therefore, it was examined whether these sources of error can be avoided if in addition to CFAEE the relative FAEE concentrations CFAEE/CSQ related to squalene SQ as a natural reference compound were used for interpretation. Sebum contains about 10-20% SQ. A sensitive and reliable method for the determination of SQ in addition to FAEE from the same hair extracts by high performance liquid chromatography with photo diode array detector (HPLC-DAD) was developed. The concentrations of ethyl myristate, ethyl palmitate, ethyl oleate, ethyl stearate and squalene were determined and CFAEE/CSQ was calculated for 13 teetotallers, 16 social drinkers, 12 fatalities with excessive alcohol abuse at life time and 9 cases with unclear alcohol anamnesis. CSQ ranged from 0.02 to 1.97 microg/mg (mean 0.67 microg/mg). From the results follows that squalene enables a control of the lipid content of hair and a correction of CFAEE in cases with deviations from the usual lipid content in a similar way as creatinine in urine. Preliminary values of CFAEE/CSQ were suggested for the upper limit for teetotallers (< 0.6 ng/microg) and the lower limit for excessive alcohol abuse (> 1.5 ng/microg). However, the relative concentration CFAEE/CSQ cannot completely replace the absolute concentration CFAEE, and both should regularly be used for an improved interpretation with respect to alcohol abuse.

Comparison of ethyl glucuronide and fatty acid ethyl ester concentrations in hair of alcoholics, social drinkers and teetotallers.

In previous investigations hair analysis for ethyl glucuronide (EtG) and fatty acid ethyl esters (FAEE) proved to be suitable for the detection of excessive alcohol consumption. The aim of this study was to compare EtG and FAEE concentrations in hair of alcoholics, social drinkers and teetotallers. Hair samples from 10 alcoholics in withdrawal treatment, 11 fatalities with documented excessive alcohol consumption, four moderate social drinkers who consumed up to 20 g ethanol per day, and three strict teetotallers were analysed. After external degreasing with n-heptane, extraction with a dimethyl sulfoxide/n-heptane mixture and headspace solid-phase microextraction of the extracts, four fatty acid ethyl esters (FAEEs) (ethyl myristate, ethyl palmitate, ethyl oleate and ethyl stearate) were analysed by gas chromatography-mass spectrometry (GC-MS) with deuterated internal standards. EtG was determined by GC-MS/NCI after ultrasonication of the samples with H2O, cleanup by SPE with aminopropyl columns and PFP derivatisation. The following concentrations were measured for the four groups: teetotallers EtG < 0.002 ng/mg, FAEE 0.05-0.37 ng/mg, moderate social drinkers EtG < 0.002 ng/mg, FAEE 0.26-0.50 ng/mg, alcoholic patients EtG 0.030-0.415 ng/mg, FAEE 0.65-20.50 ng/mg and the fatalities with alcohol history EtG 0.072-3.380 ng/mg, FAEE 1.30-30.60 ng/mg. The results confirm that by using a cut-off value of the sum of FAEE > 1 ng/mg and/or a positive EtG result in hair, excessive alcohol consumption can be identified using hair analysis. However, no significant correlation between the EtG and FAEE concentrations in the positive cases could be shown. Segmental analysis of some of the specimens did not reveal the same distribution for EtG compared to FAEE in hair, and no chronological accordance compared to the self-reported alcohol consumption could be observed for both parameters. These different results of both methods are discussed in terms of differences between EtG and FAEE in mechanism of formation and incorporation into hair and elimination from hair.

Wipe-test and patch-test for alcohol misuse based on the concentration ratio of fatty acid ethyl esters and squalene CFAEE/CSQ in skin surface lipids.

Fatty acid ethyl esters (FAEE) are known to be formed in blood and almost all human tissues after alcohol consumption and to be incorporated from sebum into hair where they can be used as long-term markers for excessive alcohol consumption. In order to examine whether skin surface lipids which consist mainly of sebum are an equally useful matrix for measurement of FAEE as alcohol abuse markers, samples were collected by a wipe-test from the forehead of 13 teetotallers, 16 social drinkers, 10 death cases with known recent alcohol misuse and five death cases without indications of alcohol misuse. The samples were analysed by headspace solid-phase microextraction and gas chromatography-mass spectrometry for ethyl myristate, ethyl palmitate, ethyl oleate and ethyl stearate and by high performance liquid chromatography with photodiode array detector for squalene, (SQ), as a natural reference substance which the FAEE concentrations were related to. The ratio mFAEE/mSQ ranged between 0.16 and 1.12 ng/microg (mean 0.34 ng/microg) for the teetotallers and between 0.08 and 0.94 ng/microg (mean 0.37 ng/microg) for the social drinkers with no significant difference between both groups. For the alcoholics 2.4-24.2 ng/microg (mean 13.1 ng/microg) were found. For two volunteers the course of mFAEE/mSQ 2 weeks before and 3 weeks after a single high alcohol dose was pursued by daily wipe tests. A strong increase of mFAEE/mSQ occurred between 7 and 12 days after the drinking event. This delay can be explained by the transition time of about 8 days between sebum production and its appearance on the skin surface known from literature. For seven social drinkers skin surface lipid samples were also collected using drug of abuse patches of the firm PharmCheck. The ratios mFAEE/mSQ in these samples were in the same range as from the wipe-test. The comparison with the self-reported ethanol amounts consumed the week before and during the test gave no good correlation (R2 = 0.42). It can be concluded from the results that FAEE in skin surface lipids can be used for medium-term retrospective detection of heavy drinking.

Analytical investigations in a death case by suffocation in an argon atmosphere.

A 31-year-old engineer was found dead in a reaction vessel (diameter 0.8 m, height 1.8 m) of a bulb factory some minutes after he had entered it for repair work. Resuscitation attempts with artificial respiration were unsuccessful. Despite autopsy and usual toxicological analyses, no cause of death could be found. Since in the normal production process, argon was used as a protecting gas, the possibility of suffocation in an argon atmosphere was investigated. This was rendered more difficult because of the natural content of 0.93 vol.% argon in air and since the excessive argon could have been removed by the resuscitation attempts. Gas samples from larynx, esophagus, bronchi, and stomach, separated blood samples from both ventricles of the heart and from the vena iliaca externa as well as tissue samples from lung and liver were collected during autopsy into headspace vials in such a way that the loss of gas and a dilution by surrounding air was avoided as far as possible. The samples were analyzed by headspace GC-MS. The abundance of Ar+ (m/z = 40) was used for quantification with N2(2+) (m/z = 14) as internal standard. The following argon concentrations were measured (mean values, case under investigation/comparison cases): gas from larynx 1.79/0.96 vol.%, stomach gas 1.58/0.89 vol.%, heart blood (left ventricle) 7.2/2.7 microg/mL, heart blood (right ventricle) 5.8/2.7 microg/mL, blood from vena iliaca externa 3.6/2.7 microg/mL. A clearly increased concentration was also found in lung tissue, whereas in liver tissue no significant difference in comparison to other cases was measured. From the results, it follows that the deceased inhaled an increased amount of argon a short time before death. The concentrations are consistent with asphyxia and subsequent resuscitation attempts. They cannot be explained by a long-term inhalation of an atmosphere enriched with argon before the incident as it is likely to have occurred in this factory hall.

Fatty acid ethyl esters in hair as markers of alcohol consumption. Segmental hair analysis of alcoholics, social drinkers, and teetotalers.

BACKGROUND: Fatty acid ethyl esters (FAEEs) are products of nonoxidative ethanol metabolism. After incorporation in hair, they should be suitable long-term markers of alcohol abuse. METHODS: Hair samples from 19 alcoholics in a treatment program, 10 fatalities with verified excessive alcohol consumption, 13 moderate social drinkers who consumed up to 20 g ethanol/day, and 5 strict teetotalers were analyzed in 1-12 segments for four FAEEs (ethyl myristate, ethyl palmitate, ethyl oleate, and ethyl stearate) by external degreasing with n-heptane, extraction with a dimethyl sulfoxide-n-heptane mixture, headspace solid-phase microextraction of the extracts, and gas chromatography-mass spectrometry with deuterated internal standards. The n-heptane washings were analyzed in the same way for FAEEs from the hair surface. RESULTS: The sum of the four ester concentrations in hair calculated for the proximal 0-6 cm segment was 2.5-13.5 ng/mg (mean, 6.8 ng/mg) for the fatalities, 0.92-11.6 ng/mg (mean, 4.0 ng/mg) for 17 of the alcoholics in treatment, 0.20-0.85 ng/mg (mean, 0.41 ng/mg) for the moderate social drinkers, and 0.06-0.37 ng/mg (mean, 0.16 ng/mg) for the teetotalers. In almost all cases the segmental concentrations increased from proximal to distal. There was no agreement between the self-reported drinking histories of the participants and the FAEE concentrations along the hair length. Ethyl oleate was the dominant ester in all samples. CONCLUSIONS: FAEEs are deposited in hair mainly from sebum. Despite large individual differences, FAEE hair concentrations can be used as markers for excessive alcohol consumption with relatively high accuracy.

Analysis of fatty acid ethyl esters in hair as possible markers of chronically elevated alcohol consumption by headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS).

Fatty acid ethyl esters (FAEE) are products of the nonoxidative ethanol metabolism, which are known to be detectable in blood only about 24h after the last alcohol intake. After deposition in hair they should be suitable long-term markers of chronically elevated alcohol consumption. Therefore, a method for the analysis of ethyl myristate, ethyl palmitate, ethyl oleate and ethyl stearate from hair was developed based on the extraction of the hair sample by a dimethylsulphoxide (DMSO)/n-hexane mixture, separation and evaporation of the n-hexane phase and application of headspace solid-phase microextraction (HS-SPME) in combination with gas chromatography-mass spectrometry (GC-MS) to the extract. For use as internal standards, the corresponding D(5)-ethyl esters were prepared. The HS-SPME/GC-MS measurements were automatically performed using a multi-purpose sampler. The detection limits of the FAEE were between 0.01 and 0.04ng/mg and the reproducibility was between 3.5 and 16%. By application of the method to hair samples of 21 fatalities with known heavy alcohol abuse 0.045-2.4ng/mg ethyl myristate, 0.35-13.5ng/mg ethyl palmitate, 0.25-7.7ng/mg ethyl oleate and 0.05-3.85ng/mg ethyl stearate were measured. For social drinkers (30-60g ethanol per week), the concentrations were about one order of magnitude smaller. For 10 teetotalers negative results or traces of ethyl palmitate were found. It was shown by supplementary investigations in single cases that FAEE are also present in sebum, that there is no strong difference in their concentrations between pubic, chest and scalp hair, and that they are detectable in hair segments after a 2 months period of abstinence. From the results follows that the measurement of FAEE concentrations in hair is a useful way for a retrospective detection of alcohol abuse.

Screening method for seventy psychoactive drugs or drug metabolites in serum based on high-performance liquid chromatography--electrospray ionization mass spectrometry.

A screening method for 70 psychoactive drugs or drug metabolites in human serum by solid-phase extraction with subsequent high-performance liquid chromatography and electrospray ionization mass spectrometry was developed. Enhanced selectivity of detection was obtained by collision-induced dissociation using two different skimmer voltages for the individual scan. The mass spectra and the retention times of the compounds were incorporated into a self-generated spectra library for identification in screening experiments. The detection limits were found to be between 0.1 and 5 ng/mL serum for the majority of the compounds when measured in the selected ion mode. Because of the very small serum concentrations and the rather low extraction yield, lysergide could not be detected in this way. It was demonstrated with 140 serum samples from alcohol-related traffic cases that this method is suitable for a routine screening in a forensic laboratory.

Determination of methadone and its metabolites EDDP and EMDP in human hair by headspace solid-phase microextraction and gas chromatography-mass spectrometry.

A simple method for analysis of methadone and its two main metabolites EDDP and EMDP in hair was developed using automatic headspace solid-phase microextraction (HS-SPME) at a multipurpose sampler and gas chromatography-mass spectrometry with electron impact ionization and selected ion monitoring (GC-MS-SIM). The washed hair pieces were digested in the closed headspace vial in 1 ml 1 M NaOH containing 0.5 g NaCl and each 10 ng of the internal standards D9-methadone and D3-EDDP at 110 degrees C for 20 min. Then the HS-SPME was performed with a 65 microm polydimethylsiloxan/ divinylbenzene fiber at the same temperature in the same vial for another 20 min followed by the desorption in the GC injection port. The calibration curves were linear between 0.1 and 3 ng/mg (methadone and EMDP) and 10 ng/mg (EDDP) respectively, at higher concentrations a negative deviation from linearity was found. The detection limits were 0.03 ng/mg (methadone) and 0.05 ng/mg (EDDP and EMDP), and the reproducibility was 9.2% for methadone and 11.2% for EDDP (n= 12). The method was applied to hair samples of 26 drug fatalities. 19 cases were positive with 0.36-11.8 ng/mg methadone and 0.19 -10.8 ng/mg EDDP. EMDP was found only in two cases with 0.18 and 0.84 ng/mg. The methadone concentration range was in agreement with previous data, but the EDDP/methadone concentration ratios (0.19-0.67) were definitely higher than those determined by other methods.

Determination of lidocaine in hair of drug fatalities by headspace solid-phase microextraction.

The local anesthetic lidocaine was determined in hair by hydrolysis of the samples with 4% NaOH in the presence of excessive Na2SO4 and subsequent headspace solid-phase microextraction with a 65-microm Carbowax/divinylbenzene fiber, and gas chromatography-mass spectrometry measurement with etidocaine as the internal standard. The calibration curve was linear between 0.1 and 1000 ng/mg. The detection and quantitation limits were 0.1 and 0.4 ng/mg, respectively. The method was applied to hair samples of 49 drug fatalities, and positive results were obtained in 32 cases with lidocaine concentrations between 0.4 and 400 ng/mg and 675 ng/mg in one extreme case. For comparison, morphine, 6-acetylmorphine, codeine, dihydrocodeine, methadone, cocaine, and benzoylecgonine were also determined by usual methods. From segmental investigations in four of the cases and from comparison with the hair concentrations of the other drugs, it follows that lidocaine was consumed for a longer period of time as an adulterant of cocaine and heroin preparations.

Use of headspace solid-phase microextraction (HS-SPME) in hair analysis for organic compounds.

Headspace solid phase microextraction (HS-SPME) has advantages of high purity of the extract, avoidance of organic solvents and simple technical manipulation and can be used in combination with gas chromatography-mass spectrometry (GC-MS) in the hair analysis of a number of drugs. HS-SPME coupled with the hydrolysis of the hair matrix by 4% sodium hydroxide in the presence of excess sodium sulphate and of a suitable internal standard proved to be a convenient one-step method for the measurement of many lipophilic basic drugs such as nicotine, amphetamine derivatives, local anaesthetics, phencyclidine, ketamine, methadone, diphenhydramine, tramadol, tricyclic antidepressants and phenothiazines. Detection limits were between 0.05 and 1.0 ng/mg. From spiked 10-mg hair samples absolute recoveries between 0.04 and 5.7% were found. These recoveries decreased considerably if larger sample amounts were used, perhaps due to increased drug solubility in the aqueous phase or to elevated viscosity in the presence of dissolved hair proteins. Because of the phenolic hydroxyl group a change of pH after alkaline hair digestion (by adding excess orthophosphoric acid) was necessary for the detection of delta 9-tetrahydrocannabinol (delta 9-THC), cannabinol (CBN) and cannabidiol (CBD) by HS-SPME. Nevertheless, the detection limits were such that only CBN could be detected in hair of a consumer. Clomethiazole, a compound hydrolysed in alkali, was measured by HS-SPME after extraction with aqueous buffer. The detection limit was 0.5 ng/mg. Cocaine could not be detected by HS-SPME. The application of HS-SPME to hair samples from several forensic and clinical cases is described.

Are there possibilities for the detection of chronically elevated alcohol consumption by hair analysis? A report about the state of investigation.

The analysis of suitable ethanol markers in hair would be an advantageous tool for chronic alcohol abuse control because of the wide diagnostic window allowed by this specimen and the possibility of segmental investigation. Between the markers practically used or thoroughly investigated in blood or urine, ethylglucuronide, fatty acid ethylesters, phosphatidylethanol, acetaldehyde adducts to protein and 5-hydroxytryptophol can be regarded as possible candidates also in hair, but preliminary data were found in the literature only for ethylglucuronide and acetaldehyde modified proteins. By using headspace gas chromatography and headspace solid phase microextraction in combination with gas chromatography-mass spectrometry (SPME-GC/MS), in alkaline hydrolysates of hair it was possible to determine between 17 and 135 ng/mg of ethanol beside acetone and several other volatile compounds with slightly higher ethanol values for alcoholics than for social drinkers and teetotalers. A part of this is ethanol only absorbed in the hair matrix from the surrounding environment and consequently is not applicable as a diagnostic criterion. By extraction with aqueous buffer, methanol or a methanol/chloroform mixture and subsequent alkaline hydrolysis it was found that another part is generated from ethylesters, which are preferentially deposited in the lipid fraction of hair. In a specific search for ethylesters of 17 carboxylic acids by GC/MS-SIM in most cases ethyl 4-hydroxybenzoate (0.1 to 5.9 ng/mg, a preservative in hair cosmetics) and in four cases traces of indolylacetic acid ethylester were found. Furthermore, diethyl phthalate (a softening agent, present also in many cosmetic products) was identified in the hair of alcoholics as well as of children. As potential markers of alcohol intake, ethyl palmitate, ethyl stearate and ethyl oleate were detected in hair samples of alcoholics by headspace SPME-GC/MS of the chloroform/methanol extracts.